Merge pull request #803 from Nezreka/dev

2.6.7

.github/workflows/docker-publish.yml

@@ -9,9 +9,9 @@ on:
   workflow_dispatch:
     inputs:
       version_tag:
-        description: 'Version tag (e.g. 2.6.4)'
+        description: 'Version tag (e.g. 2.6.7)'
         required: true
-        default: '2.6.4'
+        default: '2.6.7'
 
 jobs:
   build-and-push:

config/settings.py

@@ -620,7 +620,13 @@ class ConfigManager:
                 "embed_tags": True
             },
             "playlist_sync": {
-                "create_backup": True
+                "create_backup": True,
+                # How a re-sync writes to the server playlist:
+                #   replace   — delete + recreate (default; today's behavior)
+                #   reconcile — edit in place (add/remove delta), preserving the
+                #               playlist's custom image, description, and identity (#792)
+                #   append    — only add new tracks, never remove
+                "mode": "replace"
             },
             "settings": {
                 "audio_quality": "flac"

core/acoustid_verification.py

@@ -17,6 +17,7 @@ from utils.logging_config import get_logger
 from core.acoustid_client import AcoustIDClient
 from core.matching_engine import MusicMatchingEngine
 from core.matching.version_mismatch import is_acceptable_version_mismatch
+from core.matching.script_compat import is_cross_script_mismatch
 from core.musicbrainz_client import MusicBrainzClient
 
 logger = get_logger("acoustid.verification")
@@ -655,10 +656,32 @@ class AcoustIDVerification:
                 and title_sim >= 0.80
                 and artist_sim >= ARTIST_MATCH_THRESHOLD
             )
-            if language_script_skip or high_confidence_strong_match_skip:
+            # Issue #797 — the EXPECTED artist and the AcoustID-matched
+            # artist are written in different scripts (e.g. "Joe Hisaishi"
+            # vs "久石譲") yet the alias-aware comparison still confirmed
+            # them as the same artist (artist_sim >= threshold, bridged via
+            # MusicBrainz aliases). When the artist itself spans scripts the
+            # title almost always does too — and a romanized-vs-native title
+            # comparison is meaningless, so it can't be evidence the file is
+            # wrong. Trust the confirmed artist + the fingerprint (already
+            # >= MIN_ACOUSTID_SCORE to reach here) and SKIP rather than
+            # quarantine a correct download of a non-English artist.
+            #
+            # Deliberately narrow (the "tight" scope): keyed on the ARTIST
+            # spanning scripts AND being confirmed. A same-script artist
+            # with only a cross-script TITLE (romaji artist + kanji title)
+            # is NOT covered — that case keeps the stricter 0.95 floor
+            # above, preserving the #607 wrong-file protection.
+            cross_script_artist_skip = (
+                best_score >= MIN_ACOUSTID_SCORE
+                and artist_sim >= ARTIST_MATCH_THRESHOLD
+                and is_cross_script_mismatch(expected_artist_name, display_artist)
+            )
+            if (language_script_skip or high_confidence_strong_match_skip
+                    or cross_script_artist_skip):
                 reason = (
                     "likely same song in different language/script"
-                    if language_script_skip
+                    if (language_script_skip or cross_script_artist_skip)
                     else "title/artist match within tolerance"
                 )
                 msg = (

core/artist_source_lookup.py

@@ -53,7 +53,11 @@ def find_library_artist_for_source(
 
     Lookup order:
       1. Direct match on the source-specific ID column (server-agnostic — any
-         library record with the right external ID is a hit).
+         library record with the right external ID is a hit). If that id is
+         stamped on MORE than one library artist, the mapping is corrupt /
+         ambiguous (e.g. an enrichment bug wrote one Deezer id onto several
+         artists) — we refuse to guess and fall through, so the caller can
+         show the source artist directly instead of an arbitrary wrong one.
       2. Case-insensitive name match within ``active_server`` (defaults to the
          active media server when not provided), so we don't jump the user
          across server contexts on a name collision.
@@ -67,13 +71,23 @@ def find_library_artist_for_source(
     try:
         with database._get_connection() as conn:
             cursor = conn.cursor()
+            # LIMIT 2 so we can tell a unique match from an ambiguous one.
             cursor.execute(
-                f"SELECT id, name FROM artists WHERE {column} = ? LIMIT 1",
+                f"SELECT id FROM artists WHERE {column} = ? LIMIT 2",
                 (str(source_artist_id),),
             )
-            row = cursor.fetchone()
-            if row:
-                return row[0]
+            rows = cursor.fetchall()
+            if len(rows) == 1:
+                return rows[0][0]
+            if len(rows) > 1:
+                # Same source id on multiple artists — corrupt mapping. Don't
+                # upgrade on the id; fall through to the name match (and, if
+                # that misses, let the caller render the source artist).
+                logger.warning(
+                    f"Source id {source}:{source_artist_id} maps to "
+                    f"{len(rows)}+ library artists — ambiguous, skipping "
+                    f"id-based library upgrade"
+                )
 
             if artist_name and active_server:
                 cursor.execute(

core/audiodb_worker.py

@@ -8,7 +8,7 @@ from datetime import datetime, timedelta
 from utils.logging_config import get_logger
 from database.music_database import MusicDatabase
 from core.audiodb_client import AudioDBClient
-from core.worker_utils import interruptible_sleep
+from core.worker_utils import accept_artist_match, interruptible_sleep
 
 logger = get_logger("audiodb_worker")
 
@@ -273,8 +273,13 @@ class AudioDBWorker:
 
     def _verify_artist_id(self, item: Dict[str, Any], result: Dict[str, Any]) -> bool:
         """Verify that the result's artist ID matches the parent artist's stored AudioDB ID.
+
         If mismatched, the album/track search is more specific (uses artist+title),
-        so we trust it and correct the parent artist's audiodb_id."""
+        so we trust it and correct the parent artist's audiodb_id — BUT only when
+        the result's artist *name* matches our parent artist. Without that guard,
+        a collaboration/compilation (a track our library credits to one artist
+        that lives on another artist's album) would stamp the wrong AudioDB id
+        onto our artist. See the Deezer fix for the full write-up."""
         parent_audiodb_id = item.get('artist_audiodb_id')
         if not parent_audiodb_id:
             return True
@@ -284,6 +289,18 @@ class AudioDBWorker:
             return True
 
         if str(result_artist_id) != str(parent_audiodb_id):
+            parent_name = item.get('artist') or ''
+            result_artist_name = result.get('strArtist') or ''
+            if (result_artist_name and parent_name
+                    and not self._name_matches(parent_name, result_artist_name)):
+                logger.info(
+                    f"Skipping artist-ID correction from {item['type']} "
+                    f"'{item['name']}': result artist '{result_artist_name}' "
+                    f"≠ parent '{parent_name}' (collab/compilation, not a "
+                    f"correction)"
+                )
+                return True
+
             logger.info(
                 f"Artist ID correction from {item['type']} '{item['name']}': "
                 f"updating parent artist AudioDB ID from {parent_audiodb_id} to {result_artist_id}"
@@ -409,14 +426,18 @@ class AudioDBWorker:
                 result = self.client.search_artist(item_name)
                 if result:
                     result_name = result.get('strArtist', '')
-                    if self._name_matches(item_name, result_name):
+                    ok, reason = accept_artist_match(
+                        self.db, 'audiodb_id', result.get('idArtist'), item_id,
+                        item_name, result_name,
+                    )
+                    if ok:
                         self._update_artist(item_id, result)
                         self.stats['matched'] += 1
                         logger.info(f"Matched artist '{item_name}' -> AudioDB ID: {result.get('idArtist')}")
                     else:
                         self._mark_status('artist', item_id, 'not_found')
                         self.stats['not_found'] += 1
-                        logger.debug(f"Name mismatch for artist '{item_name}' (got '{result_name}')")
+                        logger.debug(f"Artist '{item_name}' not matched: {reason}")
                 else:
                     self._mark_status('artist', item_id, 'not_found')
                     self.stats['not_found'] += 1

core/database_update_worker.py

@@ -41,7 +41,19 @@ class DatabaseUpdateWorker:
         self.database_path = database_path
         self.full_refresh = full_refresh
         self.should_stop = False
-        
+
+        # Track ids of rows newly INSERTED this run (not updates). The web
+        # layer reads this to gap-fill embedded provider IDs for the new files
+        # (auto-reconcile), so newly-added music contributes its
+        # Spotify/MusicBrainz/etc. ids without a manual backfill.
+        self._new_track_ids = set()
+
+        # Optional callback(worker) run as the FINAL scan phase, immediately
+        # before the 'finished' signal — so the auto-reconcile is inside the
+        # scan's running window (automations/UI treat it as a normal phase and
+        # wait for it). Injected by the web layer (which owns path resolution).
+        self.post_scan_hook = None
+
         # Statistics tracking
         self.processed_artists = 0
         self.processed_albums = 0
@@ -79,7 +91,26 @@ class DatabaseUpdateWorker:
                 callback(*args)
             except Exception as e:
                 logger.error(f"Error in callback for {signal_name}: {e}")
-    
+
+    def _emit_finished(self, *args):
+        """Run the post-scan hook (auto-reconcile) as the final phase, THEN
+        emit 'finished'.
+
+        Running the hook before 'finished' keeps the scan's status at
+        'running' through the reconcile, so every caller (automations that
+        poll for completion, the dashboard card, the Tools page) treats it as
+        a normal scan phase and waits for it — rather than seeing 'finished'
+        and missing the tail. Best-effort: a hook failure never blocks the
+        completion signal.
+        """
+        if self.post_scan_hook:
+            try:
+                self.post_scan_hook(self)
+            except Exception as e:
+                logger.warning(f"post-scan hook failed (non-fatal): {e}")
+        self._emit_signal('finished', *args)
+
+
     def connect_callback(self, signal_name: str, callback: Callable):
         """Connect a callback for progress notifications."""
         self.callbacks.setdefault(signal_name, []).append(callback)
@@ -146,7 +177,7 @@ class DatabaseUpdateWorker:
                                 logger.info(f"Merged {merged} duplicate artists")
                         except Exception as e:
                             logger.warning(f"Could not merge duplicate artists: {e}")
-                    self._emit_signal('finished', 0, 0, 0, 0, 0)
+                    self._emit_finished(0, 0, 0, 0, 0)
                     return
                 logger.info(f"Incremental update: Found {len(artists_to_process)} artists to process")
             
@@ -230,7 +261,7 @@ class DatabaseUpdateWorker:
             self.removed_tracks = removal.get('tracks_removed', 0) if removal else 0
 
             # Emit final results
-            self._emit_signal('finished',
+            self._emit_finished(
                 self.processed_artists,
                 self.processed_albums,
                 self.processed_tracks,
@@ -331,7 +362,7 @@ class DatabaseUpdateWorker:
                         f"{self.processed_albums} albums, {self.processed_tracks} new tracks, "
                         f"{stale_removed} stale tracks removed")
 
-            self._emit_signal('finished',
+            self._emit_finished(
                 self.processed_artists,
                 self.processed_albums,
                 self.processed_tracks,
@@ -880,6 +911,8 @@ class DatabaseUpdateWorker:
                                             track_success = self.database.insert_or_update_media_track(track, album_id, artist_id, server_source=self.server_type)
                                             if track_success:
                                                 total_processed_tracks += 1
+                                                if track_success == 'inserted':
+                                                    self._new_track_ids.add(str(track.ratingKey))
                                                 logger.debug(f"Processed new track: {track.title}")
                                         except Exception as e:
                                             logger.warning(f"Failed to process track '{getattr(track, 'title', 'Unknown')}': {e}")
@@ -1344,6 +1377,8 @@ class DatabaseUpdateWorker:
                                             skipped_count += 1
                                         elif track_success:
                                             track_count += 1
+                                            if track_success == 'inserted':
+                                                self._new_track_ids.add(track_id_str)
                                     except Exception as e:
                                         logger.warning(f"Failed to process track '{getattr(track, 'title', 'Unknown')}': {e}")
 

core/deezer_worker.py

@@ -8,7 +8,7 @@ from datetime import datetime, timedelta
 from utils.logging_config import get_logger
 from database.music_database import MusicDatabase
 from core.deezer_client import DeezerClient
-from core.worker_utils import interruptible_sleep, set_album_api_track_count
+from core.worker_utils import accept_artist_match, interruptible_sleep, set_album_api_track_count
 from core.enrichment.manual_match_honoring import honor_stored_match
 
 logger = get_logger("deezer_worker")
@@ -278,10 +278,19 @@ class DeezerWorker:
         logger.debug(f"Name similarity: '{query_name}' vs '{result_name}' = {similarity:.2f}")
         return similarity >= self.name_similarity_threshold
 
-    def _verify_artist_id(self, item: Dict[str, Any], result_artist_id) -> bool:
+    def _verify_artist_id(self, item: Dict[str, Any], result_artist_id,
+                          result_artist_name: Optional[str] = None) -> bool:
         """Verify that the result's artist ID matches the parent artist's stored Deezer ID.
+
         If mismatched, the album/track search is more specific (uses artist+title),
-        so we trust it and correct the parent artist's deezer_id."""
+        so we trust it and correct the parent artist's deezer_id — BUT only when
+        the result's artist *name* actually matches our parent artist. Without
+        that guard, a collaboration or compilation track (e.g. a track our
+        library credits to Jorja Smith that lives on Kendrick Lamar's curated
+        "Black Panther" album) would search up to an album whose Deezer primary
+        artist is someone else (Kendrick), and we'd stamp that wrong Deezer ID
+        onto our artist — corrupting it (and causing duplicate ids shared across
+        unrelated artists)."""
         parent_deezer_id = item.get('artist_deezer_id')
         if not parent_deezer_id:
             return True
@@ -290,6 +299,20 @@ class DeezerWorker:
             return True
 
         if str(result_artist_id) != str(parent_deezer_id):
+            # Guard: only correct when the album/track's primary artist is the
+            # SAME artist by name. A mismatch means it's a collab/compilation,
+            # not a stale-id correction.
+            parent_name = item.get('artist') or ''
+            if (result_artist_name and parent_name
+                    and not self._name_matches(parent_name, result_artist_name)):
+                logger.info(
+                    f"Skipping artist-ID correction from {item['type']} "
+                    f"'{item['name']}': result artist '{result_artist_name}' "
+                    f"≠ parent '{parent_name}' (collab/compilation, not a "
+                    f"correction)"
+                )
+                return True
+
             logger.info(
                 f"Artist ID correction from {item['type']} '{item['name']}': "
                 f"updating parent artist Deezer ID from {parent_deezer_id} to {result_artist_id}"
@@ -381,14 +404,18 @@ class DeezerWorker:
         result = self.client.search_artist(artist_name)
         if result:
             result_name = result.get('name', '')
-            if self._name_matches(artist_name, result_name):
+            ok, reason = accept_artist_match(
+                self.db, 'deezer_id', result.get('id'), artist_id,
+                artist_name, result_name,
+            )
+            if ok:
                 self._update_artist(artist_id, result)
                 self.stats['matched'] += 1
                 logger.info(f"Matched artist '{artist_name}' -> Deezer ID: {result.get('id')}")
             else:
                 self._mark_status('artist', artist_id, 'not_found')
                 self.stats['not_found'] += 1
-                logger.debug(f"Name mismatch for artist '{artist_name}' (got '{result_name}')")
+                logger.debug(f"Artist '{artist_name}' not matched: {reason}")
         else:
             self._mark_status('artist', artist_id, 'not_found')
             self.stats['not_found'] += 1
@@ -430,7 +457,8 @@ class DeezerWorker:
                 # Verify artist ID
                 result_artist = result.get('artist', {})
                 result_artist_id = result_artist.get('id') if result_artist else None
-                self._verify_artist_id(item, result_artist_id)
+                result_artist_name = result_artist.get('name') if result_artist else None
+                self._verify_artist_id(item, result_artist_id, result_artist_name)
 
                 # Fetch full album details for label, genres, explicit
                 deezer_album_id = result.get('id')
@@ -481,7 +509,8 @@ class DeezerWorker:
                 # Verify artist ID
                 result_artist = result.get('artist', {})
                 result_artist_id = result_artist.get('id') if result_artist else None
-                self._verify_artist_id(item, result_artist_id)
+                result_artist_name = result_artist.get('name') if result_artist else None
+                self._verify_artist_id(item, result_artist_id, result_artist_name)
 
                 # Fetch full track details for BPM
                 deezer_track_id = result.get('id')

core/discogs_worker.py

@@ -18,7 +18,7 @@ from datetime import datetime, timedelta
 from utils.logging_config import get_logger
 from database.music_database import MusicDatabase
 from core.discogs_client import DiscogsClient
-from core.worker_utils import interruptible_sleep, set_album_api_track_count
+from core.worker_utils import accept_artist_match, interruptible_sleep, set_album_api_track_count
 
 logger = get_logger("discogs_worker")
 
@@ -332,9 +332,13 @@ class DiscogsWorker:
             self.stats['not_found'] += 1
             return
 
-        # Find best match by name similarity
+        # Find best match by name similarity (skipping ids already claimed by
+        # a differently-named artist, so we don't create a shared/duplicate id).
         for result in results:
-            if self._name_matches(artist_name, result.name):
+            ok, reason = accept_artist_match(
+                self.db, 'discogs_id', result.id, artist_id, artist_name, result.name,
+            )
+            if ok:
                 # Fetch full artist detail (uses cache)
                 data = self.client._fetch_and_cache_artist(result.id)
                 if data:

core/discovery/manual_match.py

@@ -16,6 +16,10 @@ to test in isolation:
    overwrites the user's deliberate pick with whatever the auto-search
    ranks first, so manual matches are exempt regardless of provider
    drift. `is_drifted_for_redo` encapsulates the decision.
+
+3. *Should the Playlist Pipeline pre-scan (re)discover this track at all?*
+   — `should_rediscover` encapsulates that gate, with the manual match
+   checked FIRST so a leftover Wing It flag can't override the user's pick.
 """
 
 from __future__ import annotations
@@ -68,3 +72,49 @@ def is_drifted_for_redo(
         return False
     cached_provider = extra_data.get('provider', 'spotify')
     return cached_provider != active_provider
+
+
+def should_rediscover(extra_data: Optional[Dict[str, Any]]) -> bool:
+    """Return True when a mirrored track needs (re)discovery, False to skip it.
+
+    This is the gate the Playlist Pipeline pre-scan runs over every mirrored
+    track before discovering. The **ordering is the fix**: a manual match is
+    authoritative and is checked FIRST.
+
+    ``extra_data`` is *merged* on save (see ``update_mirrored_track_extra_data``),
+    so a track that was a Wing It stub and is then manually fixed still carries
+    ``wing_it_fallback: True`` alongside the new ``manual_match: True``. The old
+    pre-scan tested ``wing_it_fallback`` before ``manual_match``, so the stale
+    flag won and the pipeline re-discovered the track — silently reverting the
+    user's pick to Wing It. Checking ``manual_match`` first makes the fix stick.
+
+    Decision order:
+      * manual_match            -> skip   (authoritative; never re-discover)
+      * wing_it_fallback        -> redo   (stub — keep trying for a real match)
+      * discovered + complete   -> skip   (full metadata already stored)
+      * discovered + incomplete -> redo   (backfill track_number / album fields)
+      * unmatched_by_user       -> skip   (user deliberately removed the match)
+      * never discovered        -> redo   (first-time discovery)
+    """
+    extra = extra_data if isinstance(extra_data, dict) else {}
+
+    if extra.get('discovered'):
+        if extra.get('manual_match'):
+            return False
+        if extra.get('wing_it_fallback'):
+            return True
+        # Otherwise re-discover only when the stored match is missing the
+        # enriched fields (track_number + release_date/album.id) that older
+        # discoveries dropped via the Track dataclass.
+        matched = extra.get('matched_data')
+        matched = matched if isinstance(matched, dict) else {}
+        album = matched.get('album')
+        album = album if isinstance(album, dict) else {}
+        has_track_num = matched.get('track_number')
+        has_release = album.get('release_date')
+        has_album_id = album.get('id')
+        return not (has_track_num and (has_release or has_album_id))
+
+    if extra.get('unmatched_by_user'):
+        return False
+    return True

core/discovery/playlist.py

@@ -37,9 +37,35 @@ import time
 from dataclasses import dataclass
 from typing import Any, Callable
 
+from core.discovery.manual_match import should_rediscover
+
 logger = logging.getLogger(__name__)
 
 
+def _canonical_best_score(deps, title, artist, duration_ms, results):
+    """Score search results against the source track, trying the canonicalized
+    title/artist too and keeping the better confidence (#785).
+
+    YouTube playlists have their "Artist - Title" / channel decoration stripped
+    at ingest, but file/CSV-imported playlists keep raw titles — so a track
+    titled "Arctic Monkeys - Do I Wanna Know?" scored verbatim against the
+    library's "Do I Wanna Know?" never matched. canonical_source_track is
+    conservative (only strips an "<artist> - " prefix when it equals the
+    artist), so this can only ADD a better candidate, never weaken a match.
+    Returns (match, confidence)."""
+    match, confidence, _ = deps.discovery_score_candidates(title, artist, duration_ms, results)
+    try:
+        from core.text.source_title import canonical_source_track
+        canon_title, canon_artist = canonical_source_track(title or '', artist or '')
+    except Exception:
+        return match, confidence
+    if (canon_title, canon_artist) != (title, artist):
+        alt_match, alt_conf, _ = deps.discovery_score_candidates(canon_title, canon_artist, duration_ms, results)
+        if alt_match and alt_conf > confidence:
+            return alt_match, alt_conf
+    return match, confidence
+
+
 @dataclass
 class PlaylistDiscoveryDeps:
     """Bundle of cross-cutting deps the playlist discovery worker needs."""
@@ -121,44 +147,14 @@ def run_playlist_discovery_worker(playlists, automation_id=None, deps: PlaylistD
                         existing_extra = json.loads(track['extra_data']) if isinstance(track['extra_data'], str) else track['extra_data']
                     except (json.JSONDecodeError, TypeError):
                         pass
-                if existing_extra.get('discovered'):
-                    if existing_extra.get('wing_it_fallback'):
-                        # Wing It stub — always re-attempt to find a real match
-                        undiscovered_tracks.append(track)
-                    elif existing_extra.get('manual_match'):
-                        # User explicitly picked this match via the Fix popup.
-                        # Manual fixes are authoritative: they may lack
-                        # track_number / album.id / release_date (the Fix-popup
-                        # save shape is intentionally lean — search-result rows
-                        # don't include track_number, and the MBID-lookup flat
-                        # shape doesn't carry album.id), but re-running discovery
-                        # against the active source would overwrite the user's
-                        # deliberate pick with whatever the auto-search ranks
-                        # first. Skip — pipeline only re-discovers when the user
-                        # has cleared the match.
-                        pl_skipped += 1
-                        total_skipped += 1
-                    else:
-                        # Check if matched_data is complete — old discoveries may be missing
-                        # track_number/release_date due to the Track dataclass stripping them.
-                        # Re-discover these so the enriched pipeline fills in the gaps.
-                        md = existing_extra.get('matched_data', {})
-                        album = md.get('album', {})
-                        has_track_num = md.get('track_number')
-                        has_release = album.get('release_date') if isinstance(album, dict) else None
-                        has_album_id = album.get('id') if isinstance(album, dict) else None
-                        if has_track_num and (has_release or has_album_id):
-                            pl_skipped += 1
-                            total_skipped += 1
-                        else:
-                            # Incomplete discovery — re-discover to get full metadata
-                            undiscovered_tracks.append(track)
-                elif existing_extra.get('unmatched_by_user'):
-                    # User explicitly removed this match — respect their choice
+                # `should_rediscover` is the single source of truth for this
+                # gate (manual match checked FIRST so a stale Wing It flag can't
+                # revert a user's deliberate fix — see its docstring).
+                if should_rediscover(existing_extra):
+                    undiscovered_tracks.append(track)
+                else:
                     pl_skipped += 1
                     total_skipped += 1
-                else:
-                    undiscovered_tracks.append(track)
 
             if pl_skipped > 0:
                 deps.update_automation_progress(automation_id,
@@ -223,6 +219,20 @@ def run_playlist_discovery_worker(playlists, automation_id=None, deps: PlaylistD
                 except Exception:
                     search_queries = [f"{artist_name} {track_name}", track_name]
 
+                # #785: file/CSV playlists keep raw "Artist - Title" titles, so the
+                # queries above search for the artist prefix too. Also search the
+                # canonicalized title so the right candidates are actually returned
+                # (the scorer best-of then matches them).
+                try:
+                    from core.text.source_title import canonical_source_track
+                    _cq_title, _cq_artist = canonical_source_track(track_name, artist_name)
+                    if (_cq_title, _cq_artist) != (track_name, artist_name):
+                        for _q in (f"{_cq_artist} {_cq_title}", _cq_title):
+                            if _q not in search_queries:
+                                search_queries.append(_q)
+                except Exception as _cq_err:
+                    logger.debug("canonical search-query add failed: %s", _cq_err)
+
                 # Step 3: Search and score
                 best_match = None
                 best_confidence = 0.0
@@ -237,8 +247,8 @@ def run_playlist_discovery_worker(playlists, automation_id=None, deps: PlaylistD
                         if not results:
                             continue
 
-                        match, confidence, _ = deps.discovery_score_candidates(
-                            track_name, artist_name, duration_ms, results
+                        match, confidence = _canonical_best_score(
+                            deps, track_name, artist_name, duration_ms, results
                         )
 
                         if match and confidence > best_confidence:
@@ -259,8 +269,8 @@ def run_playlist_discovery_worker(playlists, automation_id=None, deps: PlaylistD
                         else:
                             extended = itunes_client_instance.search_tracks(query, limit=50)
                         if extended:
-                            match, confidence, _ = deps.discovery_score_candidates(
-                                track_name, artist_name, duration_ms, extended
+                            match, confidence = _canonical_best_score(
+                                deps, track_name, artist_name, duration_ms, extended
                             )
                             if match and confidence > best_confidence:
                                 best_confidence = confidence

core/discovery/sync.py

@@ -188,6 +188,22 @@ async def _database_only_find_track(spotify_track, candidate_pool=None):
                 server_source=active_server
             )
 
+            if not (db_track and confidence >= 0.80):
+                # #785: file/CSV playlists keep raw "Artist - Title" titles (unlike
+                # YouTube, cleaned at ingest), which don't match the clean library
+                # title. Retry with the canonical form (best-of, conservative).
+                try:
+                    from core.text.source_title import canonical_source_track
+                    _canon_title, _canon_artist = canonical_source_track(original_title, artist_name)
+                    if (_canon_title, _canon_artist) != (original_title, artist_name):
+                        _alt_track, _alt_conf = db.check_track_exists(
+                            _canon_title, _canon_artist,
+                            confidence_threshold=0.80, server_source=active_server)
+                        if _alt_track and _alt_conf > confidence:
+                            db_track, confidence = _alt_track, _alt_conf
+                except Exception as _canon_err:
+                    logger.debug("canonical retry failed: %s", _canon_err)
+
             if db_track and confidence >= 0.80:
                 logger.info(f"Database match: '{db_track.title}' (confidence: {confidence:.2f})")
                 if spotify_id:
@@ -508,7 +524,13 @@ def run_sync_task(
         # don't want persisted to app.log.
         _synced = getattr(result, 'synced_tracks', 0)
         logger.info(f"[PLAYLIST IMAGE] has_image={bool(playlist_image_url)}, synced_tracks={_synced}")
-        if playlist_image_url and _synced > 0:
+        # In reconcile mode the whole point (#792) is to NOT touch the playlist's
+        # existing image — pushing the source image here would re-clobber a
+        # user's custom poster every sync, the exact bug reconcile fixes. So skip
+        # the auto image push for reconcile (the playlist keeps its own art).
+        if sync_mode == 'reconcile':
+            logger.info("[PLAYLIST IMAGE] reconcile mode — preserving existing playlist image")
+        elif playlist_image_url and _synced > 0:
             try:
                 active_server = deps.config_manager.get_active_media_server()
                 logger.info(f"[PLAYLIST IMAGE] active_server={active_server}")

core/download_plugins/album_bundle.py

@@ -706,13 +706,19 @@ def resolve_reported_save_path(
 
 
 def copy_audio_files_atomically(
-    sources: Iterable[Path], staging_dir: Path,
+    sources: Iterable[Path], staging_dir: Path, remove_source: bool = False,
 ) -> list:
     """Convenience wrapper: pick a non-colliding staging path for
     each source, copy via ``atomic_copy_to_staging``. Returns the
     list of final destination paths (as strings). Files that fail
     to copy are logged and skipped; the caller decides what to do
-    with a partial result."""
+    with a partial result.
+
+    ``remove_source=True`` deletes each source AFTER it copies
+    successfully — used by the Soulseek bundle path so slskd's
+    completed downloads don't pile up in its download folder (#796).
+    Kept False for torrent/usenet, whose clients must retain the
+    originals (seeding / client-managed)."""
     staging_dir.mkdir(parents=True, exist_ok=True)
     out: list = []
     for src in sources:
@@ -720,6 +726,14 @@ def copy_audio_files_atomically(
         try:
             atomic_copy_to_staging(src, dest)
             out.append(str(dest))
+            if remove_source:
+                # Only after a verified copy — never lose data on a failed stage.
+                try:
+                    Path(src).unlink()
+                except FileNotFoundError:
+                    pass
+                except Exception as e:
+                    logger.debug("[album_bundle] Could not remove staged source %s: %s", src, e)
         except Exception as e:
             logger.warning("[album_bundle] Failed to stage %s -> %s: %s", src, dest, e)
     return out

core/downloads/candidates.py

@@ -326,6 +326,17 @@ def attempt_download_with_candidates(task_id, candidates, track, batch_id=None,
                             "task=%s username=%s filename=%s",
                             task_id, username, os.path.basename(filename),
                         )
+                    elif track_info and track_info.get('_skip_acoustid'):
+                        # Issue #797 — the album-download request had the
+                        # per-request "Skip AcoustID verification" toggle on.
+                        # Bypass only the AcoustID gate (same as a manual
+                        # pick); integrity + bit-depth still run.
+                        matched_downloads_context[context_key]['_skip_quarantine_check'] = 'acoustid'
+                        logger.info(
+                            "[Context] Skip-AcoustID toggle — bypassing AcoustID for "
+                            "task=%s filename=%s",
+                            task_id, os.path.basename(filename),
+                        )
 
                     logger.info(f"[Context] Set is_album_download: {is_album_context} (has clean data: {has_clean_spotify_data})")
                     logger.debug(f"[Debug] Context creation - track_info: {track_info is not None}, playlist_folder_mode: {track_info.get('_playlist_folder_mode', False) if track_info else False}")

core/downloads/master.py

@@ -347,6 +347,13 @@ def run_full_missing_tracks_process(batch_id, playlist_id, tracks_json, deps: Ma
         batch_playlist_name = 'Unknown Playlist'
         batch_playlist_id = playlist_id
         batch_source_playlist_ref = ''
+        # Issue #797 — per-request "Skip AcoustID verification" toggle from
+        # the album-download modal. When set, every track in this batch
+        # bypasses the AcoustID quarantine gate (the user has chosen to
+        # trust the metadata over fingerprint disagreement — useful for
+        # non-English artists whose native-script metadata AcoustID can't
+        # reconcile with the romanized request).
+        batch_skip_acoustid = False
         with tasks_lock:
             if batch_id in download_batches:
                 force_download_all = download_batches[batch_id].get('force_download_all', False)
@@ -362,6 +369,7 @@ def run_full_missing_tracks_process(batch_id, playlist_id, tracks_json, deps: Ma
                 batch_source_playlist_ref = (
                     download_batches[batch_id].get('source_playlist_ref') or ''
                 ).strip()
+                batch_skip_acoustid = bool(download_batches[batch_id].get('skip_acoustid', False))
 
         from core.downloads.playlist_folder import (
             resolve_playlist_folder_mode_for_batch,
@@ -1031,6 +1039,14 @@ def run_full_missing_tracks_process(batch_id, playlist_id, tracks_json, deps: Ma
                         logger.info(f"[Wishlist] Added album context for: '{track_info.get('name')}' -> '{album_ctx['name']}'")
 
 
+                # Issue #797 — propagate the batch-level "skip AcoustID"
+                # toggle onto each track so the per-track download context
+                # (built in core/downloads/candidates.py) can set the
+                # AcoustID quarantine bypass. Mirrors the _playlist_folder_mode
+                # threading pattern below.
+                if batch_skip_acoustid:
+                    track_info['_skip_acoustid'] = True
+
                 # Add playlist folder mode flag for sync page playlists and wishlist
                 # tracks tied to a mirrored playlist with organize_by_playlist enabled.
                 task_pl_folder_mode = batch_playlist_folder_mode

core/imports/pipeline.py

@@ -40,7 +40,6 @@ from core.imports.side_effects import (
     emit_track_downloaded,
     record_download_provenance,
     record_library_history_download,
-    record_retag_download,
     record_soulsync_library_entry,
 )
 from core.wishlist.resolution import check_and_remove_from_wishlist
@@ -892,13 +891,6 @@ def post_process_matched_download(context_key, context, file_path, runtime, meta
         record_download_provenance(context)
         record_soulsync_library_entry(context, artist_context, album_info)
 
-        try:
-            if not playlist_folder_mode:
-                completed_path = context.get('_final_processed_path', final_path)
-                record_retag_download(context, artist_context, album_info, completed_path)
-        except Exception as retag_err:
-            logger.error(f"[Post-Process] Retag data capture failed (non-fatal): {retag_err}")
-
         try:
             completed_path = context.get('_final_processed_path', final_path)
             batch_id_for_repair = context.get('batch_id')

core/imports/side_effects.py

@@ -676,88 +676,3 @@ def record_soulsync_library_entry(context: Dict[str, Any], artist_context: Dict[
             logger.info("[SoulSync Library] Added: %s / %s / %s", artist_name, album_name, track_name)
     except Exception as exc:
         logger.error("[SoulSync Library] Could not record library entry: %s", exc)
-
-
-def record_retag_download(context: Dict[str, Any], artist_context: Dict[str, Any], album_info: Dict[str, Any], final_path: str) -> None:
-    """Record a completed download for later re-tagging."""
-    try:
-        db = get_database()
-
-        context = normalize_import_context(context)
-        artist_context = get_import_context_artist(context) or (artist_context if isinstance(artist_context, dict) else {})
-        album_context = get_import_context_album(context)
-        track_info = get_import_track_info(context)
-        original_search = get_import_original_search(context)
-        source = get_import_source(context)
-        source_ids = get_import_source_ids(context)
-
-        artist_name = extract_artist_name(artist_context) or get_import_clean_artist(context, default="Unknown Artist")
-        is_album = album_info and album_info.get("is_album", False)
-        group_type = "album" if is_album else "single"
-        album_name = album_info.get("album_name", "") if album_info else get_import_clean_album(context, default=original_search.get("album", "Unknown"))
-
-        image_url = album_info.get("album_image_url") if album_info else None
-        if not image_url:
-            image_url = album_context.get("image_url", "")
-            if not image_url and album_context.get("images"):
-                images = album_context.get("images", [])
-                if images and isinstance(images[0], dict):
-                    image_url = images[0].get("url", "")
-
-        total_tracks = album_context.get("total_tracks", 1) if album_context else 1
-        release_date = album_context.get("release_date", "") if album_context else ""
-
-        spotify_album_id = None
-        itunes_album_id = None
-        if source == "spotify":
-            spotify_album_id = source_ids.get("album_id", "") or None
-        elif source == "itunes":
-            itunes_album_id = source_ids.get("album_id", "") or None
-
-        group_id = db.find_retag_group(artist_name, album_name)
-        if group_id is None:
-            group_id = db.add_retag_group(
-                group_type=group_type,
-                artist_name=artist_name,
-                album_name=album_name,
-                image_url=image_url,
-                spotify_album_id=spotify_album_id,
-                itunes_album_id=itunes_album_id,
-                total_tracks=total_tracks,
-                release_date=release_date,
-            )
-        if group_id is None:
-            return
-
-        track_number = album_info.get("track_number", 1) if album_info else (track_info.get("track_number", 1) or 1)
-        disc_number = original_search.get("disc_number") or (album_info.get("disc_number", 1) if album_info else track_info.get("disc_number", 1) or 1)
-        title = get_import_clean_title(
-            context,
-            album_info=album_info,
-            default=album_info.get("clean_track_name", "Unknown Track") if album_info else "Unknown Track",
-        )
-        file_format = os.path.splitext(str(final_path))[1].lstrip(".").lower()
-
-        source_track_id = None
-        itunes_track_id = None
-        if source == "spotify":
-            source_track_id = source_ids.get("track_id", "") or None
-        elif source == "itunes":
-            itunes_track_id = source_ids.get("track_id", "") or None
-
-        if not db.retag_track_exists(group_id, str(final_path)):
-            db.add_retag_track(
-                group_id=group_id,
-                track_number=track_number,
-                disc_number=disc_number,
-                title=title,
-                file_path=str(final_path),
-                file_format=file_format,
-                spotify_track_id=source_track_id,
-                itunes_track_id=itunes_track_id,
-            )
-            logger.info("[Retag] Recorded track for retag: '%s' in '%s'", title, album_name)
-
-        db.trim_retag_groups(100)
-    except Exception as exc:
-        logger.error("[Retag] Could not record track for retag: %s", exc)

core/itunes_worker.py

@@ -9,7 +9,7 @@ from datetime import datetime, timedelta
 from utils.logging_config import get_logger
 from database.music_database import MusicDatabase
 from core.itunes_client import iTunesClient
-from core.worker_utils import interruptible_sleep, set_album_api_track_count
+from core.worker_utils import accept_artist_match, interruptible_sleep, set_album_api_track_count
 from core.enrichment.manual_match_honoring import honor_stored_match
 
 logger = get_logger("itunes_worker")
@@ -393,7 +393,11 @@ class iTunesWorker:
             return
 
         for artist_obj in results:
-            if self._name_matches(artist_name, artist_obj.name):
+            ok, reason = accept_artist_match(
+                self.db, 'itunes_artist_id', artist_obj.id, artist_id,
+                artist_name, artist_obj.name,
+            )
+            if ok:
                 if not self._is_itunes_id(artist_obj.id):
                     logger.warning(f"Rejecting non-iTunes ID '{artist_obj.id}' for artist '{artist_name}'")
                     self._mark_status('artist', artist_id, 'error')

core/jellyfin_client.py

@@ -1605,6 +1605,80 @@ class JellyfinClient(MediaServerClient):
             logger.error(f"Error appending to Jellyfin playlist '{playlist_name}': {e}")
             return False
 
+    def reconcile_playlist(self, playlist_name: str, tracks) -> bool:
+        """In-place reconcile (#792): add missing + remove gone on the existing
+        playlist (POST/DELETE /Playlists/{id}/Items) so its poster, name, and Id
+        survive — no delete/recreate. Removal needs each entry's PlaylistItemId,
+        which we fetch from /Playlists/{id}/Items. Creates the playlist if
+        missing. Returns False so the caller can fall back to replace."""
+        if not self.ensure_connection():
+            return False
+        try:
+            import requests
+            from core.sync.playlist_edit import plan_playlist_reconcile
+            existing = self.get_playlist_by_name(playlist_name)
+            if not existing:
+                logger.info(f"Jellyfin reconcile: '{playlist_name}' doesn't exist — creating")
+                return self.create_playlist(playlist_name, tracks)
+
+            playlist_id = existing.id
+            # Entries carry both the track Id and the PlaylistItemId (entry id);
+            # removal is by EntryIds, not track Ids.
+            entries = []  # list of (track_id, entry_id) in playlist order
+            resp = self._make_request(f'/Playlists/{playlist_id}/Items', {'UserId': self.user_id})
+            if resp:
+                for item in resp.get('Items', []):
+                    tid = str(item.get('Id') or '')
+                    eid = str(item.get('PlaylistItemId') or '')
+                    if tid:
+                        entries.append((tid, eid))
+
+            current_ids = [tid for tid, _ in entries]
+            desired_ids = []
+            for t in tracks:
+                tid = (str(t.id) if hasattr(t, 'id') and t.id
+                       else str(t.get('Id') or t.get('id') or '') if isinstance(t, dict) else '')
+                if tid and self._is_valid_guid(tid):
+                    desired_ids.append(tid)
+
+            plan = plan_playlist_reconcile(current_ids, desired_ids)
+            hdr = {'X-Emby-Token': self.api_key}
+
+            if plan['add']:
+                for i in range(0, len(plan['add']), 100):
+                    batch = plan['add'][i:i + 100]
+                    r = requests.post(
+                        f"{self.base_url}/Playlists/{playlist_id}/Items",
+                        params={'Ids': ','.join(batch), 'UserId': self.user_id},
+                        headers=hdr, timeout=30,
+                    )
+                    if r.status_code not in (200, 204):
+                        logger.error(f"Jellyfin reconcile add failed: HTTP {r.status_code}")
+                        return False
+
+            if plan['remove']:
+                remove_set = set(plan['remove'])
+                entry_ids = [eid for tid, eid in entries if tid in remove_set and eid]
+                for i in range(0, len(entry_ids), 100):
+                    batch = entry_ids[i:i + 100]
+                    r = requests.delete(
+                        f"{self.base_url}/Playlists/{playlist_id}/Items",
+                        params={'EntryIds': ','.join(batch)},
+                        headers=hdr, timeout=30,
+                    )
+                    if r.status_code not in (200, 204):
+                        logger.error(f"Jellyfin reconcile remove failed: HTTP {r.status_code}")
+                        return False
+
+            logger.info(
+                f"Jellyfin reconcile '{playlist_name}': +{len(plan['add'])} / "
+                f"-{len(plan['remove'])} (playlist preserved)"
+            )
+            return True
+        except Exception as e:
+            logger.error(f"Error reconciling Jellyfin playlist '{playlist_name}': {e}")
+            return False
+
     def update_playlist(self, playlist_name: str, tracks) -> bool:
         """Update an existing playlist or create it if it doesn't exist"""
         if not self.ensure_connection():

core/library/embedded_id_reconcile.py

@@ -0,0 +1,415 @@
+"""Reconcile provider IDs embedded in audio files into the library DB.
+
+Enrichment workers (Spotify / iTunes / MusicBrainz / Deezer / Tidal /
+AudioDB / Genius / Last.fm) resolve each artist / album / track to a provider ID
+via API calls, gating their work queues on ``{provider}_match_status IS
+NULL``. But files that SoulSync (or MusicBrainz Picard) already tagged
+carry those IDs in their metadata. Reading them back and gap-filling the
+``{provider}_id`` + ``{provider}_match_status = 'matched'`` columns lets
+the workers skip the API lookup entirely — large API savings on an
+already-tagged library.
+
+Split into a PURE planning layer and a thin DB apply layer:
+
+- :func:`plan_reconcile` takes the tags read from ONE file (via
+  ``core.library.file_tags.read_embedded_tags``) plus the current IDs of
+  that file's track + its parent album + artist, and produces the list of
+  :class:`Fill` operations to perform. It is gap-fill only: a provider id
+  that already has a value is never planned for change; a DISAGREEING
+  embedded id is reported as a conflict instead.
+
+- :func:`apply_reconcile_plan` writes a plan, one guarded ``UPDATE`` per
+  id column: ``WHERE id = ? AND ({id_col} IS NULL OR {id_col} = '')``.
+  The guard makes the gap-fill ATOMIC — even if an enrichment worker
+  matched the same entity between the plan's read and this write, the
+  fill simply affects 0 rows instead of clobbering the worker's value.
+  Columns are introspected first so a schema version missing a provider's
+  columns is skipped, not errored.
+
+Scope note: the MusicBrainz *recording* (track) ID is intentionally not
+reconciled — on ID3 it lives in a ``UFID`` frame the shared reader
+doesn't surface and the Vorbis ``musicbrainz_trackid`` convention is
+format-ambiguous. MB *album* and *artist* IDs (which drive most worker
+API calls) ARE reconciled, as are the clean per-provider track/album/
+artist IDs of the other services.
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass, field
+from typing import Any, Dict, List, Optional
+
+# Each entry: (embedded-tag key from read_embedded_tags, entity, id column,
+# match-status column). The id columns mirror web_server._SERVICE_ID_COLUMNS;
+# they're spelled out here so this module stays importable without the Flask
+# app. Single-column providers (deezer/tidal/audiodb/genius) reuse one id
+# column across entity types — that's fine, fills are keyed by (entity, col).
+_RECONCILE_FIELDS = (
+    ('spotify_track_id',     'track',  'spotify_track_id',     'spotify_match_status'),
+    ('spotify_album_id',     'album',  'spotify_album_id',     'spotify_match_status'),
+    ('spotify_artist_id',    'artist', 'spotify_artist_id',    'spotify_match_status'),
+    ('itunes_track_id',      'track',  'itunes_track_id',      'itunes_match_status'),
+    ('itunes_album_id',      'album',  'itunes_album_id',      'itunes_match_status'),
+    ('itunes_artist_id',     'artist', 'itunes_artist_id',     'itunes_match_status'),
+    ('musicbrainz_albumid',  'album',  'musicbrainz_release_id', 'musicbrainz_match_status'),
+    ('musicbrainz_artistid', 'artist', 'musicbrainz_id',       'musicbrainz_match_status'),
+    ('deezer_track_id',      'track',  'deezer_id',            'deezer_match_status'),
+    ('deezer_album_id',      'album',  'deezer_id',            'deezer_match_status'),
+    ('deezer_artist_id',     'artist', 'deezer_id',            'deezer_match_status'),
+    ('tidal_track_id',       'track',  'tidal_id',             'tidal_match_status'),
+    ('tidal_album_id',       'album',  'tidal_id',             'tidal_match_status'),
+    ('tidal_artist_id',      'artist', 'tidal_id',             'tidal_match_status'),
+    ('audiodb_track_id',     'track',  'audiodb_id',           'audiodb_match_status'),
+    ('audiodb_album_id',     'album',  'audiodb_id',           'audiodb_match_status'),
+    ('audiodb_artist_id',    'artist', 'audiodb_id',           'audiodb_match_status'),
+    ('genius_track_id',      'track',  'genius_id',            'genius_match_status'),
+    # Last.fm embeds a single LASTFM_URL — sourced from get_track_info(), so it
+    # is the TRACK's url. Map to tracks.lastfm_url only (artist/album last.fm
+    # urls are different urls and aren't carried in the file).
+    ('lastfm_url',           'track',  'lastfm_url',           'lastfm_match_status'),
+)
+
+_ENTITIES = ('track', 'album', 'artist')
+_ENTITY_TABLE = {'track': 'tracks', 'album': 'albums', 'artist': 'artists'}
+
+
+@dataclass(frozen=True)
+class Fill:
+    """One provider-id column to gap-fill on one entity."""
+    entity: str          # 'track' | 'album' | 'artist'
+    id_column: str       # e.g. 'spotify_artist_id'
+    status_column: str   # e.g. 'spotify_match_status'
+    value: str           # the embedded id to write
+
+
+@dataclass
+class ReconcilePlan:
+    """The outcome of planning one file against its current DB rows.
+
+    ``fills`` are the gap-fill operations to apply (empty id columns only).
+    ``already_present`` counts embedded ids that matched a value already
+    stored (no-op). ``conflicts`` lists embedded ids that DISAGREE with a
+    stored value — never applied, surfaced for review.
+    """
+
+    fills: List[Fill] = field(default_factory=list)
+    already_present: int = 0
+    conflicts: List[Dict[str, str]] = field(default_factory=list)
+
+    @property
+    def filled(self) -> int:
+        return len(self.fills)
+
+    @property
+    def has_updates(self) -> bool:
+        return bool(self.fills)
+
+    def fills_for(self, entity: str) -> List[Fill]:
+        return [f for f in self.fills if f.entity == entity]
+
+
+@dataclass
+class ReconcileApplied:
+    """Counts from actually writing a plan (based on real ``rowcount``)."""
+    rows_updated: int = 0    # distinct entity rows touched
+    ids_filled: int = 0      # id columns that actually landed (guard passed)
+
+
+def _clean(value: Any) -> Optional[str]:
+    """Normalise a tag/column value to a non-empty stripped string or None."""
+    if value is None:
+        return None
+    s = str(value).strip()
+    return s or None
+
+
+def plan_reconcile(
+    embedded_tags: Optional[Dict[str, Any]],
+    current_ids: Optional[Dict[str, Dict[str, Any]]],
+) -> ReconcilePlan:
+    """Plan which provider-ID columns to gap-fill from one file's tags.
+
+    Args:
+        embedded_tags: the ``tags`` dict from ``read_embedded_tags`` (flat
+            ``friendly_key -> value``). ``None`` / empty yields an empty plan.
+        current_ids: ``{'track': {...}, 'album': {...}, 'artist': {...}}``
+            where each inner dict holds the entity's CURRENT column values
+            (at minimum the id columns this module touches). Missing
+            entities / keys are treated as empty (eligible to fill).
+
+    Returns:
+        A :class:`ReconcilePlan`. Gap-fill only — an id column with any
+        existing value is never planned; a disagreeing embedded id is
+        recorded in ``conflicts``.
+    """
+    plan = ReconcilePlan()
+    tags = embedded_tags or {}
+    current = current_ids or {}
+    queued: Dict[tuple, str] = {}  # (entity, id_col) already queued this pass
+
+    for embedded_key, entity, id_col, status_col in _RECONCILE_FIELDS:
+        new_val = _clean(tags.get(embedded_key))
+        if not new_val:
+            continue
+
+        row = current.get(entity) or {}
+        existing = _clean(row.get(id_col))
+        if existing is not None:
+            if existing != new_val:
+                plan.conflicts.append({
+                    'entity': entity, 'column': id_col,
+                    'existing': existing, 'embedded': new_val,
+                })
+            else:
+                plan.already_present += 1
+            continue
+
+        key = (entity, id_col)
+        if key in queued:
+            # A single-column provider already queued this id col this pass.
+            if queued[key] != new_val:
+                plan.conflicts.append({
+                    'entity': entity, 'column': id_col,
+                    'existing': queued[key], 'embedded': new_val,
+                })
+            continue
+
+        queued[key] = new_val
+        plan.fills.append(Fill(entity, id_col, status_col, new_val))
+
+    return plan
+
+
+@dataclass
+class TrackReconcileResult:
+    """Outcome of reconciling one track row against its file's tags."""
+    applied: 'ReconcileApplied'
+    conflicts: int = 0
+    readable: bool = True   # False when the file's tags couldn't be read
+
+
+def reconcile_track_row(
+    cursor,
+    track_row: Dict[str, Any],
+    album_map: Dict[str, Dict[str, Any]],
+    artist_map: Dict[str, Dict[str, Any]],
+    embedded_tags: Optional[Dict[str, Any]],
+) -> TrackReconcileResult:
+    """Reconcile one track row + its parent album/artist against one file.
+
+    Pure orchestration over :func:`plan_reconcile` / :func:`apply_reconcile_plan`,
+    extracted so the per-track logic (id extraction, plan→apply chaining,
+    keeping the in-memory parent maps fresh for sibling tracks) is testable
+    without the Flask job. ``embedded_tags`` is the ``tags`` dict from
+    ``read_embedded_tags`` (``None`` => unreadable file).
+
+    ``album_map`` / ``artist_map`` map entity-id -> current column dict; this
+    function UPDATES them in place with any fills it applies so a later track
+    on the same album/artist sees the value and doesn't re-plan it. (DB safety
+    is the guarded UPDATE in apply, never these maps.)
+    """
+    if not embedded_tags:
+        return TrackReconcileResult(ReconcileApplied(), 0, readable=False)
+
+    album_id = str(track_row['album_id']) if track_row.get('album_id') is not None else None
+    artist_id = str(track_row['artist_id']) if track_row.get('artist_id') is not None else None
+
+    plan = plan_reconcile(embedded_tags, {
+        'track': track_row,
+        'album': album_map.get(album_id, {}) if album_id else {},
+        'artist': artist_map.get(artist_id, {}) if artist_id else {},
+    })
+    applied = apply_reconcile_plan(cursor, {
+        'track': track_row.get('id'), 'album': album_id, 'artist': artist_id,
+    }, plan)
+
+    if album_id:
+        for f in plan.fills_for('album'):
+            album_map.setdefault(album_id, {})[f.id_column] = f.value
+    if artist_id:
+        for f in plan.fills_for('artist'):
+            artist_map.setdefault(artist_id, {})[f.id_column] = f.value
+
+    return TrackReconcileResult(applied, len(plan.conflicts), readable=True)
+
+
+@dataclass
+class ReconcileTotals:
+    """Accumulated counts over a reconcile run."""
+    total: int = 0
+    processed: int = 0
+    ids_filled: int = 0
+    entities_updated: int = 0
+    conflicts: int = 0
+    unreadable: int = 0
+
+
+def _load_missing_rows(cursor, ids, table, target: Dict[str, Dict[str, Any]]) -> None:
+    """Load any not-yet-cached entity rows for ``ids`` into ``target`` in place.
+
+    Ids with no row get an empty dict so they're never re-queried. Chunked to
+    keep the IN clause bounded.
+    """
+    missing = [i for i in {x for x in ids if x} if i not in target]
+    for start in range(0, len(missing), 500):
+        chunk = missing[start:start + 500]
+        ph = ','.join('?' * len(chunk))
+        cursor.execute(f"SELECT * FROM {table} WHERE id IN ({ph})", chunk)
+        for r in cursor.fetchall():
+            target[str(r['id'])] = dict(r)
+    for i in missing:
+        target.setdefault(i, {})  # mark absent → don't re-query
+
+
+def reconcile_library(
+    conn,
+    read_tags,
+    track_ids=None,
+    page_size: int = 500,
+    on_progress=None,
+    should_stop=None,
+) -> ReconcileTotals:
+    """Gap-fill embedded provider IDs into the DB for a set of tracks.
+
+    Shared orchestration used by both the manual backfill job and the
+    auto-reconcile hook on library scans. Pages the track list (bounded
+    memory), lazily loads only the parent album/artist rows actually
+    referenced (cheap when scoped to a handful of new tracks), and commits
+    per page so concurrent enrichment workers aren't starved of the write
+    lock.
+
+    Args:
+        conn: open DB connection; this function commits per page.
+        read_tags: callable ``(file_path) -> tags dict | None``. The caller
+            injects path resolution + ``read_embedded_tags`` so this module
+            stays free of Flask / docker-path concerns. ``None`` => unreadable.
+        track_ids: iterable of track ids to reconcile, or ``None`` for every
+            track that has a ``file_path``.
+        page_size: rows materialised per page.
+        on_progress: optional ``(totals, current_title) -> None`` after each
+            track (for live UI).
+        should_stop: optional ``() -> bool`` checked between tracks/pages to
+            abort early.
+
+    Returns:
+        :class:`ReconcileTotals`.
+    """
+    from utils.logging_config import get_logger
+    logger = get_logger("library.reconcile")
+
+    totals = ReconcileTotals()
+    cur = conn.cursor()
+
+    if track_ids is None:
+        cur.execute("SELECT id FROM tracks WHERE file_path IS NOT NULL AND TRIM(file_path) != ''")
+        ids = [str(r[0]) for r in cur.fetchall()]
+    else:
+        ids = [str(t) for t in track_ids if t is not None]
+    totals.total = len(ids)
+
+    album_map: Dict[str, Dict[str, Any]] = {}
+    artist_map: Dict[str, Dict[str, Any]] = {}
+
+    for start in range(0, len(ids), page_size):
+        if should_stop and should_stop():
+            break
+        page = ids[start:start + page_size]
+        ph = ','.join('?' * len(page))
+        cur.execute(f"SELECT * FROM tracks WHERE id IN ({ph})", page)
+        rows = [dict(r) for r in cur.fetchall()]
+
+        _load_missing_rows(cur, [str(r['album_id']) for r in rows if r.get('album_id') is not None],
+                           'albums', album_map)
+        _load_missing_rows(cur, [str(r['artist_id']) for r in rows if r.get('artist_id') is not None],
+                           'artists', artist_map)
+
+        for tr in rows:
+            if should_stop and should_stop():
+                break
+            title = tr.get('title') or '?'
+            try:
+                tags = read_tags(tr.get('file_path'))
+                result = reconcile_track_row(cur, tr, album_map, artist_map, tags)
+                if not result.readable:
+                    totals.unreadable += 1
+                else:
+                    totals.ids_filled += result.applied.ids_filled
+                    totals.entities_updated += result.applied.rows_updated
+                    totals.conflicts += result.conflicts
+            except Exception as e:
+                logger.debug("reconcile: skipped track %s: %s", tr.get('id'), e)
+                totals.unreadable += 1
+            finally:
+                totals.processed += 1
+                if on_progress:
+                    on_progress(totals, title)
+
+        conn.commit()
+
+    return totals
+
+
+def _existing_columns(cursor, table: str) -> set:
+    """Return the set of column names on ``table`` (migration-safe guard)."""
+    cursor.execute(f"PRAGMA table_info({table})")
+    return {r[1] for r in cursor.fetchall()}
+
+
+def apply_reconcile_plan(cursor, entity_ids: Dict[str, Any], plan: ReconcilePlan) -> ReconcileApplied:
+    """Apply a :class:`ReconcilePlan` to the DB via ``cursor``.
+
+    Each fill is a single guarded ``UPDATE``:
+
+        UPDATE {table} SET {id}=?, {status}='matched', {attempted}=now
+        WHERE id=? AND ({id} IS NULL OR {id}='')
+
+    The ``id IS NULL OR id=''`` guard makes the gap-fill atomic: if the
+    column became non-empty between the plan's read and now (an enrichment
+    worker matched it concurrently), the UPDATE affects 0 rows and the
+    worker's value is preserved. Only columns that exist on the table are
+    written (introspected + cached per call), so a schema missing a
+    provider's columns is silently skipped.
+
+    Args:
+        cursor: an open DB cursor (caller owns the transaction/commit).
+        entity_ids: ``{'track': id, 'album': id, 'artist': id}``. An entity
+            with no id is skipped.
+
+    Returns:
+        A :class:`ReconcileApplied` with counts derived from real rowcounts.
+    """
+    result = ReconcileApplied()
+    touched: set = set()
+    col_cache: Dict[str, set] = {}
+
+    for fill in plan.fills:
+        ent_id = entity_ids.get(fill.entity)
+        if ent_id is None or ent_id == '':
+            continue
+        table = _ENTITY_TABLE[fill.entity]
+        if table not in col_cache:
+            col_cache[table] = _existing_columns(cursor, table)
+        cols = col_cache[table]
+        if fill.id_column not in cols:
+            continue
+
+        assignments = [f"{fill.id_column} = ?"]
+        values: List[Any] = [fill.value]
+        if fill.status_column in cols:
+            assignments.append(f"{fill.status_column} = ?")
+            values.append('matched')
+            attempted = fill.status_column.replace('_match_status', '_last_attempted')
+            if attempted in cols:
+                assignments.append(f"{attempted} = CURRENT_TIMESTAMP")
+
+        cursor.execute(
+            f"UPDATE {table} SET {', '.join(assignments)} "
+            f"WHERE id = ? AND ({fill.id_column} IS NULL OR {fill.id_column} = '')",
+            values + [str(ent_id)],
+        )
+        if cursor.rowcount:
+            result.ids_filled += 1
+            touched.add((fill.entity, str(ent_id)))
+
+    result.rows_updated = len(touched)
+    return result

