feat: add resolve API with SongLink fallback, fix multi-artist tags (#288), and cleanup

Resolve API (api.zarz.moe):
- Refactor songlink.go: Spotify URLs use resolve API, non-Spotify uses SongLink API
- Add SongLink fallback when resolve API fails for Spotify (two-layer resilience)
- Remove dead code: page parser, XOR-obfuscated keys, legacy helpers

Multi-artist tag fix (#288):
- Add RewriteSplitArtistTags() in Go to rewrite ARTIST/ALBUMARTIST as split Vorbis comments
- Wire method channel handler in Android (MainActivity.kt) and iOS (AppDelegate.swift)
- Add PlatformBridge.rewriteSplitArtistTags() in Dart
- Call native FLAC rewriter after FFmpeg embed when split_vorbis mode is active
- Extract deezerTrackArtistDisplay() helper to use Contributors in album/playlist tracks

Code cleanup:
- Remove unused imports, dead code, and redundant comments across Go and Dart
- Fix build: remove stale getQobuzDebugKey() reference in deezer_download.go

android/app/src/main/kotlin/com/zarz/spotiflac/MainActivity.kt

@@ -2384,6 +2384,41 @@ class MainActivity: FlutterFragmentActivity() {
                             }
                             result.success(response)
                         }
+                        "rewriteSplitArtistTags" -> {
+                            val filePath = call.argument<String>("file_path") ?: ""
+                            val artist = call.argument<String>("artist") ?: ""
+                            val albumArtist = call.argument<String>("album_artist") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                if (filePath.startsWith("content://")) {
+                                    val uri = Uri.parse(filePath)
+                                    val tempPath = copyUriToTemp(uri, ".flac")
+                                        ?: return@withContext errorJson("Failed to copy SAF file to temp")
+                                    try {
+                                        val raw = Gobackend.rewriteSplitArtistTagsExport(tempPath, artist, albumArtist)
+                                        val obj = JSONObject(raw)
+                                        if (!obj.optBoolean("success", false)) {
+                                            return@withContext raw
+                                        }
+
+                                        if (!writeUriFromPath(uri, tempPath)) {
+                                            return@withContext errorJson("Failed to write rewritten tags back to SAF file")
+                                        }
+
+                                        obj.put("file_path", filePath)
+                                        obj.toString()
+                                    } catch (e: Exception) {
+                                        errorJson("Failed to rewrite split artist tags in SAF file: ${e.message}")
+                                    } finally {
+                                        try {
+                                            File(tempPath).delete()
+                                        } catch (_: Exception) {}
+                                    }
+                                } else {
+                                    Gobackend.rewriteSplitArtistTagsExport(filePath, artist, albumArtist)
+                                }
+                            }
+                            result.success(response)
+                        }
                         "cleanupConnections" -> {
                             withContext(Dispatchers.IO) {
                                 Gobackend.cleanupConnections()

go_backend/audio_metadata.go

@@ -338,7 +338,6 @@ func readID3v1(file *os.File) (*AudioMetadata, error) {
 		Year:   strings.TrimRight(string(tag[93:97]), " \x00"),
 	}
 
-	// ID3v1.1 track number (if byte 125 is 0 and byte 126 is not)
 	if tag[125] == 0 && tag[126] != 0 {
 		metadata.TrackNumber = int(tag[126])
 	}
@@ -373,27 +372,23 @@ func extractTextFrame(data []byte) string {
 	}
 }
 
-// extractCommentFrame parses an ID3v2 COMM frame.
-// Format: encoding(1) + language(3) + description(null-terminated) + text
 func extractCommentFrame(data []byte) string {
 	if len(data) < 5 {
 		return ""
 	}
 	encoding := data[0]
-	// skip 3-byte language code
 	rest := data[4:]
 
-	// find null terminator separating description from text
 	var text []byte
 	switch encoding {
-	case 1, 2: // UTF-16 variants use double-null terminator
+	case 1, 2:
 		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
+	default:
 		idx := bytes.IndexByte(rest, 0)
 		if idx >= 0 && idx+1 < len(rest) {
 			text = rest[idx+1:]
@@ -406,33 +401,30 @@ func extractCommentFrame(data []byte) string {
 		return ""
 	}
 
-	// re-prepend encoding byte so extractTextFrame can decode properly
 	framed := make([]byte, 1+len(text))
 	framed[0] = encoding
 	copy(framed[1:], text)
 	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
+	rest := data[4:]
 
 	var text []byte
 	switch encoding {
-	case 1, 2: // UTF-16 variants use double-null terminator
+	case 1, 2:
 		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
+	default:
 		idx := bytes.IndexByte(rest, 0)
 		if idx >= 0 && idx+1 < len(rest) {
 			text = rest[idx+1:]
@@ -451,8 +443,6 @@ func extractLyricsFrame(data []byte) string {
 	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 "", ""
@@ -463,7 +453,7 @@ func extractUserTextFrame(data []byte) (string, string) {
 
 	var descRaw, valueRaw []byte
 	switch encoding {
-	case 1, 2: // UTF-16 variants
+	case 1, 2:
 		for i := 0; i+1 < len(payload); i += 2 {
 			if payload[i] == 0 && payload[i+1] == 0 {
 				descRaw = payload[:i]
@@ -471,7 +461,7 @@ func extractUserTextFrame(data []byte) (string, string) {
 				break
 			}
 		}
-	default: // ISO-8859-1 or UTF-8
+	default:
 		idx := bytes.IndexByte(payload, 0)
 		if idx >= 0 {
 			descRaw = payload[:idx]
@@ -665,7 +655,6 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 
 	file.Seek(audioStart, io.SeekStart)
 
-	// Find first valid MP3 frame sync
 	frameHeader := make([]byte, 4)
 	var frameStart int64 = -1
 	for i := 0; i < 10000; i++ {
@@ -692,8 +681,6 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 	sampleRateIdx := (frameHeader[2] >> 2) & 0x03
 	channelMode := (frameHeader[3] >> 6) & 0x03
 
-	// Sample rate tables: [version][index]
-	// version: 0=MPEG2.5, 1=reserved, 2=MPEG2, 3=MPEG1
 	sampleRates := [][]int{
 		{11025, 12000, 8000},
 		{0, 0, 0},
@@ -704,15 +691,12 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 		quality.SampleRate = sampleRates[version][sampleRateIdx]
 	}
 
-	// Bitrate tables for all MPEG versions and layers
-	// MPEG1 Layer III
 	if version == 3 && layer == 1 {
 		bitrates := []int{0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 0}
 		if bitrateIdx < 16 {
 			quality.Bitrate = bitrates[bitrateIdx] * 1000
 		}
 	}
-	// MPEG2/2.5 Layer III
 	if (version == 0 || version == 2) && layer == 1 {
 		bitrates := []int{0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0}
 		if bitrateIdx < 16 {
@@ -720,14 +704,11 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 		}
 	}
 
-	// Determine samples per frame for duration calculation
 	samplesPerFrame := 1152 // MPEG1 Layer III
 	if version == 0 || version == 2 {
 		samplesPerFrame = 576 // MPEG2/2.5 Layer III
 	}
 
-	// Try to read Xing/VBRI header from the first frame for VBR info
-	// Xing header offset depends on MPEG version and channel mode
 	var xingOffset int
 	if version == 3 { // MPEG1
 		if channelMode == 3 { // Mono
@@ -743,7 +724,6 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 		}
 	}
 
-	// Read enough of the first frame to find Xing/VBRI header
 	xingBuf := make([]byte, 200)
 	file.Seek(frameStart+4, io.SeekStart)
 	n, _ := io.ReadFull(file, xingBuf)
@@ -753,7 +733,6 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 	vbrBytes := int64(0)
 	isVBR := false
 
-	// Check for Xing/Info header
 	if xingOffset+8 <= n {
 		tag := string(xingBuf[xingOffset : xingOffset+4])
 		if tag == "Xing" || tag == "Info" {
@@ -772,7 +751,6 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 		}
 	}
 
-	// Check for VBRI header (always at offset 32 from frame start + 4)
 	if !isVBR && 36+26 <= n {
 		if string(xingBuf[32:36]) == "VBRI" {
 			vbrBytes = int64(binary.BigEndian.Uint32(xingBuf[36+6 : 36+10]))
@@ -784,11 +762,9 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 	}
 
 	if isVBR && vbrFrames > 0 && quality.SampleRate > 0 {
-		// Accurate duration from total frames
 		totalSamples := int64(vbrFrames) * int64(samplesPerFrame)
 		quality.Duration = int(totalSamples / int64(quality.SampleRate))
 
-		// Accurate average bitrate
 		if vbrBytes > 0 && quality.Duration > 0 {
 			quality.Bitrate = int(vbrBytes * 8 / int64(quality.Duration))
 		} else if quality.Duration > 0 {
@@ -796,7 +772,6 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 			quality.Bitrate = int(audioSize * 8 / int64(quality.Duration))
 		}
 	} else if quality.Bitrate > 0 {
-		// CBR fallback: estimate duration from file size and frame bitrate
 		audioSize := fileSize - audioStart - 128 // subtract possible ID3v1 tag
 		if audioSize > 0 {
 			quality.Duration = int(audioSize * 8 / int64(quality.Bitrate))
@@ -983,7 +958,6 @@ func parseVorbisComments(data []byte, metadata *AudioMetadata) {
 	artistValues := make([]string, 0, 1)
 	albumArtistValues := make([]string, 0, 1)
 
-	// Read vendor string length
 	var vendorLen uint32
 	if err := binary.Read(reader, binary.LittleEndian, &vendorLen); err != nil {
 		return
@@ -1012,8 +986,6 @@ func parseVorbisComments(data []byte, metadata *AudioMetadata) {
 		if commentLen > remaining {
 			break
 		}
-		// Large comment entries are typically METADATA_BLOCK_PICTURE.
-		// Skip them so we can continue parsing normal text tags after/before.
 		if commentLen > 512*1024 {
 			reader.Seek(int64(commentLen), io.SeekCurrent)
 			continue
@@ -1123,7 +1095,6 @@ func GetOggQuality(filePath string) (*OggQuality, error) {
 		}
 	}
 
-	// Read granule position from the last Ogg page for accurate duration
 	stat, err := file.Stat()
 	if err != nil {
 		return quality, nil
@@ -1133,7 +1104,6 @@ func GetOggQuality(filePath string) (*OggQuality, error) {
 	granule := readLastOggGranulePosition(file, fileSize)
 	if granule > 0 {
 		if isOpus {
-			// Opus always uses 48kHz granule position internally
 			totalSamples := granule - int64(preSkip)
 			if totalSamples > 0 {
 				durationSec := float64(totalSamples) / 48000.0
@@ -1151,11 +1121,9 @@ func GetOggQuality(filePath string) (*OggQuality, error) {
 		}
 	}
 
-	// Fallback bitrate estimate if duration exists but bitrate couldn't be derived.
 	if quality.Bitrate <= 0 && quality.Duration > 0 {
 		quality.Bitrate = int(fileSize * 8 / int64(quality.Duration))
 	}
-	// Guard against obviously invalid values from corrupted/unreliable granule reads.
 	if quality.Duration > 24*60*60 {
 		quality.Duration = 0
 		quality.Bitrate = 0
@@ -1167,10 +1135,7 @@ func GetOggQuality(filePath string) (*OggQuality, error) {
 	return quality, nil
 }
 
-// readLastOggGranulePosition seeks to the end of the file and scans backwards
-// to find the last Ogg page, then reads its granule position (bytes 6-13).
 func readLastOggGranulePosition(file *os.File, fileSize int64) int64 {
-	// Read the last chunk of the file to find the last OggS sync
 	searchSize := int64(65536)
 	if searchSize > fileSize {
 		searchSize = fileSize
@@ -1194,7 +1159,6 @@ func readLastOggGranulePosition(file *os.File, fileSize int64) int64 {
 		if i+27 > n {
 			continue
 		}
-		// Validate minimal header fields to avoid false positives inside payload bytes.
 		version := buf[i+4]
 		headerType := buf[i+5]
 		if version != 0 || headerType > 0x07 {
@@ -1212,7 +1176,6 @@ func readLastOggGranulePosition(file *os.File, fileSize int64) int64 {
 		if i+headerLen+payloadLen > n {
 			continue
 		}
-		// Granule position is at bytes 6-13 of the Ogg page header (little-endian int64).
 		return int64(binary.LittleEndian.Uint64(buf[i+6 : i+14]))
 	}
 	return 0
@@ -1272,7 +1235,6 @@ func extractMP3CoverArt(filePath string) ([]byte, string, error) {
 		return nil, "", err
 	}
 
-	// Parse frames looking for APIC (Attached Picture)
 	pos := 0
 	var frameIDLen, headerLen int
 	if majorVersion == 2 {
@@ -1303,7 +1265,6 @@ func extractMP3CoverArt(filePath string) ([]byte, string, error) {
 			break
 		}
 
-		// Check for APIC (ID3v2.3/2.4) or PIC (ID3v2.2)
 		if (frameIDLen == 4 && frameID == "APIC") || (frameIDLen == 3 && frameID == "PIC") {
 			frameData := tagData[pos+headerLen : pos+headerLen+frameSize]
 			imageData, mimeType := parseAPICFrame(frameData, majorVersion)

go_backend/cue_parser.go

@@ -11,7 +11,6 @@ import (
 	"strings"
 )
 
-// CueSheet represents a parsed .cue file
 type CueSheet struct {
 	Performer string     `json:"performer"`
 	Title     string     `json:"title"`
@@ -24,7 +23,6 @@ type CueSheet struct {
 	Tracks    []CueTrack `json:"tracks"`
 }
 
-// CueTrack represents a single track in a cue sheet
 type CueTrack struct {
 	Number    int     `json:"number"`
 	Title     string  `json:"title"`
@@ -35,7 +33,6 @@ type CueTrack struct {
 	PreGap    float64 `json:"pre_gap"`    // INDEX 00 in seconds (or -1 if not present)
 }
 
-// CueSplitInfo represents the information needed to split a CUE+audio file
 type CueSplitInfo struct {
 	CuePath   string          `json:"cue_path"`
 	AudioPath string          `json:"audio_path"`
@@ -46,7 +43,6 @@ type CueSplitInfo struct {
 	Tracks    []CueSplitTrack `json:"tracks"`
 }
 
-// CueSplitTrack has the FFmpeg split parameters for a single track
 type CueSplitTrack struct {
 	Number   int     `json:"number"`
 	Title    string  `json:"title"`
@@ -62,7 +58,6 @@ var (
 	reQuoted     = regexp.MustCompile(`"([^"]*)"`)
 )
 
-// ParseCueFile parses a .cue file and returns a CueSheet
 func ParseCueFile(cuePath string) (*CueSheet, error) {
 	f, err := os.Open(cuePath)
 	if err != nil {
@@ -202,7 +197,6 @@ func ParseCueFile(cuePath string) (*CueSheet, error) {
 	return sheet, nil
 }
 
-// parseCueTimestamp converts MM:SS:FF (frames at 75fps) to seconds
 func parseCueTimestamp(ts string) float64 {
 	parts := strings.Split(ts, ":")
 	if len(parts) != 3 {
@@ -216,7 +210,6 @@ func parseCueTimestamp(ts string) float64 {
 	return float64(minutes)*60 + float64(seconds) + float64(frames)/75.0
 }
 
