Add Deezer as configurable free metadata fallback source alongside iTunes

Users can now choose between iTunes/Apple Music and Deezer as their free
metadata source in Settings. Spotify always takes priority when authenticated;
the fallback handles all lookups when it's not.

Core changes:
- DeezerClient: full metadata interface (search, albums, artists, tracks)
  matching iTunesClient's API surface with identical dataclass return types
- SpotifyClient: configurable _fallback property switches between iTunes/Deezer
  based on live config reads (no restart needed)
- MetadataService, web_server, watchlist_scanner, api/search, repair_worker,
  seasonal_discovery, personalized_playlists: all direct iTunesClient imports
  replaced with fallback-aware helpers

Database:
- deezer_artist_id on watchlist_artists and similar_artists tables
- deezer_track_id/album_id/artist_id on discovery_pool and discovery_cache
- Full CRUD for Deezer IDs: add, read, update, backfill, metadata enrichment
- Watchlist duplicate detection by artist name prevents re-adding across sources
- SimilarArtist dataclass and all query/insert methods handle Deezer columns

Bug fixes found during review:
- Similar artist backfill was writing Deezer IDs into iTunes columns
- Discover hero was storing resolved Deezer IDs in wrong column
- Status cache not invalidating on settings save (source name lag)
- Watchlist add allowing duplicates when switching metadata sources

api/search.py

@@ -48,13 +48,14 @@ def register_routes(bp):
                     tracks = [_serialize_track(t) for t in results]
                     return api_success({"tracks": tracks, "source": "spotify"})
 
-            if source in ("itunes", "auto"):
-                from core.itunes_client import iTunesClient
-                itunes = iTunesClient()
-                results = itunes.search_tracks(query, limit=limit)
+            if source in ("itunes", "deezer", "auto"):
+                from core.metadata_service import _create_fallback_client, _get_configured_fallback_source
+                fallback = _create_fallback_client()
+                fallback_source = _get_configured_fallback_source()
+                results = fallback.search_tracks(query, limit=limit)
                 if results:
                     tracks = [_serialize_track(t) for t in results]
-                    return api_success({"tracks": tracks, "source": "itunes"})
+                    return api_success({"tracks": tracks, "source": fallback_source})
 
             return api_success({"tracks": [], "source": source})
         except Exception as e:
@@ -85,12 +86,13 @@ def register_routes(bp):
                         "source": "spotify",
                     })
 
-            from core.itunes_client import iTunesClient
-            itunes = iTunesClient()
-            results = itunes.search_albums(query, limit=limit)
+            from core.metadata_service import _create_fallback_client, _get_configured_fallback_source
+            fallback = _create_fallback_client()
+            fallback_source = _get_configured_fallback_source()
+            results = fallback.search_albums(query, limit=limit)
             return api_success({
                 "albums": [_serialize_album(a) for a in results] if results else [],
-                "source": "itunes",
+                "source": fallback_source,
             })
         except Exception as e:
             return api_error("SEARCH_ERROR", str(e), 500)
@@ -120,12 +122,13 @@ def register_routes(bp):
                         "source": "spotify",
                     })
 
-            from core.itunes_client import iTunesClient
-            itunes = iTunesClient()
-            results = itunes.search_artists(query, limit=limit)
+            from core.metadata_service import _create_fallback_client, _get_configured_fallback_source
+            fallback = _create_fallback_client()
+            fallback_source = _get_configured_fallback_source()
+            results = fallback.search_artists(query, limit=limit)
             return api_success({
                 "artists": [_serialize_artist(a) for a in results] if results else [],
-                "source": "itunes",
+                "source": fallback_source,
             })
         except Exception as e:
             return api_error("SEARCH_ERROR", str(e), 500)

core/deezer_client.py

@@ -4,7 +4,9 @@ import time
 import threading
 from typing import Dict, List, Optional, Any
 from functools import wraps
+from dataclasses import dataclass
 from utils.logging_config import get_logger
+from core.metadata_cache import get_metadata_cache
 
 logger = get_logger("deezer_client")
 
@@ -40,8 +42,160 @@ def rate_limited(func):
     return wrapper
 
 
+# ==================== Dataclasses (match iTunesClient / SpotifyClient format) ====================
+
+@dataclass
+class Track:
+    id: str
+    name: str
+    artists: List[str]
+    album: str
+    duration_ms: int
+    popularity: int
+    preview_url: Optional[str] = None
+    external_urls: Optional[Dict[str, str]] = None
+    image_url: Optional[str] = None
+    release_date: Optional[str] = None
+    track_number: Optional[int] = None
+    disc_number: Optional[int] = None
+
+    @classmethod
+    def from_deezer_track(cls, track_data: Dict[str, Any]) -> 'Track':
+        # Extract album image
+        album_data = track_data.get('album', {})
+        album_image_url = None
+        if isinstance(album_data, dict):
+            album_image_url = album_data.get('cover_xl') or album_data.get('cover_big') or album_data.get('cover_medium')
+
+        # Get artist name
+        artist_data = track_data.get('artist', {})
+        artist_name = artist_data.get('name', 'Unknown Artist') if isinstance(artist_data, dict) else 'Unknown Artist'
+
+        # Get album name
+        album_name = ''
+        if isinstance(album_data, dict):
+            album_name = album_data.get('title', '')
+        elif isinstance(album_data, str):
+            album_name = album_data
+
+        # Build external URLs
+        external_urls = {}
+        if track_data.get('link'):
+            external_urls['deezer'] = track_data['link']
+
+        return cls(
+            id=str(track_data.get('id', '')),
+            name=track_data.get('title', ''),
+            artists=[artist_name],
+            album=album_name,
+            duration_ms=track_data.get('duration', 0) * 1000,  # Deezer returns seconds
+            popularity=track_data.get('rank', 0),
+            preview_url=track_data.get('preview'),
+            external_urls=external_urls if external_urls else None,
+            image_url=album_image_url,
+            release_date=track_data.get('release_date') or (album_data.get('release_date') if isinstance(album_data, dict) else None),
+            track_number=track_data.get('track_position'),
+            disc_number=track_data.get('disk_number', 1),
+        )
+
+
+@dataclass
+class Artist:
+    id: str
+    name: str
+    popularity: int
+    genres: List[str]
+    followers: int
+    image_url: Optional[str] = None
+    external_urls: Optional[Dict[str, str]] = None
+
+    @classmethod
+    def from_deezer_artist(cls, artist_data: Dict[str, Any]) -> 'Artist':
+        image_url = artist_data.get('picture_xl') or artist_data.get('picture_big') or artist_data.get('picture_medium')
+
+        external_urls = {}
+        if artist_data.get('link'):
+            external_urls['deezer'] = artist_data['link']
+
+        return cls(
+            id=str(artist_data.get('id', '')),
+            name=artist_data.get('name', ''),
+            popularity=0,
+            genres=[],
+            followers=artist_data.get('nb_fan', 0),
+            image_url=image_url,
+            external_urls=external_urls if external_urls else None
+        )
+
+
+@dataclass
+class Album:
+    id: str
+    name: str
+    artists: List[str]
+    release_date: str
+    total_tracks: int
+    album_type: str
+    image_url: Optional[str] = None
+    external_urls: Optional[Dict[str, str]] = None
+
+    @classmethod
+    def from_deezer_album(cls, album_data: Dict[str, Any]) -> 'Album':
+        image_url = album_data.get('cover_xl') or album_data.get('cover_big') or album_data.get('cover_medium')
+
+        external_urls = {}
+        if album_data.get('link'):
+            external_urls['deezer'] = album_data['link']
+
+        artist_data = album_data.get('artist', {})
+        artist_name = artist_data.get('name', 'Unknown Artist') if isinstance(artist_data, dict) else 'Unknown Artist'
+
+        # Map Deezer record_type
+        record_type = album_data.get('record_type', 'album')
+        if record_type == 'single':
+            album_type = 'single'
+        elif record_type == 'ep':
+            album_type = 'ep'
+        elif record_type == 'compile':
+            album_type = 'compilation'
+        else:
+            album_type = 'album'
+
+        return cls(
+            id=str(album_data.get('id', '')),
+            name=album_data.get('title', ''),
+            artists=[artist_name],
+            release_date=album_data.get('release_date', ''),
+            total_tracks=album_data.get('nb_tracks', 0),
+            album_type=album_type,
+            image_url=image_url,
+            external_urls=external_urls if external_urls else None
+        )
+
+
+@dataclass
+class Playlist:
+    id: str
+    name: str
+    description: Optional[str]
+    owner: str
+    public: bool
+    collaborative: bool
+    tracks: List[Track]
+    total_tracks: int
+
+
 class DeezerClient:
-    """Client for interacting with the Deezer API"""
+    """
+    Deezer API client for music metadata and playlist access.
+
+    Provides metadata parity with iTunesClient for use as a fallback source.
+    Also provides enrichment methods (search_artist, search_album, search_track)
+    and playlist methods used by deezer_worker.py.
+
+    Free, no authentication required.
+    Rate limit: ~50 calls/5s.
+    """
 
     BASE_URL = "https://api.deezer.com"
 
@@ -53,10 +207,441 @@ class DeezerClient:
         })
         logger.info("Deezer client initialized")
 
+    def is_authenticated(self) -> bool:
+        """Deezer public API requires no authentication — always available"""
+        return True
+
+    def reload_config(self):
+        """Reload configuration (no-op for Deezer since no auth required)"""
+        pass
+
+    def _api_get(self, endpoint: str, params: dict = None, timeout: int = 15) -> Optional[Dict[str, Any]]:
+        """Generic GET request to Deezer API with error handling"""
+        try:
+            url = f"{self.BASE_URL}/{endpoint.lstrip('/')}"
+            response = self.session.get(url, params=params, timeout=timeout)
+
+            if response.status_code != 200:
+                logger.error(f"Deezer API returned status {response.status_code} for {endpoint}")
+                return None
+
+            data = response.json()
+
+            if 'error' in data:
+                error = data['error']
+                error_type = error.get('type', 'Unknown')
+                error_msg = error.get('message', 'Unknown error')
+                if error_type == 'DataException':
+                    logger.debug(f"Deezer data not found: {endpoint}")
+                else:
+                    logger.error(f"Deezer API error ({error_type}): {error_msg}")
+                return None
+
+            return data
+
+        except Exception as e:
+            logger.error(f"Error in Deezer API request ({endpoint}): {e}")
+            return None
+
+    # ==================== Metadata Source Methods (iTunesClient parity) ====================
+    # These methods follow the same interface as iTunesClient so DeezerClient
+    # can serve as a drop-in fallback metadata source in SpotifyClient.
+
+    @rate_limited
+    def search_tracks(self, query: str, limit: int = 20) -> List[Track]:
+        """Search for tracks — returns Track dataclass list (metadata source interface)"""
+        cache = get_metadata_cache()
+        cached_results = cache.get_search_results('deezer', 'track', query, limit)
+        if cached_results is not None:
+            tracks = []
+            for raw in cached_results:
+                try:
+                    tracks.append(Track.from_deezer_track(raw))
+                except Exception:
+                    pass
+            if tracks:
+                return tracks
+
+        data = self._api_get('search/track', {'q': query, 'limit': min(limit, 100)})
+        if not data or 'data' not in data:
+            return []
+
+        tracks = []
+        raw_items = []
+        for track_data in data['data']:
+            track = Track.from_deezer_track(track_data)
+            tracks.append(track)
+            raw_items.append(track_data)
+
+        entries = [(str(td.get('id', '')), td) for td in raw_items if td.get('id')]
+        if entries:
+            cache.store_entities_bulk('deezer', 'track', entries)
+            cache.store_search_results('deezer', 'track', query, limit,
+                                       [str(td.get('id', '')) for td in raw_items if td.get('id')])
+
+        return tracks
+
+    @rate_limited
+    def search_artists(self, query: str, limit: int = 20) -> List[Artist]:
+        """Search for artists — returns Artist dataclass list (metadata source interface)"""
+        cache = get_metadata_cache()
+        cached_results = cache.get_search_results('deezer', 'artist', query, limit)
+        if cached_results is not None:
+            artists = []
+            for raw in cached_results:
+                try:
+                    artists.append(Artist.from_deezer_artist(raw))
+                except Exception:
+                    pass
+            if artists:
+                return artists
+
+        data = self._api_get('search/artist', {'q': query, 'limit': min(limit, 100)})
+        if not data or 'data' not in data:
+            return []
+
+        artists = []
+        raw_items = []
+        for artist_data in data['data']:
+            artist = Artist.from_deezer_artist(artist_data)
+            artists.append(artist)
+            raw_items.append(artist_data)
+
+        entries = [(str(ad.get('id', '')), ad) for ad in raw_items if ad.get('id')]
+        if entries:
+            cache.store_entities_bulk('deezer', 'artist', entries)
+            cache.store_search_results('deezer', 'artist', query, limit,
+                                       [str(ad.get('id', '')) for ad in raw_items if ad.get('id')])
+
+        return artists
+
+    @rate_limited
+    def search_albums(self, query: str, limit: int = 20) -> List[Album]:
+        """Search for albums — returns Album dataclass list (metadata source interface)"""
+        cache = get_metadata_cache()
+        cached_results = cache.get_search_results('deezer', 'album', query, limit)
+        if cached_results is not None:
+            albums = []
+            for raw in cached_results:
+                try:
+                    albums.append(Album.from_deezer_album(raw))
+                except Exception:
+                    pass
+            if albums:
+                return albums
+
+        data = self._api_get('search/album', {'q': query, 'limit': min(limit, 100)})
+        if not data or 'data' not in data:
+            return []
+
+        albums = []
+        raw_items = []
+        for album_data in data['data']:
+            album = Album.from_deezer_album(album_data)
+            albums.append(album)
+            raw_items.append(album_data)
+
+        entries = [(str(ad.get('id', '')), ad) for ad in raw_items if ad.get('id')]
+        if entries:
+            cache.store_entities_bulk('deezer', 'album', entries, skip_if_exists=True)
+            cache.store_search_results('deezer', 'album', query, limit,
+                                       [str(ad.get('id', '')) for ad in raw_items if ad.get('id')])
+
+        return albums[:limit]
+
+    def get_track_details(self, track_id: str) -> Optional[Dict[str, Any]]:
+        """Get detailed track info — returns Spotify-compatible dict (metadata source interface)"""
+        cache = get_metadata_cache()
+        cached = cache.get_entity('deezer', 'track', str(track_id))
+        if cached and cached.get('title'):
+            return self._build_enhanced_track(cached)
+
+        data = self._api_get(f'track/{track_id}')
+        if not data:
+            return None
+
+        cache.store_entity('deezer', 'track', str(track_id), data)
+        return self._build_enhanced_track(data)
+
+    def _build_enhanced_track(self, track_data: Dict[str, Any]) -> Dict[str, Any]:
+        """Build Spotify-compatible enhanced track dict from raw Deezer data"""
+        artist_data = track_data.get('artist', {})
+        album_data = track_data.get('album', {})
+
+        artist_name = artist_data.get('name', 'Unknown Artist') if isinstance(artist_data, dict) else 'Unknown Artist'
+        album_name = album_data.get('title', '') if isinstance(album_data, dict) else str(album_data) if album_data else ''
+        album_id = str(album_data.get('id', '')) if isinstance(album_data, dict) else ''
+
+        return {
+            'id': str(track_data.get('id', '')),
+            'name': track_data.get('title', ''),
+            'track_number': track_data.get('track_position', 0),
+            'disc_number': track_data.get('disk_number', 1),
+            'duration_ms': track_data.get('duration', 0) * 1000,
+            'explicit': track_data.get('explicit_lyrics', False),
+            'artists': [artist_name],
+            'primary_artist': artist_name,
+            'album': {
+                'id': album_id,
+                'name': album_name,
+                'total_tracks': album_data.get('nb_tracks', 0) if isinstance(album_data, dict) else 0,
+                'release_date': track_data.get('release_date', '') or (album_data.get('release_date', '') if isinstance(album_data, dict) else ''),
+                'album_type': 'album',
+                'artists': [artist_name]
+            },
+            'is_album_track': (album_data.get('nb_tracks', 0) if isinstance(album_data, dict) else 0) > 1,
+            'raw_data': track_data
+        }
+
+    def get_track_features(self, track_id: str) -> Optional[Dict[str, Any]]:
+        """Deezer does not provide audio features like Spotify"""
+        return None
+
+    def get_album_metadata(self, album_id: str, include_tracks: bool = True) -> Optional[Dict[str, Any]]:
+        """Get album info — returns Spotify-compatible dict (metadata source interface).
+
+        Matches iTunesClient.get_album() interface. The enrichment method below
+        is get_album_raw() (used by deezer_worker.py)."""
+        cache = get_metadata_cache()
+        cached = cache.get_entity('deezer', 'album', str(album_id))
+        if cached and cached.get('title'):
+            return self._build_album_result(cached, album_id, include_tracks)
+
+        data = self._api_get(f'album/{album_id}')
+        if not data:
+            return None
+
+        cache.store_entity('deezer', 'album', str(album_id), data)
+        return self._build_album_result(data, album_id, include_tracks)
+
+    def _build_album_result(self, album_data: Dict[str, Any], album_id: str, include_tracks: bool = True) -> Dict[str, Any]:
+        """Build Spotify-compatible album result from Deezer data"""
+        images = []
+        for size_key, height in [('cover_xl', 1000), ('cover_big', 500), ('cover_medium', 250), ('cover_small', 56)]:
+            if album_data.get(size_key):
+                images.append({'url': album_data[size_key], 'height': height, 'width': height})
+
+        artist_data = album_data.get('artist', {})
+        artist_name = artist_data.get('name', 'Unknown Artist') if isinstance(artist_data, dict) else 'Unknown Artist'
+        artist_id = str(artist_data.get('id', '')) if isinstance(artist_data, dict) else ''
+
+        record_type = album_data.get('record_type', 'album')
+        if record_type == 'single':
+            album_type = 'single'
+        elif record_type == 'ep':
+            album_type = 'ep'
+        elif record_type == 'compile':
+            album_type = 'compilation'
+        else:
+            album_type = 'album'
+
+        album_result = {
+            'id': str(album_data.get('id', album_id)),
+            'name': album_data.get('title', ''),
+            'images': images,
+            'artists': [{'name': artist_name, 'id': artist_id}],
+            'release_date': album_data.get('release_date', ''),
+            'total_tracks': album_data.get('nb_tracks', 0),
+            'album_type': album_type,
+            'external_urls': {'deezer': album_data.get('link', '')},
+            'uri': f"deezer:album:{album_data.get('id', '')}",
+            '_source': 'deezer',
+            '_raw_data': album_data
+        }
+
+        if include_tracks:
+            tracks_data = self.get_album_tracks(album_id)
+            if tracks_data and 'items' in tracks_data:
+                album_result['tracks'] = tracks_data
+            else:
+                album_result['tracks'] = {'items': [], 'total': 0}
+
+        return album_result
+
+    def get_album_tracks(self, album_id: str) -> Optional[Dict[str, Any]]:
+        """Get album tracks — returns Spotify-compatible format (metadata source interface)"""
+        cache = get_metadata_cache()
+        cached = cache.get_entity('deezer', 'album', f"{album_id}_tracks")
+        if cached:
+            return cached
+
+        data = self._api_get(f'album/{album_id}/tracks', {'limit': 500})
+        if not data or 'data' not in data:
+            album_data = self._api_get(f'album/{album_id}')
+            if album_data and 'tracks' in album_data and 'data' in album_data['tracks']:
+                data = album_data['tracks']
+            else:
+                return None
+
+        # Get album-level info for images and name
+        album_info = self._api_get(f'album/{album_id}')
+        album_images = []
+        album_name = ''
+        if album_info:
+            album_name = album_info.get('title', '')
+            for size_key, height in [('cover_xl', 1000), ('cover_big', 500), ('cover_medium', 250)]:
+                if album_info.get(size_key):
+                    album_images.append({'url': album_info[size_key], 'height': height, 'width': height})
+
+        tracks = []
+        for item in data['data']:
+            artist_data = item.get('artist', {})
+            artist_name = artist_data.get('name', 'Unknown Artist') if isinstance(artist_data, dict) else 'Unknown Artist'
+
+            normalized_track = {
+                'id': str(item.get('id', '')),
+                'name': item.get('title', ''),
+                'artists': [{'name': artist_name}],
+                'album': {
+                    'id': str(album_id),
+                    'name': album_name,
+                    'images': album_images,
+                    'release_date': album_info.get('release_date', '') if album_info else ''
+                },
+                'duration_ms': item.get('duration', 0) * 1000,
+                'track_number': item.get('track_position', 0),
+                'disc_number': item.get('disk_number', 1),
+                'explicit': item.get('explicit_lyrics', False),
+                'preview_url': item.get('preview'),
+                'uri': f"deezer:track:{item.get('id', '')}",
+                'external_urls': {'deezer': item.get('link', '')},
+                '_source': 'deezer'
+            }
+            tracks.append(normalized_track)
+
+        tracks.sort(key=lambda t: (t.get('disc_number', 1), t.get('track_number', 0)))
+
+        logger.info(f"Retrieved {len(tracks)} tracks for album {album_id}")
+
+        result = {
+            'items': tracks,
+            'total': len(tracks),
+            'limit': len(tracks),
+            'next': None
+        }
+
+        cache.store_entity('deezer', 'album', f"{album_id}_tracks", result)
+
+        # Cache individual tracks
+        for item in data['data']:
+            if item.get('id'):
+                cache.store_entity('deezer', 'track', str(item['id']), item)
+
+        return result
+
+    def get_artist_info(self, artist_id: str) -> Optional[Dict[str, Any]]:
+        """Get full artist details — returns Spotify-compatible dict (metadata source interface).
+
+        Matches iTunesClient.get_artist() interface."""
+        cache = get_metadata_cache()
+        cached = cache.get_entity('deezer', 'artist', str(artist_id))
+        if cached and cached.get('name'):
+            return self._build_artist_result(cached)
+
+        data = self._api_get(f'artist/{artist_id}')
+        if not data:
+            return None
+
+        cache.store_entity('deezer', 'artist', str(artist_id), data)
+        return self._build_artist_result(data)
+
+    def _build_artist_result(self, artist_data: Dict[str, Any]) -> Dict[str, Any]:
+        """Build Spotify-compatible artist result from Deezer data"""
+        images = []
+        for size_key, height in [('picture_xl', 1000), ('picture_big', 500), ('picture_medium', 250), ('picture_small', 56)]:
+            if artist_data.get(size_key):
+                images.append({'url': artist_data[size_key], 'height': height, 'width': height})
+
+        return {
+            'id': str(artist_data.get('id', '')),
+            'name': artist_data.get('name', ''),
+            'images': images,
+            'genres': [],
+            'popularity': 0,
+            'followers': {'total': artist_data.get('nb_fan', 0)},
+            'external_urls': {'deezer': artist_data.get('link', '')},
+            'uri': f"deezer:artist:{artist_data.get('id', '')}",
+            '_source': 'deezer',
+            '_raw_data': artist_data
+        }
+
+    def get_artist_albums_list(self, artist_id: str, album_type: str = 'album,single', limit: int = 50) -> List[Album]:
+        """Get albums by artist ID — returns Album dataclass list (metadata source interface).
+
+        Matches iTunesClient.get_artist_albums() interface."""
+        data = self._api_get(f'artist/{artist_id}/albums', {'limit': min(limit, 100)})
+        if not data or 'data' not in data:
+            return []
+
+        albums = []
+        requested_types = [t.strip() for t in album_type.split(',')]
+
+        for album_data in data['data']:
+            album = Album.from_deezer_album(album_data)
+
+            if album_type != 'album,single':
+                if album.album_type not in requested_types:
+                    if not (album.album_type == 'ep' and 'single' in requested_types):
+                        continue
+
+            albums.append(album)
+
+        cache = get_metadata_cache()
+        entries = [(str(ad.get('id', '')), ad) for ad in data['data'] if ad.get('id')]
+        if entries:
+            cache.store_entities_bulk('deezer', 'album', entries, skip_if_exists=True)
+
+        logger.info(f"Retrieved {len(albums)} albums for artist {artist_id}")
+        return albums[:limit]
+
+    # ==================== Interface Aliases (match iTunesClient method names) ====================
+    # These allow SpotifyClient to call self._fallback.get_album() etc. without
+    # conditional dispatch — same method names as iTunesClient.
+    get_album = get_album_metadata
+    get_artist = get_artist_info
+    get_artist_albums = get_artist_albums_list
+
+    def _get_artist_image_from_albums(self, artist_id: str) -> Optional[str]:
+        """Compatibility with iTunesClient — Deezer artists have direct image URLs."""
+        artist_data = self._api_get(f'artist/{artist_id}')
+        if artist_data:
+            return artist_data.get('picture_xl') or artist_data.get('picture_big') or artist_data.get('picture_medium')
+        return None
+
+    # ==================== Stub Methods (match iTunesClient interface) ====================
+
+    def get_user_playlists(self) -> List[Playlist]:
+        """Not supported — Deezer playlists require auth"""
+        return []
+
+    def get_user_playlists_metadata_only(self) -> List[Playlist]:
+        """Not supported"""
+        return []
+
+    def get_saved_tracks_count(self) -> int:
+        """Not supported"""
+        return 0
+
+    def get_saved_tracks(self) -> List[Track]:
+        """Not supported"""
+        return []
+
+    def get_playlist_by_id(self, playlist_id: str) -> Optional[Playlist]:
+        """Not supported"""
+        return None
+
+    def get_user_info(self) -> Optional[Dict[str, Any]]:
+        """Not supported — requires auth"""
+        return None
+
+    # ==================== Existing Enrichment Methods ====================
+    # These methods are used by deezer_worker.py and web_server.py enrichment endpoints.
+    # They have different signatures from the metadata-source methods above.
+
     @rate_limited
     def search_artist(self, artist_name: str) -> Optional[Dict[str, Any]]:
         """
-        Search for an artist by name.
+        Search for an artist by name (enrichment interface).
 
