v3.6.5: audio format conversion, PC v7.0.8 backend merge, Amazon re-enabled

go_backend/amazon.go

@@ -31,6 +31,8 @@ type AmazonDownloader struct {
 var (
 	globalAmazonDownloader *AmazonDownloader
 	amazonDownloaderOnce   sync.Once
+	amazonASINRegex        = regexp.MustCompile(`(?i)^B[0-9A-Z]{9}$`)
+	amazonASINFindRegex    = regexp.MustCompile(`(?i)B[0-9A-Z]{9}`)
 )
 
 // AfkarXYZResponse is the response from AfkarXYZ API
@@ -43,6 +45,12 @@ type AfkarXYZResponse struct {
 	} `json:"data"`
 }
 
+// AmazonStreamResponse is the new response format from amazon.afkarxyz.fun/api/track/{asin}
+type AmazonStreamResponse struct {
+	StreamURL     string `json:"streamUrl"`
+	DecryptionKey string `json:"decryptionKey"`
+}
+
 func NewAmazonDownloader() *AmazonDownloader {
 	amazonDownloaderOnce.Do(func() {
 		globalAmazonDownloader = &AmazonDownloader{
@@ -52,10 +60,9 @@ func NewAmazonDownloader() *AmazonDownloader {
 	return globalAmazonDownloader
 }
 
-// fetchAmazonURLWithRetry fetches from AfkarXYZ API with retry logic for mobile networks
-func (a *AmazonDownloader) fetchAmazonURLWithRetry(amazonURL string) (string, string, error) {
-	apiURL := "https://amazon.afkarxyz.fun/convert?url=" + url.QueryEscape(amazonURL)
-
+// fetchAmazonURLWithRetry fetches from AfkarXYZ API with retry logic for mobile networks.
+// Returns downloadURL, suggested fileName, optional decryptionKey.
+func (a *AmazonDownloader) fetchAmazonURLWithRetry(amazonURL string) (string, string, string, error) {
 	var lastErr error
 	for attempt := 0; attempt <= amazonMaxRetries; attempt++ {
 		if attempt > 0 {
@@ -64,66 +71,184 @@ func (a *AmazonDownloader) fetchAmazonURLWithRetry(amazonURL string) (string, st
 			time.Sleep(delay)
 		}
 
-		downloadURL, fileName, err := a.doAfkarXYZRequest(apiURL)
+		downloadURL, fileName, decryptionKey, err := a.doAfkarXYZRequest(amazonURL)
 		if err == nil {
-			return downloadURL, fileName, nil
+			return downloadURL, fileName, decryptionKey, nil
 		}
 
 		lastErr = err
-		errStr := err.Error()
+		errStr := strings.ToLower(err.Error())
 
 		// Check if error is retryable
 		isRetryable := strings.Contains(errStr, "timeout") ||
 			strings.Contains(errStr, "connection reset") ||
 			strings.Contains(errStr, "connection refused") ||
-			strings.Contains(errStr, "EOF") ||
+			strings.Contains(errStr, "eof") ||
 			strings.Contains(errStr, "status 5") ||
-			strings.Contains(errStr, "status 429")
+			strings.Contains(errStr, "status 429") ||
+			strings.Contains(errStr, "http 429")
 
 		if !isRetryable {
-			return "", "", err
+			return "", "", "", err
 		}
 
 		GoLog("[Amazon] Attempt %d failed (retryable): %v\n", attempt+1, err)
 	}
 
-	return "", "", fmt.Errorf("all %d attempts failed: %w", amazonMaxRetries+1, lastErr)
+	return "", "", "", fmt.Errorf("all %d attempts failed: %w", amazonMaxRetries+1, lastErr)
 }
 
-// doAfkarXYZRequest performs a single request to AfkarXYZ API
-func (a *AmazonDownloader) doAfkarXYZRequest(apiURL string) (string, string, error) {
+func normalizeAmazonASIN(candidate string) string {
+	trimmed := strings.TrimSpace(candidate)
+	if trimmed == "" {
+		return ""
+	}
+
+	if decoded, err := url.QueryUnescape(trimmed); err == nil {
+		trimmed = decoded
+	}
+
+	trimmed = strings.ToUpper(trimmed)
+	if idx := strings.IndexAny(trimmed, "?#&/"); idx >= 0 {
+		trimmed = trimmed[:idx]
+	}
+
+	if amazonASINRegex.MatchString(trimmed) {
+		return trimmed
+	}
+
+	return ""
+}
+
+func extractAmazonASIN(amazonURL string) string {
+	raw := strings.TrimSpace(amazonURL)
+	if raw == "" {
+		return ""
+	}
+
+	parsed, err := url.Parse(raw)
+	if err == nil {
+		query := parsed.Query()
+
+		// Prefer track-level ASIN when URL also contains albumAsin.
+		for _, key := range []string{"trackAsin", "trackasin", "trackASIN", "asin", "ASIN", "i"} {
+			if asin := normalizeAmazonASIN(query.Get(key)); asin != "" {
+				return asin
+			}
+		}
+
+		path := strings.Trim(parsed.Path, "/")
+		if path != "" {
+			segments := strings.Split(path, "/")
+
+			for i := 0; i < len(segments)-1; i++ {
+				segment := strings.ToLower(strings.TrimSpace(segments[i]))
+				if segment == "track" || segment == "tracks" {
+					if asin := normalizeAmazonASIN(segments[i+1]); asin != "" {
+						return asin
+					}
+				}
+			}
+
+			if asin := normalizeAmazonASIN(segments[len(segments)-1]); asin != "" {
+				return asin
+			}
+		}
+	}
+
+	match := amazonASINFindRegex.FindString(strings.ToUpper(raw))
+	return normalizeAmazonASIN(match)
+}
+
+// doAfkarXYZRequest performs a single request to Amazon API.
+// It tries new endpoint first, then falls back to legacy /convert endpoint.
+func (a *AmazonDownloader) doAfkarXYZRequest(amazonURL string) (string, string, string, error) {
+	asin := extractAmazonASIN(amazonURL)
+	if asin != "" {
+		GoLog("[Amazon] Using ASIN: %s\n", asin)
+		downloadURL, fileName, decryptKey, err := a.doAfkarXYZRequestNew(asin)
+		if err == nil {
+			return downloadURL, fileName, decryptKey, nil
+		}
+		GoLog("[Amazon] New API failed for ASIN %s, trying legacy endpoint: %v\n", asin, err)
+	}
+	return a.doAfkarXYZRequestLegacy(amazonURL)
+}
+
+func (a *AmazonDownloader) doAfkarXYZRequestNew(asin string) (string, string, string, error) {
 	ctx, cancel := context.WithTimeout(context.Background(), amazonAPITimeoutMobile)
 	defer cancel()
 