-// formatCueTimestamp converts seconds to HH:MM:SS.mmm format for FFmpeg
 func formatCueTimestamp(seconds float64) string {
 	if seconds < 0 {
 		return "0"
@@ -227,7 +220,6 @@ func formatCueTimestamp(seconds float64) string {
 	return fmt.Sprintf("%02d:%02d:%06.3f", hours, mins, secs)
 }
 
-// unquoteCue removes surrounding quotes from a CUE value
 func unquoteCue(s string) string {
 	s = strings.TrimSpace(s)
 	if matches := reQuoted.FindStringSubmatch(s); len(matches) == 2 {
@@ -236,14 +228,12 @@ func unquoteCue(s string) string {
 	return s
 }
 
-// parseCueFileLine parses the FILE command's filename and type
 func parseCueFileLine(rest string) (string, string) {
 	rest = strings.TrimSpace(rest)
 
 	var filename, ftype string
 
 	if strings.HasPrefix(rest, "\"") {
-		// Quoted filename
 		endQuote := strings.Index(rest[1:], "\"")
 		if endQuote >= 0 {
 			filename = rest[1 : endQuote+1]
@@ -253,7 +243,6 @@ func parseCueFileLine(rest string) (string, string) {
 			filename = rest
 		}
 	} else {
-		// Unquoted filename - last word is the type
 		parts := strings.Fields(rest)
 		if len(parts) >= 2 {
 			ftype = parts[len(parts)-1]
@@ -266,18 +255,14 @@ func parseCueFileLine(rest string) (string, string) {
 	return filename, strings.TrimSpace(ftype)
 }
 
-// ResolveCueAudioPath finds the actual audio file referenced by a .cue sheet.
-// It checks relative to the cue file's directory.
 func ResolveCueAudioPath(cuePath string, cueFileName string) string {
 	cueDir := filepath.Dir(cuePath)
 
-	// 1. Try the exact filename from the .cue
 	candidate := filepath.Join(cueDir, cueFileName)
 	if _, err := os.Stat(candidate); err == nil {
 		return candidate
 	}
 
-	// 2. Try common case variations
 	baseName := strings.TrimSuffix(cueFileName, filepath.Ext(cueFileName))
 	commonExts := []string{".flac", ".wav", ".ape", ".mp3", ".ogg", ".wv", ".m4a"}
 	for _, ext := range commonExts {
@@ -285,14 +270,12 @@ func ResolveCueAudioPath(cuePath string, cueFileName string) string {
 		if _, err := os.Stat(candidate); err == nil {
 			return candidate
 		}
-		// Try uppercase ext
 		candidate = filepath.Join(cueDir, baseName+strings.ToUpper(ext))
 		if _, err := os.Stat(candidate); err == nil {
 			return candidate
 		}
 	}
 
-	// 3. Try to find any audio file with the same base name as the .cue file
 	cueBase := strings.TrimSuffix(filepath.Base(cuePath), filepath.Ext(cuePath))
 	for _, ext := range commonExts {
 		candidate = filepath.Join(cueDir, cueBase+ext)
@@ -301,7 +284,6 @@ func ResolveCueAudioPath(cuePath string, cueFileName string) string {
 		}
 	}
 
-	// 4. If there's only one audio file in the directory, use that
 	entries, err := os.ReadDir(cueDir)
 	if err == nil {
 		audioExts := map[string]bool{
@@ -326,13 +308,9 @@ func ResolveCueAudioPath(cuePath string, cueFileName string) string {
 	return ""
 }
 
-// BuildCueSplitInfo creates the split information from a parsed CUE sheet.
-// This is returned to the Dart side so FFmpeg can perform the splitting.
-// audioDir, if non-empty, overrides the directory for audio file resolution.
 func BuildCueSplitInfo(cuePath string, sheet *CueSheet, audioDir string) (*CueSplitInfo, error) {
 	resolveDir := cuePath
 	if audioDir != "" {
-		// Create a virtual path in audioDir so ResolveCueAudioPath looks there
 		resolveDir = filepath.Join(audioDir, filepath.Base(cuePath))
 	}
 	audioPath := ResolveCueAudioPath(resolveDir, sheet.FileName)
@@ -360,11 +338,9 @@ func BuildCueSplitInfo(cuePath string, sheet *CueSheet, audioDir string) (*CueSp
 			composer = sheet.Composer
 		}
 
-		// End time is the start of the next track, or -1 for the last track
 		endSec := float64(-1)
 		if i+1 < len(sheet.Tracks) {
 			nextTrack := sheet.Tracks[i+1]
-			// Use pre-gap of next track if available, otherwise its start time
 			if nextTrack.PreGap >= 0 {
 				endSec = nextTrack.PreGap
 			} else {
@@ -386,11 +362,6 @@ func BuildCueSplitInfo(cuePath string, sheet *CueSheet, audioDir string) (*CueSp
 	return info, nil
 }
 
-// ParseCueFileJSON parses a .cue file and returns JSON with split info.
-// This is the main entry point called from Dart via the platform bridge.
-// audioDir, if non-empty, overrides the directory used for resolving the
-// referenced audio file (useful when the .cue was copied to a temp dir
-// but the audio still lives in the original location, e.g. SAF).
 func ParseCueFileJSON(cuePath string, audioDir string) (string, error) {
 	sheet, err := ParseCueFile(cuePath)
 	if err != nil {
@@ -410,9 +381,6 @@ func ParseCueFileJSON(cuePath string, audioDir string) (string, error) {
 	return string(jsonBytes), nil
 }
 
-// ScanCueFileForLibrary parses a .cue file and returns multiple LibraryScanResult
-// entries, one per track. This is used by the library scanner to populate the
-// library with individual track entries from a single CUE+FLAC album.
 func ScanCueFileForLibrary(cuePath string, scanTime string) ([]LibraryScanResult, error) {
 	sheet, err := ParseCueFile(cuePath)
 	if err != nil {
@@ -425,13 +393,6 @@ func ScanCueFileForLibrary(cuePath string, scanTime string) ([]LibraryScanResult
 	return scanCueSheetForLibrary(cuePath, sheet, audioPath, "", 0, "", scanTime)
 }
 
-// ScanCueFileForLibraryExt is like ScanCueFileForLibrary but with extra parameters
-// for SAF (Storage Access Framework) scenarios:
-//   - audioDir: if non-empty, overrides the directory used to find the audio file
-//   - virtualPathPrefix: if non-empty, used instead of cuePath as the base for
-//     virtual file paths (e.g. a content:// URI). IDs are also based on this.
-//   - fileModTime: if > 0, used as the FileModTime for all results instead of
-//     stat-ing the cuePath on disk (useful when the real file lives behind SAF)
 func ScanCueFileForLibraryExt(cuePath, audioDir, virtualPathPrefix string, fileModTime int64, scanTime string) ([]LibraryScanResult, error) {
 	return ScanCueFileForLibraryExtWithCoverCacheKey(
 		cuePath,
@@ -483,7 +444,6 @@ func scanCueSheetForLibrary(cuePath string, sheet *CueSheet, audioPath, virtualP
 		return nil, fmt.Errorf("cue sheet is nil for %s", cuePath)
 	}
 
-	// Try to get quality info from the audio file
 	var bitDepth, sampleRate int
 	var totalDurationSec float64
 	audioExt := strings.ToLower(filepath.Ext(audioPath))
@@ -505,7 +465,6 @@ func scanCueSheetForLibrary(cuePath string, sheet *CueSheet, audioPath, virtualP
 		}
 	}
 
-	// Extract cover from audio file for all tracks
 	var coverPath string
 	libraryCoverCacheMu.RLock()
 	coverCacheDir := libraryCoverCacheDir
@@ -522,13 +481,11 @@ func scanCueSheetForLibrary(cuePath string, sheet *CueSheet, audioPath, virtualP
 		}
 	}
 
-	// Determine the base path for virtual paths and IDs
 	pathBase := cuePath
 	if virtualPathPrefix != "" {
 		pathBase = virtualPathPrefix
 	}
 
-	// Determine fileModTime
 	modTime := fileModTime
 	if modTime <= 0 {
 		if info, err := os.Stat(cuePath); err == nil {
@@ -556,7 +513,6 @@ func scanCueSheetForLibrary(cuePath string, sheet *CueSheet, audioPath, virtualP
 			album = "Unknown Album"
 		}
 
-		// Calculate duration for this track
 		var duration int
 		if i+1 < len(sheet.Tracks) {
 			nextStart := sheet.Tracks[i+1].StartTime
@@ -570,9 +526,6 @@ func scanCueSheetForLibrary(cuePath string, sheet *CueSheet, audioPath, virtualP
 
 		id := generateLibraryID(fmt.Sprintf("%s#track%d", pathBase, track.Number))
 
-		// Use a virtual file path that includes the track number to ensure
-		// uniqueness in the database (file_path has a UNIQUE constraint).
-		// Format: /path/to/album.cue#track01 or content://...album.cue#track01
 		virtualFilePath := fmt.Sprintf("%s#track%02d", pathBase, track.Number)
 
 		result := LibraryScanResult{

go_backend/deezer.go

@@ -196,15 +196,22 @@ type deezerAlbumSimple struct {
 	RecordType  string `json:"record_type"`
 }
 
-func (c *DeezerClient) convertTrack(track deezerTrack) TrackMetadata {
-	artistName := track.Artist.Name
+// deezerTrackArtistDisplay returns the display artist string for a track,
+// preferring the Contributors list (comma-joined) when available, falling
+// back to the primary Artist.Name.
+func deezerTrackArtistDisplay(track deezerTrack) string {
 	if len(track.Contributors) > 0 {
 		names := make([]string, len(track.Contributors))
 		for i, a := range track.Contributors {
 			names[i] = a.Name
 		}
-		artistName = strings.Join(names, ", ")
+		return strings.Join(names, ", ")
 	}
+	return track.Artist.Name
+}
+
+func (c *DeezerClient) convertTrack(track deezerTrack) TrackMetadata {
+	artistName := deezerTrackArtistDisplay(track)
 
 	albumImage := track.Album.CoverXL
 	if albumImage == "" {
@@ -641,7 +648,7 @@ func (c *DeezerClient) GetAlbum(ctx context.Context, albumID string) (*AlbumResp
 
 		tracks = append(tracks, AlbumTrackMetadata{
 			SpotifyID:   fmt.Sprintf("deezer:%d", track.ID),
-			Artists:     track.Artist.Name,
+			Artists:     deezerTrackArtistDisplay(track),
 			Name:        track.Title,
 			AlbumName:   album.Title,
 			AlbumArtist: artistName,
@@ -892,7 +899,7 @@ func (c *DeezerClient) GetPlaylist(ctx context.Context, playlistID string) (*Pla
 
 		tracks = append(tracks, AlbumTrackMetadata{
 			SpotifyID:   fmt.Sprintf("deezer:%d", track.ID),
-			Artists:     track.Artist.Name,
+			Artists:     deezerTrackArtistDisplay(track),
 			Name:        track.Title,
 			AlbumName:   track.Album.Title,
 			AlbumArtist: track.Artist.Name,

go_backend/deezer_download.go

@@ -14,7 +14,7 @@ import (
 	"strings"
 )
 
-const deezerMusicDLURL = "https://www.musicdl.me/api/download"
+const deezerMusicDLURL = "https://api.zarz.moe/v1/dzr"
 
 type DeezerDownloadResult struct {
 	FilePath    string
@@ -145,7 +145,6 @@ func (c *DeezerClient) GetMusicDLDownloadURL(deezerTrackURL string) (string, err
 		return "", fmt.Errorf("failed to create MusicDL request: %w", err)
 	}
 	req.Header.Set("Content-Type", "application/json")
-	req.Header.Set("X-Debug-Key", getQobuzDebugKey())
 	req.Header.Set("User-Agent", getRandomUserAgent())
 
 	resp, err := c.httpClient.Do(req)

go_backend/duplicate.go

@@ -25,7 +25,6 @@ var (
 )
 
 func GetISRCIndex(outputDir string) *ISRCIndex {
-	// Fast path: check cache first
 	isrcIndexCacheMu.RLock()
 	idx, exists := isrcIndexCache[outputDir]
 	isrcIndexCacheMu.RUnlock()
@@ -34,13 +33,11 @@ func GetISRCIndex(outputDir string) *ISRCIndex {
 		return idx
 	}
 
-	// Use per-directory mutex to prevent multiple goroutines from building simultaneously
 	buildLock, _ := isrcBuildingMu.LoadOrStore(outputDir, &sync.Mutex{})
 	mu := buildLock.(*sync.Mutex)
 	mu.Lock()
 	defer mu.Unlock()
 
-	// Double-check cache after acquiring lock (another goroutine may have built it)
 	isrcIndexCacheMu.RLock()
 	idx, exists = isrcIndexCache[outputDir]
 	isrcIndexCacheMu.RUnlock()

go_backend/exports.go

@@ -1442,6 +1442,25 @@ func EmbedLyricsToFile(filePath, lyrics string) (string, error) {
 	return string(jsonBytes), nil
 }
 
+// RewriteSplitArtistTagsExport rewrites ARTIST and ALBUMARTIST Vorbis
+// comments in a FLAC file as multiple separate entries (one per artist).
+// Call this after FFmpeg metadata embedding to fix split artist tags,
+// since FFmpeg deduplicates -metadata keys and only keeps the last value.
+func RewriteSplitArtistTagsExport(filePath, artist, albumArtist string) (string, error) {
+	err := RewriteSplitArtistTags(filePath, artist, albumArtist)
+	if err != nil {
+		return errorResponse("Failed to rewrite artist tags: " + err.Error())
+	}
+
+	resp := map[string]interface{}{
+		"success": true,
+		"message": "Split artist tags written successfully",
+	}
+
+	jsonBytes, _ := json.Marshal(resp)
+	return string(jsonBytes), nil
+}
+
 func PreWarmTrackCacheJSON(tracksJSON string) (string, error) {
 	var tracks []struct {
 		ISRC       string `json:"isrc"`

go_backend/extension_providers.go

@@ -1041,9 +1041,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 		}
 	}
 
-	// If key metadata is still missing after extension enrichment, search
-	// configured metadata providers (Spotify/Deezer/Tidal/Qobuz) — same
-	// logic that ReEnrichFile uses.
 	if req.Source != "" && !isBuiltInProvider(strings.ToLower(req.Source)) &&
 		req.TrackName != "" && req.ArtistName != "" &&
 		(req.AlbumName == "" || req.ReleaseDate == "" || req.ISRC == "") {
@@ -1091,7 +1088,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 			GoLog("[DownloadWithExtensionFallback] Metadata provider search failed (non-fatal): %v\n", searchErr)
 		}
 
-		// Try Deezer extended metadata if we have ISRC
 		if req.ISRC != "" &&
 			(req.Genre == "" || req.Label == "" || req.Copyright == "") {
 			ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
@@ -1205,8 +1201,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 					}
 				}
 
-				// Always pass enriched metadata from req so Flutter can
-				// embed it — fills gaps from metadata provider search.
 				if req.AlbumName != "" && resp.Album == "" {
 					resp.Album = req.AlbumName
 				}
@@ -1609,7 +1603,6 @@ func buildOutputPathForExtension(req DownloadRequest, ext *LoadedExtension) stri
 		return buildOutputPath(req)
 	}
 
-	// SAF mode: use extension's data dir as writable temp location
 	tempDir := filepath.Join(ext.DataDir, "downloads")
 	os.MkdirAll(tempDir, 0755)
 	AddAllowedDownloadDir(tempDir)
@@ -2267,7 +2260,6 @@ func (p *ExtensionProviderWrapper) FetchLyrics(trackName, artistName, albumName
 		return nil, fmt.Errorf("failed to parse lyrics result: %w", err)
 	}
 