         Args:
             artist_name: Name of the artist to search for
@@ -92,7 +677,7 @@ class DeezerClient:
     @rate_limited
     def search_album(self, artist_name: str, album_title: str) -> Optional[Dict[str, Any]]:
         """
-        Search for an album by artist name and album title.
+        Search for an album by artist name and album title (enrichment interface).
 
         Args:
             artist_name: Name of the artist
@@ -130,7 +715,7 @@ class DeezerClient:
     @rate_limited
     def search_track(self, artist_name: str, track_title: str) -> Optional[Dict[str, Any]]:
         """
-        Search for a track by artist name and track title.
+        Search for a track by artist name and track title (enrichment interface).
 
         Args:
             artist_name: Name of the artist
@@ -166,9 +751,10 @@ class DeezerClient:
             return None
 
     @rate_limited
-    def get_album(self, album_id: int) -> Optional[Dict[str, Any]]:
+    def get_album_raw(self, album_id: int) -> Optional[Dict[str, Any]]:
         """
-        Get full album details by ID.
+        Get full album details by ID — raw Deezer format (enrichment interface).
+        Used by deezer_worker.py for label/genre/explicit enrichment.
 
         Args:
             album_id: Deezer album ID
@@ -196,9 +782,10 @@ class DeezerClient:
             return None
 
     @rate_limited
-    def get_track(self, track_id: int) -> Optional[Dict[str, Any]]:
+    def get_track_raw(self, track_id: int) -> Optional[Dict[str, Any]]:
         """
-        Get full track details by ID (includes BPM).
+        Get full track details by ID — raw Deezer format (enrichment interface, includes BPM).
+        Used by deezer_worker.py for BPM enrichment.
 
         Args:
             track_id: Deezer track ID

core/deezer_worker.py

@@ -363,7 +363,7 @@ class DeezerWorker:
                 full_album = None
                 if deezer_album_id:
                     try:
-                        full_album = self.client.get_album(deezer_album_id)
+                        full_album = self.client.get_album_raw(deezer_album_id)
                     except Exception as e:
                         logger.warning(f"Failed to fetch full album details for '{album_name}' (Deezer ID: {deezer_album_id}): {e}")
 
@@ -403,7 +403,7 @@ class DeezerWorker:
                 full_track = None
                 if deezer_track_id:
                     try:
-                        full_track = self.client.get_track(deezer_track_id)
+                        full_track = self.client.get_track_raw(deezer_track_id)
                     except Exception as e:
                         logger.warning(f"Failed to fetch full track details for '{track_name}' (Deezer ID: {deezer_track_id}): {e}")
 

core/metadata_cache.py

@@ -465,9 +465,9 @@ class MetadataCache:
                 cursor = conn.cursor()
 
                 stats = {
-                    'artists': {'spotify': 0, 'itunes': 0},
-                    'albums': {'spotify': 0, 'itunes': 0},
-                    'tracks': {'spotify': 0, 'itunes': 0},
+                    'artists': {'spotify': 0, 'itunes': 0, 'deezer': 0},
+                    'albums': {'spotify': 0, 'itunes': 0, 'deezer': 0},
+                    'tracks': {'spotify': 0, 'itunes': 0, 'deezer': 0},
                     'searches': 0,
                     'total_entries': 0,
                     'total_hits': 0,
@@ -509,9 +509,9 @@ class MetadataCache:
         except Exception as e:
             logger.error(f"Cache stats error: {e}")
             return {
-                'artists': {'spotify': 0, 'itunes': 0},
-                'albums': {'spotify': 0, 'itunes': 0},
-                'tracks': {'spotify': 0, 'itunes': 0},
+                'artists': {'spotify': 0, 'itunes': 0, 'deezer': 0},
+                'albums': {'spotify': 0, 'itunes': 0, 'deezer': 0},
+                'tracks': {'spotify': 0, 'itunes': 0, 'deezer': 0},
                 'searches': 0, 'total_entries': 0, 'total_hits': 0,
                 'oldest': None, 'newest': None,
             }
@@ -610,6 +610,8 @@ class MetadataCache:
             return self._extract_spotify_fields(entity_type, raw_data)
         elif source == 'itunes':
             return self._extract_itunes_fields(entity_type, raw_data)
+        elif source == 'deezer':
+            return self._extract_deezer_fields(entity_type, raw_data)
         return {'name': str(raw_data.get('name', raw_data.get('trackName', '')))}
 
     def _extract_spotify_fields(self, entity_type: str, data: dict) -> dict:
@@ -664,6 +666,60 @@ class MetadataCache:
 
         return fields
 
+    def _extract_deezer_fields(self, entity_type: str, data: dict) -> dict:
+        """Extract fields from Deezer API response."""
+        fields = {}
+
+        if entity_type == 'artist':
+            fields['name'] = data.get('name', '')
+            fields['genres'] = '[]'
+            fields['popularity'] = 0
+            fields['followers'] = data.get('nb_fan', 0)
+            fields['image_url'] = data.get('picture_xl') or data.get('picture_big') or data.get('picture_medium')
+            urls = {}
+            if data.get('link'):
+                urls['deezer'] = data['link']
+            fields['external_urls'] = json.dumps(urls)
+
+        elif entity_type == 'album':
+            fields['name'] = data.get('title', '')
+            artist = data.get('artist', {})
+            fields['artist_name'] = artist.get('name', '') if isinstance(artist, dict) else ''
+            fields['artist_id'] = str(artist.get('id', '')) if isinstance(artist, dict) else ''
+            fields['release_date'] = data.get('release_date', '')
+            fields['total_tracks'] = data.get('nb_tracks', 0)
+            record_type = data.get('record_type', 'album')
+            fields['album_type'] = record_type if record_type in ('single', 'ep', 'album') else 'album'
+            fields['label'] = data.get('label', '')
+            fields['image_url'] = data.get('cover_xl') or data.get('cover_big') or data.get('cover_medium')
+            urls = {}
+            if data.get('link'):
+                urls['deezer'] = data['link']
+            fields['external_urls'] = json.dumps(urls)
+
+        elif entity_type == 'track':
+            fields['name'] = data.get('title', '')
+            artist = data.get('artist', {})
+            fields['artist_name'] = artist.get('name', '') if isinstance(artist, dict) else ''
+            fields['artist_id'] = str(artist.get('id', '')) if isinstance(artist, dict) else ''
+            album = data.get('album', {})
+            fields['album_name'] = album.get('title', '') if isinstance(album, dict) else ''
+            fields['album_id'] = str(album.get('id', '')) if isinstance(album, dict) else ''
+            fields['image_url'] = (album.get('cover_xl') or album.get('cover_big') or album.get('cover_medium')) if isinstance(album, dict) else None
+            fields['duration_ms'] = data.get('duration', 0) * 1000
+            fields['track_number'] = data.get('track_position')
+            fields['disc_number'] = data.get('disk_number', 1)
+            fields['explicit'] = 1 if data.get('explicit_lyrics') else 0
+            fields['popularity'] = data.get('rank', 0)
+            fields['isrc'] = data.get('isrc')
+            fields['preview_url'] = data.get('preview')
+            urls = {}
+            if data.get('link'):
+                urls['deezer'] = data['link']
+            fields['external_urls'] = json.dumps(urls)
+
+        return fields
+
     def _extract_itunes_fields(self, entity_type: str, data: dict) -> dict:
         """Extract fields from iTunes API response."""
         fields = {}

core/metadata_service.py

@@ -1,7 +1,8 @@
 """
-Metadata Service - Hot-swappable Spotify/iTunes provider
+Metadata Service - Hot-swappable Spotify/iTunes/Deezer provider
 
-Automatically uses Spotify when authenticated, falls back to iTunes when not.
+Automatically uses Spotify when authenticated, falls back to the configured
+fallback source (iTunes or Deezer) when not.
 Provides unified interface for all metadata operations.
 """
 
@@ -15,63 +16,83 @@ logger = get_logger("metadata_service")
 MetadataProvider = Literal["spotify", "itunes", "auto"]
 
 
+def _get_configured_fallback_source():
+    """Get the configured metadata fallback source ('itunes' or 'deezer')."""
+    try:
+        from config.settings import config_manager
+        return config_manager.get('metadata.fallback_source', 'itunes') or 'itunes'
+    except Exception:
+        return 'itunes'
+
+
+def _create_fallback_client():
+    """Create the configured fallback metadata client."""
+    source = _get_configured_fallback_source()
+    if source == 'deezer':
+        from core.deezer_client import DeezerClient
+        return DeezerClient()
+    return iTunesClient()
+
+
 class MetadataService:
     """
-    Unified metadata service that seamlessly switches between Spotify and iTunes.
-    
+    Unified metadata service that seamlessly switches between Spotify and
+    the configured fallback source (iTunes or Deezer).
+
     Usage:
         service = MetadataService()
         tracks = service.search_tracks("Radiohead OK Computer")
-        # Uses Spotify if authenticated, otherwise iTunes
+        # Uses Spotify if authenticated, otherwise configured fallback
     """
-    
+
     def __init__(self, preferred_provider: MetadataProvider = "auto"):
         """
         Initialize metadata service.
-        
+
         Args:
             preferred_provider: "spotify", "itunes", or "auto" (default)
-                - "auto": Use Spotify if authenticated, else iTunes
+                - "auto": Use Spotify if authenticated, else configured fallback
                 - "spotify": Always use Spotify (may fail if not authenticated)
-                - "itunes": Always use iTunes
+                - "itunes": Always use configured fallback source
         """
         self.preferred_provider = preferred_provider
         self.spotify = SpotifyClient()
-        self.itunes = iTunesClient()
-        
+        self._fallback_source = _get_configured_fallback_source()
+        self.itunes = _create_fallback_client()  # May be iTunesClient or DeezerClient
+
         self._log_initialization()
-    
+
     def _log_initialization(self):
         """Log initialization status"""
         spotify_status = "✅ Authenticated" if self.spotify.is_spotify_authenticated() else "❌ Not authenticated"
-        itunes_status = "✅ Available" if self.itunes.is_authenticated() else "❌ Not available"
-        
-        logger.info(f"MetadataService initialized - Spotify: {spotify_status}, iTunes: {itunes_status}")
+        fallback_status = "✅ Available" if self.itunes.is_authenticated() else "❌ Not available"
+
+        logger.info(f"MetadataService initialized - Spotify: {spotify_status}, {self._fallback_source.capitalize()}: {fallback_status}")
         logger.info(f"Preferred provider: {self.preferred_provider}")
-    
+
     def get_active_provider(self) -> str:
         """
         Get the currently active metadata provider.
 
         Returns:
-            "spotify" or "itunes"
+            "spotify" or the configured fallback source name
         """
         if self.preferred_provider == "spotify":
             return "spotify"
         elif self.preferred_provider == "itunes":
-            return "itunes"
+            return self._fallback_source
         else:  # auto
             # Use is_spotify_authenticated() to check actual Spotify auth status
-            # (is_authenticated() always returns True due to iTunes fallback)
-            return "spotify" if self.spotify.is_spotify_authenticated() else "itunes"
-    
+            # (is_authenticated() always returns True due to fallback)
+            return "spotify" if self.spotify.is_spotify_authenticated() else self._fallback_source
+
     def _get_client(self):
         """Get the appropriate client based on provider selection"""
         provider = self.get_active_provider()
 
         if provider == "spotify":
             if not self.spotify.is_spotify_authenticated():
-                logger.warning("Spotify requested but not authenticated, falling back to iTunes")
+                logger.warning(f"Spotify requested but not authenticated, falling back to {self._fallback_source}")
                 return self.itunes
             return self.spotify
         else:
@@ -200,6 +221,7 @@ class MetadataService:
             "active_provider": self.get_active_provider(),
             "spotify_authenticated": self.spotify.is_spotify_authenticated(),
             "itunes_available": self.itunes.is_authenticated(),
+            "fallback_source": self._fallback_source,
             "preferred_provider": self.preferred_provider,
             "can_access_user_data": self.spotify.is_spotify_authenticated(),
         }
@@ -208,7 +230,13 @@ class MetadataService:
         """Reload configuration for both clients"""
         logger.info("Reloading metadata service configuration")
         self.spotify.reload_config()
-        self.itunes.reload_config()
+        # Re-create fallback client in case the setting changed
+        new_source = _get_configured_fallback_source()
+        if new_source != self._fallback_source:
+            self._fallback_source = new_source
+            self.itunes = _create_fallback_client()
+        elif hasattr(self.itunes, 'reload_config'):
+            self.itunes.reload_config()
         self._log_initialization()
 
 

core/personalized_playlists.py

@@ -951,8 +951,8 @@ class PersonalizedPlaylistsService:
                         logger.warning(f"Error getting albums for {artist.get('name', artist['id'])}: {e}")
                         continue
             else:
-                from core.itunes_client import iTunesClient
-                itunes = iTunesClient()
+                from core.metadata_service import _create_fallback_client
+                itunes = _create_fallback_client()
                 for artist in artists_for_albums:
                     try:
                         albums = itunes.get_artist_albums(artist['id'], limit=10)
@@ -1007,8 +1007,8 @@ class PersonalizedPlaylistsService:
                         logger.warning(f"Error getting tracks from album: {e}")
                         continue
             else:
-                from core.itunes_client import iTunesClient
-                itunes = iTunesClient()
+                from core.metadata_service import _create_fallback_client
+                itunes = _create_fallback_client()
                 for album in selected_albums:
                     try:
                         album_data = itunes.get_album(album.id, include_tracks=True)

core/repair_worker.py

@@ -146,10 +146,10 @@ class RepairWorker:
     def itunes_client(self):
         if self._itunes_client is None:
             try:
-                from core.itunes_client import iTunesClient
-                self._itunes_client = iTunesClient()
+                from core.metadata_service import _create_fallback_client
+                self._itunes_client = _create_fallback_client()
             except Exception as e:
-                logger.error("Failed to initialize iTunesClient: %s", e)
+                logger.error("Failed to initialize fallback metadata client: %s", e)
         return self._itunes_client
 
     @property

core/seasonal_discovery.py

@@ -448,6 +448,10 @@ class SeasonalDiscoveryService:
             # IMPROVED: Sample 20 random watchlist artists (up from 10) for more variety
             sampled_artists = random.sample(watchlist_artists, min(20, len(watchlist_artists)))
 
+            from core.metadata_service import _create_fallback_client, _get_configured_fallback_source
+            fallback_client = _create_fallback_client()
+            fallback_source = _get_configured_fallback_source()
+
             for artist in sampled_artists:
                 try:
                     albums = []
@@ -457,14 +461,14 @@ class SeasonalDiscoveryService:
                             album_type='album,single,ep',
                             limit=50
                         ) or []
-                    elif hasattr(artist, 'itunes_artist_id') and artist.itunes_artist_id:
-                        from core.itunes_client import iTunesClient
-                        itunes_client = iTunesClient()
-                        albums = itunes_client.get_artist_albums(
-                            artist.itunes_artist_id,
-                            album_type='album,single,ep',
-                            limit=50
-                        ) or []
+                    elif not use_spotify:
+                        artist_id = getattr(artist, 'deezer_artist_id', None) if fallback_source == 'deezer' else getattr(artist, 'itunes_artist_id', None)
+                        if artist_id:
+                            albums = fallback_client.get_artist_albums(
+                                artist_id,
+                                album_type='album,single,ep',
+                                limit=50
+                            ) or []
 
                     # Filter albums by seasonal keywords in title
                     for album in albums:
@@ -547,13 +551,13 @@ class SeasonalDiscoveryService:
                         logger.debug(f"Error searching Spotify for '{keyword}': {e}")
                         continue
             else:
-                # iTunes fallback
-                from core.itunes_client import iTunesClient
-                itunes_client = iTunesClient()
+                # Fallback metadata source (iTunes or Deezer)
+                from core.metadata_service import _create_fallback_client
+                fallback_client = _create_fallback_client()
 
                 for keyword in search_keywords:
                     try:
-                        search_results = itunes_client.search_albums(keyword, limit=20)
+                        search_results = fallback_client.search_albums(keyword, limit=20)
 
                         for album in search_results:
                             if album.id in seen_album_ids:
@@ -765,6 +769,9 @@ class SeasonalDiscoveryService:
             seasonal_albums = self.get_seasonal_albums(season_key, limit=50, source=source)
 
             use_spotify = self.spotify_client and self.spotify_client.is_authenticated()
+            if not use_spotify:
+                from core.metadata_service import _create_fallback_client
+                fallback_client = _create_fallback_client()
 
             for album in seasonal_albums:
                 try:
@@ -774,10 +781,7 @@ class SeasonalDiscoveryService:
                     if use_spotify:
                         album_data = self.spotify_client.get_album(album_id)
                     else:
-                        # iTunes fallback
-                        from core.itunes_client import iTunesClient
-                        itunes_client = iTunesClient()
-                        album_data = itunes_client.get_album(album_id)
+                        album_data = fallback_client.get_album(album_id)
 
                     if not album_data or 'tracks' not in album_data:
                         continue

core/spotify_client.py

@@ -407,6 +407,7 @@ class SpotifyClient:
         self.sp: Optional[spotipy.Spotify] = None
         self.user_id: Optional[str] = None
         self._itunes_client = None  # Lazy-loaded iTunes fallback
+        self._deezer_client = None  # Lazy-loaded Deezer fallback
         self._auth_cache_lock = threading.Lock()
         self._auth_cached_result: Optional[bool] = None
         self._auth_cache_time: float = 0
@@ -414,27 +415,51 @@ class SpotifyClient:
         self._setup_client()
 
     def _is_spotify_id(self, id_str: str) -> bool:
-        """Check if an ID is a Spotify ID (alphanumeric) vs iTunes ID (numeric only)"""
+        """Check if an ID is a Spotify ID (alphanumeric) vs a fallback source ID (numeric only)"""
         if not id_str:
             return False
-        # Spotify IDs contain letters and numbers, iTunes IDs are purely numeric
+        # Spotify IDs contain letters and numbers; iTunes/Deezer IDs are purely numeric
         return not id_str.isdigit()
 
     def _is_itunes_id(self, id_str: str) -> bool:
-        """Check if an ID is an iTunes ID (numeric only)"""
+        """Check if an ID is numeric (iTunes or Deezer format, not Spotify)"""
         if not id_str:
             return False
         return id_str.isdigit()
 
     @property
     def _itunes(self):
-        """Lazy-load iTunes client for fallback when Spotify not authenticated"""
+        """Lazy-load iTunes client"""
         if self._itunes_client is None:
             from core.itunes_client import iTunesClient
             self._itunes_client = iTunesClient()
             logger.info("iTunes fallback client initialized")
         return self._itunes_client
 
+    @property
+    def _deezer(self):
+        """Lazy-load Deezer client for metadata fallback"""
+        if self._deezer_client is None:
+            from core.deezer_client import DeezerClient
+            self._deezer_client = DeezerClient()
+            logger.info("Deezer fallback client initialized")
+        return self._deezer_client
+
+    @property
+    def _fallback_source(self) -> str:
+        """Get configured metadata fallback source ('itunes' or 'deezer')"""
+        try:
+            return config_manager.get('metadata.fallback_source', 'itunes') or 'itunes'
+        except Exception:
+            return 'itunes'
+
+    @property
+    def _fallback(self):
+        """Get the active fallback metadata client based on settings"""
+        if self._fallback_source == 'deezer':
+            return self._deezer
+        return self._itunes
+
     def reload_config(self):
         """Reload configuration and re-initialize client"""
         self._invalidate_auth_cache()
@@ -471,14 +496,14 @@ class SpotifyClient:
     def is_authenticated(self) -> bool:
         """
         Check if client can service metadata requests.
-        Returns True if Spotify is authenticated OR iTunes fallback is available.
+        Returns True if Spotify is authenticated OR fallback (iTunes/Deezer) is available.
         For Spotify-specific auth check, use is_spotify_authenticated().
         """
         # If Spotify is authenticated, we're good
         if self.is_spotify_authenticated():
             return True
 
-        # iTunes fallback is always available
+        # Fallback (iTunes or Deezer) is always available — no auth required
         return True
 
     def _invalidate_auth_cache(self):
@@ -920,24 +945,23 @@ class SpotifyClient:
     
     @rate_limited
     def search_tracks(self, query: str, limit: int = 10) -> List[Track]:
-        """Search for tracks - falls back to iTunes if Spotify not authenticated"""
+        """Search for tracks - falls back to configured metadata source if Spotify not authenticated"""
         cache = get_metadata_cache()
         use_spotify = self.is_spotify_authenticated()
-        source = 'spotify' if use_spotify else 'itunes'
-
-        # Check search cache
-        cached_results = cache.get_search_results(source, 'track', query, min(limit, 10))
-        if cached_results is not None:
-            tracks = []
-            for raw in cached_results:
-                try:
-                    tracks.append(Track.from_spotify_track(raw) if source == 'spotify' else Track.from_itunes_track(raw))
-                except Exception:
-                    pass
-            if tracks:
-                return tracks
 
         if use_spotify:
+            # Check Spotify cache
+            cached_results = cache.get_search_results('spotify', 'track', query, min(limit, 10))
+            if cached_results is not None:
+                tracks = []
+                for raw in cached_results:
+                    try:
+                        tracks.append(Track.from_spotify_track(raw))
+                    except Exception:
+                        pass
+                if tracks:
+                    return tracks
+
             try:
                 results = self.sp.search(q=query, type='track', limit=min(limit, 10))
                 tracks = []
@@ -958,32 +982,32 @@ class SpotifyClient:
 
             except Exception as e:
                 logger.error(f"Error searching tracks via Spotify: {e}")
-                # Fall through to iTunes fallback
+                # Fall through to fallback
 
-        # iTunes fallback
-        logger.debug(f"Using iTunes fallback for track search: {query}")
-        return self._itunes.search_tracks(query, limit)
+        # Fallback (iTunes or Deezer — configured in settings)
+        logger.debug(f"Using {self._fallback_source} fallback for track search: {query}")
+        return self._fallback.search_tracks(query, limit)
 
     @rate_limited
     def search_artists(self, query: str, limit: int = 10) -> List[Artist]:
-        """Search for artists - falls back to iTunes if Spotify not authenticated"""
+        """Search for artists - falls back to configured metadata source if Spotify not authenticated"""
         cache = get_metadata_cache()
         use_spotify = self.is_spotify_authenticated()
-        source = 'spotify' if use_spotify else 'itunes'
 
