fix: split listenbrainz spotify artist credits

engine/handlers/lbz_submit_listen.go

@@ -69,6 +69,7 @@ type LbzAdditionalInfo struct {
 	Duration                int32    `json:"duration,omitempty"`
 	Tags                    []string `json:"tags,omitempty"`
 	AlbumArtist             string   `json:"albumartist,omitempty"`
+	SpotifyArtistIDs        []string `json:"spotify_artist_ids,omitempty"`
 }
 
 const (
@@ -153,7 +154,7 @@ func LbzSubmitListenHandler(store submitListenHandlerStore, mbzc mbz.MusicBrainz
 			}
 			if len(artistMbzIDs) < 1 {
 				l.Debug().AnErr("error", err).Msg("LbzSubmitListenHandler: Attempting to parse artist UUIDs from mbid_mapping")
-				utils.ParseUUIDSlice(payload.TrackMeta.MBIDMapping.ArtistMBIDs)
+				artistMbzIDs, err = utils.ParseUUIDSlice(payload.TrackMeta.MBIDMapping.ArtistMBIDs)
 				if err != nil {
 					l.Debug().AnErr("error", err).Msg("LbzSubmitListenHandler: Failed to parse one or more UUIDs")
 				}
@@ -208,9 +209,14 @@ func LbzSubmitListenHandler(store submitListenHandlerStore, mbzc mbz.MusicBrainz
 				artistMbidMap = append(artistMbidMap, catalog.ArtistMbidMap{Artist: a.ArtistName, Mbid: mbid})
 			}
 
+			artistNames := payload.TrackMeta.AdditionalInfo.ArtistNames
+			if len(artistNames) < 1 {
+				artistNames = catalog.InferArtistNamesFromSourceIDs(payload.TrackMeta.ArtistName, payload.TrackMeta.AdditionalInfo.SpotifyArtistIDs)
+			}
+
 			opts := catalog.SubmitListenOpts{
 				MbzCaller:          mbzc,
-				ArtistNames:        payload.TrackMeta.AdditionalInfo.ArtistNames,
+				ArtistNames:        artistNames,
 				Artist:             payload.TrackMeta.ArtistName,
 				ArtistMbzIDs:       artistMbzIDs,
 				TrackTitle:         payload.TrackMeta.TrackName,

internal/catalog/catalog.go

@@ -215,9 +215,34 @@ var (
 	inlineFeatPattern = regexp.MustCompile(`(?i)[fF]eat\. ([^()\[\]]+)$`)
 
 	// Delimiters only used inside feat. sections
-	featSplitDelimiters = regexp.MustCompile(`(?i)\s*(?:,|&|and|·)\s*`)
+	featSplitDelimiters  = regexp.MustCompile(`(?i)\s*(?:,|&|and|·)\s*`)
+	commaArtistDelimiter = regexp.MustCompile(`\s*,\s*`)
 )
 
+// InferArtistNamesFromSourceIDs splits artist credits when a source gives one
+// external artist ID per comma-delimited name but no explicit artist_names list.
+func InferArtistNamesFromSourceIDs(artist string, sourceIDs []string) []string {
+	if len(sourceIDs) < 2 {
+		return nil
+	}
+
+	parts := commaArtistDelimiter.Split(artist, -1)
+	if len(parts) != len(sourceIDs) {
+		return nil
+	}
+
+	artists := make([]string, 0, len(parts))
+	for _, part := range parts {
+		part = strings.TrimSpace(part)
+		if part == "" {
+			return nil
+		}
+		artists = append(artists, part)
+	}
+
+	return artists
+}
+
 // ParseArtists extracts all contributing artist names from the artist and title strings
 func ParseArtists(artist string, title string, addlSeparators []*regexp.Regexp) []string {
 	seen := make(map[string]struct{})

internal/catalog/catalog_test.go

@@ -379,3 +379,12 @@ func TestArtistStringParse(t *testing.T) {
 		assert.ElementsMatch(t, out, artists)
 	}
 }
+
+func TestInferArtistNamesFromSourceIDs(t *testing.T) {
+	assert.Equal(t,
+		[]string{"Pineapple StormTv", "Sant", "Tiago Mac"},
+		catalog.InferArtistNamesFromSourceIDs("Pineapple StormTv, Sant, Tiago Mac", []string{"spotify:1", "spotify:2", "spotify:3"}),
+	)
+	assert.Nil(t, catalog.InferArtistNamesFromSourceIDs("Tyler, The Creator", []string{"spotify:1"}))
+	assert.Nil(t, catalog.InferArtistNamesFromSourceIDs("Earth, Wind & Fire, Foo", []string{"spotify:1", "spotify:2"}))
+}

internal/importer/listenbrainz.go

@@ -88,7 +88,7 @@ func ImportListenBrainzFile(ctx context.Context, store importStore, mbzc mbz.Mus
 		}
 		if len(artistMbzIDs) < 1 {
 			l.Debug().AnErr("error", err).Msg("ImportListenBrainzFile: Attempting to parse artist UUIDs from mbid_mapping")
-			utils.ParseUUIDSlice(payload.TrackMeta.MBIDMapping.ArtistMBIDs)
+			artistMbzIDs, err = utils.ParseUUIDSlice(payload.TrackMeta.MBIDMapping.ArtistMBIDs)
 			if err != nil {
 				l.Debug().AnErr("error", err).Msg("ImportListenBrainzFile: Failed to parse one or more UUIDs")
 			}
@@ -138,9 +138,14 @@ func ImportListenBrainzFile(ctx context.Context, store importStore, mbzc mbz.Mus
 			artistMbidMap = append(artistMbidMap, catalog.ArtistMbidMap{Artist: a.ArtistName, Mbid: mbid})
 		}
 
+		artistNames := payload.TrackMeta.AdditionalInfo.ArtistNames
+		if len(artistNames) < 1 {
+			artistNames = catalog.InferArtistNamesFromSourceIDs(payload.TrackMeta.ArtistName, payload.TrackMeta.AdditionalInfo.SpotifyArtistIDs)
+		}
+
 		opts := catalog.SubmitListenOpts{
 			MbzCaller:          mbzc,
-			ArtistNames:        payload.TrackMeta.AdditionalInfo.ArtistNames,
+			ArtistNames:        artistNames,
 			Artist:             payload.TrackMeta.ArtistName,
 			ArtistMbzIDs:       artistMbzIDs,
 			TrackTitle:         payload.TrackMeta.TrackName,