+	apiURL := fmt.Sprintf("https://amazon.afkarxyz.fun/api/track/%s", asin)
 	req, err := http.NewRequestWithContext(ctx, "GET", apiURL, nil)
 	if err != nil {
-		return "", "", fmt.Errorf("failed to create request: %w", err)
+		return "", "", "", fmt.Errorf("failed to create request: %w", err)
+	}
+
+	req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/144.0.0.0 Safari/537.36")
+
+	resp, err := a.client.Do(req)
+	if err != nil {
+		return "", "", "", fmt.Errorf("failed to call Amazon API: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != 200 {
+		return "", "", "", fmt.Errorf("Amazon API returned status %d", resp.StatusCode)
+	}
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return "", "", "", fmt.Errorf("failed to read response: %w", err)
+	}
+
+	var apiResp AmazonStreamResponse
+	if err := json.Unmarshal(body, &apiResp); err != nil {
+		return "", "", "", fmt.Errorf("failed to decode response: %w", err)
+	}
+
+	if strings.TrimSpace(apiResp.StreamURL) == "" {
+		return "", "", "", fmt.Errorf("Amazon API returned empty stream URL")
+	}
+
+	fileName := asin + ".m4a"
+	return apiResp.StreamURL, fileName, strings.TrimSpace(apiResp.DecryptionKey), nil
+}
+
+func (a *AmazonDownloader) doAfkarXYZRequestLegacy(amazonURL string) (string, string, string, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), amazonAPITimeoutMobile)
+	defer cancel()
+
+	apiURL := "https://amazon.afkarxyz.fun/convert?url=" + url.QueryEscape(amazonURL)
+	req, err := http.NewRequestWithContext(ctx, "GET", apiURL, nil)
+	if err != nil {
+		return "", "", "", fmt.Errorf("failed to create legacy request: %w", err)
 	}
 
 	req.Header.Set("User-Agent", getRandomUserAgent())
 
 	resp, err := a.client.Do(req)
 	if err != nil {
-		return "", "", fmt.Errorf("failed to call AfkarXYZ API: %w", err)
+		return "", "", "", fmt.Errorf("failed to call legacy AfkarXYZ API: %w", err)
 	}
 	defer resp.Body.Close()
 
 	if resp.StatusCode != 200 {
-		return "", "", fmt.Errorf("AfkarXYZ API returned status %d", resp.StatusCode)
+		return "", "", "", fmt.Errorf("legacy AfkarXYZ API returned status %d", resp.StatusCode)
 	}
 
 	body, err := io.ReadAll(resp.Body)
 	if err != nil {
-		return "", "", fmt.Errorf("failed to read response: %w", err)
+		return "", "", "", fmt.Errorf("failed to read legacy response: %w", err)
 	}
 
 	var apiResp AfkarXYZResponse
 	if err := json.Unmarshal(body, &apiResp); err != nil {
-		return "", "", fmt.Errorf("failed to decode response: %w", err)
+		return "", "", "", fmt.Errorf("failed to decode legacy response: %w", err)
 	}
 
-	if !apiResp.Success || apiResp.Data.DirectLink == "" {
-		return "", "", fmt.Errorf("AfkarXYZ API failed or no download link found")
+	if !apiResp.Success || strings.TrimSpace(apiResp.Data.DirectLink) == "" {
+		return "", "", "", fmt.Errorf("legacy AfkarXYZ API failed or no download link found")
 	}
 
 	fileName := apiResp.Data.FileName
@@ -134,19 +259,22 @@ func (a *AmazonDownloader) doAfkarXYZRequest(apiURL string) (string, string, err
 	reg := regexp.MustCompile(`[<>:"/\\|?*]`)
 	fileName = reg.ReplaceAllString(fileName, "")
 
-	return apiResp.Data.DirectLink, fileName, nil
+	return apiResp.Data.DirectLink, fileName, "", nil
 }
 
-func (a *AmazonDownloader) downloadFromAfkarXYZ(amazonURL string) (string, string, error) {
+func (a *AmazonDownloader) downloadFromAfkarXYZ(amazonURL string) (string, string, string, error) {
 	GoLog("[Amazon] Fetching from AfkarXYZ API...\n")
 
-	downloadURL, fileName, err := a.fetchAmazonURLWithRetry(amazonURL)
+	downloadURL, fileName, decryptionKey, err := a.fetchAmazonURLWithRetry(amazonURL)
 	if err != nil {
-		return "", "", err
+		return "", "", "", err
 	}
 
+	if decryptionKey != "" {
+		GoLog("[Amazon] AfkarXYZ returned encrypted stream (decryption key available)\n")
+	}
 	GoLog("[Amazon] AfkarXYZ returned: %s\n", fileName)
-	return downloadURL, fileName, nil
+	return downloadURL, fileName, decryptionKey, nil
 }
 
 func (a *AmazonDownloader) DownloadFile(downloadURL, outputPath string, outputFD int, itemID string) error {
@@ -233,17 +361,18 @@ func (a *AmazonDownloader) DownloadFile(downloadURL, outputPath string, outputFD
 
 // AmazonDownloadResult contains download result with quality info
 type AmazonDownloadResult struct {
-	FilePath    string
-	BitDepth    int
-	SampleRate  int
-	Title       string
-	Artist      string
-	Album       string
-	ReleaseDate string
-	TrackNumber int
-	DiscNumber  int
-	ISRC        string
-	LyricsLRC   string
+	FilePath      string
+	BitDepth      int
+	SampleRate    int
+	Title         string
+	Artist        string
+	Album         string
+	ReleaseDate   string
+	TrackNumber   int
+	DiscNumber    int
+	ISRC          string
+	LyricsLRC     string
+	DecryptionKey string
 }
 
 func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
@@ -299,7 +428,7 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 	}
 
 	// Download using AfkarXYZ API
-	downloadURL, _, err := downloader.downloadFromAfkarXYZ(amazonURL)
+	downloadURL, afkarFileName, decryptionKey, err := downloader.downloadFromAfkarXYZ(amazonURL)
 	if err != nil {
 		return AmazonDownloadResult{}, fmt.Errorf("failed to get download URL from AfkarXYZ: %w", err)
 	}
@@ -321,7 +450,11 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 			outputPath = fmt.Sprintf("/proc/self/fd/%d", req.OutputFD)
 		}
 	} else {
-		filename = sanitizeFilename(filename) + ".flac"
+		outputExt := strings.ToLower(filepath.Ext(afkarFileName))
+		if outputExt == "" {
+			outputExt = ".flac"
+		}
+		filename = sanitizeFilename(filename) + outputExt
 		outputPath = filepath.Join(req.OutputDir, filename)
 		if fileInfo, statErr := os.Stat(outputPath); statErr == nil && fileInfo.Size() > 0 {
 			return AmazonDownloadResult{FilePath: "EXISTS:" + outputPath}, nil
@@ -352,6 +485,12 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 		return AmazonDownloadResult{}, fmt.Errorf("download failed: %w", err)
 	}
 