-        # Check search cache
-        cached_results = cache.get_search_results(source, 'artist', query, min(limit, 10))
-        if cached_results is not None:
-            artists = []
-            for raw in cached_results:
-                try:
-                    artists.append(Artist.from_spotify_artist(raw) if source == 'spotify' else Artist.from_itunes_artist(raw))
-                except Exception:
-                    pass
-            if artists:
-                query_lower = query.lower().strip()
-                artists.sort(key=lambda a: (0 if a.name.lower().strip() == query_lower else 1))
-                return artists
+        if use_spotify:
+            # Check Spotify cache
+            cached_results = cache.get_search_results('spotify', 'artist', query, min(limit, 10))
+            if cached_results is not None:
+                artists = []
+                for raw in cached_results:
+                    try:
+                        artists.append(Artist.from_spotify_artist(raw))
+                    except Exception:
+                        pass
+                if artists:
+                    query_lower = query.lower().strip()
+                    artists.sort(key=lambda a: (0 if a.name.lower().strip() == query_lower else 1))
+                    return artists
 
         if use_spotify:
             try:
@@ -1013,31 +1037,31 @@ class SpotifyClient:
                 logger.error(f"Error searching artists via Spotify: {e}")
                 # Fall through to iTunes fallback
 
-        # iTunes fallback
-        logger.debug(f"Using iTunes fallback for artist search: {query}")
-        artists = self._itunes.search_artists(query, limit)
+        # Fallback (iTunes or Deezer)
+        logger.debug(f"Using {self._fallback_source} fallback for artist search: {query}")
+        artists = self._fallback.search_artists(query, limit)
         query_lower = query.lower().strip()
         artists.sort(key=lambda a: (0 if a.name.lower().strip() == query_lower else 1))
         return artists
 
     @rate_limited
     def search_albums(self, query: str, limit: int = 10) -> List[Album]:
-        """Search for albums - falls back to iTunes if Spotify not authenticated"""
+        """Search for albums - falls back to configured metadata source if Spotify not authenticated"""
         cache = get_metadata_cache()
         use_spotify = self.is_spotify_authenticated()
-        source = 'spotify' if use_spotify else 'itunes'
 
-        # Check search cache
-        cached_results = cache.get_search_results(source, 'album', query, min(limit, 10))
-        if cached_results is not None:
-            albums = []
-            for raw in cached_results:
-                try:
-                    albums.append(Album.from_spotify_album(raw) if source == 'spotify' else Album.from_itunes_album(raw))
-                except Exception:
-                    pass
-            if albums:
-                return albums
+        if use_spotify:
+            # Check Spotify cache
+            cached_results = cache.get_search_results('spotify', 'album', query, min(limit, 10))
+            if cached_results is not None:
+                albums = []
+                for raw in cached_results:
+                    try:
+                        albums.append(Album.from_spotify_album(raw))
+                    except Exception:
+                        pass
+                if albums:
+                    return albums
 
         if use_spotify:
             try:
@@ -1062,16 +1086,17 @@ class SpotifyClient:
                 logger.error(f"Error searching albums via Spotify: {e}")
                 # Fall through to iTunes fallback
 
-        # iTunes fallback
-        logger.debug(f"Using iTunes fallback for album search: {query}")
-        return self._itunes.search_albums(query, limit)
+        # Fallback (iTunes or Deezer)
+        logger.debug(f"Using {self._fallback_source} fallback for album search: {query}")
+        return self._fallback.search_albums(query, limit)
     
     @rate_limited
     def get_track_details(self, track_id: str) -> Optional[Dict[str, Any]]:
-        """Get detailed track information - falls back to iTunes if Spotify not authenticated"""
+        """Get detailed track information - falls back to configured metadata source"""
         # Check cache — we store raw track_data, reconstruct enhanced on hit
         cache = get_metadata_cache()
-        source = 'itunes' if self._is_itunes_id(track_id) else 'spotify'
+        fallback_src = self._fallback_source
+        source = fallback_src if self._is_itunes_id(track_id) else 'spotify'
         cached = cache.get_entity(source, 'track', track_id)
         if cached:
             if source == 'spotify':
@@ -1081,8 +1106,8 @@ class SpotifyClient:
                 # Simplified track cached by get_album_tracks — treat as cache miss
                 logger.debug(f"Cache hit for track {track_id} lacks album data, fetching full data")
             else:
-                # iTunes cache hit — delegate to iTunesClient which reconstructs enhanced format
-                return self._itunes.get_track_details(track_id)
+                # Fallback cache hit — delegate to fallback client which reconstructs enhanced format
+                return self._fallback.get_track_details(track_id)
 
         if self.is_spotify_authenticated():
             try:
@@ -1100,13 +1125,13 @@ class SpotifyClient:
                 logger.error(f"Error fetching track details via Spotify: {e}")
                 # Fall through to iTunes fallback
 
-        # iTunes fallback - only if ID is numeric (iTunes format)
+        # Fallback - only if ID is numeric (non-Spotify format)
         if self._is_itunes_id(track_id):
-            logger.debug(f"Using iTunes fallback for track details: {track_id}")
-            result = self._itunes.get_track_details(track_id)
+            logger.debug(f"Using {fallback_src} fallback for track details: {track_id}")
+            result = self._fallback.get_track_details(track_id)
             return result
         else:
-            logger.debug(f"Cannot use iTunes fallback for Spotify track ID: {track_id}")
+            logger.debug(f"Cannot use fallback for Spotify track ID: {track_id}")
             return None
 
     @staticmethod
@@ -1158,10 +1183,11 @@ class SpotifyClient:
     
     @rate_limited
     def get_album(self, album_id: str) -> Optional[Dict[str, Any]]:
-        """Get album information - falls back to iTunes if Spotify not authenticated"""
+        """Get album information - falls back to configured metadata source"""
         # Check cache first
         cache = get_metadata_cache()
-        source = 'itunes' if self._is_itunes_id(album_id) else 'spotify'
+        fallback_src = self._fallback_source
+        source = fallback_src if self._is_itunes_id(album_id) else 'spotify'
         cached = cache.get_entity(source, 'album', album_id)
         if cached:
             if source == 'spotify':
@@ -1171,8 +1197,8 @@ class SpotifyClient:
                 # Simplified album cached by get_artist_albums — treat as cache miss
                 logger.debug(f"Cache hit for album {album_id} lacks tracks, fetching full data")
             else:
-                # iTunes cache hit — delegate to iTunesClient which reconstructs Spotify-compatible format
-                return self._itunes.get_album(album_id)
+                # Fallback cache hit — delegate to fallback client
+                return self._fallback.get_album(album_id)
 
         if self.is_spotify_authenticated():
             try:
@@ -1184,23 +1210,23 @@ class SpotifyClient:
             except Exception as e:
                 _detect_and_set_rate_limit(e, 'get_album')
                 logger.error(f"Error fetching album via Spotify: {e}")
-                # Fall through to iTunes fallback
+                # Fall through to fallback
 
-        # iTunes fallback - only if ID is numeric (iTunes format)
+        # Fallback - only if ID is numeric (non-Spotify format)
         if self._is_itunes_id(album_id):
-            logger.debug(f"Using iTunes fallback for album: {album_id}")
-            result = self._itunes.get_album(album_id)
-            return result
+            logger.debug(f"Using {fallback_src} fallback for album: {album_id}")
+            return self._fallback.get_album(album_id)
         else:
-            logger.debug(f"Cannot use iTunes fallback for Spotify album ID: {album_id}")
+            logger.debug(f"Cannot use fallback for Spotify album ID: {album_id}")
             return None
     
     @rate_limited
     def get_album_tracks(self, album_id: str) -> Optional[Dict[str, Any]]:
-        """Get album tracks - falls back to iTunes if Spotify not authenticated"""
+        """Get album tracks - falls back to configured metadata source"""
         # Cache key uses album_id with '_tracks' suffix to differentiate from album metadata
         cache = get_metadata_cache()
-        source = 'itunes' if self._is_itunes_id(album_id) else 'spotify'
+        fallback_src = self._fallback_source
+        source = fallback_src if self._is_itunes_id(album_id) else 'spotify'
         cache_key = f"{album_id}_tracks"
         cached = cache.get_entity(source, 'album', cache_key)
         if cached:
@@ -1251,13 +1277,13 @@ class SpotifyClient:
                 logger.error(f"Error fetching album tracks via Spotify: {e}")
                 # Fall through to iTunes fallback
 
-        # iTunes fallback - only if ID is numeric (iTunes format)
+        # Fallback - only if ID is numeric (non-Spotify format)
         if self._is_itunes_id(album_id):
-            logger.debug(f"Using iTunes fallback for album tracks: {album_id}")
-            result = self._itunes.get_album_tracks(album_id)
+            logger.debug(f"Using {fallback_src} fallback for album tracks: {album_id}")
+            result = self._fallback.get_album_tracks(album_id)
             return result
         else:
-            logger.debug(f"Cannot use iTunes fallback for Spotify album ID: {album_id}")
+            logger.debug(f"Cannot use fallback for Spotify album ID: {album_id}")
             return None
     
     @rate_limited
@@ -1293,12 +1319,12 @@ class SpotifyClient:
                 logger.error(f"Error fetching artist albums via Spotify: {e}")
                 # Fall through to iTunes fallback
 
-        # iTunes fallback - only if ID is numeric (iTunes format)
+        # Fallback - only if ID is numeric (non-Spotify format)
         if self._is_itunes_id(artist_id):
-            logger.debug(f"Using iTunes fallback for artist albums: {artist_id}")
-            return self._itunes.get_artist_albums(artist_id, album_type, limit)
+            logger.debug(f"Using {self._fallback_source} fallback for artist albums: {artist_id}")
+            return self._fallback.get_artist_albums(artist_id, album_type, limit)
         else:
-            logger.debug(f"Cannot use iTunes fallback for Spotify artist ID: {artist_id}")
+            logger.debug(f"Cannot use fallback for Spotify artist ID: {artist_id}")
             return []
 
     @rate_limited
@@ -1315,23 +1341,24 @@ class SpotifyClient:
     @rate_limited
     def get_artist(self, artist_id: str) -> Optional[Dict[str, Any]]:
         """
-        Get full artist details - falls back to iTunes if Spotify not authenticated.
+        Get full artist details - falls back to configured metadata source.
 
         Args:
-            artist_id: Artist ID (Spotify or iTunes depending on authentication)
+            artist_id: Artist ID (Spotify or fallback source depending on authentication)
 
         Returns:
             Dictionary with artist data including images, genres, popularity
         """
         # Check cache first (works even during rate limit bans)
         cache = get_metadata_cache()
-        source = 'itunes' if self._is_itunes_id(artist_id) else 'spotify'
+        fallback_src = self._fallback_source
+        source = fallback_src if self._is_itunes_id(artist_id) else 'spotify'
         cached = cache.get_entity(source, 'artist', artist_id)
         if cached:
             if source == 'spotify':
                 return cached  # Spotify raw format is the expected format
-            # iTunes cache hit — delegate to iTunesClient which reconstructs Spotify-compatible format
-            return self._itunes.get_artist(artist_id)
+            # Fallback cache hit — delegate to fallback client which reconstructs Spotify-compatible format
+            return self._fallback.get_artist(artist_id)
 
         if self.is_spotify_authenticated():
             try:
@@ -1344,13 +1371,12 @@ class SpotifyClient:
                 logger.error(f"Error fetching artist via Spotify: {e}")
                 # Fall through to iTunes fallback
 
-        # iTunes fallback - only if ID is numeric (iTunes format)
+        # Fallback - only if ID is numeric (non-Spotify format)
         if self._is_itunes_id(artist_id):
-            logger.debug(f"Using iTunes fallback for artist: {artist_id}")
-            result = self._itunes.get_artist(artist_id)
-            return result
+            logger.debug(f"Using {fallback_src} fallback for artist: {artist_id}")
+            return self._fallback.get_artist(artist_id)
         else:
-            logger.debug(f"Cannot use iTunes fallback for Spotify artist ID: {artist_id}")
+            logger.debug(f"Cannot use fallback for Spotify artist ID: {artist_id}")
             return None
 
     @rate_limited

core/watchlist_scanner.py

@@ -29,6 +29,21 @@ ITUNES_MAX_RETRIES = 3
 ITUNES_BASE_DELAY = 1.0  # Base delay in seconds for exponential backoff
 
 
+def _get_fallback_metadata_client():
+    """Get the configured metadata fallback client (iTunes or Deezer)."""
+    try:
+        from config.settings import config_manager
+        source = config_manager.get('metadata.fallback_source', 'itunes') or 'itunes'
+        if source == 'deezer':
+            from core.deezer_client import DeezerClient
+            return DeezerClient(), 'deezer'
+        from core.itunes_client import iTunesClient
+        return iTunesClient(), 'itunes'
+    except Exception:
+        from core.itunes_client import iTunesClient
+        return iTunesClient(), 'itunes'
+
+
 def itunes_api_call_with_retry(func, *args, max_retries=ITUNES_MAX_RETRIES, **kwargs):
     """
     Execute an iTunes API call with exponential backoff retry logic.
@@ -402,29 +417,38 @@ class WatchlistScanner:
             else:
                 logger.warning(f"No Spotify ID for {watchlist_artist.artist_name}, cannot scan with Spotify")
                 return (None, None, None)
-        else:  # itunes
-            if watchlist_artist.itunes_artist_id:
-                return (self.metadata_service.itunes, watchlist_artist.itunes_artist_id, 'itunes')
+        else:  # itunes or deezer fallback
+            fallback_source = provider  # 'itunes' or 'deezer'
+            fallback_client = self.metadata_service.itunes  # May be iTunesClient or DeezerClient
+            # Pick the right stored ID for the active fallback source
+            stored_id = watchlist_artist.deezer_artist_id if fallback_source == 'deezer' else watchlist_artist.itunes_artist_id
+            if stored_id:
+                return (fallback_client, stored_id, fallback_source)
             else:
-                # No iTunes ID stored - search by name and cache it
-                logger.info(f"No iTunes ID for {watchlist_artist.artist_name}, searching by name...")
+                # No ID stored for this source - search by name and cache it
+                logger.info(f"No {fallback_source} ID for {watchlist_artist.artist_name}, searching by name...")
                 try:
-                    itunes_client = self.metadata_service.itunes
-                    search_results = itunes_client.search_artists(watchlist_artist.artist_name, limit=1)
+                    search_results = fallback_client.search_artists(watchlist_artist.artist_name, limit=1)
                     if search_results and len(search_results) > 0:
-                        itunes_id = search_results[0].id
-                        logger.info(f"Found iTunes ID {itunes_id} for {watchlist_artist.artist_name}")
-                        # Cache the iTunes ID in the database for future use
-                        self.database.update_watchlist_artist_itunes_id(
-                            watchlist_artist.spotify_artist_id or str(watchlist_artist.id),
-                            itunes_id
-                        )
-                        return (itunes_client, itunes_id, 'itunes')
+                        found_id = search_results[0].id
+                        logger.info(f"Found {fallback_source} ID {found_id} for {watchlist_artist.artist_name}")
+                        # Cache the ID in the database for future use
+                        if fallback_source == 'deezer':
+                            self.database.update_watchlist_artist_deezer_id(
+                                watchlist_artist.spotify_artist_id or str(watchlist_artist.id),
+                                found_id
+                            )
+                        else:
+                            self.database.update_watchlist_artist_itunes_id(
+                                watchlist_artist.spotify_artist_id or str(watchlist_artist.id),
+                                found_id
+                            )
+                        return (fallback_client, found_id, fallback_source)
                     else:
-                        logger.warning(f"Could not find {watchlist_artist.artist_name} on iTunes")
+                        logger.warning(f"Could not find {watchlist_artist.artist_name} on {fallback_source}")
                         return (None, None, None)
                 except Exception as e:
-                    logger.error(f"Error searching iTunes for {watchlist_artist.artist_name}: {e}")
+                    logger.error(f"Error searching {fallback_source} for {watchlist_artist.artist_name}: {e}")
                     return (None, None, None)
 
     def get_active_client_and_artist_id(self, watchlist_artist: WatchlistArtist):
@@ -1551,13 +1575,12 @@ class WatchlistScanner:
 
             logger.info(f"Found {len(similar_artist_names)} similar artists from MusicMap")
 
-            # Get iTunes client for matching
-            from core.itunes_client import iTunesClient
-            itunes_client = iTunesClient()
+            # Get fallback metadata client for matching (iTunes or Deezer)
+            itunes_client, fallback_source = _get_fallback_metadata_client()
 
             # Get the searched artist's IDs to exclude them
             searched_spotify_id = None
-            searched_itunes_id = None
+            searched_fallback_id = None
             try:
                 # Try Spotify search
                 if self.spotify_client and self.spotify_client.is_spotify_authenticated():
@@ -1568,14 +1591,14 @@ class WatchlistScanner:
                 logger.debug(f"Could not get searched artist Spotify ID: {e}")
 
             try:
-                # Try iTunes search
-                itunes_results = itunes_client.search_artists(artist_name, limit=1)
-                if itunes_results and len(itunes_results) > 0:
-                    searched_itunes_id = itunes_results[0].id
+                # Try fallback source (iTunes/Deezer) search
+                fallback_results = itunes_client.search_artists(artist_name, limit=1)
+                if fallback_results and len(fallback_results) > 0:
+                    searched_fallback_id = fallback_results[0].id
             except Exception as e:
-                logger.debug(f"Could not get searched artist iTunes ID: {e}")
+                logger.debug(f"Could not get searched artist {fallback_source} ID: {e}")
 
-            # Match each artist to both Spotify and iTunes
+            # Match each artist to both Spotify and fallback source (iTunes/Deezer)
             matched_artists = []
             seen_names = set()  # Track seen artist names to prevent duplicates
 
@@ -1590,6 +1613,7 @@ class WatchlistScanner:
                         'name': artist_name_to_match,
                         'spotify_id': None,
                         'itunes_id': None,
+                        'deezer_id': None,
                         'image_url': None,
                         'genres': [],
                         'popularity': 0
@@ -1611,42 +1635,48 @@ class WatchlistScanner:
                         except Exception as e:
                             logger.debug(f"Spotify match failed for {artist_name_to_match}: {e}")
 
-                    # Try to match on iTunes (with retry for rate limiting)
+                    # Try to match on fallback source (iTunes/Deezer) with retry for rate limiting
                     try:
-                        itunes_results = itunes_api_call_with_retry(
+                        fallback_results = itunes_api_call_with_retry(
                             itunes_client.search_artists, artist_name_to_match, limit=1
                         )
-                        if itunes_results and len(itunes_results) > 0:
-                            itunes_artist = itunes_results[0]
+                        if fallback_results and len(fallback_results) > 0:
+                            fallback_artist = fallback_results[0]
                             # Skip if this is the searched artist
-                            if itunes_artist.id != searched_itunes_id:
-                                artist_data['itunes_id'] = itunes_artist.id
-                                # Use iTunes name if we don't have Spotify
+                            if fallback_artist.id != searched_fallback_id:
+                                # Store under the appropriate key based on fallback source
+                                if fallback_source == 'deezer':
+                                    artist_data['deezer_id'] = fallback_artist.id
+                                else:
+                                    artist_data['itunes_id'] = fallback_artist.id
+                                # Use fallback name if we don't have Spotify
                                 if not artist_data['spotify_id']:
-                                    artist_data['name'] = itunes_artist.name
-                                # Use iTunes genres if we don't have Spotify genres
-                                if not artist_data['genres'] and hasattr(itunes_artist, 'genres'):
-                                    artist_data['genres'] = itunes_artist.genres
+                                    artist_data['name'] = fallback_artist.name
+                                # Use fallback genres if we don't have Spotify genres
+                                if not artist_data['genres'] and hasattr(fallback_artist, 'genres'):
+                                    artist_data['genres'] = fallback_artist.genres
                         else:
-                            logger.info(f"  [iTunes] No match found for: {artist_name_to_match}")
+                            logger.info(f"  [{fallback_source}] No match found for: {artist_name_to_match}")
                     except Exception as e:
-                        logger.info(f"  [iTunes] Match failed for {artist_name_to_match}: {e}")
+                        logger.info(f"  [{fallback_source}] Match failed for {artist_name_to_match}: {e}")
 
                     # Only add if we got at least one ID
-                    if artist_data['spotify_id'] or artist_data['itunes_id']:
+                    fallback_id_key = 'deezer_id' if fallback_source == 'deezer' else 'itunes_id'
+                    if artist_data['spotify_id'] or artist_data.get(fallback_id_key):
                         seen_names.add(name_lower)
                         matched_artists.append(artist_data)
-                        logger.debug(f"  Matched: {artist_data['name']} (Spotify: {artist_data['spotify_id']}, iTunes: {artist_data['itunes_id']})")
+                        logger.debug(f"  Matched: {artist_data['name']} (Spotify: {artist_data['spotify_id']}, {fallback_source}: {artist_data.get(fallback_id_key)})")
 
                 except Exception as match_error:
                     logger.debug(f"Error matching {artist_name_to_match}: {match_error}")
                     continue
 
             # Log detailed matching statistics
-            itunes_matched = sum(1 for a in matched_artists if a.get('itunes_id'))
+            fallback_id_key = 'deezer_id' if fallback_source == 'deezer' else 'itunes_id'
+            fallback_matched = sum(1 for a in matched_artists if a.get(fallback_id_key))
             spotify_matched = sum(1 for a in matched_artists if a.get('spotify_id'))
-            both_matched = sum(1 for a in matched_artists if a.get('itunes_id') and a.get('spotify_id'))
-            logger.info(f"Matched {len(matched_artists)} similar artists - iTunes: {itunes_matched}, Spotify: {spotify_matched}, Both: {both_matched}")
+            both_matched = sum(1 for a in matched_artists if a.get(fallback_id_key) and a.get('spotify_id'))
+            logger.info(f"Matched {len(matched_artists)} similar artists - {fallback_source}: {fallback_matched}, Spotify: {spotify_matched}, Both: {both_matched}")
             return matched_artists
 
         except requests.exceptions.RequestException as e:
@@ -1669,40 +1699,42 @@ class WatchlistScanner:
             Number of similar artists updated with iTunes IDs
         """
         try:
-            # Get similar artists that are missing iTunes IDs
-            similar_artists = self.database.get_similar_artists_missing_itunes_ids(source_artist_id, profile_id=profile_id)
+            # Get fallback metadata client (iTunes or Deezer)
+            fallback_client, fallback_source = _get_fallback_metadata_client()
+
+            # Get similar artists that are missing IDs for the active fallback source
+            similar_artists = self.database.get_similar_artists_missing_fallback_ids(source_artist_id, fallback_source, profile_id=profile_id)
 
             if not similar_artists:
                 return 0
 
-            logger.info(f"Backfilling iTunes IDs for {len(similar_artists)} similar artists")
-
-            # Get iTunes client
-            from core.itunes_client import iTunesClient
-            itunes_client = iTunesClient()
+            logger.info(f"Backfilling {fallback_source} IDs for {len(similar_artists)} similar artists")
 
             updated_count = 0
             for similar_artist in similar_artists:
                 try:
-                    # Search iTunes by artist name
-                    itunes_results = itunes_client.search_artists(similar_artist.similar_artist_name, limit=1)
-                    if itunes_results and len(itunes_results) > 0:
-                        itunes_id = itunes_results[0].id
-                        # Update the similar artist with the iTunes ID
-                        if self.database.update_similar_artist_itunes_id(similar_artist.id, itunes_id):
+                    results = fallback_client.search_artists(similar_artist.similar_artist_name, limit=1)
+                    if results and len(results) > 0:
+                        found_id = results[0].id
+                        # Update the similar artist with the correct source ID
+                        if fallback_source == 'deezer':
+                            success = self.database.update_similar_artist_deezer_id(similar_artist.id, found_id)
+                        else:
+                            success = self.database.update_similar_artist_itunes_id(similar_artist.id, found_id)
+                        if success:
                             updated_count += 1
-                            logger.debug(f"  Backfilled iTunes ID {itunes_id} for {similar_artist.similar_artist_name}")
+                            logger.debug(f"  Backfilled {fallback_source} ID {found_id} for {similar_artist.similar_artist_name}")
                 except Exception as e:
-                    logger.debug(f"  Could not backfill iTunes ID for {similar_artist.similar_artist_name}: {e}")
+                    logger.debug(f"  Could not backfill {fallback_source} ID for {similar_artist.similar_artist_name}: {e}")
                     continue
 
             if updated_count > 0:
-                logger.info(f"Backfilled {updated_count} similar artists with iTunes IDs")
+                logger.info(f"Backfilled {updated_count} similar artists with {fallback_source} IDs")
 
             return updated_count
 
         except Exception as e:
-            logger.error(f"Error backfilling similar artists iTunes IDs: {e}")
+            logger.error(f"Error backfilling similar artists {fallback_source if 'fallback_source' in dir() else 'fallback'} IDs: {e}")
             return 0
 
     def update_similar_artists(self, watchlist_artist: WatchlistArtist, limit: int = 10, profile_id: int = 1) -> bool:
@@ -1730,7 +1762,7 @@ class WatchlistScanner:
             stored_count = 0
             for rank, similar_artist in enumerate(similar_artists, 1):
                 try:
-                    # similar_artist has 'name', 'spotify_id', 'itunes_id', 'image_url', 'genres', 'popularity'
+                    # similar_artist has 'name', 'spotify_id', 'itunes_id', 'deezer_id', 'image_url', 'genres', 'popularity'
                     success = self.database.add_or_update_similar_artist(
                         source_artist_id=source_artist_id,
                         similar_artist_name=similar_artist['name'],
@@ -1740,12 +1772,15 @@ class WatchlistScanner:
                         profile_id=profile_id,
                         image_url=similar_artist.get('image_url'),
                         genres=similar_artist.get('genres'),
-                        popularity=similar_artist.get('popularity', 0)
+                        popularity=similar_artist.get('popularity', 0),
+                        similar_artist_deezer_id=similar_artist.get('deezer_id')
                     )
 
                     if success:
                         stored_count += 1
-                        logger.debug(f"  #{rank}: {similar_artist['name']} (Spotify: {similar_artist.get('spotify_id')}, iTunes: {similar_artist.get('itunes_id')})")
+                        fallback_id = similar_artist.get('deezer_id') or similar_artist.get('itunes_id')
+                        fallback_label = 'Deezer' if similar_artist.get('deezer_id') else 'iTunes'
+                        logger.debug(f"  #{rank}: {similar_artist['name']} (Spotify: {similar_artist.get('spotify_id')}, {fallback_label}: {fallback_id})")
 
                 except Exception as e:
                     logger.warning(f"Error storing similar artist {similar_artist.get('name', 'Unknown')}: {e}")
@@ -1795,16 +1830,15 @@ class WatchlistScanner:
             # Determine which sources are available
             spotify_available = self.spotify_client and self.spotify_client.is_spotify_authenticated()
 