core/library/retag.py

@@ -1,350 +0,0 @@
-"""Library retag worker.
-
-`execute_retag(group_id, album_id, deps)` rewrites tags + filenames for a
-group of audio files when the user has matched them to a different
-album. The worker:
-
-1. Fetches album + track metadata for the new `album_id` (Spotify or
-   iTunes — Spotify client transparently falls back).
-2. Loads existing files in the retag group from the DB.
-3. Matches each existing track to a new Spotify track:
-   - Priority 1: same disc + track number.
-   - Priority 2: title similarity >= 0.6 (SequenceMatcher).
-4. For each matched pair:
-   - Re-write metadata tags via `_enhance_file_metadata`.
-   - Compute the new path via `_build_final_path_for_track` and move
-     the audio file (plus .lrc / .txt sidecars) if the path changes.
-   - Drop an orphaned cover.jpg if it's left in an empty directory.
-   - Clean up empty parent directories left behind.
-   - Download the new cover art into the new album dir.
-5. Update the retag group record with the new artist / album / image /
-   total_tracks / release_date and the appropriate Spotify-or-iTunes
-   album ID.
-6. Mark the retag state 'finished' (or 'error' on exception).
-
-The original mutated `retag_state` as a module global. Here it's exposed
-through the `RetagDeps` proxy as a Python property so the lifted body
-keeps the same `name[key] = value` syntax. The property setter rebinds
-the web_server.py reference if needed (currently the function only
-mutates in place via .update() and key assignment, so the setter never
-fires).
-"""
-
-from __future__ import annotations
-
-import logging
-import os
-import traceback
-from dataclasses import dataclass
-from difflib import SequenceMatcher
-from typing import Any, Callable, Optional
-
-logger = logging.getLogger(__name__)
-
-
-@dataclass
-class RetagDeps:
-    """Bundle of cross-cutting deps the retag worker needs.
-
-    `retag_state` is exposed as a property so the lifted body keeps
-    `name[key] = value` / `name.update(...)` syntax.
-    """
-    config_manager: Any
-    retag_lock: Any  # threading.Lock
-    spotify_client: Any
-    get_audio_quality_string: Callable[[str], str]
-    enhance_file_metadata: Callable
-    build_final_path_for_track: Callable
-    safe_move_file: Callable
-    cleanup_empty_directories: Callable
-    download_cover_art: Callable
-    docker_resolve_path: Callable[[str], str]
-    _get_retag_state: Callable[[], dict]
-    _set_retag_state: Callable[[dict], None]
-    get_database: Callable[[], Any]
-    # Discord report (Netti93) — retag was clearing the LYRICS / USLT
-    # tag without rewriting it, while the download pipeline calls
-    # `generate_lrc_file` after enrichment to refetch + embed lyrics.
-    # Injected here so retag mirrors the same post-enrichment step.
-    # Optional for backward compat with any test caller that builds
-    # RetagDeps without the new field — empty default no-ops the call.
-    generate_lrc_file: Optional[Callable] = None
-
-    @property
-    def retag_state(self) -> dict:
-        return self._get_retag_state()
-
-    @retag_state.setter
-    def retag_state(self, value: dict) -> None:
-        self._set_retag_state(value)
-
-
-def execute_retag(group_id, album_id, deps: RetagDeps):
-    """Execute a retag operation: re-tag files in a group with metadata from a new album match."""
-    try:
-        with deps.retag_lock:
-            deps.retag_state.update({
-                "status": "running",
-                "phase": "Fetching album metadata...",
-                "progress": 0,
-                "current_track": "",
-                "total_tracks": 0,
-                "processed": 0,
-                "error_message": ""
-            })
-
-        # 1. Fetch new album metadata from Spotify/iTunes
-        album_data = deps.spotify_client.get_album(album_id)
-        if not album_data:
-            raise ValueError(f"Could not fetch album data for ID: {album_id}")
-
-        album_tracks_response = deps.spotify_client.get_album_tracks(album_id)
-        if not album_tracks_response:
-            raise ValueError(f"Could not fetch album tracks for ID: {album_id}")
-
-        album_tracks_items = album_tracks_response.get('items', [])
-
-        # Extract artist info
-        album_artists = album_data.get('artists', [])
-        new_artist = album_artists[0] if album_artists else {'name': 'Unknown Artist', 'id': ''}
-        # Ensure artist is a dict with expected fields
-        if not isinstance(new_artist, dict):
-            new_artist = {'name': str(new_artist), 'id': ''}
-        new_album_name = album_data.get('name', 'Unknown Album')
-        new_images = album_data.get('images', [])
-        new_image_url = new_images[0]['url'] if new_images else None
-        new_release_date = album_data.get('release_date', '')
-        total_tracks = album_data.get('total_tracks', len(album_tracks_items))
-
-        # Build spotify track list
-        spotify_tracks = []
-        for item in album_tracks_items:
-            track_artists = item.get('artists', [])
-            spotify_tracks.append({
-                'name': item.get('name', ''),
-                'track_number': item.get('track_number', 1),
-                'disc_number': item.get('disc_number', 1),
-                'id': item.get('id', ''),
-                'artists': track_artists,
-                'duration_ms': item.get('duration_ms', 0)
-            })
-
-        total_discs = max((t['disc_number'] for t in spotify_tracks), default=1)
-
-        # 2. Load existing tracks for this group
-        db = deps.get_database()
-        existing_tracks = db.get_retag_tracks(group_id)
-        if not existing_tracks:
-            raise ValueError(f"No tracks found for retag group {group_id}")
-
-        with deps.retag_lock:
-            deps.retag_state['total_tracks'] = len(existing_tracks)
-            deps.retag_state['phase'] = "Matching tracks..."
-
-        # 3. Match existing files to new tracklist
-        matched_pairs = []
-        for existing_track in existing_tracks:
-            best_match = None
-            best_score = 0
-
-            # Priority 1: Match by track number
-            for st in spotify_tracks:
-                if (st['track_number'] == existing_track.get('track_number') and
-                        st['disc_number'] == existing_track.get('disc_number', 1)):
-                    best_match = st
-                    best_score = 1.0
-                    break
-
-            # Priority 2: Match by title similarity
-            if not best_match:
-                from difflib import SequenceMatcher
-                existing_title = (existing_track.get('title') or '').lower().strip()
-                for st in spotify_tracks:
-                    st_title = (st.get('name') or '').lower().strip()
-                    score = SequenceMatcher(None, existing_title, st_title).ratio()
-                    if score > best_score and score > 0.6:
-                        best_score = score
-                        best_match = st
-
-            if best_match:
-                matched_pairs.append((existing_track, best_match))
-            else:
-                logger.warning(f"[Retag] No match found for track: '{existing_track.get('title')}'")
-                matched_pairs.append((existing_track, None))
-
-        with deps.retag_lock:
-            deps.retag_state['phase'] = "Retagging files..."
-
-        # 4. Retag each matched track
-        for existing_track, matched_spotify in matched_pairs:
-            current_file_path = existing_track.get('file_path', '')
-            track_title = matched_spotify['name'] if matched_spotify else existing_track.get('title', 'Unknown')
-
-            with deps.retag_lock:
-                deps.retag_state['current_track'] = track_title
-
-            if not matched_spotify:
-                with deps.retag_lock:
-                    deps.retag_state['processed'] += 1
-                    deps.retag_state['progress'] = int(deps.retag_state['processed'] / deps.retag_state['total_tracks'] * 100)
-                continue
-
-            # Verify file exists
-            if not os.path.exists(current_file_path):
-                logger.warning(f"[Retag] File not found, skipping: {current_file_path}")
-                with deps.retag_lock:
-                    deps.retag_state['processed'] += 1
-                    deps.retag_state['progress'] = int(deps.retag_state['processed'] / deps.retag_state['total_tracks'] * 100)
-                continue
-
-            # Build synthetic context for _enhance_file_metadata
-            track_artists = matched_spotify.get('artists', [])
-            context = {
-                'original_search_result': {
-                    'spotify_clean_title': matched_spotify['name'],
-                    'spotify_clean_album': new_album_name,
-                    'track_number': matched_spotify['track_number'],
-                    'disc_number': matched_spotify.get('disc_number', 1),
-                    'artists': track_artists,
-                    'title': matched_spotify['name']
-                },
-                'spotify_album': {
-                    'id': album_id,
-                    'name': new_album_name,
-                    'release_date': new_release_date,
-                    'total_tracks': total_tracks,
-                    'image_url': new_image_url,
-                    'total_discs': total_discs
-                },
-                'track_info': {'id': matched_spotify['id']},
-                'spotify_artist': new_artist,
-                '_audio_quality': deps.get_audio_quality_string(current_file_path) or ''
-            }
-
-            album_info = {
-                'is_album': total_tracks > 1,
-                'album_name': new_album_name,
-                'track_number': matched_spotify['track_number'],
-                'disc_number': matched_spotify.get('disc_number', 1),
-                'clean_track_name': matched_spotify['name'],
-                'album_image_url': new_image_url
-            }
-
-            # Re-write metadata tags
-            try:
-                deps.enhance_file_metadata(current_file_path, context, new_artist, album_info)
-                logger.info(f"[Retag] Re-tagged: '{track_title}'")
-            except Exception as meta_err:
-                logger.error(f"[Retag] Metadata write failed for '{track_title}': {meta_err}")
-
-            # Discord report (Netti93) — `enhance_file_metadata` clears
-            # ALL tags (incl. USLT lyrics) and rewrites only the source
-            # metadata. The download pipeline calls `generate_lrc_file`
-            # after enrichment to refetch + embed lyrics — retag was
-            # missing that step and dropped the LYRICS tag with no
-            # rewrite. Mirroring the download path's post-enrichment
-            # step. Same args, same `lrclib_enabled` config gate, same
-            # idempotency (skip when sidecar already present).
-            if deps.generate_lrc_file:
-                try:
-                    deps.generate_lrc_file(current_file_path, context, new_artist, album_info)
-                except Exception as lrc_err:
-                    logger.debug("[Retag] generate_lrc_file failed for '%s': %s", track_title, lrc_err)
-
-            # Compute new path and move if different
-            file_ext = os.path.splitext(current_file_path)[1]
-            try:
-                new_path, _ = deps.build_final_path_for_track(context, new_artist, album_info, file_ext)
-
-                if os.path.normpath(current_file_path) != os.path.normpath(new_path):
-                    logger.info(f"[Retag] Moving '{os.path.basename(current_file_path)}' -> '{new_path}'")
-                    old_dir = os.path.dirname(current_file_path)
-                    os.makedirs(os.path.dirname(new_path), exist_ok=True)
-                    deps.safe_move_file(current_file_path, new_path)
-
-                    # Move lyrics sidecar file alongside audio file if it exists
-                    for lyrics_ext in ('.lrc', '.txt'):
-                        old_lyrics = os.path.splitext(current_file_path)[0] + lyrics_ext
-                        if os.path.exists(old_lyrics):
-                            new_lyrics = os.path.splitext(new_path)[0] + lyrics_ext
-                            try:
-                                deps.safe_move_file(old_lyrics, new_lyrics)
-                                logger.info(f"[Retag] Moved {lyrics_ext} file alongside audio")
-                            except Exception as lrc_err:
-                                logger.error(f"[Retag] Failed to move {lyrics_ext} file: {lrc_err}")
-
-                    # Remove old cover.jpg if directory changed and old dir is now empty of audio
-                    new_dir = os.path.dirname(new_path)
-                    if os.path.normpath(old_dir) != os.path.normpath(new_dir):
-                        old_cover = os.path.join(old_dir, 'cover.jpg')
-                        if os.path.exists(old_cover):
-                            # Check if any audio files remain in old directory
-                            audio_exts = {'.flac', '.mp3', '.m4a', '.ogg', '.opus', '.wav', '.aac'}
-                            remaining_audio = [f for f in os.listdir(old_dir)
-                                               if os.path.splitext(f)[1].lower() in audio_exts]
-                            if not remaining_audio:
-                                try:
-                                    os.remove(old_cover)
-                                    logger.warning("[Retag] Removed orphaned cover.jpg from old directory")
-                                except Exception as e:
-                                    logger.debug("remove orphaned cover failed: %s", e)
-
-                    # Cleanup old empty directories
-                    transfer_dir = deps.docker_resolve_path(deps.config_manager.get('soulseek.transfer_path', './Transfer'))
-                    deps.cleanup_empty_directories(transfer_dir, current_file_path)
-
-                    # Update DB record
-                    db.update_retag_track_path(existing_track['id'], str(new_path))
-                    current_file_path = new_path
-                else:
-                    logger.warning(f"[Retag] Path unchanged for '{track_title}', no move needed")
-            except Exception as move_err:
-                logger.error(f"[Retag] Path/move failed for '{track_title}': {move_err}")
-
-            # Download cover art to album directory
-            try:
-                deps.download_cover_art(album_info, os.path.dirname(current_file_path), context)
-            except Exception as cover_err:
-                logger.error(f"[Retag] Cover art download failed: {cover_err}")
-
-            with deps.retag_lock:
-                deps.retag_state['processed'] += 1
-                deps.retag_state['progress'] = int(deps.retag_state['processed'] / deps.retag_state['total_tracks'] * 100)
-
-        # 5. Update the retag group record with new metadata
-        update_kwargs = {
-            'artist_name': new_artist.get('name', 'Unknown Artist'),
-            'album_name': new_album_name,
-            'image_url': new_image_url,
-            'total_tracks': total_tracks,
-            'release_date': new_release_date
-        }
-        # Set the correct ID field based on Spotify vs iTunes
-        if str(album_id).isdigit():
-            update_kwargs['itunes_album_id'] = album_id
-            update_kwargs['spotify_album_id'] = None
-        else:
-            update_kwargs['spotify_album_id'] = album_id
-            update_kwargs['itunes_album_id'] = None
-
-        db.update_retag_group(group_id, **update_kwargs)
-
-        with deps.retag_lock:
-            deps.retag_state.update({
-                "status": "finished",
-                "phase": "Retag complete!",
-                "progress": 100,
-                "current_track": ""
-            })
-        logger.info(f"[Retag] Retag operation complete for group {group_id}")
-
-    except Exception as e:
-        import traceback
-        logger.error(f"[Retag] Error during retag: {e}")
-        logger.error(traceback.format_exc())
-        with deps.retag_lock:
-            deps.retag_state.update({
-                "status": "error",
-                "phase": "Error",
-                "error_message": str(e)
-            })

core/library/retag_planner.py

@@ -0,0 +1,218 @@
+"""Pure planning logic for the library re-tag job.
+
+Given a source album's metadata + tracklist and the library's tracks (with their
+*current* file tags), this works out — per track — exactly which tags would
+change (the dry-run diff the finding shows) and the ``db_data`` payload to feed
+``core.tag_writer.write_tags_to_file`` at apply time.
+
+No file IO, no network, no DB: the job feeds in current tags + fetched source
+data, so all the matching/diff logic stays unit-testable. Tags are only ever
+ADDED/overwritten per-field — never a full tag-block wipe.
+"""
+
+from __future__ import annotations
+
+import re
+from difflib import SequenceMatcher
+from typing import Any, Dict, List, Optional, Tuple
+
+# Fields this job manages. Keys are the internal/display names; the diff and the
+# write payload are both built from these.
+MANAGED_FIELDS = ('title', 'artist', 'album', 'year', 'genre', 'track_number', 'disc_number')
+
+# Modes: overwrite everything the source provides, or only fill blanks.
+MODE_OVERWRITE = 'overwrite'
+MODE_FILL_MISSING = 'fill_missing'
+
+
+def _get(obj: Any, *keys: str, default=None):
+    """First non-empty value across keys, from a dict or an object."""
+    for k in keys:
+        v = obj.get(k) if isinstance(obj, dict) else getattr(obj, k, None)
+        if v not in (None, ''):
+            return v
+    return default
+
+
+def _first_artist(obj: Any) -> str:
+    arts = _get(obj, 'artists', 'artist', 'artist_name')
+    if isinstance(arts, list) and arts:
+        a0 = arts[0]
+        return ((a0.get('name') if isinstance(a0, dict) else str(a0)) or '').strip()
+    if isinstance(arts, dict):
+        return (arts.get('name') or '').strip()
+    return str(arts).strip() if arts else ''
+
+
+def _genres_list(obj: Any) -> List[str]:
+    g = _get(obj, 'genres', 'genre')
+    if isinstance(g, list):
+        return [str(x).strip() for x in g if str(x).strip()]
+    if isinstance(g, str) and g.strip():
+        return [p.strip() for p in g.split(',') if p.strip()]
+    return []
+
+
+def _year(obj: Any) -> str:
+    v = _get(obj, 'year', 'release_date', 'date')
+    if not v:
+        return ''
+    m = re.search(r'\d{4}', str(v))
+    return m.group(0) if m else ''
+
+
+def _int_or_none(v) -> Optional[int]:
+    try:
+        return int(v)
+    except (TypeError, ValueError):
+        return None
+
+
+def _norm_title(s: Any) -> str:
+    s = (s or '')
+    s = s.lower() if isinstance(s, str) else str(s).lower()
+    s = re.sub(r'[\(\[].*?[\)\]]', ' ', s)
+    s = re.sub(r'[^a-z0-9]+', ' ', s)
+    return ' '.join(s.split())
+
+
+def match_source_tracks(
+    source_tracks: List[Any],
+    library_tracks: List[Dict[str, Any]],
+    title_threshold: float = 0.6,
+) -> List[Tuple[Dict[str, Any], Optional[Any]]]:
+    """Pair each library track to a source track.
+
+    Disc+track number is authoritative; falls back to title similarity. A source
+    track is consumed once. Returns ``[(library_track, source_track_or_None)]``
+    in library order, so unmatched library tracks surface as ``None``.
+    """
+    by_pos: Dict[Tuple[int, int], int] = {}
+    for i, st in enumerate(source_tracks):
+        t = _int_or_none(_get(st, 'track_number'))
+        if t is None:
+            continue
+        d = _int_or_none(_get(st, 'disc_number', default=1)) or 1
+        by_pos.setdefault((d, t), i)
+
+    used: set = set()
+    pairs: List[Tuple[Dict[str, Any], Optional[Any]]] = []
+    for lt in library_tracks:
+        t = _int_or_none(lt.get('track_number'))
+        d = _int_or_none(lt.get('disc_number')) or 1
+        idx = by_pos.get((d, t)) if t is not None else None
+        if idx is not None and idx not in used:
+            used.add(idx)
+            pairs.append((lt, source_tracks[idx]))
+            continue
+        # Title-similarity fallback over still-unused source tracks.
+        lt_norm = _norm_title(lt.get('title'))
+        best_idx, best_score = None, 0.0
+        if lt_norm:
+            for i, st in enumerate(source_tracks):
+                if i in used:
+                    continue
+                score = SequenceMatcher(None, lt_norm, _norm_title(_get(st, 'name', 'title', 'track_name'))).ratio()
+                if score > best_score:
+                    best_score, best_idx = score, i
+        if best_idx is not None and best_score >= title_threshold:
+            used.add(best_idx)
+            pairs.append((lt, source_tracks[best_idx]))
+        else:
+            pairs.append((lt, None))
+    return pairs
+
+
+def _target_for_track(source_track: Any, album_meta: Dict[str, Any]) -> Dict[str, Any]:
+    """Normalized target tag values from the source for one track."""
+    album_artist = _first_artist(album_meta)
+    track_artist = _first_artist(source_track) or album_artist
+    return {
+        'title': (_get(source_track, 'name', 'title', 'track_name') or '').strip(),
+        'artist': album_artist,                 # album-level artist
+        'track_artist': track_artist,           # per-track (may equal album artist)
+        'album': (_get(album_meta, 'name', 'title', 'album_name') or '').strip(),
+        'year': _year(album_meta),
+        'genre': _genres_list(album_meta),      # list
+        'track_number': _int_or_none(_get(source_track, 'track_number')),
+        'disc_number': _int_or_none(_get(source_track, 'disc_number', default=1)) or 1,
+        'track_count': _int_or_none(_get(album_meta, 'total_tracks', 'track_count')),
+    }
+
+
+def _current_value(current_tags: Dict[str, Any], field: str):
+    if field == 'artist':
+        # _read_tags stores album_artist + artist; prefer album_artist for the album-level compare.
+        return current_tags.get('album_artist') or current_tags.get('artist') or ''
+    if field == 'genre':
+        return current_tags.get('genre') or ''
+    return current_tags.get(field)
+
+
+def _display(value) -> str:
+    if isinstance(value, list):
+        return ', '.join(str(v) for v in value)
+    return '' if value is None else str(value)
+
+
+def _is_empty(value) -> bool:
+    if value is None:
+        return True
+    if isinstance(value, str):
+        return value.strip() == ''
+    if isinstance(value, list):
+        return len(value) == 0
+    return False
+
+
+def plan_track(current_tags: Dict[str, Any], source_track: Any, album_meta: Dict[str, Any],
+               mode: str = MODE_OVERWRITE) -> Dict[str, Any]:
+    """Diff one library track's current tags against the source target.
+
+    Returns ``{changes, db_data}`` where ``changes`` is ``{field: {old, new}}``
+    for display, and ``db_data`` is the (minimal) payload for
+    ``write_tags_to_file`` — it contains ONLY the fields that should be written
+    under ``mode``, so applying never touches unrelated/unchanged tags.
+    """
+    target = _target_for_track(source_track, album_meta)
+    changes: Dict[str, Dict[str, str]] = {}
+    db_data: Dict[str, Any] = {}
+
+    for field in MANAGED_FIELDS:
+        new_val = target.get(field)
+        if _is_empty(new_val):
+            continue  # source gave us nothing for this field — leave the file alone
+        old_val = _current_value(current_tags, field)
+
+        if mode == MODE_FILL_MISSING and not _is_empty(old_val):
+            continue  # fill-missing only writes blanks
+
+        old_disp, new_disp = _display(old_val), _display(new_val)
+        if old_disp == new_disp:
+            continue  # already correct — nothing to write
+
+        changes[field] = {'old': old_disp, 'new': new_disp}
+        # Map managed field → write_tags_to_file db_data key.
+        if field == 'title':
+            db_data['title'] = new_val
+        elif field == 'artist':
+            db_data['artist_name'] = new_val           # = album artist for the writer
+            ta = target.get('track_artist')
+            if ta and ta != new_val:
+                db_data['track_artist'] = ta
+        elif field == 'album':
+            db_data['album_title'] = new_val
+        elif field == 'year':
+            db_data['year'] = new_val
+        elif field == 'genre':
+            db_data['genres'] = new_val                # list
+        elif field == 'track_number':
+            db_data['track_number'] = new_val
+        elif field == 'disc_number':
+            db_data['disc_number'] = new_val
+
+    # Always carry track_count alongside a track_number write (writers want both).
+    if 'track_number' in db_data and target.get('track_count'):
+        db_data['track_count'] = target['track_count']
+
+    return {'changes': changes, 'db_data': db_data}

core/maintenance/__init__.py

@@ -0,0 +1 @@
+"""Maintenance / one-off data-repair helpers."""

core/maintenance/dedupe_source_ids.py

@@ -0,0 +1,138 @@
+"""Find and clear corrupted source-id assignments on the ``artists`` table.
+
+Background
+----------
+The metadata enrichment workers (Deezer / AudioDB / Qobuz / Tidal) historically
+"corrected" an artist's source id from an album/track match **without a name
+check**. A track our library credits to one artist but which lives on another
+artist's curated/compilation album (e.g. anyone featured on Kendrick Lamar's
+"Black Panther" album) resolved to that album, whose primary artist is someone
+else — and the worker stamped that wrong id onto our artist. The upshot: one
+source id (Kendrick's Deezer ``525046``) ends up shared across several unrelated
+artists.
+
+That bug is now fixed in the workers (they name-check before correcting). This
+module is the one-off repair for libraries that already got corrupted.
+
+What counts as corruption
+-------------------------
+A *corrupt cluster* is one source id held by artists with **different names**.
+Legitimate duplicates — the SAME artist indexed on two media servers, sharing
+one id — have identical names and are left untouched.
+
+The repair
+----------
+For every corrupt cluster, clear the source id AND its match-status column on
+each member artist, so the (now name-checked) worker re-derives each artist's id
+correctly on the next enrichment pass. Only the ``artists`` table is touched;
+album/track rows keep their match status, so the album/track correction path
+isn't re-run during re-enrichment.
+
+``clear_corrupt_source_ids`` defaults to ``dry_run=True`` — it reports exactly
+what it would change and writes nothing unless explicitly told to apply.
+"""
+
+from __future__ import annotations
+
+import logging
+from typing import Any
+
+logger = logging.getLogger(__name__)
+
+# source -> (id column, match-status column) on the ``artists`` table.
+SOURCE_COLUMNS = {
+    'deezer': ('deezer_id', 'deezer_match_status'),
+    'spotify': ('spotify_artist_id', 'spotify_match_status'),
+    'itunes': ('itunes_artist_id', 'itunes_match_status'),
+    'musicbrainz': ('musicbrainz_id', 'musicbrainz_match_status'),
+    'discogs': ('discogs_id', 'discogs_match_status'),
+    'audiodb': ('audiodb_id', 'audiodb_match_status'),
+    'qobuz': ('qobuz_id', 'qobuz_match_status'),
+    'tidal': ('tidal_id', 'tidal_match_status'),
+}
+
+
+def _norm(name: str) -> str:
+    """Loose name key — lowercased, whitespace-collapsed."""
+    return ' '.join((name or '').lower().split())
+
+
+def _artists_columns(conn) -> set:
+    return {r[1] for r in conn.execute("PRAGMA table_info(artists)")}
+
+
+def find_corrupt_clusters(database: Any) -> list[dict]:
+    """Return corrupt source-id clusters across every known source column.
+
+    Each cluster is a dict: ``{source, id_column, status_column, source_id,
+    members: [(artist_id, name), ...]}``. A cluster is corrupt when one id is
+    held by artists with more than one distinct (normalized) name.
+    """
+    clusters: list[dict] = []
+    with database._get_connection() as conn:
+        existing = _artists_columns(conn)
+        for source, (id_col, status_col) in SOURCE_COLUMNS.items():
+            if id_col not in existing:
+                continue
+            rows = conn.execute(
+                f"SELECT {id_col}, id, name FROM artists "
+                f"WHERE {id_col} IS NOT NULL AND {id_col} != ''"
+            ).fetchall()
+            by_id: dict = {}
+            for sid, aid, name in rows:
+                by_id.setdefault(str(sid), []).append((aid, name))
+            for sid, members in by_id.items():
+                if len(members) > 1 and len({_norm(n) for _, n in members}) > 1:
+                    clusters.append({
+                        'source': source,
+                        'id_column': id_col,
+                        'status_column': status_col,
+                        'source_id': sid,
+                        'members': members,
+                    })
+    return clusters
+
+
+def clear_corrupt_source_ids(database: Any, dry_run: bool = True) -> dict:
+    """Clear source id + match status on every artist in a corrupt cluster.
+
+    ``dry_run=True`` (default) writes nothing — the returned report shows
+    exactly what would change so the operator can review first. Pass
+    ``dry_run=False`` to apply.
+    """
+    clusters = find_corrupt_clusters(database)
+    report = {
+        'dry_run': dry_run,
+        'cluster_count': len(clusters),
+        'artist_count': sum(len(c['members']) for c in clusters),
+        'by_source': {},
+        'clusters': [],
+    }
+    for c in clusters:
+        report['by_source'][c['source']] = (
+            report['by_source'].get(c['source'], 0) + len(c['members'])
+        )
+        report['clusters'].append({
+            'source': c['source'],
+            'source_id': c['source_id'],
+            'artists': sorted(n for _, n in c['members']),
+        })
+
+    if not dry_run and clusters:
+        with database._get_connection() as conn:
+            for c in clusters:
+                ids = [aid for aid, _ in c['members']]
+                placeholders = ','.join('?' for _ in ids)
+                conn.execute(
+                    f"UPDATE artists SET {c['id_column']} = NULL, "
+                    f"{c['status_column']} = NULL WHERE id IN ({placeholders})",
+                    ids,
+                )
+            conn.commit()
+        logger.info(
+            f"Cleared {report['artist_count']} corrupt source ids across "
+            f"{report['cluster_count']} clusters — re-run enrichment to "
+            f"re-derive them correctly"
+        )
+
+    return report

core/matching/script_compat.py

@@ -0,0 +1,96 @@
+"""Writing-system (script) compatibility helpers for metadata comparison.
+
+Issue #797 — AcoustID returns a recording's title/artist in their
+*original* script (e.g. ``久石譲`` for Joe Hisaishi) while SoulSync's
+expected metadata is romanized / English (``Joe Hisaishi``). A raw
+string-similarity comparison between two different writing systems
+scores ~0 even when they name the very same artist, so correct
+downloads of non-English artists get false-quarantined.
+
+These pure helpers let callers DETECT that situation — "one side is
+written in a non-Latin script, the other in Latin" — so the comparison
+logic can stop treating an untranslatable title/artist as evidence the
+file is wrong.
+
+Deliberately conservative: a single accented Latin character (``é``,
+``ñ``, ``ü``) is still Latin, NOT a script mismatch. Only genuinely
+different writing systems (CJK, Hangul, Cyrillic, Greek, Arabic,
+Hebrew, Thai, …) count as "non-Latin".
+"""
+
+from __future__ import annotations
+
+# Unicode ranges for non-Latin writing systems we treat as a "hard"
+# script difference. Latin (incl. Latin-1 Supplement / Extended with
+# diacritics) is intentionally absent — accented Latin is still Latin.
+# CJK ranges mirror core.matching_engine's issue #722 detection so the
+# two stay consistent.
+_NONLATIN_RANGES = (
+    ('Ͱ', 'Ͽ'),  # Greek and Coptic
+    ('Ѐ', 'ӿ'),  # Cyrillic
+    ('Ԁ', 'ԯ'),  # Cyrillic Supplement
+    ('֐', '׿'),  # Hebrew
+    ('؀', 'ۿ'),  # Arabic
+    ('ݐ', 'ݿ'),  # Arabic Supplement
+    ('฀', '๿'),  # Thai
+    ('⺀', '⻿'),  # CJK Radicals Supplement
+    ('぀', 'ゟ'),  # Hiragana
+    ('゠', 'ヿ'),  # Katakana
+    ('㐀', '䶿'),  # CJK Unified Ideographs Extension A
+    ('一', '鿿'),  # CJK Unified Ideographs
+    ('가', '힯'),  # Hangul Syllables
+    ('豈', '﫿'),  # CJK Compatibility Ideographs
+    ('ｦ', 'ￜ'),  # Halfwidth Katakana / Hangul
+)
+
+
+def _is_nonlatin_char(c: str) -> bool:
+    """True when ``c`` belongs to a non-Latin writing system."""
+    for lo, hi in _NONLATIN_RANGES:
+        if lo <= c <= hi:
+            return True
+    return False
+
+
+def has_strong_nonlatin(text: str) -> bool:
+    """True when ``text`` contains at least one non-Latin-script letter.
+
+    Accented Latin (``Beyoncé``, ``Sigur Rós``, ``Mötley Crüe``) returns
+    False — those are Latin. ``久石譲``, ``Дмитрий``, ``방탄소년단`` return True.
+    """
+    if not text:
+        return False
+    return any(_is_nonlatin_char(c) for c in text)
+
+
+def _has_latin_letter(text: str) -> bool:
+    """True when ``text`` contains an ASCII A–Z / a–z letter."""
+    if not text:
+        return False
+    return any(('a' <= c <= 'z') or ('A' <= c <= 'Z') for c in text)
+
+
+def is_cross_script_mismatch(a: str, b: str) -> bool:
+    """True when ``a`` and ``b`` are written in different scripts.
+
+    Specifically: exactly one side uses a non-Latin writing system while
+    the other is genuine Latin text. This is the signal that a raw
+    similarity score between the two is meaningless (a romanized name vs
+    its native-script form), NOT that they name different things.
+
+    Symmetric. Returns False when:
+      - both sides are Latin (ordinary English-vs-English comparison),
+      - both sides are non-Latin (same-script comparison still works),
+      - either side is empty / has no comparable letters.
+    """
+    a_nonlatin = has_strong_nonlatin(a)
+    b_nonlatin = has_strong_nonlatin(b)
+    if a_nonlatin == b_nonlatin:
+        # Same script class on both sides (or neither has non-Latin) —
+        # similarity comparison is meaningful, no script bridge needed.
+        return False
+    # Exactly one side is non-Latin. It's only a true cross-script case
+    # if the OTHER side is real Latin text (not punctuation / digits).
+    if a_nonlatin:
+        return _has_latin_letter(b)
+    return _has_latin_letter(a)

core/metadata/canonical_version.py

@@ -207,4 +207,24 @@ def pick_canonical_release(
     return best, best_score
 
 
-__all__ = ["score_release_against_files", "pick_canonical_release"]
+# Album sources the canonical system reads (mirror of
+# core.library_reorganize._ALBUM_ID_COLUMNS — a test pins them in sync). A manual
+# match on any of these should pin/lock the canonical version (#758); a match on
+# a source the canonical tools don't read (e.g. lastfm) has no version to pin.
+CANONICAL_ALBUM_SOURCES = frozenset({'spotify', 'itunes', 'deezer', 'discogs', 'hydrabase'})
+
+
+def should_pin_manual_canonical(entity_type: str, source: str) -> bool:
+    """Whether a manual match should also pin (and lock) the canonical album
+    version (#758). True only for an ALBUM match on a canonical-recognised
+    source — so the user's chosen edition becomes the authority every downstream
+    tool (track-number repair, reorganize, missing-tracks) reads, and the auto
+    resolve job won't override it.
+    """
+    return entity_type == 'album' and source in CANONICAL_ALBUM_SOURCES
+
+
+__all__ = [
+    "score_release_against_files", "pick_canonical_release",
+    "CANONICAL_ALBUM_SOURCES", "should_pin_manual_canonical",
+]

core/metadata/source.py

@@ -1122,6 +1122,60 @@ def extract_source_metadata(context: dict, artist: dict, album_info: dict) -> di
     return metadata
 
 
+def embed_known_source_ids(audio_file, metadata: dict) -> list:
+    """Embed ALREADY-KNOWN source IDs into a file's tags, no API re-fetch.
+
+    For the library re-tag / "Write Tags" paths: ``metadata`` carries flat id
+    keys already stored in the DB (``spotify_track_id``, ``spotify_album_id``,
+    ``itunes_track_id``, ``itunes_album_id``, ``musicbrainz_recording_id``,
+    ``musicbrainz_release_id``, …). Reuses the SAME canonical, format-specific,
+    Picard-compatible frame writer as the import post-process
+    (``_write_embedded_metadata``) so the frames never diverge — it just skips
+    the heavy multi-source re-search that ``embed_source_ids`` does.
+
+    The caller is responsible for saving the file. Returns the canonical tag
+    names written (for logging/diagnostics).
+    """
+    cfg = get_config_manager()
+    symbols = get_mutagen_symbols()
+    if not symbols or audio_file is None:
+        return []
+    try:
+        id_tags = _collect_source_ids(metadata, cfg)
+        # MusicBrainz ids aren't in _collect_source_ids (they come from the MB
+        # processor at import time); add them from the DB when present, using
+        # the canonical names the frame map already knows.
+        if cfg.get("musicbrainz.embed_tags", True) is not False:
+            if metadata.get("musicbrainz_recording_id"):
+                id_tags["MUSICBRAINZ_RECORDING_ID"] = metadata["musicbrainz_recording_id"]
+            if metadata.get("musicbrainz_release_id"):
+                id_tags["MUSICBRAINZ_RELEASE_ID"] = metadata["musicbrainz_release_id"]
+        if not id_tags:
+            return []
+        pp = _blank_post_process_state()
+        pp["id_tags"] = id_tags
+        _write_embedded_metadata(audio_file, metadata, pp, cfg, symbols)
+        return list(id_tags.keys())
+    except Exception as exc:
+        logger.debug("embed_known_source_ids failed: %s", exc)
+        return []
+
+
+def _blank_post_process_state() -> dict:
+    """A fully-defaulted post-process state so _write_embedded_metadata can run
+    with only id_tags set (every enrichment branch no-ops on the blanks)."""
+    return {
+        "id_tags": {}, "track_title": "", "artist_name": "", "batch_artist_name": None,
+        "metadata": {}, "recording_mbid": None, "artist_mbid": None, "release_mbid": "",
+        "mb_genres": [], "isrc": None, "deezer_bpm": None, "deezer_isrc": None,
+        "tidal_bpm": None, "hifi_bpm": None, "hifi_copyright": None, "audiodb_mood": None,
+        "audiodb_style": None, "audiodb_genre": None, "tidal_isrc": None,
+        "tidal_copyright": None, "hifi_isrc": None, "qobuz_isrc": None,
+        "qobuz_copyright": None, "qobuz_label": None, "lastfm_tags": [],
+        "lastfm_url": None, "genius_url": None, "release_year": None,
+    }
+
+
 def embed_source_ids(audio_file, metadata: dict, context: dict = None, runtime=None):
     cfg = get_config_manager()
     symbols = get_mutagen_symbols()

core/musicbrainz_worker.py

@@ -5,7 +5,7 @@ from datetime import datetime, timedelta
 from utils.logging_config import get_logger
 from database.music_database import MusicDatabase
 from core.musicbrainz_service import MusicBrainzService
-from core.worker_utils import interruptible_sleep
+from core.worker_utils import interruptible_sleep, source_id_conflict
 
 logger = get_logger("musicbrainz_worker")
 
@@ -367,8 +367,17 @@ class MusicBrainzWorker:
 
             if item_type == 'artist':
                 result = self.mb_service.match_artist(item_name)
-                if result and result.get('mbid'):
-                    self.mb_service.update_artist_mbid(item_id, result['mbid'], 'matched')
+                mbid = result.get('mbid') if result else None
+                # MB's combined score can match a weak name ("Grant" -> "Amy
+                # Grant") when its own relevance rank is high. Guard against
+                # assigning an mbid a differently-named artist already holds, so
+                # one mbid can't be smeared across unrelated artists.
+                conflict = (
+                    source_id_conflict(self.db, 'musicbrainz_id', mbid, item_id, item_name)
+                    if mbid else None
+                )
+                if mbid and not conflict:
+                    self.mb_service.update_artist_mbid(item_id, mbid, 'matched')
                     # Issue #442 — pull alternate-spelling aliases (Japanese
                     # kanji, Cyrillic, etc.) so the verifier can recognise
                     # cross-script artist names without re-querying MB on
@@ -377,7 +386,7 @@ class MusicBrainzWorker:
                     # empty list) so a transient MB outage never regresses
                     # the enrichment outcome.
                     try:
-                        aliases = self.mb_service.fetch_artist_aliases(result['mbid'])
+                        aliases = self.mb_service.fetch_artist_aliases(mbid)
                         if aliases:
                             self.mb_service.update_artist_aliases(item_id, aliases)
                             logger.debug(
@@ -388,11 +397,17 @@ class MusicBrainzWorker:
                             "Alias enrichment failed for artist '%s': %s", item_name, alias_err,
                         )
                     self.stats['matched'] += 1
-                    logger.info(f"Matched artist '{item_name}' → MBID: {result['mbid']}")
+                    logger.info(f"Matched artist '{item_name}' → MBID: {mbid}")
                 else:
                     self.mb_service.update_artist_mbid(item_id, None, 'not_found')
                     self.stats['not_found'] += 1
-                    logger.debug(f"No match for artist '{item_name}'")
+                    if conflict:
+                        logger.debug(
+                            f"Artist '{item_name}' → MBID {mbid} skipped: "
+                            f"already claimed by '{conflict}'"
+                        )
+                    else:
+                        logger.debug(f"No match for artist '{item_name}'")
 
             elif item_type == 'album':
                 artist_name = item.get('artist')

core/navidrome_client.py

@@ -192,6 +192,14 @@ class NavidromeClient(MediaServerClient):
         """Get available music folders from Navidrome."""
         if not self.ensure_connection():
             return []
+        return self._fetch_music_folders()
+
+    def _fetch_music_folders(self) -> list:
+        """Fetch + parse the Navidrome music folders. Assumes the connection is
+        already established (base_url/username set) and does NOT call
+        ensure_connection — so it is safe to call from inside _setup_client's
+        restore step without re-entering the connection guard (which would
+        otherwise bail with _is_connecting=True and return an empty list)."""
         try:
             response = self._make_request('getMusicFolders')
             if not response:
@@ -216,7 +224,10 @@ class NavidromeClient(MediaServerClient):
                     logger.info(f"Set music folder to: {folder_name} (ID: {self.music_folder_id})")
                     from database.music_database import MusicDatabase
                     db = MusicDatabase()
+                    # Persist the id (stable across renames) as the primary key,
+                    # keep the name for display + back-compat fallback.
                     db.set_preference('navidrome_music_folder', folder_name)
+                    db.set_preference('navidrome_music_folder_id', folder['key'])
                     return True
             # If folder_name is empty, clear the selection
             if not folder_name:
@@ -225,6 +236,7 @@ class NavidromeClient(MediaServerClient):
                 from database.music_database import MusicDatabase
                 db = MusicDatabase()
                 db.set_preference('navidrome_music_folder', '')
+                db.set_preference('navidrome_music_folder_id', '')
                 logger.info("Cleared music folder selection — will use all libraries")
                 return True
             logger.warning(f"Music folder '{folder_name}' not found")
@@ -276,14 +288,35 @@ class NavidromeClient(MediaServerClient):
                 try:
                     from database.music_database import MusicDatabase
                     db = MusicDatabase()
+                    saved_id = db.get_preference('navidrome_music_folder_id')
                     saved_folder = db.get_preference('navidrome_music_folder')
-                    if saved_folder:
-                        folders = self.get_music_folders()
-                        for folder in folders:
-                            if folder['title'] == saved_folder:
-                                self.music_folder_id = folder['key']
-                                logger.info(f"Restored music folder preference: {saved_folder} (ID: {self.music_folder_id})")
-                                break
+                    if saved_id or saved_folder:
+                        # Use the non-reentrant fetch: we're still inside
+                        # ensure_connection() here (_is_connecting=True), so the
+                        # public get_music_folders() would re-enter the guard and
+                        # return [], silently dropping the saved selection.
+                        folders = self._fetch_music_folders()
+                        # Match by id first (stable across renames in Navidrome);
+                        # fall back to name for installs saved before the id was
+                        # persisted.
+                        matched = None
+                        if saved_id:
+                            matched = next((f for f in folders if f['key'] == str(saved_id)), None)
+                        if matched is None and saved_folder:
+                            matched = next((f for f in folders if f['title'] == saved_folder), None)
+                        if matched is not None:
+                            self.music_folder_id = matched['key']
+                            logger.info(f"Restored music folder preference: {matched['title']} (ID: {self.music_folder_id})")
+                            # Self-heal drifted prefs: a pre-id install (no saved
+                            # id) or a folder renamed in Navidrome (stale name).
+                            # id stays the durable key; name is kept fresh so the
+                            # settings dropdown highlights the right option.
+                            if str(saved_id or '') != matched['key'] or (saved_folder or '') != matched['title']:
+                                try:
+                                    db.set_preference('navidrome_music_folder_id', matched['key'])
+                                    db.set_preference('navidrome_music_folder', matched['title'])
+                                except Exception as heal_err:
+                                    logger.debug(f"Could not self-heal music folder prefs: {heal_err}")
                 except Exception as e:
                     logger.warning(f"Could not restore music folder preference: {e}")
             else:
@@ -1091,6 +1124,60 @@ class NavidromeClient(MediaServerClient):
             logger.error(f"Error appending to Navidrome playlist '{playlist_name}': {e}")
             return False
 
+    def reconcile_playlist(self, playlist_name: str, tracks) -> bool:
+        """In-place reconcile (#792): add missing + remove gone via Subsonic
+        updatePlaylist (songIdToAdd / songIndexToRemove), keeping the existing
+        playlist object so its comment/identity survive — no delete/recreate.
+        Creates the playlist if missing. Returns False so the caller can fall
+        back to replace on any failure."""
+        if not self.ensure_connection():
+            return False
+        try:
+            from core.sync.playlist_edit import plan_playlist_reconcile
+            existing_playlists = self.get_playlists_by_name(playlist_name)
+            if not existing_playlists:
+                logger.info(f"Navidrome reconcile: '{playlist_name}' doesn't exist — creating")
+                return self.create_playlist(playlist_name, tracks)
+
+            primary = existing_playlists[0]
+            existing_tracks = self.get_playlist_tracks(primary.id)
+            current_ids = [str(t.id) for t in existing_tracks if getattr(t, 'id', None)]
+            desired_ids = []
+            for t in tracks:
+                tid = (str(t.ratingKey) if hasattr(t, 'ratingKey')
+                       else str(t.id) if getattr(t, 'id', None)
+                       else str(t.get('id', '')) if isinstance(t, dict) else '')
+                if tid:
+                    desired_ids.append(tid)
+
+            plan = plan_playlist_reconcile(current_ids, desired_ids)
+            if not plan['add'] and not plan['remove']:
+                return True
+
+            params = {'playlistId': primary.id}
+            if plan['add']:
+                params['songIdToAdd'] = plan['add']
+            if plan['remove']:
+                # Indices into the CURRENT list; remove descending so earlier
+                # removals don't shift the indices of later ones.
+                remove_set = set(plan['remove'])
+                params['songIndexToRemove'] = sorted(
+                    (i for i, cid in enumerate(current_ids) if cid in remove_set),
+                    reverse=True,
+                )
+            response = self._make_request('updatePlaylist', params)
+            if response and response.get('status') == 'ok':
+                logger.info(
+                    f"Navidrome reconcile '{playlist_name}': +{len(plan['add'])} / "
+                    f"-{len(plan['remove'])} (playlist preserved)"
+                )
+                return True
+            logger.error(f"Navidrome reconcile failed for '{playlist_name}'")
+            return False
+        except Exception as e:
+            logger.error(f"Error reconciling Navidrome playlist '{playlist_name}': {e}")
+            return False
+
     def update_playlist(self, playlist_name: str, tracks) -> bool:
         """Update an existing playlist or create it if it doesn't exist. Handles duplicates."""
         if not self.ensure_connection():

core/plex_client.py

@@ -667,6 +667,53 @@ class PlexClient(MediaServerClient):
             logger.error(f"Error appending to Plex playlist '{playlist_name}': {e}")
             return False
 
+    def reconcile_playlist(self, playlist_name: str, tracks: List[TrackInfo]) -> bool:
+        """In-place reconcile (#792): bring an existing playlist's tracks to match
+        ``tracks`` by adding the missing ones and removing the gone ones, WITHOUT
+        deleting/recreating the playlist — so its custom poster, summary, and
+        ratingKey survive the sync. Creates the playlist if it doesn't exist.
+
+        Returns False on any failure so the caller can fall back to replace."""
+        if not self.ensure_connection():
+            return False
+        try:
+            from core.sync.playlist_edit import plan_playlist_reconcile
+            try:
+                existing = self.server.playlist(playlist_name)
+            except NotFound:
+                logger.info(f"Plex reconcile: '{playlist_name}' doesn't exist — creating")
+                return self.create_playlist(playlist_name, tracks)
+
+            current_items = [i for i in existing.items() if hasattr(i, 'ratingKey')]
+            current_ids = [str(i.ratingKey) for i in current_items]
+            desired_ids = [str(t.ratingKey) for t in tracks if hasattr(t, 'ratingKey')]
+            plan = plan_playlist_reconcile(current_ids, desired_ids)
+
+            add_set, remove_set = set(plan['add']), set(plan['remove'])
+            to_add = [t for t in tracks if hasattr(t, 'ratingKey') and str(t.ratingKey) in add_set]
+            to_remove = [i for i in current_items if str(i.ratingKey) in remove_set]
+
+            if to_add:
+                existing.addItems(to_add)
+            if to_remove:
+                try:
+                    existing.removeItems(to_remove)
+                except (AttributeError, TypeError):
+                    # Older plexapi: no batch removeItems — drop one at a time.
+                    for it in to_remove:
+                        try:
+                            existing.removeItem(it)
+                        except Exception as one_err:
+                            logger.debug("Plex reconcile: removeItem failed: %s", one_err)
+            logger.info(
+                f"Plex reconcile '{playlist_name}': +{len(to_add)} / -{len(to_remove)} "
+                f"(playlist preserved)"
+            )
+            return True
+        except Exception as e:
+            logger.error(f"Error reconciling Plex playlist '{playlist_name}': {e}")
+            return False
+
     def update_playlist(self, playlist_name: str, tracks: List[TrackInfo]) -> bool:
         if not self.ensure_connection():
             return False

core/qobuz_worker.py

@@ -8,7 +8,7 @@ from datetime import datetime, timedelta
 from utils.logging_config import get_logger
 from database.music_database import MusicDatabase
 from core.qobuz_client import _qobuz_is_rate_limited
-from core.worker_utils import interruptible_sleep
+from core.worker_utils import accept_artist_match, interruptible_sleep
 from core.enrichment.manual_match_honoring import honor_stored_match
 
 logger = get_logger("qobuz_worker")
@@ -301,13 +301,29 @@ class QobuzWorker:
         logger.debug(f"Name similarity: '{query_name}' vs '{result_name}' = {similarity:.2f}")
         return similarity >= self.name_similarity_threshold
 
-    def _verify_artist_id(self, item: Dict[str, Any], result_artist_id) -> bool:
-        """Verify/correct parent artist's Qobuz ID based on album/track match"""
+    def _verify_artist_id(self, item: Dict[str, Any], result_artist_id,
+                          result_artist_name: Optional[str] = None) -> bool:
+        """Verify/correct parent artist's Qobuz ID based on album/track match.
+
+        Only corrects when the result's artist *name* matches our parent artist —
+        otherwise a collaboration/compilation would stamp the wrong Qobuz id onto
+        our artist. See the Deezer fix for the full write-up."""
         parent_qobuz_id = item.get('artist_qobuz_id')
         if not parent_qobuz_id or not result_artist_id:
             return True
 
         if str(result_artist_id) != str(parent_qobuz_id):
+            parent_name = item.get('artist') or ''
+            if (result_artist_name and parent_name
+                    and not self._name_matches(parent_name, result_artist_name)):
+                logger.info(
+                    f"Skipping artist-ID correction from {item['type']} "
+                    f"'{item['name']}': result artist '{result_artist_name}' "
+                    f"≠ parent '{parent_name}' (collab/compilation, not a "
+                    f"correction)"
+                )
+                return True
+
             logger.info(
                 f"Artist ID correction from {item['type']} '{item['name']}': "
                 f"updating parent artist Qobuz ID from {parent_qobuz_id} to {result_artist_id}"
@@ -407,14 +423,19 @@ class QobuzWorker:
 
         if result:
             result_name = result.get('name', '')
-            if self._name_matches(artist_name, result_name):
-                qobuz_artist_id = result.get('id')
-                if not qobuz_artist_id:
-                    self._mark_status('artist', artist_id, 'error')
-                    self.stats['errors'] += 1
-                    logger.warning(f"Qobuz search result for '{artist_name}' has no ID")
-                    return
-
+            qobuz_artist_id = result.get('id')
+            ok, reason = accept_artist_match(
+                self.db, 'qobuz_id', qobuz_artist_id, artist_id, artist_name, result_name,
+            )
+            if not ok:
+                self._mark_status('artist', artist_id, 'not_found')
+                self.stats['not_found'] += 1
+                logger.debug(f"Artist '{artist_name}' not matched: {reason}")
+            elif not qobuz_artist_id:
+                self._mark_status('artist', artist_id, 'error')
+                self.stats['errors'] += 1
+                logger.warning(f"Qobuz search result for '{artist_name}' has no ID")
+            else:
                 # Fetch full artist details
                 full_artist = None
                 try:
@@ -425,10 +446,6 @@ class QobuzWorker:
                 self._update_artist(artist_id, result, full_artist)
                 self.stats['matched'] += 1
                 logger.info(f"Matched artist '{artist_name}' -> Qobuz ID: {qobuz_artist_id}")
-            else:
-                self._mark_status('artist', artist_id, 'not_found')
-                self.stats['not_found'] += 1
-                logger.debug(f"Name mismatch for artist '{artist_name}' (got '{result_name}')")
         else:
             if _qobuz_is_rate_limited():
                 logger.warning(f"Rate limited while searching artist '{artist_name}', will retry")
@@ -467,7 +484,8 @@ class QobuzWorker:
                 # Verify artist ID
                 result_artist = result.get('artist', {})
                 result_artist_id = result_artist.get('id') if result_artist else None
-                self._verify_artist_id(item, result_artist_id)
+                result_artist_name = result_artist.get('name') if result_artist else None
+                self._verify_artist_id(item, result_artist_id, result_artist_name)
 
                 # Fetch full album details
                 qobuz_album_id = result.get('id')
@@ -528,7 +546,8 @@ class QobuzWorker:
                 # Verify artist ID
                 result_artist = result.get('artist', result.get('performer', {}))
                 result_artist_id = result_artist.get('id') if result_artist else None
-                self._verify_artist_id(item, result_artist_id)
+                result_artist_name = result_artist.get('name') if result_artist else None
+                self._verify_artist_id(item, result_artist_id, result_artist_name)
 
                 # Fetch full track details
                 qobuz_track_id = result.get('id')

core/repair_jobs/__init__.py

@@ -45,6 +45,7 @@ _JOB_MODULES = [
     'core.repair_jobs.unknown_artist_fixer',
     'core.repair_jobs.discography_backfill',
     'core.repair_jobs.canonical_version_resolve',
+    'core.repair_jobs.library_retag',
 ]
 