+	actualOutputPath := outputPath
+	needsDecryption := strings.TrimSpace(decryptionKey) != ""
+	if needsDecryption {
+		GoLog("[Amazon] Download requires decryption; deferring decrypt to Flutter FFmpeg path\n")
+	}
+
 	// Wait for parallel operations to complete
 	<-parallelDone
 
@@ -360,7 +499,6 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 		SetItemFinalizing(req.ItemID)
 	}
 
-	existingMeta, metaErr := ReadMetadata(outputPath)
 	actualTrackNum := req.TrackNumber
 	actualDiscNum := req.DiscNumber
 	actualDate := req.ReleaseDate
@@ -368,25 +506,28 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 	actualTitle := req.TrackName
 	actualArtist := req.ArtistName
 
-	if metaErr == nil && existingMeta != nil {
-		if existingMeta.TrackNumber > 0 && (req.TrackNumber == 0 || req.TrackNumber == 1) {
-			actualTrackNum = existingMeta.TrackNumber
-			GoLog("[Amazon] Using track number from file: %d (request had: %d)\n", actualTrackNum, req.TrackNumber)
+	if !needsDecryption {
+		existingMeta, metaErr := ReadMetadata(actualOutputPath)
+		if metaErr == nil && existingMeta != nil {
+			if existingMeta.TrackNumber > 0 && (req.TrackNumber == 0 || req.TrackNumber == 1) {
+				actualTrackNum = existingMeta.TrackNumber
+				GoLog("[Amazon] Using track number from file: %d (request had: %d)\n", actualTrackNum, req.TrackNumber)
+			}
+			if existingMeta.DiscNumber > 0 && (req.DiscNumber == 0 || req.DiscNumber == 1) {
+				actualDiscNum = existingMeta.DiscNumber
+				GoLog("[Amazon] Using disc number from file: %d (request had: %d)\n", actualDiscNum, req.DiscNumber)
+			}
+			if existingMeta.Date != "" && req.ReleaseDate == "" {
+				actualDate = existingMeta.Date
+				GoLog("[Amazon] Using release date from file: %s\n", actualDate)
+			}
+			if existingMeta.Album != "" && req.AlbumName == "" {
+				actualAlbum = existingMeta.Album
+				GoLog("[Amazon] Using album from file: %s\n", actualAlbum)
+			}
+			GoLog("[Amazon] Existing metadata - Title: %s, Artist: %s, Album: %s, Date: %s\n",
+				existingMeta.Title, existingMeta.Artist, existingMeta.Album, existingMeta.Date)
 		}
-		if existingMeta.DiscNumber > 0 && (req.DiscNumber == 0 || req.DiscNumber == 1) {
-			actualDiscNum = existingMeta.DiscNumber
-			GoLog("[Amazon] Using disc number from file: %d (request had: %d)\n", actualDiscNum, req.DiscNumber)
-		}
-		if existingMeta.Date != "" && req.ReleaseDate == "" {
-			actualDate = existingMeta.Date
-			GoLog("[Amazon] Using release date from file: %s\n", actualDate)
-		}
-		if existingMeta.Album != "" && req.AlbumName == "" {
-			actualAlbum = existingMeta.Album
-			GoLog("[Amazon] Using album from file: %s\n", actualAlbum)
-		}
-		GoLog("[Amazon] Existing metadata - Title: %s, Artist: %s, Album: %s, Date: %s\n",
-			existingMeta.Title, existingMeta.Artist, existingMeta.Album, existingMeta.Date)
 	}
 
 	metadata := Metadata{
@@ -409,7 +550,7 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 		coverData = parallelResult.CoverData
 		GoLog("[Amazon] Using parallel-fetched cover (%d bytes)\n", len(coverData))
 	} else {
-		existingCover, coverErr := ExtractCoverArt(outputPath)
+		existingCover, coverErr := ExtractCoverArt(actualOutputPath)
 		if coverErr == nil && len(existingCover) > 0 {
 			coverData = existingCover
 			GoLog("[Amazon] Using existing cover from Amazon file (%d bytes)\n", len(coverData))
@@ -418,11 +559,16 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 		}
 	}
 
-	if isSafOutput {
+	if isSafOutput || needsDecryption {
 		GoLog("[Amazon] SAF output detected - skipping in-backend metadata/lyrics embedding (handled in Flutter)\n")
 	} else {
-		if err := EmbedMetadataWithCoverData(outputPath, metadata, coverData); err != nil {
-			GoLog("[Amazon] Warning: failed to embed metadata: %v\n", err)
+		isFlacOutput := strings.HasSuffix(strings.ToLower(actualOutputPath), ".flac")
+		if isFlacOutput {
+			if err := EmbedMetadataWithCoverData(actualOutputPath, metadata, coverData); err != nil {
+				GoLog("[Amazon] Warning: failed to embed metadata: %v\n", err)
+			}
+		} else {
+			GoLog("[Amazon] Non-FLAC output detected (%s), skipping native metadata embedding\n", filepath.Ext(actualOutputPath))
 		}
 
 		if req.EmbedLyrics && parallelResult != nil && parallelResult.LyricsLRC != "" {
@@ -433,20 +579,22 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 
 			if lyricsMode == "external" || lyricsMode == "both" {
 				GoLog("[Amazon] Saving external LRC file...\n")
-				if lrcPath, lrcErr := SaveLRCFile(outputPath, parallelResult.LyricsLRC); lrcErr != nil {
+				if lrcPath, lrcErr := SaveLRCFile(actualOutputPath, parallelResult.LyricsLRC); lrcErr != nil {
 					GoLog("[Amazon] Warning: failed to save LRC file: %v\n", lrcErr)
 				} else {
 					GoLog("[Amazon] LRC file saved: %s\n", lrcPath)
 				}
 			}
 