-            # Import iTunes client for fallback
-            from core.itunes_client import iTunesClient
-            itunes_client = iTunesClient()
-            itunes_available = True  # iTunes is always available (no auth needed)
+            # Import fallback metadata client (iTunes or Deezer)
+            itunes_client, fallback_source = _get_fallback_metadata_client()
+            fallback_available = True  # Fallback source is always available (no auth needed)
 
-            if not spotify_available and not itunes_available:
+            if not spotify_available and not fallback_available:
                 logger.warning("No music sources available to populate discovery pool")
                 return
 
-            logger.info(f"Sources available - Spotify: {spotify_available}, iTunes: {itunes_available}")
+            logger.info(f"Sources available - Spotify: {spotify_available}, {fallback_source}: {fallback_available}")
 
             # Get top similar artists for this profile's watchlist (ordered by occurrence_count)
             similar_artists = self.database.get_top_similar_artists(limit=top_artists_limit, profile_id=profile_id)
@@ -1834,25 +1868,28 @@ class WatchlistScanner:
                         progress_callback('artist', f'{similar_artist.similar_artist_name} ({artist_idx}/{len(similar_artists)})')
 
                     # Build list of sources to process for this artist
-                    # iTunes is ALWAYS processed (baseline), Spotify is added if authenticated
+                    # Fallback source (iTunes/Deezer) is ALWAYS processed (baseline), Spotify is added if authenticated
                     sources_to_process = []
 
-                    # Always add iTunes first (baseline source)
-                    itunes_id = similar_artist.similar_artist_itunes_id
-                    if not itunes_id:
-                        # On-the-fly lookup for missing iTunes ID (seamless provider switching)
+                    # Always add fallback source first (baseline source)
+                    fallback_id = similar_artist.similar_artist_itunes_id if fallback_source == 'itunes' else getattr(similar_artist, 'similar_artist_deezer_id', None)
+                    if not fallback_id:
+                        # On-the-fly lookup for missing fallback ID (seamless provider switching)
                         try:
-                            itunes_results = itunes_client.search_artists(similar_artist.similar_artist_name, limit=1)
-                            if itunes_results and len(itunes_results) > 0:
-                                itunes_id = itunes_results[0].id
+                            fallback_results = itunes_client.search_artists(similar_artist.similar_artist_name, limit=1)
+                            if fallback_results and len(fallback_results) > 0:
+                                fallback_id = fallback_results[0].id
                                 # Cache it for future use
-                                self.database.update_similar_artist_itunes_id(similar_artist.id, itunes_id)
-                                logger.debug(f"  Resolved iTunes ID {itunes_id} for {similar_artist.similar_artist_name}")
+                                if fallback_source == 'deezer':
+                                    self.database.update_similar_artist_deezer_id(similar_artist.id, fallback_id)
+                                else:
+                                    self.database.update_similar_artist_itunes_id(similar_artist.id, fallback_id)
+                                logger.debug(f"  Resolved {fallback_source} ID {fallback_id} for {similar_artist.similar_artist_name}")
                         except Exception as e:
-                            logger.debug(f"  Could not resolve iTunes ID for {similar_artist.similar_artist_name}: {e}")
+                            logger.debug(f"  Could not resolve {fallback_source} ID for {similar_artist.similar_artist_name}: {e}")
 
-                    if itunes_id:
-                        sources_to_process.append(('itunes', itunes_id))
+                    if fallback_id:
+                        sources_to_process.append((fallback_source, fallback_id))
 
                     # Add Spotify if authenticated and we have an ID
                     if spotify_available and similar_artist.similar_artist_spotify_id:
@@ -1874,7 +1911,7 @@ class WatchlistScanner:
                                     album_type='album,single,ep',
                                     limit=50
                                 )
-                            else:  # itunes
+                            else:  # itunes or deezer fallback
                                 all_albums = itunes_client.get_artist_albums(
                                     artist_id,
                                     album_type='album,single,ep',
@@ -1892,7 +1929,7 @@ class WatchlistScanner:
                                     artist_data = self.spotify_client.get_artist(artist_id)
                                     if artist_data and 'genres' in artist_data:
                                         artist_genres = artist_data['genres']
-                                else:  # iTunes - genres from artist lookup
+                                else:  # itunes/deezer - genres from artist lookup
                                     artist_data = itunes_client.get_artist(artist_id)
                                     if artist_data and 'genres' in artist_data:
                                         artist_genres = artist_data['genres']
@@ -1938,7 +1975,7 @@ class WatchlistScanner:
                                         if not album_data or 'tracks' not in album_data:
                                             continue
                                         tracks = album_data['tracks'].get('items', [])
-                                    else:  # itunes
+                                    else:  # itunes or deezer fallback
                                         album_data = itunes_client.get_album(album.id)
                                         if not album_data:
                                             continue
@@ -1978,9 +2015,9 @@ class WatchlistScanner:
                                             }
 
                                             # Build track data for discovery pool with source-specific IDs
-                                            # iTunes has no popularity data — synthesize from recency + occurrence
+                                            # iTunes/Deezer have no popularity data — synthesize from recency + occurrence
                                             raw_popularity = album_data.get('popularity', 0)
-                                            if source == 'itunes' and raw_popularity == 0:
+                                            if source in ('itunes', 'deezer') and raw_popularity == 0:
                                                 # Base 45, boost by recency and artist occurrence count
                                                 synth_pop = 45
                                                 if is_new:
@@ -2022,6 +2059,10 @@ class WatchlistScanner:
                                                 track_data['spotify_track_id'] = track.get('id')
                                                 track_data['spotify_album_id'] = album_data.get('id')
                                                 track_data['spotify_artist_id'] = similar_artist.similar_artist_spotify_id
+                                            elif source == 'deezer':
+                                                track_data['deezer_track_id'] = track.get('id')
+                                                track_data['deezer_album_id'] = album_data.get('id')
+                                                track_data['deezer_artist_id'] = getattr(similar_artist, 'similar_artist_deezer_id', None)
                                             else:  # itunes
                                                 track_data['itunes_track_id'] = track.get('id')
                                                 track_data['itunes_album_id'] = album_data.get('id')
@@ -2100,22 +2141,22 @@ class WatchlistScanner:
                                 except Exception as e:
                                     logger.debug(f"Spotify search failed for {album_row['title']}: {e}")
 
-                            # Fall back to iTunes if Spotify didn't work
-                            if not tracks and itunes_available:
+                            # Fall back to fallback source (iTunes/Deezer) if Spotify didn't work
+                            if not tracks and fallback_available:
                                 try:
                                     search_results = itunes_client.search_albums(query, limit=1)
                                     if search_results and len(search_results) > 0:
-                                        itunes_album = search_results[0]
-                                        album_data = itunes_client.get_album(itunes_album.id)
+                                        fallback_album = search_results[0]
+                                        album_data = itunes_client.get_album(fallback_album.id)
                                         if album_data:
-                                            tracks_data = itunes_client.get_album_tracks(itunes_album.id)
+                                            tracks_data = itunes_client.get_album_tracks(fallback_album.id)
                                             tracks = tracks_data.get('items', []) if tracks_data else []
-                                            db_source = 'itunes'
-                                            # For iTunes, artist ID is in the album data
+                                            db_source = fallback_source
+                                            # Artist ID is in the album data
                                             if album_data.get('artists'):
                                                 artist_id_for_genres = album_data['artists'][0].get('id')
                                 except Exception as e:
-                                    logger.debug(f"iTunes search failed for {album_row['title']}: {e}")
+                                    logger.debug(f"{fallback_source} search failed for {album_row['title']}: {e}")
 
                             if not tracks or not album_data:
                                 continue
@@ -2177,6 +2218,10 @@ class WatchlistScanner:
                                         track_data['spotify_track_id'] = track.get('id')
                                         track_data['spotify_album_id'] = album_data.get('id')
                                         track_data['spotify_artist_id'] = artist_id_for_genres or ''
+                                    elif db_source == 'deezer':
+                                        track_data['deezer_track_id'] = track.get('id')
+                                        track_data['deezer_album_id'] = album_data.get('id')
+                                        track_data['deezer_artist_id'] = artist_id_for_genres or ''
                                     else:  # itunes
                                         track_data['itunes_track_id'] = track.get('id')
                                         track_data['itunes_album_id'] = album_data.get('id')
@@ -2395,24 +2440,23 @@ class WatchlistScanner:
 
             # 30-day window for recent releases
             cutoff_date = datetime.now() - timedelta(days=30)
-            cached_count = {'spotify': 0, 'itunes': 0}
+            cached_count = {'spotify': 0, 'itunes': 0, 'deezer': 0}
             albums_checked = 0
 
             # Determine available sources
             spotify_available = self.spotify_client and self.spotify_client.is_spotify_authenticated()
 
-            # Get iTunes client
-            from core.itunes_client import iTunesClient
-            itunes_client = iTunesClient()
+            # Get fallback metadata client (iTunes or Deezer)
+            itunes_client, fallback_source = _get_fallback_metadata_client()
 
             # Get artists to check (scoped to profile)
             watchlist_artists = self.database.get_watchlist_artists(profile_id=profile_id)
             similar_artists = self.database.get_top_similar_artists(limit=50, profile_id=profile_id)
 
             logger.info(f"Checking albums from {len(watchlist_artists)} watchlist + {len(similar_artists)} similar artists")
-            logger.info(f"Sources: Spotify={spotify_available}, iTunes=True")
+            logger.info(f"Sources: Spotify={spotify_available}, {fallback_source}=True")
 
-            def process_album(album, artist_name, artist_spotify_id, artist_itunes_id, source):
+            def process_album(album, artist_name, artist_spotify_id, artist_itunes_id, source, artist_deezer_id=None):
                 """Helper to process and cache a single album"""
                 nonlocal albums_checked
                 try:
@@ -2422,7 +2466,7 @@ class WatchlistScanner:
                     if not release_str:
                         return False
 
-                    # Handle iTunes ISO format (2017-12-08T08:00:00Z)
+                    # Handle iTunes/Deezer ISO format (2017-12-08T08:00:00Z)
                     if 'T' in release_str:
                         release_str = release_str.split('T')[0]
 
@@ -2432,10 +2476,12 @@ class WatchlistScanner:
                             album_data = {
                                 'album_spotify_id': album.id if source == 'spotify' else None,
                                 'album_itunes_id': album.id if source == 'itunes' else None,
+                                'album_deezer_id': album.id if source == 'deezer' else None,
                                 'album_name': album.name,
                                 'artist_name': artist_name,
                                 'artist_spotify_id': artist_spotify_id,
                                 'artist_itunes_id': artist_itunes_id,
+                                'artist_deezer_id': artist_deezer_id,
                                 'album_cover_url': album.image_url if hasattr(album, 'image_url') else None,
                                 'release_date': release_str[:10],
                                 'album_type': album.album_type if hasattr(album, 'album_type') else 'album'
@@ -2449,39 +2495,44 @@ class WatchlistScanner:
                 return False
 
             # Track resolution stats
-            itunes_resolved = 0
-            itunes_failed_resolve = 0
+            fallback_resolved = 0
+            fallback_failed_resolve = 0
 
             # Process watchlist artists
             for artist in watchlist_artists:
-                # Always process iTunes (baseline)
-                itunes_id = artist.itunes_artist_id
-                if not itunes_id:
-                    # Try to resolve iTunes ID on-the-fly (with retry for rate limiting)
+                # Always process fallback source (iTunes or Deezer) as baseline
+                fallback_id = artist.itunes_artist_id if fallback_source == 'itunes' else artist.deezer_artist_id
+                if not fallback_id:
+                    # Try to resolve fallback ID on-the-fly (with retry for rate limiting)
                     try:
                         results = itunes_api_call_with_retry(
                             itunes_client.search_artists, artist.artist_name, limit=1
                         )
                         if results and len(results) > 0:
-                            itunes_id = results[0].id
-                            itunes_resolved += 1
-                            logger.debug(f"[iTunes] Resolved ID for {artist.artist_name}: {itunes_id}")
+                            fallback_id = results[0].id
+                            fallback_resolved += 1
+                            logger.debug(f"[{fallback_source}] Resolved ID for {artist.artist_name}: {fallback_id}")
                         else:
-                            itunes_failed_resolve += 1
-                            logger.info(f"[iTunes] No artist found for: {artist.artist_name}")
+                            fallback_failed_resolve += 1
+                            logger.info(f"[{fallback_source}] No artist found for: {artist.artist_name}")
                     except Exception as e:
-                        itunes_failed_resolve += 1
-                        logger.info(f"[iTunes] Failed to resolve {artist.artist_name}: {e}")
+                        fallback_failed_resolve += 1
+                        logger.info(f"[{fallback_source}] Failed to resolve {artist.artist_name}: {e}")
 
-                if itunes_id:
+                if fallback_id:
                     try:
                         albums = itunes_api_call_with_retry(
-                            itunes_client.get_artist_albums, itunes_id, album_type='album,single,ep', limit=20
+                            itunes_client.get_artist_albums, fallback_id, album_type='album,single,ep', limit=20
                         )
                         for album in albums or []:
-                            process_album(album, artist.artist_name, artist.spotify_artist_id, itunes_id, 'itunes')
+                            process_album(
+                                album, artist.artist_name, artist.spotify_artist_id,
+                                fallback_id if fallback_source == 'itunes' else None,
+                                fallback_source,
+                                artist_deezer_id=fallback_id if fallback_source == 'deezer' else None
+                            )
                     except Exception as e:
-                        logger.info(f"[iTunes] Error fetching albums for {artist.artist_name}: {e}")
+                        logger.info(f"[{fallback_source}] Error fetching albums for {artist.artist_name}: {e}")
 
                 # Process Spotify if authenticated
                 if spotify_available and artist.spotify_artist_id:
@@ -2492,7 +2543,7 @@ class WatchlistScanner:
                             limit=20
                         )
                         for album in albums or []:
-                            process_album(album, artist.artist_name, artist.spotify_artist_id, itunes_id, 'spotify')
+                            process_album(album, artist.artist_name, artist.spotify_artist_id, fallback_id if fallback_source == 'itunes' else None, 'spotify')
                     except Exception as e:
                         logger.debug(f"Error fetching Spotify albums for {artist.artist_name}: {e}")
 
@@ -2500,36 +2551,44 @@ class WatchlistScanner:
 
             # Process similar artists
             for artist in similar_artists:
-                # Always process iTunes (baseline)
-                itunes_id = artist.similar_artist_itunes_id
-                if not itunes_id:
-                    # Try to resolve iTunes ID on-the-fly (with retry for rate limiting)
+                # Always process fallback source (iTunes or Deezer) as baseline
+                fallback_id = artist.similar_artist_itunes_id if fallback_source == 'itunes' else getattr(artist, 'similar_artist_deezer_id', None)
+                if not fallback_id:
+                    # Try to resolve fallback ID on-the-fly (with retry for rate limiting)
                     try:
                         results = itunes_api_call_with_retry(
                             itunes_client.search_artists, artist.similar_artist_name, limit=1
                         )
                         if results and len(results) > 0:
-                            itunes_id = results[0].id
+                            fallback_id = results[0].id
                             # Cache for future
-                            self.database.update_similar_artist_itunes_id(artist.id, itunes_id)
-                            itunes_resolved += 1
-                            logger.debug(f"[iTunes] Resolved ID for similar artist {artist.similar_artist_name}: {itunes_id}")
+                            if fallback_source == 'deezer':
+                                self.database.update_similar_artist_deezer_id(artist.id, fallback_id)
+                            else:
+                                self.database.update_similar_artist_itunes_id(artist.id, fallback_id)
+                            fallback_resolved += 1
+                            logger.debug(f"[{fallback_source}] Resolved ID for similar artist {artist.similar_artist_name}: {fallback_id}")
                         else:
-                            itunes_failed_resolve += 1
-                            logger.info(f"[iTunes] No artist found for similar: {artist.similar_artist_name}")
+                            fallback_failed_resolve += 1
+                            logger.info(f"[{fallback_source}] No artist found for similar: {artist.similar_artist_name}")
                     except Exception as e:
-                        itunes_failed_resolve += 1
-                        logger.info(f"[iTunes] Failed to resolve similar {artist.similar_artist_name}: {e}")
+                        fallback_failed_resolve += 1
+                        logger.info(f"[{fallback_source}] Failed to resolve similar {artist.similar_artist_name}: {e}")
 
-                if itunes_id:
+                if fallback_id:
                     try:
                         albums = itunes_api_call_with_retry(
-                            itunes_client.get_artist_albums, itunes_id, album_type='album,single,ep', limit=20
+                            itunes_client.get_artist_albums, fallback_id, album_type='album,single,ep', limit=20
                         )
                         for album in albums or []:
-                            process_album(album, artist.similar_artist_name, artist.similar_artist_spotify_id, itunes_id, 'itunes')
+                            process_album(
+                                album, artist.similar_artist_name, artist.similar_artist_spotify_id,
+                                fallback_id if fallback_source == 'itunes' else None,
+                                fallback_source,
+                                artist_deezer_id=fallback_id if fallback_source == 'deezer' else None
+                            )
                     except Exception as e:
-                        logger.info(f"[iTunes] Error fetching albums for similar {artist.similar_artist_name}: {e}")
+                        logger.info(f"[{fallback_source}] Error fetching albums for similar {artist.similar_artist_name}: {e}")
 
                 # Process Spotify if authenticated
                 if spotify_available and artist.similar_artist_spotify_id:
@@ -2540,15 +2599,15 @@ class WatchlistScanner:
                             limit=20
                         )
                         for album in albums or []:
-                            process_album(album, artist.similar_artist_name, artist.similar_artist_spotify_id, itunes_id, 'spotify')
+                            process_album(album, artist.similar_artist_name, artist.similar_artist_spotify_id, fallback_id if fallback_source == 'itunes' else None, 'spotify')
                     except Exception as e:
                         logger.debug(f"Error fetching Spotify albums for {artist.similar_artist_name}: {e}")
 
                 time.sleep(DELAY_BETWEEN_ARTISTS)
 
-            total_cached = cached_count['spotify'] + cached_count['itunes']
-            logger.info(f"Cached {total_cached} recent albums (Spotify: {cached_count['spotify']}, iTunes: {cached_count['itunes']}) from {albums_checked} albums checked")
-            logger.info(f"[iTunes] ID resolution stats: {itunes_resolved} resolved, {itunes_failed_resolve} failed")
+            total_cached = cached_count['spotify'] + cached_count.get(fallback_source, 0)
+            logger.info(f"Cached {total_cached} recent albums (Spotify: {cached_count['spotify']}, {fallback_source}: {cached_count.get(fallback_source, 0)}) from {albums_checked} albums checked")
+            logger.info(f"[{fallback_source}] ID resolution stats: {fallback_resolved} resolved, {fallback_failed_resolve} failed")
 
         except Exception as e:
             logger.error(f"Error caching discovery recent albums: {e}")
@@ -2566,16 +2625,15 @@ class WatchlistScanner:
         try:
             import random
             from datetime import datetime
-            from core.itunes_client import iTunesClient
 
             logger.info("Curating discovery playlists...")
 
