-- 048_search_indexes.sql
-- Search Indexes (BE-DB-009: Add indexes for search queries)
-- Add full-text search indexes on tracks.title, tracks.artist, users.username

-- === TRACKS SEARCH INDEXES ===
-- Index for searching by title (case-insensitive)
CREATE INDEX IF NOT EXISTS idx_tracks_title_gin ON public.tracks USING GIN(to_tsvector('english', title));

-- Index for searching by artist (case-insensitive)
CREATE INDEX IF NOT EXISTS idx_tracks_artist_gin ON public.tracks USING GIN(to_tsvector('english', COALESCE(artist, '')));

-- B-tree indexes for exact matches and prefix searches
CREATE INDEX IF NOT EXISTS idx_tracks_title_btree ON public.tracks(title) WHERE deleted_at IS NULL;
CREATE INDEX IF NOT EXISTS idx_tracks_artist_btree ON public.tracks(artist) WHERE deleted_at IS NULL AND artist IS NOT NULL;

-- === USERS SEARCH INDEXES ===
-- Index for searching by username (case-insensitive)
-- Note: idx_users_username already exists as UNIQUE index, but we add a GIN index for full-text search
CREATE INDEX IF NOT EXISTS idx_users_username_gin ON public.users USING GIN(to_tsvector('english', username)) WHERE deleted_at IS NULL;

-- B-tree index for prefix searches on username (if not already covered by unique index)
-- The unique index idx_users_username already exists, but we add a separate index for LIKE queries
CREATE INDEX IF NOT EXISTS idx_users_username_lower ON public.users(LOWER(username)) WHERE deleted_at IS NULL;

-- Comments
COMMENT ON INDEX idx_tracks_title_gin IS 'Full-text search index on track titles';
COMMENT ON INDEX idx_tracks_artist_gin IS 'Full-text search index on track artists';
COMMENT ON INDEX idx_tracks_title_btree IS 'B-tree index for exact and prefix searches on track titles';
COMMENT ON INDEX idx_tracks_artist_btree IS 'B-tree index for exact and prefix searches on track artists';
COMMENT ON INDEX idx_users_username_gin IS 'Full-text search index on usernames';
COMMENT ON INDEX idx_users_username_lower IS 'Case-insensitive index for username prefix searches';