 

core/repair_jobs/library_retag.py

@@ -0,0 +1,477 @@
+"""Library Re-tag Job — rewrite audio tags from a fresh metadata-source pull.
+
+Re-does ONLY the tagging part of post-processing (tags + cover art), IN PLACE:
+no file moves, no renames, no re-matching, no library reorganization. Only
+albums that are matched to a metadata source are eligible — the album's stored
+source id is used to pull fresh data to write.
+
+Dry-run by design: scan creates detailed, per-track findings (old -> new for
+every field that would change); nothing touches a file until you apply a
+finding. The apply handler lives in repair_worker (_fix_library_retag).
+"""
+
+import os
+
+from core.library.retag_planner import (
+    MODE_FILL_MISSING,
+    MODE_OVERWRITE,
+    match_source_tracks,
+    plan_track,
+)
+from core.metadata.album_tracks import get_album_for_source, get_album_tracks_for_source
+from core.metadata_service import get_primary_source, get_source_priority
+from core.repair_jobs import register_job
+from core.repair_jobs.base import JobContext, JobResult, RepairJob
+from utils.logging_config import get_logger
+
+logger = get_logger("repair_job.library_retag")
+
+# (source, albums-table column) in resolution-preference order is decided at
+# runtime from the configured source priority; this maps source -> column.
+_ALBUM_SOURCE_COLUMNS = {
+    'spotify': 'spotify_album_id',
+    'itunes': 'itunes_album_id',
+    'deezer': 'deezer_id',
+    'musicbrainz': 'musicbrainz_release_id',
+}
+
+
+def _read_current_tags(file_path):
+    try:
+        from core.soulsync_client import _read_tags
+        return _read_tags(file_path) or {}
+    except Exception as exc:
+        logger.debug("read tags failed for %s: %s", file_path, exc)
+        return {}
+
+
+def _run_full_enrich(file_path, full_meta) -> bool:
+    """'full' depth: run the same multi-source enrichment a fresh download gets
+    (MusicBrainz/Deezer/AudioDB/Tidal/… via embed_source_ids), ADDITIVELY — it
+    adds rich frames without clearing existing tags. Slow + API-heavy per track.
+    """
+    if not full_meta:
+        return False
+    try:
+        from core.metadata.common import get_mutagen_symbols
+        from core.metadata.source import embed_source_ids
+        symbols = get_mutagen_symbols()
+        if not symbols:
+            return False
+        audio = symbols.File(file_path)
+        if audio is None:
+            return False
+        if getattr(audio, 'tags', None) is None and hasattr(audio, 'add_tags'):
+            audio.add_tags()
+        embed_source_ids(audio, full_meta, context=None, runtime=None)
+        audio.save()
+        return True
+    except Exception as e:
+        logger.warning("full enrich failed for %s: %s", file_path, e)
+        return False
+
+
+def apply_track_plans(track_plans, cover_action=None, cover_url=None, full=False) -> dict:
+    """Write each plan's tags in place (+ optionally embed/refresh cover art),
+    reusing tag_writer.write_tags_to_file. ``file_path`` on each plan must be a
+    real, reachable path (caller resolves Docker paths). Shared by the dry-run=
+    False auto-apply and the repair_worker fix handler. Never raises.
+    """
+    import os as _os
+    result = {'written': 0, 'failed': 0, 'skipped': 0, 'cover_written': False}
+    embed_cover = bool(cover_action and cover_url)
+    cover_data = None
+    if embed_cover:
+        try:
+            from core.tag_writer import download_cover_art
+            cover_data = download_cover_art(cover_url)
+        except Exception as e:
+            logger.debug("retag cover download failed: %s", e)
+    embed_cover = embed_cover and cover_data is not None
+
+    from core.tag_writer import write_tags_to_file
+    last_dir = None
+    for tp in track_plans or []:
+        fp = tp.get('file_path')
+        db_data = tp.get('db_data') or {}
+        if not fp or not _os.path.isfile(fp) or (not db_data and not embed_cover):
+            result['skipped'] += 1
+            continue
+        try:
+            res = write_tags_to_file(fp, db_data, embed_cover=embed_cover, cover_data=cover_data)
+            if res.get('success'):
+                result['written'] += 1
+                last_dir = _os.path.dirname(fp)
+                if full and tp.get('full_meta'):
+                    _run_full_enrich(fp, tp['full_meta'])
+            else:
+                result['failed'] += 1
+        except Exception as e:
+            logger.warning("retag write failed for %s: %s", fp, e)
+            result['failed'] += 1
+
+    if cover_action and cover_data and last_dir:
+        try:
+            cover_path = _os.path.join(last_dir, 'cover.jpg')
+            if cover_action == 'replace' or not _os.path.exists(cover_path):
+                with open(cover_path, 'wb') as fh:
+                    fh.write(cover_data[0])
+                result['cover_written'] = True
+        except Exception as e:
+            logger.debug("retag cover.jpg write failed: %s", e)
+    return result
+
+
+def _add_source_ids(db_data, source, album_source_id, source_track):
+    """Stamp the album/track source IDs onto the write payload so the canonical
+    writer embeds them too (Spotify / iTunes / MusicBrainz)."""
+    album_key = {'spotify': 'spotify_album_id', 'itunes': 'itunes_album_id',
+                 'musicbrainz': 'musicbrainz_release_id'}.get(source)
+    track_key = {'spotify': 'spotify_track_id', 'itunes': 'itunes_track_id',
+                 'musicbrainz': 'musicbrainz_recording_id'}.get(source)
+    if album_key and album_source_id:
+        db_data[album_key] = album_source_id
+    if track_key:
+        tid = None
+        for k in ('id', 'track_id', 'source_track_id'):
+            v = source_track.get(k) if isinstance(source_track, dict) else getattr(source_track, k, None)
+            if v:
+                tid = v
+                break
+        if tid:
+            db_data[track_key] = tid
+
+
+_FULL_META_ID_KEYS = (
+    'spotify_album_id', 'spotify_track_id',
+    'itunes_album_id', 'itunes_track_id',
+    'musicbrainz_release_id', 'musicbrainz_recording_id',
+    'deezer_id',
+)
+
+
+def _build_full_meta(db_data, src, album_title, artist_name, lib_title):
+    """Metadata dict for the 'full' depth enrichment cascade. Carries the matched
+    source's ids so embed_source_ids resolves the right entity instead of guessing
+    by name."""
+    src_title = None
+    for k in ('name', 'title', 'track_name'):
+        v = src.get(k) if isinstance(src, dict) else getattr(src, k, None)
+        if v:
+            src_title = v
+            break
+    meta = {
+        'title': src_title or lib_title,
+        'album': album_title,
+        'album_artist': artist_name,
+        'artist': artist_name,
+    }
+    meta.update({k: db_data[k] for k in _FULL_META_ID_KEYS if db_data.get(k)})
+    return meta
+
+
+def _track_list(result):
+    """Normalize a get_album_tracks result into a plain list of track items."""
+    if result is None:
+        return []
+    if isinstance(result, list):
+        return result
+    if isinstance(result, dict):
+        for key in ('tracks', 'items', 'data'):
+            v = result.get(key)
+            if isinstance(v, list):
+                return v
+    v = getattr(result, 'tracks', None)
+    return v if isinstance(v, list) else []
+
+
+@register_job
+class LibraryRetagJob(RepairJob):
+    job_id = 'library_retag'
+    display_name = 'Library Re-tag'
+    description = 'Rewrites tags + cover art from a fresh metadata-source pull, in place'
+    help_text = (
+        'Re-tags albums in your library using a fresh pull from the metadata source '
+        'they are matched to — writing the tags (and optionally cover art) directly '
+        'into the files. It only does the tagging step: files are NOT moved, renamed, '
+        're-matched, or reorganized.\n\n'
+        'Only albums matched to a metadata source (Spotify / iTunes / Deezer / '
+        'MusicBrainz album id) are eligible, since the source is where the fresh data '
+        'comes from. Each finding lists every tag that would change (old -> new) per '
+        'track so you can review before applying — nothing is written until you do.\n\n'
+        'Settings:\n'
+        '- Depth: "light" writes the core tags + the matched source\'s ids (fast, '
+        'additive). "full" also runs the same multi-source enrichment a fresh '
+        'download gets (MusicBrainz / Deezer / AudioDB / Tidal / etc. — BPM, ISRC, '
+        'lyrics, moods, …); much richer but slower and API-heavy on a big library.\n'
+        '- Dry run (default ON): only create findings to review; nothing is written. '
+        'Turn it off to auto-apply on scan.\n'
+        '- Mode: "overwrite" rewrites every field the source provides; "fill_missing" '
+        'only fills blank tags (keeps your existing values).\n'
+        '- Cover art: replace / fill-missing / skip. "replace" force-refreshes '
+        'art on every matched album (use this after changing your cover-art '
+        'sources to re-pull fresh covers). When you have configured cover-art '
+        'sources (Settings > metadata enhancement art order), the art is pulled '
+        'from those; otherwise it falls back to the matched source\'s album image.\n'
+        '- Source: which matched source to pull from (default: your source priority).'
+    )
+    icon = 'repair-icon-retag'
+    default_enabled = False
+    default_interval_hours = 168
+    default_settings = {
+        'dry_run': True,
+        'depth': 'light',
+        'mode': MODE_OVERWRITE,
+        'cover_art': 'replace',
+        'source': 'auto',
+    }
+    setting_options = {
+        'depth': ['light', 'full'],
+        'mode': [MODE_OVERWRITE, MODE_FILL_MISSING],
+        'cover_art': ['replace', 'fill_missing', 'skip'],
+        'source': ['auto', 'spotify', 'itunes', 'deezer', 'musicbrainz'],
+    }
+    auto_fix = True
+
+    def _get_settings(self, context: JobContext) -> dict:
+        merged = dict(self.default_settings)
+        if context.config_manager:
+            cfg = context.config_manager.get(f'repair.jobs.{self.job_id}.settings', {}) or {}
+            merged.update(cfg)
+        return merged
+
+    def _source_order(self, settings) -> list:
+        override = (settings.get('source') or '').strip()
+        if override in _ALBUM_SOURCE_COLUMNS:
+            return [override]
+        return [s for s in get_source_priority(get_primary_source()) if s in _ALBUM_SOURCE_COLUMNS]
+
+    def scan(self, context: JobContext) -> JobResult:
+        result = JobResult()
+        settings = self._get_settings(context)
+        mode = settings.get('mode', MODE_OVERWRITE)
+        cover_mode = settings.get('cover_art', 'replace')
+        dry_run = settings.get('dry_run', True)
+        depth = settings.get('depth', 'light')
+        source_order = self._source_order(settings)
+        if not source_order:
+            logger.warning("Library re-tag: no usable metadata sources configured")
+            return result
+
+        # Albums that carry at least one usable source id.
+        cols = ', '.join(f'al.{c}' for c in _ALBUM_SOURCE_COLUMNS.values())
+        try:
+            with context.db._get_connection() as conn:
+                cursor = conn.cursor()
+                cursor.execute(f"""
+                    SELECT al.id, al.title, ar.name, {cols}
+                    FROM albums al
+                    LEFT JOIN artists ar ON ar.id = al.artist_id
+                    WHERE al.title IS NOT NULL AND al.title != ''
+                """)
+                albums = cursor.fetchall()
+        except Exception as e:
+            logger.error("Library re-tag: album query failed: %s", e, exc_info=True)
+            result.errors += 1
+            return result
+
+        total = len(albums)
+        if context.update_progress:
+            context.update_progress(0, total)
+        if context.report_progress:
+            context.report_progress(phase=f'Checking {total} albums for tag drift...', total=total)
+
+        for i, row in enumerate(albums):
+            if context.check_stop():
+                return result
+            if i % 5 == 0 and context.wait_if_paused():
+                return result
+            result.scanned += 1
+            if context.update_progress and (i + 1) % 5 == 0:
+                context.update_progress(i + 1, total)
+
+            album_id, album_title, artist_name = row[0], row[1], row[2]
+            source_ids = {src: row[3 + idx] for idx, src in enumerate(_ALBUM_SOURCE_COLUMNS)}
+
+            source = next((s for s in source_order if source_ids.get(s)), None)
+            if not source:
+                continue  # not matched to a usable source — skip
+            album_source_id = str(source_ids[source])
+
+            try:
+                self._scan_album(context, result, album_id, album_title, artist_name,
+                                 source, album_source_id, mode, cover_mode, dry_run, depth)
+            except Exception as e:
+                logger.debug("Library re-tag: album %s failed: %s", album_id, e)
+                result.errors += 1
+
+        if context.update_progress:
+            context.update_progress(total, total)
+        logger.info("Library re-tag scan: %d albums checked, %d findings",
+                    result.scanned, result.findings_created)
+        return result
+
+    def _scan_album(self, context, result, album_id, album_title, artist_name,
+                    source, album_source_id, mode, cover_mode, dry_run=True, depth='light'):
+        # Local tracks for this album.
+        with context.db._get_connection() as conn:
+            cur = conn.cursor()
+            cur.execute("""
+                SELECT id, title, track_number, disc_number, file_path
+                FROM tracks
+                WHERE album_id = ? AND file_path IS NOT NULL AND file_path != ''
+                ORDER BY disc_number, track_number
+            """, (album_id,))
+            library_tracks = [
+                {'id': r[0], 'title': r[1], 'track_number': r[2],
+                 'disc_number': r[3], 'file_path': r[4]}
+                for r in cur.fetchall()
+            ]
+        if not library_tracks:
+            return
+
+        album_meta = get_album_for_source(source, album_source_id)
+        source_tracks = _track_list(get_album_tracks_for_source(source, album_source_id))
+        if not album_meta or not source_tracks:
+            logger.debug("Library re-tag: no source data for album %s (%s)", album_id, source)
+            return
+
+        cover_url = None
+        for k in ('image_url', 'album_image_url', 'cover_url', 'thumb_url'):
+            v = album_meta.get(k) if isinstance(album_meta, dict) else getattr(album_meta, k, None)
+            if v:
+                cover_url = v
+                break
+
+        # Honor the user's configured cover-art sources (the same
+        # `metadata_enhancement.album_art_order` the post-process embed uses), so
+        # changing those sources and re-tagging pulls fresh art FROM them rather
+        # than always using the matched metadata source's album image. Non-
+        # breaking: select_preferred_art_url returns None when no order is
+        # configured, so we keep the source image. Skipped when not embedding art.
+        if cover_mode != 'skip':
+            try:
+                from core.metadata.art_lookup import select_preferred_art_url
+                order = (context.config_manager.get('metadata_enhancement.album_art_order')
+                         if context.config_manager else None)
+                preferred = select_preferred_art_url(artist_name, album_title, album_meta, order)
+                if preferred:
+                    cover_url = preferred
+            except Exception as e:
+                logger.debug("preferred cover-art lookup failed for album %s: %s", album_id, e)
+
+        # Cover action (album-level), independent of tag changes. Decided first
+        # so cover-only albums (tags fine, art missing) still include their
+        # tracks for the apply to embed art into.
+        cover_action = self._cover_action(cover_mode, cover_url, library_tracks)
+
+        pairs = match_source_tracks(source_tracks, library_tracks)
+        track_plans = []
+        unmatched = []
+        for lib, src in pairs:
+            if src is None:
+                unmatched.append(lib['title'] or os.path.basename(lib['file_path']))
+                continue
+            if not os.path.isfile(lib['file_path']):
+                continue  # not reachable at the stored path — skip (apply resolves paths)
+            current = _read_current_tags(lib['file_path'])
+            plan = plan_track(current, src, album_meta, mode=mode)
+            # Include a track when its tags change, OR when there's a cover action
+            # to apply to it (db_data may be empty — apply embeds art either way).
+            if plan['changes'] or cover_action:
+                db_data = plan['db_data']
+                _add_source_ids(db_data, source, album_source_id, src)
+                tp = {
+                    'file_path': lib['file_path'],
+                    'track_id': lib['id'],
+                    'title': lib['title'],
+                    'changes': plan['changes'],
+                    'db_data': db_data,
+                }
+                if depth == 'full':
+                    tp['full_meta'] = _build_full_meta(
+                        db_data, src, album_title, artist_name, lib['title'])
+                track_plans.append(tp)
+
+        tag_change_tracks = sum(1 for tp in track_plans if tp['changes'])
+        if not tag_change_tracks and not cover_action:
+            result.skipped += 1
+            return
+
+        # Not dry-run: apply the tags in place now (the track paths were already
+        # isfile-checked above) and count it as an auto-fix — no finding.
+        if not dry_run:
+            res = apply_track_plans(track_plans, cover_action, cover_url, full=(depth == 'full'))
+            if res['written'] or res['cover_written']:
+                result.auto_fixed += 1
+            else:
+                result.errors += 1
+            return
+
+        total_changes = sum(len(tp['changes']) for tp in track_plans)
+        summary_bits = []
+        if tag_change_tracks:
+            summary_bits.append(f"{tag_change_tracks} track(s), {total_changes} tag change(s)")
+        if cover_action:
+            summary_bits.append(f"cover art ({cover_action})")
+        if depth == 'full':
+            summary_bits.append("full multi-source enrichment")
+        desc = (f'Album "{album_title}" by {artist_name or "Unknown"} would be re-tagged from '
+                f'{source} ({", ".join(summary_bits)}).')
+        if unmatched:
+            desc += f' {len(unmatched)} track(s) could not be matched to the source and are left untouched.'
+
+        if context.create_finding:
+            inserted = context.create_finding(
+                job_id=self.job_id,
+                finding_type='library_retag',
+                severity='info',
+                entity_type='album',
+                entity_id=str(album_id),
+                file_path=None,
+                title=f'Re-tag: {album_title or "Unknown"} ({tag_change_tracks} track(s))',
+                description=desc,
+                details={
+                    'album_id': album_id,
+                    'album_title': album_title,
+                    'artist': artist_name,
+                    'source': source,
+                    'album_source_id': album_source_id,
+                    'depth': depth,
+                    'mode': mode,
+                    'cover_mode': cover_mode,
+                    'cover_url': cover_url,
+                    'cover_action': cover_action,
+                    'tracks': track_plans,        # each carries its db_data for a deterministic apply
+                    'unmatched': unmatched,
+                },
+            )
+            if inserted:
+                result.findings_created += 1
+            else:
+                result.findings_skipped_dedup += 1
+
+    @staticmethod
+    def _cover_action(cover_mode, cover_url, library_tracks):
+        """Return 'replace' / 'fill' / None for the album's cover under the mode."""
+        if cover_mode == 'skip' or not cover_url:
+            return None
+        if cover_mode == 'replace':
+            return 'replace'
+        # fill_missing — only if the album has no art on disk
+        try:
+            from core.metadata.art_apply import album_has_art_on_disk
+            rep = library_tracks[0]['file_path'] if library_tracks else ''
+            return None if album_has_art_on_disk(rep) else 'fill'
+        except Exception:
+            return None
+
+    def estimate_scope(self, context: JobContext) -> int:
+        try:
+            with context.db._get_connection() as conn:
+                cur = conn.cursor()
+                cur.execute("SELECT COUNT(*) FROM albums WHERE title IS NOT NULL AND title != ''")
+                row = cur.fetchone()
+                return row[0] if row else 0
+        except Exception:
+            return 0

core/repair_jobs/missing_cover_art.py

@@ -46,9 +46,10 @@ class MissingCoverArtJob(RepairJob):
     description = 'Finds albums missing artwork and locates art from metadata sources'
     help_text = (
         'Scans your library for albums that have no cover art stored in the database. '
-        'For each missing cover, it searches the configured metadata sources using the '
-        'album name and artist to find matching artwork. If Prefer Source is set, that '
-        'source is tried first; otherwise the primary metadata source is used.\n\n'
+        'For each missing cover, it searches for matching artwork using the album name '
+        'and artist. If you have configured cover-art sources (Settings > metadata '
+        'enhancement art order), those are used first; otherwise it falls back to '
+        'Prefer Source (if set) or the primary metadata source.\n\n'
         'When artwork is found, a finding is created with the image URL so you can review '
         'and apply it. The job does not download or embed artwork automatically.\n\n'
         'Settings:\n'
@@ -66,6 +67,10 @@ class MissingCoverArtJob(RepairJob):
         settings = self._get_settings(context)
         primary_source = get_primary_source()
         source_priority = get_source_priority(primary_source)
+        # User's configured cover-art source order (caa/deezer/itunes/spotify/
+        # audiodb). Empty by default → falls back to the source-priority loop.
+        art_order = (context.config_manager.get('metadata_enhancement.album_art_order')
+                     if context.config_manager else None)
         prefer_source = settings.get('prefer_source')
         if prefer_source and prefer_source != primary_source and prefer_source in source_priority:
             source_priority.remove(prefer_source)
@@ -170,11 +175,27 @@ class MissingCoverArtJob(RepairJob):
 
             artwork_url = None
 
+            # Honor the user's configured cover-art sources first (the same
+            # metadata_enhancement.album_art_order the post-process embed and the
+            # Library Re-tag job use) so "cover art sources" means one thing
+            # app-wide. Non-breaking: returns None when no order is configured
+            # (the default), so we fall back to the prefer_source / metadata
+            # source-priority loop below — unchanged behavior for existing users.
+            try:
+                from core.metadata.art_lookup import select_preferred_art_url
+                artwork_url = select_preferred_art_url(
+                    artist_name, title,
+                    {'musicbrainz_release_id': None}, art_order,
+                )
+            except Exception as e:
+                logger.debug("preferred cover-art lookup failed for album %s: %s", album_id, e)
+
             # Try source-specific IDs first, then title/artist search, in priority order.
-            for source in source_priority:
-                artwork_url = self._try_source(source, source_album_ids.get(source), title, artist_name)
-                if artwork_url:
-                    break
+            if not artwork_url:
+                for source in source_priority:
+                    artwork_url = self._try_source(source, source_album_ids.get(source), title, artist_name)
+                    if artwork_url:
+                        break
 
             if artwork_url:
                 if context.report_progress:

core/repair_worker.py

@@ -976,6 +976,7 @@ class RepairWorker:
             'unknown_artist': self._fix_unknown_artist,
             'acoustid_mismatch': self._fix_acoustid_mismatch,
             'missing_discography_track': self._fix_discography_backfill,
+            'library_retag': self._fix_library_retag,
         }
         handler = handlers.get(finding_type)
         if not handler:
@@ -1356,6 +1357,43 @@ class RepairWorker:
             msg = 'Updated database thumbnail, but could not write art to files (read-only?)'
         return {'success': True, 'action': 'applied_cover_art', 'message': msg, 'art_result': art_result}
 
+    def _fix_library_retag(self, entity_type, entity_id, file_path, details):
+        """Apply a library re-tag finding: write each track's planned tags in
+        place (core.tag_writer.write_tags_to_file) + optionally embed/refresh
+        cover art. Only ADDS/overwrites the planned fields — no moves/renames."""
+        tracks = details.get('tracks') or []
+        if not tracks:
+            return {'success': False, 'error': 'No tracks to re-tag in finding'}
+
+        # Resolve container/host path mismatches, then delegate to the shared
+        # apply path the job's auto-fix mode also uses.
+        download_folder = self._config_manager.get('soulseek.download_path', '') if self._config_manager else None
+        resolved_plans = []
+        for t in tracks:
+            raw = t.get('file_path')
+            if not raw:
+                continue
+            rp = _resolve_file_path(raw, self.transfer_folder, download_folder,
+                                    config_manager=self._config_manager) or raw
+            plan = {'file_path': rp, 'db_data': t.get('db_data') or {}}
+            if t.get('full_meta'):
+                plan['full_meta'] = t['full_meta']
+            resolved_plans.append(plan)
+
+        from core.repair_jobs.library_retag import apply_track_plans
+        res = apply_track_plans(resolved_plans, details.get('cover_action'), details.get('cover_url'),
+                                full=(details.get('depth') == 'full'))
+
+        if res['written'] == 0 and not res['cover_written']:
+            return {'success': False,
+                    'error': 'Nothing could be written — files unreachable or read-only?'}
+        msg = f"Re-tagged {res['written']} track(s)"
+        if res['failed']:
+            msg += f" ({res['failed']} failed)"
+        if res['cover_written']:
+            msg += ' + refreshed cover.jpg'
+        return {'success': True, 'action': 'library_retag', 'message': msg, **res}
+
     def _fix_metadata_gap(self, entity_type, entity_id, file_path, details):
         """Apply found metadata fields to the track."""
         found_fields = details.get('found_fields')

core/search/by_id.py

@@ -0,0 +1,371 @@
+"""Resolve a pasted metadata link to a single album/track/artist result.
+
+This backs the Search page's "Link / ID" mode (#775): instead of a fuzzy
+name search, the user pastes a provider URL (or a bare ID) and we look the
+entity up *directly* on the owning source — no scoring, no guessing.
+
+Design notes
+------------
+- **Links only.** A full URL carries its source in the domain
+  (``open.spotify.com`` → spotify, ``musicbrainz.org`` → musicbrainz, …)
+  and its kind in the path (``/album/`` vs ``/track/``), so it resolves to
+  exactly one unambiguous lookup. The ``spotify:album:ID`` URI is accepted
+  too since it's equally explicit. Bare IDs are intentionally rejected: a
+  bare number like ``525046`` carries no source and no entity type, so it
+  would resolve to whatever album/track happens to own that id on some
+  source — often an unrelated entity. Paste the link instead.
+
+- **Reuses existing per-source get-by-id.** Spotify/iTunes/MusicBrainz all
+  expose ``get_album``; Deezer exposes ``get_album_metadata``; all four
+  expose ``get_track_details``. Those already normalize to a common
+  "Spotify-shaped" dict, so a single adapter projects them onto the same
+  card shape the enhanced-search dropdown renders (see
+  ``core/search/sources.py``).
+
+- **Purely additive.** Nothing here mutates existing search behavior; the
+  route layer calls :func:`resolve_identifier` only for the new mode.
+
+The module is import-safe and side-effect free: clients are resolved through
+an injected ``client_resolver`` (defaulting to the orchestrator's
+``resolve_client``) so the seam is unit-testable with fakes.
+"""
+
+from __future__ import annotations
+
+import logging
+from typing import Any, Callable, NamedTuple, Optional
+from urllib.parse import parse_qs, urlparse
+
+logger = logging.getLogger(__name__)
+
+# Sources we can resolve a link/ID against. These are exactly the metadata
+# providers whose public links a user would paste AND whose get-by-id returns
+# the common Spotify-shaped dict. Streaming download backends (Tidal/Qobuz)
+# return raw API shapes and aren't metadata-link sources, so they're omitted.
+SUPPORTED_SOURCES = ('spotify', 'itunes', 'musicbrainz', 'deezer')
+
+# Domains we recognize — used to detect a pasted URL even when the user
+# omitted the scheme (e.g. "open.spotify.com/album/…").
+_KNOWN_HOSTS = (
+    'open.spotify.com', 'music.apple.com', 'itunes.apple.com',
+    'musicbrainz.org', 'deezer.com',
+)
+
+
+class LookupTarget(NamedTuple):
+    """One (source, kind, id) lookup to attempt.
+
+    ``kind`` is ``'album'`` or ``'track'`` — always pinned by the URL path or
+    URI type (links-only input). The ``Optional`` typing is kept defensively:
+    the resolver falls back to album-then-track if a future parser path ever
+    yields ``None``.
+    """
+
+    source: str
+    kind: Optional[str]
+    id: str
+
+
+# --------------------------------------------------------------------------
+# Parsing
+# --------------------------------------------------------------------------
+
+def _kind_from_keyword(keyword: str) -> Optional[str]:
+    """Map a URL/URI path keyword to a lookup kind."""
+    if keyword in ('album', 'release', 'release-group'):
+        return 'album'
+    if keyword in ('track', 'recording', 'song'):
+        return 'track'
+    if keyword == 'artist':
+        return 'artist'
+    return None
+
+
+def _parse_spotify_uri(raw: str) -> Optional[LookupTarget]:
+    """``spotify:album:ID`` / ``spotify:track:ID``."""
+    parts = raw.split(':')
+    if len(parts) >= 3 and parts[0] == 'spotify':
+        kind = _kind_from_keyword(parts[1])
+        if kind:
+            return LookupTarget('spotify', kind, parts[-1])
+    return None
+
+
+def _parse_url(raw: str) -> list[LookupTarget]:
+    """Parse a provider URL into lookup targets (empty if unrecognized)."""
+    parsed = urlparse(raw)
+    host = (parsed.netloc or '').lower()
+    segs = [s for s in (parsed.path or '').split('/') if s]
+
+    def _by_keyword(source: str) -> list[LookupTarget]:
+        """Find the first album/track-style keyword and take the next seg as id."""
+        for i, seg in enumerate(segs):
+            kind = _kind_from_keyword(seg.lower())
+            if kind and i + 1 < len(segs):
+                return [LookupTarget(source, kind, segs[i + 1])]
+        return []
+
+    if 'open.spotify.com' in host:
+        return _by_keyword('spotify')
+
+    if 'music.apple.com' in host or 'itunes.apple.com' in host:
+        # Apple track links are an album URL with ?i=<track-id>; otherwise the
+        # trailing path segment is the album/song id.
+        qs = parse_qs(parsed.query or '')
+        track_id = (qs.get('i') or [None])[0]
+        if track_id:
+            return [LookupTarget('itunes', 'track', track_id)]
+        for i, seg in enumerate(segs):
+            kind = _kind_from_keyword(seg.lower())
+            if kind and i + 1 < len(segs):
+                # Apple's id is the last segment, not necessarily i+1.
+                return [LookupTarget('itunes', kind, segs[-1])]
+        return []
+
+    if 'musicbrainz.org' in host:
+        return _by_keyword('musicbrainz')
+
+    if 'deezer.com' in host:
+        # link.deezer.com short links can't be resolved without a network
+        # redirect; only handle canonical /album/ /track/ paths.
+        return _by_keyword('deezer')
+
+    return []
+
+
+def parse_metadata_identifier(raw: str) -> list[LookupTarget]:
+    """Parse a pasted provider link (or ``spotify:`` URI) into lookup targets.
+
+    Links only — a bare ID has no source/type and is rejected (returns ``[]``).
+    A URL resolves to exactly one target; the list type is kept for the
+    ``spotify:`` URI path and future multi-target patterns.
+    """
+    raw = (raw or '').strip()
+    if not raw:
+        return []
+
+    if raw.lower().startswith('spotify:'):
+        uri = _parse_spotify_uri(raw)
+        return [uri] if uri else []
+
+    lowered = raw.lower()
+    looks_like_url = (
+        '://' in raw
+        or lowered.startswith('www.')
+        or any(host in lowered for host in _KNOWN_HOSTS)
+    )
+    if looks_like_url:
+        url = raw if '://' in raw else f'https://{raw}'
+        return _parse_url(url)
+
+    # Bare ID (or anything we don't recognize as a link) — rejected.
+    return []
+
+
+# --------------------------------------------------------------------------
+# Shaping — project a get-by-id dict onto the dropdown's card shape
+# --------------------------------------------------------------------------
+
+def _join_artists(artists: Any) -> str:
+    """Normalize an artists field (list of str OR list of {'name': ...}) to a
+    display string."""
+    names: list[str] = []
+    for a in artists or []:
+        if isinstance(a, dict):
+            n = a.get('name')
+        else:
+            n = a
+        if n:
+            names.append(str(n))
+    return ', '.join(names) if names else 'Unknown Artist'
+
+
+def _first_image(d: dict) -> str:
+    """Pull the first image URL from a Spotify-shaped images list."""
+    imgs = d.get('images') or []
+    if imgs and isinstance(imgs[0], dict):
+        return imgs[0].get('url', '') or ''
+    return d.get('image_url', '') or ''
+
+
+def album_dict_to_card(d: dict) -> dict:
+    """Project a get_album / get_album_metadata dict onto the album card shape
+    (mirrors ``core/search/sources.py`` ``search_kind('albums')``)."""
+    return {
+        'id': str(d.get('id', '')),
+        'name': d.get('name', ''),
+        'artist': _join_artists(d.get('artists')),
+        'image_url': _first_image(d),
+        'release_date': d.get('release_date', ''),
+        'total_tracks': d.get('total_tracks', 0),
+        'album_type': d.get('album_type', 'album'),
+        'format': d.get('format'),
+        'country': d.get('country'),
+        'status': d.get('status'),
+        'label': d.get('label'),
+        'disambiguation': d.get('disambiguation'),
+        'release_group_id': d.get('release_group_id'),
+        'external_urls': d.get('external_urls') or {},
+    }
+
+
+def track_dict_to_card(d: dict) -> dict:
+    """Project a get_track_details dict onto the track card shape (mirrors
+    ``core/search/sources.py`` ``search_kind('tracks')``)."""
+    album = d.get('album')
+    if isinstance(album, dict):
+        album_name = album.get('name', '')
+        image_url = _first_image(album)
+        release_date = album.get('release_date', '')
+    else:
+        album_name = album or ''
+        image_url = _first_image(d)
+        release_date = d.get('release_date', '')
+    return {
+        'id': str(d.get('id', '')),
+        'name': d.get('name', ''),
+        'artist': _join_artists(d.get('artists')),
+        'album': album_name,
+        'duration_ms': d.get('duration_ms', 0),
+        'image_url': image_url or _first_image(d),
+        'release_date': release_date,
+        'external_urls': d.get('external_urls') or {},
+    }
+
+
+def artist_dict_to_card(d: dict) -> dict:
+    """Project a get_artist / get_artist_info dict onto the artist card shape
+    (mirrors ``core/search/sources.py`` ``search_kind('artists')``)."""
+    return {
+        'id': str(d.get('id', '')),
+        'name': d.get('name', ''),
+        'image_url': _first_image(d),
+        'external_urls': d.get('external_urls') or {},
+    }
+
+
+# --------------------------------------------------------------------------
+# Fetch dispatch — per-source method names differ slightly
+# --------------------------------------------------------------------------
+
+def _fetch_album(client: Any, source: str, identifier: str) -> Optional[dict]:
+    """Fetch album metadata by id. Deezer names the method differently; the
+    rest share ``get_album``. ``include_tracks=False`` keeps the lookup cheap
+    (the modal re-fetches the full tracklist on open)."""
+    if source == 'deezer':
+        return client.get_album_metadata(identifier, include_tracks=False)
+    if source in ('itunes', 'musicbrainz'):
+        return client.get_album(identifier, include_tracks=False)
+    return client.get_album(identifier)  # spotify
+
+
+def _fetch_track(client: Any, source: str, identifier: str) -> Optional[dict]:
+    """Fetch track metadata by id — uniform across all supported sources."""
+    return client.get_track_details(identifier)
+
+
+def _fetch_artist(client: Any, source: str, identifier: str) -> Optional[dict]:
+    """Fetch artist metadata by id. Deezer names the method differently; the
+    rest share ``get_artist``."""
+    if source == 'deezer':
+        return client.get_artist_info(identifier)
+    return client.get_artist(identifier)
+
+
+# Shown in the dropdown's empty state so the user knows what to do next.
+_MSG_NOT_A_LINK = (
+    'Paste a full link from Spotify, Apple Music, MusicBrainz, or Deezer '
+    '(a bare ID is ambiguous).'
+)
+_MSG_NOT_FOUND = "Couldn't resolve that link — double-check it's correct."
+
+
+def _empty_result(raw: str, source: str = '', message: str = '') -> dict:
+    return {
+        'source': source,
+        'albums': [],
+        'tracks': [],
+        'artists': [],
+        'available': False,
+        'query': raw,
+        'message': message,
+    }
+
+
+def _hit_result(raw: str, source: str, key: str, card: dict) -> dict:
+    """Build a success result carrying the single resolved card under ``key``
+    ('albums' | 'tracks' | 'artists'); the other lists stay empty."""
+    result = {
+        'source': source,
+        'albums': [],
+        'tracks': [],
+        'artists': [],
+        'available': True,
+        'query': raw,
+        'message': '',
+    }
+    result[key] = [card]
+    return result
+
+
+def resolve_identifier(
+    raw: str,
+    deps: Any,
+    client_resolver: Optional[Callable[[str], Any]] = None,
+) -> dict:
+    """Resolve a pasted provider link to a single album, track, or artist card.
+
+    Returns a dropdown-compatible dict:
+    ``{source, albums, tracks, artists, available, query, message}``. ``available`` is
+    True iff a source returned a hit; the first resolving target wins, so the
+    result carries exactly one card (and the ``source`` that owns it).
+    ``message`` is a user-facing hint when nothing resolved.
+
+    ``client_resolver`` maps a source name to a client (or None). It defaults
+    to the orchestrator's ``resolve_client``; tests inject fakes.
+    """
+    if client_resolver is None:
+        from core.search.orchestrator import resolve_client
+
+        def client_resolver(source: str) -> Any:  # noqa: E306
+            return resolve_client(source, deps)[0]
+
+    targets = parse_metadata_identifier(raw)
+    if not targets:
+        logger.info(f"Link/ID resolve: not a recognized link {raw!r}")
+        return _empty_result(raw, message=_MSG_NOT_A_LINK)
+
+    for target in targets:
+        try:
+            client = client_resolver(target.source)
+        except Exception as e:
+            logger.debug(f"Link/ID resolve: client for {target.source} failed: {e}")
+            client = None
+        if client is None:
+            continue
+
+        kinds = (target.kind,) if target.kind else ('album', 'track')
+        for kind in kinds:
+            try:
+                if kind == 'album':
+                    data = _fetch_album(client, target.source, target.id)
+                    if data:
+                        return _hit_result(raw, target.source, 'albums',
+                                           album_dict_to_card(data))
+                elif kind == 'artist':
+                    data = _fetch_artist(client, target.source, target.id)
+                    if data:
+                        return _hit_result(raw, target.source, 'artists',
+                                           artist_dict_to_card(data))
+                else:
+                    data = _fetch_track(client, target.source, target.id)
+                    if data:
+                        return _hit_result(raw, target.source, 'tracks',
+                                           track_dict_to_card(data))
+            except Exception as e:
+                logger.debug(
+                    f"Link/ID resolve: {target.source} {kind} {target.id} failed: {e}"
+                )
+
+    logger.info(f"Link/ID resolve: no source resolved {raw!r}")
+    return _empty_result(raw, source=targets[0].source, message=_MSG_NOT_FOUND)

core/search/orchestrator.py

@@ -65,7 +65,9 @@ class SearchDeps:
 def resolve_client(source_name: str, deps: SearchDeps) -> tuple[Any, bool]:
     """Return (client, is_available) for an explicit metadata source request."""
     if source_name == 'spotify':
-        if deps.spotify_client and deps.spotify_client.is_spotify_authenticated():
+        # Available when real auth OR the no-creds SpotipyFree fallback can serve
+        # (the client routes to free internally when auth is missing/limited).
+        if deps.spotify_client and deps.spotify_client.is_spotify_metadata_available():
             return deps.spotify_client, True
         return None, False
     if source_name == 'itunes':

core/soulseek_client.py

@@ -1613,7 +1613,10 @@ class SoulseekClient(DownloadSourcePlugin):
             return result
 
         _emit('staging', release=getattr(picked, 'album_title', folder_path) if picked else folder_path)
-        copied = copy_audio_files_atomically(completed, Path(staging_dir))
+        # remove_source=True: clean slskd's completed files once staged so they
+        # don't pile up in the download folder (#796). Soulseek has no seeding,
+        # unlike the torrent/usenet bundle paths which keep their originals.
+        copied = copy_audio_files_atomically(completed, Path(staging_dir), remove_source=True)
         if not copied:
             result['error'] = 'No Soulseek album files copied to staging'
             return result

core/spotify_client.py

@@ -569,6 +569,72 @@ class SpotifyClient:
             return self._itunes  # Fall back to iTunes if no Discogs token
         return self._itunes
 
+    def _free_selected(self) -> bool:
+        """Whether the user picked 'Spotify Free' as their metadata source
+        (the no-creds option, for when they haven't connected Spotify)."""
+        try:
+            return bool(config_manager.get('metadata.spotify_free', False))
+        except Exception:
+            return False
+
+    def _free_installed(self) -> bool:
+        from core.spotify_free_metadata import spotify_free_installed
+        return spotify_free_installed()
+
+    def _free_wanted(self) -> bool:
+        """Does the user actually want the free source? OPT-IN: only when they
+        picked 'Spotify Free'. This keeps free from auto-scraping for anyone who
+        didn't choose it — a plain-'Spotify' user just waits out a rate-limit ban
+        as before. A user on 'Spotify Free' who also connects an account uses the
+        official account normally and free only bridges their bans."""
+        return self._free_selected()
+
+    def _free_available(self) -> bool:
+        """Free CAN serve: package installed AND the user wants Spotify."""
+        return self._free_installed() and self._free_wanted()
+
+    def is_spotify_metadata_available(self) -> bool:
+        """Whether SoulSync can serve Spotify metadata — real auth OR the
+        no-creds source. Availability gates (search resolve, enrichment worker,
+        watchlist) use THIS instead of ``is_spotify_authenticated()`` so the
+        free source is reachable. Does NOT change auth semantics."""
+        from core.spotify_free_metadata import should_offer_spotify_metadata
+        try:
+            authed = self.is_spotify_authenticated()
+        except Exception:
+            authed = False
+        return should_offer_spotify_metadata(authed, self._free_available())
+
+    def _free_active(self) -> bool:
+        """Whether the no-creds source may serve THIS request: free available
+        AND official can't (no auth, or rate-limited). ``is_spotify_authenticated()``
+        already returns False during a rate-limit ban; the explicit rate-limit
+        term covers the brief window before the auth cache refreshes. When authed
+        + healthy the official path returns first, so this never opens.
+
+        Two activations fall out of this: a no-auth user who chose Spotify Free
+        (free is their source), and a connected user mid-rate-limit (free bridges
+        the ban) — see _free_wanted()."""
+        from core.spotify_free_metadata import should_use_free_fallback
+        if not self._free_available():
+            return False
+        try:
+            authed = self.is_spotify_authenticated()
+        except Exception:
+            authed = False
+        return should_use_free_fallback(authed, _is_globally_rate_limited())
+
+    @property
+    def _free_meta(self):
+        """Lazy SpotipyFree-backed metadata client (soft import — absence is
+        not fatal; methods degrade to the iTunes/Deezer fallback)."""
+        client = getattr(self, '_free_meta_client', None)
+        if client is None:
+            from core.spotify_free_metadata import SpotifyFreeMetadataClient
+            client = SpotifyFreeMetadataClient()
+            self._free_meta_client = client
+        return client
+
     def reload_config(self):
         """Reload configuration and re-initialize client"""
         self._invalidate_auth_cache()
@@ -1276,6 +1342,17 @@ class SpotifyClient:
                 logger.error(f"Error searching tracks via Spotify: {e}")
                 # Fall through to fallback
 
+        # No-creds Spotify (SpotipyFree) before the iTunes/Deezer fallback —
+        # only when official Spotify is unavailable (no auth / rate-limited).
+        if allow_fallback and self._free_active():
+            try:
+                objs = [Track.from_spotify_track(t)
+                        for t in self._free_meta.search_tracks(query, effective_limit)]
+                if objs:
+                    return objs
+            except Exception as e:
+                logger.debug("SpotipyFree track search failed: %s", e)
+
         # Fallback (iTunes or Deezer — configured in settings)
         if allow_fallback:
             logger.debug(f"Using {self._fallback_source} fallback for track search: {query}")
@@ -1336,6 +1413,21 @@ class SpotifyClient:
                 logger.error(f"Error searching artists via Spotify: {e}")
                 # Fall through to iTunes fallback
 
+        # No-creds Spotify (SpotipyFree): keep Spotify catalog/matching when
+        # official Spotify can't serve us (no auth / rate-limited), before the
+        # iTunes/Deezer fallback. Gated by _free_active() so it never runs while
+        # auth is healthy.
+        if allow_fallback and self._free_active():
+            try:
+                objs = [Artist.from_spotify_artist(a)
+                        for a in self._free_meta.search_artists(query, limit)]
+                if objs:
+                    query_lower = query.lower().strip()
+                    objs.sort(key=lambda a: (0 if a.name.lower().strip() == query_lower else 1))
+                    return objs
+            except Exception as e:
+                logger.debug("SpotipyFree artist search failed: %s", e)
+
         # Fallback (iTunes or Deezer)
         if allow_fallback:
             logger.debug(f"Using {self._fallback_source} fallback for artist search: {query}")
@@ -1437,6 +1529,13 @@ class SpotifyClient:
                 logger.error(f"Error fetching track details via Spotify: {e}")
                 # Fall through to iTunes fallback
 
+        # No-creds Spotify (SpotipyFree) for a real Spotify track id when
+        # official Spotify is unavailable (no auth / rate-limited).
+        if allow_fallback and self._free_active() and not self._is_itunes_id(track_id):
+            free = self._free_meta.get_track_details(track_id)
+            if free:
+                return free
+
         # Fallback - only if ID is numeric (non-Spotify format)
         if allow_fallback and self._is_itunes_id(track_id):
             logger.debug(f"Using {fallback_src} fallback for track details: {track_id}")
@@ -1528,6 +1627,13 @@ class SpotifyClient:
                 logger.error(f"Error fetching album via Spotify: {e}")
                 # Fall through to fallback
 
+        # No-creds Spotify (SpotipyFree) for a real Spotify album id when
+        # official Spotify is unavailable (no auth / rate-limited).
+        if allow_fallback and self._free_active() and not self._is_itunes_id(album_id):
+            free = self._free_meta.get_album(album_id)
+            if free:
+                return free
+
         # Fallback - only if ID is numeric (non-Spotify format)
         if allow_fallback and self._is_itunes_id(album_id):
             logger.debug(f"Using {fallback_src} fallback for album: {album_id}")
@@ -1605,6 +1711,13 @@ class SpotifyClient:
                 logger.error(f"Error fetching album tracks via Spotify: {e}")
                 # Fall through to iTunes fallback
 
+        # No-creds Spotify (SpotipyFree) for a real Spotify album id when
+        # official Spotify is unavailable (no auth / rate-limited).
+        if allow_fallback and self._free_active() and not self._is_itunes_id(album_id):
+            free = self._free_meta.get_album_tracks(album_id)
+            if free:
+                return free
+
         # Fallback - only if ID is numeric (non-Spotify format)
         if allow_fallback and self._is_itunes_id(album_id):
             logger.debug(f"Using {fallback_src} fallback for album tracks: {album_id}")
@@ -1691,6 +1804,18 @@ class SpotifyClient:
                 logger.error(f"Error fetching artist albums via Spotify: {e}")
                 # Fall through to iTunes fallback
 
+        # No-creds Spotify (SpotipyFree) for a real Spotify artist id when
+        # official Spotify is unavailable (no auth / rate-limited). The free
+        # discography is already album-shaped — project to Album dataclasses.
+        if allow_fallback and self._free_active() and not self._is_itunes_id(artist_id):
+            try:
+                free = [Album.from_spotify_album(a)
+                        for a in self._free_meta.get_artist_albums_list(artist_id, limit)]
+                if free:
+                    return free
+            except Exception as e:
+                logger.debug("SpotipyFree artist albums failed: %s", e)
+
         # Fallback - only if ID is numeric (non-Spotify format)
         if allow_fallback and self._is_itunes_id(artist_id):
             logger.debug(f"Using {fallback_src} fallback for artist albums: {artist_id}")
@@ -1745,6 +1870,13 @@ class SpotifyClient:
                 logger.error(f"Error fetching artist via Spotify: {e}")
                 # Fall through to iTunes fallback
 
+        # No-creds Spotify (SpotipyFree) for a real Spotify artist id when
+        # official Spotify is unavailable (no auth / rate-limited).
+        if allow_fallback and self._free_active() and not self._is_itunes_id(artist_id):
+            free = self._free_meta.get_artist(artist_id)
+            if free:
+                return free
+
         # Fallback - only if ID is numeric (non-Spotify format)
         if allow_fallback and self._is_itunes_id(artist_id):
             logger.debug(f"Using {fallback_src} fallback for artist: {artist_id}")

core/spotify_free_metadata.py

@@ -0,0 +1,224 @@
+"""PROTOTYPE — no-credentials Spotify metadata via SpotipyFree / spotapi.
+
+Goal: stand in as a READ-ONLY Spotify metadata source when the user has no
+Spotify auth (or is rate-limited), mapping SpotipyFree's outputs onto the same
+Spotify-compatible shapes the rest of SoulSync already consumes
+(see core/spotify_client.py + core/search/sources.py).
+
+Unofficial / web-player scraping — best-effort, fragile, and NOT a substitute
+for the user-account features (those need a real login).
+
+Capabilities (verified live, 2026-06):
+  search_tracks          ✅ SpotipyFree.search (already official-shaped)
+  search_artists         ✅ spotapi.Public().artist_search (normalized here)
+  search_albums          ❌ no album-name search exists upstream → returns []
+  get_album              ✅ SpotipyFree.album (already official-shaped)
+  get_artist_albums_list ✅ SpotipyFree.artist_albums (already official-shaped)
+  get_track_details      ✅ SpotipyFree.track (already official-shaped)
+  get_artist             ✅ SpotipyFree.artist (RAW GraphQL → normalized here)
+  get_artist_top_tracks  ❌ unavailable
+  audio_features         ❌ unavailable (Spotify deprecated it anyway)
+
+This module is import-safe even when SpotipyFree isn't installed — it
+soft-imports inside the client factory.
+"""
+
+from __future__ import annotations
+
+import importlib.util
+import logging
+from typing import Any, Optional
+
+logger = logging.getLogger(__name__)
+
+_installed_cache: Optional[bool] = None
+
+
+def spotify_free_installed() -> bool:
+    """Cheap, cached check: is the optional SpotipyFree package importable?
+
+    Used by the availability gates — never constructs a client or hits the
+    network. Absence just means we degrade to the iTunes/Deezer fallback.
+    """
+    global _installed_cache
+    if _installed_cache is None:
+        _installed_cache = importlib.util.find_spec('SpotipyFree') is not None
+    return _installed_cache
+
+
+def should_use_free_fallback(authenticated: bool, rate_limited: bool) -> bool:
+    """The per-request gate: the no-creds SpotipyFree source may serve a request
+    ONLY when official Spotify can't — i.e. the user has no Spotify auth, or
+    we're currently rate-limited. When authed AND healthy the official path
+    returns before any fallback, so this never opens.
+    """
+    return (not authenticated) or rate_limited
+
+
+def should_offer_spotify_metadata(authenticated: bool, free_available: bool) -> bool:
+    """The availability gate: SoulSync can serve *some* Spotify metadata when
+    either real auth is present, or the no-creds fallback is available. The
+    upstream gates (search resolve, enrichment worker, watchlist) use this so
+    the fallback is actually reachable — without changing what
+    ``is_spotify_authenticated()`` means anywhere.
+    """
+    return authenticated or free_available
+
+
+def should_block_rate_limited_resume(rate_limited: bool, metadata_available: bool) -> bool:
+    """Whether to refuse resuming the Spotify enrichment worker.
+
+    The worker's own loop bridges to the no-creds free source during a ban
+    (its rate-limit guard checks ``is_spotify_metadata_available()``). The
+    resume button must mirror that: block ONLY when rate-limited AND nothing
+    can serve (plain auth, no free) — otherwise resuming just sleeps. When the
+    free fallback is available, ``metadata_available`` is True during a ban
+    (``is_spotify_authenticated()`` returns False while banned), so resume is
+    allowed and the worker bridges via free.
+    """
+    return rate_limited and not metadata_available
+
+
+# --------------------------------------------------------------------------
+# Normalizers (pure — unit-testable against captured fixtures)
+# --------------------------------------------------------------------------
+
+def normalize_artist(raw: dict) -> dict:
+    """Map a raw SpotipyFree/spotapi artist object (from ``artist()`` or an
+    ``artist_search`` item's ``data``) onto the Spotify-compatible artist dict
+    SoulSync expects: ``{id, name, images, genres, followers, external_urls}``.
+
+    Artist-search items carry no usable image (only color swatches), so
+    ``images`` may be empty there — SoulSync lazy-loads artist art separately.
+    Genres aren't provided by the web player at all.
+    """
+    raw = raw or {}
+    profile = raw.get('profile') or {}
+    uri = raw.get('uri') or ''
+    artist_id = raw.get('id') or (uri.split(':')[-1] if uri else '')
+    name = profile.get('name') or raw.get('name') or ''
+
+    images = []
+    avatar = (raw.get('visuals') or {}).get('avatarImage') or {}
+    for src in (avatar.get('sources') or []):
+        if src.get('url'):
+            images.append({
+                'url': src['url'],
+                'height': src.get('height'),
+                'width': src.get('width'),
+            })
+
+    followers = (raw.get('stats') or {}).get('followers')
+
+    return {
+        'id': str(artist_id),
+        'name': name,
+        'images': images,
+        'genres': [],  # web player doesn't expose genres
+        'followers': {'total': followers or 0},
+        'external_urls': (
+            {'spotify': f'https://open.spotify.com/artist/{artist_id}'}
+            if artist_id else {}
+        ),
+    }
+
+
+# --------------------------------------------------------------------------
+# Client
+# --------------------------------------------------------------------------
+
+class SpotifyFreeMetadataClient:
+    """Read-only Spotify metadata via SpotipyFree, normalized to SoulSync's
+    Spotify-compatible shapes. Methods mirror the metadata-source interface."""
+
+    def __init__(self):
+        self._sf = None       # SpotipyFree.Spotify instance
+        self._public = None   # spotapi.Public() for artist_search
+
+    # -- lazy clients (soft import; absence is not fatal) ------------------
+    def _sf_client(self):
+        if self._sf is None:
+            from SpotipyFree import Spotify  # optional, user-installed
+            self._sf = Spotify()
+        return self._sf
+
+    def _public_client(self):
+        if self._public is None:
+            import spotapi
+            self._public = spotapi.Public()
+        return self._public
+
+    def is_available(self) -> bool:
+        try:
+            self._sf_client()
+            return True
+        except Exception as e:
+            logger.debug(f"SpotipyFree unavailable: {e}")
+            return False
+
+    # -- search -----------------------------------------------------------
+    def search_tracks(self, query: str, limit: int = 10) -> list[dict]:
+        try:
+            res = self._sf_client().search(query, limit=limit) or {}
+            items = ((res.get('tracks') or {}).get('items')) or []
+            return items[:limit]
+        except Exception as e:
+            logger.debug(f"SpotipyFree search_tracks failed: {e}")
+            return []
+
+    def search_artists(self, query: str, limit: int = 10) -> list[dict]:
+        try:
+            pages = self._public_client().artist_search(query)
+            first = next(iter(pages), [])
+            out = []
+            for item in first[:limit]:
+                data = item.get('data') if isinstance(item, dict) else None
+                if data:
+                    out.append(normalize_artist(data))
+            return out
+        except Exception as e:
+            logger.debug(f"SpotipyFree search_artists failed: {e}")
+            return []
+
+    def search_albums(self, query: str, limit: int = 10) -> list[dict]:
+        # No album-name search exists in SpotipyFree/spotapi. Albums are only
+        # reachable by id or via an artist's discography.
+        return []
+
+    # -- entity lookups ---------------------------------------------------
+    def get_album(self, album_id: str, include_tracks: bool = True) -> Optional[dict]:
+        try:
+            return self._sf_client().album(album_id)
+        except Exception as e:
+            logger.debug(f"SpotipyFree get_album({album_id}) failed: {e}")
+            return None
+
+    def get_track_details(self, track_id: str) -> Optional[dict]:
+        try:
+            return self._sf_client().track(track_id)
+        except Exception as e:
+            logger.debug(f"SpotipyFree get_track_details({track_id}) failed: {e}")
+            return None
+
+    def get_album_tracks(self, album_id: str) -> Optional[dict]:
+        try:
+            return self._sf_client().album_tracks(album_id)
+        except Exception as e:
+            logger.debug(f"SpotipyFree get_album_tracks({album_id}) failed: {e}")
+            return None
+
+    def get_artist(self, artist_id: str) -> Optional[dict]:
+        try:
+            raw = self._sf_client().artist(artist_id)
+            return normalize_artist(raw) if raw else None
+        except Exception as e:
+            logger.debug(f"SpotipyFree get_artist({artist_id}) failed: {e}")
+            return None
+
+    def get_artist_albums_list(self, artist_id: str, limit: int = 50) -> list[dict]:
+        try:
+            res = self._sf_client().artist_albums(artist_id) or {}
+            return (res.get('items') or [])[:limit]
+        except Exception as e:
+            logger.debug(f"SpotipyFree get_artist_albums_list({artist_id}) failed: {e}")
+            return []

core/spotify_worker.py

@@ -9,7 +9,12 @@ from datetime import datetime, date, timedelta
 from utils.logging_config import get_logger
 from database.music_database import MusicDatabase
 from core.spotify_client import SpotifyClient, SpotifyRateLimitError
-from core.worker_utils import interruptible_sleep, set_album_api_track_count
+from core.worker_utils import (
+    ARTIST_NAME_MATCH_THRESHOLD,
+    interruptible_sleep,
+    set_album_api_track_count,
+    source_id_conflict,
+)
 from core.enrichment.manual_match_honoring import honor_stored_match
 
 logger = get_logger("spotify_worker")
@@ -121,11 +126,19 @@ class SpotifyWorker:
             rate_limit_info = self.client.get_rate_limit_info() if rate_limited else None
             in_cooldown = self.client.get_post_ban_cooldown_remaining() > 0
             authenticated = self.client.sp is not None
+            # Is the worker still serving via the no-creds Spotify Free source
+            # despite the real-API ban? Only check WHEN rate-limited: during a
+            # ban is_spotify_authenticated() returns False without an API probe,
+            # so is_spotify_metadata_available() reduces to "is free available"
+            # (no quota cost). Lets the UI show "via Spotify Free" instead of a
+            # misleading "rate limited / waiting" while the worker keeps matching.
+            using_free = bool(rate_limited and self.client.is_spotify_metadata_available())
         except Exception:
             authenticated = False
             rate_limited = False
             rate_limit_info = None
             in_cooldown = False
+            using_free = False
 
         return {
             'enabled': True,
@@ -134,6 +147,7 @@ class SpotifyWorker:
             'idle': is_idle,
             'authenticated': authenticated,
             'rate_limited': rate_limited,
+            'using_free': using_free,
             'rate_limit': rate_limit_info,
             'daily_budget': self._get_daily_budget_info(),
             'current_item': self.current_item,
@@ -181,16 +195,33 @@ class SpotifyWorker:
                     interruptible_sleep(self._stop_event, 1)
                     continue
 
-                # Rate limit guard — if globally rate limited, sleep until ban expires
-                if self.client.is_rate_limited():
+                # Rate limit guard — if globally rate limited, sleep until ban
+                # expires. EXCEPT: when Spotify Free is available it bridges the
+                # ban (is_spotify_metadata_available() is True via the no-creds
+                # source, and the client routes there), so we keep enriching
+                # instead of stalling. Purely additive: with Spotify Free off,
+                # is_spotify_metadata_available() is False during a ban and this
+                # sleeps exactly as before.
+                if self.client.is_rate_limited() and not self.client.is_spotify_metadata_available():
                     info = self.client.get_rate_limit_info()
                     remaining = info['remaining_seconds'] if info else 60
                     logger.debug(f"Spotify globally rate limited, sleeping {remaining}s...")
                     interruptible_sleep(self._stop_event, min(remaining, 60))  # Check again every 60s max
                     continue
 
-                # Daily budget guard — worker-only cap to avoid saturating Spotify rate limits
-                if self._is_daily_budget_exhausted():
+                # Is the worker serving via the no-creds Spotify Free source this
+                # iteration? The daily budget and post-ban cooldown both exist to
+                # protect the REAL authenticated API from bans — they don't apply
+                # to free (a different, anonymous path). Computed once and reused
+                # below; the loop already probes auth, so no extra quota cost.
+                try:
+                    free_serving = self.client._free_active()
+                except Exception:
+                    free_serving = False
+
+                # Daily budget guard — worker-only cap to avoid saturating the REAL
+                # Spotify API. Skipped while serving via free (free isn't that API).
+                if not free_serving and self._is_daily_budget_exhausted():
                     budget = self._get_daily_budget_info()
                     resets_in = budget['resets_in_seconds']
                     logger.info(f"Daily enrichment budget exhausted ({budget['used']}/{budget['limit']}), "
@@ -199,8 +230,9 @@ class SpotifyWorker:
                     continue
 
                 # Post-ban cooldown guard — after ban expires, wait before resuming
-                # to avoid immediately re-triggering the rate limit
-                cooldown = self.client.get_post_ban_cooldown_remaining()
+                # to avoid immediately re-triggering the rate limit. Only matters
+                # for the real API, so skip it while serving via free.
+                cooldown = 0 if free_serving else self.client.get_post_ban_cooldown_remaining()
                 if cooldown > 0:
                     logger.debug(f"Post-ban cooldown active ({cooldown}s left), sleeping...")
                     interruptible_sleep(self._stop_event, min(cooldown, 60))
@@ -210,10 +242,12 @@ class SpotifyWorker:
                 # We intentionally avoid calling is_spotify_authenticated() here
                 # because it makes an API probe that can re-trigger rate limits
                 # and lock users in an infinite rate-limit loop.
-                if not self.client.is_spotify_authenticated():
+                # Available = real auth OR the no-creds SpotipyFree fallback
+                # (enrichment is metadata-only, so the free source can serve it).
+                if not self.client.is_spotify_metadata_available():
                     self.client.reload_config()
-                    if not self.client.is_spotify_authenticated():
-                        logger.debug("Spotify not authenticated, sleeping 30s...")
+                    if not self.client.is_spotify_metadata_available():
+                        logger.debug("Spotify metadata unavailable, sleeping 30s...")
                         interruptible_sleep(self._stop_event, 30)
                         continue
 
@@ -239,7 +273,10 @@ class SpotifyWorker:
                     continue
 
                 self._process_item(item)
-                self._increment_daily_budget()
+                # Only real-API work counts toward the daily cap — free-served
+                # items don't touch the authenticated API's quota.
+                if not free_serving:
+                    self._increment_daily_budget()
                 interruptible_sleep(self._stop_event, self.inter_item_sleep)
 
             except SpotifyRateLimitError:
@@ -483,12 +520,14 @@ class SpotifyWorker:
             logger.debug(f"No Spotify results for artist '{artist_name}'")
             return
 
-        # Find best fuzzy match — score all candidates, pick highest above threshold
+        # Find best fuzzy match — score all candidates, pick highest above the
+        # (stricter, artist-specific) threshold so short-name false positives
+        # like "ODESZA"/"odessa" don't slip through.
         best_obj = None
         best_score = 0
         for artist_obj in results:
             score = self._name_similarity(artist_name, artist_obj.name)
-            if score >= self.name_similarity_threshold and score > best_score:
+            if score >= ARTIST_NAME_MATCH_THRESHOLD and score > best_score:
                 best_obj = artist_obj
                 best_score = score
 
@@ -498,6 +537,19 @@ class SpotifyWorker:
                 self._mark_status('artist', artist_id, 'error')
                 self.stats['errors'] += 1
                 return
+            # Don't assign a Spotify id another (differently-named) artist
+            # already holds — prevents one id smeared across artists.
+            conflict = source_id_conflict(
+                self.db, 'spotify_artist_id', best_obj.id, artist_id, artist_name
+            )
+            if conflict:
+                self._mark_status('artist', artist_id, 'not_found')
+                self.stats['not_found'] += 1
+                logger.debug(
+                    f"Artist '{artist_name}' -> Spotify {best_obj.id} skipped: "
+                    f"already claimed by '{conflict}'"
+                )
+                return
             self._update_artist(artist_id, best_obj)
             self.stats['matched'] += 1
             logger.info(f"Matched artist '{artist_name}' -> Spotify ID: {best_obj.id} (score: {best_score:.2f})")

core/sync/match_overrides.py

@@ -24,6 +24,10 @@ from __future__ import annotations
 
 from typing import Any, Callable, Dict, List, Optional
 
+from utils.logging_config import get_logger
+
+logger = get_logger("sync.match_overrides")
+
 
 def resolve_match_overrides(
     source_tracks: List[Dict[str, Any]],
@@ -117,3 +121,76 @@ def record_manual_match(
         ))
     except Exception:
         return False
+
+
+def resolve_durable_match_server_id(
+    db: Any,
+    profile_id: int,
+    source_track_id: str,
+    server_source: str,
+    valid_server_ids: set,
+) -> Optional[str]:
+    """Current server track id for a DURABLE manual library match, or None.
+
+    Unlike ``sync_match_cache`` (wiped on every rescan), the
+    ``manual_library_track_matches`` table survives a scan — so consulting it
+    here is what makes a user's Find & Add / manual match persist across a
+    library rescan (#787). If the stored ``library_track_id`` went stale
+    (a rescan re-keyed the track — common on Jellyfin/Navidrome), re-resolve
+    it from the stored file path and self-heal the row so the next lookup is
+    a direct hit.
+
+    Pure helper: ``db`` is injected. ``valid_server_ids`` is the set of
+    string ids that currently exist in the server playlist's track list —
+    a re-resolved id is only returned if it's actually present. Never raises.
+    """
+    if not source_track_id:
+        return None
+    finder = getattr(db, "find_manual_library_match_by_source_track_id", None)
+    if finder is None:
+        return None
+    try:
+        match = finder(profile_id, str(source_track_id), server_source or "")
+    except Exception:
+        return None
+    if not match:
+        return None
+
+    lib_id = match.get("library_track_id")
+    if lib_id is not None and str(lib_id) in valid_server_ids:
+        return str(lib_id)
+
+    # Stale pointer — re-resolve via the stored file path and self-heal.
+    file_path = match.get("library_file_path")
+    resolver = getattr(db, "find_track_id_by_file_path", None)
+    if file_path and resolver is not None:
+        try:
+            new_id = resolver(file_path)
+        except Exception:
+            new_id = None
+        if new_id and str(new_id) in valid_server_ids:
+            _self_heal_match_id(db, match, str(new_id))
+            return str(new_id)
+    return None
+
+
+def _self_heal_match_id(db: Any, match: Dict[str, Any], new_library_track_id: str) -> None:
+    """Rewrite a manual match's library_track_id after re-resolution. Best-effort."""
+    saver = getattr(db, "save_manual_library_match", None)
+    if saver is None:
+        return
+    try:
+        saver(
+            match.get("profile_id", 1),
+            match.get("source", ""),
+            match.get("source_track_id", ""),
+            new_library_track_id,
+            source_title=match.get("source_title"),
+            source_artist=match.get("source_artist"),
+            source_album=match.get("source_album"),
+            source_context_json=match.get("source_context_json"),
+            server_source=match.get("server_source", ""),
+            library_file_path=match.get("library_file_path"),
+        )
+    except Exception as e:
+        logger.debug("manual match self-heal failed: %s", e)

core/sync/playlist_edit.py

@@ -71,4 +71,64 @@ def remove_one_occurrence(
     return ids, False
 
 
-__all__ = ["plan_playlist_add", "remove_one_occurrence"]
+def plan_playlist_reconcile(
+    current_ids: List[str],
+    desired_ids: List[str],
+) -> dict:
+    """Plan an in-place reconcile of a server playlist toward a desired tracklist.
+
+    Used by ``sync_mode='reconcile'`` (#792): instead of deleting + recreating
+    the playlist (which destroys its custom image, description, and identity),
+    the caller keeps the existing playlist object and applies only the delta —
+    adding the tracks that are missing and removing the ones no longer in the
+    source. Pure, no I/O.
+
+    Returns ``{'add': [...], 'remove': [...]}`` (both lists of string ids):
+      - ``add``    — desired ids not currently present, in desired order.
+      - ``remove`` — current ids no longer desired (each occurrence kept once;
+                     duplicates of a still-desired id are left for the caller's
+                     dedupe to handle, never mass-removed).
+
+    Order-preserving and duplicate-safe: a desired id already present is not
+    re-added; a current id that's still desired is not removed even if it
+    appears more than once.
+    """
+    desired = [str(t) for t in desired_ids]
+    current = [str(t) for t in current_ids]
+    current_set = set(current)
+    desired_set = set(desired)
+    add = [d for d in desired if d not in current_set]
+    # Preserve order of removal as it appears in the current list; one entry per
+    # id (the caller maps ids back to concrete playlist entries to delete).
+    seen_remove = set()
+    remove = []
+    for c in current:
+        if c not in desired_set and c not in seen_remove:
+            seen_remove.add(c)
+            remove.append(c)
+    return {"add": add, "remove": remove}
+
+
+VALID_SYNC_MODES = ("replace", "append", "reconcile")
+
+
+def normalize_sync_mode(requested, configured, default: str = "replace") -> str:
+    """Resolve the effective playlist sync mode.
+
+    An explicit per-request value wins; otherwise the configured default
+    (Settings > Playlist sync mode); anything unrecognized falls back to
+    ``default``. Keeping ``reconcile`` in ``VALID_SYNC_MODES`` is load-bearing —
+    a validation list that omits it silently downgrades reconcile to replace,
+    which is exactly the #792 regression this helper exists to prevent.
+    """
+    mode = (requested or "") or (configured or "") or default
+    return mode if mode in VALID_SYNC_MODES else default
+
+
+__all__ = [
+    "plan_playlist_add",
+    "remove_one_occurrence",
+    "plan_playlist_reconcile",
+    "normalize_sync_mode",
+    "VALID_SYNC_MODES",
+]

core/tag_writer.py

@@ -136,10 +136,49 @@ def read_file_tags(file_path: str) -> Dict[str, Any]:
     return result
 