             # Determine available sources
             spotify_available = self.spotify_client and self.spotify_client.is_spotify_authenticated()
-            itunes_client = iTunesClient()
+            itunes_client, fallback_source = _get_fallback_metadata_client()
 
             # Process each available source
-            sources_to_process = ['itunes']  # iTunes always available
+            sources_to_process = [fallback_source]  # Fallback source (iTunes/Deezer) always available
             if spotify_available:
                 sources_to_process.append('spotify')
 
@@ -2609,7 +2667,12 @@ class WatchlistScanner:
                         for album in albums:
                             try:
                                 # Get album data from appropriate source
-                                album_id = album.get('album_spotify_id') if source == 'spotify' else album.get('album_itunes_id')
+                                if source == 'spotify':
+                                    album_id = album.get('album_spotify_id')
+                                elif source == 'deezer':
+                                    album_id = album.get('album_deezer_id')
+                                else:
+                                    album_id = album.get('album_itunes_id')
                                 if not album_id:
                                     continue
 
@@ -2641,8 +2704,8 @@ class WatchlistScanner:
                                     # Calculate track score
                                     recency_score = max(0, 100 - (days_old * 7))
                                     popularity_score = track.get('popularity', album_data.get('popularity', 0))
-                                    # iTunes has no popularity — use recency-based synthetic score
-                                    if source == 'itunes' and popularity_score == 0:
+                                    # iTunes/Deezer have no popularity — use recency-based synthetic score
+                                    if source in ('itunes', 'deezer') and popularity_score == 0:
                                         popularity_score = max(40, 70 - days_old)
                                     is_single = album.get('album_type', 'album') == 'single'
                                     single_bonus = 20 if is_single else 0
@@ -2703,6 +2766,9 @@ class WatchlistScanner:
                             if source == 'spotify':
                                 formatted_track['spotify_track_id'] = track_data['id']
                                 formatted_track['spotify_album_id'] = track_data['album'].get('id', '')
+                            elif source == 'deezer':
+                                formatted_track['deezer_track_id'] = track_data['id']
+                                formatted_track['deezer_album_id'] = track_data['album'].get('id', '')
                             else:
                                 formatted_track['itunes_track_id'] = track_data['id']
                                 formatted_track['itunes_album_id'] = track_data['album'].get('id', '')
@@ -2758,13 +2824,15 @@ class WatchlistScanner:
                             discovery_weekly_tracks.append(track.spotify_track_id)
                         elif source == 'itunes' and track.itunes_track_id:
                             discovery_weekly_tracks.append(track.itunes_track_id)
+                        elif source == 'deezer' and track.deezer_track_id:
+                            discovery_weekly_tracks.append(track.deezer_track_id)
 
                 playlist_key = f'discovery_weekly_{source}'
                 self.database.save_curated_playlist(playlist_key, discovery_weekly_tracks, profile_id=profile_id)
                 logger.info(f"Discovery Weekly ({source}) curated: {len(discovery_weekly_tracks)} tracks")
 
             # Also save without suffix for backward compatibility (use active source)
-            active_source = 'spotify' if spotify_available else 'itunes'
+            active_source = 'spotify' if spotify_available else fallback_source
             release_radar_key = f'release_radar_{active_source}'
             discovery_weekly_key = f'discovery_weekly_{active_source}'
 

database/music_database.py

@@ -87,6 +87,7 @@ class WatchlistArtist:
     updated_at: Optional[datetime] = None
     image_url: Optional[str] = None
     itunes_artist_id: Optional[str] = None  # Cross-provider support
+    deezer_artist_id: Optional[str] = None  # Cross-provider support
     include_albums: bool = True
     include_eps: bool = True
     include_singles: bool = True
@@ -99,7 +100,7 @@ class WatchlistArtist:
 
 @dataclass
 class SimilarArtist:
-    """Similar artist recommendation from Spotify/iTunes"""
+    """Similar artist recommendation from Spotify/iTunes/Deezer"""
     id: int
     source_artist_id: str  # Watchlist artist's database ID
     similar_artist_spotify_id: Optional[str]  # Spotify artist ID (may be None if iTunes-only)
@@ -111,6 +112,7 @@ class SimilarArtist:
     image_url: Optional[str] = None  # Cached artist image
     genres: Optional[List[str]] = None  # Cached genres
     popularity: int = 0  # Cached popularity score
+    similar_artist_deezer_id: Optional[str] = None  # Deezer artist ID
 
 @dataclass
 class DiscoveryTrack:
@@ -122,7 +124,10 @@ class DiscoveryTrack:
     itunes_track_id: Optional[str]  # iTunes track ID (None if Spotify source)
     itunes_album_id: Optional[str]  # iTunes album ID (None if Spotify source)
     itunes_artist_id: Optional[str]  # iTunes artist ID (None if Spotify source)
-    source: str  # 'spotify' or 'itunes'
+    deezer_track_id: Optional[str]  # Deezer track ID (None if non-Deezer source)
+    deezer_album_id: Optional[str]  # Deezer album ID (None if non-Deezer source)
+    deezer_artist_id: Optional[str]  # Deezer artist ID (None if non-Deezer source)
+    source: str  # 'spotify', 'itunes', or 'deezer'
     track_name: str
     artist_name: str
     album_name: str
@@ -141,7 +146,8 @@ class RecentRelease:
     watchlist_artist_id: int
     album_spotify_id: Optional[str]  # Spotify album ID (None if iTunes source)
     album_itunes_id: Optional[str]  # iTunes album ID (None if Spotify source)
-    source: str  # 'spotify' or 'itunes'
+    album_deezer_id: Optional[str]  # Deezer album ID (None if non-Deezer source)
+    source: str  # 'spotify', 'itunes', or 'deezer'
     album_name: str
     release_date: str
     album_cover_url: Optional[str]
@@ -846,6 +852,13 @@ class MusicDatabase:
                 cursor.execute("ALTER TABLE discovery_pool ADD COLUMN source TEXT DEFAULT 'spotify'")
                 logger.info("Added iTunes columns to discovery_pool table for dual-source discovery")
 
+            # Migration: Add Deezer columns to discovery_pool for tri-source discovery
+            if 'deezer_track_id' not in discovery_pool_columns:
+                cursor.execute("ALTER TABLE discovery_pool ADD COLUMN deezer_track_id TEXT")
+                cursor.execute("ALTER TABLE discovery_pool ADD COLUMN deezer_album_id TEXT")
+                cursor.execute("ALTER TABLE discovery_pool ADD COLUMN deezer_artist_id TEXT")
+                logger.info("Added Deezer columns to discovery_pool table")
+
             # Migration: Add iTunes ID to similar_artists for dual-source discovery
             cursor.execute("PRAGMA table_info(similar_artists)")
             similar_artists_columns = [column[1] for column in cursor.fetchall()]
@@ -854,6 +867,10 @@ class MusicDatabase:
                 cursor.execute("ALTER TABLE similar_artists ADD COLUMN similar_artist_itunes_id TEXT")
                 logger.info("Added similar_artist_itunes_id column to similar_artists table")
 
+            if 'similar_artist_deezer_id' not in similar_artists_columns:
+                cursor.execute("ALTER TABLE similar_artists ADD COLUMN similar_artist_deezer_id TEXT")
+                logger.info("Added similar_artist_deezer_id column to similar_artists table")
+
             # Migration: Add iTunes columns to recent_releases for dual-source discovery
             cursor.execute("PRAGMA table_info(recent_releases)")
             recent_releases_columns = [column[1] for column in cursor.fetchall()]
@@ -863,6 +880,11 @@ class MusicDatabase:
                 cursor.execute("ALTER TABLE recent_releases ADD COLUMN source TEXT DEFAULT 'spotify'")
                 logger.info("Added iTunes columns to recent_releases table for dual-source discovery")
 
+            # Migration: Add Deezer column to recent_releases for tri-source discovery
+            if 'album_deezer_id' not in recent_releases_columns:
+                cursor.execute("ALTER TABLE recent_releases ADD COLUMN album_deezer_id TEXT")
+                logger.info("Added album_deezer_id column to recent_releases table")
+
             # Migration: Add iTunes columns to discovery_recent_albums for dual-source discovery
             cursor.execute("PRAGMA table_info(discovery_recent_albums)")
             discovery_recent_albums_columns = [column[1] for column in cursor.fetchall()]
@@ -873,6 +895,12 @@ class MusicDatabase:
                 cursor.execute("ALTER TABLE discovery_recent_albums ADD COLUMN source TEXT DEFAULT 'spotify'")
                 logger.info("Added iTunes columns to discovery_recent_albums table for dual-source discovery")
 
+            # Migration: Add Deezer columns to discovery_recent_albums for tri-source discovery
+            if 'album_deezer_id' not in discovery_recent_albums_columns:
+                cursor.execute("ALTER TABLE discovery_recent_albums ADD COLUMN album_deezer_id TEXT")
+                cursor.execute("ALTER TABLE discovery_recent_albums ADD COLUMN artist_deezer_id TEXT")
+                logger.info("Added Deezer columns to discovery_recent_albums table")
+
             # Migration: Fix NOT NULL constraint on album_spotify_id (required for iTunes-only albums)
             # Check if album_spotify_id has NOT NULL constraint by checking table schema
             cursor.execute("SELECT sql FROM sqlite_master WHERE type='table' AND name='discovery_recent_albums'")
@@ -973,6 +1001,8 @@ class MusicDatabase:
             cursor.execute("CREATE INDEX IF NOT EXISTS idx_discovery_pool_itunes_track ON discovery_pool (itunes_track_id)")
             cursor.execute("CREATE INDEX IF NOT EXISTS idx_discovery_pool_artist ON discovery_pool (spotify_artist_id)")
             cursor.execute("CREATE INDEX IF NOT EXISTS idx_discovery_pool_itunes_artist ON discovery_pool (itunes_artist_id)")
+            cursor.execute("CREATE INDEX IF NOT EXISTS idx_discovery_pool_deezer_track ON discovery_pool (deezer_track_id)")
+            cursor.execute("CREATE INDEX IF NOT EXISTS idx_discovery_pool_deezer_artist ON discovery_pool (deezer_artist_id)")
             cursor.execute("CREATE INDEX IF NOT EXISTS idx_discovery_pool_source ON discovery_pool (source)")
             cursor.execute("CREATE INDEX IF NOT EXISTS idx_discovery_pool_added_date ON discovery_pool (added_date)")
             cursor.execute("CREATE INDEX IF NOT EXISTS idx_discovery_pool_is_new ON discovery_pool (is_new_release)")
@@ -1099,6 +1129,10 @@ class MusicDatabase:
                 cursor.execute("ALTER TABLE watchlist_artists ADD COLUMN itunes_artist_id TEXT")
                 logger.info("Added itunes_artist_id column to watchlist_artists table for cross-provider support")
 
+            if 'deezer_artist_id' not in columns:
+                cursor.execute("ALTER TABLE watchlist_artists ADD COLUMN deezer_artist_id TEXT")
+                logger.info("Added deezer_artist_id column to watchlist_artists table for cross-provider support")
+
         except Exception as e:
             logger.error(f"Error adding itunes_artist_id column to watchlist_artists: {e}")
             # Don't raise - this is a migration, database can still function
@@ -5428,28 +5462,63 @@ class MusicDatabase:
             return 0
 
     # Watchlist operations
-    def add_artist_to_watchlist(self, artist_id: str, artist_name: str, profile_id: int = 1) -> bool:
+    def add_artist_to_watchlist(self, artist_id: str, artist_name: str, profile_id: int = 1, source: str = None) -> bool:
         """Add an artist to the watchlist for monitoring new releases.
 
-        Automatically detects if artist_id is a Spotify ID (alphanumeric) or iTunes ID (numeric).
+        Automatically detects if artist_id is a Spotify ID (alphanumeric) or iTunes/Deezer ID (numeric).
+        If the artist already exists (by name match), updates the existing row with the new source ID.
         """
         try:
             with self._get_connection() as conn:
                 cursor = conn.cursor()
 
-                # Detect ID type: iTunes IDs are purely numeric, Spotify IDs are alphanumeric
-                is_itunes_id = artist_id.isdigit()
+                # Check if artist already exists by name (case-insensitive) for this profile
+                cursor.execute("""
+                    SELECT id, spotify_artist_id, itunes_artist_id, deezer_artist_id
+                    FROM watchlist_artists
+                    WHERE LOWER(artist_name) = LOWER(?) AND profile_id = ?
+                    LIMIT 1
+                """, (artist_name, profile_id))
+                existing = cursor.fetchone()
 
-                if is_itunes_id:
+                # Detect source: explicit source param, or infer from ID format
+                if not source:
+                    source = 'itunes' if artist_id.isdigit() else 'spotify'
+
+                if existing:
+                    # Artist already on watchlist — update with new source ID if missing
+                    col_map = {'spotify': 'spotify_artist_id', 'itunes': 'itunes_artist_id', 'deezer': 'deezer_artist_id'}
+                    col = col_map.get(source)
+                    if col and not existing[col]:
+                        cursor.execute(f"""
+                            UPDATE watchlist_artists
+                            SET {col} = ?, updated_at = CURRENT_TIMESTAMP
+                            WHERE id = ?
+                        """, (artist_id, existing['id']))
+                        conn.commit()
+                        logger.info(f"Updated existing watchlist artist '{artist_name}' with {source} ID: {artist_id}")
+                    else:
+                        logger.info(f"Artist '{artist_name}' already on watchlist (profile: {profile_id})")
+                    return True
+
+                # New artist — insert with the appropriate ID column
+                if source == 'deezer':
                     cursor.execute("""
-                        INSERT OR REPLACE INTO watchlist_artists
+                        INSERT INTO watchlist_artists
+                        (deezer_artist_id, artist_name, date_added, updated_at, profile_id)
+                        VALUES (?, ?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP, ?)
+                    """, (artist_id, artist_name, profile_id))
+                    logger.info(f"Added artist '{artist_name}' to watchlist (Deezer ID: {artist_id}, profile: {profile_id})")
+                elif source == 'itunes':
+                    cursor.execute("""
+                        INSERT INTO watchlist_artists
                         (itunes_artist_id, artist_name, date_added, updated_at, profile_id)
                         VALUES (?, ?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP, ?)
                     """, (artist_id, artist_name, profile_id))
                     logger.info(f"Added artist '{artist_name}' to watchlist (iTunes ID: {artist_id}, profile: {profile_id})")
                 else:
                     cursor.execute("""
-                        INSERT OR REPLACE INTO watchlist_artists
+                        INSERT INTO watchlist_artists
                         (spotify_artist_id, artist_name, date_added, updated_at, profile_id)
                         VALUES (?, ?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP, ?)
                     """, (artist_id, artist_name, profile_id))
@@ -5463,23 +5532,23 @@ class MusicDatabase:
             return False
 
     def remove_artist_from_watchlist(self, artist_id: str, profile_id: int = 1) -> bool:
-        """Remove an artist from the watchlist (checks both Spotify and iTunes IDs)"""
+        """Remove an artist from the watchlist (checks Spotify, iTunes, and Deezer IDs)"""
         try:
             with self._get_connection() as conn:
                 cursor = conn.cursor()
 
-                # Get artist name for logging (check both ID columns)
+                # Get artist name for logging (check all ID columns)
                 cursor.execute("""
                     SELECT artist_name FROM watchlist_artists
-                    WHERE (spotify_artist_id = ? OR itunes_artist_id = ?) AND profile_id = ?
-                """, (artist_id, artist_id, profile_id))
+                    WHERE (spotify_artist_id = ? OR itunes_artist_id = ? OR deezer_artist_id = ?) AND profile_id = ?
+                """, (artist_id, artist_id, artist_id, profile_id))
                 result = cursor.fetchone()
                 artist_name = result['artist_name'] if result else "Unknown"
 
                 cursor.execute("""
                     DELETE FROM watchlist_artists
-                    WHERE (spotify_artist_id = ? OR itunes_artist_id = ?) AND profile_id = ?
-                """, (artist_id, artist_id, profile_id))
+                    WHERE (spotify_artist_id = ? OR itunes_artist_id = ? OR deezer_artist_id = ?) AND profile_id = ?
+                """, (artist_id, artist_id, artist_id, profile_id))
 
                 if cursor.rowcount > 0:
                     conn.commit()
@@ -5493,18 +5562,25 @@ class MusicDatabase:
             logger.error(f"Error removing artist from watchlist (ID: {artist_id}): {e}")
             return False
 
-    def is_artist_in_watchlist(self, artist_id: str, profile_id: int = 1) -> bool:
-        """Check if an artist is currently in the watchlist (checks both Spotify and iTunes IDs)"""
+    def is_artist_in_watchlist(self, artist_id: str, profile_id: int = 1, artist_name: str = None) -> bool:
+        """Check if an artist is currently in the watchlist (checks Spotify, iTunes, Deezer IDs and name)"""
         try:
             with self._get_connection() as conn:
                 cursor = conn.cursor()
 
-                # Check both spotify_artist_id and itunes_artist_id columns
-                cursor.execute("""
-                    SELECT 1 FROM watchlist_artists
-                    WHERE (spotify_artist_id = ? OR itunes_artist_id = ?) AND profile_id = ?
-                    LIMIT 1
-                """, (artist_id, artist_id, profile_id))
+                # Check all ID columns and optionally artist name
+                if artist_name:
+                    cursor.execute("""
+                        SELECT 1 FROM watchlist_artists
+                        WHERE (spotify_artist_id = ? OR itunes_artist_id = ? OR deezer_artist_id = ? OR LOWER(artist_name) = LOWER(?)) AND profile_id = ?
+                        LIMIT 1
+                    """, (artist_id, artist_id, artist_id, artist_name, profile_id))
+                else:
+                    cursor.execute("""
+                        SELECT 1 FROM watchlist_artists
+                        WHERE (spotify_artist_id = ? OR itunes_artist_id = ? OR deezer_artist_id = ?) AND profile_id = ?
+                        LIMIT 1
+                    """, (artist_id, artist_id, artist_id, profile_id))
                 result = cursor.fetchone()
 
                 return result is not None
@@ -5526,7 +5602,7 @@ class MusicDatabase:
                 # Build SELECT query based on existing columns
                 base_columns = ['id', 'spotify_artist_id', 'artist_name', 'date_added',
                                'last_scan_timestamp', 'created_at', 'updated_at']
-                optional_columns = ['image_url', 'itunes_artist_id', 'include_albums', 'include_eps', 'include_singles',
+                optional_columns = ['image_url', 'itunes_artist_id', 'deezer_artist_id', 'include_albums', 'include_eps', 'include_singles',
                                    'include_live', 'include_remixes', 'include_acoustic', 'include_compilations',
                                    'include_instrumentals']
 
@@ -5553,6 +5629,7 @@ class MusicDatabase:
                     # Safely get optional columns with defaults (sqlite3.Row uses dict-style access)
                     image_url = row['image_url'] if 'image_url' in existing_columns else None
                     itunes_artist_id = row['itunes_artist_id'] if 'itunes_artist_id' in existing_columns else None
+                    deezer_artist_id = row['deezer_artist_id'] if 'deezer_artist_id' in existing_columns else None
                     include_albums = bool(row['include_albums']) if 'include_albums' in existing_columns else True
                     include_eps = bool(row['include_eps']) if 'include_eps' in existing_columns else True
                     include_singles = bool(row['include_singles']) if 'include_singles' in existing_columns else True
@@ -5572,6 +5649,7 @@ class MusicDatabase:
                         updated_at=datetime.fromisoformat(row['updated_at']) if row['updated_at'] else None,
                         image_url=image_url,
                         itunes_artist_id=itunes_artist_id,
+                        deezer_artist_id=deezer_artist_id,
                         include_albums=include_albums,
                         include_eps=include_eps,
                         include_singles=include_singles,
@@ -5840,6 +5918,27 @@ class MusicDatabase:
             logger.error(f"Error caching watchlist iTunes ID: {e}")
             return False
 
+    def update_watchlist_artist_deezer_id(self, spotify_artist_id: str, deezer_id: str) -> bool:
+        """Update the Deezer artist ID for a watchlist artist by Spotify ID (for cross-provider caching)"""
+        try:
+            with self._get_connection() as conn:
+                cursor = conn.cursor()
+
+                cursor.execute("""
+                    UPDATE watchlist_artists
+                    SET deezer_artist_id = ?, updated_at = CURRENT_TIMESTAMP
+                    WHERE spotify_artist_id = ?
+                """, (deezer_id, spotify_artist_id))
+
+                conn.commit()
+                if cursor.rowcount > 0:
+                    logger.info(f"Cached Deezer ID {deezer_id} for Spotify artist {spotify_artist_id}")
+                return cursor.rowcount > 0
+
+        except Exception as e:
+            logger.error(f"Error caching watchlist Deezer ID: {e}")
+            return False
+
     # === Discovery Feature Methods ===
 
     def add_or_update_similar_artist(self, source_artist_id: str, similar_artist_name: str,
@@ -5849,8 +5948,9 @@ class MusicDatabase:
                                       profile_id: int = 1,
                                       image_url: Optional[str] = None,
                                       genres: Optional[list] = None,
-                                      popularity: int = 0) -> bool:
-        """Add or update a similar artist recommendation (supports both Spotify and iTunes IDs)"""
+                                      popularity: int = 0,
+                                      similar_artist_deezer_id: Optional[str] = None) -> bool:
+        """Add or update a similar artist recommendation (supports Spotify, iTunes, and Deezer IDs)"""
         try:
             with self._get_connection() as conn:
                 cursor = conn.cursor()
@@ -5859,14 +5959,15 @@ class MusicDatabase:
                 # Use artist name as the unique key (allows storing both IDs for same artist)
                 cursor.execute("""
                     INSERT INTO similar_artists
-                    (source_artist_id, similar_artist_spotify_id, similar_artist_itunes_id, similar_artist_name,
+                    (source_artist_id, similar_artist_spotify_id, similar_artist_itunes_id, similar_artist_deezer_id, similar_artist_name,
                      similarity_rank, occurrence_count, last_updated, profile_id,
                      image_url, genres, popularity, metadata_updated_at)
-                    VALUES (?, ?, ?, ?, ?, 1, CURRENT_TIMESTAMP, ?, ?, ?, ?, CURRENT_TIMESTAMP)
+                    VALUES (?, ?, ?, ?, ?, ?, 1, CURRENT_TIMESTAMP, ?, ?, ?, ?, CURRENT_TIMESTAMP)
                     ON CONFLICT(profile_id, source_artist_id, similar_artist_name)
                     DO UPDATE SET
                         similar_artist_spotify_id = COALESCE(excluded.similar_artist_spotify_id, similar_artist_spotify_id),
                         similar_artist_itunes_id = COALESCE(excluded.similar_artist_itunes_id, similar_artist_itunes_id),
+                        similar_artist_deezer_id = COALESCE(excluded.similar_artist_deezer_id, similar_artist_deezer_id),
                         similarity_rank = excluded.similarity_rank,
                         occurrence_count = occurrence_count + 1,
                         last_updated = CURRENT_TIMESTAMP,
@@ -5874,7 +5975,7 @@ class MusicDatabase:
                         genres = COALESCE(excluded.genres, genres),
                         popularity = CASE WHEN excluded.popularity > 0 THEN excluded.popularity ELSE popularity END,
                         metadata_updated_at = CASE WHEN excluded.image_url IS NOT NULL THEN CURRENT_TIMESTAMP ELSE metadata_updated_at END
-                """, (source_artist_id, similar_artist_spotify_id, similar_artist_itunes_id, similar_artist_name,
+                """, (source_artist_id, similar_artist_spotify_id, similar_artist_itunes_id, similar_artist_deezer_id, similar_artist_name,
                       similarity_rank, profile_id, image_url, genres_json, popularity))
 
                 conn.commit()
@@ -5905,7 +6006,8 @@ class MusicDatabase:
                     similar_artist_name=row['similar_artist_name'],
                     similarity_rank=row['similarity_rank'],
                     occurrence_count=row['occurrence_count'],
-                    last_updated=datetime.fromisoformat(row['last_updated'])
+                    last_updated=datetime.fromisoformat(row['last_updated']),
+                    similar_artist_deezer_id=row['similar_artist_deezer_id'] if 'similar_artist_deezer_id' in row.keys() else None,
                 ) for row in rows]
 
         except Exception as e:
@@ -5914,14 +6016,19 @@ class MusicDatabase:
 
     def get_similar_artists_missing_itunes_ids(self, source_artist_id: str, profile_id: int = 1) -> List[SimilarArtist]:
         """Get similar artists for a source that are missing iTunes IDs (for backfill)"""
+        return self.get_similar_artists_missing_fallback_ids(source_artist_id, 'itunes', profile_id)
+
+    def get_similar_artists_missing_fallback_ids(self, source_artist_id: str, fallback_source: str = 'itunes', profile_id: int = 1) -> List[SimilarArtist]:
+        """Get similar artists missing IDs for the given fallback source (for backfill)"""
         try:
+            col = 'similar_artist_deezer_id' if fallback_source == 'deezer' else 'similar_artist_itunes_id'
             with self._get_connection() as conn:
                 cursor = conn.cursor()
 
-                cursor.execute("""
+                cursor.execute(f"""
                     SELECT * FROM similar_artists
                     WHERE source_artist_id = ? AND profile_id = ?
-                    AND (similar_artist_itunes_id IS NULL OR similar_artist_itunes_id = '')
+                    AND ({col} IS NULL OR {col} = '')
                     ORDER BY occurrence_count DESC
                     LIMIT 50
                 """, (source_artist_id, profile_id))
@@ -5931,15 +6038,16 @@ class MusicDatabase:
                     id=row['id'],
                     source_artist_id=row['source_artist_id'],
                     similar_artist_spotify_id=row['similar_artist_spotify_id'],
-                    similar_artist_itunes_id=None,
+                    similar_artist_itunes_id=row['similar_artist_itunes_id'] if 'similar_artist_itunes_id' in row.keys() else None,
                     similar_artist_name=row['similar_artist_name'],
                     similarity_rank=row['similarity_rank'],
                     occurrence_count=row['occurrence_count'],
-                    last_updated=datetime.fromisoformat(row['last_updated'])
+                    last_updated=datetime.fromisoformat(row['last_updated']),
+                    similar_artist_deezer_id=row['similar_artist_deezer_id'] if 'similar_artist_deezer_id' in row.keys() else None,
                 ) for row in rows]
 
         except Exception as e:
-            logger.error(f"Error getting similar artists missing iTunes IDs: {e}")
+            logger.error(f"Error getting similar artists missing {fallback_source} IDs: {e}")
             return []
 
     def update_similar_artist_itunes_id(self, similar_artist_id: int, itunes_id: str) -> bool:
@@ -5961,6 +6069,25 @@ class MusicDatabase:
             logger.error(f"Error updating similar artist iTunes ID: {e}")
             return False
 