-			if lyricsMode == "embed" || lyricsMode == "both" {
+			if (lyricsMode == "embed" || lyricsMode == "both") && isFlacOutput {
 				GoLog("[Amazon] Embedding parallel-fetched lyrics (%d lines)...\n", len(parallelResult.LyricsData.Lines))
-				if embedErr := EmbedLyrics(outputPath, parallelResult.LyricsLRC); embedErr != nil {
+				if embedErr := EmbedLyrics(actualOutputPath, parallelResult.LyricsLRC); embedErr != nil {
 					GoLog("[Amazon] Warning: failed to embed lyrics: %v\n", embedErr)
 				} else {
 					GoLog("[Amazon] Lyrics embedded successfully\n")
 				}
+			} else if (lyricsMode == "embed" || lyricsMode == "both") && !isFlacOutput {
+				GoLog("[Amazon] Skipping embedded lyrics for non-FLAC output\n")
 			}
 		} else if req.EmbedLyrics {
 			GoLog("[Amazon] No lyrics available from parallel fetch\n")
@@ -456,17 +604,17 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 	GoLog("[Amazon] Downloaded successfully from Amazon Music\n")
 
 	quality := AudioQuality{}
-	if isSafOutput {
+	if isSafOutput || needsDecryption {
 		GoLog("[Amazon] SAF output detected - skipping post-write file inspection in backend\n")
 	} else {
-		quality, err = GetAudioQuality(outputPath)
+		quality, err = GetAudioQuality(actualOutputPath)
 		if err != nil {
 			GoLog("[Amazon] Warning: couldn't read quality from file: %v\n", err)
 		} else {
 			GoLog("[Amazon] Actual quality: %d-bit/%dHz\n", quality.BitDepth, quality.SampleRate)
 		}
 
-		finalMeta, metaReadErr := ReadMetadata(outputPath)
+		finalMeta, metaReadErr := ReadMetadata(actualOutputPath)
 		if metaReadErr == nil && finalMeta != nil {
 			GoLog("[Amazon] Final metadata from file - Track: %d, Disc: %d, Date: %s\n",
 				finalMeta.TrackNumber, finalMeta.DiscNumber, finalMeta.Date)
@@ -478,9 +626,10 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 		}
 	}
 
-	// Add to ISRC index for fast duplicate checking
-	if !isSafOutput {
-		AddToISRCIndex(req.OutputDir, req.ISRC, outputPath)
+	// Add to ISRC index for fast duplicate checking.
+	// When decryption is pending in Flutter, postpone indexing until final file is settled.
+	if !isSafOutput && !needsDecryption {
+		AddToISRCIndex(req.OutputDir, req.ISRC, actualOutputPath)
 	}
 
 	bitDepth := 0
@@ -496,16 +645,17 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 	}
 
 	return AmazonDownloadResult{
-		FilePath:    outputPath,
-		BitDepth:    bitDepth,
-		SampleRate:  sampleRate,
-		Title:       req.TrackName,
-		Artist:      req.ArtistName,
-		Album:       req.AlbumName,
-		ReleaseDate: req.ReleaseDate,
-		TrackNumber: actualTrackNum,
-		DiscNumber:  actualDiscNum,
-		ISRC:        req.ISRC,
-		LyricsLRC:   lyricsLRC,
+		FilePath:      outputPath,
+		BitDepth:      bitDepth,
+		SampleRate:    sampleRate,
+		Title:         req.TrackName,
+		Artist:        req.ArtistName,
+		Album:         req.AlbumName,
+		ReleaseDate:   req.ReleaseDate,
+		TrackNumber:   actualTrackNum,
+		DiscNumber:    actualDiscNum,
+		ISRC:          req.ISRC,
+		LyricsLRC:     lyricsLRC,
+		DecryptionKey: decryptionKey,
 	}, nil
 }

go_backend/amazon_asin_test.go

@@ -0,0 +1,46 @@
+package gobackend
+
+import "testing"
+
+func TestExtractAmazonASIN(t *testing.T) {
+	tests := []struct {
+		name string
+		url  string
+		want string
+	}{
+		{
+			name: "prefers trackAsin over albumAsin",
+			url:  "https://music.amazon.com/albums/B0ALBUM123?trackAsin=B0TRACK456&musicTerritory=US",
+			want: "B0TRACK456",
+		},
+		{
+			name: "extract from tracks path",
+			url:  "https://music.amazon.com/tracks/B0CYQHGWZJ?musicTerritory=US",
+			want: "B0CYQHGWZJ",
+		},
+		{
+			name: "extract from plain query asin",
+			url:  "https://example.com/?asin=B0CYQHGWZJ",
+			want: "B0CYQHGWZJ",
+		},
+		{
+			name: "fallback regex",
+			url:  "https://example.com/path/B0CYQHGWZJ",
+			want: "B0CYQHGWZJ",
+		},
+		{
+			name: "invalid url",
+			url:  "https://music.amazon.com/tracks/not-valid",
+			want: "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := extractAmazonASIN(tt.url)
+			if got != tt.want {
+				t.Fatalf("extractAmazonASIN() = %q, want %q", got, tt.want)
+			}
+		})
+	}
+}

go_backend/audio_metadata.go

@@ -23,6 +23,7 @@ type AudioMetadata struct {
 	TrackNumber int
 	DiscNumber  int
 	ISRC        string
+	Lyrics      string
 	Label       string
 	Copyright   string
 	Composer    string
@@ -181,6 +182,15 @@ func parseID3v22Frames(data []byte, metadata *AudioMetadata, tagUnsync bool) {
 			metadata.Label = value
 		case "TCR":
 			metadata.Copyright = value
+		case "ULT":
+			if v := extractLyricsFrame(frameData); v != "" && metadata.Lyrics == "" {
+				metadata.Lyrics = v
+			}
+		case "TXX":
+			desc, userValue := extractUserTextFrame(frameData)
+			if isLyricsDescription(desc) && userValue != "" && metadata.Lyrics == "" {
+				metadata.Lyrics = userValue
+			}
 		}
 
 		pos += 6 + frameSize
@@ -297,6 +307,15 @@ func parseID3v23Frames(data []byte, metadata *AudioMetadata, version byte, tagUn
 			if v := extractCommentFrame(frameData); v != "" {
 				metadata.Comment = v
 			}
+		case "USLT":
+			if v := extractLyricsFrame(frameData); v != "" && metadata.Lyrics == "" {
+				metadata.Lyrics = v
+			}
+		case "TXXX":
+			desc, userValue := extractUserTextFrame(frameData)
+			if isLyricsDescription(desc) && userValue != "" && metadata.Lyrics == "" {
+				metadata.Lyrics = userValue
+			}
 		}
 
 		pos += 10 + frameSize
@@ -399,6 +418,98 @@ func extractCommentFrame(data []byte) string {
 	return extractTextFrame(framed)
 }
 