-	// Convert ExtLyricsResult to LyricsResponse
 	response := &LyricsResponse{
 		SyncType:     extResult.SyncType,
 		Instrumental: extResult.Instrumental,
@@ -2288,7 +2280,6 @@ func (p *ExtensionProviderWrapper) FetchLyrics(trackName, artistName, albumName
 		})
 	}
 
-	// If the extension provided plainLyrics but no lines, parse them as unsynced
 	if len(response.Lines) == 0 && response.PlainLyrics != "" && !response.Instrumental {
 		response.SyncType = "UNSYNCED"
 		for _, line := range strings.Split(response.PlainLyrics, "\n") {
@@ -2316,7 +2307,6 @@ func (m *ExtensionManager) GetLyricsProviders() []*ExtensionProviderWrapper {
 		}
 	}
 
-	// Keep a deterministic order so provider selection is stable across runs.
 	sort.Slice(providers, func(i, j int) bool {
 		return providers[i].extension.ID < providers[j].extension.ID
 	})

go_backend/extension_runtime_auth.go

@@ -201,7 +201,6 @@ func (r *ExtensionRuntime) authGetTokens(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(result)
 }
 
-// Length should be between 43-128 characters (RFC 7636)
 func generatePKCEVerifier(length int) (string, error) {
 	if length < 43 {
 		length = 43
@@ -226,7 +225,6 @@ func generatePKCEVerifier(length int) (string, error) {
 
 func generatePKCEChallenge(verifier string) string {
 	hash := sha256.Sum256([]byte(verifier))
-	// Base64url encode without padding (RFC 7636)
 	return base64.RawURLEncoding.EncodeToString(hash[:])
 }
 
@@ -283,7 +281,6 @@ func (r *ExtensionRuntime) authGetPKCE(call goja.FunctionCall) goja.Value {
 	})
 }
 
-// config: { authUrl, clientId, redirectUri, scope, extraParams }
 func (r *ExtensionRuntime) authStartOAuthWithPKCE(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue(map[string]interface{}{
@@ -388,7 +385,6 @@ func (r *ExtensionRuntime) authStartOAuthWithPKCE(call goja.FunctionCall) goja.V
 	})
 }
 
-// config: { tokenUrl, clientId, redirectUri, code, extraParams }
 func (r *ExtensionRuntime) authExchangeCodeWithPKCE(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue(map[string]interface{}{

go_backend/extension_runtime_polyfills.go

@@ -12,10 +12,6 @@ import (
 	"github.com/dop251/goja"
 )
 
-// These polyfills make porting browser/Node.js libraries easier
-// without compromising sandbox security.
-
-// Returns a Promise-like object with json(), text() methods.
 func (r *ExtensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.createFetchError("URL is required")
@@ -38,7 +34,6 @@ func (r *ExtensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
 				method = strings.ToUpper(m)
 			}
 
-			// Body - support string, object (auto-stringify), or nil
 			if bodyArg, ok := opts["body"]; ok && bodyArg != nil {
 				switch v := bodyArg.(type) {
 				case string:
@@ -197,7 +192,6 @@ func (r *ExtensionRuntime) registerTextEncoderDecoder(vm *goja.Runtime) {
 		})
 
 		encoder.Set("encodeInto", func(call goja.FunctionCall) goja.Value {
-			// Simplified implementation
 			if len(call.Arguments) < 2 {
 				return vm.ToValue(map[string]interface{}{"read": 0, "written": 0})
 			}
@@ -422,7 +416,6 @@ func (r *ExtensionRuntime) registerURLClass(vm *goja.Runtime) {
 	})
 }
 
-// JSON is already built-in to Goja; this ensures a fallback exists.
 func (r *ExtensionRuntime) registerJSONGlobal(vm *goja.Runtime) {
 	jsonScript := `
 		if (typeof JSON === 'undefined') {

go_backend/extension_store.go

@@ -145,7 +145,7 @@ func initExtensionStore(cacheDir string) *extensionStore {
 
 	if globalExtensionStore == nil {
 		globalExtensionStore = &extensionStore{
-			registryURL: "", // No default - user must provide a registry URL
+			registryURL: "",
 			cacheDir:    cacheDir,
 			cacheTTL:    cacheTTL,
 		}
@@ -154,8 +154,6 @@ func initExtensionStore(cacheDir string) *extensionStore {
 	return globalExtensionStore
 }
 
-// SetRegistryURL updates the registry URL and clears the in-memory cache
-// so the next fetch will use the new URL. Disk cache is also cleared.
 func (s *extensionStore) setRegistryURL(registryURL string) {
 	s.cacheMu.Lock()
 	defer s.cacheMu.Unlock()
@@ -168,7 +166,6 @@ func (s *extensionStore) setRegistryURL(registryURL string) {
 	s.cache = nil
 	s.cacheTime = time.Time{}
 
-	// Clear disk cache since it's from a different registry
 	if s.cacheDir != "" {
 		cachePath := filepath.Join(s.cacheDir, cacheFileName)
 		os.Remove(cachePath)
@@ -177,7 +174,6 @@ func (s *extensionStore) setRegistryURL(registryURL string) {
 	LogInfo("ExtensionStore", "Registry URL updated to: %s", registryURL)
 }
 
-// GetRegistryURL returns the currently configured registry URL.
 func (s *extensionStore) getRegistryURL() string {
 	s.cacheMu.RLock()
 	defer s.cacheMu.RUnlock()
@@ -378,32 +374,22 @@ func (s *extensionStore) downloadExtension(extensionID string, destPath string)
 	return nil
 }
 
-// ResolveRegistryURL normalises a user-supplied URL into a direct registry.json URL.
-//
-// Accepted formats:
-//   - https://raw.githubusercontent.com/owner/repo/<branch>/registry.json  → returned as-is
-//   - https://github.com/owner/repo  (with optional trailing path / .git)  → resolved via
-//     the GitHub API to discover the default branch, then converted to the raw URL
-//   - Any other HTTPS URL  → returned as-is (assumed to be a direct link)
 func resolveRegistryURL(input string) (string, error) {
 	input = strings.TrimSpace(input)
 	if input == "" {
 		return "", fmt.Errorf("registry URL is empty")
 	}
 
-	// Already a fully-qualified raw URL – keep it.
 	if strings.Contains(input, "raw.githubusercontent.com") {
 		return input, nil
 	}
 
 	const ghPrefix = "https://github.com/"
 	if !strings.HasPrefix(input, ghPrefix) {
-		// Also accept http:// and upgrade silently.
 		const ghPrefixHTTP = "http://github.com/"
 		if strings.HasPrefix(input, ghPrefixHTTP) {
 			input = "https://github.com/" + input[len(ghPrefixHTTP):]
 		} else {
-			// Not a GitHub URL – return as-is.
 			return input, nil
 		}
 	}
@@ -423,8 +409,6 @@ func resolveRegistryURL(input string) (string, error) {
 	return resolved, nil
 }
 
-// resolveGitHubDefaultBranch calls the GitHub API to discover the repository's
-// default branch.  Falls back to "main" on any error.
 func resolveGitHubDefaultBranch(owner, repo string) string {
 	apiURL := fmt.Sprintf("https://api.github.com/repos/%s/%s", owner, repo)
 	client := NewHTTPClientWithTimeout(10 * time.Second)

go_backend/httputil.go

@@ -66,9 +66,6 @@ var sharedTransport = &http.Transport{
 	DisableCompression:    true,
 }
 
-// metadataTransport is a separate transport for metadata API calls (Deezer, Spotify, SongLink).
-// Isolated from download traffic so that download failures cannot poison
-// the connection pool used by metadata enrichment.
 var metadataTransport = &http.Transport{
 	DialContext: (&net.Dialer{
 		Timeout:   30 * time.Second,
@@ -104,8 +101,6 @@ func NewHTTPClientWithTimeout(timeout time.Duration) *http.Client {
 	}
 }
 
-// NewMetadataHTTPClient creates an HTTP client using the isolated metadata transport.
-// Use this for API calls that should not be affected by download traffic.
 func NewMetadataHTTPClient(timeout time.Duration) *http.Client {
 	return &http.Client{
 		Transport: newCompatibilityTransport(metadataTransport),
@@ -229,7 +224,6 @@ func cloneRequestWithHTTPScheme(req *http.Request, scheme string) (*http.Request
 	return reqCopy, nil
 }
 
-// Also checks for ISP blocking on errors
 func DoRequestWithUserAgent(client *http.Client, req *http.Request) (*http.Response, error) {
 	req.Header.Set("User-Agent", getRandomUserAgent())
 	resp, err := client.Do(req)
@@ -239,7 +233,6 @@ func DoRequestWithUserAgent(client *http.Client, req *http.Request) (*http.Respo
 	return resp, err
 }
 
-// RetryConfig holds configuration for retry logic
 type RetryConfig struct {
 	MaxRetries    int
 	InitialDelay  time.Duration

go_backend/httputil_ios.go

@@ -6,17 +6,10 @@ import (
 	"net/http"
 )
 
-// iOS version: uTLS is not supported on iOS due to cgo DNS resolver issues
-// Fall back to standard HTTP client
-
-// GetCloudflareBypassClient returns the standard HTTP client on iOS
-// uTLS is not available on iOS due to cgo DNS resolver compatibility issues
 func GetCloudflareBypassClient() *http.Client {
 	return sharedClient
 }
 
-// DoRequestWithCloudflareBypass on iOS just uses the standard client
-// uTLS Chrome fingerprint bypass is not available on iOS
 func DoRequestWithCloudflareBypass(req *http.Request) (*http.Response, error) {
 	req.Header.Set("User-Agent", getRandomUserAgent())
 	resp, err := sharedClient.Do(req)

go_backend/httputil_utls.go

@@ -16,8 +16,6 @@ import (
 	"golang.org/x/net/http2"
 )
 
-// uTLS transport that mimics Chrome's TLS fingerprint to bypass Cloudflare
-// Uses HTTP/2 for optimal performance as uTLS works best with HTTP/2
 type utlsTransport struct {
 	dialer       *net.Dialer
 	mu           sync.Mutex
@@ -98,15 +96,10 @@ var cloudflareBypassClient = &http.Client{
 	Timeout:   DefaultTimeout,
 }
 
-// GetCloudflareBypassClient returns an HTTP client that mimics Chrome's TLS fingerprint
-// Use this when requests are blocked by Cloudflare (common when using VPN)
 func GetCloudflareBypassClient() *http.Client {
 	return cloudflareBypassClient
 }
 
-// DoRequestWithCloudflareBypass attempts request with standard client first,
-// then retries with uTLS Chrome fingerprint if Cloudflare blocks it.
-// This is useful when using VPN as Cloudflare detects Go's default TLS fingerprint.
 func DoRequestWithCloudflareBypass(req *http.Request) (*http.Response, error) {
 	req.Header.Set("User-Agent", getRandomUserAgent())
 
@@ -142,7 +135,6 @@ func DoRequestWithCloudflareBypass(req *http.Request) (*http.Response, error) {
 				}
 			}
 
-			// Not Cloudflare, return original response (recreate body)
 			return &http.Response{
 				Status:     resp.Status,
 				StatusCode: resp.StatusCode,

go_backend/idhs.go

@@ -10,8 +10,6 @@ import (
 	"time"
 )
 
-// IDHSClient is a client for I Don't Have Spotify API
-// Used as fallback when SongLink fails or is rate limited
 type IDHSClient struct {
 	client *http.Client
 }
@@ -55,7 +53,6 @@ func NewIDHSClient() *IDHSClient {
 	return globalIDHSClient
 }
 
-// Search converts a music link to links on other platforms
 func (c *IDHSClient) Search(link string, adapters []string) (*IDHSSearchResponse, error) {
 	idhsRateLimiter.WaitForSlot()
 
@@ -109,7 +106,6 @@ func (c *IDHSClient) Search(link string, adapters []string) (*IDHSSearchResponse
 	return &result, nil
 }
 
-// GetAvailabilityFromSpotify checks track availability using IDHS as fallback
 func (c *IDHSClient) GetAvailabilityFromSpotify(spotifyTrackID string) (*TrackAvailability, error) {
 	spotifyURL := fmt.Sprintf("https://open.spotify.com/track/%s", spotifyTrackID)
 

go_backend/library_scan.go

@@ -170,11 +170,9 @@ func ScanLibraryFolder(folderPath string) (string, error) {
 	scanTime := time.Now().UTC().Format(time.RFC3339)
 	errorCount := 0
 
-	// Track audio files referenced by .cue sheets to avoid duplicates
 	cueReferencedAudioFiles := make(map[string]bool)
 	parsedCueFiles := make(map[string]scannedCueFileInfo)
 
-	// First pass: scan .cue files to collect referenced audio paths
 	for _, fileInfo := range audioFileInfos {
 		filePath := fileInfo.path
 		ext := strings.ToLower(filepath.Ext(filePath))
@@ -209,7 +207,6 @@ func ScanLibraryFolder(folderPath string) (string, error) {
 
 		ext := strings.ToLower(filepath.Ext(filePath))
 
-		// Handle .cue files: produce multiple track results
 		if ext == ".cue" {
 			var cueResults []LibraryScanResult
 			cueInfo, ok := parsedCueFiles[filePath]
@@ -827,9 +824,6 @@ func scanLibraryFolderIncrementalWithExistingFiles(folderPath string, existingFi
 	return string(jsonBytes), nil
 }
 
-// ScanLibraryFolderIncremental performs an incremental scan of the library folder
-// existingFilesJSON is a JSON object mapping filePath -> modTime (unix millis)
-// Only files that are new or have changed modification time will be scanned
 func ScanLibraryFolderIncremental(folderPath, existingFilesJSON string) (string, error) {
 	existingFiles := make(map[string]int64)
 	if existingFilesJSON != "" && existingFilesJSON != "{}" {

go_backend/logbuffer.go

@@ -145,13 +145,10 @@ func LogError(tag, format string, args ...interface{}) {
 	GetLogBuffer().Add("ERROR", tag, fmt.Sprintf(format, args...))
 }
 
-// GoLog is a drop-in replacement for fmt.Printf that also logs to buffer
-// It parses the tag from the format string if it starts with [Tag]
 func GoLog(format string, args ...interface{}) {
 	message := fmt.Sprintf(format, args...)
 	message = strings.TrimSuffix(message, "\n")
 
-	// Extract tag from message if present (e.g., "[Tidal] message")
 	tag := "Go"
 	level := "INFO"
 
@@ -163,7 +160,6 @@ func GoLog(format string, args ...interface{}) {
 		}
 	}
 
-	// Determine level from message content
 	msgLower := strings.ToLower(message)
 	if strings.Contains(msgLower, "error") || strings.Contains(msgLower, "failed") {
 		level = "ERROR"

go_backend/lyrics.go

@@ -20,7 +20,6 @@ const (
 	durationToleranceSec = 10.0
 )
 
-// Lyrics provider names (used in settings and cascade ordering)
 const (
 	LyricsProviderLRCLIB     = "lrclib"
 	LyricsProviderNetease    = "netease"
@@ -29,8 +28,6 @@ const (
 	LyricsProviderQQMusic    = "qqmusic"
 )
 
