The mirror_playlist fix only assigns stable ids to newly-imported playlists, so a
user with an existing file-import playlist would still have empty-id rows (and dead
Find & Add matches) until a manual re-import. Add an idempotent startup backfill that
assigns the SAME stable id a fresh import would to any mirrored track missing one —
so existing matches start sticking with no re-import. Runs once per db/process (the
init is guarded), only touches empty-id rows (no-op afterward), native ids untouched.
Tests: backfill fills empty ids with the exact fresh-import id, is idempotent (2nd
run = 0), and leaves native ids alone.
A Find & Add on a file-import (CSV/M3U/TXT) playlist track was silently dropped and
the track re-appeared as 'extra' (radoslav-orlov). Root cause: unlike Spotify/YouTube
(native ids), file-import + iTunes-only tracks arrive with an EMPTY source_track_id —
and the whole manual-match system keys on it. _persist_find_and_add_match is a no-op
on an empty id, and find_manual_library_match_by_source_track_id returns None for one,
so the match can be neither recorded nor looked up. That's the youtube-vs-file
difference the reporter noticed.
Fix: stable_source_track_id() derives a DETERMINISTIC 'file:<hash>' id from the track
identity (artist|title|album, normalized) when there's no native id; mirror_playlist
assigns it so the SAME song gets the SAME id across re-imports/discovery — exactly
what the match lookup needs. Native ids are used verbatim; bonus: discovery extra_data
now survives a re-import for these tracks too.
Tests: helper (native passthrough, deterministic + case/field-insensitive, distinct
per song, empty-on-no-title, file: prefix); mirror_playlist integration (file tracks
get stable distinct ids, stable across re-import, native ids untouched). 319 playlist/
sync/discovery/mirrored tests green.
Centralize mirrored playlist source reference normalization so edited links and IDs are stored consistently. Preserve URL-backed refresh refs, surface missing-source refresh failures, count background sync failures in pipeline summaries, and retry guarded automation skips after a short delay instead of losing a scheduled run. Add focused coverage for source refs, mirrored playlist source updates, refresh failures, and guarded retry behavior.
