Create SearchIndex in NewExploreService, start background build in
SetContext (on app startup). Search() now has 6 phases:
Phase 0: query local FTS5 index (instant, no API calls)
Phase 1: concurrent MB search
Phase 2: LB popularity boost
Phase 3: cross-reference artist discographies
Phase 4: merge index hits (prepend new entries, dedup by MBID)
Phase 5: filter and cap
Index hits for release groups/recordings not already in MB results
are prepended so popular albums surface even when MB search can't
find them. scalePopularity() maps raw listen counts to 0-100 scores
via log scaling for compatibility with the blended score system.
After MB search + popularity reranking, browse the discographies of
the top 3 artists and fuzzy-match the full query against album titles.
Matching albums not already in results are injected at the front.
Fuzzy matching uses substring containment with word-level ratio
(handles 'for you tatsuro' → 'FOR YOU' at 0.667) and word overlap
as fallback. Threshold: 0.4 ratio.
Example: 'for you tatsuro' now finds FOR YOU by 山下達郎 even though
MB text search treats 'for' and 'you' as stop words and never
returns it. The album is found via Yamashita's cached discography.
Drop artists and recordings with blended score < 25 after popularity
reranking. Cap each entity slice to 15 server-side. Request 20 from
MB to allow filtering headroom. Reduces payload size and noise.
After MB search returns text-relevance-scored results, fetch bulk
popularity data from ListenBrainz (POST /1/popularity/{artist,
recording,release-group}) for all result MBIDs. Blend scores:
final = 0.6 * mb_relevance + 0.4 * log10_popularity
Log-scale normalization ensures massive artists don't drown out
everything, but popular results rise above obscure exact matches.
Release groups (no MB score) sort by raw popularity.
Three LB POST calls run concurrently — each hits a different
endpoint. All are rate-limited and cached (24h TTL).
Example: searching 'tatsuro' now ranks Tatsuro Yamashita (2.5M LB
listens, score 97) above 'tatsuro' vocaloid producer (4 listens,
score 64) despite the latter being an exact name match on MB.
yonlu