+// extractLyricsFrame parses ID3 unsynchronized lyrics frames (USLT/ULT).
+// Format: encoding(1) + language(3) + description(null-terminated) + lyrics text.
+func extractLyricsFrame(data []byte) string {
+	if len(data) < 5 {
+		return ""
+	}
+
+	encoding := data[0]
+	rest := data[4:] // skip 3-byte language code
+
+	var text []byte
+	switch encoding {
+	case 1, 2: // UTF-16 variants use double-null terminator
+		for i := 0; i+1 < len(rest); i += 2 {
+			if rest[i] == 0 && rest[i+1] == 0 {
+				text = rest[i+2:]
+				break
+			}
+		}
+	default: // ISO-8859-1 or UTF-8
+		idx := bytes.IndexByte(rest, 0)
+		if idx >= 0 && idx+1 < len(rest) {
+			text = rest[idx+1:]
+		} else {
+			text = rest
+		}
+	}
+
+	if len(text) == 0 {
+		return ""
+	}
+
+	framed := make([]byte, 1+len(text))
+	framed[0] = encoding
+	copy(framed[1:], text)
+	return extractTextFrame(framed)
+}
+
+// extractUserTextFrame parses ID3 TXXX/TXX user text frame:
+// encoding(1) + description + separator + value.
+func extractUserTextFrame(data []byte) (string, string) {
+	if len(data) < 2 {
+		return "", ""
+	}
+
+	encoding := data[0]
+	payload := data[1:]
+
+	var descRaw, valueRaw []byte
+	switch encoding {
+	case 1, 2: // UTF-16 variants
+		for i := 0; i+1 < len(payload); i += 2 {
+			if payload[i] == 0 && payload[i+1] == 0 {
+				descRaw = payload[:i]
+				valueRaw = payload[i+2:]
+				break
+			}
+		}
+	default: // ISO-8859-1 or UTF-8
+		idx := bytes.IndexByte(payload, 0)
+		if idx >= 0 {
+			descRaw = payload[:idx]
+			if idx+1 <= len(payload) {
+				valueRaw = payload[idx+1:]
+			}
+		}
+	}
+
+	if len(valueRaw) == 0 {
+		return "", ""
+	}
+
+	descFramed := make([]byte, 1+len(descRaw))
+	descFramed[0] = encoding
+	copy(descFramed[1:], descRaw)
+
+	valueFramed := make([]byte, 1+len(valueRaw))
+	valueFramed[0] = encoding
+	copy(valueFramed[1:], valueRaw)
+
+	return strings.TrimSpace(extractTextFrame(descFramed)), strings.TrimSpace(extractTextFrame(valueFramed))
+}
+
+func isLyricsDescription(description string) bool {
+	switch strings.ToLower(strings.TrimSpace(description)) {
+	case "lyrics", "lyric", "unsyncedlyrics", "unsynced lyrics", "lrc":
+		return true
+	default:
+		return false
+	}
+}
+
 func decodeUTF16(data []byte) string {
 	if len(data) < 2 {
 		return ""
@@ -843,6 +954,10 @@ func parseVorbisComments(data []byte, metadata *AudioMetadata) {
 			metadata.Composer = value
 		case "COMMENT", "DESCRIPTION":
 			metadata.Comment = value
+		case "LYRICS", "UNSYNCEDLYRICS":
+			if metadata.Lyrics == "" {
+				metadata.Lyrics = value
+			}
 		case "ORGANIZATION", "LABEL", "PUBLISHER":
 			metadata.Label = value
 		case "COPYRIGHT":

go_backend/exports.go

@@ -47,10 +47,30 @@ func GetSpotifyMetadata(spotifyURL string) (string, error) {
 
 	client, err := NewSpotifyMetadataClient()
 	if err != nil {
+		if shouldTrySpotFetchFallback(err) {
+			data, apiErr := GetSpotifyDataWithAPI(ctx, spotifyURL, DefaultSpotFetchAPIBaseURL)
+			if apiErr == nil {
+				jsonBytes, marshalErr := json.Marshal(data)
+				if marshalErr != nil {
+					return "", marshalErr
+				}
+				return string(jsonBytes), nil
+			}
+		}
 		return "", err
 	}
 	data, err := client.GetFilteredData(ctx, spotifyURL, false, 0)
 	if err != nil {
+		if shouldTrySpotFetchFallback(err) {
+			fallbackData, apiErr := GetSpotifyDataWithAPI(ctx, spotifyURL, DefaultSpotFetchAPIBaseURL)
+			if apiErr == nil {
+				jsonBytes, marshalErr := json.Marshal(fallbackData)
+				if marshalErr != nil {
+					return "", marshalErr
+				}
+				return string(jsonBytes), nil
+			}
+		}
 		return "", err
 	}
 
@@ -178,20 +198,22 @@ type DownloadResponse struct {
 	Copyright              string `json:"copyright,omitempty"`
 	SkipMetadataEnrichment bool   `json:"skip_metadata_enrichment,omitempty"`
 	LyricsLRC              string `json:"lyrics_lrc,omitempty"`
+	DecryptionKey          string `json:"decryption_key,omitempty"`
 }
 
 type DownloadResult struct {
-	FilePath    string
-	BitDepth    int
-	SampleRate  int
-	Title       string
-	Artist      string
-	Album       string
-	ReleaseDate string
-	TrackNumber int
-	DiscNumber  int
-	ISRC        string
-	LyricsLRC   string
+	FilePath      string
+	BitDepth      int
+	SampleRate    int
+	Title         string
+	Artist        string
+	Album         string
+	ReleaseDate   string
+	TrackNumber   int
+	DiscNumber    int
+	ISRC          string
+	LyricsLRC     string
+	DecryptionKey string
 }
 
 func buildDownloadSuccessResponse(
@@ -258,6 +280,7 @@ func buildDownloadSuccessResponse(
 		Label:            req.Label,
 		Copyright:        req.Copyright,
 		LyricsLRC:        result.LyricsLRC,
+		DecryptionKey:    result.DecryptionKey,
 	}
 }
 