-// DefaultLyricsProviders is the default cascade order for lyrics fetching.
-// LRCLIB first (no proxy dependency), then the others.
 var DefaultLyricsProviders = []string{
 	LyricsProviderLRCLIB,
 	LyricsProviderMusixmatch,
@@ -44,7 +41,6 @@ var (
 	lyricsProviders   []string // ordered list of enabled providers
 )
 
-// LyricsFetchOptions controls optional provider-specific enhancements.
 type LyricsFetchOptions struct {
 	IncludeTranslationNetease  bool   `json:"include_translation_netease"`
 	IncludeRomanizationNetease bool   `json:"include_romanization_netease"`
@@ -64,8 +60,6 @@ var (
 	lyricsFetchOptions   = defaultLyricsFetchOptions
 )
 
-// SetLyricsProviderOrder sets the ordered list of lyrics providers to try.
-// Providers not in the list are disabled. An empty list resets to defaults.
 func SetLyricsProviderOrder(providers []string) {
 	lyricsProvidersMu.Lock()
 	defer lyricsProvidersMu.Unlock()
@@ -532,19 +526,16 @@ func (c *LyricsClient) FetchLyricsAllSources(spotifyID, trackName, artistName st
 	return nil, fmt.Errorf("lyrics not found from any source")
 }
 
-// tryLRCLIB attempts all LRCLIB search strategies (exact match, simplified, search).
 func (c *LyricsClient) tryLRCLIB(primaryArtist, artistName, trackName, simplifiedTrack string, durationSec float64) (*LyricsResponse, error) {
 	var lyrics *LyricsResponse
 	var err error
 
-	// 1. Exact match with primary artist
 	lyrics, err = c.FetchLyricsWithMetadata(primaryArtist, trackName)
 	if err == nil && lyrics != nil && (len(lyrics.Lines) > 0 || lyrics.Instrumental) {
 		lyrics.Source = "LRCLIB"
 		return lyrics, nil
 	}
 
-	// 2. Exact match with full artist name
 	if primaryArtist != artistName {
 		lyrics, err = c.FetchLyricsWithMetadata(artistName, trackName)
 		if err == nil && lyrics != nil && (len(lyrics.Lines) > 0 || lyrics.Instrumental) {
@@ -553,7 +544,6 @@ func (c *LyricsClient) tryLRCLIB(primaryArtist, artistName, trackName, simplifie
 		}
 	}
 
-	// 3. Simplified track name
 	if simplifiedTrack != trackName {
 		lyrics, err = c.FetchLyricsWithMetadata(primaryArtist, simplifiedTrack)
 		if err == nil && lyrics != nil && (len(lyrics.Lines) > 0 || lyrics.Instrumental) {
@@ -562,7 +552,6 @@ func (c *LyricsClient) tryLRCLIB(primaryArtist, artistName, trackName, simplifie
 		}
 	}
 
-	// 4. Search by query
 	query := primaryArtist + " " + trackName
 	lyrics, err = c.FetchLyricsFromLRCLibSearch(query, durationSec)
 	if err == nil && lyrics != nil && (len(lyrics.Lines) > 0 || lyrics.Instrumental) {
@@ -570,7 +559,6 @@ func (c *LyricsClient) tryLRCLIB(primaryArtist, artistName, trackName, simplifie
 		return lyrics, nil
 	}
 
-	// 5. Search with simplified track name
 	if simplifiedTrack != trackName {
 		query = primaryArtist + " " + simplifiedTrack
 		lyrics, err = c.FetchLyricsFromLRCLibSearch(query, durationSec)
@@ -688,8 +676,6 @@ func lyricsHasUsableText(lyrics *LyricsResponse) bool {
 	return false
 }
 
-// detectLyricsErrorPayload extracts human-readable error messages from
-// JSON payloads returned by lyrics proxies when no lyric is available.
 func detectLyricsErrorPayload(raw string) (string, bool) {
 	trimmed := strings.TrimSpace(raw)
 	if trimmed == "" || !strings.HasPrefix(trimmed, "{") {
@@ -814,8 +800,6 @@ func simplifyTrackName(name string) string {
 		return result
 	}
 
-	// Add a loose fallback form for provider queries where punctuation
-	// and separators differ (e.g. "/" vs "_" vs spaces).
 	if loose := normalizeLooseTitle(result); loose != "" {
 		return loose
 	}

go_backend/lyrics_apple.go

@@ -11,8 +11,6 @@ import (
 	"time"
 )
 
-// AppleMusicClient fetches lyrics from Apple Music.
-// Uses Paxsenix endpoints for search and lyrics.
 type AppleMusicClient struct {
 	httpClient *http.Client
 }
@@ -25,7 +23,6 @@ type appleMusicSearchResult struct {
 	Duration   int    `json:"duration"`
 }
 
-// PaxResponse represents the lyrics proxy response for word-by-word / line lyrics
 type paxResponse struct {
 	Type    string      `json:"type"`    // "Syllable" or "Line"
 	Content []paxLyrics `json:"content"` // List of lyric lines
@@ -103,7 +100,6 @@ func selectBestAppleMusicSearchResult(results []appleMusicSearchResult, trackNam
 	return &results[bestIndex]
 }
 
-// SearchSong searches for a song on Apple Music and returns its ID.
 func (c *AppleMusicClient) SearchSong(trackName, artistName string, durationSec float64) (string, error) {
 	query := trackName + " " + artistName
 	if strings.TrimSpace(query) == "" {
@@ -144,7 +140,6 @@ func (c *AppleMusicClient) SearchSong(trackName, artistName string, durationSec
 	return strings.TrimSpace(best.ID), nil
 }
 
-// FetchLyricsByID fetches lyrics from the paxsenix proxy using Apple Music song ID.
 func (c *AppleMusicClient) FetchLyricsByID(songID string) (string, error) {
 	lyricsURL := fmt.Sprintf("https://lyrics.paxsenix.org/apple-music/lyrics?id=%s", songID)
 
@@ -252,7 +247,6 @@ func formatPaxContent(lyricsType string, content []paxLyrics, multiPersonWordByW
 	return strings.TrimSpace(sb.String())
 }
 
-// FetchLyrics searches Apple Music and returns parsed LyricsResponse.
 func (c *AppleMusicClient) FetchLyrics(
 	trackName,
 	artistName string,
@@ -272,10 +266,8 @@ func (c *AppleMusicClient) FetchLyrics(
 		return nil, fmt.Errorf("apple music proxy returned non-lyric payload: %s", errMsg)
 	}
 
-	// Try to parse as pax format (word-by-word or line)
 	lrcText, err := formatPaxLyricsToLRC(rawLyrics, multiPersonWordByWord)
 	if err != nil {
-		// If pax parsing fails, try to parse as direct LRC text
 		lrcText = rawLyrics
 	}
 
@@ -289,7 +281,6 @@ func (c *AppleMusicClient) FetchLyrics(
 		}, nil
 	}
 
-	// Fall back to plain text if no timestamps found
 	resultLines := plainTextLyricsLines(lrcText)
 
 	if len(resultLines) > 0 {

go_backend/lyrics_musixmatch.go

@@ -11,8 +11,6 @@ import (
 	"time"
 )
 
-// MusixmatchClient fetches lyrics from Musixmatch via a proxy server.
-// The proxy handles Musixmatch authentication internally.
 type MusixmatchClient struct {
 	httpClient *http.Client
 	baseURL    string
@@ -114,7 +112,6 @@ func (c *MusixmatchClient) fetchLyricsPayload(trackName, artistName string, dura
 	return "", fmt.Errorf("failed to decode musixmatch response")
 }
 
-// FetchLyricsInLanguage retrieves lyrics from Musixmatch for a specific language code.
 func (c *MusixmatchClient) FetchLyricsInLanguage(trackName, artistName string, durationSec float64, language string) (*LyricsResponse, error) {
 	lang := strings.ToLower(strings.TrimSpace(language))
 	if lang == "" {
@@ -151,7 +148,6 @@ func (c *MusixmatchClient) FetchLyricsInLanguage(trackName, artistName string, d
 	return nil, fmt.Errorf("no lyrics found on musixmatch for language %s", lang)
 }
 
-// FetchLyrics searches Musixmatch and returns parsed LyricsResponse.
 func (c *MusixmatchClient) FetchLyrics(trackName, artistName string, durationSec float64, preferredLanguage string) (*LyricsResponse, error) {
 	if preferred := strings.ToLower(strings.TrimSpace(preferredLanguage)); preferred != "" {
 		localized, localizedErr := c.FetchLyricsInLanguage(trackName, artistName, durationSec, preferred)

go_backend/lyrics_netease.go

@@ -9,7 +9,6 @@ import (
 	"time"
 )
 
-// NeteaseClient fetches lyrics through Paxsenix's NetEase endpoints.
 type NeteaseClient struct {
 	httpClient *http.Client
 }
@@ -51,7 +50,6 @@ func NewNeteaseClient() *NeteaseClient {
 	}
 }
 
-// SearchSong searches for a song on Netease and returns the song ID.
 func (c *NeteaseClient) SearchSong(trackName, artistName string) (int64, error) {
 	query := trackName + " " + artistName
 	if strings.TrimSpace(query) == "" {
@@ -96,7 +94,6 @@ func (c *NeteaseClient) SearchSong(trackName, artistName string) (int64, error)
 	return searchResp.Result.Songs[0].ID, nil
 }
 
-// FetchLyricsByID fetches synced lyrics for a given Netease song ID.
 func (c *NeteaseClient) FetchLyricsByID(songID int64, includeTranslation, includeRomanization bool) (string, error) {
 	lyricsURL := "https://lyrics.paxsenix.org/netease/lyrics"
 	params := url.Values{}
@@ -146,7 +143,6 @@ func (c *NeteaseClient) FetchLyricsByID(songID int64, includeTranslation, includ
 	return lyric, nil
 }
 
-// FetchLyrics searches for a track and returns parsed LyricsResponse.
 func (c *NeteaseClient) FetchLyrics(
 	trackName,
 	artistName string,
@@ -166,7 +162,6 @@ func (c *NeteaseClient) FetchLyrics(
 
 	lines := parseSyncedLyrics(lrcText)
 	if len(lines) == 0 {
-		// May be plain text lyrics without timestamps
 		plainLines := strings.Split(lrcText, "\n")
 		for _, line := range plainLines {
 			trimmed := strings.TrimSpace(line)

go_backend/lyrics_qqmusic.go

@@ -10,8 +10,6 @@ import (
 	"time"
 )
 
-// QQMusicClient fetches lyrics from QQ Music.
-// Uses Paxsenix metadata lookup for lyrics.
 type QQMusicClient struct {
 	httpClient *http.Client
 }
@@ -34,7 +32,6 @@ func NewQQMusicClient() *QQMusicClient {
 	}
 }
 
-// fetchLyricsByMetadata asks Paxsenix to resolve and return QQ lyrics using track metadata.
 func (c *QQMusicClient) fetchLyricsByMetadata(trackName, artistName string, durationSec float64) (string, error) {
 	payload := qqLyricsMetadataRequest{
 		Artist: []string{artistName},
@@ -93,7 +90,6 @@ func formatQQLyricsMetadataToLRC(rawJSON string, multiPersonWordByWord bool) (st
 	return formatPaxContent("Syllable", response.Lyrics, multiPersonWordByWord), nil
 }
 
-// FetchLyrics searches QQ Music and returns parsed LyricsResponse.
 func (c *QQMusicClient) FetchLyrics(
 	trackName,
 	artistName string,

go_backend/metadata.go

@@ -431,6 +431,52 @@ func setArtistComments(cmt *flacvorbis.MetaDataBlockVorbisComment, key, value, m
 	}
 }
 
+// RewriteSplitArtistTags opens a FLAC file and rewrites the ARTIST and
+// ALBUMARTIST Vorbis comments as multiple separate entries (one per artist).
+// This is needed because FFmpeg's -metadata flag deduplicates keys, so only
+// the last value survives when multiple -metadata ARTIST=X flags are used.
+// The native go-flac writer correctly handles multiple Vorbis comments.
+func RewriteSplitArtistTags(filePath, artist, albumArtist string) error {
+	if !shouldSplitVorbisArtistTags(artistTagModeSplitVorbis) {
+		return nil
+	}
+
+	f, err := flac.ParseFile(filePath)
+	if err != nil {
+		return fmt.Errorf("failed to parse FLAC file: %w", err)
+	}
+
+	var cmtIdx int = -1
+	var cmt *flacvorbis.MetaDataBlockVorbisComment
+
+	for idx, meta := range f.Meta {
+		if meta.Type == flac.VorbisComment {
+			cmtIdx = idx
+			cmt, err = flacvorbis.ParseFromMetaDataBlock(*meta)
+			if err != nil {
+				return fmt.Errorf("failed to parse vorbis comment: %w", err)
+			}
+			break
+		}
+	}
+
+	if cmt == nil {
+		cmt = flacvorbis.New()
+	}
+
+	setArtistComments(cmt, "ARTIST", artist, artistTagModeSplitVorbis)
+	setArtistComments(cmt, "ALBUMARTIST", albumArtist, artistTagModeSplitVorbis)
+
+	cmtMeta := cmt.Marshal()
+	if cmtIdx >= 0 {
+		f.Meta[cmtIdx] = &cmtMeta
+	} else {
+		f.Meta = append(f.Meta, &cmtMeta)
+	}
+
+	return f.Save(filePath)
+}
+
 func removeCommentKey(cmt *flacvorbis.MetaDataBlockVorbisComment, key string) {
 	keyUpper := strings.ToUpper(key)
 	for i := len(cmt.Comments) - 1; i >= 0; i-- {

go_backend/qobuz.go

@@ -53,26 +53,17 @@ const (
 	qobuzTrackOpenBaseURL   = "https://open.qobuz.com/track/"
 	qobuzTrackPlayBaseURL   = "https://play.qobuz.com/track/"
 	qobuzStoreBaseURL       = "https://www.qobuz.com/us-en"
-	qobuzDownloadAPIURL     = "https://dl.musicdl.me/qobuz/download"
+	qobuzDownloadAPIURL     = "https://api.zarz.moe/v1/qbz"
 	qobuzDabMusicAPIURL     = "https://dabmusic.xyz/api/stream?trackId="
 	qobuzDeebAPIURL         = "https://dab.yeet.su/api/stream?trackId="
 	qobuzAfkarAPIURL        = "https://qbz.afkarxyz.qzz.io/api/track/"
 	qobuzSquidAPIURL        = "https://qobuz.squid.wtf/api/download-music?country=US&track_id="
-	qobuzDebugKeyXORMask    = byte(0x5A)
 )
 
 var qobuzStoreTrackIDRegex = regexp.MustCompile(`/v4/ajax/popin-add-cart/track/([0-9]+)`)
 var qobuzArtistAlbumIDRegex = regexp.MustCompile(`data-itemtype="album"\s+data-itemId="([A-Za-z0-9]+)"`)
 var qobuzLocaleSegmentRegex = regexp.MustCompile(`^[a-z]{2}-[a-z]{2}$`)
 
-var qobuzDebugKeyObfuscated = []byte{
-	0x69, 0x3b, 0x38, 0x3e, 0x36, 0x37, 0x35, 0x2f, 0x36, 0x3b,
-	0x33, 0x29, 0x2e, 0x32, 0x3f, 0x3d, 0x35, 0x3b, 0x2e, 0x3b,
-	0x34, 0x3e, 0x34, 0x35, 0x35, 0x34, 0x3f, 0x39, 0x35, 0x37,
-	0x3f, 0x29, 0x3f, 0x2c, 0x3f, 0x34, 0x39, 0x36, 0x35, 0x29,
-	0x3f,
-}
-
 type QobuzTrack struct {
 	ID                  int64   `json:"id"`
 	Title               string  `json:"title"`
@@ -1216,14 +1207,6 @@ func mapQobuzQualityCodeToAPI(qualityCode string) string {
 	}
 }
 