+    def update_similar_artist_deezer_id(self, similar_artist_id: int, deezer_id: str) -> bool:
+        """Update a similar artist's Deezer ID (for backfill)"""
+        try:
+            with self._get_connection() as conn:
+                cursor = conn.cursor()
+
+                cursor.execute("""
+                    UPDATE similar_artists
+                    SET similar_artist_deezer_id = ?
+                    WHERE id = ?
+                """, (deezer_id, similar_artist_id))
+
+                conn.commit()
+                return cursor.rowcount > 0
+
+        except Exception as e:
+            logger.error(f"Error updating similar artist Deezer ID: {e}")
+            return False
+
     def update_similar_artist_metadata(self, similar_artist_id: int, image_url: str = None,
                                         genres: list = None, popularity: int = None) -> bool:
         """Cache artist metadata (image, genres, popularity) to avoid repeated API calls"""
@@ -5989,6 +6116,8 @@ class MusicDatabase:
                 genres_json = json.dumps(genres) if genres else None
                 if source == 'spotify':
                     where_clause = "similar_artist_spotify_id = ?"
+                elif source == 'deezer':
+                    where_clause = "similar_artist_deezer_id = ?"
                 else:
                     where_clause = "similar_artist_itunes_id = ?"
                 cursor.execute(f"""
@@ -6091,6 +6220,7 @@ class MusicDatabase:
                         MAX(sa.source_artist_id) as source_artist_id,
                         MAX(sa.similar_artist_spotify_id) as similar_artist_spotify_id,
                         MAX(sa.similar_artist_itunes_id) as similar_artist_itunes_id,
+                        MAX(sa.similar_artist_deezer_id) as similar_artist_deezer_id,
                         sa.similar_artist_name,
                         AVG(sa.similarity_rank) as similarity_rank,
                         SUM(sa.occurrence_count) as occurrence_count,
@@ -6102,6 +6232,7 @@ class MusicDatabase:
                     LEFT JOIN watchlist_artists wa ON (
                         (sa.similar_artist_spotify_id IS NOT NULL AND sa.similar_artist_spotify_id = wa.spotify_artist_id)
                         OR (sa.similar_artist_itunes_id IS NOT NULL AND sa.similar_artist_itunes_id = wa.itunes_artist_id)
+                        OR (sa.similar_artist_deezer_id IS NOT NULL AND sa.similar_artist_deezer_id = wa.deezer_artist_id)
                         OR LOWER(sa.similar_artist_name) = LOWER(wa.artist_name)
                     ) AND wa.profile_id = ?
                     WHERE wa.id IS NULL AND sa.profile_id = ?
@@ -6127,6 +6258,7 @@ class MusicDatabase:
                         source_artist_id=row['source_artist_id'],
                         similar_artist_spotify_id=row['similar_artist_spotify_id'],
                         similar_artist_itunes_id=row['similar_artist_itunes_id'] if 'similar_artist_itunes_id' in row.keys() else None,
+                        similar_artist_deezer_id=row['similar_artist_deezer_id'] if 'similar_artist_deezer_id' in row.keys() else None,
                         similar_artist_name=row['similar_artist_name'],
                         similarity_rank=int(row['similarity_rank']),
                         occurrence_count=row['occurrence_count'],
@@ -6171,6 +6303,9 @@ class MusicDatabase:
                 elif source == 'itunes' and track_data.get('itunes_track_id'):
                     cursor.execute("SELECT COUNT(*) as count FROM discovery_pool WHERE itunes_track_id = ? AND source = 'itunes' AND profile_id = ?",
                                   (track_data['itunes_track_id'], profile_id))
+                elif source == 'deezer' and track_data.get('deezer_track_id'):
+                    cursor.execute("SELECT COUNT(*) as count FROM discovery_pool WHERE deezer_track_id = ? AND source = 'deezer' AND profile_id = ?",
+                                  (track_data['deezer_track_id'], profile_id))
                 else:
                     # Fallback check by track name and artist
                     cursor.execute("SELECT COUNT(*) as count FROM discovery_pool WHERE track_name = ? AND artist_name = ? AND source = ? AND profile_id = ?",
@@ -6187,9 +6322,10 @@ class MusicDatabase:
                     INSERT INTO discovery_pool
                     (spotify_track_id, spotify_album_id, spotify_artist_id,
                      itunes_track_id, itunes_album_id, itunes_artist_id,
+                     deezer_track_id, deezer_album_id, deezer_artist_id,
                      source, track_name, artist_name, album_name, album_cover_url,
                      duration_ms, popularity, release_date, is_new_release, track_data_json, artist_genres, added_date, profile_id)
-                    VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, CURRENT_TIMESTAMP, ?)
+                    VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, CURRENT_TIMESTAMP, ?)
                 """, (
                     track_data.get('spotify_track_id'),
                     track_data.get('spotify_album_id'),
@@ -6197,6 +6333,9 @@ class MusicDatabase:
                     track_data.get('itunes_track_id'),
                     track_data.get('itunes_album_id'),
                     track_data.get('itunes_artist_id'),
+                    track_data.get('deezer_track_id'),
+                    track_data.get('deezer_album_id'),
+                    track_data.get('deezer_artist_id'),
                     source,
                     track_data['track_name'],
                     track_data['artist_name'],
@@ -6284,6 +6423,9 @@ class MusicDatabase:
                     itunes_track_id=row['itunes_track_id'] if 'itunes_track_id' in row_keys else None,
                     itunes_album_id=row['itunes_album_id'] if 'itunes_album_id' in row_keys else None,
                     itunes_artist_id=row['itunes_artist_id'] if 'itunes_artist_id' in row_keys else None,
+                    deezer_track_id=row['deezer_track_id'] if 'deezer_track_id' in row_keys else None,
+                    deezer_album_id=row['deezer_album_id'] if 'deezer_album_id' in row_keys else None,
+                    deezer_artist_id=row['deezer_artist_id'] if 'deezer_artist_id' in row_keys else None,
                     source=row['source'] if 'source' in row_keys else 'spotify',
                     track_name=row['track_name'],
                     artist_name=row['artist_name'],
@@ -6309,14 +6451,17 @@ class MusicDatabase:
 
                 cursor.execute("""
                     INSERT OR REPLACE INTO discovery_recent_albums
-                    (album_spotify_id, album_itunes_id, artist_spotify_id, artist_itunes_id, source,
+                    (album_spotify_id, album_itunes_id, album_deezer_id,
+                     artist_spotify_id, artist_itunes_id, artist_deezer_id, source,
                      album_name, artist_name, album_cover_url, release_date, album_type, cached_date, profile_id)
-                    VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, CURRENT_TIMESTAMP, ?)
+                    VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, CURRENT_TIMESTAMP, ?)
                 """, (
                     album_data.get('album_spotify_id'),
                     album_data.get('album_itunes_id'),
+                    album_data.get('album_deezer_id'),
                     album_data.get('artist_spotify_id'),
                     album_data.get('artist_itunes_id'),
+                    album_data.get('artist_deezer_id'),
                     source,
                     album_data['album_name'],
                     album_data['artist_name'],
@@ -6539,6 +6684,7 @@ class MusicDatabase:
                     watchlist_artist_id=row['watchlist_artist_id'],
                     album_spotify_id=row['album_spotify_id'],
                     album_itunes_id=row['album_itunes_id'] if 'album_itunes_id' in row.keys() else None,
+                    album_deezer_id=row['album_deezer_id'] if 'album_deezer_id' in row.keys() else None,
                     source=row['source'] if 'source' in row.keys() else 'spotify',
                     album_name=row['album_name'],
                     release_date=row['release_date'],

web_server.py

@@ -3147,11 +3147,12 @@ def run_service_test(service, test_config):
                  if temp_client.is_spotify_authenticated():
                      return True, "Spotify connection successful!"
                  else:
-                     # Using iTunes fallback
+                     # Using fallback metadata source
+                     fallback_name = 'Deezer' if _get_metadata_fallback_source() == 'deezer' else 'Apple Music'
                      if spotify_configured:
-                         return True, "Apple Music connection successful! (Spotify configured but not authenticated)"
+                         return True, f"{fallback_name} connection successful! (Spotify configured but not authenticated)"
                      else:
-                         return True, "Apple Music connection successful! (Spotify not configured)"
+                         return True, f"{fallback_name} connection successful! (Spotify not configured)"
             else:
                  return False, "Music service authentication failed. Check credentials and complete OAuth flow in browser if prompted."
         elif service == "tidal":
@@ -3647,13 +3648,13 @@ def get_status():
             if is_rate_limited or cooldown_remaining > 0:
                 # During rate limit or post-ban cooldown, skip the auth probe entirely.
                 # Probing Spotify here would reset the rate limit timer.
-                music_source = 'itunes'  # App uses iTunes during ban — reflect truth
+                music_source = _get_metadata_fallback_source()  # App uses fallback during ban
                 spotify_response_time = 0
             else:
                 spotify_start = time.time()
                 spotify_connected = spotify_client.is_spotify_authenticated() if spotify_client else False
                 spotify_response_time = (time.time() - spotify_start) * 1000
-                music_source = 'spotify' if spotify_connected else 'itunes'
+                music_source = 'spotify' if spotify_connected else _get_metadata_fallback_source()
 
             _status_cache['spotify'] = {
                 'connected': True,  # Always true — iTunes fallback is always available
@@ -4253,7 +4254,7 @@ def handle_settings():
             if 'active_media_server' in new_settings:
                 config_manager.set_active_media_server(new_settings['active_media_server'])
 
-            for service in ['spotify', 'plex', 'jellyfin', 'navidrome', 'soulseek', 'download_source', 'settings', 'database', 'metadata_enhancement', 'file_organization', 'playlist_sync', 'tidal', 'tidal_download', 'qobuz', 'hifi_download', 'listenbrainz', 'acoustid', 'lastfm', 'genius', 'import', 'lossy_copy', 'ui_appearance', 'youtube', 'content_filter', 'itunes', 'm3u_export', 'musicbrainz', 'deezer', 'audiodb']:
+            for service in ['spotify', 'plex', 'jellyfin', 'navidrome', 'soulseek', 'download_source', 'settings', 'database', 'metadata_enhancement', 'file_organization', 'playlist_sync', 'tidal', 'tidal_download', 'qobuz', 'hifi_download', 'listenbrainz', 'acoustid', 'lastfm', 'genius', 'import', 'lossy_copy', 'ui_appearance', 'youtube', 'content_filter', 'itunes', 'm3u_export', 'musicbrainz', 'deezer', 'audiodb', 'metadata']:
                 if service in new_settings:
                     for key, value in new_settings[service].items():
                         config_manager.set(f'{service}.{key}', value)
@@ -4294,6 +4295,8 @@ def handle_settings():
                 genius_worker._init_client()
             if tidal_enrichment_worker:
                 tidal_enrichment_worker.client = tidal_client
+            # Invalidate status cache so next poll reflects new settings (e.g. fallback source change)
+            _status_cache_timestamps['spotify'] = 0
             print("✅ Service clients re-initialized with new settings.")
             return jsonify({"success": True, "message": "Settings saved successfully."})
         except Exception as e:
@@ -5101,7 +5104,7 @@ def test_connection_endpoint():
         current_time = time.time()
         if service == 'spotify':
             _status_cache['spotify']['connected'] = True
-            _status_cache['spotify']['source'] = 'spotify' if (spotify_client and spotify_client.is_spotify_authenticated()) else 'itunes'
+            _status_cache['spotify']['source'] = 'spotify' if (spotify_client and spotify_client.is_spotify_authenticated()) else _get_metadata_fallback_source()
             _status_cache_timestamps['spotify'] = current_time
             print("✅ Updated Spotify status cache after successful test")
         elif service in ['plex', 'jellyfin', 'navidrome']:
@@ -5151,7 +5154,7 @@ def test_dashboard_connection_endpoint():
         current_time = time.time()
         if service == 'spotify':
             _status_cache['spotify']['connected'] = True
-            _status_cache['spotify']['source'] = 'spotify' if (spotify_client and spotify_client.is_spotify_authenticated()) else 'itunes'
+            _status_cache['spotify']['source'] = 'spotify' if (spotify_client and spotify_client.is_spotify_authenticated()) else _get_metadata_fallback_source()
             _status_cache_timestamps['spotify'] = current_time
             print("✅ Updated Spotify status cache after successful dashboard test")
         elif service in ['plex', 'jellyfin', 'navidrome']:
@@ -5819,16 +5822,18 @@ def spotify_disconnect():
             spotify_enrichment_worker.pause()
         spotify_client.disconnect()
         # Immediately update status cache so UI reflects the change
+        fallback_src = _get_metadata_fallback_source()
         _status_cache['spotify'] = {
-            'connected': True,  # iTunes fallback is always available
+            'connected': True,  # Fallback source is always available
             'response_time': 0,
-            'source': 'itunes',
+            'source': fallback_src,
             'rate_limited': False,
             'rate_limit': None
         }
         _status_cache_timestamps['spotify'] = time.time()
-        add_activity_item("🔌", "Spotify Disconnected", "Switched to Apple Music/iTunes metadata source", "Now")
-        return jsonify({'success': True, 'message': 'Spotify disconnected. Now using Apple Music/iTunes.'})
+        fallback_label = 'Deezer' if fallback_src == 'deezer' else 'Apple Music/iTunes'
+        add_activity_item("🔌", "Spotify Disconnected", f"Switched to {fallback_label} metadata source", "Now")
+        return jsonify({'success': True, 'message': f'Spotify disconnected. Now using {fallback_label}.'})
     except Exception as e:
         logger.error(f"Error disconnecting Spotify: {e}")
         return jsonify({'success': False, 'error': str(e)}), 500
@@ -8462,10 +8467,9 @@ def get_artist_image(artist_id):
                 return jsonify({"success": True, "image_url": image_url})
             return jsonify({"success": True, "image_url": None})
         else:
-            # Use iTunes fallback - fetch album art
-            from core.itunes_client import iTunesClient
-            itunes = iTunesClient()
-            image_url = itunes._get_artist_image_from_albums(artist_id)
+            # Use fallback source - fetch album art
+            fallback = _get_metadata_fallback_client()
+            image_url = fallback._get_artist_image_from_albums(artist_id)
             return jsonify({"success": True, "image_url": image_url})
     except Exception as e:
         print(f"Error fetching artist image: {e}")
@@ -8485,9 +8489,9 @@ def get_artist_discography(artist_id):
         # Determine which source to use
         spotify_available = spotify_client and spotify_client.is_spotify_authenticated()
 
-        # Import iTunes client for fallback
-        from core.itunes_client import iTunesClient
-        itunes_client = iTunesClient()
+        # Import fallback client for non-Spotify lookups
+        fallback_client = _get_metadata_fallback_client()
+        fallback_source = _get_metadata_fallback_source()
 
         print(f"🎤 Fetching discography for artist: {artist_id} (name: {artist_name}, spotify: {spotify_available})")
 
@@ -8518,36 +8522,36 @@ def get_artist_discography(artist_id):
             except Exception as e:
                 print(f"Spotify lookup failed: {e}")
 
-        # Try iTunes if Spotify didn't work or if it's a numeric ID
+        # Try fallback source if Spotify didn't work or if it's a numeric ID
         if not albums:
             try:
                 if is_numeric_id:
-                    # It's an iTunes ID, use directly
-                    albums = itunes_client.get_artist_albums(artist_id, album_type='album,single', limit=50)
+                    # It's a numeric ID (iTunes/Deezer), use directly
+                    albums = fallback_client.get_artist_albums(artist_id, album_type='album,single', limit=50)
                     if albums:
-                        active_source = 'itunes'
-                        print(f"📊 Got {len(albums)} albums from iTunes (direct ID)")
+                        active_source = fallback_source
+                        print(f"📊 Got {len(albums)} albums from {fallback_source} (direct ID)")
                 elif artist_name:
-                    # Search iTunes by name
-                    print(f"🔄 Trying iTunes search by name: '{artist_name}'")
-                    itunes_artists = itunes_client.search_artists(artist_name, limit=5)
-                    if itunes_artists:
+                    # Search fallback by name
+                    print(f"🔄 Trying {fallback_source} search by name: '{artist_name}'")
+                    fallback_artists = fallback_client.search_artists(artist_name, limit=5)
+                    if fallback_artists:
                         # Find best match
                         best_match = None
-                        for artist in itunes_artists:
+                        for artist in fallback_artists:
                             if artist.name.lower() == artist_name.lower():
                                 best_match = artist
                                 break
                         if not best_match:
-                            best_match = itunes_artists[0]
+                            best_match = fallback_artists[0]
 
-                        print(f"✅ Found iTunes artist: {best_match.name} (ID: {best_match.id})")
-                        albums = itunes_client.get_artist_albums(best_match.id, album_type='album,single', limit=50)
+                        print(f"✅ Found {fallback_source} artist: {best_match.name} (ID: {best_match.id})")
+                        albums = fallback_client.get_artist_albums(best_match.id, album_type='album,single', limit=50)
                         if albums:
-                            active_source = 'itunes'
-                            print(f"📊 Got {len(albums)} albums from iTunes (name search)")
+                            active_source = fallback_source
+                            print(f"📊 Got {len(albums)} albums from {fallback_source} (name search)")
             except Exception as e:
-                print(f"iTunes lookup failed: {e}")
+                print(f"{fallback_source} lookup failed: {e}")
 
         print(f"📊 Total albums returned: {len(albums)} (source: {active_source})")
         
@@ -9612,11 +9616,10 @@ def enhance_artist_quality(artist_id):
                 except Exception as e:
                     print(f"⚠️ [Enhance] Search match failed for {title}: {e}")
 
-            # iTunes fallback when Spotify unavailable or no match found
+            # Fallback source when Spotify unavailable or no match found
             if not matched_track_data:
                 try:
-                    from core.itunes_client import iTunesClient
-                    itunes_client = iTunesClient()
+                    fallback_client = _get_metadata_fallback_client()
                     itunes_best = None
                     itunes_best_conf = 0.0
 
@@ -9629,7 +9632,7 @@ def enhance_artist_quality(artist_id):
 
                     for search_query in itunes_queries[:3]:
                         try:
-                            itunes_results = itunes_client.search_tracks(search_query, limit=5)
+                            itunes_results = fallback_client.search_tracks(search_query, limit=5)
                             if not itunes_results:
                                 continue
                             for it_track in itunes_results:
@@ -9674,13 +9677,13 @@ def enhance_artist_quality(artist_id):
                             'preview_url': itunes_best.preview_url,
                             'external_urls': itunes_best.external_urls or {},
                         }
-                        print(f"🍎 [Enhance] iTunes fallback match for {title}: {itunes_best.artists[0]} - {itunes_best.name} (conf: {itunes_best_conf:.3f})")
+                        print(f"🍎 [Enhance] Fallback match for {title}: {itunes_best.artists[0]} - {itunes_best.name} (conf: {itunes_best_conf:.3f})")
                 except Exception as e:
-                    print(f"⚠️ [Enhance] iTunes fallback failed for {title}: {e}")
+                    print(f"⚠️ [Enhance] Fallback source failed for {title}: {e}")
 
             if not matched_track_data:
                 failed_count += 1
-                failed_tracks.append({'track_id': track_id, 'title': title, 'reason': 'No Spotify or iTunes match'})
+                failed_tracks.append({'track_id': track_id, 'title': title, 'reason': 'No Spotify or fallback match'})
                 continue
 
             # Add to wishlist with enhance source
@@ -24267,10 +24270,9 @@ def search_itunes_tracks():
         else:
             if hydrabase_worker and dev_mode_enabled:
                 hydrabase_worker.enqueue(query, 'track')
-            from core.itunes_client import iTunesClient
-            itunes_client = iTunesClient()
-            tracks = itunes_client.search_tracks(query, limit=limit)
-            source = 'itunes'
+            fallback_client = _get_metadata_fallback_client()
+            tracks = fallback_client.search_tracks(query, limit=limit)
+            source = _get_metadata_fallback_source()
 
         tracks_dict = [{
             'id': t.id,
@@ -24326,16 +24328,14 @@ def get_itunes_album_tracks(album_id):
             except Exception as e:
                 logger.warning(f"Hydrabase album_tracks failed for '{album_id}', falling back to iTunes: {e}")
 
-        from core.itunes_client import iTunesClient
-
-        itunes_client = iTunesClient()
-        album_data = itunes_client.get_album(album_id)
+        fallback_client = _get_metadata_fallback_client()
+        album_data = fallback_client.get_album(album_id)
 
         if not album_data:
             return jsonify({"error": "Album not found"}), 404
 
         # Get tracks for this album
-        tracks_data = itunes_client.get_album_tracks(album_id)
+        tracks_data = fallback_client.get_album_tracks(album_id)
         tracks = tracks_data.get('items', []) if tracks_data else []
 
         # Format response to match Spotify structure for frontend compatibility
@@ -24348,12 +24348,12 @@ def get_itunes_album_tracks(album_id):
             'album_type': album_data.get('album_type', 'album'),
             'images': album_data.get('images', []),
             'tracks': tracks,
-            'source': 'itunes'
+            'source': _get_metadata_fallback_source()
         }
         return jsonify(album_dict)
 
     except Exception as e:
-        logger.error(f"Error fetching iTunes album tracks: {e}")
+        logger.error(f"Error fetching album tracks: {e}")
         return jsonify({"error": str(e)}), 500
 
 
@@ -24423,15 +24423,14 @@ def get_discover_album(source, album_id):
                 'source': 'spotify'
             })
 
-        elif source == 'itunes':
-            from core.itunes_client import iTunesClient
-            itunes_client = iTunesClient()
+        elif source in ('itunes', 'deezer'):
+            fallback_client = _get_metadata_fallback_client()
 
-            album_data = itunes_client.get_album(album_id)
+            album_data = fallback_client.get_album(album_id)
             if not album_data:
                 return jsonify({"error": "Album not found"}), 404
 
-            tracks_data = itunes_client.get_album_tracks(album_id)
+            tracks_data = fallback_client.get_album_tracks(album_id)
             tracks = tracks_data.get('items', []) if tracks_data else []
 
             return jsonify({
@@ -24443,7 +24442,7 @@ def get_discover_album(source, album_id):
                 'album_type': album_data.get('album_type', 'album'),
                 'images': album_data.get('images', []),
                 'tracks': tracks,
-                'source': 'itunes'
+                'source': source
             })
 
         else:
@@ -25055,17 +25054,16 @@ def _run_playlist_discovery_worker(playlists, automation_id=None):
     try:
         _ew_state = _pause_enrichment_workers('mirrored playlist discovery')
         use_spotify = spotify_client and spotify_client.is_spotify_authenticated()
-        discovery_source = 'spotify' if use_spotify else 'itunes'
+        discovery_source = 'spotify' if use_spotify else _get_metadata_fallback_source()
 
         itunes_client_instance = None
         if not use_spotify:
             try:
-                from core.itunes_client import iTunesClient
-                itunes_client_instance = iTunesClient()
+                itunes_client_instance = _get_metadata_fallback_client()
             except Exception:
-                print("❌ Neither Spotify nor iTunes available for discovery")
+                print(f"❌ Neither Spotify nor {_get_metadata_fallback_source()} available for discovery")
                 _update_automation_progress(automation_id, status='error', progress=100,
-                                            phase='Error', log_line='Neither Spotify nor iTunes available',
+                                            phase='Error', log_line=f'Neither Spotify nor {_get_metadata_fallback_source()} available',
                                             log_type='error')
                 return
 
@@ -25467,13 +25465,12 @@ def _run_tidal_discovery_worker(playlist_id):
 
         # Determine which provider to use
         use_spotify = spotify_client and spotify_client.is_spotify_authenticated()
-        discovery_source = 'spotify' if use_spotify else 'itunes'
+        discovery_source = 'spotify' if use_spotify else _get_metadata_fallback_source()
 
-        # Initialize iTunes client if needed
+        # Initialize fallback client if needed
         itunes_client_instance = None
         if not use_spotify:
-            from core.itunes_client import iTunesClient
-            itunes_client_instance = iTunesClient()
+            itunes_client_instance = _get_metadata_fallback_client()
 
         print(f"🎵 Starting Tidal discovery for: {playlist.name} (using {discovery_source.upper()})")
 
@@ -25567,15 +25564,15 @@ def _run_tidal_discovery_worker(playlist_id):
                     state['spotify_matches'] = successful_discoveries
 
                 elif not use_spotify and track_result and isinstance(track_result, dict):
-                    # iTunes: Function returns a dict with track data (includes 'confidence' key)
+                    # Fallback: Function returns a dict with track data (includes 'confidence' key)
                     match_confidence = track_result.pop('confidence', 0.80)
                     match_data = track_result
-                    match_data['source'] = 'itunes'
-                    # Extract image URL from iTunes album images
-                    _itunes_album = match_data.get('album', {})
-                    _itunes_images = _itunes_album.get('images', []) if isinstance(_itunes_album, dict) else []
-                    if _itunes_images and 'image_url' not in match_data:
-                        match_data['image_url'] = _itunes_images[0].get('url', '')
+                    match_data['source'] = discovery_source
+                    # Extract image URL from album images
+                    _fb_album = match_data.get('album', {})
+                    _fb_images = _fb_album.get('images', []) if isinstance(_fb_album, dict) else []
+                    if _fb_images and 'image_url' not in match_data:
+                        match_data['image_url'] = _fb_images[0].get('url', '')
                     result['spotify_data'] = match_data
                     result['match_data'] = match_data
                     result['status'] = 'found'
@@ -25639,16 +25636,16 @@ def _run_tidal_discovery_worker(playlist_id):
 
 
 def _search_spotify_for_tidal_track(tidal_track, use_spotify=True, itunes_client=None):
-    """Search Spotify/iTunes for a Tidal track using matching_engine for better accuracy
+    """Search Spotify/fallback for a Tidal track using matching_engine for better accuracy
 