 
+# Known placeholder / "we don't really know" metadata values. A match in the
+# DB never warrants overwriting a real value already in the file (issue #800:
+# a mis-grouped track sits under a "Various Artists" / "[Unknown Album]" record,
+# and Write Tags would otherwise stamp that junk over the file's correct tags).
+_PLACEHOLDER_META_VALUES = frozenset({
+    'various artists', 'various artist',
+    'unknown artist', 'unknown album', 'unknown',
+    '[unknown album]', '[unknown artist]', '[unknown]',
+    'untitled album',
+})
+
+
+def is_placeholder_meta(value: Any) -> bool:
+    """True for empty or known-placeholder metadata strings (case-insensitive)."""
+    if value is None:
+        return True
+    s = str(value).strip().lower()
+    return s == '' or s in _PLACEHOLDER_META_VALUES
+
+
+def guard_placeholder_overwrite(db_val: Any, file_val: Any) -> Any:
+    """#800 guard: never replace a real file value with a placeholder.
+
+    Returns ``None`` (skip the write → preserve the file's value) ONLY when the
+    DB value is a placeholder/empty AND the file already holds a real,
+    non-placeholder value. Otherwise returns ``db_val`` unchanged — so a
+    legitimate value still writes, including a genuine ``Various Artists`` album
+    artist on a real compilation (there the file has no conflicting real value,
+    so the guard doesn't fire).
+    """
+    if is_placeholder_meta(db_val) and not is_placeholder_meta(file_val):
+        return None
+    return db_val
+
+
 def build_tag_diff(file_tags: Dict[str, Any], db_data: Dict[str, Any]) -> List[Dict[str, Any]]:
     """
     Compare file tags against DB metadata. Returns a list of diffs:
-    [{ field, file_value, db_value, changed }]
+    [{ field, file_value, db_value, changed, protected }]
+
+    ``protected`` marks a field the #800 guard is holding back: the DB value is
+    a placeholder and the file's real value would be preserved, so it's shown
+    as no-change rather than a wrong overwrite.
     """
     fields = [
         ('title', 'title', 'Title'),
@@ -179,12 +218,22 @@ def build_tag_diff(file_tags: Dict[str, Any], db_data: Dict[str, Any]) -> List[D
         # Only mark as changed if DB has a value AND it differs from file
         # (writer skips fields where DB value is empty, so don't show them as diffs)
         changed = bool(db_str) and file_str != db_str
+
+        # #800 — if the change would replace a real file value with a
+        # placeholder (Various Artists / [Unknown Album] / …), hold it back:
+        # the writer preserves the file's value, so show it as no-change.
+        protected = False
+        if changed and guard_placeholder_overwrite(db_val, file_val) is None:
+            changed = False
+            protected = True
+
         diffs.append({
             'field': label,
             'file_key': file_key,
             'file_value': str(file_val) if file_val is not None else '',
             'db_value': str(db_val) if db_val is not None else '',
             'changed': changed,
+            'protected': protected,
         })
 
     # Cover art — special row
@@ -253,6 +302,23 @@ def write_tags_to_file(file_path: str, db_data: Dict[str, Any],
         artist = db_data.get('track_artist') or db_data.get('artist_name')  # Per-track artist for compilations/DJ mixes
         album = db_data.get('album_title')
         album_artist = db_data.get('artist_name')  # Album artist stays as the album-level artist
+
+        # #800 — never overwrite a real value already in the file with a
+        # placeholder DB value (Various Artists / [Unknown Album] / …). A
+        # mis-grouped track sits under such a record; writing it would destroy
+        # the file's correct tags. Reads the file's current values and skips
+        # only the placeholder-over-real fields (legit values, incl. a genuine
+        # compilation's Various Artists, still write — see guard docstring).
+        try:
+            _current = read_file_tags(file_path)
+        except Exception:
+            _current = {}
+        if not _current.get('error'):
+            title = guard_placeholder_overwrite(title, _current.get('title'))
+            artist = guard_placeholder_overwrite(artist, _current.get('artist'))
+            album = guard_placeholder_overwrite(album, _current.get('album'))
+            album_artist = guard_placeholder_overwrite(album_artist, _current.get('album_artist'))
+
         year = db_data.get('year')
         genres = db_data.get('genres')
         track_num = db_data.get('track_number')
@@ -294,6 +360,24 @@ def write_tags_to_file(file_path: str, db_data: Dict[str, Any],
                                  year, genre_str, track_num, total_tracks,
                                  disc_num, bpm, artists_list=artists_list)
 
+        # Embed already-known source IDs (Spotify / iTunes / MusicBrainz) from
+        # db_data, reusing the canonical import-time frame writer — no API
+        # re-fetch. Only fires when db_data carries id keys, so the plain
+        # "write the core tags" callers are unaffected.
+        _src_meta = {k: db_data[k] for k in (
+            'source', 'source_track_id', 'source_album_id', 'source_artist_id',
+            'spotify_track_id', 'spotify_album_id', 'spotify_artist_id',
+            'itunes_track_id', 'itunes_album_id', 'itunes_artist_id',
+            'musicbrainz_recording_id', 'musicbrainz_release_id',
+        ) if db_data.get(k)}
+        if _src_meta:
+            try:
+                from core.metadata.source import embed_known_source_ids
+                if embed_known_source_ids(audio, _src_meta):
+                    written.append('source_ids')
+            except Exception as e:
+                logger.debug("source-id embed skipped for %s: %s", file_path, e)
+
         # Embed cover art if requested
         if embed_cover:
             art_ok = False

core/tidal_worker.py

@@ -7,7 +7,7 @@ from datetime import datetime, timedelta
 from utils.logging_config import get_logger
 from database.music_database import MusicDatabase
 from core.tidal_client import TidalClient
-from core.worker_utils import interruptible_sleep
+from core.worker_utils import accept_artist_match, interruptible_sleep
 from core.enrichment.manual_match_honoring import honor_stored_match
 
 logger = get_logger("tidal_worker")
@@ -313,13 +313,29 @@ class TidalWorker:
         logger.debug(f"Name similarity: '{query_name}' vs '{result_name}' = {similarity:.2f}")
         return similarity >= self.name_similarity_threshold
 
-    def _verify_artist_id(self, item: Dict[str, Any], result_artist_id) -> bool:
-        """Verify/correct parent artist's Tidal ID based on album/track match"""
+    def _verify_artist_id(self, item: Dict[str, Any], result_artist_id,
+                          result_artist_name: Optional[str] = None) -> bool:
+        """Verify/correct parent artist's Tidal ID based on album/track match.
+
+        Only corrects when the result's artist *name* matches our parent artist —
+        otherwise a collaboration/compilation would stamp the wrong Tidal id onto
+        our artist. See the Deezer fix for the full write-up."""
         parent_tidal_id = item.get('artist_tidal_id')
         if not parent_tidal_id or not result_artist_id:
             return True
 
         if str(result_artist_id) != str(parent_tidal_id):
+            parent_name = item.get('artist') or ''
+            if (result_artist_name and parent_name
+                    and not self._name_matches(parent_name, result_artist_name)):
+                logger.info(
+                    f"Skipping artist-ID correction from {item['type']} "
+                    f"'{item['name']}': result artist '{result_artist_name}' "
+                    f"≠ parent '{parent_name}' (collab/compilation, not a "
+                    f"correction)"
+                )
+                return True
+
             logger.info(
                 f"Artist ID correction from {item['type']} '{item['name']}': "
                 f"updating parent artist Tidal ID from {parent_tidal_id} to {result_artist_id}"
@@ -419,14 +435,19 @@ class TidalWorker:
         result = self.client.search_artist(artist_name)
         if result:
             result_name = result.get('name', '')
-            if self._name_matches(artist_name, result_name):
-                tidal_artist_id = result.get('id')
-                if not tidal_artist_id:
-                    self._mark_status('artist', artist_id, 'error')
-                    self.stats['errors'] += 1
-                    logger.warning(f"Tidal search result for '{artist_name}' has no ID")
-                    return
-
+            tidal_artist_id = result.get('id')
+            ok, reason = accept_artist_match(
+                self.db, 'tidal_id', tidal_artist_id, artist_id, artist_name, result_name,
+            )
+            if not ok:
+                self._mark_status('artist', artist_id, 'not_found')
+                self.stats['not_found'] += 1
+                logger.debug(f"Artist '{artist_name}' not matched: {reason}")
+            elif not tidal_artist_id:
+                self._mark_status('artist', artist_id, 'error')
+                self.stats['errors'] += 1
+                logger.warning(f"Tidal search result for '{artist_name}' has no ID")
+            else:
                 # Fetch full artist details for image
                 full_artist = None
                 try:
@@ -437,10 +458,6 @@ class TidalWorker:
                 self._update_artist(artist_id, result, full_artist)
                 self.stats['matched'] += 1
                 logger.info(f"Matched artist '{artist_name}' -> Tidal ID: {tidal_artist_id}")
-            else:
-                self._mark_status('artist', artist_id, 'not_found')
-                self.stats['not_found'] += 1
-                logger.debug(f"Name mismatch for artist '{artist_name}' (got '{result_name}')")
         else:
             self._mark_status('artist', artist_id, 'not_found')
             self.stats['not_found'] += 1
@@ -479,7 +496,8 @@ class TidalWorker:
                 # Verify artist ID
                 result_artist = result.get('artist', {})
                 result_artist_id = result_artist.get('id') if result_artist else None
-                self._verify_artist_id(item, result_artist_id)
+                result_artist_name = result_artist.get('name') if result_artist else None
+                self._verify_artist_id(item, result_artist_id, result_artist_name)
 
                 # Fetch full album details
                 tidal_album_id = result.get('id')
@@ -533,7 +551,8 @@ class TidalWorker:
                 # Verify artist ID
                 result_artist = result.get('artist', {})
                 result_artist_id = result_artist.get('id') if result_artist else None
-                self._verify_artist_id(item, result_artist_id)
+                result_artist_name = result_artist.get('name') if result_artist else None
+                self._verify_artist_id(item, result_artist_id, result_artist_name)
 
                 # Fetch full track details
                 tidal_track_id = result.get('id')

core/torrent_clients/base.py

@@ -20,6 +20,24 @@ from dataclasses import dataclass
 from typing import List, Optional, Protocol, runtime_checkable
 
 
+def normalize_client_url(raw: str) -> str:
+    """Clean a user-entered WebUI URL into something ``requests`` accepts.
+
+    Users routinely type a bare host like ``192.168.1.5:8080`` or
+    ``qbittorrent.lan:8080`` with no scheme. ``requests`` then raises
+    "No connection adapters were found for '...'" because it can't pick an
+    http/https adapter (a bare ``host:port`` even gets misparsed as
+    ``scheme=host``). Default a missing scheme to ``http://`` and trim a
+    trailing slash. Empty input passes through unchanged.
+    """
+    url = (raw or '').strip()
+    if not url:
+        return ''
+    if '://' not in url:
+        url = 'http://' + url
+    return url.rstrip('/')
+
+
 @dataclass
 class TorrentStatus:
     """Adapter-uniform view of one torrent's live state.

core/torrent_clients/deluge.py

@@ -20,7 +20,7 @@ from typing import Any, List, Optional
 import requests as http_requests
 
 from config.settings import config_manager
-from core.torrent_clients.base import TorrentStatus
+from core.torrent_clients.base import TorrentStatus, normalize_client_url
 from utils.logging_config import get_logger
 
 logger = get_logger("torrent.deluge")
@@ -67,7 +67,7 @@ class DelugeAdapter:
         self._load_config()
 
     def _load_config(self) -> None:
-        self._url = (config_manager.get('torrent_client.url', '') or '').rstrip('/')
+        self._url = normalize_client_url(config_manager.get('torrent_client.url', ''))
         # Deluge's WebUI auth uses a single password, not username+password.
         # We accept whichever field the user filled in — keeps the UI uniform.
         self._password = (

core/torrent_clients/qbittorrent.py

@@ -18,7 +18,7 @@ from typing import List, Optional
 import requests as http_requests
 
 from config.settings import config_manager
-from core.torrent_clients.base import TorrentStatus
+from core.torrent_clients.base import TorrentStatus, normalize_client_url
 from utils.logging_config import get_logger
 
 logger = get_logger("torrent.qbittorrent")
@@ -64,7 +64,7 @@ class QBittorrentAdapter:
         self._load_config()
 
     def _load_config(self) -> None:
-        self._url = (config_manager.get('torrent_client.url', '') or '').rstrip('/')
+        self._url = normalize_client_url(config_manager.get('torrent_client.url', ''))
         self._username = config_manager.get('torrent_client.username', '') or ''
         self._password = config_manager.get('torrent_client.password', '') or ''
         self._category = config_manager.get('torrent_client.category', 'soulsync') or 'soulsync'

core/torrent_clients/transmission.py

@@ -18,7 +18,7 @@ from typing import List, Optional
 import requests as http_requests
 
 from config.settings import config_manager
-from core.torrent_clients.base import TorrentStatus
+from core.torrent_clients.base import TorrentStatus, normalize_client_url
 from utils.logging_config import get_logger
 
 logger = get_logger("torrent.transmission")
@@ -57,7 +57,7 @@ class TransmissionAdapter:
         self._load_config()
 
     def _load_config(self) -> None:
-        url = (config_manager.get('torrent_client.url', '') or '').rstrip('/')
+        url = normalize_client_url(config_manager.get('torrent_client.url', ''))
         # Transmission's RPC endpoint is always /transmission/rpc — if the
         # user pasted a bare host URL, append it. If they pasted the full
         # /transmission/rpc URL, leave it.

core/watchlist_scanner.py

@@ -489,12 +489,16 @@ class WatchlistScanner:
         self._spotify_disabled_reason = reason
 
     def _spotify_available_for_run(self) -> bool:
-        """Check if Spotify should be used for this run."""
+        """Check if Spotify should be used for this run.
+
+        Available = real auth OR the no-creds SpotipyFree fallback (new-release
+        detection is metadata-only — get_artist_albums — so the free source can
+        serve it; the client routes internally when auth is missing/limited)."""
         if self._spotify_disabled_for_run:
             return False
         if not self.spotify_client:
             return False
-        return self.spotify_client.is_spotify_authenticated()
+        return self.spotify_client.is_spotify_metadata_available()
 
     def _spotify_is_primary_source(self) -> bool:
         """Check if Spotify is both authenticated and the configured primary metadata source.

core/worker_utils.py

@@ -1,10 +1,105 @@
 """Shared helpers for background workers."""
 
 import logging
+import re
 import threading
+from difflib import SequenceMatcher
+from typing import Optional
 
 logger = logging.getLogger(__name__)
 
+# Artist-match acceptance gate. Stricter than the 0.80 each worker uses for
+# album/track titles: artist names are short, so 0.80 lets distinct artists
+# slip through ("ODESZA"/"odessa", "Blance"/"Blanke", "Lady A"/"Lady Gaga" all
+# score 0.80-0.83). 0.85 rejects those while still tolerating real variation
+# that survives normalization.
+ARTIST_NAME_MATCH_THRESHOLD = 0.85
+
+# Whitelist of artist source-id columns we'll interpolate into SQL — guards the
+# conflict query against any unexpected column name.
+_ARTIST_ID_COLUMNS = frozenset({
+    'deezer_id', 'spotify_artist_id', 'itunes_artist_id', 'musicbrainz_id',
+    'discogs_id', 'audiodb_id', 'qobuz_id', 'tidal_id', 'amazon_id', 'soul_id',
+})
+
+
+def normalize_artist_name(name: str) -> str:
+    """Lowercase, drop ' - ...' suffixes / parentheticals / punctuation, and
+    collapse whitespace — the same normalization the per-worker matchers use."""
+    name = (name or '').lower().strip()
+    name = re.sub(r'\s+[-–—]\s+.*$', '', name)
+    name = re.sub(r'\s*\(.*?\)\s*', ' ', name)
+    name = re.sub(r'[^\w\s]', '', name)
+    name = re.sub(r'\s+', ' ', name).strip()
+    return name
+
+
+def artist_name_matches(query: str, result: str,
+                        threshold: float = ARTIST_NAME_MATCH_THRESHOLD) -> bool:
+    """True if two artist names match at/above ``threshold`` after normalization."""
+    nq, nr = normalize_artist_name(query), normalize_artist_name(result)
+    if not nq or not nr:
+        return False
+    return SequenceMatcher(None, nq, nr).ratio() >= threshold
+
+
+def _names_equivalent(a: str, b: str) -> bool:
+    return normalize_artist_name(a) == normalize_artist_name(b)
+
+
+def source_id_conflict(database, id_column: str, source_id, artist_id,
+                       artist_name: str) -> Optional[str]:
+    """Return the name of a DIFFERENTLY-named library artist that already holds
+    ``source_id`` in ``id_column``, or None.
+
+    A same-named holder (the same artist indexed on two media servers) is NOT a
+    conflict — both legitimately share the id. Only a different artist holding
+    the id signals the kind of corruption where one source id gets smeared
+    across unrelated artists.
+    """
+    if source_id in (None, ''):
+        return None
+    if id_column not in _ARTIST_ID_COLUMNS:
+        logger.debug(f"source_id_conflict: refusing unknown column {id_column!r}")
+        return None
+    try:
+        with database._get_connection() as conn:
+            rows = conn.execute(
+                f"SELECT name FROM artists WHERE {id_column} = ? AND id != ?",
+                (str(source_id), artist_id),
+            ).fetchall()
+    except Exception as e:
+        logger.debug(f"source_id_conflict check failed for {id_column}={source_id}: {e}")
+        return None
+    for (other_name,) in rows:
+        if not _names_equivalent(artist_name, other_name):
+            return other_name
+    return None
+
+
+def accept_artist_match(database, id_column: str, source_id, artist_id,
+                        query_name: str, result_name: str,
+                        threshold: float = ARTIST_NAME_MATCH_THRESHOLD) -> tuple:
+    """Decide whether to store ``source_id`` on an artist.
+
+    Returns ``(ok: bool, reason: str)``. Accepts only when the result's name
+    matches the library artist at/above ``threshold`` AND the id isn't already
+    claimed by a differently-named artist. ``reason`` explains a rejection (for
+    debug logging). This is the single gate every worker's artist match should
+    pass through, so the 'one id smeared across many artists' bug can't recur.
+    """
+    if not artist_name_matches(query_name, result_name, threshold):
+        return False, (
+            f"name mismatch '{query_name}' vs '{result_name}' (< {threshold})"
+        )
+    conflict = source_id_conflict(database, id_column, source_id, artist_id, query_name)
+    if conflict:
+        return False, (
+            f"{id_column}={source_id} already claimed by '{conflict}' — "
+            f"skipping to avoid a shared/duplicate id"
+        )
+    return True, ""
+
 
 def interruptible_sleep(stop_event: threading.Event, seconds: float, step: float = 0.5) -> bool:
     """Sleep in chunks so shutdown can interrupt long waits."""

database/music_database.py

@@ -790,6 +790,55 @@ class MusicDatabase:
             except Exception as e:
                 logger.debug("Failed to purge cached tracks/albums with junk artist names: %s", e)
 
+            # One-time migration: clear source ids that enrichment wrongly
+            # SHARED across differently-named artists. The album/track "artist
+            # id correction" path (Deezer/AudioDB/Qobuz/Tidal) used to overwrite
+            # an artist's source id from a match without a name check, so e.g.
+            # everyone featured on Kendrick Lamar's curated "Black Panther" album
+            # got stamped with Kendrick's Deezer id. The workers are now
+            # name-guarded so this can't recur; clearing the bad rows lets the
+            # next enrichment pass re-derive each artist's correct id.
+            # Same-name duplicates (one artist indexed on two media servers,
+            # legitimately sharing an id) are left alone via the DISTINCT-name
+            # check, so this only touches genuine corruption.
+            try:
+                cursor.execute("SELECT name FROM sqlite_master WHERE type='table' AND name='_source_id_dedupe_v1'")
+                if not cursor.fetchone():
+                    _dedupe_id_cols = [
+                        ('deezer_id', 'deezer_match_status'),
+                        ('spotify_artist_id', 'spotify_match_status'),
+                        ('itunes_artist_id', 'itunes_match_status'),
+                        ('musicbrainz_id', 'musicbrainz_match_status'),
+                        ('discogs_id', 'discogs_match_status'),
+                        ('audiodb_id', 'audiodb_match_status'),
+                        ('qobuz_id', 'qobuz_match_status'),
+                        ('tidal_id', 'tidal_match_status'),
+                    ]
+                    total_cleared = 0
+                    for id_col, status_col in _dedupe_id_cols:
+                        try:
+                            cursor.execute(f"""
+                                UPDATE artists
+                                SET {id_col} = NULL, {status_col} = NULL
+                                WHERE {id_col} IN (
+                                    SELECT {id_col} FROM artists
+                                    WHERE {id_col} IS NOT NULL AND {id_col} != ''
+                                    GROUP BY {id_col}
+                                    HAVING COUNT(DISTINCT LOWER(TRIM(name))) > 1
+                                )
+                            """)
+                            total_cleared += cursor.rowcount
+                        except Exception as col_err:
+                            logger.debug("Source-id dedupe skipped %s: %s", id_col, col_err)
+                    cursor.execute("CREATE TABLE _source_id_dedupe_v1 (applied_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP)")
+                    if total_cleared > 0:
+                        logger.info(
+                            f"Cleared {total_cleared} duplicated source ids shared across "
+                            f"differently-named artists — they'll re-derive on next enrichment"
+                        )
+            except Exception as e:
+                logger.debug("Failed to dedupe shared source ids: %s", e)
+
             # HiFi API instances table
             cursor.execute("""
                 CREATE TABLE IF NOT EXISTS hifi_instances (
@@ -970,6 +1019,10 @@ class MusicDatabase:
                 'canonical_album_id': 'TEXT DEFAULT NULL',
                 'canonical_score': 'REAL DEFAULT NULL',
                 'canonical_resolved_at': 'TIMESTAMP DEFAULT NULL',
+                # #758 — set when the user MANUALLY pins an album version. The
+                # auto resolve job (and any re-resolution) must never overwrite
+                # a locked pin, so a manual match stays put across cycles.
+                'canonical_locked': 'INTEGER DEFAULT 0',
             }
             for _col, _typedef in _canonical_cols.items():
                 if album_cols and _col not in album_cols:
@@ -978,17 +1031,27 @@ class MusicDatabase:
         except Exception as e:
             logger.error("Error repairing core media schema columns: %s", e)
 
-    def set_album_canonical(self, album_id, source: str, canonical_album_id: str, score: float) -> bool:
+    def set_album_canonical(self, album_id, source: str, canonical_album_id: str,
+                            score: float, locked: bool = False) -> bool:
         """Persist the resolved canonical (source, album_id, score) for an album
-        (#765 Stage 2). Returns True if a row was updated."""
+        (#765 Stage 2). Returns True if a row was updated.
+
+        ``locked=True`` marks a MANUAL pin (#758): the user explicitly chose this
+        album version. A manual write always wins (overwrites any existing pin).
+        An AUTO write (``locked=False``, the resolve job) will NOT overwrite a
+        locked pin — the guard is in the WHERE clause so it's atomic.
+        """
         conn = self._get_connection()
         try:
             cursor = conn.cursor()
+            # Auto writes can't clobber a manual lock; manual writes always apply.
+            guard = "" if locked else " AND (canonical_locked IS NULL OR canonical_locked = 0)"
             cursor.execute(
                 "UPDATE albums SET canonical_source = ?, canonical_album_id = ?, "
-                "canonical_score = ?, canonical_resolved_at = CURRENT_TIMESTAMP "
-                "WHERE id = ?",
-                (source, str(canonical_album_id), float(score), album_id),
+                "canonical_score = ?, canonical_locked = ?, "
+                "canonical_resolved_at = CURRENT_TIMESTAMP "
+                f"WHERE id = ?{guard}",
+                (source, str(canonical_album_id), float(score), 1 if locked else 0, album_id),
             )
             conn.commit()
             return cursor.rowcount > 0
@@ -999,15 +1062,16 @@ class MusicDatabase:
             conn.close()
 
     def get_album_canonical(self, album_id) -> Optional[dict]:
-        """Return ``{'source','album_id','score','resolved_at'}`` for an album's
-        pinned canonical release, or ``None`` when unresolved (#765 Stage 2).
-        Consumers treat ``None`` as 'fall back to today's behavior'."""
+        """Return ``{'source','album_id','score','resolved_at','locked'}`` for an
+        album's pinned canonical release, or ``None`` when unresolved (#765 Stage
+        2). ``locked`` is True for a manual pin (#758). Consumers treat ``None``
+        as 'fall back to today's behavior'."""
         conn = self._get_connection()
         try:
             cursor = conn.cursor()
             cursor.execute(
                 "SELECT canonical_source, canonical_album_id, canonical_score, "
-                "canonical_resolved_at FROM albums WHERE id = ?",
+                "canonical_resolved_at, canonical_locked FROM albums WHERE id = ?",
                 (album_id,),
             )
             row = cursor.fetchone()
@@ -1018,6 +1082,7 @@ class MusicDatabase:
                 'album_id': row[1],
                 'score': row[2],
                 'resolved_at': row[3],
+                'locked': bool(row[4]),
             }
         except Exception as e:
             logger.error("Error reading album canonical for %s: %s", album_id, e)
@@ -4621,21 +4686,29 @@ class MusicDatabase:
                     CREATE INDEX IF NOT EXISTS idx_mltm_lib_track
                     ON manual_library_track_matches (library_track_id)
                 """)
+                # Stable re-resolution key: a library rescan can drop/re-key
+                # tracks (esp. Jellyfin/Navidrome GUIDs), leaving library_track_id
+                # dangling. Storing the file path lets us re-find the current
+                # track id after a scan so manual matches survive it.
+                cursor.execute("PRAGMA table_info(manual_library_track_matches)")
+                _mltm_cols = {r[1] for r in cursor.fetchall()}
+                if 'library_file_path' not in _mltm_cols:
+                    cursor.execute("ALTER TABLE manual_library_track_matches ADD COLUMN library_file_path TEXT")
         except Exception as e:
             logger.error(f"Error creating manual_library_track_matches table: {e}")
 
     def save_manual_library_match(self, profile_id: int, source: str, source_track_id: str,
                                    library_track_id: str, **meta) -> bool:
         """Insert or replace a manual match. meta keys: source_title, source_artist,
-        source_album, source_context_json, server_source."""
+        source_album, source_context_json, server_source, library_file_path."""
         try:
             with self._get_connection() as conn:
                 conn.execute("""
                     INSERT INTO manual_library_track_matches
                         (profile_id, source, source_track_id, library_track_id,
                          source_title, source_artist, source_album,
-                         source_context_json, server_source, updated_at)
-                    VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, CURRENT_TIMESTAMP)
+                         source_context_json, server_source, library_file_path, updated_at)
+                    VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, CURRENT_TIMESTAMP)
                     ON CONFLICT(profile_id, source, source_track_id, server_source)
                     DO UPDATE SET
                         library_track_id = excluded.library_track_id,
@@ -4643,18 +4716,46 @@ class MusicDatabase:
                         source_artist = excluded.source_artist,
                         source_album = excluded.source_album,
                         source_context_json = excluded.source_context_json,
+                        library_file_path = excluded.library_file_path,
                         updated_at = CURRENT_TIMESTAMP
                 """, (
                     profile_id, source, source_track_id, library_track_id,
                     meta.get('source_title'), meta.get('source_artist'),
                     meta.get('source_album'), meta.get('source_context_json'),
-                    meta.get('server_source', ''),
+                    meta.get('server_source', ''), meta.get('library_file_path'),
                 ))
                 return True
         except Exception as e:
             logger.error(f"save_manual_library_match error: {e}")
             return False
 
+    def find_track_id_by_file_path(self, file_path: str) -> Optional[str]:
+        """Return the current tracks.id for a file path, or None.
+
+        Used to re-resolve a manual match whose stored library_track_id went
+        stale after a rescan re-keyed the track. Exact path first, then a
+        basename fallback (handles server-vs-local path differences)."""
+        if not file_path:
+            return None
+        try:
+            conn = self._get_connection()
+            cursor = conn.cursor()
+            cursor.execute("SELECT id FROM tracks WHERE file_path = ? LIMIT 1", (file_path,))
+            row = cursor.fetchone()
+            if row:
+                return str(row[0])
+            import os as _os
+            fname = _os.path.basename(str(file_path).replace('\\', '/'))
+            if fname:
+                cursor.execute("SELECT id FROM tracks WHERE file_path LIKE ? LIMIT 1", (f"%{fname}",))
+                row = cursor.fetchone()
+                if row:
+                    return str(row[0])
+            return None
+        except Exception as e:
+            logger.error(f"find_track_id_by_file_path error: {e}")
+            return None
+
     def get_manual_library_match(self, profile_id: int, source: str,
                                   source_track_id: str, server_source: str = '') -> Optional[Dict[str, Any]]:
         """Return match row dict or None."""
@@ -5948,8 +6049,12 @@ class MusicDatabase:
                     except Exception as e:
                         logger.debug("history logging: %s", e)
 
-                return True
-                
+                # Truthy on success (existing `if track_success` callers keep
+                # working); the specific value lets the scan worker tell a
+                # genuinely new row from an updated one so it can reconcile
+                # embedded IDs only for new arrivals.
+                return 'inserted' if is_new_track else 'updated'
+
             except Exception as e:
                 error_text = str(e).lower()
                 if (

scripts/dedupe_source_ids.py

@@ -0,0 +1,59 @@
+#!/usr/bin/env python3
+"""One-off repair for source ids that enrichment wrongly shared across multiple
+artists (the Kendrick/Jorja corruption — one Deezer/AudioDB/Qobuz/Tidal id
+stamped onto several unrelated artists).
+
+Dry-run by default — shows exactly what it would clear and writes nothing.
+
+Usage:
+    python scripts/dedupe_source_ids.py            # dry-run (review first)
+    python scripts/dedupe_source_ids.py --apply    # actually clear them
+
+After --apply, run metadata enrichment so the (now name-checked) workers
+re-derive each artist's id correctly. Stop the app first so the DB isn't locked.
+"""
+
+import logging
+import os
+import sys
+
+# Allow running directly (`python scripts/dedupe_source_ids.py`) — put the repo
+# root on the path so `core` / `database` import.
+sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+
+from core.maintenance.dedupe_source_ids import clear_corrupt_source_ids  # noqa: E402
+from database.music_database import MusicDatabase  # noqa: E402
+
+if not logging.getLogger().handlers:
+    logging.basicConfig(level=logging.INFO, format="%(message)s")
+logger = logging.getLogger("dedupe_source_ids")
+
+
+def main():
+    apply = "--apply" in sys.argv[1:]
+    db = MusicDatabase()
+    report = clear_corrupt_source_ids(db, dry_run=not apply)
+
+    mode = "APPLYING" if apply else "DRY-RUN (no changes written)"
+    logger.info(f"=== Source-id corruption repair — {mode} ===")
+    logger.info(
+        f"Corrupt clusters: {report['cluster_count']}  |  "
+        f"artists affected: {report['artist_count']}"
+    )
+    if report['by_source']:
+        logger.info("By source: " + ", ".join(
+            f"{s}={n}" for s, n in sorted(report['by_source'].items())
+        ))
+    for c in report['clusters']:
+        logger.info(f"  [{c['source']}] id {c['source_id']} -> {', '.join(c['artists'])}")
+
+    if not report['cluster_count']:
+        logger.info("Nothing to clean — no shared source ids across differently-named artists.")
+    elif apply:
+        logger.info("Cleared. Now run metadata enrichment to re-derive these ids correctly.")
+    else:
+        logger.info("Re-run with --apply to clear these (then run enrichment to re-derive).")
+
+
+if __name__ == "__main__":
+    main()

services/sync_service.py

@@ -195,6 +195,26 @@ class PlaylistSyncService:
                 failed_tracks=failed_tracks
             ))
     
+    def _reconcile_or_replace(self, client, playlist_name: str, tracks) -> bool:
+        """Reconcile mode (#792): edit the playlist in place (add/remove delta,
+        preserving its image + description + identity). If the client lacks
+        reconcile or it fails, fall back to the destructive replace so the sync
+        still succeeds — logged loudly so a failing in-place edit is diagnosable.
+        """
+        fn = getattr(client, 'reconcile_playlist', None)
+        if fn is None:
+            return client.update_playlist(playlist_name, tracks)
+        try:
+            if fn(playlist_name, tracks):
+                return True
+            logger.warning(
+                "Reconcile sync failed for '%s' — falling back to replace "
+                "(playlist will be recreated this once)", playlist_name)
+        except Exception as e:
+            logger.warning(
+                "Reconcile sync errored for '%s' (%s) — falling back to replace", playlist_name, e)
+        return client.update_playlist(playlist_name, tracks)
+
     async def sync_playlist(self, playlist: SpotifyPlaylist, download_missing: bool = False, profile_id: int = None, sync_mode: str = 'replace') -> SyncResult:
         self._active_profile_id = profile_id
         # Check if THIS specific playlist is already syncing
@@ -378,6 +398,8 @@ class PlaylistSyncService:
                     )
                     if sync_mode == 'append':
                         sync_success = media_client.append_to_playlist(playlist.name, valid_tracks)
+                    elif sync_mode == 'reconcile':
+                        sync_success = self._reconcile_or_replace(media_client, playlist.name, valid_tracks)
                     else:
                         sync_success = media_client.update_playlist(playlist.name, valid_tracks)
 

tests/discovery/test_discovery_playlist.py

@@ -496,3 +496,45 @@ def test_multi_playlist_aggregates_grand_total():
 
     # All 3 tracks discovered → 3 extra_data writes
     assert len(deps._db.extra_data_writes) == 3
+
+
+# ---------------------------------------------------------------------------
+# _canonical_best_score — #785: file/CSV playlists keep raw "Artist - Title"
+# titles (YouTube is cleaned at ingest); the worker must try the canonical form.
+# ---------------------------------------------------------------------------
+
+from types import SimpleNamespace  # noqa: E402
+
+
+def test_canonical_best_score_matches_file_style_title():
+    # Raw "Artist - Title" scores low; canonical "Title" scores high → take it.
+    def score(title, artist, dur, results):
+        if title == 'Do I Wanna Know?':
+            return ('MATCH', 0.95, None)
+        return (None, 0.2, None)
+    deps = SimpleNamespace(discovery_score_candidates=score)
+    match, conf = dp._canonical_best_score(
+        deps, 'Arctic Monkeys - Do I Wanna Know?', 'Arctic Monkeys', 0, ['r'])
+    assert match == 'MATCH'
+    assert conf == 0.95
+
+
+def test_canonical_best_score_clean_title_scored_once():
+    calls = []
+    def score(title, artist, dur, results):
+        calls.append(title)
+        return ('M', 0.9, None)
+    deps = SimpleNamespace(discovery_score_candidates=score)
+    match, conf = dp._canonical_best_score(deps, 'Do I Wanna Know?', 'Arctic Monkeys', 0, ['r'])
+    assert (match, conf) == ('M', 0.9)
+    assert calls == ['Do I Wanna Know?']  # canonical == original → no second score
+
+
+def test_canonical_best_score_keeps_original_when_better():
+    # Best-of: if the raw title actually scores higher, keep it.
+    def score(title, artist, dur, results):
+        return ('CANON', 0.6, None) if title == 'Do I Wanna Know?' else ('ORIG', 0.9, None)
+    deps = SimpleNamespace(discovery_score_candidates=score)
+    match, conf = dp._canonical_best_score(
+        deps, 'Arctic Monkeys - Do I Wanna Know?', 'Arctic Monkeys', 0, ['r'])
+    assert (match, conf) == ('ORIG', 0.9)

tests/discovery/test_manual_match.py

@@ -10,6 +10,7 @@ AST-parsing the route file).
 from core.discovery.manual_match import (
     derive_manual_match_provider,
     is_drifted_for_redo,
+    should_rediscover,
 )
 
 
@@ -104,3 +105,149 @@ def test_drift_default_provider_is_spotify_when_absent():
     extra = {'discovered': True}  # no provider field
     assert is_drifted_for_redo(extra, 'spotify') is False
     assert is_drifted_for_redo(extra, 'musicbrainz') is True
+
+
+# ---------------------------------------------------------------------------
+# should_rediscover — the Playlist Pipeline pre-scan gate
+# ---------------------------------------------------------------------------
+
+
+def test_rediscovers_never_discovered_track():
+    assert should_rediscover({}) is True
+    assert should_rediscover(None) is True
+
+
+def test_skips_complete_discovery():
+    extra = {
+        'discovered': True,
+        'matched_data': {'track_number': 3, 'album': {'release_date': '2020'}},
+    }
+    assert should_rediscover(extra) is False
+
+
+def test_rediscovers_incomplete_discovery():
+    # Missing track_number / release_date / album.id — re-discover to backfill.
+    extra = {'discovered': True, 'matched_data': {'name': 'X'}}
+    assert should_rediscover(extra) is True
+
+
+def test_album_id_satisfies_completeness():
+    extra = {
+        'discovered': True,
+        'matched_data': {'track_number': 1, 'album': {'id': 'al-1'}},
+    }
+    assert should_rediscover(extra) is False
+
+
+def test_rediscovers_wing_it_stub():
+    extra = {'discovered': True, 'wing_it_fallback': True}
+    assert should_rediscover(extra) is True
+
+
+def test_skips_manual_match():
+    extra = {'discovered': True, 'manual_match': True}
+    assert should_rediscover(extra) is False
+
+
+def test_skips_unmatched_by_user():
+    extra = {'unmatched_by_user': True}
+    assert should_rediscover(extra) is False
+
+
+def test_regression_manual_match_wins_over_stale_wing_it_flag():
+    """The #799 revert bug: extra_data is MERGED on save, so a track fixed
+    after being a Wing It stub still carries wing_it_fallback=True alongside
+    the new manual_match=True. The manual match MUST win — otherwise the
+    pipeline re-discovers and silently reverts the user's pick to Wing It.
+
+    Before the fix the pre-scan checked wing_it_fallback first and returned
+    True (re-discover). It must now skip."""
+    extra = {
+        'discovered': True,
+        'wing_it_fallback': True,   # stale flag left by the merge
+        'manual_match': True,       # the user's authoritative fix
+        'matched_data': {'name': 'The Real Match'},
+    }
+    assert should_rediscover(extra) is False
+
+
+def test_manual_match_wins_even_without_other_fields():
+    # Lean Fix-popup save shape (no track_number/album) must still be honored.
+    extra = {'discovered': True, 'manual_match': True, 'wing_it_fallback': True}
+    assert should_rediscover(extra) is False
+
+
+# ---------------------------------------------------------------------------
+# Equivalence guard: should_rediscover must match the ORIGINAL inline pre-scan
+# logic for EVERY flag combination except the one intended fix (manual_match
+# beating a stale wing_it_fallback). This pins that the auto Playlist Pipeline
+# behaves identically post-refactor — no regression.
+# ---------------------------------------------------------------------------
+
+import itertools
+
+
+def _original_pre_scan(extra):
+    """Verbatim reproduction of the pre-refactor playlist.py branch logic.
+    Returns True = re-discover (undiscovered_tracks), False = skip."""
+    if extra.get('discovered'):
+        if extra.get('wing_it_fallback'):
+            return True
+        elif extra.get('manual_match'):
+            return False
+        else:
+            md = extra.get('matched_data', {})
+            album = md.get('album', {})
+            has_track_num = md.get('track_number')
+            has_release = album.get('release_date') if isinstance(album, dict) else None
+            has_album_id = album.get('id') if isinstance(album, dict) else None
+            if has_track_num and (has_release or has_album_id):
+                return False
+            else:
+                return True
+    elif extra.get('unmatched_by_user'):
+        return False
+    else:
+        return True
+
+
+_MATCHED_VARIANTS = {
+    'absent': None,  # key omitted
+    'complete': {'track_number': 1, 'album': {'release_date': '2020'}},
+    'incomplete': {'name': 'x'},
+}
+
+
+def test_should_rediscover_matches_original_logic_for_all_combinations():
+    bools = [True, False]
+    diverged = 0
+    for discovered, wing, manual, unmatched, md_key in itertools.product(
+        bools, bools, bools, bools, _MATCHED_VARIANTS
+    ):
+        extra = {}
+        if discovered:
+            extra['discovered'] = True
+        if wing:
+            extra['wing_it_fallback'] = True
+        if manual:
+            extra['manual_match'] = True
+        if unmatched:
+            extra['unmatched_by_user'] = True
+        if _MATCHED_VARIANTS[md_key] is not None:
+            extra['matched_data'] = _MATCHED_VARIANTS[md_key]
+
+        new = should_rediscover(extra)
+        old = _original_pre_scan(extra)
+
+        # The single intended divergence: a discovered track carrying BOTH a
+        # stale wing_it_fallback AND a manual_match. Old re-discovered (the
+        # bug); new skips (manual is authoritative).
+        is_intended_fix = discovered and wing and manual
+        if is_intended_fix:
+            assert old is True and new is False, (extra, old, new)
+            diverged += 1
+        else:
+            assert new == old, (extra, new, old)
+
+    # Sanity: the fix actually triggered on the expected subset.
+    assert diverged > 0

tests/downloads/test_downloads_candidates.py

@@ -461,6 +461,45 @@ def test_auto_search_pick_does_not_inject_acoustid_bypass():
     assert "_user_manual_pick" not in ctx
 
 
+def test_skip_acoustid_track_flag_injects_bypass():
+    """Issue #797: when the album-download request had the per-request
+    'Skip AcoustID verification' toggle on, the master worker stamps
+    `_skip_acoustid=True` onto each track's track_info. The candidates
+    helper must propagate that into the post-process context as
+    `_skip_quarantine_check='acoustid'` so AcoustID never quarantines
+    this request's files (e.g. correct downloads of non-English artists
+    whose native-script metadata AcoustID can't reconcile)."""
+    deps = _build_deps()
+    _seed_task("t_skip_aid", track_info={"_skip_acoustid": True})
+
+    candidates = [_Candidate(filename="skip.flac", confidence=0.99)]
+    track = _Track()
+
+    result = dc.attempt_download_with_candidates("t_skip_aid", candidates, track, batch_id="b1", deps=deps)
+
+    assert result is True
+    ctx = matched_downloads_context["user1::skip.flac"]
+    assert ctx["_skip_quarantine_check"] == "acoustid"
+    # It's the toggle path, NOT a manual pick.
+    assert "_user_manual_pick" not in ctx
+
+
+def test_no_skip_acoustid_flag_keeps_verification():
+    """Without the toggle (no `_skip_acoustid` on track_info), AcoustID
+    verification must still run — the bypass is opt-in per request."""
+    deps = _build_deps()
+    _seed_task("t_no_skip_aid", track_info={})  # no _skip_acoustid
+
+    candidates = [_Candidate(filename="verify.flac", confidence=0.99)]
+    track = _Track()
+
+    result = dc.attempt_download_with_candidates("t_no_skip_aid", candidates, track, batch_id="b1", deps=deps)
+
+    assert result is True
+    ctx = matched_downloads_context["user1::verify.flac"]
+    assert "_skip_quarantine_check" not in ctx
+
+
 def test_equal_confidence_candidates_prefer_better_peer_quality():
     """Equal-confidence Soulseek candidates use peer quality as the tiebreaker."""
     deps = _build_deps()

tests/imports/test_import_pipeline.py

@@ -209,7 +209,6 @@ def test_post_process_matched_download_forwards_separate_metadata_runtime(tmp_pa
 
     monkeypatch.setattr(import_pipeline, "record_soulsync_library_entry", _record_library)
     monkeypatch.setattr(import_pipeline, "check_and_remove_from_wishlist", lambda *args, **kwargs: None)
-    monkeypatch.setattr(import_pipeline, "record_retag_download", lambda *args, **kwargs: None)
 
     context = {
         "track_info": {"_playlist_folder_mode": True, "_playlist_name": "Playlist"},

tests/library/test_embedded_id_reconcile.py

@@ -0,0 +1,363 @@
+"""Tests for core/library/embedded_id_reconcile.py.
+
+The reconcile job reads provider IDs already embedded in a file's tags
+(by SoulSync or MusicBrainz Picard) and gap-fills them into the library
+DB so enrichment workers skip the API call. These pin the guarantees that
+make it safe to run across a whole library while workers run concurrently:
+
+  1. gap-fill only — an existing id is NEVER overwritten,
+  2. disagreements are reported as conflicts, not applied,
+  3. the write is ATOMICALLY guarded — if a worker fills the column
+     between plan and apply, the apply no-ops (no clobber).
+"""
+
+from __future__ import annotations
+
+import sqlite3
+
+from core.library.embedded_id_reconcile import (
+    Fill,
+    ReconcileApplied,
+    ReconcilePlan,
+    ReconcileTotals,
+    apply_reconcile_plan,
+    plan_reconcile,
+    reconcile_library,
+    reconcile_track_row,
+)
+
+
+# ---------------------------------------------------------------------------
+# plan_reconcile — the pure planning layer
+# ---------------------------------------------------------------------------
+
+def test_empty_inputs_yield_empty_plan():
+    plan = plan_reconcile(None, None)
+    assert isinstance(plan, ReconcilePlan)
+    assert plan.has_updates is False
+    assert plan.filled == 0
+    assert plan.conflicts == []
+
+
+def test_fills_all_three_entities_from_one_file():
+    tags = {'spotify_track_id': 'TRK', 'spotify_album_id': 'ALB', 'spotify_artist_id': 'ART'}
+    plan = plan_reconcile(tags, {'track': {}, 'album': {}, 'artist': {}})
+
+    assert plan.filled == 3
+    by_entity = {(f.entity, f.id_column): f.value for f in plan.fills}
+    assert by_entity[('track', 'spotify_track_id')] == 'TRK'
+    assert by_entity[('album', 'spotify_album_id')] == 'ALB'
+    assert by_entity[('artist', 'spotify_artist_id')] == 'ART'
+    # status column pairing is carried on each Fill
+    track_fill = plan.fills_for('track')[0]
+    assert track_fill.status_column == 'spotify_match_status'
+
+
+def test_never_overwrites_an_existing_id():
+    plan = plan_reconcile({'spotify_artist_id': 'NEW'},
+                          {'artist': {'spotify_artist_id': 'EXISTING'}})
+    assert plan.filled == 0
+    assert plan.fills_for('artist') == []
+    assert len(plan.conflicts) == 1
+    c = plan.conflicts[0]
+    assert c['existing'] == 'EXISTING' and c['embedded'] == 'NEW' and c['entity'] == 'artist'
+
+
+def test_matching_existing_id_is_noop_not_conflict():
+    plan = plan_reconcile({'spotify_artist_id': 'SAME'},
+                          {'artist': {'spotify_artist_id': 'SAME'}})
+    assert plan.filled == 0
+    assert plan.conflicts == []
+    assert plan.already_present == 1
+
+
+def test_blank_and_whitespace_values_ignored():
+    tags = {'spotify_artist_id': '   ', 'spotify_album_id': '', 'itunes_track_id': None}
+    plan = plan_reconcile(tags, {'track': {}, 'album': {}, 'artist': {}})
+    assert plan.has_updates is False
+
+
+def test_whitespace_padded_embedded_id_is_trimmed_and_filled():
+    plan = plan_reconcile({'spotify_track_id': '  TRK  '}, {'track': {}})
+    assert plan.fills_for('track')[0].value == 'TRK'
+
+
+def test_single_column_provider_maps_per_entity():
+    # Deezer/Tidal/AudioDB reuse one id column across entity types; fills
+    # must be keyed by entity so they don't collide.
+    tags = {'deezer_track_id': 'DT', 'deezer_album_id': 'DA', 'deezer_artist_id': 'DR'}
+    plan = plan_reconcile(tags, {'track': {}, 'album': {}, 'artist': {}})
+    vals = {f.entity: f.value for f in plan.fills}
+    assert vals == {'track': 'DT', 'album': 'DA', 'artist': 'DR'}
+    assert plan.filled == 3
+
+
+def test_mb_album_and_artist_filled_track_recording_skipped():
+    tags = {'musicbrainz_albumid': 'MBA', 'musicbrainz_artistid': 'MBR', 'musicbrainz_trackid': 'MBT'}
+    plan = plan_reconcile(tags, {'track': {}, 'album': {}, 'artist': {}})
+    cols = {(f.entity, f.id_column): f.value for f in plan.fills}
+    assert cols[('album', 'musicbrainz_release_id')] == 'MBA'
+    assert cols[('artist', 'musicbrainz_id')] == 'MBR'
+    assert plan.fills_for('track') == []  # recording id not reconciled
+
+
+def test_lastfm_url_maps_to_track_only():
+    # The file carries a single LASTFM_URL = the TRACK's last.fm url. It must
+    # fill tracks.lastfm_url and NOT be smeared onto album/artist (whose
+    # last.fm urls are different urls entirely).
+    plan = plan_reconcile({'lastfm_url': 'https://last.fm/music/A/_/Song'},
+                          {'track': {}, 'album': {}, 'artist': {}})
+    assert plan.filled == 1
+    f = plan.fills_for('track')[0]
+    assert f.id_column == 'lastfm_url' and f.status_column == 'lastfm_match_status'
+    assert plan.fills_for('album') == [] and plan.fills_for('artist') == []
+
+
+def test_partial_fill_when_one_entity_already_matched():
+    tags = {'spotify_artist_id': 'ART', 'spotify_album_id': 'ALB'}
+    current = {'artist': {'spotify_artist_id': 'ART'}, 'album': {}}
+    plan = plan_reconcile(tags, current)
+    assert plan.filled == 1
+    assert plan.fills_for('album')[0].value == 'ALB'
+    assert plan.fills_for('artist') == []
+    assert plan.already_present == 1
+
+
+# ---------------------------------------------------------------------------
+# apply_reconcile_plan — the DB layer (in-memory sqlite)
+# ---------------------------------------------------------------------------
+
+def _make_db():
+    conn = sqlite3.connect(':memory:')
+    cur = conn.cursor()
+    for table, idcol in (('tracks', 'spotify_track_id'), ('albums', 'spotify_album_id'),
+                         ('artists', 'spotify_artist_id')):
+        cur.execute(f"""CREATE TABLE {table} (id TEXT PRIMARY KEY, {idcol} TEXT,
+            spotify_match_status TEXT, spotify_last_attempted TIMESTAMP)""")
+    cur.execute("INSERT INTO tracks (id) VALUES ('t1')")
+    cur.execute("INSERT INTO albums (id) VALUES ('al1')")
+    cur.execute("INSERT INTO artists (id) VALUES ('ar1')")
+    conn.commit()
+    return conn, cur
+
+
+def test_apply_writes_ids_status_and_timestamp():
+    conn, cur = _make_db()
+    plan = plan_reconcile(
+        {'spotify_track_id': 'TRK', 'spotify_album_id': 'ALB', 'spotify_artist_id': 'ART'},
+        {'track': {}, 'album': {}, 'artist': {}},
+    )
+    applied = apply_reconcile_plan(cur, {'track': 't1', 'album': 'al1', 'artist': 'ar1'}, plan)
+    conn.commit()
+    assert isinstance(applied, ReconcileApplied)
+    assert applied.rows_updated == 3 and applied.ids_filled == 3
+
+    cur.execute("SELECT spotify_track_id, spotify_match_status, spotify_last_attempted FROM tracks WHERE id='t1'")
+    tid, status, attempted = cur.fetchone()
+    assert tid == 'TRK' and status == 'matched' and attempted is not None
+
+
+def test_apply_guard_blocks_overwrite_under_concurrency():
+    # THE headline hardening: a worker fills the column AFTER we planned
+    # (plan saw empty) but BEFORE we apply. The guarded UPDATE must no-op
+    # and leave the worker's value intact.
+    conn, cur = _make_db()
+    plan = plan_reconcile({'spotify_artist_id': 'FROM_FILE'}, {'artist': {}})  # planned: empty
+    # Simulate a concurrent enrichment worker matching it in the meantime.
+    cur.execute("UPDATE artists SET spotify_artist_id='FROM_WORKER', spotify_match_status='matched' WHERE id='ar1'")
+    conn.commit()
+
+    applied = apply_reconcile_plan(cur, {'artist': 'ar1'}, plan)
+    conn.commit()
+    assert applied.ids_filled == 0 and applied.rows_updated == 0  # guard blocked it
+
+    cur.execute("SELECT spotify_artist_id FROM artists WHERE id='ar1'")
+    assert cur.fetchone()[0] == 'FROM_WORKER'  # worker's value preserved
+
+
+def test_apply_guard_treats_empty_string_as_fillable():
+    conn, cur = _make_db()
+    cur.execute("UPDATE artists SET spotify_artist_id='' WHERE id='ar1'")  # empty string, not NULL
+    conn.commit()
+    plan = plan_reconcile({'spotify_artist_id': 'ART'}, {'artist': {}})
+    applied = apply_reconcile_plan(cur, {'artist': 'ar1'}, plan)
+    conn.commit()
+    assert applied.ids_filled == 1
+    cur.execute("SELECT spotify_artist_id FROM artists WHERE id='ar1'")
+    assert cur.fetchone()[0] == 'ART'
+
+
+def test_apply_skips_unknown_columns_without_erroring():
+    # Schema missing a provider's columns must not raise — the plan targets
+    # tidal_id which this minimal schema lacks; it's silently skipped.
+    conn, cur = _make_db()
+    plan = plan_reconcile({'tidal_artist_id': 'TID', 'spotify_artist_id': 'ART'},
+                          {'track': {}, 'album': {}, 'artist': {}})
+    applied = apply_reconcile_plan(cur, {'artist': 'ar1'}, plan)
+    conn.commit()
+    cur.execute("SELECT spotify_artist_id FROM artists WHERE id='ar1'")
+    assert cur.fetchone()[0] == 'ART'
+    assert applied.ids_filled == 1  # only the existing spotify column landed
+
+
+def test_apply_skips_entity_with_no_id():
+    conn, cur = _make_db()
+    plan = plan_reconcile({'spotify_album_id': 'ALB'}, {'album': {}})
+    applied = apply_reconcile_plan(cur, {'track': 't1'}, plan)  # no album id supplied
+    assert applied.rows_updated == 0 and applied.ids_filled == 0
+
+
+def test_apply_empty_plan_is_noop():
+    conn, cur = _make_db()
+    applied = apply_reconcile_plan(cur, {'track': 't1'}, ReconcilePlan())
+    assert applied.rows_updated == 0 and applied.ids_filled == 0
+
+
+# ---------------------------------------------------------------------------
+# reconcile_track_row — the per-track orchestration (id extraction, plan→apply,
+# sibling-map freshening)
+# ---------------------------------------------------------------------------
+
+def test_reconcile_track_row_unreadable_file_is_noop():
+    conn, cur = _make_db()
+    result = reconcile_track_row(cur, {'id': 't1'}, {}, {}, None)
+    assert result.readable is False
+    assert result.applied.ids_filled == 0
+
+
+def test_reconcile_track_row_fills_track_and_parents():
+    conn, cur = _make_db()
+    track_row = {'id': 't1', 'album_id': 'al1', 'artist_id': 'ar1'}
+    album_map = {'al1': {}}
+    artist_map = {'ar1': {}}
+    tags = {'spotify_track_id': 'TRK', 'spotify_album_id': 'ALB', 'spotify_artist_id': 'ART'}
+    result = reconcile_track_row(cur, track_row, album_map, artist_map, tags)
+    conn.commit()
+    assert result.readable is True
+    assert result.applied.ids_filled == 3 and result.applied.rows_updated == 3
+    # parent maps were freshened in place
+    assert album_map['al1']['spotify_album_id'] == 'ALB'
+    assert artist_map['ar1']['spotify_artist_id'] == 'ART'
+
+
+def test_reconcile_sibling_tracks_dont_refill_shared_parent():
+    # Two tracks on the same album/artist. The first fills the album+artist
+    # ids; the second must see them already present (via the freshened map)
+    # and NOT re-apply — proving the map keeps siblings from redundant work.
+    conn, cur = _make_db()
+    cur.execute("INSERT INTO tracks (id) VALUES ('t2')")
+    conn.commit()
+    album_map = {'al1': {}}
+    artist_map = {'ar1': {}}
+    tags = {'spotify_album_id': 'ALB', 'spotify_artist_id': 'ART', 'spotify_track_id': 'T1'}
+
+    r1 = reconcile_track_row(cur, {'id': 't1', 'album_id': 'al1', 'artist_id': 'ar1'},
+                             album_map, artist_map, tags)
+    # Second track: same album/artist ids embedded, its own track id.
+    tags2 = {'spotify_album_id': 'ALB', 'spotify_artist_id': 'ART', 'spotify_track_id': 'T2'}
+    r2 = reconcile_track_row(cur, {'id': 't2', 'album_id': 'al1', 'artist_id': 'ar1'},
+                             album_map, artist_map, tags2)
+    conn.commit()
+
+    assert r1.applied.ids_filled == 3            # track + album + artist
+    assert r2.applied.ids_filled == 1            # only t2's own track id; parents already filled
+    assert r2.conflicts == 0
+
+
+def test_reconcile_track_row_handles_null_parent_ids():
+    conn, cur = _make_db()
+    # Track with no album/artist linkage — only its own id should fill.
+    result = reconcile_track_row(cur, {'id': 't1', 'album_id': None, 'artist_id': None},
+                                 {}, {}, {'spotify_track_id': 'TRK', 'spotify_album_id': 'ALB'})
+    conn.commit()
+    assert result.applied.ids_filled == 1  # album fill has no album id to land on
+    cur.execute("SELECT spotify_track_id FROM tracks WHERE id='t1'")
+    assert cur.fetchone()[0] == 'TRK'
+
+
+# ---------------------------------------------------------------------------
+# reconcile_library — the shared orchestration (paging, lazy maps, scope)
+# ---------------------------------------------------------------------------
+
+def _make_library_db():
+    conn = sqlite3.connect(':memory:')
+    conn.row_factory = sqlite3.Row
+    cur = conn.cursor()
+    cur.execute("""CREATE TABLE tracks (id TEXT PRIMARY KEY, album_id TEXT, artist_id TEXT,
+        file_path TEXT, title TEXT, spotify_track_id TEXT, spotify_match_status TEXT,
+        spotify_last_attempted TIMESTAMP)""")
+    cur.execute("""CREATE TABLE albums (id TEXT PRIMARY KEY, spotify_album_id TEXT,
+        spotify_match_status TEXT, spotify_last_attempted TIMESTAMP)""")
+    cur.execute("""CREATE TABLE artists (id TEXT PRIMARY KEY, spotify_artist_id TEXT,
+        spotify_match_status TEXT, spotify_last_attempted TIMESTAMP)""")
+    # Two tracks on the same album/artist, one orphan track with no file.
+    cur.execute("INSERT INTO artists (id) VALUES ('ar1')")
+    cur.execute("INSERT INTO albums (id) VALUES ('al1')")
+    cur.execute("INSERT INTO tracks (id, album_id, artist_id, file_path, title) VALUES ('t1','al1','ar1','/a.flac','A')")
+    cur.execute("INSERT INTO tracks (id, album_id, artist_id, file_path, title) VALUES ('t2','al1','ar1','/b.flac','B')")
+    cur.execute("INSERT INTO tracks (id, album_id, artist_id, file_path, title) VALUES ('t3','al1','ar1','','NoFile')")
+    conn.commit()
+    return conn, cur
+
+
+def _reader(mapping):
+    """read_tags stub: file_path -> tags dict (or None)."""
+    return lambda fp: mapping.get(fp)
+
+
+def test_reconcile_library_whole_library_fills_all():
+    conn, cur = _make_library_db()
+    tags = {
+        '/a.flac': {'spotify_track_id': 'TA', 'spotify_album_id': 'ALB', 'spotify_artist_id': 'ART'},
+        '/b.flac': {'spotify_track_id': 'TB', 'spotify_album_id': 'ALB', 'spotify_artist_id': 'ART'},
+    }
+    totals = reconcile_library(conn, _reader(tags))
+    assert isinstance(totals, ReconcileTotals)
+    # t3 has empty file_path -> excluded from the whole-library SELECT entirely.
+    assert totals.total == 2 and totals.processed == 2
+    # t1: track+album+artist (3); t2: only its own track id (parents already filled) (1)
+    assert totals.ids_filled == 4
+    cur.execute("SELECT spotify_track_id FROM tracks WHERE id='t2'")
+    assert cur.fetchone()[0] == 'TB'
+    cur.execute("SELECT spotify_album_id FROM albums WHERE id='al1'")
+    assert cur.fetchone()[0] == 'ALB'
+
+
+def test_reconcile_library_scoped_to_given_ids():
+    conn, cur = _make_library_db()
+    tags = {'/b.flac': {'spotify_track_id': 'TB'}, '/a.flac': {'spotify_track_id': 'TA'}}
+    totals = reconcile_library(conn, _reader(tags), track_ids=['t2'])
+    assert totals.total == 1 and totals.ids_filled == 1
+    cur.execute("SELECT spotify_track_id FROM tracks WHERE id='t2'")
+    assert cur.fetchone()[0] == 'TB'
+    cur.execute("SELECT spotify_track_id FROM tracks WHERE id='t1'")
+    assert cur.fetchone()[0] is None  # not in scope
+
+
+def test_reconcile_library_unreadable_counted():
+    conn, cur = _make_library_db()
+    totals = reconcile_library(conn, _reader({}), track_ids=['t1', 't2'])  # reader returns None
+    assert totals.unreadable == 2 and totals.ids_filled == 0
+
+
+def test_reconcile_library_is_idempotent():
+    conn, cur = _make_library_db()
+    tags = {'/a.flac': {'spotify_track_id': 'TA', 'spotify_album_id': 'ALB', 'spotify_artist_id': 'ART'}}
+    first = reconcile_library(conn, _reader(tags), track_ids=['t1'])
+    second = reconcile_library(conn, _reader(tags), track_ids=['t1'])
+    assert first.ids_filled == 3
+    assert second.ids_filled == 0  # nothing left to fill
+
+
+def test_reconcile_library_progress_and_stop():
+    conn, cur = _make_library_db()
+    seen = []
+    reconcile_library(conn, _reader({'/a.flac': {'spotify_track_id': 'TA'}}),
+                      track_ids=['t1', 't2'],
+                      on_progress=lambda totals, title: seen.append(title))
+    assert seen == ['A', 'B']
+
+    # should_stop halts before processing anything
+    totals = reconcile_library(conn, _reader({}), track_ids=['t1', 't2'],
+                               should_stop=lambda: True)
+    assert totals.processed == 0