@@ -323,17 +346,18 @@ func DownloadTrack(requestJSON string) (string, error) {
 		amazonResult, amazonErr := downloadFromAmazon(req)
 		if amazonErr == nil {
 			result = DownloadResult{
-				FilePath:    amazonResult.FilePath,
-				BitDepth:    amazonResult.BitDepth,
-				SampleRate:  amazonResult.SampleRate,
-				Title:       amazonResult.Title,
-				Artist:      amazonResult.Artist,
-				Album:       amazonResult.Album,
-				ReleaseDate: amazonResult.ReleaseDate,
-				TrackNumber: amazonResult.TrackNumber,
-				DiscNumber:  amazonResult.DiscNumber,
-				ISRC:        amazonResult.ISRC,
-				LyricsLRC:   amazonResult.LyricsLRC,
+				FilePath:      amazonResult.FilePath,
+				BitDepth:      amazonResult.BitDepth,
+				SampleRate:    amazonResult.SampleRate,
+				Title:         amazonResult.Title,
+				Artist:        amazonResult.Artist,
+				Album:         amazonResult.Album,
+				ReleaseDate:   amazonResult.ReleaseDate,
+				TrackNumber:   amazonResult.TrackNumber,
+				DiscNumber:    amazonResult.DiscNumber,
+				ISRC:          amazonResult.ISRC,
+				LyricsLRC:     amazonResult.LyricsLRC,
+				DecryptionKey: amazonResult.DecryptionKey,
 			}
 		}
 		err = amazonErr
@@ -534,17 +558,18 @@ func DownloadWithFallback(requestJSON string) (string, error) {
 			amazonResult, amazonErr := downloadFromAmazon(req)
 			if amazonErr == nil {
 				result = DownloadResult{
-					FilePath:    amazonResult.FilePath,
-					BitDepth:    amazonResult.BitDepth,
-					SampleRate:  amazonResult.SampleRate,
-					Title:       amazonResult.Title,
-					Artist:      amazonResult.Artist,
-					Album:       amazonResult.Album,
-					ReleaseDate: amazonResult.ReleaseDate,
-					TrackNumber: amazonResult.TrackNumber,
-					DiscNumber:  amazonResult.DiscNumber,
-					ISRC:        amazonResult.ISRC,
-					LyricsLRC:   amazonResult.LyricsLRC,
+					FilePath:      amazonResult.FilePath,
+					BitDepth:      amazonResult.BitDepth,
+					SampleRate:    amazonResult.SampleRate,
+					Title:         amazonResult.Title,
+					Artist:        amazonResult.Artist,
+					Album:         amazonResult.Album,
+					ReleaseDate:   amazonResult.ReleaseDate,
+					TrackNumber:   amazonResult.TrackNumber,
+					DiscNumber:    amazonResult.DiscNumber,
+					ISRC:          amazonResult.ISRC,
+					LyricsLRC:     amazonResult.LyricsLRC,
+					DecryptionKey: amazonResult.DecryptionKey,
 				}
 			} else if !errors.Is(amazonErr, ErrDownloadCancelled) {
 				GoLog("[DownloadWithFallback] Amazon error: %v\n", amazonErr)
@@ -699,6 +724,7 @@ func ReadFileMetadata(filePath string) (string, error) {
 			result["track_number"] = meta.TrackNumber
 			result["disc_number"] = meta.DiscNumber
 			result["isrc"] = meta.ISRC
+			result["lyrics"] = meta.Lyrics
 			result["genre"] = meta.Genre
 			result["composer"] = meta.Composer
 			result["comment"] = meta.Comment
@@ -723,6 +749,7 @@ func ReadFileMetadata(filePath string) (string, error) {
 			result["track_number"] = meta.TrackNumber
 			result["disc_number"] = meta.DiscNumber
 			result["isrc"] = meta.ISRC
+			result["lyrics"] = meta.Lyrics
 			result["genre"] = meta.Genre
 			result["composer"] = meta.Composer
 			result["comment"] = meta.Comment
@@ -1178,9 +1205,12 @@ func GetSpotifyMetadataWithDeezerFallback(spotifyURL string) (string, error) {
 	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
 	defer cancel()
 
+	var spotifyErr error
+
 	client, err := NewSpotifyMetadataClient()
 	if err != nil {
 		LogWarn("Spotify", "Credentials not configured, falling back to Deezer")
+		spotifyErr = err
 	} else {
 		data, err := client.GetFilteredData(ctx, spotifyURL, false, 0)
 		if err == nil {
@@ -1191,28 +1221,81 @@ func GetSpotifyMetadataWithDeezerFallback(spotifyURL string) (string, error) {
 			return string(jsonBytes), nil
 		}
 
-		errStr := strings.ToLower(err.Error())
-		if !strings.Contains(errStr, "429") && !strings.Contains(errStr, "rate") && !strings.Contains(errStr, "limit") {
+		spotifyErr = err
+		if !shouldTrySpotFetchFallback(err) {
 			return "", err
 		}
 	}
 
+	spotFetchData, apiErr := GetSpotifyDataWithAPI(ctx, spotifyURL, DefaultSpotFetchAPIBaseURL)
+	if apiErr == nil {
+		GoLog("[Fallback] Spotify metadata fetched via SpotFetch API\n")
+		jsonBytes, err := json.Marshal(spotFetchData)
+		if err != nil {
+			return "", err
+		}
+		return string(jsonBytes), nil
+	}
+	GoLog("[Fallback] SpotFetch API fallback failed: %v\n", apiErr)
+
 	parsed, parseErr := parseSpotifyURI(spotifyURL)
 	if parseErr != nil {
-		return "", fmt.Errorf("spotify rate limited and failed to parse URL: %w", parseErr)
+		if spotifyErr != nil {
+			return "", fmt.Errorf("spotify failed (%v), SpotFetch fallback failed (%v), and URL parsing failed: %w", spotifyErr, apiErr, parseErr)
+		}
+		return "", fmt.Errorf("SpotFetch fallback failed (%v) and URL parsing failed: %w", apiErr, parseErr)
 	}
 
-	GoLog("[Fallback] Spotify rate limited for %s, trying Deezer...\n", parsed.Type)
+	GoLog("[Fallback] Trying Deezer conversion fallback for %s...\n", parsed.Type)
 
 	if parsed.Type == "track" || parsed.Type == "album" {
 		return ConvertSpotifyToDeezer(parsed.Type, parsed.ID)
 	}
 
 	if parsed.Type == "artist" {
-		return "", fmt.Errorf("spotify rate limited. Artist pages require Spotify API - please try again later")
+		if spotifyErr != nil {
+			return "", fmt.Errorf("spotify metadata unavailable (%v) and SpotFetch fallback failed (%v). Artist pages require Spotify/SpotFetch API", spotifyErr, apiErr)
+		}
+		return "", fmt.Errorf("SpotFetch fallback failed (%v). Artist pages require Spotify/SpotFetch API", apiErr)
 	}
 