     Args:
         tidal_track: The Tidal track to search for
-        use_spotify: If True, use Spotify; if False, use iTunes
-        itunes_client: iTunes client instance (required when use_spotify=False)
+        use_spotify: If True, use Spotify; if False, use fallback source
+        itunes_client: Fallback client instance (required when use_spotify=False)
 
     Returns:
         For Spotify: (Track, raw_data, confidence) tuple or None
-        For iTunes: dict with track data (includes 'confidence' key) or None
+        For fallback: dict with track data (includes 'confidence' key) or None
     """
     if use_spotify:
         if not spotify_client or not spotify_client.is_authenticated():
@@ -25667,7 +25664,7 @@ def _search_spotify_for_tidal_track(tidal_track, use_spotify=True, itunes_client
 
         artist_name = artists[0]  # Use primary artist
         source_duration = getattr(tidal_track, 'duration_ms', 0) or 0
-        source_name = "Spotify" if use_spotify else "iTunes"
+        source_name = "Spotify" if use_spotify else _get_metadata_fallback_source().capitalize()
 
         print(f"🔍 Tidal track: '{artist_name}' - '{track_name}' (searching {source_name})")
 
@@ -25762,7 +25759,7 @@ def _search_spotify_for_tidal_track(tidal_track, use_spotify=True, itunes_client
                 result_artists = best_match.artists if hasattr(best_match, 'artists') else []
                 result_artist = result_artists[0] if result_artists else 'Unknown'
                 result_name = best_match.name if hasattr(best_match, 'name') else 'Unknown'
-                print(f"✅ Final Tidal iTunes match: {result_artist} - {result_name} (confidence: {best_confidence:.3f})")
+                print(f"✅ Final Tidal {source_name} match: {result_artist} - {result_name} (confidence: {best_confidence:.3f})")
 
                 album_name = best_match.album if hasattr(best_match, 'album') else 'Unknown Album'
                 image_url = best_match.image_url if hasattr(best_match, 'image_url') else ''
@@ -25779,7 +25776,7 @@ def _search_spotify_for_tidal_track(tidal_track, use_spotify=True, itunes_client
                         'images': [{'url': image_url, 'height': 300, 'width': 300}] if image_url else []
                     },
                     'duration_ms': duration_ms,
-                    'source': 'itunes',
+                    'source': _get_metadata_fallback_source(),
                     'confidence': best_confidence
                 }
         else:
@@ -25980,6 +25977,22 @@ def _get_deezer_client():
                 _deezer_client_instance = DeezerClient()
     return _deezer_client_instance
 
+def _get_metadata_fallback_source():
+    """Get the configured metadata fallback source ('itunes' or 'deezer')."""
+    try:
+        return config_manager.get('metadata.fallback_source', 'itunes') or 'itunes'
+    except Exception:
+        return 'itunes'
+
+def _get_metadata_fallback_client():
+    """Get the active metadata fallback client based on settings.
+    Returns an iTunesClient or DeezerClient instance with identical interfaces."""
+    source = _get_metadata_fallback_source()
+    if source == 'deezer':
+        return _get_deezer_client()
+    from core.itunes_client import iTunesClient
+    return iTunesClient()
+
 @app.route('/api/deezer/playlist/<playlist_id>', methods=['GET'])
 def get_deezer_playlist(playlist_id):
     """Fetch a Deezer playlist by ID or URL"""
@@ -26371,13 +26384,12 @@ def _run_deezer_discovery_worker(playlist_id):
 
         # Determine which provider to use
         use_spotify = spotify_client and spotify_client.is_spotify_authenticated()
-        discovery_source = 'spotify' if use_spotify else 'itunes'
+        discovery_source = 'spotify' if use_spotify else _get_metadata_fallback_source()
 
-        # Initialize iTunes client if needed
+        # Initialize fallback client if needed
         itunes_client_instance = None
         if not use_spotify:
-            from core.itunes_client import iTunesClient
-            itunes_client_instance = iTunesClient()
+            itunes_client_instance = _get_metadata_fallback_client()
 
         print(f"🎵 Starting Deezer discovery for: {playlist['name']} (using {discovery_source.upper()})")
 
@@ -26514,15 +26526,15 @@ def _run_deezer_discovery_worker(playlist_id):
                     state['spotify_matches'] = successful_discoveries
 
                 elif not use_spotify and track_result and isinstance(track_result, dict):
-                    # iTunes: Function returns a dict with track data (includes 'confidence' key)
+                    # Fallback: Function returns a dict with track data (includes 'confidence' key)
                     match_confidence = track_result.pop('confidence', 0.80)
                     match_data = track_result
-                    match_data['source'] = 'itunes'
-                    # Extract image URL from iTunes album images
-                    _itunes_album = match_data.get('album', {})
-                    _itunes_images = _itunes_album.get('images', []) if isinstance(_itunes_album, dict) else []
-                    if _itunes_images and 'image_url' not in match_data:
-                        match_data['image_url'] = _itunes_images[0].get('url', '')
+                    match_data['source'] = discovery_source
+                    # Extract image URL from album images
+                    _fb_album = match_data.get('album', {})
+                    _fb_images = _fb_album.get('images', []) if isinstance(_fb_album, dict) else []
+                    if _fb_images and 'image_url' not in match_data:
+                        match_data['image_url'] = _fb_images[0].get('url', '')
                     result['spotify_data'] = match_data
                     result['match_data'] = match_data
                     result['status'] = '✅ Found'
@@ -27180,13 +27192,12 @@ def _run_spotify_public_discovery_worker(url_hash):
 
         # Determine which provider to use
         use_spotify = spotify_client and spotify_client.is_spotify_authenticated()
-        discovery_source = 'spotify' if use_spotify else 'itunes'
+        discovery_source = 'spotify' if use_spotify else _get_metadata_fallback_source()
 
-        # Initialize iTunes client if needed
+        # Initialize fallback client if needed
         itunes_client_instance = None
         if not use_spotify:
-            from core.itunes_client import iTunesClient
-            itunes_client_instance = iTunesClient()
+            itunes_client_instance = _get_metadata_fallback_client()
 
         print(f"🎵 Starting Spotify Public discovery for: {playlist['name']} (using {discovery_source.upper()})")
 
@@ -27334,15 +27345,15 @@ def _run_spotify_public_discovery_worker(url_hash):
                     state['spotify_matches'] = successful_discoveries
 
                 elif not use_spotify and track_result and isinstance(track_result, dict):
-                    # iTunes: Function returns a dict with track data (includes 'confidence' key)
+                    # Fallback: Function returns a dict with track data (includes 'confidence' key)
                     match_confidence = track_result.pop('confidence', 0.80)
                     match_data = track_result
-                    match_data['source'] = 'itunes'
-                    # Extract image URL from iTunes album images
-                    _itunes_album = match_data.get('album', {})
-                    _itunes_images = _itunes_album.get('images', []) if isinstance(_itunes_album, dict) else []
-                    if _itunes_images and 'image_url' not in match_data:
-                        match_data['image_url'] = _itunes_images[0].get('url', '')
+                    match_data['source'] = discovery_source
+                    # Extract image URL from album images
+                    _fb_album = match_data.get('album', {})
+                    _fb_images = _fb_album.get('images', []) if isinstance(_fb_album, dict) else []
+                    if _fb_images and 'image_url' not in match_data:
+                        match_data['image_url'] = _fb_images[0].get('url', '')
                     result['spotify_data'] = match_data
                     result['match_data'] = match_data
                     result['status'] = '✅ Found'
@@ -27851,11 +27862,10 @@ def _run_youtube_discovery_worker(url_hash):
 
         # Determine which provider to use (Spotify preferred, iTunes fallback)
         use_spotify = spotify_client and spotify_client.is_spotify_authenticated()
-        discovery_source = 'spotify' if use_spotify else 'itunes'
+        discovery_source = 'spotify' if use_spotify else _get_metadata_fallback_source()
 
-        # Get iTunes client for fallback
-        from core.itunes_client import iTunesClient
-        itunes_client = iTunesClient()
+        # Get fallback client
+        itunes_client = _get_metadata_fallback_client()
 
         print(f"🔍 Starting {discovery_source} discovery for {len(tracks)} YouTube tracks...")
 
@@ -28168,11 +28178,10 @@ def _run_listenbrainz_discovery_worker(state_key):
 
         # Determine which provider to use (Spotify preferred, iTunes fallback)
         use_spotify = spotify_client and spotify_client.is_spotify_authenticated()
-        discovery_source = 'spotify' if use_spotify else 'itunes'
+        discovery_source = 'spotify' if use_spotify else _get_metadata_fallback_source()
 
-        # Get iTunes client for fallback
-        from core.itunes_client import iTunesClient
-        itunes_client = iTunesClient()
+        # Get fallback client
+        itunes_client = _get_metadata_fallback_client()
 
         print(f"🔍 Starting {discovery_source} discovery for {len(tracks)} ListenBrainz tracks...")
 
@@ -30145,43 +30154,48 @@ def add_to_watchlist():
             return jsonify({"success": False, "error": "Missing artist_id or artist_name"}), 400
 
         database = get_database()
-        success = database.add_artist_to_watchlist(artist_id, artist_name, profile_id=get_current_profile_id())
+        # Detect ID type and determine source
+        is_numeric_id = artist_id.isdigit()
+        fallback_source = _get_metadata_fallback_source()
+        source = fallback_source if is_numeric_id else 'spotify'
+        success = database.add_artist_to_watchlist(artist_id, artist_name, profile_id=get_current_profile_id(), source=source)
 
         if success:
-            # Detect ID type: iTunes IDs are purely numeric, Spotify IDs are alphanumeric
-            is_itunes_id = artist_id.isdigit()
-            
+
             # Fetch and cache artist image immediately
             try:
-                if is_itunes_id:
-                    # For iTunes artists, fetch image from iTunes API
-                    # We look up 'album' entity because 'artist' entity doesn't always have artwork
-                    # We fallback to the first album's artwork as the artist image
+                if is_numeric_id:
+                    # For numeric IDs, fetch image from the configured fallback source
                     try:
-                        itunes_url = f"https://itunes.apple.com/lookup?id={artist_id}&entity=album&limit=5"
-                        print(f"🔍 Fetching iTunes artist image: {itunes_url}")
-                        resp = requests.get(itunes_url, timeout=5)
-                        
-                        image_url = None
-                        if resp.status_code == 200:
-                            data = resp.json()
-                            results = data.get('results', [])
-                            
-                            # Iterate results to find one with artwork
-                            for res in results:
-                                if 'artworkUrl100' in res:
-                                    # Get highest res by replacing dimensions
-                                    # iTunes artwork URLs usually end in .../100x100bb.jpg
-                                    image_url = res['artworkUrl100'].replace('100x100', '600x600')
-                                    break
-                        
+                        if fallback_source == 'deezer':
+                            # Deezer artists have direct image URLs
+                            fallback = _get_metadata_fallback_client()
+                            artist_info = fallback.get_artist(artist_id)
+                            image_url = artist_info.get('images', [{}])[0].get('url') if artist_info and artist_info.get('images') else None
+                        else:
+                            # iTunes: look up album entity for artwork
+                            itunes_url = f"https://itunes.apple.com/lookup?id={artist_id}&entity=album&limit=5"
+                            print(f"🔍 Fetching iTunes artist image: {itunes_url}")
+                            resp = requests.get(itunes_url, timeout=5)
+
+                            image_url = None
+                            if resp.status_code == 200:
+                                resp_data = resp.json()
+                                results = resp_data.get('results', [])
+
+                                # Iterate results to find one with artwork
+                                for res in results:
+                                    if 'artworkUrl100' in res:
+                                        image_url = res['artworkUrl100'].replace('100x100', '600x600')
+                                        break
+
                         if image_url:
                             database.update_watchlist_artist_image(artist_id, image_url)
-                            print(f"✅ Cached iTunes artist image for {artist_name}")
+                            print(f"✅ Cached {fallback_source} artist image for {artist_name}")
                         else:
-                            print(f"⚠️ No artwork found for iTunes artist {artist_name}")
-                    except Exception as itunes_error:
-                        print(f"⚠️ Error fetching iTunes artwork: {itunes_error}")
+                            print(f"⚠️ No artwork found for {fallback_source} artist {artist_name}")
+                    except Exception as fb_error:
+                        print(f"⚠️ Error fetching {fallback_source} artwork: {fb_error}")
                 elif spotify_client and spotify_client.is_authenticated():
                     # For Spotify artists, fetch from Spotify API
                     artist_data = spotify_client.get_artist(artist_id)
@@ -30285,27 +30299,39 @@ def add_batch_to_watchlist():
             if not artist_id or not artist_name:
                 continue
 
-            # Check if already watched
-            if database.is_artist_in_watchlist(artist_id, profile_id=get_current_profile_id()):
+            # Check if already watched (by ID or name)
+            if database.is_artist_in_watchlist(artist_id, profile_id=get_current_profile_id(), artist_name=artist_name):
                 skipped += 1
                 continue
 
-            success = database.add_artist_to_watchlist(artist_id, artist_name, profile_id=get_current_profile_id())
+            is_numeric = artist_id.isdigit()
+            fb_source = _get_metadata_fallback_source()
+            src = fb_source if is_numeric else 'spotify'
+            success = database.add_artist_to_watchlist(artist_id, artist_name, profile_id=get_current_profile_id(), source=src)
             if success:
                 added += 1
                 # Cache artist image
                 try:
-                    is_itunes_id = artist_id.isdigit()
-                    if is_itunes_id:
-                        itunes_url = f"https://itunes.apple.com/lookup?id={artist_id}&entity=album&limit=5"
-                        resp = requests.get(itunes_url, timeout=5)
-                        if resp.status_code == 200:
-                            results = resp.json().get('results', [])
-                            for res in results:
-                                if 'artworkUrl100' in res:
-                                    image_url = res['artworkUrl100'].replace('100x100', '600x600')
+                    is_numeric_id = artist_id.isdigit()
+                    if is_numeric_id:
+                        fb_source = _get_metadata_fallback_source()
+                        if fb_source == 'deezer':
+                            fb_client = _get_metadata_fallback_client()
+                            fb_artist = fb_client.get_artist(artist_id)
+                            if fb_artist and fb_artist.get('images'):
+                                image_url = fb_artist['images'][0].get('url')
+                                if image_url:
                                     database.update_watchlist_artist_image(artist_id, image_url)
-                                    break
+                        else:
+                            itunes_url = f"https://itunes.apple.com/lookup?id={artist_id}&entity=album&limit=5"
+                            resp = requests.get(itunes_url, timeout=5)
+                            if resp.status_code == 200:
+                                results = resp.json().get('results', [])
+                                for res in results:
+                                    if 'artworkUrl100' in res:
+                                        image_url = res['artworkUrl100'].replace('100x100', '600x600')
+                                        database.update_watchlist_artist_image(artist_id, image_url)
+                                        break
                     elif spotify_client and spotify_client.is_authenticated():
                         artist_data = spotify_client.get_artist(artist_id)
                         if artist_data and 'images' in artist_data and artist_data['images']:
@@ -30368,11 +30394,14 @@ def watchlist_all_unwatched_library_artists():
                 continue
 
             # Check if already watched (shouldn't be since we filtered, but safety check)
-            if database.is_artist_in_watchlist(artist_id, profile_id=get_current_profile_id()):
+            if database.is_artist_in_watchlist(artist_id, profile_id=get_current_profile_id(), artist_name=artist_name):
                 skipped_already += 1
                 continue
 
-            success = database.add_artist_to_watchlist(artist_id, artist_name, profile_id=get_current_profile_id())
+            is_numeric = artist_id.isdigit()
+            fb_source = _get_metadata_fallback_source()
+            src = fb_source if is_numeric else 'spotify'
+            success = database.add_artist_to_watchlist(artist_id, artist_name, profile_id=get_current_profile_id(), source=src)
             if success:
                 added += 1
                 # Use library thumb_url if available (no HTTP calls needed)
@@ -30472,19 +30501,20 @@ def check_watchlist_status_batch():
 def start_watchlist_scan():
     """Start a watchlist scan for new releases"""
     try:
-        # Check if MetadataService can provide a working client (Spotify OR iTunes)
+        # Check if MetadataService can provide a working client (Spotify OR fallback)
         from core.metadata_service import MetadataService
         metadata_service = MetadataService()
-        
-        # Get active provider - will be either spotify or itunes
+
+        # Get active provider - will be spotify or the configured fallback
         active_provider = metadata_service.get_active_provider()
         provider_info = metadata_service.get_provider_info()
-        
+
         # Verify we have at least one working provider
         if not provider_info['spotify_authenticated'] and not provider_info['itunes_available']:
+            fallback_name = provider_info.get('fallback_source', 'iTunes').capitalize()
             return jsonify({
-                "success": False, 
-                "error": "No music provider available. Please authenticate Spotify or ensure iTunes is accessible."
+                "success": False,
+                "error": f"No music provider available. Please authenticate Spotify or ensure {fallback_name} is accessible."
             }), 400
         
         logger.info(f"Starting watchlist scan with {active_provider} provider")
@@ -31239,9 +31269,9 @@ def watchlist_artist_link_provider(artist_id):
             return jsonify({"success": False, "error": "No data provided"}), 400
 
         new_provider_id = data.get('provider_id', '').strip()
-        provider = data.get('provider', '').strip()  # 'spotify' or 'itunes'
+        provider = data.get('provider', '').strip()  # 'spotify', 'itunes', or 'deezer'
 
-        if not new_provider_id or provider not in ('spotify', 'itunes'):
+        if not new_provider_id or provider not in ('spotify', 'itunes', 'deezer'):
             return jsonify({"success": False, "error": "Missing provider or provider_id"}), 400
 
         conn = sqlite3.connect(str(database.database_path))
@@ -31251,8 +31281,8 @@ def watchlist_artist_link_provider(artist_id):
         cursor.execute("""
             SELECT id, artist_name, spotify_artist_id, itunes_artist_id
             FROM watchlist_artists
-            WHERE spotify_artist_id = ? OR itunes_artist_id = ?
-        """, (artist_id, artist_id))
+            WHERE spotify_artist_id = ? OR itunes_artist_id = ? OR deezer_artist_id = ?
+        """, (artist_id, artist_id, artist_id))
         row = cursor.fetchone()
 
         if not row:
@@ -31263,7 +31293,8 @@ def watchlist_artist_link_provider(artist_id):
         artist_name = row[1]
 
         # Check for duplicate — another watchlist artist already has this provider ID
-        col = 'spotify_artist_id' if provider == 'spotify' else 'itunes_artist_id'
+        col_map = {'spotify': 'spotify_artist_id', 'itunes': 'itunes_artist_id', 'deezer': 'deezer_artist_id'}
+        col = col_map[provider]
         cursor.execute(f"SELECT id, artist_name FROM watchlist_artists WHERE {col} = ? AND id != ?",
                        (new_provider_id, watchlist_row_id))
         duplicate = cursor.fetchone()
@@ -31271,12 +31302,8 @@ def watchlist_artist_link_provider(artist_id):
             conn.close()
             return jsonify({"success": False, "error": f"Another watchlist artist ('{duplicate[1]}') already has this {provider} ID"}), 409
 
-        if provider == 'spotify':
-            cursor.execute("UPDATE watchlist_artists SET spotify_artist_id = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?",
-                           (new_provider_id, watchlist_row_id))
-        else:
-            cursor.execute("UPDATE watchlist_artists SET itunes_artist_id = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?",
-                           (new_provider_id, watchlist_row_id))
+        cursor.execute(f"UPDATE watchlist_artists SET {col} = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?",
+                       (new_provider_id, watchlist_row_id))
 
         conn.commit()
         conn.close()
@@ -32057,11 +32084,11 @@ metadata_update_executor = ThreadPoolExecutor(max_workers=1, thread_name_prefix=
 def _get_active_discovery_source():
     """
     Determine which music source is active for discovery.
-    Returns 'spotify' if Spotify is authenticated, 'itunes' otherwise.
+    Returns 'spotify' if Spotify is authenticated, otherwise the configured fallback.
     """
     if spotify_client and spotify_client.is_spotify_authenticated():
         return 'spotify'
-    return 'itunes'
+    return _get_metadata_fallback_source()
 
 
 @app.route('/api/discover/hero', methods=['GET'])
@@ -32074,9 +32101,8 @@ def get_discover_hero():
         active_source = _get_active_discovery_source()
         print(f"🎵 Discover hero using source: {active_source}")
 
-        # Import iTunes client for fallback
-        from core.itunes_client import iTunesClient
-        itunes_client = iTunesClient()
+        # Import fallback client for non-Spotify lookups
+        itunes_client = _get_metadata_fallback_client()
 
         # Get top similar artists (excluding watchlist, cycled by last_featured)
         # Fetch more than needed since strict source filtering may drop many
@@ -32098,7 +32124,12 @@ def get_discover_hero():
 
             hero_artists = []
             for artist in shuffled_watchlist[:10]:
-                artist_id = artist.itunes_artist_id if active_source == 'itunes' else artist.spotify_artist_id
+                if active_source == 'spotify':
+                    artist_id = artist.spotify_artist_id
+                elif active_source == 'deezer':
+                    artist_id = getattr(artist, 'deezer_artist_id', None) or artist.itunes_artist_id
+                else:
+                    artist_id = artist.itunes_artist_id
                 if not artist_id:
                     continue
 
@@ -32127,35 +32158,41 @@ def get_discover_hero():
         for artist in similar_artists:
             if active_source == 'spotify' and artist.similar_artist_spotify_id:
                 valid_artists.append(artist)
+            elif active_source == 'deezer' and getattr(artist, 'similar_artist_deezer_id', None):
+                valid_artists.append(artist)
             elif active_source == 'itunes' and artist.similar_artist_itunes_id:
                 valid_artists.append(artist)
 
-        # FALLBACK: If no valid artists for iTunes, try to resolve iTunes IDs on-the-fly
-        if active_source == 'itunes' and not valid_artists:
-            print(f"[iTunes Fallback] No artists with iTunes IDs found, attempting on-the-fly resolution for {len(similar_artists)} artists")
+        # FALLBACK: If no valid artists for fallback source, try to resolve IDs on-the-fly
+        if active_source in ('itunes', 'deezer') and not valid_artists:
+            print(f"[{active_source} Fallback] No artists with {active_source} IDs found, attempting on-the-fly resolution for {len(similar_artists)} artists")
             resolved_count = 0
             for artist in similar_artists:
-                if artist.similar_artist_itunes_id:
+                existing_id = getattr(artist, f'similar_artist_{active_source}_id', None) or (artist.similar_artist_itunes_id if active_source == 'itunes' else None)
+                if existing_id:
                     valid_artists.append(artist)
                     continue
-                # Try to resolve iTunes ID by name
+                # Try to resolve ID by name
                 try:
-                    itunes_results = itunes_client.search_artists(artist.similar_artist_name, limit=1)
-                    if itunes_results and len(itunes_results) > 0:
-                        itunes_id = itunes_results[0].id
+                    search_results = itunes_client.search_artists(artist.similar_artist_name, limit=1)
+                    if search_results and len(search_results) > 0:
+                        resolved_id = search_results[0].id
                         # Cache the resolved ID for future use
-                        database.update_similar_artist_itunes_id(artist.id, itunes_id)
-                        # Create a modified artist object with the resolved ID
-                        artist.similar_artist_itunes_id = itunes_id
+                        if active_source == 'deezer':
+                            database.update_similar_artist_deezer_id(artist.id, resolved_id)
+                            artist.similar_artist_deezer_id = resolved_id
+                        else:
+                            database.update_similar_artist_itunes_id(artist.id, resolved_id)
+                            artist.similar_artist_itunes_id = resolved_id
                         valid_artists.append(artist)
                         resolved_count += 1
-                        print(f"  [Resolved] {artist.similar_artist_name} -> iTunes ID: {itunes_id}")
+                        print(f"  [Resolved] {artist.similar_artist_name} -> {active_source} ID: {resolved_id}")
                 except Exception as resolve_err:
-                    print(f"  [Failed] Could not resolve iTunes ID for {artist.similar_artist_name}: {resolve_err}")
+                    print(f"  [Failed] Could not resolve {active_source} ID for {artist.similar_artist_name}: {resolve_err}")
                 # Stop after 10 successful resolutions to avoid rate limiting
                 if len(valid_artists) >= 10:
                     break
-            print(f"[iTunes Fallback] Resolved {resolved_count} artists with iTunes IDs")
+            print(f"[{active_source} Fallback] Resolved {resolved_count} artists with IDs")
 
         print(f"[Discover Hero] Found {len(valid_artists)} valid artists for source: {active_source}")
 