tests/library/test_retag.py

@@ -1,321 +0,0 @@
-"""Tests for core/library/retag.py — retag worker."""
-
-from __future__ import annotations
-
-import threading
-from dataclasses import dataclass
-
-import pytest
-
-from core.library import retag as ret
-
-
-# ---------------------------------------------------------------------------
-# Fakes
-# ---------------------------------------------------------------------------
-
-class _FakeSpotify:
-    def __init__(self, album=None, tracks=None):
-        self._album = album
-        self._tracks = tracks
-
-    def get_album(self, album_id):
-        return self._album
-
-    def get_album_tracks(self, album_id):
-        return self._tracks
-
-
-class _FakeDB:
-    def __init__(self, retag_tracks=None):
-        self._tracks = retag_tracks or []
-        self.path_updates = []
-        self.group_updates = []
-
-    def get_retag_tracks(self, group_id):
-        return self._tracks
-
-    def update_retag_track_path(self, track_id, new_path):
-        self.path_updates.append((track_id, new_path))
-
-    def update_retag_group(self, group_id, **kwargs):
-        self.group_updates.append((group_id, kwargs))
-
-
-def _build_deps(
-    *,
-    spotify_album=None,
-    spotify_tracks=None,
-    retag_tracks=None,
-    state=None,
-    enhance_calls=None,
-    move_calls=None,
-    cover_calls=None,
-    build_path_result=None,
-):
-    state = state if state is not None else {}
-    enhance_calls = enhance_calls if enhance_calls is not None else []
-    move_calls = move_calls if move_calls is not None else []
-    cover_calls = cover_calls if cover_calls is not None else []
-    db = _FakeDB(retag_tracks=retag_tracks or [])
-
-    deps = ret.RetagDeps(
-        config_manager=type('C', (), {'get': lambda self, k, d=None: d})(),
-        retag_lock=threading.Lock(),
-        spotify_client=_FakeSpotify(album=spotify_album, tracks=spotify_tracks),
-        get_audio_quality_string=lambda fp: 'FLAC 16bit',
-        enhance_file_metadata=lambda fp, ctx, artist, ai: enhance_calls.append((fp, ctx, artist, ai)),
-        build_final_path_for_track=lambda ctx, artist, ai, ext: (
-            (build_path_result if build_path_result is not None else ctx['original_search_result']['title'] + ext),
-            True,
-        ),
-        safe_move_file=lambda src, dst: move_calls.append((src, dst)),
-        cleanup_empty_directories=lambda transfer_dir, file_path: None,
-        download_cover_art=lambda ai, dest_dir, ctx: cover_calls.append((ai, dest_dir)),
-        docker_resolve_path=lambda p: p,
-        _get_retag_state=lambda: state,
-        _set_retag_state=lambda v: state.clear() or state.update(v),
-        get_database=lambda: db,
-    )
-    deps._db = db
-    deps._state = state
-    deps._enhance_calls = enhance_calls
-    deps._move_calls = move_calls
-    deps._cover_calls = cover_calls
-    return deps
-
-
-# ---------------------------------------------------------------------------
-# Setup error paths
-# ---------------------------------------------------------------------------
-
-def test_no_album_data_marks_state_error(tmp_path):
-    """spotify.get_album returning None → state.error_message set, state status='error'."""
-    deps = _build_deps(spotify_album=None)
-    ret.execute_retag('g1', 'alb-1', deps)
-    assert deps._state['status'] == 'error'
-    assert 'Could not fetch album' in deps._state['error_message']
-
-
-def test_no_album_tracks_marks_state_error():
-    """spotify.get_album_tracks returning None → error state."""
-    deps = _build_deps(spotify_album={'name': 'A', 'artists': []}, spotify_tracks=None)
-    ret.execute_retag('g1', 'alb-1', deps)
-    assert deps._state['status'] == 'error'
-
-
-def test_no_existing_tracks_marks_state_error():
-    """retag_group has no tracks → error state."""
-    deps = _build_deps(
-        spotify_album={'name': 'A', 'artists': [{'name': 'X', 'id': '1'}], 'images': [], 'release_date': '', 'total_tracks': 1},
-        spotify_tracks={'items': [{'name': 'T1', 'track_number': 1, 'disc_number': 1, 'id': 'sp1', 'artists': [], 'duration_ms': 1000}]},
-        retag_tracks=[],
-    )
-    ret.execute_retag('g1', 'alb-1', deps)
-    assert deps._state['status'] == 'error'
-    assert 'No tracks found' in deps._state['error_message']
-
-
-# ---------------------------------------------------------------------------
-# Successful retag — track-number match
-# ---------------------------------------------------------------------------
-
-def test_track_number_match_priority_1(tmp_path):
-    """Existing track with matching track+disc number → matched even if title differs."""
-    src_file = tmp_path / 'old.flac'
-    src_file.touch()
-
-    deps = _build_deps(
-        spotify_album={'name': 'New Album', 'artists': [{'name': 'Artist A', 'id': 'a1'}],
-                       'images': [{'url': 'http://img'}], 'release_date': '2024-01-01', 'total_tracks': 1},
-        spotify_tracks={'items': [{'name': 'Brand New Title', 'track_number': 5,
-                                    'disc_number': 1, 'id': 'sp5', 'artists': [{'name': 'X'}],
-                                    'duration_ms': 1000}]},
-        retag_tracks=[{
-            'id': 1,
-            'title': 'Completely Unrelated Old Name',
-            'track_number': 5,
-            'disc_number': 1,
-            'file_path': str(src_file),
-        }],
-        build_path_result=str(tmp_path / 'new.flac'),
-    )
-
-    ret.execute_retag('g1', 'alb-x', deps)
-
-    # Match found via priority 1 (track number) — enhance_file_metadata called
-    assert len(deps._enhance_calls) == 1
-    fp, ctx, artist, _ai = deps._enhance_calls[0]
-    assert fp == str(src_file)
-    assert ctx['original_search_result']['spotify_clean_title'] == 'Brand New Title'
-    # State marks finished
-    assert deps._state['status'] == 'finished'
-    assert deps._state['progress'] == 100
-
-
-# ---------------------------------------------------------------------------
-# Title-similarity fallback (priority 2)
-# ---------------------------------------------------------------------------
-
-def test_title_similarity_fallback_when_no_track_number_match():
-    """No track-number match → falls back to fuzzy title match."""
-    deps = _build_deps(
-        spotify_album={'name': 'A', 'artists': [{'name': 'X', 'id': '1'}], 'images': [],
-                       'release_date': '', 'total_tracks': 1},
-        spotify_tracks={'items': [{'name': 'Hello World', 'track_number': 99,
-                                    'disc_number': 99, 'id': 'sp1', 'artists': [],
-                                    'duration_ms': 1000}]},
-        retag_tracks=[{
-            'id': 1,
-            'title': 'Hello World',  # title matches
-            'track_number': 1, 'disc_number': 1,  # but numbers don't
-            'file_path': '/nonexistent/old.flac',
-        }],
-    )
-    ret.execute_retag('g1', 'alb-x', deps)
-
-    # File doesn't exist so enhance is skipped, but match was made
-    # (state.processed == 1 confirms loop iterated)
-    assert deps._state['processed'] == 1
-
-
-def test_no_match_skips_track():
-    """No track-number AND title similarity below 0.6 → no match, no enhance call."""
-    deps = _build_deps(
-        spotify_album={'name': 'A', 'artists': [{'name': 'X', 'id': '1'}], 'images': [],
-                       'release_date': '', 'total_tracks': 1},
-        spotify_tracks={'items': [{'name': 'Completely Different', 'track_number': 99,
-                                    'disc_number': 99, 'id': 'sp1', 'artists': [],
-                                    'duration_ms': 1000}]},
-        retag_tracks=[{
-            'id': 1,
-            'title': 'Hello World',
-            'track_number': 1, 'disc_number': 1,
-            'file_path': '/nonexistent/old.flac',
-        }],
-    )
-    ret.execute_retag('g1', 'alb-x', deps)
-
-    # No match, no enhance call
-    assert deps._enhance_calls == []
-    assert deps._state['processed'] == 1
-
-
-# ---------------------------------------------------------------------------
-# Missing file
-# ---------------------------------------------------------------------------
-
-def test_missing_file_skipped(tmp_path):
-    """If the audio file doesn't exist, enhance_file_metadata is NOT called."""
-    deps = _build_deps(
-        spotify_album={'name': 'A', 'artists': [{'name': 'X', 'id': '1'}], 'images': [],
-                       'release_date': '', 'total_tracks': 1},
-        spotify_tracks={'items': [{'name': 'T1', 'track_number': 1, 'disc_number': 1,
-                                    'id': 'sp1', 'artists': [], 'duration_ms': 1000}]},
-        retag_tracks=[{
-            'id': 1, 'title': 'T1', 'track_number': 1, 'disc_number': 1,
-            'file_path': '/this/path/does/not/exist.flac',
-        }],
-    )
-    ret.execute_retag('g1', 'alb-x', deps)
-
-    assert deps._enhance_calls == []
-    assert deps._state['status'] == 'finished'
-
-
-# ---------------------------------------------------------------------------
-# Path move
-# ---------------------------------------------------------------------------
-
-def test_file_moved_when_path_changes(tmp_path):
-    """When build_final_path_for_track returns a different path, file is moved."""
-    src_file = tmp_path / 'old.flac'
-    src_file.touch()
-    new_path = str(tmp_path / 'subdir' / 'new.flac')
-
-    deps = _build_deps(
-        spotify_album={'name': 'A', 'artists': [{'name': 'X', 'id': '1'}], 'images': [],
-                       'release_date': '', 'total_tracks': 1},
-        spotify_tracks={'items': [{'name': 'T1', 'track_number': 1, 'disc_number': 1,
-                                    'id': 'sp1', 'artists': [], 'duration_ms': 1000}]},
-        retag_tracks=[{
-            'id': 1, 'title': 'T1', 'track_number': 1, 'disc_number': 1,
-            'file_path': str(src_file),
-        }],
-        build_path_result=new_path,
-    )
-
-    ret.execute_retag('g1', 'alb-x', deps)
-
-    assert len(deps._move_calls) == 1
-    assert deps._move_calls[0] == (str(src_file), new_path)
-    assert (1, new_path) in deps._db.path_updates
-
-
-# ---------------------------------------------------------------------------
-# Group record update
-# ---------------------------------------------------------------------------
-
-def test_spotify_album_id_used_for_alphanumeric_id():
-    """Non-numeric album IDs → spotify_album_id set, itunes_album_id None."""
-    deps = _build_deps(
-        spotify_album={'name': 'A', 'artists': [{'name': 'X', 'id': '1'}], 'images': [],
-                       'release_date': '', 'total_tracks': 1},
-        spotify_tracks={'items': [{'name': 'T1', 'track_number': 1, 'disc_number': 1,
-                                    'id': 'sp1', 'artists': [], 'duration_ms': 1000}]},
-        retag_tracks=[{
-            'id': 1, 'title': 'T1', 'track_number': 1, 'disc_number': 1,
-            'file_path': '/missing.flac',
-        }],
-    )
-    ret.execute_retag('g1', 'spotify_alpha_id_xyz', deps)
-
-    assert len(deps._db.group_updates) == 1
-    _gid, kwargs = deps._db.group_updates[0]
-    assert kwargs['spotify_album_id'] == 'spotify_alpha_id_xyz'
-    assert kwargs['itunes_album_id'] is None
-
-
-def test_itunes_album_id_used_for_numeric_id():
-    """Numeric album IDs → itunes_album_id set, spotify_album_id None."""
-    deps = _build_deps(
-        spotify_album={'name': 'A', 'artists': [{'name': 'X', 'id': '1'}], 'images': [],
-                       'release_date': '', 'total_tracks': 1},
-        spotify_tracks={'items': [{'name': 'T1', 'track_number': 1, 'disc_number': 1,
-                                    'id': 'sp1', 'artists': [], 'duration_ms': 1000}]},
-        retag_tracks=[{
-            'id': 1, 'title': 'T1', 'track_number': 1, 'disc_number': 1,
-            'file_path': '/missing.flac',
-        }],
-    )
-    ret.execute_retag('g1', '987654321', deps)
-
-    _gid, kwargs = deps._db.group_updates[0]
-    assert kwargs['itunes_album_id'] == '987654321'
-    assert kwargs['spotify_album_id'] is None
-
-
-# ---------------------------------------------------------------------------
-# Multi-disc detection
-# ---------------------------------------------------------------------------
-
-def test_multi_disc_total_discs_computed():
-    """total_discs derived from max disc_number across all spotify tracks."""
-    deps = _build_deps(
-        spotify_album={'name': 'A', 'artists': [{'name': 'X', 'id': '1'}], 'images': [],
-                       'release_date': '', 'total_tracks': 3},
-        spotify_tracks={'items': [
-            {'name': 'T1', 'track_number': 1, 'disc_number': 1, 'id': 'sp1', 'artists': [], 'duration_ms': 1000},
-            {'name': 'T2', 'track_number': 1, 'disc_number': 2, 'id': 'sp2', 'artists': [], 'duration_ms': 1000},
-            {'name': 'T3', 'track_number': 1, 'disc_number': 3, 'id': 'sp3', 'artists': [], 'duration_ms': 1000},
-        ]},
-        retag_tracks=[{
-            'id': 1, 'title': 'T1', 'track_number': 1, 'disc_number': 1,
-            'file_path': '/missing.flac',
-        }],
-    )
-    ret.execute_retag('g1', 'alb-x', deps)
-
-    # Verify multi-disc reflected in retag — group update has total_tracks
-    # (total_discs not stored on group; check via state instead)
-    assert deps._state['status'] == 'finished'

tests/matching/test_artist_alias_service.py

@@ -270,6 +270,7 @@ class TestWorkerAliasEnrichment:
 
         worker = MusicBrainzWorker.__new__(MusicBrainzWorker)
         worker.database = temp_db
+        worker.db = temp_db  # worker code uses self.db (e.g. source_id_conflict)
         worker.mb_service = MagicMock()
         worker.mb_service.match_artist.return_value = {
             'mbid': '60d2ea34-1912-425f-bf9c-fc544e4448cd', 'name': 'Hiroyuki Sawano',
@@ -300,6 +301,7 @@ class TestWorkerAliasEnrichment:
 
         worker = MusicBrainzWorker.__new__(MusicBrainzWorker)
         worker.database = temp_db
+        worker.db = temp_db  # worker code uses self.db (e.g. source_id_conflict)
         worker.mb_service = MagicMock()
         worker.mb_service.match_artist.return_value = None
         worker.stats = {'matched': 0, 'not_found': 0, 'errors': 0}
@@ -392,6 +394,7 @@ class TestWorkerAliasEnrichment:
 
         worker = MusicBrainzWorker.__new__(MusicBrainzWorker)
         worker.database = temp_db
+        worker.db = temp_db  # worker code uses self.db (e.g. source_id_conflict)
         worker.mb_service = MagicMock()
         worker.mb_service.match_artist.return_value = {'mbid': 'mb-x', 'name': 'X'}
         worker.mb_service.fetch_artist_aliases.side_effect = Exception("boom")

tests/matching/test_script_compat.py

@@ -0,0 +1,79 @@
+"""Tests for core/matching/script_compat.py — writing-system detection.
+
+Issue #797 — these pin the exact boundary that the AcoustID verifier
+relies on: accented Latin is still Latin (no false cross-script
+trigger), but genuinely different writing systems (CJK / Hangul /
+Cyrillic / Greek / Arabic / Hebrew / Thai) ARE flagged so a
+romanized-vs-native artist comparison isn't treated as a real mismatch.
+"""
+
+from __future__ import annotations
+
+import pytest
+
+from core.matching.script_compat import (
+    has_strong_nonlatin,
+    is_cross_script_mismatch,
+)
+
+
+# ---------------------------------------------------------------------------
+# has_strong_nonlatin — accented Latin must NOT count
+# ---------------------------------------------------------------------------
+
+@pytest.mark.parametrize('text', [
+    'Beyoncé', 'Sigur Rós', 'Mötley Crüe', 'Joe Hisaishi',
+    'Kendrick Lamar', 'Dmitry Yablonsky', 'AC/DC', 'P!nk',
+    '', '   ', '12345', 'Café del Mar',
+])
+def test_latin_and_accented_latin_is_not_nonlatin(text):
+    assert has_strong_nonlatin(text) is False
+
+
+@pytest.mark.parametrize('text', [
+    '久石譲',                 # kanji (Joe Hisaishi)
+    '残酷な天使のテーゼ',        # kana + kanji
+    'Дмитрий Яблонский',     # Cyrillic
+    '방탄소년단',              # Hangul (BTS)
+    'Σωκράτης',              # Greek
+    'عمرو دياب',             # Arabic
+    'שלום',                  # Hebrew
+    'ก้อง สหรัถ',            # Thai
+])
+def test_real_nonlatin_scripts_detected(text):
+    assert has_strong_nonlatin(text) is True
+
+
+# ---------------------------------------------------------------------------
+# is_cross_script_mismatch — the verifier's gate
+# ---------------------------------------------------------------------------
+
+def test_romanized_vs_native_is_cross_script():
+    # The reported case (#797): expected romanized, AcoustID native.
+    assert is_cross_script_mismatch('Joe Hisaishi', '久石譲') is True
+    assert is_cross_script_mismatch('Dmitry Yablonsky', 'Дмитрий Яблонский') is True
+
+
+def test_is_symmetric():
+    assert is_cross_script_mismatch('久石譲', 'Joe Hisaishi') is True
+
+
+def test_same_latin_both_sides_is_not_mismatch():
+    # English-vs-English — comparison is meaningful, no bridge. This is
+    # the Kendrick R.O.T.C protection surface: must stay False so the
+    # verifier keeps its strict FAIL path.
+    assert is_cross_script_mismatch('Kendrick Lamar', 'Kendrick Lamar feat. BJ') is False
+    assert is_cross_script_mismatch('Crown', 'Crown of Thorns') is False
+
+
+def test_same_nonlatin_both_sides_is_not_mismatch():
+    # Both native — same-script similarity still works, don't relax.
+    assert is_cross_script_mismatch('久石譲', '久石譲') is False
+    assert is_cross_script_mismatch('久石譲', '坂本龍一') is False
+
+
+def test_empty_or_letterless_other_side_is_not_mismatch():
+    # One side non-Latin but the other has no Latin LETTER to bridge to.
+    assert is_cross_script_mismatch('', '久石譲') is False
+    assert is_cross_script_mismatch('12345', '久石譲') is False
+    assert is_cross_script_mismatch('久石譲', '   ') is False

tests/media_server/test_navidrome_pinning.py

@@ -79,6 +79,82 @@ def test_get_all_album_ids_returns_set(nav_client):
     assert result == {'nav-1', 'nav-2'}
 
 
+def test_fetch_music_folders_parses_without_ensure_connection(nav_client):
+    """The seam: _fetch_music_folders does its own _make_request + parse and
+    does NOT gate on ensure_connection, so it is safe to call mid-connect."""
+    nav_client.base_url = 'http://nav'
+    nav_client.username = 'u'
+    nav_client.password = 'p'
+    folders_envelope = {'musicFolders': {'musicFolder': [
+        {'id': 1, 'name': 'Music'},
+        {'id': 2, 'name': 'Audiobooks'},
+    ]}}
+    with patch.object(nav_client, '_make_request', return_value=folders_envelope):
+        folders = nav_client._fetch_music_folders()
+    assert folders == [
+        {'title': 'Music', 'key': '1'},
+        {'title': 'Audiobooks', 'key': '2'},
+    ]
+
+
+def _fake_request(endpoint, params=None):
+    if endpoint == 'ping':
+        return {'status': 'ok', 'version': '1.16.1'}
+    if endpoint == 'getMusicFolders':
+        return {'musicFolders': {'musicFolder': [
+            {'id': 1, 'name': 'Music'},
+            {'id': 2, 'name': 'Audiobooks'},
+        ]}}
+    return None
+
+
+def _prefs(values):
+    """A MusicDatabase mock whose get_preference reads from `values`."""
+    db = MagicMock()
+    db.get_preference.side_effect = lambda key, *a, **k: values.get(key)
+    return db
+
+
+def _connect_with(nav_client, fake_db):
+    with patch('core.navidrome_client.config_manager.get_navidrome_config',
+               return_value={'base_url': 'http://nav', 'username': 'u', 'password': 'p'}), \
+         patch('database.music_database.MusicDatabase', return_value=fake_db), \
+         patch.object(nav_client, '_make_request', side_effect=_fake_request):
+        assert nav_client.ensure_connection() is True
+
+
+def test_setup_client_restores_saved_music_folder(nav_client):
+    """Regression for #789: a saved music-folder selection must survive
+    _setup_client. The restore runs while still inside ensure_connection()
+    (_is_connecting=True); the old code called the public get_music_folders(),
+    which re-entered the guard, got [], and left music_folder_id=None — so
+    every scan imported all libraries regardless of the user's selection."""
+    fake_db = _prefs({'navidrome_music_folder_id': '2', 'navidrome_music_folder': 'Audiobooks'})
+    _connect_with(nav_client, fake_db)
+    assert nav_client.music_folder_id == '2'
+    # Nothing drifted → no self-heal writes.
+    fake_db.set_preference.assert_not_called()
+
+
+def test_setup_client_restores_by_id_after_folder_rename(nav_client):
+    """Hardening: the id is the primary key, so a folder renamed in Navidrome
+    (stored name no longer matches its title) still resolves by id — and the
+    stale name is healed so the settings dropdown stays correct."""
+    fake_db = _prefs({'navidrome_music_folder_id': '2', 'navidrome_music_folder': 'Old Stale Name'})
+    _connect_with(nav_client, fake_db)
+    assert nav_client.music_folder_id == '2'
+    fake_db.set_preference.assert_any_call('navidrome_music_folder', 'Audiobooks')
+
+
+def test_setup_client_name_fallback_self_heals_id(nav_client):
+    """Back-compat: installs saved before the id was persisted match by name,
+    and the id is written back so a later rename can't break the match."""
+    fake_db = _prefs({'navidrome_music_folder_id': None, 'navidrome_music_folder': 'Audiobooks'})
+    _connect_with(nav_client, fake_db)
+    assert nav_client.music_folder_id == '2'
+    fake_db.set_preference.assert_any_call('navidrome_music_folder_id', '2')
+
+
 def test_navidrome_album_exposes_cover_art_url(nav_client):
     album = NavidromeAlbum({
         'id': 'album-1',

tests/metadata/test_artist_source_lookup.py

@@ -164,6 +164,45 @@ class TestFindLibraryArtistForSource:
         )
         assert result is None
 
+    def test_ambiguous_source_id_skips_id_upgrade(self, db):
+        """Regression for the Kendrick/Jorja bug: when one Deezer id is
+        stamped on several library artists (enrichment corruption), the id
+        match is ambiguous and must NOT pick an arbitrary row — it returns
+        None so the caller falls back to showing the source artist."""
+        _insert_artist(db, artist_id="pk-kendrick", name="Kendrick Lamar",
+                       deezer_id="525046", server_source="plex")
+        _insert_artist(db, artist_id="pk-jorja", name="Jorja Smith",
+                       deezer_id="525046", server_source="plex")
+        _insert_artist(db, artist_id="pk-vince", name="Vince Staples",
+                       deezer_id="525046", server_source="plex")
+
+        # No name hint (the URL-driven path) → no id guess, no name fallback.
+        assert find_library_artist_for_source(
+            db, "deezer", "525046", active_server="plex"
+        ) is None
+
+    def test_ambiguous_source_id_still_allows_name_fallback(self, db):
+        """An ambiguous id shouldn't block a correct name match when the
+        caller does have the name."""
+        _insert_artist(db, artist_id="pk-kendrick", name="Kendrick Lamar",
+                       deezer_id="525046", server_source="plex")
+        _insert_artist(db, artist_id="pk-jorja", name="Jorja Smith",
+                       deezer_id="525046", server_source="plex")
+
+        result = find_library_artist_for_source(
+            db, "deezer", "525046", artist_name="Kendrick Lamar",
+            active_server="plex",
+        )
+        assert result == "pk-kendrick"
+
+    def test_unique_source_id_still_matches(self, db):
+        """Positive control: a non-duplicated id still upgrades as before."""
+        _insert_artist(db, artist_id="pk-solo", name="Solo Artist",
+                       deezer_id="999999", server_source="plex")
+        assert find_library_artist_for_source(
+            db, "deezer", "999999"
+        ) == "pk-solo"
+
     def test_id_match_wins_over_name_match(self, db):
         """If both a source-id match and a name match exist, the id match
         should take priority — it's the more reliable signal."""

tests/search/test_search_by_id.py

@@ -0,0 +1,451 @@
+"""Tests for core/search/by_id.py — paste-a-link/ID metadata resolution (#775).
+
+Covers the three seams:
+
+- ``parse_metadata_identifier`` — provider URLs, the ``spotify:`` URI, and
+  bare IDs (UUID → MusicBrainz, base62 → Spotify, numeric → Deezer/iTunes
+  fan-out with active-source bias).
+- the shaping adapters — projecting each source's get-by-id dict (which
+  differ in their ``artists`` field shape) onto the common card shape.
+- ``resolve_identifier`` — first-resolving-target-wins, kind fallback
+  (album→track), source fan-out, and the not-found regression.
+
+Clients are injected via ``client_resolver`` so nothing touches the network
+or real config.
+"""
+
+from __future__ import annotations
+
+from core.search import by_id
+from core.search.by_id import LookupTarget
+
+
+# ---------------------------------------------------------------------------
+# Fakes — a client exposing only the get-by-id methods the resolver calls.
+# Each "source" can return album/track dicts in its native shape.
+# ---------------------------------------------------------------------------
+
+class _FakeClient:
+    def __init__(self, album=None, track=None, artist=None, name='fake'):
+        self._album = album
+        self._track = track
+        self._artist = artist
+        self._name = name
+        self.album_calls: list[str] = []
+        self.track_calls: list[str] = []
+        self.artist_calls: list[str] = []
+
+    # Spotify / iTunes / MusicBrainz album-by-id
+    def get_album(self, identifier, include_tracks=True):
+        self.album_calls.append(identifier)
+        return self._album
+
+    # Deezer album-by-id (different method name)
+    def get_album_metadata(self, identifier, include_tracks=True):
+        self.album_calls.append(identifier)
+        return self._album
+
+    # Uniform track-by-id
+    def get_track_details(self, identifier):
+        self.track_calls.append(identifier)
+        return self._track
+
+    # Spotify / iTunes / MusicBrainz artist-by-id
+    def get_artist(self, identifier):
+        self.artist_calls.append(identifier)
+        return self._artist
+
+    # Deezer artist-by-id (different method name)
+    def get_artist_info(self, identifier):
+        self.artist_calls.append(identifier)
+        return self._artist
+
+
+def _resolver_from(mapping):
+    """Build a client_resolver from {source: client}."""
+    return lambda source: mapping.get(source)
+
+
+# ---------------------------------------------------------------------------
+# parse_metadata_identifier — URLs
+# ---------------------------------------------------------------------------
+
+def test_parse_spotify_album_url():
+    out = by_id.parse_metadata_identifier(
+        'https://open.spotify.com/album/4aawyAB9vmqN3uQ7FjRGTy'
+    )
+    assert out == [LookupTarget('spotify', 'album', '4aawyAB9vmqN3uQ7FjRGTy')]
+
+
+def test_parse_spotify_track_url_with_intl_prefix():
+    out = by_id.parse_metadata_identifier(
+        'https://open.spotify.com/intl-de/track/11dFghVXANMlKmJXsNCbNl'
+    )
+    assert out == [LookupTarget('spotify', 'track', '11dFghVXANMlKmJXsNCbNl')]
+
+
+def test_parse_spotify_uri():
+    assert by_id.parse_metadata_identifier('spotify:album:ABC') == [
+        LookupTarget('spotify', 'album', 'ABC')
+    ]
+    assert by_id.parse_metadata_identifier('spotify:track:XYZ') == [
+        LookupTarget('spotify', 'track', 'XYZ')
+    ]
+
+
+def test_parse_apple_album_url():
+    out = by_id.parse_metadata_identifier(
+        'https://music.apple.com/us/album/in-rainbows/1109714933'
+    )
+    assert out == [LookupTarget('itunes', 'album', '1109714933')]
+
+
+def test_parse_apple_track_url_uses_i_param():
+    out = by_id.parse_metadata_identifier(
+        'https://music.apple.com/us/album/in-rainbows/1109714933?i=1109714934'
+    )
+    assert out == [LookupTarget('itunes', 'track', '1109714934')]
+
+
+def test_parse_apple_song_url():
+    out = by_id.parse_metadata_identifier(
+        'https://music.apple.com/us/song/15-step/1109714938'
+    )
+    assert out == [LookupTarget('itunes', 'track', '1109714938')]
+
+
+def test_parse_musicbrainz_release_group_url():
+    mbid = 'a1b2c3d4-e5f6-7890-abcd-ef1234567890'
+    out = by_id.parse_metadata_identifier(
+        f'https://musicbrainz.org/release-group/{mbid}'
+    )
+    assert out == [LookupTarget('musicbrainz', 'album', mbid)]
+
+
+def test_parse_musicbrainz_recording_url_is_track():
+    mbid = 'a1b2c3d4-e5f6-7890-abcd-ef1234567890'
+    out = by_id.parse_metadata_identifier(
+        f'https://musicbrainz.org/recording/{mbid}'
+    )
+    assert out == [LookupTarget('musicbrainz', 'track', mbid)]
+
+
+def test_parse_deezer_album_url_with_locale():
+    out = by_id.parse_metadata_identifier('https://www.deezer.com/en/album/302127')
+    assert out == [LookupTarget('deezer', 'album', '302127')]
+
+
+def test_parse_deezer_track_url_no_scheme():
+    out = by_id.parse_metadata_identifier('www.deezer.com/track/3135556')
+    assert out == [LookupTarget('deezer', 'track', '3135556')]
+
+
+def test_parse_spotify_url_without_scheme_or_www():
+    # Known host detected even without a scheme.
+    out = by_id.parse_metadata_identifier('open.spotify.com/album/4aawyAB9vmqN3uQ7FjRGTy')
+    assert out == [LookupTarget('spotify', 'album', '4aawyAB9vmqN3uQ7FjRGTy')]
+
+
+# ---------------------------------------------------------------------------
+# parse_metadata_identifier — artist links
+# ---------------------------------------------------------------------------
+
+def test_parse_spotify_artist_url():
+    out = by_id.parse_metadata_identifier(
+        'https://open.spotify.com/artist/3TVXtAsR1Inumwj472S9r4'
+    )
+    assert out == [LookupTarget('spotify', 'artist', '3TVXtAsR1Inumwj472S9r4')]
+
+
+def test_parse_spotify_artist_uri():
+    assert by_id.parse_metadata_identifier('spotify:artist:ABC') == [
+        LookupTarget('spotify', 'artist', 'ABC')
+    ]
+
+
+def test_parse_apple_artist_url():
+    out = by_id.parse_metadata_identifier(
+        'https://music.apple.com/us/artist/kendrick-lamar/368183298'
+    )
+    assert out == [LookupTarget('itunes', 'artist', '368183298')]
+
+
+def test_parse_musicbrainz_artist_url():
+    mbid = 'a1b2c3d4-e5f6-7890-abcd-ef1234567890'
+    out = by_id.parse_metadata_identifier(f'https://musicbrainz.org/artist/{mbid}')
+    assert out == [LookupTarget('musicbrainz', 'artist', mbid)]
+
+
+def test_parse_deezer_artist_url():
+    out = by_id.parse_metadata_identifier('https://www.deezer.com/artist/13')
+    assert out == [LookupTarget('deezer', 'artist', '13')]
+
+
+# ---------------------------------------------------------------------------
+# parse_metadata_identifier — bare IDs are rejected (links only)
+# ---------------------------------------------------------------------------
+
+def test_parse_bare_numeric_id_rejected():
+    # The footgun case (#775 follow-up): a bare number has no source/type, so
+    # it must NOT resolve to whatever album happens to own that id.
+    assert by_id.parse_metadata_identifier('525046') == []
+
+
+def test_parse_bare_uuid_rejected():
+    assert by_id.parse_metadata_identifier(
+        'a1b2c3d4-e5f6-7890-abcd-ef1234567890'
+    ) == []
+
+
+def test_parse_bare_base62_rejected():
+    assert by_id.parse_metadata_identifier('4aawyAB9vmqN3uQ7FjRGTy') == []
+
+
+def test_parse_empty_and_garbage_return_empty():
+    assert by_id.parse_metadata_identifier('') == []
+    assert by_id.parse_metadata_identifier('   ') == []
+    assert by_id.parse_metadata_identifier('not an id!!') == []
+    # Unknown domain → no targets.
+    assert by_id.parse_metadata_identifier('https://example.com/album/1') == []
+
+
+# ---------------------------------------------------------------------------
+# Shaping adapters
+# ---------------------------------------------------------------------------
+
+def test_album_card_from_spotify_shaped_dict():
+    d = {
+        'id': 'abc',
+        'name': 'OK Computer',
+        'artists': [{'name': 'Radiohead', 'id': 'r1'}],
+        'images': [{'url': 'http://img/big.jpg', 'height': 640, 'width': 640}],
+        'release_date': '1997-05-21',
+        'total_tracks': 12,
+        'album_type': 'album',
+        'external_urls': {'spotify': 'http://spot/abc'},
+    }
+    card = by_id.album_dict_to_card(d)
+    assert card['id'] == 'abc'
+    assert card['name'] == 'OK Computer'
+    assert card['artist'] == 'Radiohead'
+    assert card['image_url'] == 'http://img/big.jpg'
+    assert card['total_tracks'] == 12
+    assert card['external_urls'] == {'spotify': 'http://spot/abc'}
+
+
+def test_album_card_carries_optional_musicbrainz_fields():
+    d = {
+        'id': 'mbid', 'name': 'Kid A', 'artists': [{'name': 'Radiohead'}],
+        'images': [], 'release_date': '2000', 'total_tracks': 10,
+        'album_type': 'album', 'country': 'GB', 'label': 'Parlophone',
+        'release_group_id': 'rg1', 'external_urls': {},
+    }
+    card = by_id.album_dict_to_card(d)
+    assert card['country'] == 'GB'
+    assert card['label'] == 'Parlophone'
+    assert card['release_group_id'] == 'rg1'
+
+
+def test_track_card_handles_list_of_string_artists():
+    # Spotify/iTunes shape: artists is a list of plain strings.
+    d = {
+        'id': 't1', 'name': 'Paranoid Android',
+        'artists': ['Radiohead'],
+        'album': {'name': 'OK Computer', 'release_date': '1997'},
+        'duration_ms': 387000,
+    }
+    card = by_id.track_dict_to_card(d)
+    assert card['artist'] == 'Radiohead'
+    assert card['album'] == 'OK Computer'
+    assert card['duration_ms'] == 387000
+    assert card['release_date'] == '1997'
+
+
+def test_track_card_handles_list_of_dict_artists_and_album_image():
+    # MusicBrainz shape: artists is a list of dicts; album carries images.
+    d = {
+        'id': 't2', 'name': 'Idioteque',
+        'artists': [{'name': 'Radiohead', 'id': ''}],
+        'album': {
+            'name': 'Kid A',
+            'images': [{'url': 'http://img/kida.jpg', 'height': 250, 'width': 250}],
+            'release_date': '2000',
+        },
+        'duration_ms': 300000,
+        'external_urls': {'musicbrainz': 'http://mb/t2'},
+    }
+    card = by_id.track_dict_to_card(d)
+    assert card['artist'] == 'Radiohead'
+    assert card['album'] == 'Kid A'
+    assert card['image_url'] == 'http://img/kida.jpg'
+    assert card['external_urls'] == {'musicbrainz': 'http://mb/t2'}
+
+
+def test_join_artists_empty_is_unknown():
+    assert by_id._join_artists([]) == 'Unknown Artist'
+    assert by_id._join_artists(None) == 'Unknown Artist'
+
+
+def test_artist_card_from_spotify_shaped_dict():
+    d = {
+        'id': 'a1', 'name': 'Radiohead',
+        'images': [{'url': 'http://img/rh.jpg', 'height': 640, 'width': 640}],
+        'external_urls': {'spotify': 'http://spot/a1'},
+        'genres': ['rock'], 'popularity': 80,
+    }
+    card = by_id.artist_dict_to_card(d)
+    assert card == {
+        'id': 'a1',
+        'name': 'Radiohead',
+        'image_url': 'http://img/rh.jpg',
+        'external_urls': {'spotify': 'http://spot/a1'},
+    }
+
+
+# ---------------------------------------------------------------------------
+# resolve_identifier — end-to-end with fake clients
+# ---------------------------------------------------------------------------
+
+_SPOTIFY_ALBUM = {
+    'id': 'abc', 'name': 'OK Computer',
+    'artists': [{'name': 'Radiohead'}],
+    'images': [{'url': 'http://i/a.jpg'}],
+    'release_date': '1997', 'total_tracks': 12, 'album_type': 'album',
+    'external_urls': {'spotify': 'http://s/abc'},
+}
+
+
+def test_resolve_spotify_album_link():
+    client = _FakeClient(album=_SPOTIFY_ALBUM)
+    res = by_id.resolve_identifier(
+        'https://open.spotify.com/album/abc', deps=None,
+        client_resolver=_resolver_from({'spotify': client}),
+    )
+    assert res['available'] is True
+    assert res['source'] == 'spotify'
+    assert len(res['albums']) == 1
+    assert res['albums'][0]['name'] == 'OK Computer'
+    assert res['tracks'] == []
+    assert client.album_calls == ['abc']
+    assert client.track_calls == []  # kind pinned to album — no track probe
+
+
+def test_resolve_deezer_album_uses_get_album_metadata():
+    client = _FakeClient(album={'id': '302127', 'name': 'Discovery',
+                                'artists': [{'name': 'Daft Punk'}], 'images': [],
+                                'release_date': '2001', 'total_tracks': 14,
+                                'album_type': 'album', 'external_urls': {}})
+    res = by_id.resolve_identifier(
+        'https://www.deezer.com/album/302127', deps=None,
+        client_resolver=_resolver_from({'deezer': client}),
+    )
+    assert res['available'] is True
+    assert res['source'] == 'deezer'
+    assert res['albums'][0]['name'] == 'Discovery'
+    assert client.album_calls == ['302127']
+
+
+def test_resolve_track_link():
+    # A track URL pins kind=track — only get_track_details is called.
+    client = _FakeClient(album=None, track={
+        'id': 't1', 'name': 'Creep', 'artists': ['Radiohead'],
+        'album': {'name': 'Pablo Honey'}, 'duration_ms': 238000,
+    })
+    res = by_id.resolve_identifier(
+        'https://open.spotify.com/track/t1', deps=None,
+        client_resolver=_resolver_from({'spotify': client}),
+    )
+    assert res['available'] is True
+    assert res['tracks'][0]['name'] == 'Creep'
+    assert res['albums'] == []
+    assert client.album_calls == []      # kind pinned to track — no album probe
+    assert client.track_calls == ['t1']
+
+
+def test_resolve_artist_link():
+    # An artist URL pins kind=artist — only get_artist is called.
+    client = _FakeClient(artist={
+        'id': 'a1', 'name': 'Radiohead',
+        'images': [{'url': 'http://i/rh.jpg'}],
+        'external_urls': {'spotify': 'http://s/a1'},
+    })
+    res = by_id.resolve_identifier(
+        'https://open.spotify.com/artist/a1', deps=None,
+        client_resolver=_resolver_from({'spotify': client}),
+    )
+    assert res['available'] is True
+    assert res['source'] == 'spotify'
+    assert res['artists'][0]['name'] == 'Radiohead'
+    assert res['albums'] == [] and res['tracks'] == []
+    assert client.artist_calls == ['a1']
+    assert client.album_calls == [] and client.track_calls == []
+
+
+def test_resolve_deezer_artist_uses_get_artist_info():
+    client = _FakeClient(artist={'id': '13', 'name': 'Daft Punk',
+                                 'images': [], 'external_urls': {}})
+    res = by_id.resolve_identifier(
+        'https://www.deezer.com/artist/13', deps=None,
+        client_resolver=_resolver_from({'deezer': client}),
+    )
+    assert res['available'] is True
+    assert res['source'] == 'deezer'
+    assert res['artists'][0]['name'] == 'Daft Punk'
+    assert client.artist_calls == ['13']
+
+
+def test_resolve_bare_id_rejected_with_hint():
+    # The #775 follow-up regression: a bare number must not resolve; it
+    # returns not-found with a link hint instead of an unrelated album.
+    called = []
+    res = by_id.resolve_identifier(
+        '525046', deps=None,
+        client_resolver=lambda s: called.append(s),  # must never be invoked
+    )
+    assert res['available'] is False
+    assert res['albums'] == [] and res['tracks'] == []
+    assert 'link' in res['message'].lower()
+    assert called == []  # no source was even probed
+
+
+def test_resolve_unavailable_client_is_skipped():
+    # Spotify client is None (unauthed) — resolver returns not-found, no crash.
+    res = by_id.resolve_identifier(
+        'https://open.spotify.com/album/abc', deps=None,
+        client_resolver=_resolver_from({'spotify': None}),
+    )
+    assert res['available'] is False
+    assert res['albums'] == [] and res['tracks'] == []
+    # The source we tried is reported even on miss.
+    assert res['source'] == 'spotify'
+    assert res['message']
+
+
+def test_resolve_client_exception_does_not_propagate():
+    def boom(_source):
+        raise RuntimeError('client init failed')
+    res = by_id.resolve_identifier(
+        'https://open.spotify.com/album/abc', deps=None, client_resolver=boom,
+    )
+    assert res['available'] is False
+
+
+def test_resolve_unrecognized_identifier_returns_empty():
+    res = by_id.resolve_identifier(
+        'definitely not a link', deps=None,
+        client_resolver=_resolver_from({}),
+    )
+    assert res['available'] is False
+    assert res['query'] == 'definitely not a link'
+
+
+def test_resolve_get_album_returning_none_yields_not_found():
+    # Regression: a pinned-kind link whose lookup returns None must report
+    # not-found, not raise or fabricate a card.
+    client = _FakeClient(album=None)
+    res = by_id.resolve_identifier(
+        'https://open.spotify.com/album/missing', deps=None,
+        client_resolver=_resolver_from({'spotify': client}),
+    )
+    assert res['available'] is False
+    assert res['albums'] == []

tests/search/test_search_orchestrator.py

@@ -50,7 +50,7 @@ class _Track:
 
 class _Client:
     def __init__(self, *, name='fake', artists=None, albums=None, tracks=None,
-                 fail_search=False, authed=True, connected=True):
+                 fail_search=False, authed=True, connected=True, meta_available=None):
         self.name = name
         self._artists = artists or []
         self._albums = albums or []
@@ -58,6 +58,10 @@ class _Client:
         self._fail = fail_search
         self._authed = authed
         self._connected = connected
+        # When unset, metadata availability tracks auth (the common case). Set
+        # explicitly to model the no-creds SpotipyFree fallback: not authed but
+        # metadata still available.
+        self._meta_available = meta_available
 
     def search_artists(self, q, limit=10):
         if self._fail:
@@ -77,6 +81,9 @@ class _Client:
     def is_spotify_authenticated(self):
         return self._authed
 
+    def is_spotify_metadata_available(self):
+        return self._authed if self._meta_available is None else self._meta_available
+
     def is_connected(self):
         return self._connected
 
@@ -157,12 +164,22 @@ def test_resolve_spotify_authed_returns_client():
 
 
 def test_resolve_spotify_unauthed_returns_none():
-    deps = _build_deps(spotify_client=_Client(authed=False))
+    # No auth AND no free fallback available → Spotify source unavailable.
+    deps = _build_deps(spotify_client=_Client(authed=False, meta_available=False))
     client, ok = orchestrator.resolve_client('spotify', deps)
     assert client is None
     assert ok is False
 
 
+def test_resolve_spotify_unauthed_but_free_available_returns_client():
+    # #798: no Spotify auth but the no-creds SpotipyFree fallback is available →
+    # the Spotify source stays usable (the client routes to free internally).
+    deps = _build_deps(spotify_client=_Client(authed=False, meta_available=True))
+    client, ok = orchestrator.resolve_client('spotify', deps)
+    assert client is deps.spotify_client
+    assert ok is True
+
+
 def test_resolve_spotify_missing_returns_none():
     deps = _build_deps(spotify_client=None)
     client, ok = orchestrator.resolve_client('spotify', deps)

tests/sync/test_match_overrides.py

@@ -1,6 +1,10 @@
 from unittest.mock import MagicMock
 
-from core.sync.match_overrides import record_manual_match, resolve_match_overrides
+from core.sync.match_overrides import (
+    record_manual_match,
+    resolve_durable_match_server_id,
+    resolve_match_overrides,
+)
 
 
 # ──────────────────────────────────────────────────────────────────────
@@ -191,3 +195,84 @@ def test_record_handles_empty_optional_strings():
     assert kwargs["normalized_title"] == ""
     assert kwargs["normalized_artist"] == ""
     assert kwargs["server_track_title"] == ""
+
+
+# ──────────────────────────────────────────────────────────────────────
+# resolve_durable_match_server_id — manual match survives a rescan (#787)
+# ──────────────────────────────────────────────────────────────────────
+
+class _FakeMatchDB:
+    """Minimal DB stub for the durable-match resolver."""
+    def __init__(self, match=None, file_path_id=None):
+        self._match = match
+        self._file_path_id = file_path_id
+        self.saved = []
+
+    def find_manual_library_match_by_source_track_id(self, profile_id, source_track_id, server_source):
+        return dict(self._match) if self._match else None
+
+    def find_track_id_by_file_path(self, file_path):
+        return self._file_path_id
+
+    def save_manual_library_match(self, profile_id, source, source_track_id, library_track_id, **meta):
+        self.saved.append((library_track_id, meta))
+        return True
+
+
+def test_durable_match_returns_id_when_still_valid():
+    # Stored library id still present in the server playlist → direct hit.
+    db = _FakeMatchDB(match={"library_track_id": "5001", "library_file_path": "/m/a.flac",
+                             "profile_id": 1, "source": "spotify", "source_track_id": "iron",
+                             "server_source": "plex"})
+    out = resolve_durable_match_server_id(db, 1, "iron", "plex", {"5001", "5002"})
+    assert out == "5001"
+    assert db.saved == []  # no self-heal needed
+
+
+def test_durable_match_reresolves_stale_id_via_file_path_and_self_heals():
+    # Rescan re-keyed the track: old id 5001 gone, file now lives at id 7777.
+    db = _FakeMatchDB(
+        match={"library_track_id": "5001", "library_file_path": "/m/a.flac",
+               "profile_id": 1, "source": "spotify", "source_track_id": "iron", "server_source": "plex"},
+        file_path_id="7777",
+    )
+    out = resolve_durable_match_server_id(db, 1, "iron", "plex", {"7777", "9000"})
+    assert out == "7777"                      # re-resolved to the current id
+    assert db.saved and db.saved[0][0] == "7777"  # self-healed the stored id
+
+
+def test_durable_match_none_when_no_match():
+    db = _FakeMatchDB(match=None)
+    assert resolve_durable_match_server_id(db, 1, "iron", "plex", {"5001"}) is None
+
+
+def test_durable_match_none_when_stale_and_file_path_unresolvable():
+    # Stale id AND the file path no longer resolves (file moved/removed) → no pair.
+    db = _FakeMatchDB(
+        match={"library_track_id": "5001", "library_file_path": "/m/gone.flac",
+               "profile_id": 1, "source": "spotify", "source_track_id": "iron", "server_source": "plex"},
+        file_path_id=None,
+    )
+    assert resolve_durable_match_server_id(db, 1, "iron", "plex", {"7777"}) is None
+    assert db.saved == []
+
+
+def test_durable_match_none_when_reresolved_id_not_in_playlist():
+    # File resolves to a track, but that track isn't in THIS playlist → don't pair.
+    db = _FakeMatchDB(
+        match={"library_track_id": "5001", "library_file_path": "/m/a.flac",
+               "profile_id": 1, "source": "spotify", "source_track_id": "iron", "server_source": "plex"},
+        file_path_id="7777",
+    )
+    assert resolve_durable_match_server_id(db, 1, "iron", "plex", {"1234"}) is None
+
+
+def test_durable_match_safe_when_db_lacks_methods():
+    class Bare:
+        pass
+    assert resolve_durable_match_server_id(Bare(), 1, "iron", "plex", {"5001"}) is None
+
+
+def test_durable_match_empty_source_id_returns_none():
+    db = _FakeMatchDB(match={"library_track_id": "5001"})
+    assert resolve_durable_match_server_id(db, 1, "", "plex", {"5001"}) is None

tests/sync/test_reconcile_or_replace.py

@@ -0,0 +1,67 @@
+"""sync_mode='reconcile' dispatch + fallback (#792).
+
+_reconcile_or_replace tries the client's in-place reconcile and falls back to
+the destructive replace only when reconcile is unavailable or fails, so a sync
+always succeeds while preferring the non-destructive path.
+"""
+
+import sys
+import types
+
+# Stub optional Spotify dep so services.sync_service imports in the test env.
+if 'spotipy' not in sys.modules:
+    sp = types.ModuleType('spotipy'); oa = types.ModuleType('spotipy.oauth2')
+    sp.Spotify = type('S', (), {}); oa.SpotifyOAuth = oa.SpotifyClientCredentials = type('O', (), {})
+    sp.oauth2 = oa; sys.modules['spotipy'] = sp; sys.modules['spotipy.oauth2'] = oa
+
+from services.sync_service import PlaylistSyncService
+
+
+def _service():
+    return PlaylistSyncService.__new__(PlaylistSyncService)
+
+
+class _Client:
+    def __init__(self, reconcile=None):
+        self._reconcile = reconcile
+        self.reconcile_calls = []
+        self.replace_calls = []
+        if reconcile is not None:
+            def reconcile_playlist(name, tracks):
+                self.reconcile_calls.append(name)
+                if isinstance(reconcile, Exception):
+                    raise reconcile
+                return reconcile
+            self.reconcile_playlist = reconcile_playlist
+
+    def update_playlist(self, name, tracks):
+        self.replace_calls.append(name)
+        return True
+
+
+def test_reconcile_success_does_not_fall_back():
+    c = _Client(reconcile=True)
+    assert _service()._reconcile_or_replace(c, 'P', []) is True
+    assert c.reconcile_calls == ['P']
+    assert c.replace_calls == []           # never recreated
+
+
+def test_reconcile_false_falls_back_to_replace():
+    c = _Client(reconcile=False)
+    assert _service()._reconcile_or_replace(c, 'P', []) is True
+    assert c.reconcile_calls == ['P']
+    assert c.replace_calls == ['P']        # fell back so the sync still happens
+
+
+def test_reconcile_exception_falls_back_to_replace():
+    c = _Client(reconcile=RuntimeError('boom'))
+    assert _service()._reconcile_or_replace(c, 'P', []) is True
+    assert c.reconcile_calls == ['P']
+    assert c.replace_calls == ['P']
+
+
+def test_client_without_reconcile_uses_replace():
+    c = _Client(reconcile=None)            # no reconcile_playlist attribute
+    assert not hasattr(c, 'reconcile_playlist')
+    assert _service()._reconcile_or_replace(c, 'P', []) is True
+    assert c.replace_calls == ['P']

tests/test_acoustid_skip_logic.py

@@ -185,6 +185,80 @@ def test_high_score_but_artist_mismatch_no_longer_skipped(verifier):
     assert result == VerificationResult.FAIL
 
 
+def test_low_fingerprint_score_never_skipped_same_script_artist(verifier):
+    """#797 guard — the #607 protection for a SAME-SCRIPT artist (Latin
+    'Yoko Takahashi' on both sides) with only a cross-script TITLE must
+    stay FAIL below the 0.95 floor. The #797 relaxation is keyed on the
+    ARTIST spanning scripts, which this case is NOT, so nothing changes
+    here. (Duplicates test_low_fingerprint_score_never_skipped's intent
+    explicitly against the new code path.)"""
+    _stub_lookup(verifier, recordings=[
+        {'title': '残酷な天使のテーゼ', 'artist': 'Yoko Takahashi'},
+    ], best_score=0.85)
+
+    result, _msg = verifier.verify_audio_file(
+        '/fake/path.flac',
+        'Zankoku na Tenshi no Theze',
+        'Yoko Takahashi',
+    )
+    assert result == VerificationResult.FAIL
+
+
+# ---------------------------------------------------------------------------
+# Issue #797 — non-English ARTIST whose name spans scripts
+# ---------------------------------------------------------------------------
+
+
+def test_cross_script_artist_confirmed_via_alias_skips_below_095(verifier):
+    """#797 headline: requested 'Joe Hisaishi' (romanized), AcoustID
+    returns the recording with the artist/title in their native kanji
+    ('久石譲'). The alias bridge confirms 久石譲 IS Joe Hisaishi, the
+    fingerprint is solid (0.85, above the 0.80 trust floor) but below
+    the old 0.95 language/script bar. Pre-#797 this FAILed and the
+    correct file was quarantined. Now it SKIPs."""
+    with patch(
+        'core.acoustid_verification._resolve_expected_artist_aliases',
+        return_value=['久石譲'],
+    ):
+        _stub_lookup(verifier, recordings=[
+            {'title': '風のとおり道', 'artist': '久石譲'},
+        ], best_score=0.85)
+
+        result, msg = verifier.verify_audio_file(
+            '/fake/path.flac',
+            'The Path of the Wind',
+            'Joe Hisaishi',
+        )
+    assert result == VerificationResult.SKIP
+    assert 'language/script' in msg.lower()
+
+
+def test_cross_script_artist_NOT_confirmed_still_fails(verifier):
+    """#797 tight scope: if the alias bridge can't confirm the artist
+    (lookup returns nothing), we have no positive evidence the kanji
+    artist IS the expected one — so the #797 relaxation must NOT fire.
+    The relaxation only rescues a CONFIRMED cross-script artist.
+
+    Constructed so best_rec is set (partial title overlap → non-zero
+    combined score) and the title stays under the strict threshold, so
+    the flow reaches the same skip-decision point the rescue lives at —
+    proving it doesn't fire without a confirmed artist."""
+    with patch(
+        'core.acoustid_verification._resolve_expected_artist_aliases',
+        return_value=[],
+    ):
+        _stub_lookup(verifier, recordings=[
+            {'title': 'Summer Night', 'artist': '久石譲'},
+        ], best_score=0.85)
+
+        result, _msg = verifier.verify_audio_file(
+            '/fake/path.flac',
+            'Summer',
+            'Joe Hisaishi',
+        )
+    assert result == VerificationResult.FAIL
+
+
 def test_old_loose_threshold_no_longer_fires_for_unrelated_titles(verifier):
     """Pin the negative case for the old loose threshold (title_sim
     >= 0.55). 'Crown' vs 'Crown of Thorns' had similarity around 0.6

tests/test_album_bundle.py

@@ -360,6 +360,40 @@ def test_copy_audio_files_atomically_creates_staging_dir(tmp_path: Path) -> None
     assert staging.exists()
 