-func getQobuzDebugKey() string {
-	decoded := make([]byte, len(qobuzDebugKeyObfuscated))
-	for i, b := range qobuzDebugKeyObfuscated {
-		decoded[i] = b ^ qobuzDebugKeyXORMask
-	}
-	return string(decoded)
-}
-
 func (q *QobuzDownloader) SearchTrackByISRC(isrc string) (*QobuzTrack, error) {
 	candidates, err := q.searchQobuzTracksWithFallback(isrc, 50)
 	if err != nil {

go_backend/qobuz_test.go

@@ -201,18 +201,6 @@ func TestNormalizeQobuzQualityCode(t *testing.T) {
 	}
 }
 
-func TestGetQobuzDebugKey(t *testing.T) {
-	got := getQobuzDebugKey()
-	if len(got) != len(qobuzDebugKeyObfuscated) {
-		t.Fatalf("unexpected debug key length: %d", len(got))
-	}
-	for i := range got {
-		if got[i]^qobuzDebugKeyXORMask != qobuzDebugKeyObfuscated[i] {
-			t.Fatalf("unexpected debug key reconstruction at index %d", i)
-		}
-	}
-}
-
 func TestBuildQobuzMusicDLPayloadUsesOpenTrackURL(t *testing.T) {
 	payloadBytes, err := buildQobuzMusicDLPayload(374610875, "7")
 	if err != nil {

go_backend/romaji.go

@@ -16,16 +16,13 @@ var hiraganaToRomaji = map[rune]string{
 	'や': "ya", 'ゆ': "yu", 'よ': "yo",
 	'ら': "ra", 'り': "ri", 'る': "ru", 'れ': "re", 'ろ': "ro",
 	'わ': "wa", 'を': "wo", 'ん': "n",
-	// Dakuten (voiced)
 	'が': "ga", 'ぎ': "gi", 'ぐ': "gu", 'げ': "ge", 'ご': "go",
 	'ざ': "za", 'じ': "ji", 'ず': "zu", 'ぜ': "ze", 'ぞ': "zo",
 	'だ': "da", 'ぢ': "ji", 'づ': "zu", 'で': "de", 'ど': "do",
 	'ば': "ba", 'び': "bi", 'ぶ': "bu", 'べ': "be", 'ぼ': "bo",
-	// Handakuten (semi-voiced)
 	'ぱ': "pa", 'ぴ': "pi", 'ぷ': "pu", 'ぺ': "pe", 'ぽ': "po",
-	// Small characters
 	'ゃ': "ya", 'ゅ': "yu", 'ょ': "yo",
-	'っ': "", // Double consonant marker
+	'っ': "",
 	'ぁ': "a", 'ぃ': "i", 'ぅ': "u", 'ぇ': "e", 'ぉ': "o",
 }
 
@@ -40,19 +37,15 @@ var katakanaToRomaji = map[rune]string{
 	'ヤ': "ya", 'ユ': "yu", 'ヨ': "yo",
 	'ラ': "ra", 'リ': "ri", 'ル': "ru", 'レ': "re", 'ロ': "ro",
 	'ワ': "wa", 'ヲ': "wo", 'ン': "n",
-	// Dakuten (voiced)
 	'ガ': "ga", 'ギ': "gi", 'グ': "gu", 'ゲ': "ge", 'ゴ': "go",
 	'ザ': "za", 'ジ': "ji", 'ズ': "zu", 'ゼ': "ze", 'ゾ': "zo",
 	'ダ': "da", 'ヂ': "ji", 'ヅ': "zu", 'デ': "de", 'ド': "do",
 	'バ': "ba", 'ビ': "bi", 'ブ': "bu", 'ベ': "be", 'ボ': "bo",
-	// Handakuten (semi-voiced)
 	'パ': "pa", 'ピ': "pi", 'プ': "pu", 'ペ': "pe", 'ポ': "po",
-	// Small characters
 	'ャ': "ya", 'ュ': "yu", 'ョ': "yo",
-	'ッ': "", // Double consonant marker
+	'ッ': "",
 	'ァ': "a", 'ィ': "i", 'ゥ': "u", 'ェ': "e", 'ォ': "o",
-	// Extended katakana
-	'ー': "", // Long vowel mark
+	'ー': "",
 	'ヴ': "vu",
 }
 
@@ -82,7 +75,6 @@ var combinationKatakana = map[string]string{
 	"ジャ": "ja", "ジュ": "ju", "ジョ": "jo",
 	"ビャ": "bya", "ビュ": "byu", "ビョ": "byo",
 	"ピャ": "pya", "ピュ": "pyu", "ピョ": "pyo",
-	// Extended combinations
 	"ティ": "ti", "ディ": "di", "トゥ": "tu", "ドゥ": "du",
 	"ファ": "fa", "フィ": "fi", "フェ": "fe", "フォ": "fo",
 	"ウィ": "wi", "ウェ": "we", "ウォ": "wo",
@@ -120,7 +112,6 @@ func JapaneseToRomaji(text string) string {
 	i := 0
 
 	for i < len(runes) {
-		// Check for っ/ッ (double consonant)
 		if i < len(runes)-1 && (runes[i] == 'っ' || runes[i] == 'ッ') {
 			nextRomaji := ""
 			if romaji, ok := hiraganaToRomaji[runes[i+1]]; ok {
@@ -129,13 +120,12 @@ func JapaneseToRomaji(text string) string {
 				nextRomaji = romaji
 			}
 			if len(nextRomaji) > 0 {
-				result.WriteByte(nextRomaji[0]) // Double the first consonant
+				result.WriteByte(nextRomaji[0])
 			}
 			i++
 			continue
 		}
 
-		// Check for two-character combinations
 		if i < len(runes)-1 {
 			combo := string(runes[i : i+2])
 			if romaji, ok := combinationHiragana[combo]; ok {
@@ -150,17 +140,14 @@ func JapaneseToRomaji(text string) string {
 			}
 		}
 
-		// Single character conversion
 		r := runes[i]
 		if romaji, ok := hiraganaToRomaji[r]; ok {
 			result.WriteString(romaji)
 		} else if romaji, ok := katakanaToRomaji[r]; ok {
 			result.WriteString(romaji)
 		} else if isKanji(r) {
-			// Keep kanji as-is (would need dictionary for proper conversion)
 			result.WriteRune(r)
 		} else {
-			// Keep other characters (punctuation, spaces, etc.)
 			result.WriteRune(r)
 		}
 		i++

go_backend/songlink.go

@@ -87,38 +87,184 @@ func GetSongLinkRegion() string {
 	return region
 }
 
+const resolveAPIURL = "https://api.zarz.moe/v1/resolve"
+
 func songLinkBaseURL() string {
-	opts := GetNetworkCompatibilityOptions()
-	if opts.AllowHTTP {
-		return "http://api.song.link/v1-alpha.1/links"
-	}
 	return "https://api.song.link/v1-alpha.1/links"
 }
 
-func buildSongLinkURLFromTarget(targetURL string, userCountry string) string {
-	if userCountry == "" {
-		userCountry = GetSongLinkRegion()
+// resolveTrackPlatforms resolves a music URL to all platforms.
+// Spotify URLs use the resolve API; if that fails, falls back to SongLink.
+// All other URLs go directly to SongLink.
+func (s *SongLinkClient) resolveTrackPlatforms(inputURL string) (map[string]songLinkPlatformLink, error) {
+	if isSpotifyURL(inputURL) {
+		payload, err := json.Marshal(map[string]string{"url": inputURL})
+		if err != nil {
+			return nil, fmt.Errorf("failed to encode resolve request: %w", err)
+		}
+		links, err := s.doResolveRequest(payload)
+		if err == nil {
+			return links, nil
+		}
+		GoLog("[SongLink] Resolve proxy failed for %s: %v, falling back to SongLink", inputURL, err)
+		return s.songLinkByTargetURL(inputURL)
 	}
-	apiURL := fmt.Sprintf("%s?url=%s", songLinkBaseURL(), url.QueryEscape(targetURL))
-	if userCountry != "" {
-		apiURL = fmt.Sprintf("%s&userCountry=%s", apiURL, url.QueryEscape(userCountry))
-	}
-	return apiURL
+	return s.songLinkByTargetURL(inputURL)
 }
 
-func buildSongLinkURLByPlatform(platform, entityType, entityID, userCountry string) string {
-	if userCountry == "" {
-		userCountry = GetSongLinkRegion()
+// resolveTrackPlatformsByPlatform resolves using platform + type + id.
+// Spotify uses the resolve API with SongLink fallback; all other platforms use SongLink directly.
+func (s *SongLinkClient) resolveTrackPlatformsByPlatform(platform, entityType, entityID string) (map[string]songLinkPlatformLink, error) {
+	if strings.EqualFold(platform, "spotify") {
+		payload, err := json.Marshal(map[string]string{
+			"platform": platform,
+			"type":     entityType,
+			"id":       entityID,
+		})
+		if err != nil {
+			return nil, fmt.Errorf("failed to encode resolve request: %w", err)
+		}
+		links, err := s.doResolveRequest(payload)
+		if err == nil {
+			return links, nil
+		}
+		GoLog("[SongLink] Resolve proxy failed for %s/%s/%s: %v, falling back to SongLink", platform, entityType, entityID, err)
+		return s.songLinkByPlatform(platform, entityType, entityID)
 	}
-	apiURL := fmt.Sprintf("%s?platform=%s&type=%s&id=%s",
+	return s.songLinkByPlatform(platform, entityType, entityID)
+}
+
+func isSpotifyURL(u string) bool {
+	lower := strings.ToLower(u)
+	return strings.Contains(lower, "spotify.com/") || strings.Contains(lower, "spotify:")
+}
+
+// doResolveRequest sends a JSON payload to the resolve API (api.zarz.moe)
+// and parses the response into a platform link map.
+func (s *SongLinkClient) doResolveRequest(payload []byte) (map[string]songLinkPlatformLink, error) {
+	req, err := http.NewRequest("POST", resolveAPIURL, bytes.NewReader(payload))
+	if err != nil {
+		return nil, fmt.Errorf("failed to create resolve request: %w", err)
+	}
+	req.Header.Set("Content-Type", "application/json")
+
+	resp, err := s.client.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("resolve API request failed: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != 200 {
+		return nil, fmt.Errorf("resolve API returned status %d", resp.StatusCode)
+	}
+
+	body, err := ReadResponseBody(resp)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read resolve response: %w", err)
+	}
+
+	var resolveResp struct {
+		Success  bool              `json:"success"`
+		ISRC     string            `json:"isrc"`
+		SongUrls map[string]string `json:"songUrls"`
+	}
+	if err := json.Unmarshal(body, &resolveResp); err != nil {
+		return nil, fmt.Errorf("failed to decode resolve response: %w", err)
+	}
+	if !resolveResp.Success {
+		return nil, fmt.Errorf("resolve API returned success=false")
+	}
+
+	// Map resolve API keys to SongLink-compatible platform keys
+	keyMap := map[string]string{
+		"Spotify":      "spotify",
+		"Deezer":       "deezer",
+		"Tidal":        "tidal",
+		"YouTubeMusic": "youtubeMusic",
+		"YouTube":      "youtube",
+		"AmazonMusic":  "amazonMusic",
+		"Qobuz":        "qobuz",
+		"AppleMusic":   "appleMusic",
+	}
+
+	links := make(map[string]songLinkPlatformLink)
+	for resolveKey, platformKey := range keyMap {
+		if u, ok := resolveResp.SongUrls[resolveKey]; ok && strings.TrimSpace(u) != "" {
+			links[platformKey] = songLinkPlatformLink{URL: strings.TrimSpace(u)}
+		}
+	}
+
+	if len(links) == 0 {
+		return nil, fmt.Errorf("resolve API returned no platform links")
+	}
+
+	return links, nil
+}
+
+// songLinkByTargetURL calls the SongLink API with a target URL (for non-Spotify URLs).
+func (s *SongLinkClient) songLinkByTargetURL(targetURL string) (map[string]songLinkPlatformLink, error) {
+	songLinkRateLimiter.WaitForSlot()
+
+	apiURL := fmt.Sprintf("%s?url=%s&userCountry=%s",
+		songLinkBaseURL(),
+		url.QueryEscape(targetURL),
+		url.QueryEscape(GetSongLinkRegion()))
+
+	return s.doSongLinkRequest(apiURL)
+}
+
+// songLinkByPlatform calls the SongLink API with platform + type + id (for non-Spotify platforms).
+func (s *SongLinkClient) songLinkByPlatform(platform, entityType, entityID string) (map[string]songLinkPlatformLink, error) {
+	songLinkRateLimiter.WaitForSlot()
+
+	apiURL := fmt.Sprintf("%s?platform=%s&type=%s&id=%s&userCountry=%s",
 		songLinkBaseURL(),
 		url.QueryEscape(platform),
 		url.QueryEscape(entityType),
-		url.QueryEscape(entityID))
-	if userCountry != "" {
-		apiURL = fmt.Sprintf("%s&userCountry=%s", apiURL, url.QueryEscape(userCountry))
+		url.QueryEscape(entityID),
+		url.QueryEscape(GetSongLinkRegion()))
+
+	return s.doSongLinkRequest(apiURL)
+}
+
+// doSongLinkRequest calls the SongLink API and parses the response.
+func (s *SongLinkClient) doSongLinkRequest(apiURL string) (map[string]songLinkPlatformLink, error) {
+	req, err := http.NewRequest("GET", apiURL, nil)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create SongLink request: %w", err)
 	}
-	return apiURL
+
+	retryConfig := songLinkRetryConfig()
+	resp, err := DoRequestWithRetry(s.client, req, retryConfig)
+	if err != nil {
+		return nil, fmt.Errorf("SongLink request failed: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode == 429 {
+		return nil, fmt.Errorf("SongLink rate limit exceeded")
+	}
+	if resp.StatusCode != 200 {
+		return nil, fmt.Errorf("SongLink returned status %d", resp.StatusCode)
+	}
+
+	body, err := ReadResponseBody(resp)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read SongLink response: %w", err)
+	}
+
+	var songLinkResp struct {
+		LinksByPlatform map[string]songLinkPlatformLink `json:"linksByPlatform"`
+	}
+	if err := json.Unmarshal(body, &songLinkResp); err != nil {
+		return nil, fmt.Errorf("failed to decode SongLink response: %w", err)
+	}
+
+	if len(songLinkResp.LinksByPlatform) == 0 {
+		return nil, fmt.Errorf("SongLink returned no platform links")
+	}
+
+	return songLinkResp.LinksByPlatform, nil
 }
 
 func (s *SongLinkClient) CheckTrackAvailability(spotifyTrackID string, isrc string) (*TrackAvailability, error) {
@@ -136,145 +282,12 @@ func (s *SongLinkClient) CheckTrackAvailability(spotifyTrackID string, isrc stri
 }
 