@@ -32168,6 +32205,8 @@ def get_discover_hero():
             # Use the ID for the active source, falling back to the other if needed
             if active_source == 'spotify':
                 artist_id = artist.similar_artist_spotify_id or artist.similar_artist_itunes_id
+            elif active_source == 'deezer':
+                artist_id = getattr(artist, 'similar_artist_deezer_id', None) or artist.similar_artist_itunes_id or artist.similar_artist_spotify_id
             else:
                 artist_id = artist.similar_artist_itunes_id or artist.similar_artist_spotify_id
 
@@ -32202,18 +32241,21 @@ def get_discover_hero():
                                     artist.id, artist_data.get('image_url'),
                                     artist_data.get('genres'), artist_data.get('popularity')
                                 )
-                    elif active_source == 'itunes' and artist.similar_artist_itunes_id:
-                        itunes_artist = itunes_client.get_artist(artist.similar_artist_itunes_id)
-                        if itunes_artist:
-                            artist_data['artist_name'] = itunes_artist.get('name', artist.similar_artist_name)
-                            artist_data['image_url'] = itunes_artist.get('images', [{}])[0].get('url') if itunes_artist.get('images') else None
-                            artist_data['genres'] = itunes_artist.get('genres', [])
-                            artist_data['popularity'] = itunes_artist.get('popularity', 0)
-                            # Cache it
-                            database.update_similar_artist_metadata(
-                                artist.id, artist_data.get('image_url'),
-                                artist_data.get('genres'), artist_data.get('popularity')
-                            )
+                    elif active_source in ('itunes', 'deezer'):
+                        fb_artist_id = getattr(artist, 'similar_artist_deezer_id', None) if active_source == 'deezer' else None
+                        fb_artist_id = fb_artist_id or artist.similar_artist_itunes_id
+                        if fb_artist_id:
+                            fb_artist_data = itunes_client.get_artist(fb_artist_id)
+                            if fb_artist_data:
+                                artist_data['artist_name'] = fb_artist_data.get('name', artist.similar_artist_name)
+                                artist_data['image_url'] = fb_artist_data.get('images', [{}])[0].get('url') if fb_artist_data.get('images') else None
+                                artist_data['genres'] = fb_artist_data.get('genres', [])
+                                artist_data['popularity'] = fb_artist_data.get('popularity', 0)
+                                # Cache it
+                                database.update_similar_artist_metadata(
+                                    artist.id, artist_data.get('image_url'),
+                                    artist_data.get('genres'), artist_data.get('popularity')
+                                )
                 except Exception as img_err:
                     print(f"Could not fetch artist image: {img_err}")
 
@@ -32247,11 +32289,15 @@ def get_discover_similar_artists():
         for artist in similar_artists:
             if active_source == 'spotify' and not artist.similar_artist_spotify_id:
                 continue
+            if active_source == 'deezer' and not getattr(artist, 'similar_artist_deezer_id', None) and not artist.similar_artist_itunes_id:
+                continue
             if active_source == 'itunes' and not artist.similar_artist_itunes_id:
                 continue
 
             if active_source == 'spotify':
                 artist_id = artist.similar_artist_spotify_id
+            elif active_source == 'deezer':
+                artist_id = getattr(artist, 'similar_artist_deezer_id', None) or artist.similar_artist_itunes_id
             else:
                 artist_id = artist.similar_artist_itunes_id
 
@@ -32308,7 +32354,12 @@ def enrich_similar_artists():
         cached_artists = database.get_top_similar_artists(limit=500, profile_id=get_current_profile_id())
         cache_map = {}
         for artist in cached_artists:
-            ext_id = artist.similar_artist_spotify_id if source == 'spotify' else artist.similar_artist_itunes_id
+            if source == 'spotify':
+                ext_id = artist.similar_artist_spotify_id
+            elif source == 'deezer':
+                ext_id = getattr(artist, 'similar_artist_deezer_id', None) or artist.similar_artist_itunes_id
+            else:
+                ext_id = artist.similar_artist_itunes_id
             if ext_id and ext_id not in cache_map:
                 cache_map[ext_id] = artist
 
@@ -32352,23 +32403,23 @@ def enrich_similar_artists():
                     _detect_and_set_rate_limit(e, 'enrich_similar_artists')
                     print(f"Error enriching Spotify batch: {e}")
             else:
-                from core.itunes_client import iTunesClient
-                itunes_client = iTunesClient()
+                fallback_client = _get_metadata_fallback_client()
+                fallback_source = _get_metadata_fallback_source()
                 for aid in uncached_ids[:50]:
                     try:
-                        itunes_artist = itunes_client.get_artist(aid)
-                        if itunes_artist:
-                            img_url = itunes_artist.get('images', [{}])[0].get('url') if itunes_artist.get('images') else None
-                            genres = itunes_artist.get('genres', [])[:3]
+                        fb_artist = fallback_client.get_artist(aid)
+                        if fb_artist:
+                            img_url = fb_artist.get('images', [{}])[0].get('url') if fb_artist.get('images') else None
+                            genres = fb_artist.get('genres', [])[:3]
                             enriched[aid] = {
-                                "artist_name": itunes_artist.get('name'),
+                                "artist_name": fb_artist.get('name'),
                                 "image_url": img_url,
                                 "genres": genres,
                                 "popularity": 0
                             }
                             # Cache to DB for future use
                             database.update_similar_artist_metadata_by_external_id(
-                                aid, 'itunes',
+                                aid, fallback_source,
                                 image_url=img_url, genres=genres, popularity=0
                             )
                     except Exception:
@@ -32533,6 +32584,8 @@ def get_discover_release_radar():
             for track in discovery_tracks:
                 if active_source == 'spotify' and track.spotify_track_id:
                     tracks_by_id[track.spotify_track_id] = track
+                elif active_source == 'deezer' and getattr(track, 'deezer_track_id', None):
+                    tracks_by_id[track.deezer_track_id] = track
                 elif active_source == 'itunes' and track.itunes_track_id:
                     tracks_by_id[track.itunes_track_id] = track
 
@@ -32550,9 +32603,10 @@ def get_discover_release_radar():
                             track_data = None
 
                     selected_tracks.append({
-                        "track_id": track.spotify_track_id or track.itunes_track_id,
+                        "track_id": track.spotify_track_id or getattr(track, 'deezer_track_id', None) or track.itunes_track_id,
                         "spotify_track_id": track.spotify_track_id,
                         "itunes_track_id": track.itunes_track_id,
+                        "deezer_track_id": getattr(track, 'deezer_track_id', None),
                         "track_name": track.track_name,
                         "artist_name": track.artist_name,
                         "album_name": track.album_name,
@@ -32597,6 +32651,8 @@ def get_discover_weekly():
             for track in discovery_tracks:
                 if active_source == 'spotify' and track.spotify_track_id:
                     tracks_by_id[track.spotify_track_id] = track
+                elif active_source == 'deezer' and getattr(track, 'deezer_track_id', None):
+                    tracks_by_id[track.deezer_track_id] = track
                 elif active_source == 'itunes' and track.itunes_track_id:
                     tracks_by_id[track.itunes_track_id] = track
 
@@ -32614,9 +32670,10 @@ def get_discover_weekly():
                             track_data = None
 
                     selected_tracks.append({
-                        "track_id": track.spotify_track_id or track.itunes_track_id,
+                        "track_id": track.spotify_track_id or getattr(track, 'deezer_track_id', None) or track.itunes_track_id,
                         "spotify_track_id": track.spotify_track_id,
                         "itunes_track_id": track.itunes_track_id,
+                        "deezer_track_id": getattr(track, 'deezer_track_id', None),
                         "track_name": track.track_name,
                         "artist_name": track.artist_name,
                         "album_name": track.album_name,
@@ -33186,14 +33243,13 @@ def search_artists_for_playlist():
                     logger.warning(f"Spotify artist search failed, falling back to iTunes: {e}")
 
             if not artists:
-                from core.itunes_client import iTunesClient
-                itunes = iTunesClient()
-                artist_objs = itunes.search_artists(query, limit=10)
+                fallback = _get_metadata_fallback_client()
+                artist_objs = fallback.search_artists(query, limit=10)
                 for artist in artist_objs:
-                    # iTunes artist search rarely returns images — grab from album art
+                    # Fallback artist search may not return images — grab from album art
                     image = artist.image_url
                     if not image:
-                        image = itunes._get_artist_image_from_albums(artist.id)
+                        image = fallback._get_artist_image_from_albums(artist.id)
                     artists.append({
                         'id': artist.id,
                         'name': artist.name,
@@ -35821,13 +35877,12 @@ def _run_beatport_discovery_worker(url_hash):
 
         # Determine which provider to use
         use_spotify = spotify_client and spotify_client.is_spotify_authenticated()
-        discovery_source = 'spotify' if use_spotify else 'itunes'
+        discovery_source = 'spotify' if use_spotify else _get_metadata_fallback_source()
 
-        # Initialize iTunes client if needed
+        # Initialize fallback client if needed
         itunes_client_instance = None
         if not use_spotify:
-            from core.itunes_client import iTunesClient
-            itunes_client_instance = iTunesClient()
+            itunes_client_instance = _get_metadata_fallback_client()
 
         print(f"🔍 Starting {discovery_source.upper()} discovery for {len(tracks)} Beatport tracks...")
 
@@ -36051,7 +36106,7 @@ def _run_beatport_discovery_worker(url_hash):
                             'artists': formatted_artists,
                             'album': album_data,
                             'id': track_id,
-                            'source': 'itunes'
+                            'source': discovery_source
                         }
 
                     state['spotify_matches'] += 1

webui/index.html

@@ -3626,6 +3626,21 @@
                                     </div>
                                 </div>
 
+                                <!-- Metadata Source Selection -->
+                                <div class="api-service-frame">
+                                    <h4 class="service-title" style="color: #e8e8e8;">Metadata Source</h4>
+                                    <div class="form-group">
+                                        <label>Fallback Source:</label>
+                                        <select id="metadata-fallback-source">
+                                            <option value="itunes">iTunes / Apple Music</option>
+                                            <option value="deezer">Deezer</option>
+                                        </select>
+                                    </div>
+                                    <div class="callback-info">
+                                        <div class="callback-help">When Spotify is not connected, this source provides artist, album, and track metadata. Both are free and require no API key.</div>
+                                    </div>
+                                </div>
+
                                 <!-- Test Connection Buttons -->
                                 <div class="api-test-buttons">
                                     <button class="test-button" onclick="testConnection('spotify')">Test
@@ -5644,6 +5659,10 @@
                     <span class="mcache-stat-pill-label">iTunes</span>
                     <span class="mcache-stat-pill-value" id="mcache-browse-itunes-count">0</span>
                 </div>
+                <div class="mcache-stat-pill">
+                    <span class="mcache-stat-pill-label">Deezer</span>
+                    <span class="mcache-stat-pill-value" id="mcache-browse-deezer-count">0</span>
+                </div>
                 <div class="mcache-stat-pill">
                     <span class="mcache-stat-pill-label">Total Hits</span>
                     <span class="mcache-stat-pill-value" id="mcache-browse-hits">0</span>
@@ -5664,6 +5683,7 @@
                     <option value="">All Sources</option>
                     <option value="spotify">Spotify</option>
                     <option value="itunes">iTunes</option>
+                    <option value="deezer">Deezer</option>
                 </select>
                 <select class="mcache-sort-filter" id="mcache-sort-filter" onchange="loadMetadataCacheBrowse()">
                     <option value="last_accessed_at">Recently Accessed</option>
@@ -5836,7 +5856,7 @@
                 <button class="modal-button modal-button--secondary" onclick="closeRateLimitModal()">Dismiss</button>
                 <button class="modal-button rate-limit-disconnect-btn" onclick="disconnectSpotifyFromRateLimit()">
                     Disconnect Spotify
-                    <span class="rate-limit-disconnect-sub">Clear ban, pause enrichment &amp; switch to iTunes</span>
+                    <span class="rate-limit-disconnect-sub">Clear ban, pause enrichment &amp; switch to fallback source</span>
                 </button>
             </div>
         </div>

webui/static/script.js

@@ -4805,6 +4805,9 @@ async function loadSettingsData() {
         // Populate iTunes settings
         document.getElementById('itunes-country').value = settings.itunes?.country || 'US';
 
+        // Populate Metadata source setting
+        document.getElementById('metadata-fallback-source').value = settings.metadata?.fallback_source || 'itunes';
+
         // Populate Download settings (right column)
         document.getElementById('download-path').value = settings.soulseek?.download_path || './downloads';
         document.getElementById('transfer-path').value = settings.soulseek?.transfer_path || './Transfer';
@@ -5644,6 +5647,9 @@ async function saveSettings(quiet = false) {
         itunes: {
             country: document.getElementById('itunes-country').value || 'US'
         },
+        metadata: {
+            fallback_source: document.getElementById('metadata-fallback-source').value || 'itunes'
+        },
         download_source: {
             mode: document.getElementById('download-source-mode').value,
             hybrid_primary: document.getElementById('hybrid-primary-source').value,
@@ -5760,13 +5766,13 @@ async function saveSettings(quiet = false) {
 
         if (result.success && qualityProfileSaved && lookbackSaved) {
             showToast(quiet ? 'Settings auto-saved' : 'Settings saved successfully', 'success');
-            setTimeout(updateServiceStatus, 1000);
+            _forceServiceStatusRefresh();
         } else if (result.success && qualityProfileSaved && !lookbackSaved) {
             showToast('Settings saved, but discovery lookback period failed to save', 'warning');
-            setTimeout(updateServiceStatus, 1000);
+            _forceServiceStatusRefresh();
         } else if (result.success && !qualityProfileSaved) {
             showToast('Settings saved, but quality profile failed to save', 'warning');
-            setTimeout(updateServiceStatus, 1000);
+            _forceServiceStatusRefresh();
         } else {
             showToast(`Failed to save settings: ${result.error}`, 'error', 'set-services');
         }
@@ -6114,7 +6120,8 @@ async function authenticateSpotify() {
 }
 
 async function disconnectSpotify() {
-    if (!await showConfirmDialog({ title: 'Disconnect Spotify', message: 'Disconnect Spotify? The app will switch to Apple Music/iTunes for metadata.' })) {
+    const fallbackName = currentMusicSourceName !== 'Spotify' ? currentMusicSourceName : 'the configured fallback source';
+    if (!await showConfirmDialog({ title: 'Disconnect Spotify', message: `Disconnect Spotify? The app will switch to ${fallbackName} for metadata.` })) {
         return;
     }
     try {
@@ -6122,7 +6129,7 @@ async function disconnectSpotify() {
         const response = await fetch('/api/spotify/disconnect', { method: 'POST' });
         const data = await response.json();
         if (data.success) {
-            showToast('Spotify disconnected. Now using Apple Music/iTunes.', 'success');
+            showToast(`Spotify disconnected. Now using ${fallbackName}.`, 'success');
             // Immediately refresh status to update UI
             await fetchAndUpdateServiceStatus();
         } else {
@@ -6222,7 +6229,7 @@ async function disconnectSpotifyFromRateLimit() {
         const data = await response.json();
         if (data.success) {
             _spotifyRateLimitShown = false;
-            showToast('Spotify disconnected. Now using Apple Music/iTunes.', 'success');
+            showToast(`Spotify disconnected. Now using ${currentMusicSourceName}.`, 'success');
             await fetchAndUpdateServiceStatus();
             if (currentPage === 'discover') {
                 loadDiscoverPage();
@@ -15234,10 +15241,10 @@ async function searchDiscoveryFix() {
     const identifier = currentDiscoveryFix.identifier;
     const state = listenbrainzPlaylistStates[identifier] || youtubePlaylistStates[identifier];
     const discoverySource = state?.discovery_source || state?.discoverySource || 'spotify';
-    const useItunes = discoverySource === 'itunes';
+    const useFallback = discoverySource !== 'spotify';
 
     const resultsContainer = fixModalOverlay.querySelector('#fix-modal-results');
-    const sourceLabel = useItunes ? 'iTunes' : 'Spotify';
+    const sourceLabel = discoverySource === 'spotify' ? 'Spotify' : discoverySource === 'deezer' ? 'Deezer' : 'iTunes';
     resultsContainer.innerHTML = `<div class="loading">🔍 Searching ${sourceLabel}...</div>`;
 
     try {
@@ -15245,7 +15252,7 @@ async function searchDiscoveryFix() {
         const query = `${artistInput} ${trackInput}`.trim();
 
         // Call appropriate search API based on discovery source
-        const searchEndpoint = useItunes ? '/api/itunes/search_tracks' : '/api/spotify/search_tracks';
+        const searchEndpoint = useFallback ? '/api/itunes/search_tracks' : '/api/spotify/search_tracks';
         const response = await fetch(`${searchEndpoint}?query=${encodeURIComponent(query)}&limit=20`);
         const data = await response.json();
 
@@ -18026,9 +18033,9 @@ async function loadMetadataCacheStats() {
         const tracksEl = document.getElementById('mcache-stat-tracks');
         const hitsEl = document.getElementById('mcache-stat-hits');
 
-        if (artistsEl) artistsEl.textContent = (stats.artists?.spotify || 0) + (stats.artists?.itunes || 0);
-        if (albumsEl) albumsEl.textContent = (stats.albums?.spotify || 0) + (stats.albums?.itunes || 0);
-        if (tracksEl) tracksEl.textContent = (stats.tracks?.spotify || 0) + (stats.tracks?.itunes || 0);
+        if (artistsEl) artistsEl.textContent = (stats.artists?.spotify || 0) + (stats.artists?.itunes || 0) + (stats.artists?.deezer || 0);
+        if (albumsEl) albumsEl.textContent = (stats.albums?.spotify || 0) + (stats.albums?.itunes || 0) + (stats.albums?.deezer || 0);
+        if (tracksEl) tracksEl.textContent = (stats.tracks?.spotify || 0) + (stats.tracks?.itunes || 0) + (stats.tracks?.deezer || 0);
         if (hitsEl) hitsEl.textContent = stats.total_hits || 0;
     } catch (e) {
         // Silently fail — cache may not be initialized yet
@@ -18203,8 +18210,10 @@ async function loadMetadataCacheBrowseStats() {
 
         const spotifyTotal = (stats.artists?.spotify || 0) + (stats.albums?.spotify || 0) + (stats.tracks?.spotify || 0);
         const itunesTotal = (stats.artists?.itunes || 0) + (stats.albums?.itunes || 0) + (stats.tracks?.itunes || 0);
+        const deezerTotal = (stats.artists?.deezer || 0) + (stats.albums?.deezer || 0) + (stats.tracks?.deezer || 0);
         el('mcache-browse-spotify-count', spotifyTotal);
         el('mcache-browse-itunes-count', itunesTotal);
+        el('mcache-browse-deezer-count', deezerTotal);
         el('mcache-browse-hits', stats.total_hits || 0);
         el('mcache-browse-searches', stats.searches || 0);
     } catch (e) { /* ignore */ }
@@ -33627,6 +33636,18 @@ function escapeHtml(text) {
 
 // --- Service Status and System Stats Functions ---
 
+async function _forceServiceStatusRefresh() {
+    // Force an immediate status refresh (bypasses WebSocket check) — used after settings save
+    try {
+        const response = await fetch('/status');
+        if (!response.ok) return;
+        const data = await response.json();
+        handleServiceStatusUpdate(data);
+    } catch (error) {
+        console.warn('Could not force service status refresh:', error);
+    }
+}
+
 async function fetchAndUpdateServiceStatus() {
     if (document.hidden) return; // Skip polling when tab is not visible
     if (socketConnected) return; // WebSocket is pushing updates — skip HTTP poll
@@ -33669,7 +33690,8 @@ function updateServiceStatus(service, statusData) {
                 ? formatRateLimitDuration(statusData.rate_limit?.remaining_seconds || 0)
                 : formatRateLimitDuration(statusData.post_ban_cooldown);
             const phase = statusData.rate_limited ? 'paused' : 'recovering';
-            statusText.textContent = `Apple Music (Spotify ${phase} \u2014 ${remaining})`;
+            const fallbackLabel = statusData.source === 'deezer' ? 'Deezer' : 'Apple Music';
+            statusText.textContent = `${fallbackLabel} (Spotify ${phase} \u2014 ${remaining})`;
             statusText.className = 'service-card-status-text rate-limited';
         } else if (statusData.connected) {
             indicator.className = 'service-card-indicator connected';
@@ -33686,7 +33708,7 @@ function updateServiceStatus(service, statusData) {
     if (service === 'spotify' && statusData.source) {
         const musicSourceTitleElement = document.getElementById('music-source-title');
         if (musicSourceTitleElement) {
-            const sourceName = statusData.source === 'itunes' ? 'Apple Music' : 'Spotify';
+            const sourceName = statusData.source === 'spotify' ? 'Spotify' : statusData.source === 'deezer' ? 'Deezer' : 'Apple Music';
             musicSourceTitleElement.textContent = sourceName;
             // Update global variable for use in discovery modals
             currentMusicSourceName = sourceName;
@@ -33742,7 +33764,7 @@ function updateSidebarServiceStatus(service, statusData) {
         if (service === 'spotify' && statusData.source) {
             const musicSourceNameElement = document.getElementById('music-source-name');
             if (musicSourceNameElement) {
-                const sourceName = statusData.source === 'itunes' ? 'Apple Music' : 'Spotify';
+                const sourceName = statusData.source === 'spotify' ? 'Spotify' : statusData.source === 'deezer' ? 'Deezer' : 'Apple Music';
                 musicSourceNameElement.textContent = sourceName;
             }
         }
@@ -45423,7 +45445,7 @@ async function openRecommendedArtistsModal() {
         // Phase 2: Enrich with images/genres progressively in batches of 50
         // Skip artists that already have cached metadata from the initial response
         const source = data.source || 'spotify';
-        const idKey = source === 'spotify' ? 'spotify_artist_id' : 'itunes_artist_id';
+        const idKey = source === 'spotify' ? 'spotify_artist_id' : source === 'deezer' ? 'deezer_artist_id' : 'itunes_artist_id';
         const allIds = data.artists
             .filter(a => !a.image_url)  // Only enrich artists without cached images
             .map(a => a[idKey]).filter(Boolean);
@@ -49382,8 +49404,8 @@ async function openDownloadModalForRecentAlbum(albumIndex) {
 
     try {
         // Determine source and album ID - use source-agnostic endpoint
-        const source = album.source || (album.album_spotify_id ? 'spotify' : 'itunes');
-        const albumId = source === 'spotify' ? album.album_spotify_id : album.album_itunes_id;
+        const source = album.source || (album.album_spotify_id ? 'spotify' : album.album_deezer_id ? 'deezer' : 'itunes');
+        const albumId = source === 'spotify' ? album.album_spotify_id : source === 'deezer' ? album.album_deezer_id : album.album_itunes_id;
 
         if (!albumId) {
             throw new Error(`No ${source} album ID available`);
@@ -49431,7 +49453,7 @@ async function openDownloadModalForRecentAlbum(albumIndex) {
 
         // CRITICAL FIX: Pass proper artist/album context for modal display
         const artistContext = {
-            id: source === 'spotify' ? album.artist_spotify_id : album.artist_itunes_id,
+            id: source === 'spotify' ? album.artist_spotify_id : source === 'deezer' ? album.artist_deezer_id : album.artist_itunes_id,
             name: album.artist_name,
             source: source
         };