 
+def test_copy_audio_files_atomically_keeps_source_by_default(tmp_path: Path) -> None:
+    """Default (torrent/usenet): originals stay put (client keeps seeding)."""
+    src = tmp_path / 'a.flac'
+    src.write_bytes(b'a')
+    staging = tmp_path / 'staging'
+    out = copy_audio_files_atomically([src], staging)
+    assert len(out) == 1
+    assert src.exists()                       # source retained
+
+
+def test_copy_audio_files_atomically_removes_source_when_requested(tmp_path: Path) -> None:
+    """#796: Soulseek path removes slskd's completed files once staged so they
+    don't pile up in the download folder."""
+    src_a = tmp_path / 'a.flac'; src_a.write_bytes(b'a')
+    src_c = tmp_path / 'c.flac'; src_c.write_bytes(b'c')
+    staging = tmp_path / 'staging'
+    out = copy_audio_files_atomically([src_a, src_c], staging, remove_source=True)
+    assert len(out) == 2                      # both staged
+    assert not src_a.exists() and not src_c.exists()   # sources removed
+    assert sorted(Path(p).name for p in out) == ['a.flac', 'c.flac']
+
+
+def test_copy_audio_files_atomically_keeps_source_when_copy_fails(tmp_path: Path) -> None:
+    """Data safety: a source whose copy FAILS must never be deleted, even with
+    remove_source=True."""
+    src_ok = tmp_path / 'ok.flac'; src_ok.write_bytes(b'ok')
+    src_missing = tmp_path / 'gone.flac'      # never created -> copy fails
+    staging = tmp_path / 'staging'
+    out = copy_audio_files_atomically([src_ok, src_missing], staging, remove_source=True)
+    assert len(out) == 1                       # only ok staged
+    assert not src_ok.exists()                 # staged source removed
+    assert not src_missing.exists()            # never existed (and not created)
+
+
 # ---------------------------------------------------------------------------
 # Config-driven poll cadence
 # ---------------------------------------------------------------------------

tests/test_canonical_manual_lock.py

@@ -0,0 +1,99 @@
+"""#758 — a manual album match pins (and LOCKS) the canonical album version, so
+re-resolution / the auto canonical job can't drag it back to the deluxe edition.
+
+Two seams:
+  - should_pin_manual_canonical (pure): when a manual match should pin canonical.
+  - set_album_canonical / get_album_canonical (DB): the lock can't be overwritten
+    by an auto write, but a new manual write still wins.
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+
+from core.metadata.canonical_version import (
+    CANONICAL_ALBUM_SOURCES,
+    should_pin_manual_canonical,
+)
+from database.music_database import MusicDatabase
+
+
+# ---------------------------------------------------------------------------
+# should_pin_manual_canonical — pure
+# ---------------------------------------------------------------------------
+
+@pytest.mark.parametrize('source', ['spotify', 'itunes', 'deezer', 'discogs', 'hydrabase'])
+def test_pins_album_on_recognised_source(source):
+    assert should_pin_manual_canonical('album', source) is True
+
+
+@pytest.mark.parametrize('entity', ['artist', 'track'])
+def test_does_not_pin_non_album(entity):
+    assert should_pin_manual_canonical(entity, 'spotify') is False
+
+
+@pytest.mark.parametrize('source', ['lastfm', 'genius', 'musicbrainz', 'audiodb', 'tidal'])
+def test_does_not_pin_source_canonical_cant_read(source):
+    # No album-version data the canonical tools read → nothing to pin.
+    assert should_pin_manual_canonical('album', source) is False
+
+
+def test_sources_stay_in_sync_with_album_id_columns():
+    # The set must mirror the canonical reader's column map; if a source is
+    # added there, this fails until CANONICAL_ALBUM_SOURCES is updated.
+    from core.library_reorganize import _ALBUM_ID_COLUMNS
+    assert CANONICAL_ALBUM_SOURCES == set(_ALBUM_ID_COLUMNS)
+
+
+# ---------------------------------------------------------------------------
+# set_album_canonical / get_album_canonical — the lock (DB)
+# ---------------------------------------------------------------------------
+
+def _insert_album(db, album_id):
+    conn = db._get_connection()
+    conn.execute("INSERT OR IGNORE INTO artists (id, name) VALUES ('ar1', 'Artist')")
+    conn.execute("INSERT INTO albums (id, artist_id, title) VALUES (?, 'ar1', 'Album')", (album_id,))
+    conn.commit()
+    conn.close()
+
+
+@pytest.fixture
+def db(tmp_path: Path) -> MusicDatabase:
+    d = MusicDatabase(database_path=str(tmp_path / "ml.db"))
+    _insert_album(d, 'al1')
+    return d
+
+
+def test_manual_lock_set_and_read(db):
+    assert db.set_album_canonical('al1', 'spotify', 'REG', 1.0, locked=True) is True
+    c = db.get_album_canonical('al1')
+    assert c['source'] == 'spotify' and c['album_id'] == 'REG' and c['locked'] is True
+
+
+def test_auto_cannot_overwrite_manual_lock(db):
+    db.set_album_canonical('al1', 'spotify', 'REG', 1.0, locked=True)
+    # The auto resolve job tries to re-pin the deluxe — must be refused.
+    assert db.set_album_canonical('al1', 'spotify', 'DELUXE', 0.9, locked=False) is False
+    c = db.get_album_canonical('al1')
+    assert c['album_id'] == 'REG' and c['locked'] is True  # unchanged
+
+
+def test_new_manual_match_overrides_existing_pin(db):
+    db.set_album_canonical('al1', 'spotify', 'OLD', 0.8, locked=False)  # auto pin
+    # User manually picks a different edition — manual always wins.
+    assert db.set_album_canonical('al1', 'itunes', 'NEW', 1.0, locked=True) is True
+    c = db.get_album_canonical('al1')
+    assert c['source'] == 'itunes' and c['album_id'] == 'NEW' and c['locked'] is True
+
+
+def test_auto_overwrites_auto(db):
+    db.set_album_canonical('al1', 'spotify', 'A', 0.8, locked=False)
+    assert db.set_album_canonical('al1', 'spotify', 'B', 0.9, locked=False) is True
+    assert db.get_album_canonical('al1')['album_id'] == 'B'
+
+
+def test_unresolved_album_returns_none(db):
+    _insert_album(db, 'al2')
+    assert db.get_album_canonical('al2') is None

tests/test_database_update_reconcile_hook.py

@@ -0,0 +1,66 @@
+"""The auto-reconcile must run as the FINAL scan phase — inside the worker's
+completion, BEFORE the 'finished' signal — so the scan's status stays
+'running' through it. That ordering is what makes automations (which poll for
+completion), the dashboard card, and the Tools page all treat the reconcile as
+part of the scan and wait for it, rather than seeing 'finished' early and
+missing the tail. These pin that contract on DatabaseUpdateWorker._emit_finished.
+"""
+
+from __future__ import annotations
+
+from core.database_update_worker import DatabaseUpdateWorker
+
+
+def _bare_worker():
+    # __new__ avoids the full media-client/config init; _emit_finished only
+    # touches self.callbacks + self.post_scan_hook.
+    w = DatabaseUpdateWorker.__new__(DatabaseUpdateWorker)
+    w.callbacks = {'finished': [], 'error': [], 'progress_updated': [],
+                   'phase_changed': [], 'artist_processed': []}
+    w.post_scan_hook = None
+    return w
+
+
+def test_post_scan_hook_runs_before_finished():
+    w = _bare_worker()
+    order = []
+    w.post_scan_hook = lambda worker: order.append('hook')
+    w.callbacks['finished'].append(lambda *a: order.append('finished'))
+    w._emit_finished(1, 2, 3, 4, 5)
+    assert order == ['hook', 'finished']  # reconcile happens inside the running window
+
+
+def test_finished_receives_original_args():
+    w = _bare_worker()
+    got = []
+    w.callbacks['finished'].append(lambda *a: got.append(a))
+    w._emit_finished(1, 2, 3, 4, 5)
+    assert got == [(1, 2, 3, 4, 5)]
+
+
+def test_no_hook_still_emits_finished():
+    # Backward-compatible: a worker with no hook signals finished exactly as before.
+    w = _bare_worker()
+    got = []
+    w.callbacks['finished'].append(lambda *a: got.append(a))
+    w._emit_finished(0, 0, 0, 0, 0)
+    assert got == [(0, 0, 0, 0, 0)]
+
+
+def test_hook_exception_never_blocks_finished():
+    # A reconcile failure must not strand the scan as perpetually 'running'.
+    w = _bare_worker()
+    fired = []
+    w.post_scan_hook = lambda worker: (_ for _ in ()).throw(RuntimeError("boom"))
+    w.callbacks['finished'].append(lambda *a: fired.append(a))
+    w._emit_finished(1, 1, 1, 1, 1)
+    assert fired == [(1, 1, 1, 1, 1)]
+
+
+def test_hook_receives_the_worker():
+    w = _bare_worker()
+    seen = []
+    w.post_scan_hook = lambda worker: seen.append(worker)
+    w.callbacks['finished'].append(lambda *a: None)
+    w._emit_finished(0, 0, 0, 0, 0)
+    assert seen == [w]

tests/test_dedupe_source_ids.py

@@ -0,0 +1,168 @@
+"""Tests for core/maintenance/dedupe_source_ids.py — the one-off repair for
+source ids that enrichment wrongly shared across multiple artists.
+
+Corruption = one source id on artists with DIFFERENT names. Legit duplicates =
+the SAME artist on two media servers, same name — must be left alone.
+"""
+
+from __future__ import annotations
+
+import pytest
+
+import database.music_database as mdb_mod
+from core.maintenance import dedupe_source_ids as dd
+from database.music_database import MusicDatabase
+
+
+@pytest.fixture
+def db(tmp_path):
+    return MusicDatabase(str(tmp_path / "music.db"))
+
+
+def _insert(db, *, artist_id, name, **extra):
+    cols = ["id", "name", "server_source"] + list(extra.keys())
+    vals = [artist_id, name, "plex"] + list(extra.values())
+    placeholders = ",".join("?" for _ in cols)
+    with db._get_connection() as conn:
+        conn.execute(
+            f"INSERT INTO artists ({','.join(cols)}) VALUES ({placeholders})", vals
+        )
+        conn.commit()
+
+
+def _get(db, artist_id, col):
+    with db._get_connection() as conn:
+        return conn.execute(f"SELECT {col} FROM artists WHERE id=?", (artist_id,)).fetchone()[0]
+
+
+# ---------------------------------------------------------------------------
+# Detection
+# ---------------------------------------------------------------------------
+
+def test_detects_different_name_cluster_as_corrupt(db):
+    _insert(db, artist_id="1", name="Kendrick Lamar", deezer_id="525046")
+    _insert(db, artist_id="2", name="Jorja Smith", deezer_id="525046")
+    _insert(db, artist_id="3", name="Vince Staples", deezer_id="525046")
+
+    clusters = dd.find_corrupt_clusters(db)
+    assert len(clusters) == 1
+    c = clusters[0]
+    assert c['source'] == 'deezer'
+    assert c['source_id'] == '525046'
+    assert {n for _, n in c['members']} == {"Kendrick Lamar", "Jorja Smith", "Vince Staples"}
+
+
+def test_same_name_duplicate_is_not_corrupt(db):
+    # Same artist on two servers — legit shared id, must be ignored.
+    _insert(db, artist_id="10", name="Radiohead", deezer_id="999")
+    _insert(db, artist_id="11", name="radiohead", deezer_id="999")  # case-insensitive
+    assert dd.find_corrupt_clusters(db) == []
+
+
+def test_unique_ids_are_not_corrupt(db):
+    _insert(db, artist_id="20", name="A", deezer_id="1")
+    _insert(db, artist_id="21", name="B", deezer_id="2")
+    assert dd.find_corrupt_clusters(db) == []
+
+
+def test_detects_corruption_across_multiple_sources(db):
+    _insert(db, artist_id="1", name="Kendrick", deezer_id="525046", spotify_artist_id="sp-x")
+    _insert(db, artist_id="2", name="Jorja", deezer_id="525046")
+    _insert(db, artist_id="3", name="Someone", spotify_artist_id="sp-x")
+    sources = {c['source'] for c in dd.find_corrupt_clusters(db)}
+    assert sources == {'deezer', 'spotify'}
+
+
+# ---------------------------------------------------------------------------
+# Repair
+# ---------------------------------------------------------------------------
+
+def test_dry_run_writes_nothing(db):
+    _insert(db, artist_id="1", name="Kendrick", deezer_id="525046", deezer_match_status="matched")
+    _insert(db, artist_id="2", name="Jorja", deezer_id="525046", deezer_match_status="matched")
+
+    report = dd.clear_corrupt_source_ids(db, dry_run=True)
+    assert report['dry_run'] is True
+    assert report['cluster_count'] == 1
+    assert report['artist_count'] == 2
+    assert report['by_source'] == {'deezer': 2}
+    # Nothing changed.
+    assert _get(db, "1", "deezer_id") == "525046"
+    assert _get(db, "2", "deezer_id") == "525046"
+
+
+def test_apply_clears_id_and_status_for_corrupt_rows(db):
+    _insert(db, artist_id="1", name="Kendrick", deezer_id="525046", deezer_match_status="matched")
+    _insert(db, artist_id="2", name="Jorja", deezer_id="525046", deezer_match_status="matched")
+
+    report = dd.clear_corrupt_source_ids(db, dry_run=False)
+    assert report['dry_run'] is False
+    assert report['artist_count'] == 2
+    # Both cleared so the (now name-checked) worker re-derives them.
+    for aid in ("1", "2"):
+        assert _get(db, aid, "deezer_id") is None
+        assert _get(db, aid, "deezer_match_status") is None
+
+
+def test_apply_leaves_legit_duplicates_untouched(db):
+    # Corrupt deezer cluster + a legit same-name spotify duplicate.
+    _insert(db, artist_id="1", name="Kendrick", deezer_id="525046")
+    _insert(db, artist_id="2", name="Jorja", deezer_id="525046")
+    _insert(db, artist_id="3", name="Radiohead", spotify_artist_id="rh", server_source="plex")
+    _insert(db, artist_id="4", name="Radiohead", spotify_artist_id="rh", server_source="jellyfin")
+
+    with db._get_connection() as conn:
+        conn.execute("UPDATE artists SET server_source='jellyfin' WHERE id='4'")
+        conn.commit()
+
+    dd.clear_corrupt_source_ids(db, dry_run=False)
+    # Corrupt deezer ids cleared…
+    assert _get(db, "1", "deezer_id") is None
+    assert _get(db, "2", "deezer_id") is None
+    # …legit same-name spotify duplicate preserved.
+    assert _get(db, "3", "spotify_artist_id") == "rh"
+    assert _get(db, "4", "spotify_artist_id") == "rh"
+
+
+def test_clean_library_is_a_noop(db):
+    _insert(db, artist_id="1", name="A", deezer_id="1")
+    _insert(db, artist_id="2", name="B", deezer_id="2")
+    report = dd.clear_corrupt_source_ids(db, dry_run=False)
+    assert report['cluster_count'] == 0
+    assert report['artist_count'] == 0
+
+
+# ---------------------------------------------------------------------------
+# The one-time startup migration (auto-repair for users who pull the fix)
+# ---------------------------------------------------------------------------
+
+def test_startup_migration_clears_shared_source_ids(tmp_path):
+    """The _source_id_dedupe_v1 migration in MusicDatabase init must clear
+    differently-named shared ids and leave same-name cross-server dups."""
+    path = str(tmp_path / "music.db")
+    db = MusicDatabase(path)  # first init creates the marker on an empty db
+
+    with db._get_connection() as conn:
+        conn.execute("INSERT INTO artists (id,name,server_source,deezer_id,deezer_match_status) "
+                     "VALUES ('1','Kendrick Lamar','plex','525046','matched')")
+        conn.execute("INSERT INTO artists (id,name,server_source,deezer_id,deezer_match_status) "
+                     "VALUES ('2','Jorja Smith','plex','525046','matched')")
+        # Legit same-name dup across two servers — must survive.
+        conn.execute("INSERT INTO artists (id,name,server_source,spotify_artist_id) "
+                     "VALUES ('3','Radiohead','plex','rh')")
+        conn.execute("INSERT INTO artists (id,name,server_source,spotify_artist_id) "
+                     "VALUES ('4','Radiohead','jellyfin','rh')")
+        conn.execute("DROP TABLE _source_id_dedupe_v1")
+        conn.commit()
+
+    # Force the one-time migration to run again.
+    mdb_mod._database_initialized_paths.clear()
+    MusicDatabase(path)
+
+    with db._get_connection() as conn:
+        k = conn.execute("SELECT deezer_id, deezer_match_status FROM artists WHERE id='1'").fetchone()
+        assert tuple(k) == (None, None)
+        assert conn.execute("SELECT deezer_id FROM artists WHERE id='2'").fetchone()[0] is None
+        rh = conn.execute("SELECT spotify_artist_id FROM artists WHERE id IN ('3','4')").fetchall()
+        assert all(r[0] == 'rh' for r in rh)
+        assert conn.execute("SELECT name FROM sqlite_master WHERE name='_source_id_dedupe_v1'").fetchone()

tests/test_deezer_worker_artist_id_guard.py

@@ -0,0 +1,76 @@
+"""Regression: Deezer enrichment must not overwrite an artist's deezer_id from a
+collaboration/compilation track whose primary artist is someone else.
+
+The Kendrick/Jorja bug: a track our library credits to Jorja Smith lives on
+Kendrick Lamar's curated "Black Panther" album. The album/track search resolves
+to that album, whose Deezer primary artist is Kendrick (id 525046). The old
+``_verify_artist_id`` "corrected" Jorja's deezer_id to 525046 with no name
+check — stamping one Deezer id across several unrelated artists, which later
+broke the artist-detail page (it matched the wrong library artist by id).
+
+The fix gates the correction on a name match between the result's primary
+artist and our parent artist.
+"""
+
+from __future__ import annotations
+
+from core.deezer_worker import DeezerWorker
+
+
+def _worker():
+    # Bypass __init__ — it wants real clients/db. We only exercise the pure
+    # _verify_artist_id / _name_matches / _normalize_name logic.
+    w = DeezerWorker.__new__(DeezerWorker)
+    w.name_similarity_threshold = 0.80
+    w._corrections = []
+    w._correct_artist_deezer_id = lambda item, cid: w._corrections.append((item['id'], cid))
+    return w
+
+
+def _item(artist_name, parent_deezer_id):
+    return {
+        'type': 'track', 'id': 1, 'name': 'Some Track',
+        'artist': artist_name, 'artist_deezer_id': parent_deezer_id,
+    }
+
+
+def test_no_correction_when_result_artist_name_differs():
+    # Jorja Smith (deezer 999) but the track resolved to Kendrick's album
+    # (Deezer artist 525046, 'Kendrick Lamar') → must NOT overwrite.
+    w = _worker()
+    w._verify_artist_id(_item('Jorja Smith', '999'), '525046', 'Kendrick Lamar')
+    assert w._corrections == []
+
+
+def test_correction_when_names_match():
+    # Same artist, stale/wrong stored id → legitimate correction proceeds.
+    w = _worker()
+    w._verify_artist_id(_item('Kendrick Lamar', '111'), '525046', 'Kendrick Lamar')
+    assert w._corrections == [(1, '525046')]
+
+
+def test_name_match_tolerates_minor_variation():
+    # Fuzzy match (feat. suffix / casing) still counts as the same artist.
+    w = _worker()
+    w._verify_artist_id(_item('Kendrick Lamar', '111'), '525046', 'KENDRICK LAMAR')
+    assert w._corrections == [(1, '525046')]
+
+
+def test_no_correction_when_ids_already_equal():
+    w = _worker()
+    w._verify_artist_id(_item('Whoever', '525046'), '525046', 'Anyone')
+    assert w._corrections == []
+
+
+def test_no_parent_id_is_noop():
+    w = _worker()
+    w._verify_artist_id(_item('X', None), '525046', 'Y')
+    assert w._corrections == []
+
+
+def test_missing_result_name_preserves_old_behavior():
+    # No artist name on the result → can't name-check; keep the original
+    # "trust the more specific album/track search" behavior.
+    w = _worker()
+    w._verify_artist_id(_item('Kendrick Lamar', '111'), '525046', None)
+    assert w._corrections == [(1, '525046')]

tests/test_embed_known_source_ids.py

@@ -0,0 +1,69 @@
+"""Seam test: embed_known_source_ids builds the right id_tags and routes them
+through the canonical frame writer (no API re-fetch)."""
+
+import sys
+import types
+from types import SimpleNamespace
+
+# Stub spotipy/config so core.metadata.source imports cleanly in tests.
+if 'spotipy' not in sys.modules:
+    sp = types.ModuleType('spotipy'); oa = types.ModuleType('spotipy.oauth2')
+    sp.Spotify = type('S', (), {}); oa.SpotifyOAuth = oa.SpotifyClientCredentials = type('O', (), {})
+    sp.oauth2 = oa; sys.modules['spotipy'] = sp; sys.modules['spotipy.oauth2'] = oa
+if 'config.settings' not in sys.modules:
+    cm = types.ModuleType('config'); sm = types.ModuleType('config.settings')
+
+    class _Cfg:
+        def get(self, k, d=None): return d
+        def get_active_media_server(self): return 'plex'
+    sm.config_manager = _Cfg(); cm.settings = sm
+    sys.modules['config'] = cm; sys.modules['config.settings'] = sm
+
+from core.metadata import source as src
+
+
+def test_builds_id_tags_from_flat_keys_and_calls_writer(monkeypatch):
+    captured = {}
+    monkeypatch.setattr(src, 'get_mutagen_symbols', lambda: SimpleNamespace())
+    monkeypatch.setattr(src, 'get_config_manager', lambda: SimpleNamespace(get=lambda k, d=None: d))
+
+    def _fake_write(audio, metadata, pp, cfg, symbols):
+        captured['id_tags'] = dict(pp['id_tags'])
+    monkeypatch.setattr(src, '_write_embedded_metadata', _fake_write)
+
+    meta = {
+        'spotify_track_id': 'sp_t', 'spotify_album_id': 'sp_a',
+        'itunes_track_id': 'it_t',
+        'musicbrainz_recording_id': 'mb_rec', 'musicbrainz_release_id': 'mb_rel',
+    }
+    written = src.embed_known_source_ids(object(), meta)
+
+    assert captured['id_tags']['SPOTIFY_TRACK_ID'] == 'sp_t'
+    assert captured['id_tags']['SPOTIFY_ALBUM_ID'] == 'sp_a'
+    assert captured['id_tags']['ITUNES_TRACK_ID'] == 'it_t'
+    assert captured['id_tags']['MUSICBRAINZ_RECORDING_ID'] == 'mb_rec'
+    assert captured['id_tags']['MUSICBRAINZ_RELEASE_ID'] == 'mb_rel'
+    assert set(written) >= {'SPOTIFY_TRACK_ID', 'MUSICBRAINZ_RECORDING_ID'}
+
+
+def test_no_ids_writes_nothing(monkeypatch):
+    called = {'n': 0}
+    monkeypatch.setattr(src, 'get_mutagen_symbols', lambda: SimpleNamespace())
+    monkeypatch.setattr(src, 'get_config_manager', lambda: SimpleNamespace(get=lambda k, d=None: d))
+    monkeypatch.setattr(src, '_write_embedded_metadata',
+                        lambda *a, **k: called.__setitem__('n', called['n'] + 1))
+    assert src.embed_known_source_ids(object(), {'title': 'x'}) == []
+    assert called['n'] == 0      # nothing to embed → writer never called
+
+
+def test_musicbrainz_gated_off(monkeypatch):
+    captured = {}
+    monkeypatch.setattr(src, 'get_mutagen_symbols', lambda: SimpleNamespace())
+    # mb embed disabled
+    monkeypatch.setattr(src, 'get_config_manager',
+                        lambda: SimpleNamespace(get=lambda k, d=None: False if k == 'musicbrainz.embed_tags' else d))
+    monkeypatch.setattr(src, '_write_embedded_metadata',
+                        lambda audio, m, pp, cfg, sym: captured.update(pp['id_tags']))
+    src.embed_known_source_ids(object(), {'spotify_track_id': 'sp', 'musicbrainz_recording_id': 'mb'})
+    assert 'SPOTIFY_TRACK_ID' in captured
+    assert 'MUSICBRAINZ_RECORDING_ID' not in captured   # gated off

tests/test_enrichment_artist_id_guard.py

@@ -0,0 +1,100 @@
+"""Regression: the album/track-driven 'artist id correction' in every
+enrichment worker that has it must NOT overwrite an artist's source id unless
+the result's artist name actually matches.
+
+This is the same Kendrick/Jorja bug fixed in the Deezer worker (see
+tests/test_deezer_worker_artist_id_guard.py), proven here to be closed in the
+three other workers that copy-pasted the pattern: AudioDB, Qobuz, Tidal.
+
+A track our library credits to Jorja Smith that lives on Kendrick's curated
+'Black Panther' album resolves to that album, whose primary artist is Kendrick.
+Without a name check, each worker would 'correct' Jorja's source id to
+Kendrick's — corrupting it (and sharing one id across unrelated artists).
+"""
+
+from __future__ import annotations
+
+from core.audiodb_worker import AudioDBWorker
+from core.qobuz_worker import QobuzWorker
+from core.tidal_worker import TidalWorker
+
+
+def _stub(cls, correct_attr):
+    """Build a bare worker instance (no __init__/clients) wired to record
+    corrections instead of writing to a db."""
+    w = cls.__new__(cls)
+    w.name_similarity_threshold = 0.80
+    w._corrections = []
+    setattr(w, correct_attr, lambda item, cid: w._corrections.append((item['id'], cid)))
+    return w
+
+
+def _item(artist_name, parent_id, id_key):
+    return {'type': 'track', 'id': 1, 'name': 'Some Track',
+            'artist': artist_name, id_key: parent_id}
+
+
+# --------------------------------------------------------------------------
+# AudioDB — _verify_artist_id(item, result_dict); name is result['strArtist'].
+# --------------------------------------------------------------------------
+
+def test_audiodb_skips_correction_on_name_mismatch():
+    w = _stub(AudioDBWorker, '_correct_artist_audiodb_id')
+    item = _item('Jorja Smith', '111', 'artist_audiodb_id')
+    w._verify_artist_id(item, {'idArtist': '999', 'strArtist': 'Kendrick Lamar'})
+    assert w._corrections == []
+
+
+def test_audiodb_corrects_on_name_match():
+    w = _stub(AudioDBWorker, '_correct_artist_audiodb_id')
+    item = _item('Kendrick Lamar', '111', 'artist_audiodb_id')
+    w._verify_artist_id(item, {'idArtist': '999', 'strArtist': 'Kendrick Lamar'})
+    assert w._corrections == [(1, '999')]
+
+
+# --------------------------------------------------------------------------
+# Qobuz — _verify_artist_id(item, result_artist_id, result_artist_name).
+# --------------------------------------------------------------------------
+
+def test_qobuz_skips_correction_on_name_mismatch():
+    w = _stub(QobuzWorker, '_correct_artist_qobuz_id')
+    item = _item('Jorja Smith', '111', 'artist_qobuz_id')
+    w._verify_artist_id(item, '999', 'Kendrick Lamar')
+    assert w._corrections == []
+
+
+def test_qobuz_corrects_on_name_match():
+    w = _stub(QobuzWorker, '_correct_artist_qobuz_id')
+    item = _item('Kendrick Lamar', '111', 'artist_qobuz_id')
+    w._verify_artist_id(item, '999', 'Kendrick Lamar')
+    assert w._corrections == [(1, '999')]
+
+
+# --------------------------------------------------------------------------
+# Tidal — _verify_artist_id(item, result_artist_id, result_artist_name).
+# --------------------------------------------------------------------------
+
+def test_tidal_skips_correction_on_name_mismatch():
+    w = _stub(TidalWorker, '_correct_artist_tidal_id')
+    item = _item('Jorja Smith', '111', 'artist_tidal_id')
+    w._verify_artist_id(item, '999', 'Kendrick Lamar')
+    assert w._corrections == []
+
+
+def test_tidal_corrects_on_name_match():
+    w = _stub(TidalWorker, '_correct_artist_tidal_id')
+    item = _item('Kendrick Lamar', '111', 'artist_tidal_id')
+    w._verify_artist_id(item, '999', 'Kendrick Lamar')
+    assert w._corrections == [(1, '999')]
+
+
+# --------------------------------------------------------------------------
+# Shared: a missing result name preserves the old "trust the search" behavior
+# (only the workers that pass an id+name — qobuz/tidal — exercise this path).
+# --------------------------------------------------------------------------
+
+def test_qobuz_missing_result_name_preserves_old_behavior():
+    w = _stub(QobuzWorker, '_correct_artist_qobuz_id')
+    item = _item('Kendrick Lamar', '111', 'artist_qobuz_id')
+    w._verify_artist_id(item, '999', None)
+    assert w._corrections == [(1, '999')]

tests/test_library_retag_job.py

@@ -0,0 +1,286 @@
+"""Seam tests for the Library Re-tag job scan + the apply handler.
+
+Injected fakes only — no metadata APIs, no real tag writes. A temp sqlite db
++ real (empty) track files exercise the orchestration: scan -> detailed
+finding, and finding -> per-track write payload.
+"""
+
+import sqlite3
+import sys
+import types
+from types import SimpleNamespace
+
+# Stub optional deps so the modules import in the test env.
+if 'spotipy' not in sys.modules:
+    sp = types.ModuleType('spotipy'); oa = types.ModuleType('spotipy.oauth2')
+    sp.Spotify = type('S', (), {}); oa.SpotifyOAuth = oa.SpotifyClientCredentials = type('O', (), {})
+    sp.oauth2 = oa; sys.modules['spotipy'] = sp; sys.modules['spotipy.oauth2'] = oa
+if 'config.settings' not in sys.modules:
+    cm = types.ModuleType('config'); sm = types.ModuleType('config.settings')
+
+    class _Cfg:
+        def get(self, k, d=None): return d
+        def get_active_media_server(self): return 'plex'
+    sm.config_manager = _Cfg(); cm.settings = sm
+    sys.modules['config'] = cm; sys.modules['config.settings'] = sm
+
+from core.repair_jobs import library_retag as lr
+
+
+def _db_with_album(path, track_file, current_title='Old Title'):
+    conn = sqlite3.connect(path)
+    c = conn.cursor()
+    c.execute("CREATE TABLE artists (id INTEGER PRIMARY KEY, name TEXT)")
+    c.execute("""CREATE TABLE albums (id INTEGER PRIMARY KEY, title TEXT, artist_id INTEGER,
+                 spotify_album_id TEXT, itunes_album_id TEXT, deezer_id TEXT, musicbrainz_release_id TEXT)""")
+    c.execute("""CREATE TABLE tracks (id INTEGER PRIMARY KEY, album_id INTEGER, title TEXT,
+                 track_number INTEGER, disc_number INTEGER, file_path TEXT)""")
+    c.execute("INSERT INTO artists (id, name) VALUES (1, 'Real Artist')")
+    c.execute("INSERT INTO albums (id, title, artist_id, spotify_album_id) VALUES (1, 'Real Album', 1, 'sp_alb')")
+    c.execute("INSERT INTO tracks (id, album_id, title, track_number, disc_number, file_path) VALUES (1, 1, ?, 1, 1, ?)",
+              (current_title, track_file))
+    conn.commit()
+    return conn
+
+
+def _context(conn, settings):
+    findings = []
+    return SimpleNamespace(
+        db=SimpleNamespace(_get_connection=lambda: conn),
+        config_manager=SimpleNamespace(get=lambda k, d=None: {'repair.jobs.library_retag.settings': settings}.get(k, d)),
+        check_stop=lambda: False, wait_if_paused=lambda: False,
+        update_progress=lambda *a, **k: None, report_progress=lambda *a, **k: None,
+        create_finding=lambda **kw: (findings.append(kw) or True),
+        findings=findings,
+    )
+
+
+_ALBUM_META = {'name': 'Real Album', 'artists': [{'name': 'Real Artist'}],
+               'year': '2021', 'genres': ['Rock'], 'total_tracks': 1,
+               'image_url': 'http://art/cover.jpg'}
+_SRC_TRACKS = [{'name': 'Real Title', 'track_number': 1, 'disc_number': 1, 'id': 'sp_trk'}]
+
+
+def _patch_source(monkeypatch, current_tags):
+    monkeypatch.setattr(lr, 'get_album_for_source', lambda s, i: _ALBUM_META)
+    monkeypatch.setattr(lr, 'get_album_tracks_for_source', lambda s, i: list(_SRC_TRACKS))
+    monkeypatch.setattr(lr, '_read_current_tags', lambda p: dict(current_tags))
+
+
+def test_scan_creates_detailed_finding(tmp_path, monkeypatch):
+    track = tmp_path / 'track.flac'; track.write_bytes(b'')
+    conn = _db_with_album(str(tmp_path / 'm.db'), str(track), current_title='Old Title')
+    ctx = _context(conn, {'mode': 'overwrite', 'cover_art': 'replace', 'source': 'spotify'})
+    _patch_source(monkeypatch, {
+        'title': 'Old Title', 'album_artist': 'Real Artist', 'album': 'Real Album',
+        'year': '2021', 'genre': 'Rock', 'track_number': 1, 'disc_number': 1,
+    })
+
+    result = lr.LibraryRetagJob().scan(ctx)
+
+    assert result.findings_created == 1
+    d = ctx.findings[0]['details']
+    assert ctx.findings[0]['finding_type'] == 'library_retag'
+    assert d['source'] == 'spotify'
+    assert d['cover_action'] == 'replace'
+    tp = d['tracks'][0]
+    assert tp['changes']['title'] == {'old': 'Old Title', 'new': 'Real Title'}
+    # source ids stamped onto the write payload
+    assert tp['db_data']['spotify_album_id'] == 'sp_alb'
+    assert tp['db_data']['spotify_track_id'] == 'sp_trk'
+    assert tp['db_data']['title'] == 'Real Title'
+
+
+def test_scan_dry_run_off_auto_applies_no_finding(tmp_path, monkeypatch):
+    """dry_run=False: scan applies in place (auto_fixed) and creates NO finding."""
+    track = tmp_path / 'track.flac'; track.write_bytes(b'')
+    conn = _db_with_album(str(tmp_path / 'm.db'), str(track), current_title='Old Title')
+    ctx = _context(conn, {'mode': 'overwrite', 'cover_art': 'skip', 'source': 'spotify', 'dry_run': False})
+    _patch_source(monkeypatch, {
+        'title': 'Old Title', 'album_artist': 'Real Artist', 'album': 'Real Album',
+        'year': '2021', 'genre': 'Rock', 'track_number': 1, 'disc_number': 1,
+    })
+    writes = []
+    monkeypatch.setattr('core.tag_writer.write_tags_to_file',
+                        lambda fp, db_data, **k: writes.append(db_data) or {'success': True})
+
+    result = lr.LibraryRetagJob().scan(ctx)
+
+    assert ctx.findings == []                 # no finding in apply mode
+    assert result.auto_fixed == 1
+    assert writes and writes[0]['title'] == 'Real Title'   # actually wrote
+
+
+def test_scan_prefers_configured_cover_art_source(tmp_path, monkeypatch):
+    """Sokhi's request: when cover-art sources are configured, the re-tag pulls
+    art from them (select_preferred_art_url) instead of the matched source's
+    album image — so changing sources + 'replace' re-downloads fresh covers."""
+    track = tmp_path / 'track.flac'; track.write_bytes(b'')
+    conn = _db_with_album(str(tmp_path / 'm.db'), str(track), current_title='Old Title')
+    ctx = _context(conn, {'mode': 'overwrite', 'cover_art': 'replace', 'source': 'spotify'})
+    _patch_source(monkeypatch, {
+        'title': 'Old Title', 'album_artist': 'Real Artist', 'album': 'Real Album',
+        'year': '2021', 'genre': 'Rock', 'track_number': 1, 'disc_number': 1,
+    })
+    monkeypatch.setattr('core.metadata.art_lookup.select_preferred_art_url',
+                        lambda artist, album, meta, order, **k: 'http://itunes/big-cover.jpg')
+
+    result = lr.LibraryRetagJob().scan(ctx)
+
+    assert result.findings_created == 1
+    d = ctx.findings[0]['details']
+    assert d['cover_url'] == 'http://itunes/big-cover.jpg'   # configured source won
+    assert d['cover_action'] == 'replace'
+
+
+def test_scan_falls_back_to_source_image_when_no_configured_art(tmp_path, monkeypatch):
+    """Non-breaking: with no configured cover-art order, keep using the matched
+    source's album image (select_preferred_art_url returns None)."""
+    track = tmp_path / 'track.flac'; track.write_bytes(b'')
+    conn = _db_with_album(str(tmp_path / 'm.db'), str(track), current_title='Old Title')
+    ctx = _context(conn, {'mode': 'overwrite', 'cover_art': 'replace', 'source': 'spotify'})
+    _patch_source(monkeypatch, {
+        'title': 'Old Title', 'album_artist': 'Real Artist', 'album': 'Real Album',
+        'year': '2021', 'genre': 'Rock', 'track_number': 1, 'disc_number': 1,
+    })
+    monkeypatch.setattr('core.metadata.art_lookup.select_preferred_art_url',
+                        lambda *a, **k: None)
+
+    result = lr.LibraryRetagJob().scan(ctx)
+    d = ctx.findings[0]['details']
+    assert d['cover_url'] == 'http://art/cover.jpg'   # _ALBUM_META['image_url']
+
+
+def test_scan_full_depth_attaches_full_meta_to_finding(tmp_path, monkeypatch):
+    """depth=full: each track plan carries a full_meta dict (title/album/artist +
+    source ids) for the enrichment cascade, and details record the depth."""
+    track = tmp_path / 'track.flac'; track.write_bytes(b'')
+    conn = _db_with_album(str(tmp_path / 'm.db'), str(track), current_title='Old Title')
+    ctx = _context(conn, {'mode': 'overwrite', 'cover_art': 'skip', 'source': 'spotify', 'depth': 'full'})
+    _patch_source(monkeypatch, {
+        'title': 'Old Title', 'album_artist': 'Real Artist', 'album': 'Real Album',
+        'year': '2021', 'genre': 'Rock', 'track_number': 1, 'disc_number': 1,
+    })
+
+    result = lr.LibraryRetagJob().scan(ctx)
+
+    assert result.findings_created == 1
+    d = ctx.findings[0]['details']
+    assert d['depth'] == 'full'
+    fm = d['tracks'][0]['full_meta']
+    assert fm['title'] == 'Real Title'
+    assert fm['album'] == 'Real Album'
+    assert fm['album_artist'] == 'Real Artist'
+    assert fm['spotify_album_id'] == 'sp_alb'
+    assert fm['spotify_track_id'] == 'sp_trk'
+
+
+def test_scan_full_depth_auto_apply_runs_enrich(tmp_path, monkeypatch):
+    """depth=full + dry_run off: after the light write, the full enrichment
+    cascade runs once per written track."""
+    track = tmp_path / 'track.flac'; track.write_bytes(b'')
+    conn = _db_with_album(str(tmp_path / 'm.db'), str(track), current_title='Old Title')
+    ctx = _context(conn, {'mode': 'overwrite', 'cover_art': 'skip', 'source': 'spotify',
+                          'depth': 'full', 'dry_run': False})
+    _patch_source(monkeypatch, {
+        'title': 'Old Title', 'album_artist': 'Real Artist', 'album': 'Real Album',
+        'year': '2021', 'genre': 'Rock', 'track_number': 1, 'disc_number': 1,
+    })
+    monkeypatch.setattr('core.tag_writer.write_tags_to_file',
+                        lambda fp, db_data, **k: {'success': True})
+    enriched = []
+    monkeypatch.setattr(lr, '_run_full_enrich',
+                        lambda fp, meta: enriched.append((fp, meta)) or True)
+
+    result = lr.LibraryRetagJob().scan(ctx)
+
+    assert result.auto_fixed == 1
+    assert len(enriched) == 1
+    assert enriched[0][1]['spotify_track_id'] == 'sp_trk'
+
+
+def test_scan_light_depth_does_not_run_enrich(tmp_path, monkeypatch):
+    """depth=light (default): no full_meta, enrichment cascade never invoked."""
+    track = tmp_path / 'track.flac'; track.write_bytes(b'')
+    conn = _db_with_album(str(tmp_path / 'm.db'), str(track), current_title='Old Title')
+    ctx = _context(conn, {'mode': 'overwrite', 'cover_art': 'skip', 'source': 'spotify',
+                          'dry_run': False})  # depth defaults to light
+    _patch_source(monkeypatch, {
+        'title': 'Old Title', 'album_artist': 'Real Artist', 'album': 'Real Album',
+        'year': '2021', 'genre': 'Rock', 'track_number': 1, 'disc_number': 1,
+    })
+    monkeypatch.setattr('core.tag_writer.write_tags_to_file',
+                        lambda fp, db_data, **k: {'success': True})
+    enriched = []
+    monkeypatch.setattr(lr, '_run_full_enrich',
+                        lambda fp, meta: enriched.append(fp) or True)
+
+    lr.LibraryRetagJob().scan(ctx)
+    assert enriched == []
+
+
+def test_scan_skips_album_already_correct(tmp_path, monkeypatch):
+    track = tmp_path / 'track.flac'; track.write_bytes(b'')
+    conn = _db_with_album(str(tmp_path / 'm.db'), str(track), current_title='Real Title')
+    # cover skipped + tags already match → nothing to do
+    ctx = _context(conn, {'mode': 'overwrite', 'cover_art': 'skip', 'source': 'spotify'})
+    _patch_source(monkeypatch, {
+        'title': 'Real Title', 'album_artist': 'Real Artist', 'album': 'Real Album',
+        'year': '2021', 'genre': 'Rock', 'track_number': 1, 'disc_number': 1,
+    })
+
+    result = lr.LibraryRetagJob().scan(ctx)
+    assert result.findings_created == 0
+    assert ctx.findings == []
+    assert result.skipped >= 1
+
+
+def test_add_source_ids_maps_per_source():
+    db = {}
+    lr._add_source_ids(db, 'spotify', 'AL', {'id': 'TR'})
+    assert db == {'spotify_album_id': 'AL', 'spotify_track_id': 'TR'}
+    db2 = {}
+    lr._add_source_ids(db2, 'musicbrainz', 'REL', {'id': 'REC'})
+    assert db2 == {'musicbrainz_release_id': 'REL', 'musicbrainz_recording_id': 'REC'}
+
+
+# ── apply handler ──
+
+def test_fix_library_retag_writes_each_track(tmp_path, monkeypatch):
+    import core.repair_worker as rw
+    track = tmp_path / 'a.flac'; track.write_bytes(b'')
+
+    worker = rw.RepairWorker.__new__(rw.RepairWorker)
+    worker.db = SimpleNamespace()
+    worker._config_manager = SimpleNamespace(get=lambda k, d=None: d)
+    worker.transfer_folder = str(tmp_path)
+
+    monkeypatch.setattr(rw, '_resolve_file_path', lambda p, *a, **k: p)
+    writes = []
+    monkeypatch.setattr('core.tag_writer.write_tags_to_file',
+                        lambda fp, db_data, **k: writes.append((fp, db_data)) or {'success': True})
+
+    details = {
+        'tracks': [{'file_path': str(track), 'db_data': {'title': 'Real Title', 'spotify_track_id': 'sp_trk'}}],
+        'cover_action': None, 'cover_url': None,
+    }
+    res = worker._fix_library_retag('album', '1', None, details)
+    assert res['success'] is True
+    assert res['written'] == 1
+    assert writes[0][1]['title'] == 'Real Title'
+    assert writes[0][1]['spotify_track_id'] == 'sp_trk'
+
+
+def test_fix_library_retag_counts_unreachable(tmp_path, monkeypatch):
+    import core.repair_worker as rw
+    worker = rw.RepairWorker.__new__(rw.RepairWorker)
+    worker.db = SimpleNamespace()
+    worker._config_manager = SimpleNamespace(get=lambda k, d=None: d)
+    worker.transfer_folder = str(tmp_path)
+    monkeypatch.setattr(rw, '_resolve_file_path', lambda p, *a, **k: p)
+    monkeypatch.setattr('core.tag_writer.write_tags_to_file', lambda *a, **k: {'success': True})
+
+    details = {'tracks': [{'file_path': str(tmp_path / 'missing.flac'), 'db_data': {'title': 'x'}}],
+               'cover_action': None, 'cover_url': None}
+    res = worker._fix_library_retag('album', '1', None, details)
+    assert res['success'] is False        # nothing written (file missing)

tests/test_lyrics_reembed_from_sidecar.py

@@ -168,53 +168,3 @@ def test_no_sidecar_falls_through_to_lrclib(fake_audio_file):
     assert os.path.exists(lrc)
     # And USLT was embedded
     client._embed_lyrics.assert_called_once()
-
-
-# ──────────────────────────────────────────────────────────────────────
-# RetagDeps integration — generate_lrc_file is now wired
-# ──────────────────────────────────────────────────────────────────────
-
-def test_retagdeps_accepts_generate_lrc_file_field():
-    from core.library.retag import RetagDeps
-
-    # Mock the required + optional deps with do-nothing callables
-    deps = RetagDeps(
-        config_manager=MagicMock(),
-        retag_lock=MagicMock(),
-        spotify_client=MagicMock(),
-        get_audio_quality_string=lambda *a: '',
-        enhance_file_metadata=lambda *a: True,
-        build_final_path_for_track=lambda *a: ('', ''),
-        safe_move_file=lambda *a: None,
-        cleanup_empty_directories=lambda *a: None,
-        download_cover_art=lambda *a: None,
-        docker_resolve_path=lambda x: x,
-        _get_retag_state=lambda: {},
-        _set_retag_state=lambda v: None,
-        get_database=lambda: MagicMock(),
-        generate_lrc_file=lambda *a: True,
-    )
-    assert callable(deps.generate_lrc_file)
-
-
-def test_retagdeps_generate_lrc_file_optional_for_backward_compat():
-    """Tests that built RetagDeps without the new field don't break."""
-    from core.library.retag import RetagDeps
-
-    deps = RetagDeps(
-        config_manager=MagicMock(),
-        retag_lock=MagicMock(),
-        spotify_client=MagicMock(),
-        get_audio_quality_string=lambda *a: '',
-        enhance_file_metadata=lambda *a: True,
-        build_final_path_for_track=lambda *a: ('', ''),
-        safe_move_file=lambda *a: None,
-        cleanup_empty_directories=lambda *a: None,
-        download_cover_art=lambda *a: None,
-        docker_resolve_path=lambda x: x,
-        _get_retag_state=lambda: {},
-        _set_retag_state=lambda v: None,
-        get_database=lambda: MagicMock(),
-    )
-    # Field defaults to None — no crash on construction.
-    assert deps.generate_lrc_file is None

tests/test_manual_library_match.py

@@ -90,6 +90,34 @@ def test_save_upserts_existing(db):
     assert row["source_title"] == "Updated"
 
 
+def test_save_persists_library_file_path(db):
+    """#787 durability: the file path is stored so a manual match can be
+    re-resolved after a rescan re-keys the track."""
+    ok = db.save_manual_library_match(1, "spotify", "track-abc", 42,
+                                       library_file_path="/music/Artist/Album/01.flac")
+    assert ok is True
+    row = db.get_manual_library_match(1, "spotify", "track-abc")
+    assert row["library_file_path"] == "/music/Artist/Album/01.flac"
+
+
+def test_find_track_id_by_file_path(db):
+    """Re-resolution primitive: locate the current tracks.id for a file path
+    (exact, then basename fallback)."""
+    with db._get_connection() as conn:
+        conn.execute("PRAGMA foreign_keys=OFF")
+        conn.execute(
+            "INSERT INTO tracks (id, album_id, artist_id, title, file_path) VALUES (?, ?, ?, ?, ?)",
+            ("7777", 1, 1, "Track", "/music/Artist/Album/01.flac"),
+        )
+    # Exact path
+    assert db.find_track_id_by_file_path("/music/Artist/Album/01.flac") == "7777"
+    # Basename fallback (server vs local path shape)
+    assert db.find_track_id_by_file_path("/different/root/01.flac") == "7777"
+    # Unknown file → None
+    assert db.find_track_id_by_file_path("/music/nope.flac") is None
+    assert db.find_track_id_by_file_path("") is None
+
+
 def test_delete_by_id(db):
     db.save_manual_library_match(1, "spotify", "track-abc", 42)
     row = db.get_manual_library_match(1, "spotify", "track-abc")

tests/test_missing_cover_art.py

@@ -162,6 +162,37 @@ def test_missing_cover_art_prefers_explicit_source_over_primary(monkeypatch):
     assert context.findings[0]['details']['found_artwork_url'] == 'https://img/spotify-direct'
 
 
+def test_missing_cover_art_uses_configured_art_sources(monkeypatch):
+    """When cover-art sources are configured (album_art_order), the Filler pulls
+    art from them and skips the metadata source-priority loop — same 'cover art
+    sources' notion the Re-tag job and post-process embed honor."""
+    conn = _make_db((1, 'Album', 1, '', 'sp-album', 'it-album', 'dz-album', 'dg-album', 'hy-album'))
+    settings = {
+        'repair.jobs.missing_cover_art.settings': {},
+        'metadata_enhancement.album_art_order': ['itunes', 'deezer'],
+    }
+    findings = []
+    context = SimpleNamespace(
+        db=SimpleNamespace(_get_connection=lambda: conn),
+        config_manager=SimpleNamespace(get=lambda key, default=None: settings.get(key, default)),
+        check_stop=lambda: False, wait_if_paused=lambda: False,
+        update_progress=lambda *a, **k: None, report_progress=lambda *a, **k: None,
+        create_finding=lambda **kw: (findings.append(kw) or True),
+        findings=findings,
+    )
+    monkeypatch.setattr(mca, 'get_primary_source', lambda: 'spotify')
+    consulted = []
+    monkeypatch.setattr(mca, 'get_client_for_source', lambda s: consulted.append(s) or _FakeClient())
+    monkeypatch.setattr('core.metadata.art_lookup.select_preferred_art_url',
+                        lambda artist, album, meta, order, **k: 'https://configured/art.jpg')
+
+    result = mca.MissingCoverArtJob().scan(context)
+
+    assert result.findings_created == 1
+    assert findings[0]['details']['found_artwork_url'] == 'https://configured/art.jpg'
+    assert consulted == []  # source-priority loop skipped when configured art wins
+
+
 def test_missing_cover_art_uses_primary_when_prefer_unset(monkeypatch):
     conn = _make_db((1, 'Album', 1, '', None, None, None, None, None))
     context = _make_context(conn)

tests/test_playlist_edit.py

@@ -2,7 +2,12 @@
 
 from __future__ import annotations
 
-from core.sync.playlist_edit import plan_playlist_add, remove_one_occurrence
+from core.sync.playlist_edit import (
+    normalize_sync_mode,
+    plan_playlist_add,
+    plan_playlist_reconcile,
+    remove_one_occurrence,
+)
 
 
 # ── plan_playlist_add: link must not duplicate ────────────────────────────
@@ -78,3 +83,72 @@ def test_remove_single_occurrence():
 def test_remove_stringifies():
     new_ids, removed = remove_one_occurrence([1, 2, 2, 3], 2)
     assert removed and new_ids == ["1", "2", "3"]
+
+
+# ── plan_playlist_reconcile: in-place delta (#792) ────────────────────────
+
+def test_reconcile_adds_new_keeps_existing():
+    # 4-track playlist + a 5th in source → add only the 5th, remove nothing.
+    plan = plan_playlist_reconcile(['a', 'b', 'c', 'd'], ['a', 'b', 'c', 'd', 'e'])
+    assert plan == {'add': ['e'], 'remove': []}
+
+
+def test_reconcile_removes_gone():
+    # Source dropped 'b' → remove it, add nothing.
+    plan = plan_playlist_reconcile(['a', 'b', 'c'], ['a', 'c'])
+    assert plan == {'add': [], 'remove': ['b']}
+
+
+def test_reconcile_add_and_remove_together():
+    plan = plan_playlist_reconcile(['a', 'b', 'c'], ['a', 'c', 'd', 'e'])
+    assert plan['add'] == ['d', 'e']       # desired order preserved
+    assert plan['remove'] == ['b']
+
+
+def test_reconcile_noop_when_identical():
+    assert plan_playlist_reconcile(['a', 'b'], ['a', 'b']) == {'add': [], 'remove': []}
+
+
+def test_reconcile_empty_desired_removes_all():
+    assert plan_playlist_reconcile(['a', 'b'], []) == {'add': [], 'remove': ['a', 'b']}
+
+
+def test_reconcile_empty_current_adds_all():
+    assert plan_playlist_reconcile([], ['a', 'b']) == {'add': ['a', 'b'], 'remove': []}
+
+
+def test_reconcile_stringifies_ids():
+    plan = plan_playlist_reconcile([1, 2], [2, 3])
+    assert plan == {'add': ['3'], 'remove': ['1']}
+
+
+def test_reconcile_duplicate_still_desired_not_removed():
+    # 'a' appears twice and is still desired → never queued for removal;
+    # a gone id is listed once even if it had duplicates.
+    plan = plan_playlist_reconcile(['a', 'a', 'b', 'b'], ['a'])
+    assert plan == {'add': [], 'remove': ['b']}
+
+
+# ── normalize_sync_mode: reconcile must survive resolution (#792 regression) ──
+
+def test_normalize_keeps_reconcile_from_config():
+    # The bug: a validation list omitting 'reconcile' downgraded the configured
+    # setting to 'replace'. No per-request override → configured value wins.
+    assert normalize_sync_mode(None, 'reconcile') == 'reconcile'
+    assert normalize_sync_mode('', 'reconcile') == 'reconcile'
+
+
+def test_normalize_request_overrides_config():
+    assert normalize_sync_mode('append', 'reconcile') == 'append'
+    assert normalize_sync_mode('reconcile', 'replace') == 'reconcile'
+
+
+def test_normalize_falls_back_for_unknown():
+    assert normalize_sync_mode('bogus', 'replace') == 'replace'
+    assert normalize_sync_mode(None, None) == 'replace'
+    assert normalize_sync_mode(None, 'also-bogus') == 'replace'
+
+
+def test_normalize_all_real_modes_pass_through():
+    for m in ('replace', 'append', 'reconcile'):
+        assert normalize_sync_mode(m, 'replace') == m

tests/test_retag_planner.py

@@ -0,0 +1,114 @@
+"""Unit tests for the library re-tag planner (pure match + diff + payload)."""
+
+from __future__ import annotations
+
+from core.library import retag_planner as rp
+
+
+# ── track matching ──
+
+def test_match_by_disc_and_track_number():
+    src = [
+        {'name': 'A', 'track_number': 1, 'disc_number': 1},
+        {'name': 'B', 'track_number': 2, 'disc_number': 1},
+    ]
+    lib = [
+        {'title': 'wrong title', 'track_number': 2, 'disc_number': 1},
+        {'title': 'whatever', 'track_number': 1, 'disc_number': 1},
+    ]
+    pairs = rp.match_source_tracks(src, lib)
+    assert pairs[0][1]['name'] == 'B'   # lib track #2 → source B
+    assert pairs[1][1]['name'] == 'A'
+
+
+def test_match_by_title_when_no_track_number():
+    src = [{'name': 'Bohemian Rhapsody', 'track_number': 1, 'disc_number': 1}]
+    lib = [{'title': 'Bohemian Rhapsody (Remastered)', 'track_number': None, 'disc_number': 1}]
+    pairs = rp.match_source_tracks(src, lib)
+    assert pairs[0][1]['name'] == 'Bohemian Rhapsody'
+
+
+def test_unmatched_library_track_is_none():
+    src = [{'name': 'A', 'track_number': 1, 'disc_number': 1}]
+    lib = [{'title': 'Completely Different', 'track_number': 9, 'disc_number': 1}]
+    pairs = rp.match_source_tracks(src, lib)
+    assert pairs[0][1] is None
+
+
+def test_source_track_consumed_once():
+    src = [{'name': 'A', 'track_number': 1, 'disc_number': 1}]
+    lib = [
+        {'title': 'A', 'track_number': 1, 'disc_number': 1},
+        {'title': 'A again', 'track_number': 1, 'disc_number': 1},
+    ]
+    pairs = rp.match_source_tracks(src, lib)
+    assert pairs[0][1] is not None
+    assert pairs[1][1] is None          # the one source track was already used
+
+
+# ── per-track diff (overwrite) ──
+
+ALBUM = {'name': 'Real Album', 'artists': [{'name': 'Real Artist'}],
+         'year': '2021-05-01', 'genres': ['Rock', 'Indie'], 'total_tracks': 10}
+SRC = {'name': 'Real Title', 'track_number': 3, 'disc_number': 1,
+       'artists': [{'name': 'Real Artist'}]}
+
+
+def test_overwrite_reports_changed_fields_only():
+    current = {'title': 'Old Title', 'album_artist': 'Real Artist',
+               'album': 'Real Album', 'year': '2021', 'genre': 'Rock, Indie',
+               'track_number': 3, 'disc_number': 1}
+    plan = rp.plan_track(current, SRC, ALBUM, mode=rp.MODE_OVERWRITE)
+    # Only the title differs; everything else already matches → single change.
+    assert set(plan['changes']) == {'title'}
+    assert plan['changes']['title'] == {'old': 'Old Title', 'new': 'Real Title'}
+    assert plan['db_data'].get('title') == 'Real Title'
+    # Unchanged fields must NOT be in the write payload.
+    assert 'album_title' not in plan['db_data']
+
+
+def test_overwrite_writes_album_artist_via_artist_name_key():
+    current = {'title': 'Real Title', 'album_artist': 'WRONG Artist',
+               'album': 'Real Album', 'year': '2021', 'genre': 'Rock, Indie',
+               'track_number': 3, 'disc_number': 1}
+    plan = rp.plan_track(current, SRC, ALBUM, mode=rp.MODE_OVERWRITE)
+    assert plan['changes']['artist'] == {'old': 'WRONG Artist', 'new': 'Real Artist'}
+    assert plan['db_data']['artist_name'] == 'Real Artist'      # writer uses artist_name = album artist
+
+
+def test_track_number_write_carries_track_count():
+    current = {'title': 'Real Title', 'album_artist': 'Real Artist', 'album': 'Real Album',
+               'year': '2021', 'genre': 'Rock, Indie', 'track_number': 99, 'disc_number': 1}
+    plan = rp.plan_track(current, SRC, ALBUM, mode=rp.MODE_OVERWRITE)
+    assert plan['db_data']['track_number'] == 3
+    assert plan['db_data']['track_count'] == 10                 # carried alongside
+
+
+def test_no_changes_when_everything_matches():
+    current = {'title': 'Real Title', 'album_artist': 'Real Artist', 'album': 'Real Album',
+               'year': '2021', 'genre': 'Rock, Indie', 'track_number': 3, 'disc_number': 1}
+    plan = rp.plan_track(current, SRC, ALBUM, mode=rp.MODE_OVERWRITE)
+    assert plan['changes'] == {}
+    assert plan['db_data'] == {}
+
+
+def test_source_blank_field_never_written():
+    album = {'name': 'Real Album', 'artists': [{'name': 'Real Artist'}]}  # no year/genres
+    current = {'title': 'Real Title', 'album_artist': 'Real Artist', 'album': 'Real Album',
+               'year': '', 'genre': '', 'track_number': 3, 'disc_number': 1}
+    plan = rp.plan_track(current, SRC, album, mode=rp.MODE_OVERWRITE)
+    assert 'year' not in plan['changes'] and 'year' not in plan['db_data']
+    assert 'genres' not in plan['db_data']
+
+
+# ── fill-missing mode ──
+
+def test_fill_missing_only_writes_blanks():
+    current = {'title': 'Keep My Title', 'album_artist': '', 'album': 'Real Album',
+               'year': '', 'genre': 'Rock, Indie', 'track_number': 3, 'disc_number': 1}
+    plan = rp.plan_track(current, SRC, ALBUM, mode=rp.MODE_FILL_MISSING)
+    # title is present (kept), artist + year are blank (filled). genre present (kept).
+    assert set(plan['changes']) == {'artist', 'year'}
+    assert 'title' not in plan['db_data']            # not overwritten in fill-missing
+    assert plan['db_data']['artist_name'] == 'Real Artist'
+    assert plan['db_data']['year'] == '2021'

tests/test_soulseek_album_fallback.py

@@ -83,7 +83,7 @@ def test_healthy_folder_does_not_fall_back():
     # True. Patch the atomic copy to echo the completed paths through.
     from pathlib import Path
     completed = [Path("/staged/01.flac"), Path("/staged/02.flac")]
-    with patch("core.soulseek_client.copy_audio_files_atomically", lambda files, dest: list(files)):
+    with patch("core.soulseek_client.copy_audio_files_atomically", lambda files, dest, **kw: list(files)):
         stub = _Stub(completed)
         with patch("core.soulseek_client.run_async", lambda x: x):
             result = SoulseekClient.download_album_to_staging(

