Use LB API to lookup missing metadata for loves

This is faster than using the MBID API individually

internal/backends/listenbrainz/helper.go

@@ -32,35 +32,6 @@ import (
 	"go.uploadedlobster.com/scotty/internal/models"
 )
 
-func LookupRecording(
-	ctx context.Context,
-	mb *musicbrainzws2.Client,
-	mbid mbtypes.MBID,
-) (*listenbrainz.Track, error) {
-	filter := musicbrainzws2.IncludesFilter{
-		Includes: []string{"artist-credits"},
-	}
-	recording, err := mb.LookupRecording(ctx, mbid, filter)
-	if err != nil {
-		return nil, err
-	}
-
-	artistMBIDs := make([]mbtypes.MBID, 0, len(recording.ArtistCredit))
-	for _, artist := range recording.ArtistCredit {
-		artistMBIDs = append(artistMBIDs, artist.Artist.ID)
-	}
-	track := listenbrainz.Track{
-		TrackName:  recording.Title,
-		ArtistName: recording.ArtistCredit.String(),
-		MBIDMapping: &listenbrainz.MBIDMapping{
-			// In case of redirects this MBID differs from the looked up MBID
-			RecordingMBID: recording.ID,
-			ArtistMBIDs:   artistMBIDs,
-		},
-	}
-	return &track, nil
-}
-
 func AsListen(lbListen listenbrainz.Listen) models.Listen {
 	listen := models.Listen{
 		ListenedAt: time.Unix(lbListen.ListenedAt, 0),
@@ -113,3 +84,107 @@ func AsTrack(t listenbrainz.Track) models.Track {
 
 	return track
 }
+
+func LookupRecording(
+	ctx context.Context,
+	mb *musicbrainzws2.Client,
+	mbid mbtypes.MBID,
+) (*listenbrainz.Track, error) {
+	filter := musicbrainzws2.IncludesFilter{
+		Includes: []string{"artist-credits"},
+	}
+	recording, err := mb.LookupRecording(ctx, mbid, filter)
+	if err != nil {
+		return nil, err
+	}
+
+	artistMBIDs := make([]mbtypes.MBID, 0, len(recording.ArtistCredit))
+	for _, artist := range recording.ArtistCredit {
+		artistMBIDs = append(artistMBIDs, artist.Artist.ID)
+	}
+	track := listenbrainz.Track{
+		TrackName:  recording.Title,
+		ArtistName: recording.ArtistCredit.String(),
+		MBIDMapping: &listenbrainz.MBIDMapping{
+			// In case of redirects this MBID differs from the looked up MBID
+			RecordingMBID: recording.ID,
+			ArtistMBIDs:   artistMBIDs,
+		},
+	}
+	return &track, nil
+}
+
+func ExtendTrackMetadata(
+	ctx context.Context,
+	lb *listenbrainz.Client,
+	mb *musicbrainzws2.Client,
+	feedbacks *[]listenbrainz.Feedback,
+) ([]models.Love, error) {
+	mbids := make([]mbtypes.MBID, 0, len(*feedbacks))
+	for _, feedback := range *feedbacks {
+		if feedback.TrackMetadata == nil && feedback.RecordingMBID != "" {
+			mbids = append(mbids, feedback.RecordingMBID)
+		}
+	}
+	result, err := lb.MetadataRecordings(ctx, mbids)
+	if err != nil {
+		return nil, err
+	}
+
+	loves := make([]models.Love, 0, len(*feedbacks))
+	for _, feedback := range *feedbacks {
+		if feedback.TrackMetadata == nil && feedback.RecordingMBID != "" {
+			metadata, ok := result[feedback.RecordingMBID]
+			if ok {
+				feedback.TrackMetadata = trackFromMetadataLookup(
+					feedback.RecordingMBID, metadata)
+			} else {
+				// MBID not in result. This is probably a MBID redirect, get
+				// data from MB instead (slower).
+				// If this also fails, just leave the metadata empty.
+				track, err := LookupRecording(ctx, mb, feedback.RecordingMBID)
+				if err == nil {
+					feedback.TrackMetadata = track
+				}
+			}
+		}
+
+		loves = append(loves, AsLove(feedback))
+	}
+
+	return loves, nil
+}
+
+func trackFromMetadataLookup(
+	recordingMBID mbtypes.MBID,
+	metadata listenbrainz.RecordingMetadata,
+) *listenbrainz.Track {
+	artistMBIDs := make([]mbtypes.MBID, 0, len(metadata.Artist.Artists))
+	artists := make([]listenbrainz.Artist, 0, len(metadata.Artist.Artists))
+	for _, artist := range metadata.Artist.Artists {
+		artistMBIDs = append(artistMBIDs, artist.ArtistMBID)
+		artists = append(artists, listenbrainz.Artist{
+			ArtistCreditName: artist.Name,
+			ArtistMBID:       artist.ArtistMBID,
+			JoinPhrase:       artist.JoinPhrase,
+		})
+	}
+
+	return &listenbrainz.Track{
+		TrackName:   metadata.Recording.Name,
+		ArtistName:  metadata.Artist.Name,
+		ReleaseName: metadata.Release.Name,
+		AdditionalInfo: map[string]any{
+			"duration_ms":        metadata.Recording.Length,
+			"release_group_mbid": metadata.Release.ReleaseGroupMBID,
+		},
+		MBIDMapping: &listenbrainz.MBIDMapping{
+			RecordingMBID:  recordingMBID,
+			ReleaseMBID:    metadata.Release.MBID,
+			ArtistMBIDs:    artistMBIDs,
+			Artists:        artists,
+			CAAID:          metadata.Release.CAAID,
+			CAAReleaseMBID: metadata.Release.CAAReleaseMBID,
+		},
+	}
+}