feat: use AUDIO_FILES extension for retrieving track audio files

Author: devgianlu

player/player.go

@@ -12,6 +12,7 @@ import (
 	"github.com/devgianlu/go-librespot/output"
 	downloadpb "github.com/devgianlu/go-librespot/proto/spotify/download"
 	extmetadatapb "github.com/devgianlu/go-librespot/proto/spotify/extendedmetadata"
+	audiofilespb "github.com/devgianlu/go-librespot/proto/spotify/extendedmetadata/audiofiles"
 	metadatapb "github.com/devgianlu/go-librespot/proto/spotify/metadata"
 	"github.com/devgianlu/go-librespot/spclient"
 	"github.com/devgianlu/go-librespot/vorbis"
@@ -495,19 +496,18 @@ func (p *Player) NewStream(ctx context.Context, client *http.Client, spotId libr
 			return nil, librespot.ErrMediaRestricted
 		}
 
-		if len(trackMeta.File) == 0 {
-			for _, alt := range trackMeta.Alternative {
-				if len(alt.File) == 0 {
-					continue
-				}
-
-				trackMeta.File = append(trackMeta.File, alt.File...)
-			}
+		var audioFilesResp audiofilespb.AudioFilesExtensionResponse
+		err = p.sp.ExtendedMetadataSimple(ctx, spotId, extmetadatapb.ExtensionKind_AUDIO_FILES, &audioFilesResp)
+		if err != nil {
+			return nil, fmt.Errorf("failed getting audio files metadata: %w", err)
+		}
 
-			log.Warnf("original track has no formats, alternatives have a total of %d", len(trackMeta.File))
+		var audioFiles []*metadatapb.AudioFile
+		for _, f := range audioFilesResp.Files {
+			audioFiles = append(audioFiles, f.File)
 		}
 
-		file = selectBestMediaFormat(trackMeta.File, bitrate)
+		file = selectBestMediaFormat(audioFiles, bitrate)
 		if file == nil {
 			return nil, librespot.ErrNoSupportedFormats
 		}

proto/spotify/extendedmetadata/audiofiles/audio_files_extension.pb.go

@@ -0,0 +1,24 @@
+syntax = "proto3";
+
+package spotify.extendedmetadata.audiofiles;
+
+import "spotify/metadata/metadata.proto";
+
+message NormalizationParams {
+  float loudness_db = 1;
+  float true_peak_db = 2;
+}
+
+message ExtendedAudioFile {
+  spotify.metadata.AudioFile file = 1;
+  int32 average_bitrate = 4;
+
+  reserved 2, 3;
+}
+
+message AudioFilesExtensionResponse {
+  repeated ExtendedAudioFile files = 1;
+  NormalizationParams default_file_normalization_params = 2;
+  NormalizationParams default_album_normalization_params = 3;
+  bytes audio_id = 4;
+}