Subsonic: browsing endpoints (getMusicFolders, getIndexes, getMusicDirectory, getGenres, getArtists/Artist, getAlbum, getSong, getVideos/VideoInfo, getArtistInfo/2, getAlbumInfo/2, getSimilarSongs/2, getTopSongs)

internal/database/subsonic_helpers2.go

@@ -0,0 +1,91 @@
+package database
+
+import "database/sql"
+
+// ListVideoMediaFiles returns every media file the scanner identified as
+// a video (as opposed to audio) track.
+func ListVideoMediaFiles(db *sql.DB) ([]*MediaFile, error) {
+	rows, err := db.Query(mediaFileSelect + ` WHERE kind = 'video' AND missing = 0 ORDER BY relative_path`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	return scanMediaFiles(rows)
+}
+
+// FindArtistByName looks up an artist by exact, case-insensitive name —
+// used by endpoints that take an artist name rather than ID (getTopSongs).
+func FindArtistByName(db *sql.DB, name string) (*Artist, error) {
+	var id string
+	err := db.QueryRow(`SELECT id FROM artists WHERE name = ? COLLATE NOCASE LIMIT 1`, name).Scan(&id)
+	if err == sql.ErrNoRows {
+		return nil, ErrNotFound
+	}
+	if err != nil {
+		return nil, err
+	}
+	return GetArtist(db, id)
+}
+
+// TopSongsByArtist returns an artist's songs ordered by total play count
+// (across all users) descending, falling back to any order for songs
+// that have never been played, up to limit.
+func TopSongsByArtist(db *sql.DB, artistID string, limit int) ([]*Song, error) {
+	rows, err := db.Query(`SELECT s.id, s.media_file_id, s.album_id, s.title, s.sort_title, s.track_number, s.track_total, s.disc_number, s.disc_total,
+		s.composer, s.conductor, s.isrc, s.bpm, s.musicbrainz_track_id, s.musicbrainz_recording_id,
+		s.replaygain_track_gain_db, s.replaygain_track_peak, s.replaygain_album_gain_db, s.replaygain_album_peak
+		FROM songs s
+		JOIN song_artists sa ON sa.song_id = s.id
+		LEFT JOIN (SELECT song_id, COUNT(*) AS plays FROM playback_history GROUP BY song_id) ph ON ph.song_id = s.id
+		WHERE sa.artist_id = ?
+		GROUP BY s.id
+		ORDER BY COALESCE(MAX(ph.plays), 0) DESC, s.title COLLATE NOCASE
+		LIMIT ?`, artistID, limit)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	return scanSongs(rows)
+}
+
+// SimilarSongsByGenre returns up to limit random songs sharing at least
+// one genre with seedSongID, excluding the seed itself. A simple,
+// honest local substitute for an external recommendation service.
+func SimilarSongsByGenre(db *sql.DB, seedSongID string, limit int) ([]*Song, error) {
+	rows, err := db.Query(`SELECT DISTINCT s.id, s.media_file_id, s.album_id, s.title, s.sort_title, s.track_number, s.track_total, s.disc_number, s.disc_total,
+		s.composer, s.conductor, s.isrc, s.bpm, s.musicbrainz_track_id, s.musicbrainz_recording_id,
+		s.replaygain_track_gain_db, s.replaygain_track_peak, s.replaygain_album_gain_db, s.replaygain_album_peak
+		FROM songs s
+		JOIN song_genres sg ON sg.song_id = s.id
+		WHERE sg.genre_id IN (SELECT genre_id FROM song_genres WHERE song_id = ?)
+		AND s.id != ?
+		ORDER BY RANDOM() LIMIT ?`, seedSongID, seedSongID, limit)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	return scanSongs(rows)
+}
+
+// SimilarSongsByArtist returns up to limit random songs by the given
+// artist (or sharing a genre with them if that artist has few songs),
+// excluding none in particular — used for getSimilarSongs2's artist
+// seed.
+func SimilarSongsByArtist(db *sql.DB, artistID string, limit int) ([]*Song, error) {
+	rows, err := db.Query(`SELECT DISTINCT s.id, s.media_file_id, s.album_id, s.title, s.sort_title, s.track_number, s.track_total, s.disc_number, s.disc_total,
+		s.composer, s.conductor, s.isrc, s.bpm, s.musicbrainz_track_id, s.musicbrainz_recording_id,
+		s.replaygain_track_gain_db, s.replaygain_track_peak, s.replaygain_album_gain_db, s.replaygain_album_peak
+		FROM songs s
+		JOIN song_genres sg ON sg.song_id = s.id
+		WHERE sg.genre_id IN (
+			SELECT DISTINCT sg2.genre_id FROM song_artists sa2
+			JOIN song_genres sg2 ON sg2.song_id = sa2.song_id
+			WHERE sa2.artist_id = ?
+		)
+		ORDER BY RANDOM() LIMIT ?`, artistID, limit)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	return scanSongs(rows)
+}