-	return "", fmt.Errorf("spotify rate limited. Playlists are user-specific and require Spotify API")
+	if spotifyErr != nil {
+		return "", fmt.Errorf("spotify metadata unavailable (%v), SpotFetch fallback failed (%v), and Deezer conversion is unavailable for playlists", spotifyErr, apiErr)
+	}
+	return "", fmt.Errorf("SpotFetch fallback failed (%v), and Deezer conversion is unavailable for playlists", apiErr)
+}
+
+func shouldTrySpotFetchFallback(err error) bool {
+	if err == nil {
+		return false
+	}
+	if errors.Is(err, ErrNoSpotifyCredentials) {
+		return true
+	}
+
+	errStr := strings.ToLower(err.Error())
+	indicators := []string{
+		"429",
+		"rate",
+		"limit",
+		"403",
+		"forbidden",
+		"401",
+		"unauthorized",
+		"timeout",
+		"connection",
+		"spotify error",
+		"access token",
+		"client token",
+		"eof",
+	}
+
+	for _, indicator := range indicators {
+		if strings.Contains(errStr, indicator) {
+			return true
+		}
+	}
+	return false
 }
 
 func CheckAvailabilityFromDeezerID(deezerTrackID string) (string, error) {

go_backend/extension_providers.go

@@ -1082,16 +1082,18 @@ func tryBuiltInProvider(providerID string, req DownloadRequest) (*DownloadRespon
 		amazonResult, amazonErr := downloadFromAmazon(req)
 		if amazonErr == nil {
 			result = DownloadResult{
-				FilePath:    amazonResult.FilePath,
-				BitDepth:    amazonResult.BitDepth,
-				SampleRate:  amazonResult.SampleRate,
-				Title:       amazonResult.Title,
-				Artist:      amazonResult.Artist,
-				Album:       amazonResult.Album,
-				ReleaseDate: amazonResult.ReleaseDate,
-				TrackNumber: amazonResult.TrackNumber,
-				DiscNumber:  amazonResult.DiscNumber,
-				ISRC:        amazonResult.ISRC,
+				FilePath:      amazonResult.FilePath,
+				BitDepth:      amazonResult.BitDepth,
+				SampleRate:    amazonResult.SampleRate,
+				Title:         amazonResult.Title,
+				Artist:        amazonResult.Artist,
+				Album:         amazonResult.Album,
+				ReleaseDate:   amazonResult.ReleaseDate,
+				TrackNumber:   amazonResult.TrackNumber,
+				DiscNumber:    amazonResult.DiscNumber,
+				ISRC:          amazonResult.ISRC,
+				LyricsLRC:     amazonResult.LyricsLRC,
+				DecryptionKey: amazonResult.DecryptionKey,
 			}
 		}
 		err = amazonErr
@@ -1119,6 +1121,8 @@ func tryBuiltInProvider(providerID string, req DownloadRequest) (*DownloadRespon
 		Genre:            req.Genre,
 		Label:            req.Label,
 		Copyright:        req.Copyright,
+		LyricsLRC:        result.LyricsLRC,
+		DecryptionKey:    result.DecryptionKey,
 	}, nil
 }
 
@@ -1164,16 +1168,30 @@ func (p *ExtensionProviderWrapper) CustomSearch(query string, options map[string
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
-	optionsJSON, _ := json.Marshal(options)
+	if options == nil {
+		options = map[string]interface{}{}
+	}
 
-	script := fmt.Sprintf(`
+	// Avoid embedding user input directly into JS source. Some inputs can trigger
+	// parser/runtime edge cases on specific devices/Goja builds.
+	const queryVar = "__sf_custom_search_query"
+	const optionsVar = "__sf_custom_search_options"
+	global := p.vm.GlobalObject()
+	_ = global.Set(queryVar, query)
+	_ = global.Set(optionsVar, options)
+	defer func() {
+		global.Delete(queryVar)
+		global.Delete(optionsVar)
+	}()
+
+	const script = `
 		(function() {
 			if (typeof extension !== 'undefined' && typeof extension.customSearch === 'function') {
-				return extension.customSearch(%q, %s);
+				return extension.customSearch(__sf_custom_search_query, __sf_custom_search_options);
 			}
 			return null;
 		})()
-	`, query, string(optionsJSON))
+	`
 
 	result, err := RunWithTimeoutAndRecover(p.vm, script, DefaultJSTimeout)
 	if err != nil {
@@ -1358,12 +1376,12 @@ type PostProcessResult struct {
 }
 
 type PostProcessInput struct {
-	Path    string `json:"path,omitempty"`
-	URI     string `json:"uri,omitempty"`
-	Name    string `json:"name,omitempty"`
+	Path     string `json:"path,omitempty"`
+	URI      string `json:"uri,omitempty"`
+	Name     string `json:"name,omitempty"`
 	MimeType string `json:"mime_type,omitempty"`
-	Size    int64  `json:"size,omitempty"`
-	IsSAF   bool   `json:"is_saf,omitempty"`
+	Size     int64  `json:"size,omitempty"`
+	IsSAF    bool   `json:"is_saf,omitempty"`
 }
 
 const PostProcessTimeout = 2 * time.Minute

go_backend/extension_timeout.go

@@ -4,6 +4,7 @@ package gobackend
 import (
 	"context"
 	"fmt"
+	"runtime/debug"
 	"sync"
 	"time"
 
@@ -49,6 +50,7 @@ func RunWithTimeout(vm *goja.Runtime, script string, timeout time.Duration) (goj
 						IsTimeout: true,
 					}}
 				} else {
+					GoLog("[ExtensionRuntime] panic during JS execution: %v\n%s\n", r, string(debug.Stack()))
 					resultCh <- result{nil, fmt.Errorf("panic during execution: %v", r)}
 				}
 			}

go_backend/metadata.go

@@ -475,33 +475,91 @@ func EmbedGenreLabel(filePath string, genre, label string) error {
 }
 