 func (s *SongLinkClient) checkTrackAvailabilityFromSpotify(spotifyTrackID string) (*TrackAvailability, error) {
-	availability, pageErr := s.checkTrackAvailabilityFromSpotifyPage(spotifyTrackID)
-	if pageErr == nil {
-		return availability, nil
-	}
-
-	if !songLinkRateLimiter.TryAcquire() {
-		return nil, fmt.Errorf("song.link page lookup failed: %w (SongLink local rate limit exceeded)", pageErr)
-	}
-
 	spotifyURL := fmt.Sprintf("https://open.spotify.com/track/%s", spotifyTrackID)
-	apiURL := buildSongLinkURLFromTarget(spotifyURL, "")
-
-	req, err := http.NewRequest("GET", apiURL, nil)
+	links, err := s.resolveTrackPlatforms(spotifyURL)
 	if err != nil {
-		return nil, fmt.Errorf("failed to create request: %w", err)
+		return nil, fmt.Errorf("resolve proxy failed for Spotify %s: %w", spotifyTrackID, err)
 	}
-
-	retryConfig := songLinkRetryConfig()
-	resp, err := DoRequestWithRetry(s.client, req, retryConfig)
-	if err != nil {
-		return nil, fmt.Errorf("song.link page lookup failed: %w; SongLink API lookup failed: %w", pageErr, err)
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode == 400 {
-		return nil, fmt.Errorf("track not found on SongLink (invalid Spotify ID or track unavailable)")
-	}
-	if resp.StatusCode == 404 {
-		return nil, fmt.Errorf("track not found on any streaming platform")
-	}
-	if resp.StatusCode == 429 {
-		return nil, fmt.Errorf("song.link page lookup failed: %w; SongLink API rate limit exceeded", pageErr)
-	}
-	if resp.StatusCode != 200 {
-		return nil, fmt.Errorf("song.link page lookup failed: %w; SongLink API returned status %d", pageErr, resp.StatusCode)
-	}
-
-	body, err := ReadResponseBody(resp)
-	if err != nil {
-		return nil, fmt.Errorf("failed to read response: %w", err)
-	}
-
-	var songLinkResp struct {
-		LinksByPlatform map[string]songLinkPlatformLink `json:"linksByPlatform"`
-	}
-
-	if err := json.Unmarshal(body, &songLinkResp); err != nil {
-		return nil, fmt.Errorf("failed to decode response: %w", err)
-	}
-
-	LogWarn("SongLink", "Spotify %s resolved via SongLink API after song.link page failure: %v", spotifyTrackID, pageErr)
-	return buildTrackAvailabilityFromSongLinkLinks(spotifyTrackID, songLinkResp.LinksByPlatform), nil
-}
-
-func (s *SongLinkClient) checkTrackAvailabilityFromSpotifyPage(spotifyTrackID string) (*TrackAvailability, error) {
-	pageURL := fmt.Sprintf("https://song.link/s/%s", spotifyTrackID)
-	req, err := http.NewRequest("GET", pageURL, nil)
-	if err != nil {
-		return nil, fmt.Errorf("failed to create song.link page request: %w", err)
-	}
-
-	req.Header.Set("Accept", "text/html,application/xhtml+xml")
-	req.Header.Set("User-Agent", getRandomUserAgent())
-
-	resp, err := s.client.Do(req)
-	if err != nil {
-		return nil, fmt.Errorf("failed to fetch song.link page: %w", err)
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode == 404 {
-		return nil, fmt.Errorf("track not found on song.link page")
-	}
-	if resp.StatusCode != 200 {
-		return nil, fmt.Errorf("song.link page returned status %d", resp.StatusCode)
-	}
-
-	body, err := ReadResponseBody(resp)
-	if err != nil {
-		return nil, fmt.Errorf("failed to read song.link page: %w", err)
-	}
-
-	nextDataJSON, err := extractSongLinkNextDataJSON(body)
-	if err != nil {
-		return nil, err
-	}
-
-	var pageData struct {
-		Props struct {
-			PageProps struct {
-				PageData struct {
-					Sections []struct {
-						Links []struct {
-							Platform string `json:"platform"`
-							URL      string `json:"url"`
-							Show     bool   `json:"show"`
-						} `json:"links"`
-					} `json:"sections"`
-				} `json:"pageData"`
-			} `json:"pageProps"`
-		} `json:"props"`
-	}
-	if err := json.Unmarshal(nextDataJSON, &pageData); err != nil {
-		return nil, fmt.Errorf("failed to decode song.link page data: %w", err)
-	}
-
-	linksByPlatform := make(map[string]songLinkPlatformLink)
-	for _, section := range pageData.Props.PageProps.PageData.Sections {
-		for _, link := range section.Links {
-			if !link.Show || strings.TrimSpace(link.URL) == "" {
-				continue
-			}
-			linksByPlatform[link.Platform] = songLinkPlatformLink{URL: link.URL}
-		}
-	}
-
-	if len(linksByPlatform) == 0 {
-		return nil, fmt.Errorf("song.link page contained no usable platform links")
-	}
-
-	return buildTrackAvailabilityFromSongLinkLinks(spotifyTrackID, linksByPlatform), nil
-}
-
-func extractSongLinkNextDataJSON(body []byte) ([]byte, error) {
-	const startMarker = `<script id="__NEXT_DATA__" type="application/json">`
-	const endMarker = `</script>`
-
-	start := bytes.Index(body, []byte(startMarker))
-	if start < 0 {
-		return nil, fmt.Errorf("song.link page missing __NEXT_DATA__")
-	}
-	start += len(startMarker)
-
-	end := bytes.Index(body[start:], []byte(endMarker))
-	if end < 0 {
-		return nil, fmt.Errorf("song.link page has unterminated __NEXT_DATA__")
-	}
-
-	return body[start : start+end], nil
+	return buildTrackAvailabilityFromSongLinkLinks(spotifyTrackID, links), nil
 }
 
 func (s *SongLinkClient) checkTrackAvailabilityFromISRC(isrc string) (*TrackAvailability, error) {
@@ -505,47 +518,17 @@ type AlbumAvailability struct {
 }
 
 func (s *SongLinkClient) CheckAlbumAvailability(spotifyAlbumID string) (*AlbumAvailability, error) {
-	songLinkRateLimiter.WaitForSlot()
-
 	spotifyURL := fmt.Sprintf("https://open.spotify.com/album/%s", spotifyAlbumID)
-	apiURL := buildSongLinkURLFromTarget(spotifyURL, "")
-
-	req, err := http.NewRequest("GET", apiURL, nil)
+	links, err := s.resolveTrackPlatforms(spotifyURL)
 	if err != nil {
-		return nil, fmt.Errorf("failed to create request: %w", err)
-	}
-
-	retryConfig := songLinkRetryConfig()
-	resp, err := DoRequestWithRetry(s.client, req, retryConfig)
-	if err != nil {
-		return nil, fmt.Errorf("failed to check album availability: %w", err)
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode != 200 {
-		return nil, fmt.Errorf("API returned status %d", resp.StatusCode)
-	}
-
-	body, err := ReadResponseBody(resp)
-	if err != nil {
-		return nil, fmt.Errorf("failed to read response: %w", err)
-	}
-
-	var songLinkResp struct {
-		LinksByPlatform map[string]struct {
-			URL string `json:"url"`
-		} `json:"linksByPlatform"`
-	}
-
-	if err := json.Unmarshal(body, &songLinkResp); err != nil {
-		return nil, fmt.Errorf("failed to decode response: %w", err)
+		return nil, fmt.Errorf("resolve proxy failed for album %s: %w", spotifyAlbumID, err)
 	}
 
 	availability := &AlbumAvailability{
 		SpotifyID: spotifyAlbumID,
 	}
 
-	if deezerLink, ok := songLinkResp.LinksByPlatform["deezer"]; ok && deezerLink.URL != "" {
+	if deezerLink, ok := links["deezer"]; ok && deezerLink.URL != "" {
 		availability.Deezer = true
 		availability.DeezerURL = deezerLink.URL
 		availability.DeezerID = extractDeezerIDFromURL(deezerLink.URL)
@@ -588,101 +571,19 @@ func (s *SongLinkClient) CheckAvailabilityFromDeezer(deezerTrackID string) (*Tra
 }
 
 func (s *SongLinkClient) checkAvailabilityFromDeezerSongLink(deezerTrackID string) (*TrackAvailability, error) {
-	songLinkRateLimiter.WaitForSlot()
-
 	deezerURL := fmt.Sprintf("https://www.deezer.com/track/%s", deezerTrackID)
-	apiURL := buildSongLinkURLFromTarget(deezerURL, "")
-
-	req, err := http.NewRequest("GET", apiURL, nil)
+	links, err := s.resolveTrackPlatforms(deezerURL)
 	if err != nil {
-		return nil, fmt.Errorf("failed to create request: %w", err)
+		return nil, fmt.Errorf("resolve failed for Deezer %s: %w", deezerTrackID, err)
 	}
 
-	retryConfig := songLinkRetryConfig()
-	resp, err := DoRequestWithRetry(s.client, req, retryConfig)
-	if err != nil {
-		return nil, fmt.Errorf("failed to check availability: %w", err)
+	availability := buildTrackAvailabilityFromSongLinkLinks("", links)
+	// Ensure Deezer is always marked available since we started from a Deezer URL
+	availability.Deezer = true
+	availability.DeezerID = deezerTrackID
+	if availability.DeezerURL == "" {
+		availability.DeezerURL = deezerURL
 	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode == 400 {
-		return nil, fmt.Errorf("track not found on SongLink (invalid Deezer ID)")
-	}
-	if resp.StatusCode == 404 {
-		return nil, fmt.Errorf("track not found on any streaming platform")
-	}
-	if resp.StatusCode == 429 {
-		return nil, fmt.Errorf("SongLink rate limit exceeded")
-	}
-	if resp.StatusCode != 200 {
-		return nil, fmt.Errorf("SongLink API returned status %d", resp.StatusCode)
-	}
-
-	body, err := ReadResponseBody(resp)
-	if err != nil {
-		return nil, fmt.Errorf("failed to read response: %w", err)
-	}
-
-	var songLinkResp struct {
-		LinksByPlatform map[string]struct {
-			URL string `json:"url"`
-		} `json:"linksByPlatform"`
-		EntitiesByUniqueId map[string]struct {
-			ID         string `json:"id"`
-			Type       string `json:"type"`
-			Title      string `json:"title"`
-			ArtistName string `json:"artistName"`
-		} `json:"entitiesByUniqueId"`
-	}
-
-	if err := json.Unmarshal(body, &songLinkResp); err != nil {
-		return nil, fmt.Errorf("failed to decode response: %w", err)
-	}
-
-	availability := &TrackAvailability{
-		Deezer:   true,
-		DeezerID: deezerTrackID,
-	}
-
-	if spotifyLink, ok := songLinkResp.LinksByPlatform["spotify"]; ok && spotifyLink.URL != "" {
-		availability.SpotifyID = extractSpotifyIDFromURL(spotifyLink.URL)
-	}
-
-	if tidalLink, ok := songLinkResp.LinksByPlatform["tidal"]; ok && tidalLink.URL != "" {
-		availability.Tidal = true
-		availability.TidalURL = tidalLink.URL
-		availability.TidalID = extractTidalIDFromURL(tidalLink.URL)
-	}
-
-	if amazonLink, ok := songLinkResp.LinksByPlatform["amazonMusic"]; ok && amazonLink.URL != "" {
-		availability.Amazon = true
-		availability.AmazonURL = amazonLink.URL
-	}
-
-	if qobuzLink, ok := songLinkResp.LinksByPlatform["qobuz"]; ok && qobuzLink.URL != "" {
-		availability.Qobuz = true
-		availability.QobuzURL = qobuzLink.URL
-		availability.QobuzID = extractQobuzIDFromURL(qobuzLink.URL)
-	}
-
-	if deezerLink, ok := songLinkResp.LinksByPlatform["deezer"]; ok && deezerLink.URL != "" {
-		availability.DeezerURL = deezerLink.URL
-	}
-
-	// Prefer youtubeMusic URLs — they are usually closer to music catalog matches.
-	if ytMusicLink, ok := songLinkResp.LinksByPlatform["youtubeMusic"]; ok && ytMusicLink.URL != "" {
-		availability.YouTube = true
-		availability.YouTubeURL = ytMusicLink.URL
-		availability.YouTubeID = extractYouTubeIDFromURL(ytMusicLink.URL)
-	}
-	if !availability.YouTube {
-		if youtubeLink, ok := songLinkResp.LinksByPlatform["youtube"]; ok && youtubeLink.URL != "" {
-			availability.YouTube = true
-			availability.YouTubeURL = youtubeLink.URL
-			availability.YouTubeID = extractYouTubeIDFromURL(youtubeLink.URL)
-		}
-	}
-
 	return availability, nil
 }
 
@@ -694,94 +595,12 @@ func (s *SongLinkClient) CheckAvailabilityByPlatform(platform, entityType, entit
 		return nil, fmt.Errorf("%s ID is empty", platform)
 	}
 
-	songLinkRateLimiter.WaitForSlot()
-
-	apiURL := buildSongLinkURLByPlatform(platform, entityType, entityID, "")
-
-	req, err := http.NewRequest("GET", apiURL, nil)
+	links, err := s.resolveTrackPlatformsByPlatform(platform, entityType, entityID)
 	if err != nil {
-		return nil, fmt.Errorf("failed to create request: %w", err)
+		return nil, fmt.Errorf("resolve failed for %s %s: %w", platform, entityID, err)
 	}
 