tests/test_spotify_free_metadata.py

@@ -0,0 +1,224 @@
+"""Tests for core/spotify_free_metadata.py — the no-creds Spotify fallback.
+
+Pure-unit only: the live SpotipyFree calls hit the network and can't run in CI,
+but the two things that actually need pinning are pure — the activation gate and
+the artist normalizer (the one shape SpotipyFree returns raw). Fixtures below
+are trimmed from real captured responses (2026-06).
+"""
+
+from __future__ import annotations
+
+from core.spotify_free_metadata import (
+    normalize_artist,
+    should_block_rate_limited_resume,
+    should_offer_spotify_metadata,
+    should_use_free_fallback,
+    spotify_free_installed,
+)
+
+
+# ---------------------------------------------------------------------------
+# should_block_rate_limited_resume — the worker resume guard
+# ---------------------------------------------------------------------------
+
+def test_resume_blocked_when_rate_limited_and_nothing_serves():
+    # Plain auth, no free: resuming during a ban would just sleep → block.
+    assert should_block_rate_limited_resume(rate_limited=True, metadata_available=False) is True
+
+
+def test_resume_allowed_when_free_can_bridge():
+    # Rate-limited but free is available (metadata_available True during a ban
+    # because is_spotify_authenticated() is False while banned) → allow resume,
+    # the worker bridges via free.
+    assert should_block_rate_limited_resume(rate_limited=True, metadata_available=True) is False
+
+
+def test_resume_never_blocked_when_not_rate_limited():
+    assert should_block_rate_limited_resume(rate_limited=False, metadata_available=False) is False
+    assert should_block_rate_limited_resume(rate_limited=False, metadata_available=True) is False
+
+
+# ---------------------------------------------------------------------------
+# should_use_free_fallback — the activation gate
+# ---------------------------------------------------------------------------
+
+def test_gate_open_when_no_auth():
+    assert should_use_free_fallback(authenticated=False, rate_limited=False) is True
+
+
+def test_gate_open_when_rate_limited_even_if_authed():
+    assert should_use_free_fallback(authenticated=True, rate_limited=True) is True
+
+
+def test_gate_closed_when_authed_and_healthy():
+    # The critical guarantee: with working Spotify auth and no rate limit, the
+    # free source must NEVER activate.
+    assert should_use_free_fallback(authenticated=True, rate_limited=False) is False
+
+
+def test_gate_open_when_no_auth_and_rate_limited():
+    assert should_use_free_fallback(authenticated=False, rate_limited=True) is True
+
+
+# ---------------------------------------------------------------------------
+# should_offer_spotify_metadata — the availability gate the callers use
+# ---------------------------------------------------------------------------
+
+def test_offer_when_authed_even_if_no_free():
+    assert should_offer_spotify_metadata(authenticated=True, free_available=False) is True
+
+
+def test_offer_when_free_available_even_if_no_auth():
+    # The whole point: no auth but free available → Spotify source stays usable.
+    assert should_offer_spotify_metadata(authenticated=False, free_available=True) is True
+
+
+def test_not_offered_when_neither():
+    assert should_offer_spotify_metadata(authenticated=False, free_available=False) is False
+
+
+def test_full_composition_authed_healthy_never_uses_free():
+    # The critical no-regression guarantee end to end: authed + healthy →
+    # offered (official), and the per-request gate stays CLOSED.
+    assert should_offer_spotify_metadata(authenticated=True, free_available=True) is True
+    assert should_use_free_fallback(authenticated=True, rate_limited=False) is False
+
+
+def test_spotify_free_installed_returns_bool():
+    # Whatever the env, it's a cached bool and doesn't raise / hit network.
+    assert isinstance(spotify_free_installed(), bool)
+
+
+# ---------------------------------------------------------------------------
+# normalize_artist — raw web-player GraphQL → Spotify-compatible artist dict
+# ---------------------------------------------------------------------------
+
+# Trimmed from a real `SpotipyFree.artist()` response.
+_RAW_ARTIST = {
+    '__typename': 'Artist',
+    'id': '4Z8W4fKeB5YxbusRsdQVPb',
+    'uri': 'spotify:artist:4Z8W4fKeB5YxbusRsdQVPb',
+    'profile': {'name': 'Radiohead', 'biography': {'text': '...'}},
+    'stats': {'followers': 16239336, 'monthlyListeners': 45139421},
+    'visuals': {
+        'avatarImage': {
+            'sources': [
+                {'height': 640, 'width': 640, 'url': 'https://i.scdn.co/image/big'},
+                {'height': 160, 'width': 160, 'url': 'https://i.scdn.co/image/small'},
+            ]
+        }
+    },
+}
+
+# Trimmed from a real `artist_search` item's `data` (no usable image — only
+# color swatches under visualIdentity; SoulSync lazy-loads art separately).
+_RAW_SEARCH_ARTIST = {
+    '__typename': 'Artist',
+    'uri': 'spotify:artist:1dfeR4HaWDbWqFHLkxsg1d',
+    'profile': {'name': 'Queen'},
+    'visualIdentity': {'squareCoverImage': {'extractedColorSet': {}}},
+}
+
+
+def test_normalize_artist_full_shape():
+    out = normalize_artist(_RAW_ARTIST)
+    assert out['id'] == '4Z8W4fKeB5YxbusRsdQVPb'
+    assert out['name'] == 'Radiohead'
+    assert out['followers'] == {'total': 16239336}
+    assert out['images'][0]['url'] == 'https://i.scdn.co/image/big'
+    assert len(out['images']) == 2
+    assert out['external_urls'] == {
+        'spotify': 'https://open.spotify.com/artist/4Z8W4fKeB5YxbusRsdQVPb'
+    }
+    assert out['genres'] == []  # web player doesn't provide genres
+
+
+def test_normalize_artist_id_from_uri_when_no_id_field():
+    out = normalize_artist(_RAW_SEARCH_ARTIST)
+    assert out['id'] == '1dfeR4HaWDbWqFHLkxsg1d'
+    assert out['name'] == 'Queen'
+    assert out['images'] == []  # search items carry no usable image
+    assert out['external_urls']['spotify'].endswith('1dfeR4HaWDbWqFHLkxsg1d')
+
+
+def test_normalize_artist_handles_empty_and_none():
+    for bad in (None, {}, {'profile': None, 'stats': None, 'visuals': None}):
+        out = normalize_artist(bad)
+        assert out['name'] == ''
+        assert out['images'] == []
+        assert out['followers'] == {'total': 0}
+        assert out['external_urls'] == {}
+
+
+def test_normalize_artist_skips_imageless_sources():
+    raw = {'uri': 'spotify:artist:x', 'profile': {'name': 'A'},
+           'visuals': {'avatarImage': {'sources': [{'height': 1}, {'url': 'u'}]}}}
+    out = normalize_artist(raw)
+    assert out['images'] == [{'url': 'u', 'height': None, 'width': None}]
+
+
+# ---------------------------------------------------------------------------
+# SpotifyClient gate model — auto-bridge vs explicit opt-in vs no-surprise
+# (constructs the client via __new__ so no network/config init runs)
+# ---------------------------------------------------------------------------
+
+from unittest.mock import patch  # noqa: E402
+from core.spotify_client import SpotifyClient  # noqa: E402
+import core.spotify_free_metadata as _sfm  # noqa: E402
+
+
+def _gate(authed, has_creds, selected, installed, rate_limited):
+    c = SpotifyClient.__new__(SpotifyClient)
+    with patch.object(SpotifyClient, 'is_spotify_authenticated', return_value=authed), \
+         patch('core.spotify_client.config_manager') as cm, \
+         patch('core.spotify_client._is_globally_rate_limited', return_value=rate_limited), \
+         patch.object(_sfm, 'spotify_free_installed', return_value=installed):
+        cm.get_spotify_config.return_value = (
+            {'client_id': 'x', 'client_secret': 'y'} if has_creds else {})
+        cm.get.side_effect = lambda k, d=None: selected if k == 'metadata.spotify_free' else d
+        return c.is_spotify_metadata_available(), c._free_active()
+
+
+def test_connected_healthy_uses_official():
+    avail, free = _gate(authed=True, has_creds=True, selected=False, installed=True, rate_limited=False)
+    assert avail is True and free is False  # official; free never opens
+
+
+def test_plain_spotify_ratelimited_does_NOT_bridge():
+    # OPT-IN: a user on plain 'Spotify' (didn't pick Spotify Free) waits out a
+    # rate-limit ban — free does NOT auto-bridge for them. No surprise scraping.
+    avail, free = _gate(authed=False, has_creds=True, selected=False, installed=True, rate_limited=True)
+    assert avail is False and free is False
+
+
+def test_spotify_free_user_ratelimited_bridges():
+    # A user who DID pick Spotify Free and also connected an account: official
+    # when healthy, free bridges during a ban.
+    avail, free = _gate(authed=False, has_creds=True, selected=True, installed=True, rate_limited=True)
+    assert avail is True and free is True
+
+
+def test_spotify_free_user_healthy_uses_official():
+    avail, free = _gate(authed=True, has_creds=True, selected=True, installed=True, rate_limited=False)
+    assert avail is True and free is False   # picked Spotify Free but authed -> official
+
+
+def test_no_auth_picked_spotify_free_serves():
+    avail, free = _gate(authed=False, has_creds=False, selected=True, installed=True, rate_limited=False)
+    assert avail is True and free is True
+
+
+def test_no_auth_not_opted_in_does_nothing():
+    # The key no-surprise guarantee: a user who never chose Spotify gets no free.
+    avail, free = _gate(authed=False, has_creds=False, selected=False, installed=True, rate_limited=False)
+    assert avail is False and free is False
+
+
+def test_selected_but_package_missing_is_graceful():
+    avail, free = _gate(authed=False, has_creds=False, selected=True, installed=False, rate_limited=False)
+    assert avail is False and free is False
+
+
+def test_connected_ratelimited_but_no_package_no_bridge():
+    avail, free = _gate(authed=False, has_creds=True, selected=False, installed=False, rate_limited=True)
+    assert avail is False and free is False

tests/test_tag_writer_placeholder_guard.py

@@ -0,0 +1,143 @@
+"""#800 — Write Tags must never overwrite a real file value with a placeholder.
+
+A mis-grouped track sits under a 'Various Artists' / '[Unknown Album]' record,
+while the file itself is correctly tagged. Previously Write Tags stamped that
+junk over the good file (data loss). These pin the guard at both seams: the
+preview (build_tag_diff) and the actual write (write_tags_to_file).
+"""
+
+from __future__ import annotations
+
+import os
+import tempfile
+
+import pytest
+from mutagen.flac import FLAC
+
+from core.tag_writer import (
+    build_tag_diff,
+    guard_placeholder_overwrite,
+    is_placeholder_meta,
+    write_tags_to_file,
+)
+
+
+# ---------------------------------------------------------------------------
+# pure helpers
+# ---------------------------------------------------------------------------
+
+@pytest.mark.parametrize('val', [
+    None, '', '   ', 'Various Artists', 'various artists', 'VARIOUS ARTIST',
+    'Unknown Artist', 'Unknown Album', '[Unknown Album]', 'Unknown', 'Untitled Album',
+])
+def test_placeholder_values_detected(val):
+    assert is_placeholder_meta(val) is True
+
+
+@pytest.mark.parametrize('val', ['OneRepublic', 'Native (Deluxe)', 'Counting Stars', 'VA Movement'])
+def test_real_values_not_placeholder(val):
+    assert is_placeholder_meta(val) is False
+
+
+def test_guard_blocks_placeholder_over_real():
+    assert guard_placeholder_overwrite('Various Artists', 'OneRepublic') is None
+    assert guard_placeholder_overwrite('[Unknown Album]', 'Native (Deluxe)') is None
+
+
+def test_guard_allows_real_over_anything():
+    assert guard_placeholder_overwrite('OneRepublic', 'Old Wrong Name') == 'OneRepublic'
+    assert guard_placeholder_overwrite('OneRepublic', '') == 'OneRepublic'
+
+
+def test_guard_allows_placeholder_when_file_has_no_real_value():
+    # Legit compilation: file album-artist empty → 'Various Artists' still writes.
+    assert guard_placeholder_overwrite('Various Artists', '') == 'Various Artists'
+    assert guard_placeholder_overwrite('Various Artists', 'Various Artists') == 'Various Artists'
+
+
+# ---------------------------------------------------------------------------
+# build_tag_diff — the preview (screenshot #2 scenario)
+# ---------------------------------------------------------------------------
+
+def test_diff_protects_placeholder_over_real():
+    file_tags = {'title': 'Counting Stars', 'artist': 'OneRepublic',
+                 'album': 'Native (Deluxe)', 'album_artist': 'OneRepublic'}
+    db_data = {'title': 'Counting Stars', 'artist_name': 'Various Artists',
+               'album_title': '[Unknown Album]'}
+    diff = {d['field']: d for d in build_tag_diff(file_tags, db_data)}
+
+    assert diff['Title']['changed'] is False          # already equal
+    for f in ('Artist', 'Album', 'Album Artist'):
+        assert diff[f]['changed'] is False, f          # held back, not a wrong overwrite
+        assert diff[f]['protected'] is True, f
+    # Nothing real to write → no changes overall.
+    assert not any(d['changed'] for d in build_tag_diff(file_tags, db_data))
+
+
+def test_diff_real_db_value_still_changes():
+    file_tags = {'artist': 'Old Wrong'}
+    db_data = {'artist_name': 'OneRepublic'}
+    diff = {d['field']: d for d in build_tag_diff(file_tags, db_data)}
+    assert diff['Artist']['changed'] is True
+    assert diff['Artist']['protected'] is False
+
+
+def test_diff_compilation_va_writes_when_file_empty():
+    file_tags = {'album_artist': ''}  # no real value to protect
+    db_data = {'artist_name': 'Various Artists'}
+    diff = {d['field']: d for d in build_tag_diff(file_tags, db_data)}
+    assert diff['Album Artist']['changed'] is True
+    assert diff['Album Artist']['protected'] is False
+
+
+# ---------------------------------------------------------------------------
+# write_tags_to_file — end-to-end on a real FLAC
+# ---------------------------------------------------------------------------
+
+def _make_minimal_flac(path):
+    minimal = (
+        b'fLaC' + b'\x80\x00\x00\x22' + b'\x00\x10\x00\x10'
+        + b'\x00\x00\x00\x00\x00\x00' + b'\x0a\xc4\x42\xf0\x00\x00\x00\x00' + b'\x00' * 16
+    )
+    with open(path, 'wb') as f:
+        f.write(minimal)
+
+
+@pytest.fixture
+def flac_path():
+    fd, path = tempfile.mkstemp(suffix='.flac')
+    os.close(fd)
+    _make_minimal_flac(path)
+    yield path
+    try:
+        os.remove(path)
+    except OSError:
+        pass
+
+
+def test_write_preserves_real_value_against_placeholder(flac_path):
+    # 1) lay down correct tags (the file is correctly tagged)
+    write_tags_to_file(flac_path, {
+        'title': 'Counting Stars', 'artist_name': 'OneRepublic',
+        'album_title': 'Native (Deluxe)',
+    }, embed_cover=False)
+
+    # 2) attempt to write the mis-grouped DB junk over it
+    result = write_tags_to_file(flac_path, {
+        'title': 'Counting Stars', 'artist_name': 'Various Artists',
+        'album_title': '[Unknown Album]',
+    }, embed_cover=False)
+    assert result['success'] is True
+
+    audio = FLAC(flac_path)
+    assert audio.get('artist') == ['OneRepublic']          # preserved, not clobbered
+    assert audio.get('album') == ['Native (Deluxe)']       # preserved
+    assert audio.get('albumartist') == ['OneRepublic']     # preserved
+
+
+def test_write_real_value_still_overwrites(flac_path):
+    write_tags_to_file(flac_path, {'artist_name': 'OneRepublic'}, embed_cover=False)
+    # A real (non-placeholder) new value must still overwrite normally.
+    result = write_tags_to_file(flac_path, {'artist_name': 'Coldplay'}, embed_cover=False)
+    assert result['success'] is True
+    assert FLAC(flac_path).get('artist') == ['Coldplay']

tests/test_torrent_client_adapters.py

@@ -263,6 +263,58 @@ def test_transmission_normalises_bare_host_to_rpc_path() -> None:
     assert adapter._url == 'http://host:9091/transmission/rpc'
 
 
+# ---------------------------------------------------------------------------
+# URL scheme normalization (#790)
+# ---------------------------------------------------------------------------
+
+
+def test_normalize_client_url_prepends_http_when_scheme_missing() -> None:
+    from core.torrent_clients.base import normalize_client_url
+    # The exact shapes users type: bare IP:port, bare DNS name:port, bare host.
+    assert normalize_client_url('192.168.1.5:8080') == 'http://192.168.1.5:8080'
+    assert normalize_client_url('qbittorrent.lan:8080') == 'http://qbittorrent.lan:8080'
+    assert normalize_client_url('myhost') == 'http://myhost'
+
+
+def test_normalize_client_url_preserves_existing_scheme_and_trims() -> None:
+    from core.torrent_clients.base import normalize_client_url
+    assert normalize_client_url('http://host:8080') == 'http://host:8080'
+    assert normalize_client_url('https://host') == 'https://host'
+    assert normalize_client_url('  http://host:8080/  ') == 'http://host:8080'
+    assert normalize_client_url('') == ''
+    assert normalize_client_url(None) == ''
+
+
+def test_qbit_load_config_defaults_scheme_for_bare_host() -> None:
+    """Regression #790: a bare ``host:port`` config (no scheme) must become an
+    http:// URL. Otherwise requests can't pick an adapter and raises
+    'No connection adapters were found for ...', which surfaced to the user as
+    a generic 'qbittorrent probe failed'."""
+    adapter = QBittorrentAdapter.__new__(QBittorrentAdapter)
+    import threading
+    adapter._session = None
+    adapter._session_lock = threading.Lock()
+    with patch('core.torrent_clients.qbittorrent.config_manager') as cm:
+        cm.get.side_effect = lambda key, default='': {
+            'torrent_client.url': '192.168.1.5:8080',
+        }.get(key, default)
+        adapter._load_config()
+    assert adapter._url == 'http://192.168.1.5:8080'
+
+
+def test_deluge_load_config_defaults_scheme_for_bare_host() -> None:
+    adapter = DelugeAdapter.__new__(DelugeAdapter)
+    import threading
+    adapter._session = None
+    adapter._session_lock = threading.Lock()
+    with patch('core.torrent_clients.deluge.config_manager') as cm:
+        cm.get.side_effect = lambda key, default='': {
+            'torrent_client.url': 'deluge.lan:8112',
+        }.get(key, default)
+        adapter._load_config()
+    assert adapter._url == 'http://deluge.lan:8112'
+
+
 def test_transmission_session_id_renegotiation() -> None:
     """Transmission rejects the first call with 409 and a fresh
     ``X-Transmission-Session-Id`` header; the adapter must store it

tests/test_worker_artist_match_gate.py

@@ -0,0 +1,114 @@
+"""Tests for the shared artist-match gate in core/worker_utils.py.
+
+Two jobs:
+  * artist_name_matches — a stricter (0.85) gate than the 0.80 used for
+    album/track titles, so short-name false positives ('ODESZA'/'odessa',
+    'Blance'/'Blanke', 'Lady A'/'Lady Gaga') are rejected.
+  * source_id_conflict / accept_artist_match — refuse to store a source id that
+    a DIFFERENTLY-named artist already holds, while still allowing a same-named
+    artist (the same act indexed on two media servers) to share it.
+"""
+
+from __future__ import annotations
+
+import pytest
+
+from core import worker_utils as wu
+from database.music_database import MusicDatabase
+
+
+@pytest.fixture
+def db(tmp_path):
+    return MusicDatabase(str(tmp_path / "music.db"))
+
+
+def _insert(db, *, artist_id, name, **extra):
+    cols = ["id", "name", "server_source"] + list(extra.keys())
+    vals = [artist_id, name, "plex"] + list(extra.values())
+    ph = ",".join("?" for _ in cols)
+    with db._get_connection() as conn:
+        conn.execute(f"INSERT INTO artists ({','.join(cols)}) VALUES ({ph})", vals)
+        conn.commit()
+
+
+# ---------------------------------------------------------------------------
+# artist_name_matches — the 0.85 gate
+# ---------------------------------------------------------------------------
+
+@pytest.mark.parametrize("a,b", [
+    ("ODESZA", "odessa"),
+    ("Blance", "Blanke"),
+    ("COLLEGE", "Colle"),
+    ("Lady A", "Lady Gaga"),
+    ("M&O", "M.O.P."),
+])
+def test_near_name_pairs_rejected_at_085(a, b):
+    assert wu.artist_name_matches(a, b) is False
+
+
+@pytest.mark.parametrize("a,b", [
+    ("Saib", "saib."),            # punctuation only → identical
+    ("-Us.", "Us"),
+    ("Kendrick Lamar", "KENDRICK LAMAR"),
+    ("Beyoncé", "Beyonce"),
+])
+def test_true_variants_still_match(a, b):
+    assert wu.artist_name_matches(a, b) is True
+
+
+# ---------------------------------------------------------------------------
+# source_id_conflict — different name blocks, same name allowed
+# ---------------------------------------------------------------------------
+
+def test_conflict_when_different_named_artist_holds_id(db):
+    _insert(db, artist_id="1", name="Kendrick Lamar", deezer_id="525046")
+    # Trying to give Jorja the same id → conflict reports the holder.
+    assert wu.source_id_conflict(db, "deezer_id", "525046", "2", "Jorja Smith") == "Kendrick Lamar"
+
+
+def test_no_conflict_for_same_named_artist_two_servers(db):
+    # Radiohead already on plex with this id; the jellyfin Radiohead (id 2) may
+    # legitimately share it.
+    _insert(db, artist_id="1", name="Radiohead", deezer_id="999")
+    assert wu.source_id_conflict(db, "deezer_id", "999", "2", "Radiohead") is None
+
+
+def test_no_conflict_when_same_row_holds_it(db):
+    _insert(db, artist_id="1", name="Radiohead", deezer_id="999")
+    # Re-matching the same artist to its own id is fine.
+    assert wu.source_id_conflict(db, "deezer_id", "999", "1", "Radiohead") is None
+
+
+def test_no_conflict_when_id_unused(db):
+    assert wu.source_id_conflict(db, "deezer_id", "12345", "1", "Anyone") is None
+
+
+def test_unknown_column_is_refused(db):
+    assert wu.source_id_conflict(db, "evil_id", "x", "1", "Anyone") is None
+
+
+# ---------------------------------------------------------------------------
+# accept_artist_match — combined gate
+# ---------------------------------------------------------------------------
+
+def test_accept_rejects_name_mismatch(db):
+    ok, reason = wu.accept_artist_match(db, "deezer_id", "1", "1", "ODESZA", "odessa")
+    assert ok is False
+    assert "name mismatch" in reason
+
+
+def test_accept_rejects_id_already_claimed_by_other(db):
+    _insert(db, artist_id="1", name="Kendrick Lamar", deezer_id="525046")
+    ok, reason = wu.accept_artist_match(
+        db, "deezer_id", "525046", "2", "Jorja Smith", "Jorja Smith"
+    )
+    assert ok is False
+    assert "already claimed" in reason
+
+
+def test_accept_passes_clean_match(db):
+    ok, reason = wu.accept_artist_match(
+        db, "deezer_id", "111", "1", "Kendrick Lamar", "Kendrick Lamar"
+    )
+    assert ok is True
+    assert reason == ""

web_server.py

@@ -40,7 +40,7 @@ logger = setup_logging(_log_level, _log_path)
 
 # App version — single source of truth for backup metadata, system-info, update check, etc.
 # Semver: MAJOR.MINOR.PATCH. Bump at each dev→main release.
-_SOULSYNC_BASE_VERSION = "2.6.6"
+_SOULSYNC_BASE_VERSION = "2.6.7"
 
 def _build_version_string():
     """Append short commit hash to version when available (e.g. 2.35+abc1234)."""
@@ -862,19 +862,6 @@ duplicate_cleaner_state = {
 duplicate_cleaner_lock = threading.Lock()
 duplicate_cleaner_executor = ThreadPoolExecutor(max_workers=1, thread_name_prefix="DuplicateCleaner")
 
-# Retag Tool Globals
-retag_state = {
-    "status": "idle",
-    "phase": "Ready",
-    "progress": 0,
-    "current_track": "",
-    "total_tracks": 0,
-    "processed": 0,
-    "error_message": "",
-}
-retag_lock = threading.Lock()
-retag_executor = ThreadPoolExecutor(max_workers=1, thread_name_prefix="RetagWorker")
-
 # Download Missing Tracks Modal State Management
 # Thread-safe state tracking for modal download functionality.
 # Shared task/batch state now lives in core.runtime_state.
@@ -1709,7 +1696,6 @@ def _shutdown_runtime_components():
         (db_update_executor, "db update executor"),
         (quality_scanner_executor, "quality scanner executor"),
         (duplicate_cleaner_executor, "duplicate cleaner executor"),
-        (retag_executor, "retag executor"),
         (sync_executor, "sync executor"),
         (missing_download_executor, "missing download executor"),
         (album_bundle_executor, "album bundle executor"),
@@ -2334,7 +2320,7 @@ def get_status():
 
         status_data = {
             'metadata_source': metadata_status['metadata_source'],
-            'spotify': metadata_status['spotify'],
+            'spotify': _spotify_status_with_availability(metadata_status['spotify']),
             'media_server': _status_cache['media_server'],
             'soulseek': soulseek_data,
             'active_media_server': active_server,
@@ -3679,10 +3665,23 @@ def settings_config_status_endpoint():
     Drives the green/yellow header gradient. No API calls — just config reads.
     """
     try:
-        return jsonify({
+        result = {
             service: {'configured': _is_service_configured(service)}
             for service in SERVICE_CONFIG_REGISTRY
-        })
+        }
+        # Spotify Free: Spotify metadata can be available without credentials
+        # (opt-in no-creds source). Surface that separately so the search source
+        # picker offers Spotify, while `configured` (the Connections indicator)
+        # keeps meaning "has client credentials".
+        if 'spotify' in result:
+            try:
+                meta_avail = bool(spotify_client and spotify_client.is_spotify_metadata_available())
+            except Exception:
+                meta_avail = False
+            result['spotify']['metadata_available'] = (
+                result['spotify']['configured'] or meta_avail
+            )
+        return jsonify(result)
     except Exception as e:
         logger.error(f"config-status error: {e}")
         return jsonify({"error": str(e)}), 500
@@ -5621,6 +5620,7 @@ def start_sync():
 
 # Search route bodies live in core/search/* — these routes are thin handlers.
 from core.search import basic as _search_basic
+from core.search import by_id as _search_by_id
 from core.search import library_check as _search_library_check
 from core.search import orchestrator as _search_orchestrator
 from core.search import stream as _search_stream
@@ -5739,6 +5739,34 @@ def enhanced_search():
         return jsonify({"error": str(e)}), 500
 
 
+@app.route('/api/enhanced-search/by-id', methods=['POST'])
+def enhanced_search_by_id():
+    """Resolve a pasted metadata link to a single album or track (#775).
+
+    A provider URL (Spotify/Apple/MusicBrainz/Deezer) is looked up directly
+    on the owning source via its get-by-id — no fuzzy search, no scoring. The
+    domain pins the source and the path pins album-vs-track, so it's
+    unambiguous. Returns the same dropdown shape the normal enhanced search
+    renders, plus the resolving ``source`` so the frontend can route
+    downloads/imports through the existing flow.
+
+    Body: ``{"query": "<provider link or spotify: URI>"}``. Links only — a
+    bare ID is rejected with a hint, since it carries no source or type.
+    """
+    data = request.get_json() or {}
+    raw = (data.get('query') or '').strip()
+    if not raw:
+        return jsonify(_search_by_id._empty_result(''))
+
+    try:
+        deps = _build_search_deps()
+        result = _search_by_id.resolve_identifier(raw, deps)
+        return jsonify(result)
+    except Exception as e:
+        logger.error(f"Link/ID resolve error: {e}")
+        return jsonify({"error": str(e)}), 500
+
+
 @app.route('/api/enhanced-search/source/<source_name>', methods=['POST'])
 def enhanced_search_source(source_name):
     """Streaming NDJSON search for one alternate metadata source.
@@ -7638,6 +7666,26 @@ def _find_library_artist_for_source(database, source, source_artist_id, artist_n
     )
 
 
+def _resolve_source_artist_name(source, artist_id):
+    """Resolve a source artist's display name by id, or '' on any failure.
+
+    Reuses the #775 link-resolver's per-source artist fetch so we have one
+    place that knows each source's get-by-id quirks. Used by the artist-detail
+    library upgrade to disambiguate a duplicated/corrupt source id by name
+    when the URL-driven navigation didn't carry a name.
+    """
+    try:
+        deps = _build_search_deps()
+        client, _available = _search_orchestrator.resolve_client(source, deps)
+        if client is None:
+            return ''
+        data = _search_by_id._fetch_artist(client, source, artist_id)
+        return (data or {}).get('name') or ''
+    except Exception as e:
+        logger.debug(f"Source artist name resolution failed for {source}:{artist_id}: {e}")
+        return ''
+
+
 def _build_source_only_artist_detail(artist_id, artist_name, source):
     """Thin wrapper around ``core.artist_source_detail.build_source_only_artist_detail``.
 
@@ -7739,6 +7787,18 @@ def get_artist_detail(artist_id):
             library_pk = _find_library_artist_for_source(
                 database, source_param, artist_id, artist_name_arg
             )
+            # URL-driven navigation carries no name, so a duplicated/corrupt
+            # source id (one Deezer id on several artists) can't be matched by
+            # the id alone — it's ambiguous and the lookup bails. Resolve the
+            # artist's name from the source and retry so an owned artist still
+            # gets the rich library view instead of the bare source one.
+            if not library_pk and not artist_name_arg:
+                resolved_name = _resolve_source_artist_name(source_param, artist_id)
+                if resolved_name:
+                    artist_name_arg = resolved_name
+                    library_pk = _find_library_artist_for_source(
+                        database, source_param, artist_id, artist_name_arg
+                    )
             if library_pk:
                 logger.info(
                     f"Source-id {source_param}:{artist_id} matched library artist "
@@ -9336,6 +9396,13 @@ def _build_library_tag_db_data(track_data, album_genres=None):
         if artists_list:
             db_data['artists_list'] = artists_list
 
+    # Carry the known source IDs through so they get embedded too (the writer
+    # only acts on the ones present). These come from t.* on the track row.
+    for _k in ('spotify_track_id', 'itunes_track_id', 'musicbrainz_recording_id'):
+        _v = track_data.get(_k)
+        if _v:
+            db_data[_k] = _v
+
     return db_data
 
 
@@ -9761,6 +9828,159 @@ def get_write_tags_batch_status():
         return jsonify(state)
 
 
+# ── Reconcile embedded provider IDs (gap-fill DB from file tags) ──
+#
+# Files that SoulSync (or MusicBrainz Picard) already tagged carry Spotify /
+# iTunes / MusicBrainz / Deezer / Tidal / AudioDB / Genius IDs in their
+# metadata. Reading them back and gap-filling the {provider}_id +
+# {provider}_match_status='matched' columns lets the enrichment workers skip
+# the API lookup entirely — large API savings on an already-tagged library.
+# Gap-fill only: an existing id is never overwritten (see
+# core/library/embedded_id_reconcile.py).
+def _reconcile_library_tracks(conn, track_ids=None, on_progress=None, should_stop=None):
+    """Run the embedded-ID reconcile with web-server path resolution injected.
+
+    Thin wrapper over core.library.embedded_id_reconcile.reconcile_library that
+    supplies the read_tags callable (docker/library path resolution + mutagen
+    read). Used by the manual backfill job and available for any scoped
+    reconcile. ``track_ids=None`` => whole library.
+    """
+    from core.library.file_tags import read_embedded_tags
+    from core.library.embedded_id_reconcile import reconcile_library
+
+    def _read_tags(file_path):
+        resolved = _resolve_library_file_path(file_path)
+        if not resolved:
+            return None
+        info = read_embedded_tags(resolved)
+        return info.get('tags') if info.get('available') else None
+
+    return reconcile_library(conn, _read_tags, track_ids=track_ids,
+                             on_progress=on_progress, should_stop=should_stop)
+
+
+def _reconcile_after_scan(worker):
+    """Gap-fill embedded provider IDs for tracks a scan newly inserted.
+
+    Runs after a library scan/deep-scan completes, scoped to the rows the
+    worker actually INSERTED this run (``worker._new_track_ids``). New files
+    are written with empty provider-id columns, so this reads their tags and
+    fills any IDs present — keeping the DB current without a manual backfill.
+    Best-effort: never raises into the scan flow.
+    """
+    try:
+        new_ids = list(getattr(worker, '_new_track_ids', None) or [])
+        if not new_ids:
+            return
+        n = len(new_ids)
+        try:
+            _db_update_phase_callback(
+                f"Reading file tags for {n} new track{'s' if n != 1 else ''}…")
+        except Exception:  # noqa: S110 — best-effort UI phase, never block the reconcile
+            pass
+
+        def _on_progress(totals, title):
+            try:
+                pct = (totals.processed / totals.total * 100) if totals.total else 100
+                _db_update_progress_callback(title, totals.processed, totals.total, pct)
+            except Exception:  # noqa: S110 — best-effort UI progress tick
+                pass
+
+        database = get_database()
+        conn = database._get_connection()
+        try:
+            totals = _reconcile_library_tracks(conn, track_ids=new_ids, on_progress=_on_progress)
+            logger.info(
+                "[Reconcile] Post-scan: filled %d id(s) across %d row(s) from %d new "
+                "track(s) (%d unreadable, %d conflicts)",
+                totals.ids_filled, totals.entities_updated, totals.processed,
+                totals.unreadable, totals.conflicts,
+            )
+        finally:
+            conn.close()
+    except Exception as e:
+        logger.warning("[Reconcile] Post-scan reconcile failed (non-fatal): %s", e)
+
+
+_reconcile_ids_state = {
+    'status': 'idle',          # idle | running | done
+    'total': 0,
+    'processed': 0,
+    'entities_updated': 0,     # track/album/artist rows written
+    'ids_filled': 0,           # individual id columns filled
+    'conflicts': 0,            # embedded id disagreed with a stored id (not applied)
+    'unreadable': 0,           # files missing / unreadable by mutagen
+    'current': '',
+}
+_reconcile_ids_lock = threading.Lock()
+
+
+@app.route('/api/library/reconcile-embedded-ids', methods=['POST'])
+def reconcile_embedded_ids():
+    """Scan every library file for embedded provider IDs and gap-fill them
+    into the DB so enrichment workers skip the API lookup. Runs in the
+    background; poll the status endpoint for progress."""
+    try:
+        with _reconcile_ids_lock:
+            if _reconcile_ids_state['status'] == 'running':
+                return jsonify({"success": False, "error": "A reconcile is already in progress"}), 409
+            _reconcile_ids_state.update({
+                'status': 'running', 'total': 0, 'processed': 0,
+                'entities_updated': 0, 'ids_filled': 0, 'conflicts': 0,
+                'unreadable': 0, 'current': 'Starting…',
+            })
+
+        database = get_database()
+
+        def _run():
+            conn = None
+            try:
+                conn = database._get_connection()
+
+                def _on_progress(totals, title):
+                    with _reconcile_ids_lock:
+                        _reconcile_ids_state.update({
+                            'total': totals.total,
+                            'processed': totals.processed,
+                            'entities_updated': totals.entities_updated,
+                            'ids_filled': totals.ids_filled,
+                            'conflicts': totals.conflicts,
+                            'unreadable': totals.unreadable,
+                            'current': title,
+                        })
+
+                # Whole-library backfill (track_ids=None). Shares the exact
+                # orchestration used by the on-scan auto-reconcile hook.
+                _reconcile_library_tracks(conn, on_progress=_on_progress)
+            except Exception as e:
+                logger.error(f"Reconcile embedded IDs background error: {e}")
+            finally:
+                if conn is not None:
+                    try:
+                        conn.close()
+                    except Exception:  # noqa: S110 — connection cleanup, nothing to recover
+                        pass
+                with _reconcile_ids_lock:
+                    _reconcile_ids_state['status'] = 'done'
+                    _reconcile_ids_state['current'] = ''
+
+        thread = threading.Thread(target=_run, daemon=True, name="ReconcileEmbeddedIds")
+        thread.start()
+        return jsonify({"success": True, "message": "Reconcile started"})
+
+    except Exception as e:
+        logger.error(f"Reconcile embedded IDs kickoff error: {e}")
+        with _reconcile_ids_lock:
+            _reconcile_ids_state['status'] = 'idle'
+        return jsonify({"success": False, "error": str(e)}), 500
+
+
+@app.route('/api/library/reconcile-embedded-ids/status', methods=['GET'])
+def get_reconcile_embedded_ids_status():
+    """Poll the status of the embedded-ID reconcile job."""
+    with _reconcile_ids_lock:
+        return jsonify(dict(_reconcile_ids_state))
+
 
 # ── ReplayGain Analysis endpoints ──
 
@@ -11096,6 +11316,18 @@ def library_manual_match():
             if cursor.rowcount == 0:
                 return jsonify({"success": False, "error": "Entity not found"}), 404
 
+        # #758 — a manual ALBUM match also pins (and LOCKS) the canonical album
+        # version to the chosen release, so the auto resolve job and every tool
+        # that reads the canonical pin (track-number repair, reorganize,
+        # missing-tracks) honor the user's edition instead of re-resolving back
+        # to the deluxe. The lock survives future enrichment/resolution cycles.
+        try:
+            from core.metadata.canonical_version import should_pin_manual_canonical
+            if should_pin_manual_canonical(entity_type, service):
+                database.set_album_canonical(entity_id, service, service_id, 1.0, locked=True)
+        except Exception as e:
+            logger.warning("Manual canonical pin failed for album %s: %s", entity_id, e)
+
         # Re-fetch fresh data
         artist_id = data.get('artist_id', entity_id)
         if entity_type != 'artist':
@@ -14267,45 +14499,6 @@ _download_retry_attempts = {}  # {context_key: {'count': N, 'first_attempt': tim
 _download_retry_max = 10  # Max retries before giving up (10 seconds with 1s poll interval)
 _download_retry_lock = threading.Lock()
 
-# Retag worker logic lives in core/library/retag.py.
-from core.library import retag as _library_retag
-
-
-def _build_retag_deps():
-    """Build the RetagDeps bundle from web_server.py globals on each call."""
-    from database.music_database import get_database as _get_db
-
-    def _get_state():
-        return retag_state
-
-    def _set_state(value):
-        global retag_state
-        retag_state = value
-
-    from core.metadata.lyrics import generate_lrc_file as _generate_lrc_file
-
-    return _library_retag.RetagDeps(
-        config_manager=config_manager,
-        retag_lock=retag_lock,
-        spotify_client=spotify_client,
-        get_audio_quality_string=_get_audio_quality_string,
-        enhance_file_metadata=_enhance_file_metadata,
-        build_final_path_for_track=_build_final_path_for_track,
-        safe_move_file=_safe_move_file,
-        cleanup_empty_directories=_cleanup_empty_directories,
-        download_cover_art=_download_cover_art,
-        docker_resolve_path=docker_resolve_path,
-        _get_retag_state=_get_state,
-        _set_retag_state=_set_state,
-        get_database=_get_db,
-        generate_lrc_file=_generate_lrc_file,
-    )
-
-
-def _execute_retag(group_id, album_id):
-    return _library_retag.execute_retag(group_id, album_id, _build_retag_deps())
-
-
 def _automatic_wishlist_cleanup_after_db_update():
     """Automatic wishlist cleanup that runs after database updates."""
     return _cleanup_wishlist_after_db_update(logger=logger)
@@ -15035,6 +15228,11 @@ def _run_db_update_task(full_refresh, server_type):
             db_update_worker.connect_callback('finished', _db_update_finished_callback)
             db_update_worker.connect_callback('error', _db_update_error_callback)
 
+    # Auto-reconcile runs as the FINAL scan phase (inside run(), before the
+    # 'finished' signal) so status stays 'running' through it — automations,
+    # the dashboard card, and the Tools page all treat it as part of the scan.
+    db_update_worker.post_scan_hook = _reconcile_after_scan
+
     # This is a blocking call that runs the worker logic
     db_update_worker.run()
 
@@ -15083,6 +15281,9 @@ def _run_deep_scan_task(server_type):
             db_update_worker.connect_callback('finished', _db_update_finished_callback)
             db_update_worker.connect_callback('error', _db_update_error_callback)
 
+    # Auto-reconcile runs as the final scan phase (see _run_database_update_task).
+    db_update_worker.post_scan_hook = _reconcile_after_scan
+
     # Run deep scan instead of normal run()
     db_update_worker.run_deep_scan()
 
@@ -16454,115 +16655,6 @@ def stop_duplicate_cleaner():
 # == RETAG TOOL ENDPOINTS      ==
 # ===============================
 
-@app.route('/api/retag/stats', methods=['GET'])
-def get_retag_stats():
-    """Get retag tool statistics for the dashboard card."""
-    from database.music_database import get_database
-    db = get_database()
-    stats = db.get_retag_stats()
-    return jsonify({"success": True, **stats})
-
-@app.route('/api/retag/groups', methods=['GET'])
-def get_retag_groups():
-    """Get all retag groups sorted by artist name."""
-    from database.music_database import get_database
-    db = get_database()
-    groups = db.get_retag_groups()
-    return jsonify({"success": True, "groups": groups})
-
-@app.route('/api/retag/groups/<int:group_id>/tracks', methods=['GET'])
-def get_retag_group_tracks(group_id):
-    """Get tracks for a specific retag group."""
-    from database.music_database import get_database
-    db = get_database()
-    tracks = db.get_retag_tracks(group_id)
-    return jsonify({"success": True, "tracks": tracks})
-
-@app.route('/api/retag/search', methods=['GET'])
-def search_retag_albums():
-    """Search for albums to use for retagging (uses Spotify/iTunes fallback)."""
-    query = request.args.get('q', '').strip()
-    if not query:
-        return jsonify({"success": False, "error": "Query parameter 'q' is required"}), 400
-
-    limit = min(int(request.args.get('limit', 12)), 50)
-    try:
-        results = spotify_client.search_albums(query, limit=limit)
-        albums = []
-        for a in results:
-            albums.append({
-                'id': str(a.id),
-                'name': a.name,
-                'artist': ', '.join(a.artists) if a.artists else 'Unknown Artist',
-                'release_date': a.release_date or '',
-                'total_tracks': a.total_tracks,
-                'image_url': a.image_url,
-                'album_type': a.album_type or 'album'
-            })
-        return jsonify({"success": True, "albums": albums})
-    except Exception as e:
-        logger.error(f"[Retag] Album search error: {e}")
-        return jsonify({"success": False, "error": str(e)}), 500
-
-@app.route('/api/retag/execute', methods=['POST'])
-def execute_retag():
-    """Start a retag operation for a group with a new album match."""
-    data = request.get_json()
-    if not data:
-        return jsonify({"success": False, "error": "JSON body required"}), 400
-
-    group_id = data.get('group_id')
-    album_id = data.get('album_id')
-    if not group_id or not album_id:
-        return jsonify({"success": False, "error": "group_id and album_id are required"}), 400
-
-    with retag_lock:
-        if retag_state["status"] == "running":
-            return jsonify({"success": False, "error": "A retag operation is already running"}), 409
-
-    retag_executor.submit(_execute_retag, group_id, str(album_id))
-    return jsonify({"success": True, "message": "Retag operation started"})
-
-@app.route('/api/retag/status', methods=['GET'])
-def get_retag_status():
-    """Get the current retag operation status."""
-    with retag_lock:
-        return jsonify(dict(retag_state))
-
-@app.route('/api/retag/groups/<int:group_id>', methods=['DELETE'])
-def delete_retag_group(group_id):
-    """Delete a retag group (files are NOT deleted)."""
-    from database.music_database import get_database
-    db = get_database()
-    success = db.delete_retag_group(group_id)
-    if success:
-        return jsonify({"success": True})
-    else:
-        return jsonify({"success": False, "error": "Group not found"}), 404
-
-@app.route('/api/retag/groups/delete-batch', methods=['POST'])
-def delete_retag_groups_batch():
-    """Delete multiple retag groups at once."""
-    from database.music_database import get_database
-    data = request.get_json() or {}
-    group_ids = data.get('group_ids', [])
-    if not group_ids:
-        return jsonify({"success": False, "error": "No group IDs provided"}), 400
-    db = get_database()
-    removed = 0
-    for gid in group_ids:
-        if db.delete_retag_group(int(gid)):
-            removed += 1
-    return jsonify({"success": True, "removed": removed})
-
-@app.route('/api/retag/groups/clear-all', methods=['POST'])
-def clear_all_retag_groups():
-    """Delete all retag groups."""
-    from database.music_database import get_database
-    db = get_database()
-    count = db.delete_all_retag_groups()
-    return jsonify({"success": True, "removed": count})
-
 # ===============================
 # == DOWNLOAD MISSING TRACKS   ==
 # ===============================
@@ -18227,13 +18319,26 @@ def get_server_playlist_tracks(playlist_id):
         # exact/fuzzy passes entirely. Stale-cache safe — if the cached
         # server track no longer exists, the override is silently
         # skipped and normal matching runs.
-        from core.sync.match_overrides import resolve_match_overrides
+        from core.sync.match_overrides import resolve_durable_match_server_id, resolve_match_overrides
         _db_for_overrides = get_database()
-        _override_pairs = resolve_match_overrides(
-            source_tracks,
-            server_tracks,
-            lambda src_id: ((_db_for_overrides.read_sync_match_cache(src_id, active_server) or {}).get('server_track_id')),
-        )
+        # Set of server track ids currently in this playlist — used to validate
+        # a re-resolved durable match actually exists before pairing it.
+        _server_ids = {str(t.get('id')) for t in server_tracks if isinstance(t, dict) and t.get('id') is not None}
+        _ov_profile = get_current_profile_id()
+
+        def _override_lookup(src_id):
+            # 1) Fast override cache (cleared on every rescan).
+            cached = _db_for_overrides.read_sync_match_cache(src_id, active_server) or {}
+            if cached.get('server_track_id'):
+                return cached['server_track_id']
+            # 2) Durable manual library match — survives a rescan (#787), so a
+            #    Find & Add / manual match keeps pairing after a DB scan. Re-
+            #    resolves a stale id via the stored file path when needed.
+            return resolve_durable_match_server_id(
+                _db_for_overrides, _ov_profile, src_id, active_server, _server_ids
+            )
+
+        _override_pairs = resolve_match_overrides(source_tracks, server_tracks, _override_lookup)
 
         combined = reconcile_playlist(source_tracks, server_tracks, _override_pairs)
 
@@ -18349,27 +18454,55 @@ def server_playlist_replace_track(playlist_id):
         return jsonify({"success": False, "error": str(e)}), 500
 
 
-def _persist_find_and_add_match(source_track_id, server_source, server_track_id, server_track_title, source_title, source_artist):
-    """Wrap match-override persistence with the active DB. No-op when
-    source_track_id is missing (e.g. add to a non-mirrored playlist)."""
+def _persist_find_and_add_match(source_track_id, server_source, server_track_id, server_track_title, source_title, source_artist, source='spotify'):
+    """Persist a Find & Add selection two ways. No-op when source_track_id is
+    missing (e.g. add to a non-mirrored playlist).
+
+    1. ``sync_match_cache`` override — fast auto-match on the next sync, but
+       wiped on every library rescan.
+    2. A DURABLE manual library match (#787) — survives a rescan, so the
+       source→library pairing sticks in the sync display AND the download loop
+       stops re-fetching it. This is the unification the issue asked for:
+       Find & Add now also records a manual library match (one-way; the manual
+       match tool has no playlist to act on, so it doesn't reverse-create)."""
     if not source_track_id:
         return
+    db = get_database()
     try:
         from core.sync.match_overrides import record_manual_match
         ok = record_manual_match(
-            get_database(),
+            db,
             source_track_id=source_track_id,
             server_source=server_source,
             server_track_id=server_track_id,
-            server_track_title=server_track_title,
             source_title=source_title,
             source_artist=source_artist,
+            server_track_title=server_track_title,
         )
         if ok:
             logger.info(f"[ServerPlaylist] Persisted Find & Add override: {source_track_id} → {server_track_id} ({server_source})")
     except Exception as e:
         logger.warning(f"[ServerPlaylist] Failed to persist Find & Add override: {e}")
 
+    # Durable manual library match — survives a rescan (the override above does not).
+    try:
+        from core.library import manual_library_match as _mlm
+        file_path = ''
+        try:
+            _rows = db.api_get_tracks_by_ids([server_track_id])
+            if _rows:
+                file_path = _rows[0].get('file_path', '') or ''
+        except Exception as _fp_err:
+            logger.debug(f"[ServerPlaylist] file_path lookup for manual match failed: {_fp_err}")
+        _mlm.save_match(
+            db, get_current_profile_id(), (source or 'spotify'), str(source_track_id), str(server_track_id),
+            source_title=source_title, source_artist=source_artist,
+            server_source=server_source, library_file_path=file_path,
+        )
+        logger.info(f"[ServerPlaylist] Recorded durable manual library match: {source_track_id} → {server_track_id}")
+    except Exception as e:
+        logger.warning(f"[ServerPlaylist] Failed to record durable manual match: {e}")
+
 
 @app.route('/api/server/playlist/<playlist_id>/add-track', methods=['POST'])
 def server_playlist_add_track(playlist_id):
@@ -18391,6 +18524,9 @@ def server_playlist_add_track(playlist_id):
         source_title = data.get('source_title') or ''
         source_artist = data.get('source_artist') or ''
         server_track_title = data.get('server_track_title') or ''
+        # Provider of the source track (spotify/deezer/...) for the durable
+        # manual match. Retrieval is source-agnostic, so this is metadata.
+        source_provider = data.get('source') or 'spotify'
 
         if not track_id:
             return jsonify({"success": False, "error": "track_id required"}), 400
@@ -18431,7 +18567,7 @@ def server_playlist_add_track(playlist_id):
                 except Exception:
                     _existing = set()
                 if str(track_id) in _existing:
-                    _persist_find_and_add_match(source_track_id, active_server, track_id, server_track_title or new_item.title, source_title, source_artist)
+                    _persist_find_and_add_match(source_track_id, active_server, track_id, server_track_title or new_item.title, source_title, source_artist, source_provider)
                     return jsonify({"success": True, "message": "Track linked"})
 
             logger.info(f"[ServerPlaylist] Adding track: '{new_item.title}' (ratingKey={new_item.ratingKey}) to playlist '{playlist_name}'")
@@ -18455,7 +18591,7 @@ def server_playlist_add_track(playlist_id):
 
             new_id = str(raw_playlist.ratingKey)
             logger.info(f"[ServerPlaylist] Added track to playlist, playlist ID: {new_id}")
-            _persist_find_and_add_match(source_track_id, active_server, track_id, server_track_title or new_item.title, source_title, source_artist)
+            _persist_find_and_add_match(source_track_id, active_server, track_id, server_track_title or new_item.title, source_title, source_artist, source_provider)
             return jsonify({"success": True, "message": "Track added", "new_playlist_id": new_id})
 
         elif active_server == 'jellyfin' and media_server_engine.client('jellyfin'):
@@ -18468,7 +18604,7 @@ def server_playlist_add_track(playlist_id):
             if plan['should_insert']:
                 new_track_objs = [type('T', (), {'ratingKey': tid, 'title': ''})() for tid in plan['new_ids']]
                 media_server_engine.client('jellyfin').update_playlist(playlist_name, new_track_objs)
-            _persist_find_and_add_match(source_track_id, active_server, track_id, server_track_title, source_title, source_artist)
+            _persist_find_and_add_match(source_track_id, active_server, track_id, server_track_title, source_title, source_artist, source_provider)
             return jsonify({"success": True, "message": "Track linked" if not plan['should_insert'] else "Track added"})
 
         elif active_server == 'navidrome' and media_server_engine.client('navidrome'):
@@ -18481,7 +18617,7 @@ def server_playlist_add_track(playlist_id):
             if plan['should_insert']:
                 new_track_objs = [type('T', (), {'ratingKey': tid, 'title': ''})() for tid in plan['new_ids']]
                 media_server_engine.client('navidrome').create_playlist(playlist_name, new_track_objs, playlist_id=playlist_id)
-            _persist_find_and_add_match(source_track_id, active_server, track_id, server_track_title, source_title, source_artist)
+            _persist_find_and_add_match(source_track_id, active_server, track_id, server_track_title, source_title, source_artist, source_provider)
             return jsonify({"success": True, "message": "Track linked" if not plan['should_insert'] else "Track added"})
 
         return jsonify({"success": False, "error": f"Unsupported server: {active_server}"}), 400
@@ -18685,8 +18821,12 @@ def mlm_save():
         db = get_database()
         profile_id = get_current_profile_id()
         # Validate library track exists before saving
-        if not db.api_get_tracks_by_ids([library_track_id]):
+        _lib_rows = db.api_get_tracks_by_ids([library_track_id])
+        if not _lib_rows:
             return jsonify({"success": False, "error": "Library track not found — it may have been removed"}), 400
+        # Store the file path so this match re-resolves after a rescan re-keys
+        # the track (#787) — same durability the Find & Add path gets.
+        _lib_file_path = (_lib_rows[0].get('file_path') or '') if _lib_rows else ''
         ok = mlm.save_match(
             db, profile_id, source, source_track_id, library_track_id,
             source_title=data.get('source_title', ''),
@@ -18694,6 +18834,7 @@ def mlm_save():
             source_album=data.get('source_album', ''),
             source_context_json=data.get('source_context_json', ''),
             server_source=data.get('server_source', ''),
+            library_file_path=_lib_file_path,
         )
         if not ok:
             return jsonify({"success": False, "error": "Failed to save match"}), 500
@@ -18739,6 +18880,10 @@ def start_missing_tracks_process(playlist_id):
     is_album_download = data.get('is_album_download', False)
     album_context = data.get('album_context', None)
     artist_context = data.get('artist_context', None)
+    # Issue #797 — per-request "Skip AcoustID verification" toggle from the
+    # album-download modal. Stored on the batch and propagated per-track by
+    # the master worker so AcoustID never quarantines this request's files.
+    skip_acoustid = bool(data.get('skip_acoustid', False))
 
     if not tracks:
         return jsonify({"success": False, "error": "No tracks provided"}), 400
@@ -18806,6 +18951,7 @@ def start_missing_tracks_process(playlist_id):
             'album_context': album_context,
             'artist_context': artist_context,
             'wing_it': wing_it,
+            'skip_acoustid': skip_acoustid,  # #797 per-request AcoustID bypass
             'batch_source': _downloads_history.detect_sync_source(playlist_id),
         }
 
@@ -21159,10 +21305,17 @@ def _get_source_playlist_states(states, error_label, info_log_label=None):
 def _submit_sync_task(sync_playlist_id, playlist_name, spotify_tracks, playlist_image_url):
     """Submit a sync to the shared executor (closes over sync_executor /
     _run_sync_task / get_current_profile_id so the lifted start_sync helper
-    stays free of those globals)."""
+    stays free of those globals).
+
+    Used by ALL per-source discovery syncs (Spotify-Public/Tidal/Deezer/Qobuz/
+    YouTube/iTunes-link/ListenBrainz/Beatport). These have no per-request mode
+    selector, so honor the configured default (Settings > Playlist sync mode) —
+    otherwise they always ran 'replace' regardless of the setting (#792)."""
+    from core.sync.playlist_edit import normalize_sync_mode
+    _mode = normalize_sync_mode(None, config_manager.get('playlist_sync.mode', 'replace'))
     return sync_executor.submit(
         _run_sync_task, sync_playlist_id, playlist_name, spotify_tracks,
-        None, get_current_profile_id(), playlist_image_url,
+        None, get_current_profile_id(), playlist_image_url, _mode,
     )
 
 
@@ -23260,6 +23413,12 @@ def update_youtube_discovery_match():
                             'confidence': 1.0,
                             'matched_data': matched_data,
                             'manual_match': True,
+                            # extra_data is MERGED on save, so explicitly clear
+                            # any stale stub/removal flags from before this fix —
+                            # otherwise a leftover wing_it_fallback would make the
+                            # pipeline re-discover and revert this manual pick.
+                            'wing_it_fallback': False,
+                            'unmatched_by_user': False,
                         }
                         db.update_mirrored_track_extra_data(db_track_id, extra_data)
                         result['matched_data'] = matched_data
@@ -23652,9 +23811,11 @@ def start_playlist_sync():
     # playlist — only adds tracks that aren't there yet. Per-server clients
     # implement append via native add APIs (Plex addItems, Jellyfin POST
     # /Playlists/<id>/Items, Navidrome updatePlaylist?songIdToAdd=...).
-    sync_mode = data.get('sync_mode', 'replace')
-    if sync_mode not in ('replace', 'append'):
-        sync_mode = 'replace'
+    # Per-request sync_mode wins; otherwise use the configured default
+    # (Settings > Playlist sync mode). Default 'replace' keeps today's behavior.
+    from core.sync.playlist_edit import normalize_sync_mode
+    sync_mode = normalize_sync_mode(data.get('sync_mode'),
+                                    config_manager.get('playlist_sync.mode', 'replace'))
 
     if not all([playlist_id, playlist_name, tracks_json]):
         return jsonify({"success": False, "error": "Missing playlist_id, name, or tracks."}), 400
@@ -34450,6 +34611,26 @@ def import_staging_suggestions():
 # WEBSOCKET (SOCKET.IO) EVENT HANDLERS AND BACKGROUND EMITTERS
 # ================================================================================================
 
+def _spotify_status_with_availability(spotify_status):
+    """Augment the spotify status dict with the Spotify-Free availability flags
+    the UI needs: ``metadata_available`` (search picker) and ``free_installed``
+    (Settings source selector — 'Spotify Free' is selectable when the package is
+    installed, since selecting it is the opt-in). Used by BOTH the /status
+    endpoint and the WebSocket status push so they never drift."""
+    out = dict(spotify_status or {})
+    try:
+        out['metadata_available'] = bool(
+            spotify_client and spotify_client.is_spotify_metadata_available())
+    except Exception:
+        out['metadata_available'] = bool(out.get('authenticated'))
+    try:
+        from core.spotify_free_metadata import spotify_free_installed
+        out['free_installed'] = spotify_free_installed()
+    except Exception:
+        out['free_installed'] = False
+    return out
+
+
 def _build_status_payload():
     """Build the same status payload used by GET /status, reading from the cache."""
     download_mode = config_manager.get('download_source.mode', 'hybrid')
@@ -34469,7 +34650,7 @@ def _build_status_payload():
 
     return {
         'metadata_source': metadata_status['metadata_source'],
-        'spotify': metadata_status['spotify'],
+        'spotify': _spotify_status_with_availability(metadata_status['spotify']),
         'media_server': _status_cache.get('media_server', {}),
         'soulseek': soulseek_data,
         'active_media_server': config_manager.get_active_media_server(),
@@ -34714,12 +34895,24 @@ from core.enrichment.services import (
 
 
 def _spotify_resume_pre_check():
-    """Mirror the inline Spotify rate-limit guard from the legacy
-    ``/api/spotify-enrichment/resume`` route. Returns
-    ``(429, message)`` to short-circuit when banned, ``None`` when ok."""
+    """Guard the Spotify enrichment worker's resume button against a rate-limit
+    ban. Returns ``(429, message)`` to short-circuit when banned, ``None`` ok.
+
+    Mirrors the worker's own loop: if the opt-in Spotify-Free fallback can
+    serve enrichment, allow resume and let the worker bridge via the no-creds
+    source during the ban. Block only when rate-limited AND nothing can serve
+    (plain auth, no free) — where resuming would just sleep.
+    """
     try:
         if _spotify_rate_limited():
-            return (429, 'Cannot resume while Spotify is rate limited')
+            from core.spotify_free_metadata import should_block_rate_limited_resume
+            try:
+                metadata_available = bool(spotify_client.is_spotify_metadata_available())
+            except Exception as e:
+                logger.debug("spotify free-availability check failed: %s", e)
+                metadata_available = False
+            if should_block_rate_limited_resume(True, metadata_available):
+                return (429, 'Cannot resume while Spotify is rate limited')
     except Exception as e:
         logger.debug("spotify rate-limit pre-check failed: %s", e)
     return None
@@ -34961,12 +35154,6 @@ def _emit_tool_progress_loop():
                 socketio.emit('tool:duplicate-cleaner', state_copy)
         except Exception as e:
             logger.debug(f"Error emitting duplicate cleaner status: {e}")
-        # Retag
-        try:
-            with retag_lock:
-                socketio.emit('tool:retag', dict(retag_state))
-        except Exception as e:
-            logger.debug(f"Error emitting retag status: {e}")
         # DB Update
         try:
             with db_update_lock:

webui/index.html

@@ -2201,6 +2201,19 @@
                                     </div>
                                 </div>
 
+                                <!-- Link lookup (#775): paste a provider link and resolve
+                                     it directly on the owning source (Spotify / Apple Music
+                                     / MusicBrainz / Deezer) — no fuzzy search. Results render
+                                     in the dropdown below and reuse the normal download/
+                                     import flow. Links only: a bare ID is ambiguous. -->
+                                <div class="enh-id-lookup">
+                                    <span class="enh-id-lookup-icon">🔗</span>
+                                    <input type="text" id="enh-id-input" class="enh-id-input"
+                                        placeholder="…or paste a Spotify / Apple Music / MusicBrainz / Deezer link"
+                                        autocomplete="off" spellcheck="false">
+                                    <button id="enh-id-btn" class="enh-id-btn" type="button">Look up</button>
+                                </div>
+
                                 <!-- Enhanced Search Dropdown (Overlay Panel) -->
                                 <div id="enhanced-dropdown" class="enhanced-dropdown hidden">
                                     <div class="enhanced-dropdown-content">
@@ -3825,6 +3838,7 @@
                                         <label>Primary metadata source:</label>
                                         <select id="metadata-fallback-source">
                                             <option value="spotify">Spotify</option>
+                                            <option value="spotify_free">Spotify Free (no credentials)</option>
                                             <option value="itunes">iTunes / Apple Music</option>
                                             <option value="deezer">Deezer</option>
                                             <option value="discogs">Discogs</option>
@@ -3832,7 +3846,13 @@
                                         </select>
                                     </div>
                                     <div class="callback-info">
-                                        <div class="callback-help">Choose the primary source for artist, album, and track metadata. Spotify can only be selected while an active Spotify session exists. Discogs requires a personal token. MusicBrainz is always available but rate-limited to 1 req/sec.</div>
+                                        <div class="callback-help">Where artist, album, and track metadata comes from:<br>
+                                            • <strong>Spotify</strong> — official Spotify; connect your account in the Spotify section below.<br>
+                                            • <strong>Spotify Free</strong> — the same Spotify catalog with no account needed. It's unofficial and best-effort (may break if Spotify changes its site), can't search albums by name (album results come from iTunes/Deezer instead), and can't read your personal library or playlists.<br>
+                                            • <strong>Deezer</strong> / <strong>iTunes</strong> — free, no account.<br>
+                                            • <strong>MusicBrainz</strong> — free, but limited to 1 request/sec.<br>
+                                            • <strong>Discogs</strong> — needs a personal access token.<br><br>
+                                            Tip: if you pick <strong>Spotify Free</strong> and later connect a real Spotify account, it uses the official account normally and only falls back to free while Spotify is rate-limited — then switches back automatically.</div>
                                     </div>
                                 </div>
 
