-- v0.12.4: Performance & Scalabilité — Critical indexes for query optimization
-- Reference: ORIGIN_PERFORMANCE_TARGETS.md §8.4

-- ============================================================================
-- USERS — Frequently queried by email, username, creation date
-- ============================================================================
CREATE INDEX IF NOT EXISTS idx_users_email ON users(email);
CREATE INDEX IF NOT EXISTS idx_users_username ON users(username);
CREATE INDEX IF NOT EXISTS idx_users_created_at ON users(created_at DESC);

-- ============================================================================
-- TRACKS — Core entity, heavy read traffic
-- ============================================================================
CREATE INDEX IF NOT EXISTS idx_tracks_creator_id ON tracks(creator_id);
CREATE INDEX IF NOT EXISTS idx_tracks_genre ON tracks(genre);
CREATE INDEX IF NOT EXISTS idx_tracks_created_at ON tracks(created_at DESC);
CREATE INDEX IF NOT EXISTS idx_tracks_status_created ON tracks(status, created_at DESC)
    WHERE deleted_at IS NULL;

-- ============================================================================
-- MESSAGES — Chat performance (room+time range queries)
-- ============================================================================
CREATE INDEX IF NOT EXISTS idx_messages_room_created ON messages(room_id, created_at DESC);
CREATE INDEX IF NOT EXISTS idx_messages_sender_id ON messages(sender_id);

-- ============================================================================
-- PLAYLISTS — Discovery and user playlists
-- ============================================================================
CREATE INDEX IF NOT EXISTS idx_playlists_creator_id ON playlists(creator_id);
CREATE INDEX IF NOT EXISTS idx_playlists_public_created ON playlists(is_public, created_at DESC)
    WHERE deleted_at IS NULL;

-- ============================================================================
-- PLAYLIST TRACKS — Join table, ordering
-- ============================================================================
CREATE INDEX IF NOT EXISTS idx_playlist_tracks_playlist ON playlist_tracks(playlist_id, position);
CREATE INDEX IF NOT EXISTS idx_playlist_tracks_track ON playlist_tracks(track_id);

-- ============================================================================
-- FEED / SOCIAL — Follows, feed generation
-- ============================================================================
CREATE INDEX IF NOT EXISTS idx_follows_follower ON follows(follower_id);
CREATE INDEX IF NOT EXISTS idx_follows_following ON follows(following_id);

-- ============================================================================
-- COMMENTS — Track comments and replies
-- ============================================================================
CREATE INDEX IF NOT EXISTS idx_comments_track_created ON comments(track_id, created_at DESC)
    WHERE deleted_at IS NULL;
CREATE INDEX IF NOT EXISTS idx_comments_user ON comments(user_id);

-- ============================================================================
-- NOTIFICATIONS — User notification inbox
-- ============================================================================
CREATE INDEX IF NOT EXISTS idx_notifications_user_created ON notifications(user_id, created_at DESC);
CREATE INDEX IF NOT EXISTS idx_notifications_user_unread ON notifications(user_id, is_read)
    WHERE is_read = false;

-- ============================================================================
-- ANALYTICS — Creator dashboard queries
-- ============================================================================
CREATE INDEX IF NOT EXISTS idx_track_plays_track_date ON track_plays(track_id, played_at DESC);
CREATE INDEX IF NOT EXISTS idx_track_plays_user ON track_plays(user_id, played_at DESC);

-- ============================================================================
-- MARKETPLACE — Transactions and listings
-- ============================================================================
CREATE INDEX IF NOT EXISTS idx_marketplace_listings_status ON marketplace_listings(status, created_at DESC)
    WHERE deleted_at IS NULL;
CREATE INDEX IF NOT EXISTS idx_marketplace_transactions_buyer ON marketplace_transactions(buyer_id, created_at DESC);
CREATE INDEX IF NOT EXISTS idx_marketplace_transactions_seller ON marketplace_transactions(seller_id, created_at DESC);

-- ============================================================================
-- EDUCATION — Course discovery and enrollment
-- ============================================================================
CREATE INDEX IF NOT EXISTS idx_courses_status_created ON courses(status, created_at DESC)
    WHERE deleted_at IS NULL;
CREATE INDEX IF NOT EXISTS idx_course_enrollments_user ON course_enrollments(user_id, created_at DESC);

-- ============================================================================
-- FULL-TEXT SEARCH (GIN indexes for PostgreSQL text search)
-- ============================================================================
CREATE INDEX IF NOT EXISTS idx_tracks_search_gin ON tracks
    USING GIN(to_tsvector('english', COALESCE(title, '') || ' ' || COALESCE(description, '')));
CREATE INDEX IF NOT EXISTS idx_users_search_gin ON users
    USING GIN(to_tsvector('english', COALESCE(username, '') || ' ' || COALESCE(display_name, '')));

-- ============================================================================
-- STATISTICS — Update planner statistics for optimal query plans
-- ============================================================================
ANALYZE users;
ANALYZE tracks;
ANALYZE messages;
ANALYZE playlists;
ANALYZE follows;
ANALYZE notifications;