 func ExtractLyrics(filePath string) (string, error) {
+	lower := strings.ToLower(filePath)
+
+	if strings.HasSuffix(lower, ".flac") {
+		return extractLyricsFromFlac(filePath)
+	}
+
+	if strings.HasSuffix(lower, ".mp3") {
+		meta, err := ReadID3Tags(filePath)
+		if err != nil || meta == nil {
+			return "", fmt.Errorf("no lyrics found in file")
+		}
+		if strings.TrimSpace(meta.Lyrics) != "" {
+			return meta.Lyrics, nil
+		}
+		if looksLikeEmbeddedLyrics(meta.Comment) {
+			return meta.Comment, nil
+		}
+		return "", fmt.Errorf("no lyrics found in file")
+	}
+
+	if strings.HasSuffix(lower, ".opus") || strings.HasSuffix(lower, ".ogg") {
+		meta, err := ReadOggVorbisComments(filePath)
+		if err != nil || meta == nil {
+			return "", fmt.Errorf("no lyrics found in file")
+		}
+		if strings.TrimSpace(meta.Lyrics) != "" {
+			return meta.Lyrics, nil
+		}
+		if looksLikeEmbeddedLyrics(meta.Comment) {
+			return meta.Comment, nil
+		}
+		return "", fmt.Errorf("no lyrics found in file")
+	}
+
+	return "", fmt.Errorf("unsupported file format for lyrics extraction")
+}
+
+func extractLyricsFromFlac(filePath string) (string, error) {
 	f, err := flac.ParseFile(filePath)
 	if err != nil {
 		return "", fmt.Errorf("failed to parse FLAC file: %w", err)
 	}
 
 	for _, meta := range f.Meta {
-		if meta.Type == flac.VorbisComment {
-			cmt, err := flacvorbis.ParseFromMetaDataBlock(*meta)
-			if err != nil {
-				continue
-			}
+		if meta.Type != flac.VorbisComment {
+			continue
+		}
 
-			lyrics, err := cmt.Get("LYRICS")
-			if err == nil && len(lyrics) > 0 && lyrics[0] != "" {
-				return lyrics[0], nil
-			}
+		cmt, err := flacvorbis.ParseFromMetaDataBlock(*meta)
+		if err != nil {
+			continue
+		}
 
-			lyrics, err = cmt.Get("UNSYNCEDLYRICS")
-			if err == nil && len(lyrics) > 0 && lyrics[0] != "" {
-				return lyrics[0], nil
-			}
+		lyrics, err := cmt.Get("LYRICS")
+		if err == nil && len(lyrics) > 0 && strings.TrimSpace(lyrics[0]) != "" {
+			return lyrics[0], nil
+		}
+
+		lyrics, err = cmt.Get("UNSYNCEDLYRICS")
+		if err == nil && len(lyrics) > 0 && strings.TrimSpace(lyrics[0]) != "" {
+			return lyrics[0], nil
 		}
 	}
 
 	return "", fmt.Errorf("no lyrics found in file")
 }
 
+func looksLikeEmbeddedLyrics(value string) bool {
+	trimmed := strings.TrimSpace(value)
+	if trimmed == "" {
+		return false
+	}
+
+	lower := strings.ToLower(trimmed)
+	if strings.Contains(lower, "[ar:") || strings.Contains(lower, "[ti:") {
+		return true
+	}
+
+	if strings.Contains(trimmed, "\n") && strings.Contains(trimmed, "[") && strings.Contains(trimmed, "]") {
+		return true
+	}
+
+	return false
+}
+
 type AudioQuality struct {
 	BitDepth     int   `json:"bit_depth"`
 	SampleRate   int   `json:"sample_rate"`

go_backend/qobuz.go

@@ -419,7 +419,7 @@ func extractQobuzDownloadURLFromBody(body []byte) (string, error) {
 func (q *QobuzDownloader) downloadFromJumo(trackID int64, quality string) (string, error) {
 	formatID := mapJumoQuality(quality)
 	region := "US"
-	jumoURL := fmt.Sprintf("https://jumo-dl.pages.dev/file?track_id=%d&format_id=%d&region=%s", trackID, formatID, region)
+	jumoURL := fmt.Sprintf("https://jumo-dl.pages.dev/get?track_id=%d&format_id=%d&region=%s", trackID, formatID, region)
 
 	GoLog("[Qobuz] Trying Jumo API fallback...\n")
 
@@ -428,6 +428,8 @@ func (q *QobuzDownloader) downloadFromJumo(trackID int64, quality string) (strin
 	if err != nil {
 		return "", err
 	}
+	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("Referer", "https://jumo-dl.pages.dev/")
 
 	resp, err := client.Do(req)
 	if err != nil {

go_backend/spotfetch_api.go

@@ -0,0 +1,80 @@
+package gobackend
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+	"time"
+)
+
+const DefaultSpotFetchAPIBaseURL = "https://spotify.afkarxyz.fun/api"
+
+// GetSpotifyDataWithAPI fetches Spotify metadata through SpotFetch-compatible API.
+// This is used as a fallback when direct Spotify API access is blocked/limited.
+func GetSpotifyDataWithAPI(ctx context.Context, spotifyURL, apiBaseURL string) (interface{}, error) {
+	parsed, err := parseSpotifyURI(spotifyURL)
+	if err != nil {
+		return nil, fmt.Errorf("invalid Spotify URL: %w", err)
+	}
+
+	base := strings.TrimSpace(apiBaseURL)
+	if base == "" {
+		base = DefaultSpotFetchAPIBaseURL
+	}
+
+	endpoint := fmt.Sprintf("%s/%s/%s", strings.TrimSuffix(base, "/"), parsed.Type, parsed.ID)
+	req, err := http.NewRequestWithContext(ctx, "GET", endpoint, nil)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create SpotFetch API request: %w", err)
+	}
+	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("Accept", "application/json")
+
+	client := NewHTTPClientWithTimeout(30 * time.Second)
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("SpotFetch API request failed: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("SpotFetch API error: HTTP %d", resp.StatusCode)
+	}
+
+	bodyBytes, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read SpotFetch API response: %w", err)
+	}
+
+	switch parsed.Type {
+	case "track":
+		var trackResp TrackResponse
+		if err := json.Unmarshal(bodyBytes, &trackResp); err != nil {
+			return nil, fmt.Errorf("failed to decode track response: %w", err)
+		}
+		return trackResp, nil
+	case "album":
+		var albumResp AlbumResponsePayload
+		if err := json.Unmarshal(bodyBytes, &albumResp); err != nil {
+			return nil, fmt.Errorf("failed to decode album response: %w", err)
+		}
+		return &albumResp, nil
+	case "playlist":
+		var playlistResp PlaylistResponsePayload
+		if err := json.Unmarshal(bodyBytes, &playlistResp); err != nil {
+			return nil, fmt.Errorf("failed to decode playlist response: %w", err)
+		}
+		return playlistResp, nil
+	case "artist":
+		var artistResp ArtistResponsePayload
+		if err := json.Unmarshal(bodyBytes, &artistResp); err != nil {
+			return nil, fmt.Errorf("failed to decode artist response: %w", err)
+		}
+		return &artistResp, nil
+	default:
+		return nil, fmt.Errorf("unsupported Spotify type: %s", parsed.Type)
+	}
+}