-	retryConfig := songLinkRetryConfig()
-	resp, err := DoRequestWithRetry(s.client, req, retryConfig)
-	if err != nil {
-		return nil, fmt.Errorf("failed to check availability: %w", err)
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode == 400 {
-		return nil, fmt.Errorf("track not found on SongLink (invalid %s ID)", platform)
-	}
-	if resp.StatusCode == 404 {
-		return nil, fmt.Errorf("track not found on any streaming platform")
-	}
-	if resp.StatusCode == 429 {
-		return nil, fmt.Errorf("SongLink rate limit exceeded")
-	}
-	if resp.StatusCode != 200 {
-		return nil, fmt.Errorf("SongLink API returned status %d", resp.StatusCode)
-	}
-
-	body, err := ReadResponseBody(resp)
-	if err != nil {
-		return nil, fmt.Errorf("failed to read response: %w", err)
-	}
-
-	var songLinkResp struct {
-		LinksByPlatform map[string]struct {
-			URL string `json:"url"`
-		} `json:"linksByPlatform"`
-	}
-
-	if err := json.Unmarshal(body, &songLinkResp); err != nil {
-		return nil, fmt.Errorf("failed to decode response: %w", err)
-	}
-
-	availability := &TrackAvailability{}
-
-	if spotifyLink, ok := songLinkResp.LinksByPlatform["spotify"]; ok && spotifyLink.URL != "" {
-		availability.SpotifyID = extractSpotifyIDFromURL(spotifyLink.URL)
-	}
-
-	if tidalLink, ok := songLinkResp.LinksByPlatform["tidal"]; ok && tidalLink.URL != "" {
-		availability.Tidal = true
-		availability.TidalURL = tidalLink.URL
-		availability.TidalID = extractTidalIDFromURL(tidalLink.URL)
-	}
-
-	if amazonLink, ok := songLinkResp.LinksByPlatform["amazonMusic"]; ok && amazonLink.URL != "" {
-		availability.Amazon = true
-		availability.AmazonURL = amazonLink.URL
-	}
-
-	if qobuzLink, ok := songLinkResp.LinksByPlatform["qobuz"]; ok && qobuzLink.URL != "" {
-		availability.Qobuz = true
-		availability.QobuzURL = qobuzLink.URL
-		availability.QobuzID = extractQobuzIDFromURL(qobuzLink.URL)
-	}
-
-	if deezerLink, ok := songLinkResp.LinksByPlatform["deezer"]; ok && deezerLink.URL != "" {
-		availability.Deezer = true
-		availability.DeezerURL = deezerLink.URL
-		availability.DeezerID = extractDeezerIDFromURL(deezerLink.URL)
-	}
-
-	// Prefer youtubeMusic URLs — they are usually closer to music catalog matches.
-	if ytMusicLink, ok := songLinkResp.LinksByPlatform["youtubeMusic"]; ok && ytMusicLink.URL != "" {
-		availability.YouTube = true
-		availability.YouTubeURL = ytMusicLink.URL
-		availability.YouTubeID = extractYouTubeIDFromURL(ytMusicLink.URL)
-	}
-	if !availability.YouTube {
-		if youtubeLink, ok := songLinkResp.LinksByPlatform["youtube"]; ok && youtubeLink.URL != "" {
-			availability.YouTube = true
-			availability.YouTubeURL = youtubeLink.URL
-			availability.YouTubeID = extractYouTubeIDFromURL(youtubeLink.URL)
-		}
-	}
-
-	return availability, nil
+	return buildTrackAvailabilityFromSongLinkLinks("", links), nil
 }
 
 func buildTrackAvailabilityFromSongLinkLinks(spotifyTrackID string, links map[string]songLinkPlatformLink) *TrackAvailability {
@@ -894,85 +713,10 @@ func (s *SongLinkClient) GetYouTubeURLFromDeezer(deezerTrackID string) (string,
 }
 
 func (s *SongLinkClient) CheckAvailabilityFromURL(inputURL string) (*TrackAvailability, error) {
-	songLinkRateLimiter.WaitForSlot()
-
-	apiURL := buildSongLinkURLFromTarget(inputURL, "")
-
-	req, err := http.NewRequest("GET", apiURL, nil)
+	links, err := s.resolveTrackPlatforms(inputURL)
 	if err != nil {
-		return nil, fmt.Errorf("failed to create request: %w", err)
+		return nil, fmt.Errorf("resolve failed for URL %s: %w", inputURL, err)
 	}
 
-	retryConfig := songLinkRetryConfig()
-	resp, err := DoRequestWithRetry(s.client, req, retryConfig)
-	if err != nil {
-		return nil, fmt.Errorf("failed to check availability: %w", err)
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode == 400 || resp.StatusCode == 404 {
-		return nil, fmt.Errorf("track not found on SongLink")
-	}
-	if resp.StatusCode == 429 {
-		return nil, fmt.Errorf("SongLink rate limit exceeded")
-	}
-	if resp.StatusCode != 200 {
-		return nil, fmt.Errorf("SongLink API returned status %d", resp.StatusCode)
-	}
-
-	body, err := ReadResponseBody(resp)
-	if err != nil {
-		return nil, fmt.Errorf("failed to read response: %w", err)
-	}
-
-	var songLinkResp struct {
-		LinksByPlatform map[string]struct {
-			URL      string `json:"url"`
-			EntityID string `json:"entityUniqueId"`
-		} `json:"linksByPlatform"`
-	}
-
-	if err := json.Unmarshal(body, &songLinkResp); err != nil {
-		return nil, fmt.Errorf("failed to decode response: %w", err)
-	}
-
-	availability := &TrackAvailability{}
-
-	if spotifyLink, ok := songLinkResp.LinksByPlatform["spotify"]; ok && spotifyLink.URL != "" {
-		availability.SpotifyID = extractSpotifyIDFromURL(spotifyLink.URL)
-	}
-	if tidalLink, ok := songLinkResp.LinksByPlatform["tidal"]; ok && tidalLink.URL != "" {
-		availability.Tidal = true
-		availability.TidalURL = tidalLink.URL
-		availability.TidalID = extractTidalIDFromURL(tidalLink.URL)
-	}
-	if amazonLink, ok := songLinkResp.LinksByPlatform["amazonMusic"]; ok && amazonLink.URL != "" {
-		availability.Amazon = true
-		availability.AmazonURL = amazonLink.URL
-	}
-	if qobuzLink, ok := songLinkResp.LinksByPlatform["qobuz"]; ok && qobuzLink.URL != "" {
-		availability.Qobuz = true
-		availability.QobuzURL = qobuzLink.URL
-		availability.QobuzID = extractQobuzIDFromURL(qobuzLink.URL)
-	}
-	if deezerLink, ok := songLinkResp.LinksByPlatform["deezer"]; ok && deezerLink.URL != "" {
-		availability.Deezer = true
-		availability.DeezerURL = deezerLink.URL
-		availability.DeezerID = extractDeezerIDFromURL(deezerLink.URL)
-	}
-	// Prefer youtubeMusic URLs — they are usually closer to music catalog matches.
-	if ytMusicLink, ok := songLinkResp.LinksByPlatform["youtubeMusic"]; ok && ytMusicLink.URL != "" {
-		availability.YouTube = true
-		availability.YouTubeURL = ytMusicLink.URL
-		availability.YouTubeID = extractYouTubeIDFromURL(ytMusicLink.URL)
-	}
-	if !availability.YouTube {
-		if youtubeLink, ok := songLinkResp.LinksByPlatform["youtube"]; ok && youtubeLink.URL != "" {
-			availability.YouTube = true
-			availability.YouTubeURL = youtubeLink.URL
-			availability.YouTubeID = extractYouTubeIDFromURL(youtubeLink.URL)
-		}
-	}
-
-	return availability, nil
+	return buildTrackAvailabilityFromSongLinkLinks("", links), nil
 }

go_backend/songlink_test.go

@@ -23,26 +23,24 @@ func TestGetRetryAfterDurationMissingHeaderReturnsZero(t *testing.T) {
 	}
 }
 
-func TestCheckTrackAvailabilityFromSpotifyPrefersSongLinkPage(t *testing.T) {
+func TestCheckTrackAvailabilityFromSpotifyViaResolveAPI(t *testing.T) {
+	origRetryConfig := songLinkRetryConfig
+	defer func() { songLinkRetryConfig = origRetryConfig }()
+
 	client := &SongLinkClient{
 		client: &http.Client{
 			Transport: roundTripFunc(func(req *http.Request) (*http.Response, error) {
-				switch {
-				case req.URL.Host == "api.song.link":
-					t.Fatalf("api.song.link should not be called when song.link page succeeds")
-					return nil, nil
-				case req.URL.Host == "song.link" && req.URL.Path == "/s/testspotifyid":
-					body := `<!DOCTYPE html><html><body><script id="__NEXT_DATA__" type="application/json">{"props":{"pageProps":{"pageData":{"sections":[{"displayName":"Listen","links":[{"platform":"spotify","url":"https://open.spotify.com/track/testspotifyid","show":true},{"platform":"deezer","url":"https://www.deezer.com/track/908604612","show":true},{"platform":"amazonMusic","url":"https://music.amazon.com/albums/B086Q2QNLH?trackAsin=B086Q41M9C","show":true},{"platform":"tidal","url":"https://listen.tidal.com/track/134858527","show":true},{"platform":"qobuz","url":"https://open.qobuz.com/track/195125822","show":true},{"platform":"youtubeMusic","url":"https://music.youtube.com/watch?v=testvideoid1","show":true}]}]}}}}</script></body></html>`
+				if req.URL.Host == "api.zarz.moe" && req.URL.Path == "/v1/resolve" && req.Method == "POST" {
+					body := `{"success":true,"isrc":"USRC12345678","songUrls":{"Spotify":"https://open.spotify.com/track/testspotifyid","Deezer":"https://www.deezer.com/track/908604612","AmazonMusic":"https://music.amazon.com/albums/B086Q2QNLH?trackAsin=B086Q41M9C","Tidal":"https://listen.tidal.com/track/134858527","Qobuz":"https://open.qobuz.com/track/195125822","YouTubeMusic":"https://music.youtube.com/watch?v=testvideoid1"}}`
 					return &http.Response{
 						StatusCode: 200,
 						Header:     make(http.Header),
 						Body:       io.NopCloser(strings.NewReader(body)),
 						Request:    req,
 					}, nil
-				default:
-					t.Fatalf("unexpected request: %s", req.URL.String())
-					return nil, nil
 				}
+				t.Fatalf("unexpected request: %s %s", req.Method, req.URL.String())
+				return nil, nil
 			}),
 		},
 	}
@@ -66,62 +64,95 @@ func TestCheckTrackAvailabilityFromSpotifyPrefersSongLinkPage(t *testing.T) {
 	}
 }
 
-func TestCheckTrackAvailabilityFromSpotifyFallsBackToAPIWhenPageFails(t *testing.T) {
+func TestCheckTrackAvailabilityFromSpotifyResolveAPIFailure(t *testing.T) {
 	origRetryConfig := songLinkRetryConfig
 	songLinkRetryConfig = func() RetryConfig {
-		return RetryConfig{
-			MaxRetries:    0,
-			InitialDelay:  0,
-			MaxDelay:      0,
-			BackoffFactor: 1,
-		}
+		return RetryConfig{MaxRetries: 0, InitialDelay: 0, MaxDelay: 0, BackoffFactor: 1}
 	}
-	defer func() {
-		songLinkRetryConfig = origRetryConfig
-	}()
+	defer func() { songLinkRetryConfig = origRetryConfig }()
+
+	var hitSongLink bool
 
 	client := &SongLinkClient{
 		client: &http.Client{
 			Transport: roundTripFunc(func(req *http.Request) (*http.Response, error) {
-				switch {
-				case req.URL.Host == "song.link" && req.URL.Path == "/s/testspotifyid":
+				// Resolve proxy returns 500
+				if req.URL.Host == "api.zarz.moe" && req.URL.Path == "/v1/resolve" {
 					return &http.Response{
 						StatusCode: 500,
 						Header:     make(http.Header),
-						Body:       io.NopCloser(strings.NewReader("page failure")),
+						Body:       io.NopCloser(strings.NewReader("internal error")),
 						Request:    req,
 					}, nil
-				case req.URL.Host == "api.song.link":
-					body := `{"linksByPlatform":{"spotify":{"url":"https://open.spotify.com/track/testspotifyid"},"deezer":{"url":"https://www.deezer.com/track/908604612"},"amazonMusic":{"url":"https://music.amazon.com/albums/B086Q2QNLH?trackAsin=B086Q41M9C"},"tidal":{"url":"https://listen.tidal.com/track/134858527"},"qobuz":{"url":"https://open.qobuz.com/track/195125822"},"youtubeMusic":{"url":"https://music.youtube.com/watch?v=testvideoid1"}}}`
+				}
+				// SongLink fallback should be called
+				if req.URL.Host == "api.song.link" {
+					hitSongLink = true
+					body := `{"linksByPlatform":{"spotify":{"url":"https://open.spotify.com/track/testspotifyid"},"deezer":{"url":"https://www.deezer.com/track/908604612"},"tidal":{"url":"https://listen.tidal.com/track/134858527"}}}`
 					return &http.Response{
 						StatusCode: 200,
 						Header:     make(http.Header),
 						Body:       io.NopCloser(strings.NewReader(body)),
 						Request:    req,
 					}, nil
-				default:
-					t.Fatalf("unexpected request: %s", req.URL.String())
-					return nil, nil
 				}
+				t.Fatalf("unexpected request: %s %s", req.Method, req.URL.String())
+				return nil, nil
 			}),
 		},
 	}
 
 	availability, err := client.CheckTrackAvailability("testspotifyid", "")
 	if err != nil {
-		t.Fatalf("CheckTrackAvailability() error = %v", err)
+		t.Fatalf("expected SongLink fallback to succeed, got error: %v", err)
 	}
-
-	if availability.SpotifyID != "testspotifyid" {
-		t.Fatalf("SpotifyID = %q, want %q", availability.SpotifyID, "testspotifyid")
+	if !hitSongLink {
+		t.Fatal("expected fallback request to SongLink API, but it was never called")
 	}
 	if !availability.Deezer || availability.DeezerID != "908604612" {
-		t.Fatalf("Deezer availability = %+v, want DeezerID 908604612", availability)
-	}
-	if !availability.Amazon || !availability.Tidal || !availability.Qobuz || !availability.YouTube {
-		t.Fatalf("availability flags = %+v, want Amazon/Tidal/Qobuz/YouTube true", availability)
-	}
-	if availability.YouTubeID != "testvideoid1" {
-		t.Fatalf("YouTubeID = %q, want %q", availability.YouTubeID, "testvideoid1")
+		t.Fatalf("Deezer availability via fallback = %+v, want DeezerID 908604612", availability)
+	}
+}
+
+func TestCheckAvailabilityFromDeezerUsesSongLink(t *testing.T) {
+	origRetryConfig := songLinkRetryConfig
+	songLinkRetryConfig = func() RetryConfig {
+		return RetryConfig{MaxRetries: 0, InitialDelay: 0, MaxDelay: 0, BackoffFactor: 1}
+	}
+	defer func() { songLinkRetryConfig = origRetryConfig }()
+
+	client := &SongLinkClient{
+		client: &http.Client{
+			Transport: roundTripFunc(func(req *http.Request) (*http.Response, error) {
+				// Non-Spotify should go to SongLink, not resolve API
+				if req.URL.Host == "api.zarz.moe" {
+					t.Fatalf("non-Spotify URL should not hit resolve API, got: %s", req.URL.String())
+					return nil, nil
+				}
+				if req.URL.Host == "api.song.link" {
+					body := `{"linksByPlatform":{"spotify":{"url":"https://open.spotify.com/track/testid"},"deezer":{"url":"https://www.deezer.com/track/908604612"},"tidal":{"url":"https://listen.tidal.com/track/134858527"},"qobuz":{"url":"https://open.qobuz.com/track/195125822"},"youtubeMusic":{"url":"https://music.youtube.com/watch?v=testvid"}}}`
+					return &http.Response{
+						StatusCode: 200,
+						Header:     make(http.Header),
+						Body:       io.NopCloser(strings.NewReader(body)),
+						Request:    req,
+					}, nil
+				}
+				t.Fatalf("unexpected request: %s %s", req.Method, req.URL.String())
+				return nil, nil
+			}),
+		},
+	}
+
+	availability, err := client.checkAvailabilityFromDeezerSongLink("908604612")
+	if err != nil {
+		t.Fatalf("checkAvailabilityFromDeezerSongLink() error = %v", err)
+	}
+
+	if !availability.Deezer || availability.DeezerID != "908604612" {
+		t.Fatalf("Deezer = %+v, want DeezerID 908604612", availability)
+	}
+	if availability.SpotifyID != "testid" {
+		t.Fatalf("SpotifyID = %q, want %q", availability.SpotifyID, "testid")
 	}
 }

go_backend/tidal.go

@@ -875,8 +875,6 @@ func (t *TidalDownloader) SearchTracks(query string, limit int) ([]ExtTrackMetad
 	return results, nil
 }
 
-// SearchAll searches Tidal for tracks, artists, and albums matching the query.
-// Returns results in the same SearchAllResult format as Deezer's SearchAll.
 func (t *TidalDownloader) SearchAll(query string, trackLimit, artistLimit int, filter string) (*SearchAllResult, error) {
 	GoLog("[Tidal] SearchAll: query=%q, trackLimit=%d, artistLimit=%d, filter=%q\n", query, trackLimit, artistLimit, filter)
 