@@ -6112,6 +6132,18 @@
                             <div class="settings-group" data-stg="library">
                                 <h3>Playlist Sync Settings</h3>
 
+                                <div class="form-group">
+                                    <label>Sync mode:</label>
+                                    <select id="playlist-sync-mode" class="form-select">
+                                        <option value="replace">Replace — recreate the playlist each sync (default)</option>
+                                        <option value="reconcile">Reconcile — edit in place, keep image &amp; description</option>
+                                        <option value="append">Append — only add new tracks, never remove</option>
+                                    </select>
+                                    <div class="help-text">
+                                        "Replace" deletes and recreates the server playlist every sync, which wipes its custom image/description. "Reconcile" updates the same playlist in place (adds new tracks, removes ones no longer in the source) so your custom image and description survive. "Append" only ever adds.
+                                    </div>
+                                </div>
+
                                 <div class="form-group">
                                     <label class="checkbox-label">
                                         <input type="checkbox" id="create-backup" checked>
@@ -6516,37 +6548,6 @@
                             </div>
                         </div>
 
-                        <div class="tool-card" id="metadata-updater-card">
-                            <div class="tool-card-header">
-                                <h4 class="tool-card-title">Metadata Updater</h4>
-                                <button class="tool-help-button" data-tool="metadata-updater"
-                                    title="Learn more about this tool">?</button>
-                            </div>
-                            <p class="metadata-updater-description tool-card-info">Updates artist photos, genres,
-                                and album art from Spotify.</p>
-                            <div class="tool-card-controls">
-                                <select id="metadata-refresh-interval">
-                                    <option value="180">6 months</option>
-                                    <option value="90">3 months</option>
-                                    <option value="30" selected>1 month</option>
-                                    <option value="14">2 weeks</option>
-                                    <option value="7">1 week</option>
-                                    <option value="0">Full refresh</option>
-                                </select>
-                                <button id="metadata-update-button">Begin Update</button>
-                            </div>
-                            <div class="tool-card-progress-section">
-                                <p class="progress-phase-label" id="metadata-phase-label">Current Artist: Not
-                                    running</p>
-                                <div class="progress-bar-container">
-                                    <div class="progress-bar-fill" id="metadata-progress-bar" style="width: 0%;">
-                                    </div>
-                                </div>
-                                <p class="progress-details-label" id="metadata-progress-label">0 / 0 artists (0.0%)
-                                </p>
-                            </div>
-                        </div>
-
                         <div class="tool-card" id="quality-scanner-card">
                             <div class="tool-card-header">
                                 <h4 class="tool-card-title">Quality Scanner</h4>
@@ -6590,6 +6591,43 @@
                             </div>
                         </div>
 
+                        <div class="tool-card" id="reconcile-ids-card">
+                            <div class="tool-card-header">
+                                <h4 class="tool-card-title">Import IDs from File Tags</h4>
+                                <button class="tool-help-button" data-tool="reconcile-ids"
+                                    title="Learn more about this tool">?</button>
+                            </div>
+                            <p class="tool-card-info">Read provider IDs (Spotify, MusicBrainz, iTunes, Deezer&hellip;) already embedded in your files and fill them into the database &mdash; lets enrichment workers skip redundant API lookups. Only fills blanks; never overwrites an existing match.</p>
+                            <div class="tool-card-stats">
+                                <div class="stat-item">
+                                    <span class="stat-item-label">IDs Filled:</span>
+                                    <span class="stat-item-value" id="reconcile-stat-filled">0</span>
+                                </div>
+                                <div class="stat-item">
+                                    <span class="stat-item-label">Rows Updated:</span>
+                                    <span class="stat-item-value" id="reconcile-stat-updated">0</span>
+                                </div>
+                                <div class="stat-item">
+                                    <span class="stat-item-label">Conflicts:</span>
+                                    <span class="stat-item-value" id="reconcile-stat-conflicts">0</span>
+                                </div>
+                                <div class="stat-item">
+                                    <span class="stat-item-label">Unreadable:</span>
+                                    <span class="stat-item-value" id="reconcile-stat-unreadable">0</span>
+                                </div>
+                            </div>
+                            <div class="tool-card-controls">
+                                <button id="reconcile-ids-button">Scan Library</button>
+                            </div>
+                            <div class="tool-card-progress-section">
+                                <p class="progress-phase-label" id="reconcile-phase-label">Ready to scan</p>
+                                <div class="progress-bar-container">
+                                    <div class="progress-bar-fill" id="reconcile-progress-bar" style="width: 0%;"></div>
+                                </div>
+                                <p class="progress-details-label" id="reconcile-progress-label">0 / 0 files scanned (0.0%)</p>
+                            </div>
+                        </div>
+
                         <div class="tool-card" id="duplicate-cleaner-card">
                             <div class="tool-card-header">
                                 <h4 class="tool-card-title">Duplicate Cleaner</h4>
@@ -6667,6 +6705,37 @@
                     <div class="tools-section">
                         <h3 class="tools-section-title">Metadata &amp; Cache</h3>
                         <div class="tools-grid">
+                        <div class="tool-card" id="metadata-updater-card">
+                            <div class="tool-card-header">
+                                <h4 class="tool-card-title">Metadata Updater</h4>
+                                <button class="tool-help-button" data-tool="metadata-updater"
+                                    title="Learn more about this tool">?</button>
+                            </div>
+                            <p class="metadata-updater-description tool-card-info">Updates artist photos, genres,
+                                and album art from Spotify.</p>
+                            <div class="tool-card-controls">
+                                <select id="metadata-refresh-interval">
+                                    <option value="180">6 months</option>
+                                    <option value="90">3 months</option>
+                                    <option value="30" selected>1 month</option>
+                                    <option value="14">2 weeks</option>
+                                    <option value="7">1 week</option>
+                                    <option value="0">Full refresh</option>
+                                </select>
+                                <button id="metadata-update-button">Begin Update</button>
+                            </div>
+                            <div class="tool-card-progress-section">
+                                <p class="progress-phase-label" id="metadata-phase-label">Current Artist: Not
+                                    running</p>
+                                <div class="progress-bar-container">
+                                    <div class="progress-bar-fill" id="metadata-progress-bar" style="width: 0%;">
+                                    </div>
+                                </div>
+                                <p class="progress-details-label" id="metadata-progress-label">0 / 0 artists (0.0%)
+                                </p>
+                            </div>
+                        </div>
+
 
                         <div class="tool-card" id="discovery-pool-card">
                             <div class="tool-card-header">
@@ -6707,45 +6776,6 @@
                                 <button onclick="openManualLibraryMatchTool()">Open Library Match</button>
                             </div>
                         </div>
-
-                        <div class="tool-card" id="retag-tool-card">
-                            <div class="tool-card-header">
-                                <h4 class="tool-card-title">Retag Tool</h4>
-                                <button class="tool-help-button" data-tool="retag-tool"
-                                    title="Learn more about this tool">?</button>
-                            </div>
-                            <p class="tool-card-info">Fix metadata on previously downloaded albums &amp; singles</p>
-                            <div class="tool-card-stats">
-                                <div class="stat-item">
-                                    <span class="stat-item-label">Groups:</span>
-                                    <span class="stat-item-value" id="retag-stat-groups">0</span>
-                                </div>
-                                <div class="stat-item">
-                                    <span class="stat-item-label">Tracks:</span>
-                                    <span class="stat-item-value" id="retag-stat-tracks">0</span>
-                                </div>
-                                <div class="stat-item">
-                                    <span class="stat-item-label">Artists:</span>
-                                    <span class="stat-item-value" id="retag-stat-artists">0</span>
-                                </div>
-                                <div class="stat-item">
-                                    <span class="stat-item-label">Status:</span>
-                                    <span class="stat-item-value" id="retag-stat-status">Idle</span>
-                                </div>
-                            </div>
-                            <div class="tool-card-controls">
-                                <button id="retag-open-button">Open Retag Tool</button>
-                            </div>
-                            <div class="tool-card-progress-section">
-                                <p class="progress-phase-label" id="retag-phase-label">Ready</p>
-                                <div class="progress-bar-container">
-                                    <div class="progress-bar-fill" id="retag-progress-bar" style="width: 0%;">
-                                    </div>
-                                </div>
-                                <p class="progress-details-label" id="retag-progress-label">0 / 0 tracks (0.0%)</p>
-                            </div>
-                        </div>
-
                     </div></div>
 
                     <!-- ── Management ── -->
@@ -7788,40 +7818,6 @@
 
     <!-- Tool Help Modal -->
     <!-- Retag Tool Modal -->
-    <div class="retag-modal-overlay" id="retag-modal">
-        <div class="retag-modal-container">
-            <div class="retag-modal-header">
-                <div class="retag-modal-header-left">
-                    <h2 class="retag-modal-title">Retag Tool</h2>
-                </div>
-                <div class="retag-header-actions">
-                    <button class="retag-clear-all-btn" id="retag-clear-all-btn" onclick="clearAllRetagGroups(this)">Clear All</button>
-                    <button class="retag-modal-close" onclick="closeRetagModal()">&times;</button>
-                </div>
-            </div>
-            <div class="retag-batch-bar" id="retag-batch-bar" style="display: none;">
-                <span class="retag-batch-count" id="retag-batch-count">0 selected</span>
-                <button class="retag-batch-remove-btn" onclick="batchRemoveRetagGroups()">Remove Selected</button>
-            </div>
-            <div class="retag-modal-body" id="retag-modal-body">
-                <div class="retag-loading">Loading downloads...</div>
-            </div>
-        </div>
-    </div>
-
-    <!-- Retag Search Sub-Modal -->
-    <div class="retag-search-overlay" id="retag-search-modal">
-        <div class="retag-search-container">
-            <div class="retag-search-header">
-                <h3 class="retag-search-title" id="retag-search-title">Search for Correct Album</h3>
-                <button class="retag-search-close" onclick="closeRetagSearch()">&times;</button>
-            </div>
-            <div class="retag-search-input-section">
-                <input type="text" id="retag-search-input" placeholder="Search albums..." autocomplete="off">
-            </div>
-            <div class="retag-search-results" id="retag-search-results"></div>
-        </div>
-    </div>
 
     <div class="tool-help-modal" id="tool-help-modal" onclick="if(event.target===this)closeToolHelpModal()">
         <div class="tool-help-modal-content">

webui/static/api-monitor.js

@@ -65,6 +65,14 @@ function _handleRateMonitorUpdate(data) {
     const grid = document.getElementById('rate-monitor-grid');
     if (!grid) return;
 
+    // Skip DOM writes while the equalizer is off-screen (you're on another page).
+    // All pages stay mounted, so updating a hidden grid still fires every
+    // MutationObserver on the document — including password-manager extensions
+    // that re-scan the WHOLE DOM on each mutation — for zero visible benefit.
+    // offsetParent is null when an ancestor is display:none. The next update that
+    // arrives while the dashboard is visible renders normally.
+    if (grid.offsetParent === null) return;
+
     // The dashboard rate monitor uses the equalizer-bar visual — a
     // vertical-bar VU-meter row that fits any service count without
     // an orphan grid cell. Detail page / mobile breakpoints keep the

webui/static/core.js

@@ -487,7 +487,6 @@ function initializeWebSocket() {
     socket.on('tool:stream', (data) => updateStreamStatusFromData(data));
     socket.on('tool:quality-scanner', (data) => updateQualityScanProgressFromData(data));
     socket.on('tool:duplicate-cleaner', (data) => updateDuplicateCleanProgressFromData(data));
-    socket.on('tool:retag', (data) => updateRetagStatusFromData(data));
     socket.on('tool:db-update', (data) => updateDbProgressFromData(data));
     socket.on('tool:metadata', (data) => updateMetadataStatusFromData(data));
     socket.on('tool:logs', (data) => updateLogsFromData(data));

webui/static/downloads.js

@@ -2451,6 +2451,11 @@ async function startMissingTracksProcess(playlistId) {
         const forceDownloadCheckbox = document.getElementById(`force-download-all-${playlistId}`);
         const forceDownloadAll = forceDownloadCheckbox ? forceDownloadCheckbox.checked : false;
 
+        // Issue #797 — per-request "Skip AcoustID verification" toggle. Absent
+        // checkbox (other call sites) → false, so behavior is unchanged there.
+        const skipAcoustidCheckbox = document.getElementById(`skip-acoustid-${playlistId}`);
+        const skipAcoustid = skipAcoustidCheckbox ? skipAcoustidCheckbox.checked : false;
+
         // Check if playlist folder mode toggle is enabled (only for sync page playlists)
         const playlistFolderMode = typeof isPlaylistOrganizeEnabled === 'function'
             ? isPlaylistOrganizeEnabled(playlistId)
@@ -2495,6 +2500,7 @@ async function startMissingTracksProcess(playlistId) {
             force_download_all: forceDownloadAll || isWingIt,
             ignore_manual_matches: forceDownloadAll,
             wing_it: isWingIt,
+            skip_acoustid: skipAcoustid,
         };
 
         // If this is an artist album download, use album name and include full context
@@ -4401,12 +4407,15 @@ async function startPlaylistSync(playlistId, syncModeOverride = null) {
     let syncMode = syncModeOverride;
     if (!syncMode) {
         const modeSelect = document.getElementById(`sync-mode-${playlistId}`);
-        syncMode = (modeSelect && modeSelect.value) || 'replace';
+        // Empty value = "use the Settings default" — send nothing so the
+        // backend falls back to playlist_sync.mode (#792). Don't hardcode
+        // 'replace' here or it shadows the global setting.
+        syncMode = (modeSelect && modeSelect.value) || '';
     }
-    if (syncMode !== 'replace' && syncMode !== 'append') {
-        syncMode = 'replace';
+    if (syncMode && !['replace', 'reconcile', 'append'].includes(syncMode)) {
+        syncMode = '';
     }
-    console.log(`🚀 [${new Date().toTimeString().split(' ')[0]}] Starting sync for playlist: ${playlistId} (mode: ${syncMode})`);
+    console.log(`🚀 [${new Date().toTimeString().split(' ')[0]}] Starting sync for playlist: ${playlistId} (mode: ${syncMode || 'default(setting)'})`);
     const playlist = spotifyPlaylists.find(p => p.id === playlistId);
     if (!playlist) {
         console.error(`❌ Could not find playlist data for ID: ${playlistId}`);

webui/static/enrichment-manager.js

@@ -274,6 +274,9 @@ async function _emPollSelected() {
 
 function _emStatusInfo(status) {
     if (!status || !status.enabled) return { cls: 'disabled', label: 'Disabled' };
+    // Rate-limited on the real API but still matching via the no-creds Spotify
+    // Free source — show as running, not stuck (#798 bridge).
+    if (status.using_free) return { cls: 'running', label: 'Running (Spotify Free)' };
     if (status.rate_limited) return { cls: 'ratelimited', label: 'Rate-limited' };
     if (status.paused) return { cls: 'paused', label: 'Paused' };
     if (status.idle) return { cls: 'idle', label: 'Idle' };
@@ -709,6 +712,9 @@ function _emUpdateHeaderLive() {
             cls += ' em-banner--warn';
             html = '⚙️ This source isn’t configured — add its credentials in Settings. '
                  + 'Browsing works, but matches and retries won’t run until it’s set up.';
+        } else if (status && status.using_free) {
+            // Real API banned but bridging via the no-creds Spotify Free source.
+            html = '✓ Spotify is rate-limited — matching via Spotify Free until the ban lifts.';
         } else if (status && status.rate_limited) {
             cls += ' em-banner--warn';
             const rl = status.rate_limit || {};

webui/static/enrichment.js

@@ -457,6 +457,10 @@ function updateSpotifyEnrichmentStatusFromData(data) {
 
     const notAuthenticated = data.authenticated === false;
     const isRateLimited = data.rate_limited === true;
+    // The real API is banned but the worker is still matching via the no-creds
+    // Spotify Free source — treat it as running, not stuck (#798 bridge).
+    const bridgingFree = data.using_free === true;
+    const rateLimitedStuck = isRateLimited && !bridgingFree;
     const budgetExhausted = data.daily_budget && data.daily_budget.exhausted;
 
     button.classList.remove('active', 'paused', 'complete', 'no-auth');
@@ -464,7 +468,7 @@ function updateSpotifyEnrichmentStatusFromData(data) {
         button.classList.add('paused');
     } else if (notAuthenticated) {
         button.classList.add('no-auth');
-    } else if (isRateLimited || budgetExhausted) {
+    } else if (rateLimitedStuck || budgetExhausted) {
         button.classList.add('paused');
     } else if (data.idle) {
         button.classList.add('complete');
@@ -479,7 +483,8 @@ function updateSpotifyEnrichmentStatusFromData(data) {
     if (tooltipStatus) {
         if (data.paused) { tooltipStatus.textContent = 'Paused'; }
         else if (notAuthenticated) { tooltipStatus.textContent = 'Not Authenticated'; }
-        else if (isRateLimited) { tooltipStatus.textContent = 'Rate Limited'; }
+        else if (rateLimitedStuck) { tooltipStatus.textContent = 'Rate Limited'; }
+        else if (bridgingFree) { tooltipStatus.textContent = 'Running (Spotify Free)'; }
         else if (budgetExhausted) { tooltipStatus.textContent = 'Daily Limit Reached'; }
         else if (data.idle) { tooltipStatus.textContent = 'Complete'; }
         else if (data.running) { tooltipStatus.textContent = 'Running'; }
@@ -491,10 +496,12 @@ function updateSpotifyEnrichmentStatusFromData(data) {
             tooltipCurrent.textContent = notAuthenticated ? 'Connect Spotify in Settings to enrich' : 'Click to resume';
         } else if (notAuthenticated) {
             tooltipCurrent.textContent = 'Connect Spotify in Settings to enrich';
-        } else if (isRateLimited) {
+        } else if (rateLimitedStuck) {
             const info = data.rate_limit || {};
             const remaining = info.remaining_seconds || 0;
             tooltipCurrent.textContent = remaining > 0 ? `Waiting ${Math.ceil(remaining / 60)}m for rate limit to clear` : 'Waiting for rate limit to clear';
+        } else if (bridgingFree && data.current_item && data.current_item.name) {
+            tooltipCurrent.textContent = `Now: ${data.current_item.name} (via Spotify Free)`;
         } else if (budgetExhausted) {
             const resets = data.daily_budget.resets_in_seconds || 0;
             const hours = Math.floor(resets / 3600);
@@ -2725,7 +2732,7 @@ async function loadRepairFindings() {
             duplicate_tracks: 'Duplicate', incomplete_album: 'Incomplete',
             path_mismatch: 'Path Mismatch', metadata_gap: 'Missing Metadata',
             missing_cover_art: 'Missing Art', track_number_mismatch: 'Track Number',
-            missing_lossy_copy: 'No Lossy Copy'
+            missing_lossy_copy: 'No Lossy Copy', library_retag: 'Re-tag'
         };
 
         // Finding types that have an automated fix action
@@ -2740,6 +2747,7 @@ async function loadRepairFindings() {
             missing_lossy_copy: 'Convert',
             acoustid_mismatch: 'Fix',
             missing_discography_track: 'Add to Wishlist',
+            library_retag: 'Apply Tags',
         };
 
         container.innerHTML = items.map(f => {
@@ -2905,6 +2913,40 @@ function _renderFindingDetail(f) {
             if (f.file_path) rows.push(['Full Path', f.file_path, 'path']);
             return _gridRows(rows) + _renderPlayButton(f);
 
+        case 'library_retag': {
+            const tracks = Array.isArray(d.tracks) ? d.tracks : [];
+            const changed = tracks.filter(t => t.changes && Object.keys(t.changes).length);
+            const meta = [];
+            if (d.source) meta.push(`Source: ${d.source}`);
+            if (d.mode) meta.push(`Mode: ${d.mode}`);
+            if (d.cover_action) meta.push(`Cover: ${d.cover_action}`);
+            let html = '';
+            if (meta.length) {
+                html += `<div class="repair-finding-meta" style="margin-bottom:8px">${_escFinding(meta.join('  ·  '))}</div>`;
+            }
+            if (!changed.length && d.cover_action) {
+                html += `<div class="repair-finding-desc">Tags already correct — this would refresh cover art only.</div>`;
+            }
+            // Per-track old → new diff (cap the rendered list so huge albums stay sane).
+            changed.slice(0, 40).forEach(t => {
+                const label = t.title || (t.file_path || '').split(/[\\/]/).pop();
+                const rows = Object.entries(t.changes).map(([field, c]) => [
+                    field.replace(/_/g, ' '),
+                    `${(c.old === '' || c.old == null) ? '∅' : c.old}   →   ${c.new}`,
+                    'highlight',
+                ]);
+                html += `<div style="margin:8px 0 2px;font-weight:600">${_escFinding(label)}</div>`;
+                html += _gridRows(rows);
+            });
+            if (changed.length > 40) {
+                html += `<div class="repair-finding-meta" style="margin-top:6px">…and ${changed.length - 40} more track(s)</div>`;
+            }
+            if (Array.isArray(d.unmatched) && d.unmatched.length) {
+                html += `<div class="repair-finding-meta" style="margin-top:8px">Unmatched (left untouched): ${_escFinding(d.unmatched.join(', '))}</div>`;
+            }
+            return html || '<div class="repair-finding-desc">No changes.</div>';
+        }
+
         case 'acoustid_mismatch': {
             let html = media + '<div style="margin-bottom:8px">';
             html += _renderScoreBar(d.fingerprint_score, 'Fingerprint');

webui/static/helper.js

@@ -3413,6 +3413,27 @@ function closeHelperSearch() {
 // projects that span multiple commits before shipping. Strip the flag at
 // release time and add a real `date:` line at the top of the version block.
 const WHATS_NEW = {
+    '2.6.7': [
+        { date: 'June 5, 2026 — 2.6.7 release' },
+        { title: 'Spotify Free — Spotify metadata with no credentials, and a rate-limit bridge (#798)', desc: 'a new "Spotify Free (no credentials)" metadata source. Pick it in Settings → Metadata to get Spotify search + enrichment without connecting a Spotify account (it uses the public web-player data via the optional spotapi package). It also works as a rate-limit bridge for connected users: if your real Spotify auth gets rate-limited, enrichment automatically falls through to the free source instead of stalling, then returns to your real auth once the ban lifts. The worker can be resumed mid-ban, the dashboard now shows "Running (Spotify Free)" instead of looking stuck, and the daily-API budget no longer blocks free work (it only ever capped real-API calls). Opt-in — nothing changes unless you select it.', page: 'settings' },
+        { title: 'Import IDs from File Tags — recover the provider IDs already in your files', desc: 'a new "Import IDs from File Tags" tool (Tools → Database & Scanning) reads the Spotify / iTunes / MusicBrainz / Deezer / Tidal / AudioDB / Genius / Last.fm IDs that SoulSync (or MusicBrainz Picard) already embedded in your files and fills them into the database. The media-server API never exposes these IDs, so the only way to get them is from the files themselves — and once they\'re in the DB, the enrichment workers skip every entity that already has an ID, saving a large amount of API traffic on an already-tagged library. Gap-fill only: it never overwrites an existing match, and it\'s atomically guarded so it can\'t clobber a match a worker makes at the same moment. New tracks also get this automatically as the final phase of every library scan, so it stays current without re-running the tool.', page: 'dashboard' },
+        { title: 'Library Re-tag — rewrite your library\'s tags from the source, safely', desc: 'a proper Library Re-tag job replaces the old Retag tool. It matches each file to its source tracklist and rewrites the tags — title, artist, album, track / disc numbers, cover art, and the embedded source IDs — and shows you a per-track old→new diff before anything is written. Standard dry-run pattern (you see exactly what would change and opt in to apply), Light / Full depth settings, and it pulls cover art + metadata from your configured source order.', page: 'dashboard' },
+        { title: 'Paste a metadata link to open an artist, album, or track (#775)', desc: 'the Search page now accepts a pasted metadata link. Paste a Spotify / iTunes / Deezer / etc. artist, album, or track URL and SoulSync resolves it and opens that exact item instead of running a name search — handy when a name search is ambiguous or you already have the link. Bare IDs are rejected as ambiguous (a link carries the entity type), and a clear not-found hint shows when nothing resolves.', page: 'search' },
+        { title: 'Mobile: a full responsive pass across the app (#793, #795)', desc: 'a comprehensive small-screen pass. The artist-detail page, enhanced track table, music player and Now Playing modal, sync buttons, discover carousels, the downloads page, the notification panel, and the mini-player all lay out cleanly on phones now, plus scroll-render and password-manager-extension compatibility improvements.' },
+        { title: 'Playlist sync: new "Reconcile" mode that edits in place (#792)', desc: 'playlist sync gains a "Reconcile" mode alongside Replace and Append. Replace deletes and recreates the server playlist every sync (which wipes its custom image / description); Reconcile updates the same playlist in place — adds new tracks, removes ones no longer in the source — so your custom image and description survive. Choose it per playlist in the sync-mode setting.', page: 'sync' },
+        { title: 'Manual album match now locks the edition it\'s pinned to (#758)', desc: 'manually matching an album now pins AND locks that exact edition. Previously the auto canonical resolver could drag a manually-matched regular edition back to the deluxe on the next cycle — reporting missing songs or renumbering tracks. The manual choice is now the authority every downstream tool reads (track-number repair, reorganize, missing-tracks), and the auto resolver won\'t override it. A new manual match still wins if you change your mind.', page: 'library' },
+        { title: 'Write Tags won\'t overwrite a correct file with placeholder data (#800)', desc: 'Write Tags will no longer stamp a correctly-tagged file with placeholder database values like "Various Artists" or "[Unknown Album]". If your file already holds a real value and the database only has a placeholder, the file\'s value is preserved instead of being destroyed. A legitimate value (including a genuine compilation\'s "Various Artists") still writes normally.', page: 'library' },
+        { title: 'AcoustID stops quarantining correct downloads of non-English artists (#797)', desc: 'AcoustID verification no longer false-quarantines correct downloads from non-English artists. When the fingerprint database returns the artist/title in its original script (e.g. Japanese kanji for Joe Hisaishi) and your metadata is romanized, the title can\'t match across scripts — so a correct file used to get quarantined. When the artist is confirmed across scripts via MusicBrainz aliases, the file is now kept instead of quarantined. A per-request "Skip AcoustID verification" toggle was also added to the download flow.', page: 'downloads' },
+        { title: 'Fix: wrong artist on the artist-detail page when a source ID was duplicated', desc: 'fixed a class of bugs where the artist-detail page could show the wrong artist, and where one enrichment worker could stamp a single source ID onto several different artists. Artist matching is tightened (a 0.85 confidence gate + a shared uniqueness guard), a one-time startup repair de-duplicates any source IDs shared across multiple artists, and the library view is kept when a source ID is ambiguous instead of jumping to the wrong artist.', page: 'library' },
+        { title: 'Fix: manual playlist fixes reverted on the next mirrored-sync run (#799)', desc: 'a manual fix on a mirrored playlist no longer reverts to "Wing It" on the next discovery / sync run — the manual match is checked first and its flag is cleared correctly. Also stopped the wide "Server Playlists" sync tab from stretching full-width.', page: 'sync' },
+        { title: 'Find & Add: manual matches now survive a library rescan (#787)', desc: 'a match made via Find & Add (and via the manual-match tool) now records a durable manual match plus the file path, so it survives a library rescan instead of being lost and re-flagged.' },
+        { title: 'Fix: streamed tracks played with no sound', desc: 'fixed streamed tracks occasionally playing silently — the browser\'s Web Audio context could be left suspended. It\'s now resumed on the play event across every play path.', page: 'dashboard' },
+        { title: 'Navidrome: respect the selected music library + survive renames (#789)', desc: 'Navidrome now respects the music library you selected (it previously ignored the selection and imported all libraries), and pins that selection by id rather than name so it survives a library rename.', page: 'settings' },
+        { title: 'Fix: file / CSV playlists failed to match raw "Artist - Title" titles (#785)', desc: 'file and CSV playlists whose rows are raw "Artist - Title" strings now match correctly — the discovery worker also searches the canonical title form.', page: 'sync' },
+        { title: 'Fix: torrent client URL without http:// failed to connect (#790)', desc: 'a torrent client URL entered without an http:// or https:// scheme now connects instead of failing the connection probe.', page: 'settings' },
+        { title: 'Fix: Soulseek album bundle left completed files in the slskd folder (#796)', desc: 'Soulseek album-bundle downloads no longer leave their completed copies behind in the slskd download folder after the bundle finishes.', page: 'downloads' },
+        { title: 'Cover Art Filler + Library Re-tag honor your configured cover-art sources', desc: 'both the Cover Art Filler and the new Library Re-tag job now pull artwork from your configured cover-art source order instead of a fixed path, so the cover you get matches your source preferences.', page: 'dashboard' },
+    ],
     '2.6.6': [
         { date: 'June 3, 2026 — 2.6.6 release' },
         { title: 'Fix: qBittorrent 5.2.0+ would not connect (HTTP 204 login)', desc: 'qBittorrent 5.2.0 changed its /api/v2/auth/login endpoint to answer a successful login with HTTP 204 (No Content) instead of the old HTTP 200 + "Ok." body. SoulSync required the literal "Ok." response, so on 5.2.0+ every login failed with "HTTP 204 body=" — the connection probe and all torrent actions were dead even though qBittorrent itself logged a successful login. Login is now accepted on the SID auth cookie and/or a success response (the old "Ok." or the new empty 204), while bad credentials (which qBittorrent reports as HTTP 200 + "Fails.") are still rejected. Covers 5.2.0 / 5.2.1; no more whitelist-bypass workaround needed.', page: 'settings' },
@@ -3572,6 +3593,63 @@ const WHATS_NEW = {
 // Section shape: { title, description, features: [bullet strings],
 //                  usage_note?: 'optional hint shown at the bottom' }
 const VERSION_MODAL_SECTIONS = [
+    {
+        title: "Spotify Free — metadata with no credentials (#798)",
+        description: "a new \"Spotify Free\" metadata source that uses Spotify's public web-player data, so you can get Spotify search + enrichment without connecting an account. For connected users it also bridges rate-limit bans automatically — when your real auth is rate-limited, enrichment keeps running through the free source instead of stalling, then returns to your real auth once the ban lifts.",
+        features: [
+            "pick \"Spotify Free (no credentials)\" in Settings → Metadata to use it without a Spotify account",
+            "automatic rate-limit bridge for connected users — no more enrichment stalling out during a ban",
+            "the worker resumes mid-ban, the dashboard shows \"Running (Spotify Free)\" instead of looking stuck",
+            "the daily-API budget no longer blocks free work — it only ever capped real-API calls",
+            "opt-in; requires the optional spotapi package",
+        ],
+        usage_note: "Settings → Metadata → Spotify Free",
+    },
+    {
+        title: "Import IDs from File Tags",
+        description: "your files often already carry the Spotify / MusicBrainz / iTunes / Deezer IDs that SoulSync (or MusicBrainz Picard) embedded when they were tagged — but the media-server scan can't see them. This tool reads them straight from the files into the database, so the enrichment workers can skip those lookups entirely. On an already-tagged library that's a large amount of saved API traffic.",
+        features: [
+            "reads embedded Spotify / iTunes / MusicBrainz / Deezer / Tidal / AudioDB / Genius / Last.fm IDs into the DB",
+            "gap-fill only — never overwrites an existing match, and atomically guarded against races",
+            "new tracks also get it automatically as the final phase of every library scan",
+            "enrichment workers skip any entity that already has an ID, so this directly cuts API calls",
+        ],
+        usage_note: "Tools → Database & Scanning → Import IDs from File Tags",
+    },
+    {
+        title: "Library Re-tag",
+        description: "a proper Library Re-tag job (replacing the old Retag tool): it matches each file to its source tracklist and rewrites the tags — title, artist, album, track / disc numbers, cover art, and the embedded source IDs — and shows a per-track old→new diff so you can review before anything is written.",
+        features: [
+            "per-track old→new diff in the finding card before you apply",
+            "standard dry-run pattern — see what would change, then opt in to apply",
+            "Light / Full depth settings; cover art + metadata pulled from your configured source order",
+            "writes the embedded source IDs too, so re-tagged files survive future scans",
+        ],
+        usage_note: "Dashboard → Manage Workers → Library Re-tag",
+    },
+    {
+        title: "Paste a metadata link to open it (#775)",
+        description: "the Search page now takes a pasted metadata link. Drop in a Spotify / iTunes / Deezer artist, album, or track URL and SoulSync opens that exact item instead of running a name search — perfect when a name search is ambiguous or you already have the link.",
+        features: [
+            "paste an artist / album / track URL → opens the exact item",
+            "bare IDs are rejected as ambiguous (a link carries the entity type)",
+            "clear not-found hint when nothing resolves",
+        ],
+        usage_note: "Search page",
+    },
+    {
+        title: "Recent Fixes & Polish (2.6.7)",
+        description: "a stack of fixes and refinements that shipped alongside the headline features.",
+        features: [
+            "Manual album match now LOCKS the edition it's pinned to (#758) — the auto resolver can't drag it back to the deluxe",
+            "Write Tags won't overwrite a correct file with placeholder data like \"Various Artists\" / \"[Unknown Album]\" (#800)",
+            "AcoustID stops false-quarantining correct downloads of non-English artists (#797)",
+            "full mobile / small-screen responsive pass across the app (#793, #795)",
+            "new \"Reconcile\" playlist sync mode that edits in place and keeps your custom image / description (#792)",
+            "fixes: wrong artist on duplicated source IDs, manual fixes reverting on mirrored sync (#799), Find & Add matches surviving rescans (#787), Navidrome library selection (#789), silent streamed tracks, torrent URL without scheme (#790), file/CSV playlist matching (#785)",
+        ],
+        usage_note: "browse the What's New panel for the full 2.6.7 changelog",
+    },
     {
         title: "Artist Map, Reimagined",
         description: "the Discover artist map got a full rework — it now reads like a living constellation of your library instead of a flat blob. Explore one genre island at a time, watch bubbles bloom into place, and open a side panel with everything about the artist under your cursor.",

webui/static/media-player.js

@@ -23,6 +23,11 @@ function initializeMediaPlayer() {
         audioPlayer.addEventListener('error', onAudioError);
         audioPlayer.addEventListener('loadstart', onAudioLoadStart);
         audioPlayer.addEventListener('canplay', onAudioCanPlay);
+        // Universal: once the visualizer routes this element through
+        // npAudioContext, the element is silent while that context is
+        // suspended. The 'play' event fires on EVERY playback start (every
+        // code path, incl. ones that bypass setPlayingState), so resume here.
+        audioPlayer.addEventListener('play', npEnsureAudioContextRunning);
 
         // Set initial volume — restore the saved level (Spotify-style), else 70%.
         const _savedVol = npLoadSavedVolume();
@@ -2661,6 +2666,20 @@ function getNpAlbumArtUrl() {
 // WEB AUDIO VISUALIZER
 // ===============================
 
+// Once createMediaElementSource() captures the <audio> element, ALL of its
+// output is routed through this AudioContext — so if the context is suspended
+// (browsers create it suspended under the autoplay policy, and we init it from
+// an async play().then callback that's outside the gesture), the track plays
+// but no sound reaches the speakers. Resuming must happen on every play start,
+// not only when the visualizer loop runs. Safe to call anytime.
+function npEnsureAudioContextRunning() {
+    try {
+        if (npAudioContext && npAudioContext.state === 'suspended') {
+            npAudioContext.resume().catch(() => {});
+        }
+    } catch (_) { /* no-op */ }
+}
+
 function npInitVisualizer() {
     if (npVizInitialized || !audioPlayer) return;
     try {
@@ -2676,6 +2695,9 @@ function npInitVisualizer() {
             npAnalyser.connect(npAudioContext.destination);
         }
         npVizInitialized = true;
+        // Freshly created contexts start suspended — resume so the rerouted
+        // element is actually audible (this is the no-sound-on-play bug).
+        npEnsureAudioContextRunning();
     } catch (e) {
         console.warn('Web Audio visualizer init failed, using CSS fallback:', e.message);
         // Mark as CSS fallback

webui/static/mobile.css

@@ -109,7 +109,8 @@
     }
 
     #artist-hero-section #artist-detail-image {
-        width: 100% !important
+        width: 100% !important;
+        max-width: none !important;
     }
 
     #media-player {
@@ -127,6 +128,7 @@
         width: 100%;
         flex-direction: row;
         flex-wrap: wrap;
+        justify-content: center;
     }
 
     .enh-compact-item.artist-card {
@@ -1039,22 +1041,16 @@
         gap: 16px;
     }
 
-    .artist-image-container {
-        width: 100px;
-        height: 100px;
-    }
-
     .artist-image,
     .artist-image-fallback {
         width: 100px;
         height: 100px;
     }
 
-    .artist-info h1,
-    .artist-name {
-        font-size: 24px !important;
-        white-space: normal;
+    .artist-hero-section .artist-name {
+        font-size: 1.6em;
         text-align: center;
+        display: block;
     }
 
     .artist-hero-badges {
@@ -1076,7 +1072,7 @@
     .artist-hero-bio {
         font-size: 12px;
         -webkit-line-clamp: 3;
-        max-height: 54px;
+        max-height: fit-content;
     }
 
     .artist-hero-numbers {
@@ -1186,7 +1182,7 @@
     }
 
     .discover-card {
-        width: 160px;
+        width: 45%;
     }
 
     /* Horizontal scroll tabs */
@@ -3079,10 +3075,14 @@
 
     /* Notification panel */
     .notif-panel {
-        width: calc(100vw - 24px);
-        max-width: 100%;
-        right: 12px;
-        bottom: 62px;
+        /* JS positions this inline from the bell's rect (right/bottom), which on
+           mobile pushes it off-screen (the bell isn't flush right). Override the
+           inline styles with !important and anchor both sides so it always fits. */
+        left: 12px !important;
+        right: 12px !important;
+        width: auto !important;
+        max-width: none !important;
+        bottom: 62px !important;
         max-height: 55vh;
         border-radius: 14px;
     }
@@ -3190,9 +3190,10 @@
     }
 
     .notif-panel {
-        right: 8px;
-        width: calc(100vw - 16px);
-        bottom: 54px;
+        left: 8px !important;
+        right: 8px !important;
+        width: auto !important;
+        bottom: 54px !important;
     }
 }
 
@@ -3310,3 +3311,225 @@
         padding: 9px 12px;
     }
 }
+
+/* ============================================================================
+   Mobile fixes (v2) — phone-only, all inside max-width:768px. Desktop untouched.
+   ============================================================================ */
+@media (max-width: 768px) {
+    /* Center the artist hero action buttons + match-status chips on phone
+       (moved here from the base rule so desktop stays left-aligned). */
+    .artist-hero-actions { justify-content: center; }
+    .enhanced-match-status-row { justify-content: center; }
+
+    /* #8 Page-container heroes carry desktop-sized padding/margins that waste
+       space and look off on a phone. Tighten them up. */
+    .tools-maintenance-hero,
+    .watchlist-artist-config-hero,
+    .watchlist-detail-hero,
+    .discover-hero {
+        padding: 14px 14px;
+        margin-bottom: 16px;
+    }
+
+    /* #9 Sync page header: title + the three action buttons (Auto-Sync / Library
+       Match / Sync History) don't fit side-by-side. Stack the header and let the
+       buttons wrap so all three are reachable. */
+    .sync-header-row {
+        flex-direction: column;
+        align-items: stretch;
+        gap: 12px;
+    }
+    .sync-header-row > div:last-child {
+        flex-wrap: wrap;
+    }
+    .sync-header-row .sync-history-btn {
+        flex: 1 1 auto;
+    }
+}
+
+@media (max-width: 768px) {
+    /* #6 Enhanced-view track table: a 6+ column table can't fit a phone and the
+       panel clips the overflow, so only the first column showed. Drop table
+       layout entirely and make each row a single flex line: play · title (takes
+       the space) · duration · the ⋯ actions button. Secondary columns hidden. */
+    .enhanced-track-table,
+    .enhanced-track-table thead,
+    .enhanced-track-table tbody,
+    .enhanced-track-table tr,
+    .enhanced-track-table td,
+    .enhanced-track-table th {
+        display: block;
+        width: auto;
+    }
+    .enhanced-track-table thead { display: none; }
+    .enhanced-track-table tr {
+        display: flex;
+        align-items: center;
+        gap: 10px;
+        padding: 8px 6px;
+        border-bottom: 1px solid rgba(255, 255, 255, 0.05);
+    }
+    .enhanced-track-table td,
+    .enhanced-track-table th {
+        padding: 0;
+        border: none;
+        white-space: normal;
+    }
+    .enhanced-track-table .col-play {
+        flex: 0 0 auto;
+        width: auto;
+    }
+    .enhanced-track-table .col-title {
+        flex: 1 1 auto;
+        min-width: 0;
+        word-break: break-word;
+        font-size: 13px;
+    }
+    .enhanced-track-table .col-duration {
+        flex: 0 0 auto;
+        width: auto;
+        font-size: 11px;
+        opacity: 0.65;
+    }
+    .enhanced-track-table .col-mobile-actions {
+        display: block;
+        flex: 0 0 auto;
+        width: auto;
+        text-align: right;
+    }
+    /* Everything else folds into the ⋯ actions sheet — hide on the row. */
+    .enhanced-track-table .col-num,
+    .enhanced-track-table .col-disc,
+    .enhanced-track-table .col-format,
+    .enhanced-track-table .col-bitrate,
+    .enhanced-track-table .col-bpm,
+    .enhanced-track-table .col-path,
+    .enhanced-track-table .col-match,
+    .enhanced-track-table .col-queue,
+    .enhanced-track-table .col-writetag,
+    .enhanced-track-table .col-delete,
+    .enhanced-track-table .col-report,
+    .enhanced-track-table tr > th:first-child {
+        display: none;
+    }
+}
+
+@media (max-width: 768px) {
+    /* #7 Mini media player: on desktop it's a 340px widget pinned bottom-right
+       (right:132px) — that overflows a phone and overlaps the bottom search.
+       Make it a full-width bar that sits just ABOVE the global search bar
+       (which is at bottom:16px, height:38px on mobile). */
+    .media-player {
+        left: 10px;
+        right: 10px;
+        width: auto;
+        bottom: 62px;
+        margin: 0;
+    }
+}
+
+@media (max-width: 768px) {
+    /* ── Now Playing modal — full responsive pass ──
+       Desktop is a two-column (art | controls) layout with heavy 40-48px
+       padding. Existing mobile rules made it full-screen + stacked the body but
+       left the panels' desktop padding and the controls/queue/lyrics untouched. */
+    .np-body {
+        padding: 24px 16px 28px;
+        gap: 20px;
+    }
+    .np-left,
+    .np-right {
+        width: 100%;
+    }
+    /* Album art scales with the screen instead of a fixed 220px. */
+    .np-album-art-container {
+        width: min(220px, 66vw);
+        height: auto;
+        aspect-ratio: 1 / 1;
+        margin: 0 auto;
+    }
+    .np-track-info { text-align: center; }
+    .np-action-buttons { justify-content: center; }
+    .np-util-row { justify-content: center; flex-wrap: wrap; }
+    /* Playback controls: tighten the gap so the row fits a phone. */
+    .np-controls-row { gap: 12px; justify-content: center; }
+    /* Queue + lyrics panels: drop the 40px desktop side padding that crushed
+       content on a narrow screen; give them a bit more vertical room. */
+    .np-queue-panel { padding: 0 16px 16px; }
+    .np-lyrics-panel { padding: 0 16px; }
+    .np-queue-body { max-height: 240px; }
+    .np-lyrics-body { max-height: 300px; }
+}
+
+/* When the expanded Now Playing modal is open, hide the floating mini-player —
+   it has a higher z-index (99998) than the modal overlay (10001), so it would
+   otherwise float on top of the modal's content. Both are body-level siblings
+   (#media-player follows #np-modal-overlay), and the overlay drops its .hidden
+   class when open. Not width-scoped — applies on desktop too. */
+.np-modal-overlay:not(.hidden) ~ #media-player {
+    display: none !important;
+}
+
+@media (max-width: 768px) {
+    /* Recommended-artist carousel cards → 2-up wrap on mobile. The base rule
+       pins them with flex:0 0 160px, which overrides plain width — so override
+       the flex-basis too for the 45% to take. */
+    .recommended-card--carousel {
+        flex: 0 0 45%;
+        width: 45%;
+    }
+}
+
+@media (max-width: 768px) {
+    /* ── Downloads page (.adl-*) ──
+       Had ZERO mobile rules. Desktop is a two-column layout: the main list
+       (.adl-main, flex:1) + a fixed 366px batch panel with a left border that
+       scrolls independently. On a phone that doesn't fit — stack it. */
+    .adl-layout {
+        flex-direction: column;
+        gap: 16px;
+    }
+    .adl-batch-panel {
+        width: 100%;
+        flex-shrink: 1;
+        border-left: none;
+        border-top: 1px solid rgba(255, 255, 255, 0.06);
+        padding: 14px 4px 0;
+        overflow-y: visible;        /* grows in the page flow instead of own scroll */
+    }
+
+    /* Header: title + controls sat in one row; stack so the pills get full width. */
+    .adl-header {
+        flex-direction: column;
+        align-items: stretch;
+        gap: 10px;
+    }
+    .adl-title { font-size: 1.3rem; }
+    .adl-controls {
+        flex-direction: column;
+        align-items: stretch;
+        gap: 8px;
+    }
+    /* Filter pills (All / Active / Queued / Completed / Failed) + count +
+       Cancel All / Clear Completed: wrap instead of overflowing off-screen. */
+    .adl-filter-pills {
+        flex-wrap: wrap;
+        justify-content: flex-start;
+    }
+    .adl-pill { padding: 6px 12px; }
+    /* Action buttons full-width-friendly so they're tappable. */
+    .adl-cancel-all-btn,
+    .adl-clear-btn { flex: 1 1 auto; }
+}
+
+@media (max-width: 768px) {
+    /* Sidebar visualizer is pinned at the (desktop) sidebar's right edge, so on
+       mobile it floats over the page content when the off-canvas sidebar drawer
+       is closed. Show it ONLY while the drawer is open. The .active/.viz-* rules
+       set display with 2-class specificity, so this 3-class + !important selector
+       is needed to beat them; when the drawer IS open it doesn't match, so the
+       visualizer's normal display rules take over again. */
+    .sidebar:not(.mobile-open) ~ .sidebar-visualizer {
+        display: none !important;
+    }
+}

webui/static/pages-extra.js

@@ -1066,18 +1066,24 @@ function explorerFitToView() {
     });
 }
 
-// Scroll wheel zoom (no modifier needed inside viewport)
-document.addEventListener('wheel', (e) => {
+// Scroll wheel zoom (no modifier needed inside viewport).
+// IMPORTANT: attach to the viewport element, NOT document. A non-passive wheel
+// listener on document disables the browser's compositor (async) scrolling for
+// the ENTIRE app — every wheel/trackpad scroll then runs through the main thread.
+// Scoping it to the viewport keeps zoom working while the rest of the app keeps
+// smooth compositor scrolling.
+(function attachExplorerWheelZoom() {
     const viewport = document.getElementById('explorer-viewport');
-    if (!viewport || !viewport.contains(e.target)) return;
-    // Check if we're on the explorer page
-    const page = document.getElementById('playlist-explorer-page');
-    if (!page || !page.classList.contains('active')) return;
+    if (!viewport) return;
+    viewport.addEventListener('wheel', (e) => {
+        const page = document.getElementById('playlist-explorer-page');
+        if (!page || !page.classList.contains('active')) return;
 
-    e.preventDefault();
-    const step = e.deltaY > 0 ? -0.08 : 0.08;
-    explorerZoom(step);
-}, { passive: false });
+        e.preventDefault();
+        const step = e.deltaY > 0 ? -0.08 : 0.08;
+        explorerZoom(step);
+    }, { passive: false });
+})();
 
 // Middle-click / right-click drag to pan
 document.addEventListener('mousedown', (e) => {
@@ -1836,6 +1842,9 @@ async function _serverSelectTrack(trackIndex, mode, newTrackId, el) {
                     source_track_id: srcTrack.source_track_id || '',
                     source_title: srcTrack.name || '',
                     source_artist: srcTrack.artist || '',
+                    // Provider of the source track, so the durable manual match
+                    // (#787) records the right source. Retrieval is source-agnostic.
+                    source: srcTrack.source || _serverEditorState.mirroredPlaylist?.source || '',
                 })
             });
         }

webui/static/search.js

@@ -271,6 +271,79 @@ function initializeSearchModeToggle() {
         });
     }
 
+    // ── Link / ID lookup (#775) ──────────────────────────────────────
+    // Paste a provider link or bare ID; the backend resolves it directly
+    // on the owning source (no fuzzy search) and returns the single hit
+    // plus that source. We adopt the resolved source as the active one so
+    // the existing album re-fetch + download/import flow routes correctly,
+    // then render through the same dropdown path as a normal search.
+    const idInput = document.getElementById('enh-id-input');
+    const idBtn = document.getElementById('enh-id-btn');
+
+    async function submitIdLookup() {
+        if (!idInput) return;
+        const raw = idInput.value.trim();
+        if (!raw) return;
+
+        // Show the controller's loading UI while resolving.
+        if (loadingState) {
+            loadingState.classList.remove('hidden');
+            const loadingText = document.getElementById('enhanced-loading-text');
+            if (loadingText) loadingText.textContent = 'Resolving link…';
+        }
+        if (emptyState) emptyState.classList.add('hidden');
+        if (resultsContainer) resultsContainer.classList.add('hidden');
+        showDropdown();
+
+        let data;
+        try {
+            const resp = await fetch('/api/enhanced-search/by-id', {
+                method: 'POST',
+                headers: { 'Content-Type': 'application/json' },
+                body: JSON.stringify({ query: raw }),
+            });
+            data = await resp.json();
+        } catch (err) {
+            console.error('Link/ID lookup failed:', err);
+            if (loadingState) loadingState.classList.add('hidden');
+            if (typeof showToast === 'function') showToast('Link/ID lookup failed.', 'error');
+            return;
+        }
+
+        if (data && data.available && data.source) {
+            // Adopt the resolving source as active, seed its cache with the
+            // single hit, and render via the shared state-driven path.
+            searchController.state.activeSource = data.source;
+            searchController.state.query = raw;
+            searchController.state.sources[data.source] = {
+                db_artists: [],
+                artists: data.artists || [],
+                albums: data.albums || [],
+                tracks: data.tracks || [],
+            };
+            if (typeof searchController.renderSourceRow === 'function') {
+                searchController.renderSourceRow();
+            }
+            _renderFromState(searchController.state);
+        } else {
+            // Not a link, or nothing resolved — surface the backend's hint
+            // via a toast (non-destructive) and show the empty state.
+            if (loadingState) loadingState.classList.add('hidden');
+            if (resultsContainer) resultsContainer.classList.add('hidden');
+            if (emptyState) emptyState.classList.remove('hidden');
+            showDropdown();
+            const msg = (data && data.message) || 'No match for that link.';
+            if (typeof showToast === 'function') showToast(msg, 'warning');
+        }
+    }
+
+    if (idBtn) idBtn.addEventListener('click', submitIdLookup);
+    if (idInput) {
+        idInput.addEventListener('keypress', (e) => {
+            if (e.key === 'Enter') submitIdLookup();
+        });
+    }
+
     // Close button inside dropdown (mobile)
     const dropdownCloseBtn = document.getElementById('enhanced-dropdown-close');
     if (dropdownCloseBtn) {

webui/static/settings.js

@@ -64,8 +64,14 @@ function syncMetadataSourceSelection(source) {
 
 function _isMetadataSourceSelectable(source) {
     if (source === 'spotify') {
+        // Official Spotify needs a connected session.
         return _lastStatusPayload?.spotify?.authenticated === true;
     }
+    if (source === 'spotify_free') {
+        // No-creds Spotify only needs the SpotipyFree package installed —
+        // selecting it IS the opt-in, so it must NOT depend on having selected it.
+        return _lastStatusPayload?.spotify?.free_installed === true;
+    }
     if (source === 'discogs') {
         const token = document.getElementById('discogs-token');
         return !!token?.value?.trim();
@@ -143,6 +149,25 @@ function handleMetadataSourceChange(event) {
 }
 
 let _settingsInitialized = false;
+// Tell password-manager extensions (Bitwarden / 1Password / LastPass) to ignore
+// this app's credential inputs. The settings page is full of API-key / token /
+// secret fields; password managers treat them as login forms and re-scan the
+// whole (large, constantly-mutating) DOM on every change, which can peg the main
+// thread for seconds. These attributes make them skip the fields entirely.
+function _markCredentialFieldsNoAutofill(root) {
+    const scope = root || document;
+    scope.querySelectorAll('input, textarea').forEach((el) => {
+        if (el.dataset.bwignore !== undefined) return; // already tagged
+        el.setAttribute('data-bwignore', '');          // Bitwarden
+        el.setAttribute('data-1p-ignore', '');         // 1Password
+        el.setAttribute('data-lpignore', 'true');      // LastPass
+        if (!el.getAttribute('autocomplete')) el.setAttribute('autocomplete', 'off');
+    });
+}
+// Run once on load (inputs exist from page load — all pages are mounted).
+if (document.readyState !== 'loading') _markCredentialFieldsNoAutofill();
+else document.addEventListener('DOMContentLoaded', () => _markCredentialFieldsNoAutofill());
+
 function initializeSettings() {
     // This function is called when the settings page is loaded.
     // It attaches event listeners to all interactive elements on the page.
@@ -151,6 +176,9 @@ function initializeSettings() {
     if (_settingsInitialized) return;
     _settingsInitialized = true;
 
+    // Re-tag in case any inputs were added dynamically since page load.
+    _markCredentialFieldsNoAutofill(document.getElementById('settings-page'));
+
     // Accent color listeners (live preview + custom picker toggle)
     initAccentColorListeners();
 
@@ -1021,8 +1049,13 @@ async function loadSettingsData() {
         // Populate Discogs settings
         document.getElementById('discogs-token').value = settings.discogs?.token || '';
 
-        // Populate Metadata source setting
-        document.getElementById('metadata-fallback-source').value = settings.metadata?.fallback_source || 'deezer';
+        // Populate Metadata source setting. 'Spotify Free' is stored as
+        // fallback_source='spotify' + spotify_free=true (so all downstream
+        // 'spotify' routing is unchanged) — map it back to the dropdown value.
+        const _fbSrc = settings.metadata?.fallback_source || 'deezer';
+        const _metaSel = (_fbSrc === 'spotify' && settings.metadata?.spotify_free === true)
+            ? 'spotify_free' : _fbSrc;
+        document.getElementById('metadata-fallback-source').value = _metaSel;
 
         // Populate Hydrabase settings
         const hbConfig = settings.hydrabase || {};
@@ -1175,6 +1208,8 @@ async function loadSettingsData() {
 
         // Populate Playlist Sync settings
         document.getElementById('create-backup').checked = settings.playlist_sync?.create_backup !== false;
+        const _syncModeEl = document.getElementById('playlist-sync-mode');
+        if (_syncModeEl) _syncModeEl.value = settings.playlist_sync?.mode || 'replace';
 
         // Populate Post-Download Conversion settings
         document.getElementById('downsample-hires').checked = settings.lossy_copy?.downsample_hires === true;
@@ -2731,12 +2766,19 @@ async function saveSettings(quiet = false) {
     const discogsTokenPresent = !!discogsTokenInput?.value?.trim();
     let metadataSource = metadataSourceSelect?.value || 'deezer';
     const spotifySessionActive = _lastStatusPayload?.spotify?.authenticated === true;
+    const spotifyFreeInstalled = _lastStatusPayload?.spotify?.free_installed === true;
     if (metadataSource === 'spotify' && !spotifySessionActive) {
         metadataSource = _metadataSourceFallback('spotify');
         if (metadataSourceSelect) metadataSourceSelect.value = metadataSource;
         if (!quiet) {
             showToast('Spotify is disconnected, so the primary metadata source was switched.', 'warning');
         }
+    } else if (metadataSource === 'spotify_free' && !spotifyFreeInstalled) {
+        metadataSource = _metadataSourceFallback('spotify_free');
+        if (metadataSourceSelect) metadataSourceSelect.value = metadataSource;
+        if (!quiet) {
+            showToast('Spotify Free needs the SpotipyFree package installed.', 'warning');
+        }
     } else if (metadataSource === 'discogs' && !discogsTokenPresent) {
         metadataSource = _metadataSourceFallback('discogs');
         if (metadataSourceSelect) metadataSourceSelect.value = metadataSource;
@@ -2818,7 +2860,10 @@ async function saveSettings(quiet = false) {
             token: document.getElementById('discogs-token').value,
         },
         metadata: {
-            fallback_source: metadataSource
+            // 'Spotify Free' is stored as the spotify source + a flag, so all
+            // downstream 'spotify' routing is unchanged.
+            fallback_source: metadataSource === 'spotify_free' ? 'spotify' : metadataSource,
+            spotify_free: metadataSource === 'spotify_free'
         },
         hydrabase: {
             url: document.getElementById('hydrabase-url').value,
@@ -2938,7 +2983,8 @@ async function saveSettings(quiet = false) {
             allow_duplicate_tracks: document.getElementById('allow-duplicate-tracks').checked
         },
         playlist_sync: {
-            create_backup: document.getElementById('create-backup').checked
+            create_backup: document.getElementById('create-backup').checked,
+            mode: document.getElementById('playlist-sync-mode')?.value || 'replace'
         },
         content_filter: {
             allow_explicit: document.getElementById('allow-explicit').checked

webui/static/shared-helpers.js

@@ -110,6 +110,10 @@ async function fetchSourceConfiguredMap() {
             for (const src of SOURCE_ORDER) {
                 if (_ALWAYS_CONFIGURED_SOURCES.has(src)) {
                     map[src] = true;
+                } else if (src === 'spotify') {
+                    // Spotify Free: available without credentials when the
+                    // opt-in no-creds source is on (metadata_available).
+                    map[src] = !!(data[src] && (data[src].configured || data[src].metadata_available));
                 } else {
                     map[src] = !!(data[src] && data[src].configured);
                 }
@@ -1265,8 +1269,10 @@ function playlistModalDownloadSyncFooterHtml(playlistId, options = {}) {
     }
 
     return `${downloadBtns}
-        <select id="sync-mode-${playlistId}" class="playlist-modal-sync-mode" title="Replace overwrites the server playlist; Append only adds new tracks (preserves user-added)">
-            <option value="replace" selected>Replace</option>
+        <select id="sync-mode-${playlistId}" class="playlist-modal-sync-mode" title="Default uses your Settings > Playlist sync mode. Replace overwrites the server playlist; Reconcile edits it in place (keeps custom image/description); Append only adds new tracks.">
+            <option value="" selected>Sync mode: default</option>
+            <option value="replace">Replace</option>
+            <option value="reconcile">Reconcile (keep image/desc)</option>
             <option value="append">Append only</option>
         </select>
         <button id="sync-btn-${playlistId}" class="playlist-modal-btn playlist-modal-btn-primary" onclick="startPlaylistSync('${playlistId}')" ${isSyncing ? 'disabled' : ''}>${isSyncing ? '⏳ Syncing...' : 'Sync Playlist'}</button>`;
@@ -1477,6 +1483,10 @@ async function openDownloadMissingModalForArtistAlbum(virtualPlaylistId, playlis
                             <input type="checkbox" id="force-download-all-${virtualPlaylistId}">
                             <span>Force Download All</span>
                         </label>
+                        <label class="force-download-toggle" title="Skip the AcoustID fingerprint check for this request. Useful for non-English artists whose original-language metadata AcoustID can't match against the romanized request (issue #797).">
+                            <input type="checkbox" id="skip-acoustid-${virtualPlaylistId}">
+                            <span>Skip AcoustID verification</span>
+                        </label>
                         ${contextType === 'playlist' ? `
                         <label class="force-download-toggle">
                             <input type="checkbox" id="playlist-folder-mode-${virtualPlaylistId}">