@@ -1165,7 +1163,6 @@ type tidalAPIResult struct {
 	duration time.Duration
 }
 
-// Mobile networks are more unstable, so we use longer timeouts
 const (
 	tidalAPITimeoutMobile = 25 * time.Second
 	tidalMaxRetries       = 2
@@ -1211,7 +1208,6 @@ func fetchTidalURLWithRetry(api string, trackID int64, quality string, timeout t
 			continue
 		}
 
-		// 429 rate limit - wait and retry
 		if resp.StatusCode == 429 {
 			io.Copy(io.Discard, resp.Body)
 			resp.Body.Close()
@@ -1233,7 +1229,6 @@ func fetchTidalURLWithRetry(api string, trackID int64, quality string, timeout t
 			continue
 		}
 
-		// Try V2 response format (with manifest)
 		var v2Response TidalAPIResponseV2
 		if err := json.Unmarshal(body, &v2Response); err == nil && v2Response.Data.Manifest != "" {
 			if v2Response.Data.AssetPresentation == "PREVIEW" {
@@ -1247,7 +1242,6 @@ func fetchTidalURLWithRetry(api string, trackID int64, quality string, timeout t
 			}, nil
 		}
 
-		// Try V1 response format
 		var v1Responses []struct {
 			OriginalTrackURL string `json:"OriginalTrackUrl"`
 		}
@@ -1602,10 +1596,6 @@ func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64,
 		return nil
 	}
 
-	// For DASH format, determine correct M4A path
-	// If outputPath already ends with .m4a, use it directly.
-	// If outputPath ends with .flac, convert .flac to .m4a.
-	// Otherwise (e.g., SAF /proc/self/fd/*), use outputPath as-is.
 	var m4aPath string
 	if strings.HasSuffix(outputPath, ".m4a") {
 		m4aPath = outputPath
@@ -1879,8 +1869,6 @@ func titlesMatch(expectedTitle, foundTitle string) bool {
 		}
 	}
 
-	// Emoji/symbol-only titles must be matched strictly to avoid false positives
-	// like mapping "🪐" to "Higher Power".
 	if (!hasAlphaNumericRunes(expectedTitle) || !hasAlphaNumericRunes(foundTitle)) &&
 		strings.TrimSpace(expectedTitle) != "" &&
 		strings.TrimSpace(foundTitle) != "" {
@@ -2111,7 +2099,6 @@ func resolveTidalTrackForRequest(req DownloadRequest, downloader *TidalDownloade
 			}
 		}
 
-		// Prefer Deezer-based SongLink lookup when DeezerID is available.
 		if req.DeezerID != "" {
 			GoLog("[%s] Using Deezer ID for SongLink lookup: %s\n", logPrefix, req.DeezerID)
 			songlink := NewSongLinkClient()
@@ -2150,11 +2137,9 @@ func resolveTidalTrackForRequest(req DownloadRequest, downloader *TidalDownloade
 		return nil, fmt.Errorf("failed to find tidal track id from request/cache/songlink")
 	}
 
-	// Verify the resolved track matches the request.
 	actualTrack, fetchErr := tidalGetPublicTrackFunc(downloader, strconv.FormatInt(trackID, 10))
 	if fetchErr != nil {
 		GoLog("[%s] Warning: could not fetch Tidal track %d for verification: %v\n", logPrefix, trackID, fetchErr)
-		// Continue without verification — better than failing entirely.
 	} else {
 		providerArtist := actualTrack.Artist.Name
 		if providerArtist == "" && len(actualTrack.Artists) > 0 {
@@ -2168,7 +2153,6 @@ func resolveTidalTrackForRequest(req DownloadRequest, downloader *TidalDownloade
 			SkipNameVerification: resolvedViaSongLink,
 		}
 		if !trackMatchesRequest(req, resolved, logPrefix) {
-			// Invalidate the cached ID so future requests don't reuse it.
 			if req.ISRC != "" {
 				GetTrackIDCache().SetTidal(req.ISRC, 0)
 			}
@@ -2497,7 +2481,6 @@ func parseTidalURL(input string) (string, string, error) {
 
 	parts := strings.Split(strings.Trim(parsed.Path, "/"), "/")
 
-	// Handle /browse/track/123 format
 	if len(parts) > 0 && parts[0] == "browse" {
 		parts = parts[1:]
 	}

go_backend/title_match_utils.go

@@ -22,8 +22,6 @@ func writeNormalizedArtistRune(b *strings.Builder, r rune) {
 	}
 }
 
-// normalizeLooseTitle collapses separators/punctuation so titles like
-// "Doctor / Cops" and "Doctor _ Cops" can still match.
 func normalizeLooseTitle(title string) string {
 	trimmed := strings.TrimSpace(strings.ToLower(title))
 	if trimmed == "" {
@@ -48,8 +46,6 @@ func normalizeLooseTitle(title string) string {
 	return strings.Join(strings.Fields(b.String()), " ")
 }
 
-// normalizeLooseArtistName folds diacritics and common separators so artist
-// verification is resilient to variants like "Özkent" vs "Ozkent".
 func normalizeLooseArtistName(name string) string {
 	trimmed := strings.TrimSpace(strings.ToLower(name))
 	if trimmed == "" {
@@ -87,9 +83,6 @@ func hasAlphaNumericRunes(value string) bool {
 	return false
 }
 
-// normalizeSymbolOnlyTitle keeps symbol/emoji runes while dropping letters,
-// digits, spaces and punctuation. This is useful for emoji-only titles such as
-// "🪐", "🌎" etc, so we can compare them strictly and avoid false matches.
 func normalizeSymbolOnlyTitle(title string) string {
 	trimmed := strings.TrimSpace(strings.ToLower(title))
 	if trimmed == "" {
@@ -114,7 +107,6 @@ func normalizeSymbolOnlyTitle(title string) string {
 	return b.String()
 }
 
-// resolvedTrackInfo holds the metadata fetched from a provider for verification.
 type resolvedTrackInfo struct {
 	Title                string
 	ArtistName           string
@@ -123,8 +115,6 @@ type resolvedTrackInfo struct {
 	SkipNameVerification bool
 }
 
-// trackMatchesRequest checks whether a resolved track from a provider matches
-// the original download request. Returns true if the track is a plausible match.
 func trackMatchesRequest(req DownloadRequest, resolved resolvedTrackInfo, logPrefix string) bool {
 	exactISRCMatch := req.ISRC != "" &&
 		resolved.ISRC != "" &&

ios/Runner/AppDelegate.swift

@@ -296,6 +296,15 @@ import Gobackend  // Import Go framework
             if let error = error { throw error }
             return response
             
+        case "rewriteSplitArtistTags":
+            let args = call.arguments as! [String: Any]
+            let filePath = args["file_path"] as! String
+            let artist = args["artist"] as! String
+            let albumArtist = args["album_artist"] as! String
+            let response = GobackendRewriteSplitArtistTagsExport(filePath, artist, albumArtist, &error)
+            if let error = error { throw error }
+            return response
+            
         case "cleanupConnections":
             GobackendCleanupConnections()
             return nil

lib/main.dart

@@ -82,7 +82,6 @@ class _RuntimeProfile {
   });
 }
 
-/// Widget to eagerly initialize providers that need to load data on startup
 class _EagerInitialization extends ConsumerStatefulWidget {
   const _EagerInitialization({required this.child});
   final Widget child;
@@ -170,10 +169,8 @@ class _EagerInitializationState extends ConsumerState<_EagerInitialization>
       const Duration(milliseconds: 1600),
       () {
         ref.read(localLibraryProvider);
-        // Trigger auto-scan after initial warmup on first app launch.
         if (!_autoScanTriggeredOnLaunch) {
           _autoScanTriggeredOnLaunch = true;
-          // Give the provider a moment to load existing data before scanning.
           Future.delayed(const Duration(milliseconds: 500), () {
             if (mounted) _maybeAutoScanLocalLibrary();
           });
@@ -182,8 +179,6 @@ class _EagerInitializationState extends ConsumerState<_EagerInitialization>
     );
   }
 
-  /// Checks whether an automatic incremental scan should be triggered based on
-  /// the user's auto-scan preference and the time since the last scan.
   Future<void> _maybeAutoScanLocalLibrary() async {
     if (!mounted) return;
 
@@ -204,7 +199,6 @@ class _EagerInitializationState extends ConsumerState<_EagerInitialization>
 
       switch (settings.localLibraryAutoScan) {
         case 'on_open':
-          // Cooldown of 10 minutes to prevent rapid re-scans.
           if (elapsed.inMinutes < 10) return;
           break;
         case 'daily':

lib/providers/download_queue_provider.dart

@@ -20,6 +20,7 @@ import 'package:spotiflac_android/services/history_database.dart';
 import 'package:spotiflac_android/utils/logger.dart';
 import 'package:spotiflac_android/utils/file_access.dart';
 import 'package:spotiflac_android/utils/string_utils.dart';
+import 'package:spotiflac_android/utils/artist_utils.dart';
 
 final _log = AppLogger('DownloadQueue');
 final _historyLog = AppLogger('DownloadHistory');
@@ -3010,6 +3011,22 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
         _log.w('FFmpeg metadata/cover embed failed');
       }
 
+      // After FFmpeg embed, fix split artist tags using native FLAC writer.
+      // FFmpeg deduplicates repeated metadata keys, so multiple ARTIST entries
+      // collapse into one. The Go FLAC writer rewrites them properly.
+      if (settings.artistTagMode == artistTagModeSplitVorbis) {
+        try {
+          await PlatformBridge.rewriteSplitArtistTags(
+            flacPath,
+            track.artistName,
+            albumArtist,
+          );
+          _log.d('Split artist tags rewritten via native FLAC writer');
+        } catch (e) {
+          _log.w('Failed to rewrite split artist tags: $e');
+        }
+      }
+
       if (coverPath != null) {
         try {
           final coverFile = File(coverPath);

lib/providers/store_provider.dart

@@ -146,7 +146,6 @@ class StoreState {
     this.registryUrl = '',
   });
 
-  /// Whether a registry URL has been configured by the user.
   bool get hasRegistryUrl => registryUrl.isNotEmpty;
 
   StoreState copyWith({
@@ -218,7 +217,6 @@ class StoreNotifier extends Notifier<StoreState> {
   Future<void> initialize(String cacheDir) async {
     if (state.isInitialized) return;
 
-    // Load saved registry URL early to avoid UI flash (empty → setup screen)
     final prefs = await SharedPreferences.getInstance();
     final savedUrl = prefs.getString(_registryUrlPrefKey) ?? '';
 
@@ -246,8 +244,6 @@ class StoreNotifier extends Notifier<StoreState> {
     }
   }
 
-  /// Sets the registry URL, saves it, and refreshes the store.
-  /// The Go backend handles URL normalisation (GitHub repo → raw URL, branch detection).
   Future<void> setRegistryUrl(String url) async {
     final trimmed = url.trim();
     if (trimmed.isEmpty) {
@@ -258,10 +254,8 @@ class StoreNotifier extends Notifier<StoreState> {
     state = state.copyWith(isLoading: true, clearError: true);
 
     try {
-      // Go backend resolves GitHub URLs (detects default branch) and validates HTTPS.
       await PlatformBridge.setStoreRegistryUrl(trimmed);
 
-      // Read back the resolved URL (may differ from input after normalisation).
       final resolvedUrl = await PlatformBridge.getStoreRegistryUrl();
 
       final prefs = await SharedPreferences.getInstance();
@@ -280,13 +274,11 @@ class StoreNotifier extends Notifier<StoreState> {
     }
   }
 
-  /// Removes the saved registry URL and fully detaches the repo from backend.
   Future<void> removeRegistryUrl() async {
     try {
       final prefs = await SharedPreferences.getInstance();
       await prefs.remove(_registryUrlPrefKey);
 
-      // Reset the URL in Go backend memory AND clear its cache
       await PlatformBridge.clearStoreRegistryUrl();
 
       state = state.copyWith(

lib/screens/album_screen.dart

@@ -138,14 +138,11 @@ class _AlbumScreenState extends ConsumerState<AlbumScreen> {
     return (mediaSize.height * 0.55).clamp(360.0, 520.0);
   }
 
-  /// Upgrade cover URL to a higher resolution for full-screen display.
   String? _highResCoverUrl(String? url) {
     if (url == null) return null;
-    // Spotify CDN: upgrade 300 → 640 only (no intermediate between 640 and 2000)
     if (url.contains('ab67616d00001e02')) {
       return url.replaceAll('ab67616d00001e02', 'ab67616d0000b273');
     }
-    // Deezer CDN: upgrade to 1000x1000
     final deezerRegex = RegExp(r'/(\d+)x(\d+)-(\d+)-(\d+)-(\d+)-(\d+)\.jpg$');
     if (url.contains('cdn-images.dzcdn.net') && deezerRegex.hasMatch(url)) {
       return url.replaceAllMapped(

lib/screens/artist_screen.dart

@@ -228,7 +228,6 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
   }
 
   void _onScroll() {
-    // Show title when scrolled past the header (280px trigger)
     final shouldShow = _scrollController.offset > 280;
     if (shouldShow != _showTitleInAppBar) {
       setState(() => _showTitleInAppBar = shouldShow);
@@ -2013,7 +2012,6 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
   }
 }
 
-/// Option tile for discography download bottom sheet
 class _DiscographyOptionTile extends StatelessWidget {
   final IconData icon;
   final String title;
@@ -2051,7 +2049,6 @@ class _DiscographyOptionTile extends StatelessWidget {
   }
 }
 
-/// Progress dialog shown while fetching album tracks
 class _FetchingProgressDialog extends StatefulWidget {
   final int totalAlbums;
   final VoidCallback onCancel;

lib/screens/downloaded_album_screen.dart

@@ -95,7 +95,6 @@ class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
     return (mediaSize.height * 0.55).clamp(360.0, 520.0);
   }
 
-  /// Upgrade cover URL to a reasonable resolution for full-screen display.
   String? _highResCoverUrl(String? url) {
     if (url == null) return null;
     if (url.contains('ab67616d00001e02')) {
@@ -111,7 +110,6 @@ class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
     return url;
   }
 
-  /// Get tracks for this album from history provider (reactive)
   List<DownloadHistoryItem> _getAlbumTracks(
     List<DownloadHistoryItem> allItems,
   ) {
@@ -641,7 +639,6 @@ class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
     ColorScheme colorScheme,
     List<DownloadHistoryItem> tracks,
   ) {
-    // Info is now displayed in the full-screen cover overlay
     return const SliverToBoxAdapter(child: SizedBox.shrink());
   }
 
@@ -848,7 +845,6 @@ class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
     );
   }
 
-  /// Share selected tracks via system share sheet
   Future<void> _shareSelected(List<DownloadHistoryItem> allTracks) async {
     final tracksById = {for (final t in allTracks) t.id: t};
     final safUris = <String>[];
@@ -1091,7 +1087,6 @@ class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
     for (final id in _selectedIds) {
       final item = tracksById[id];
       if (item == null) continue;
-      // For SAF items, use safFileName to detect format (filePath is content:// URI)
       final nameToCheck =
           (item.safFileName != null && item.safFileName!.isNotEmpty)
           ? item.safFileName!.toLowerCase()

lib/screens/home_tab.dart

@@ -2412,8 +2412,6 @@ class _HomeTabState extends ConsumerState<HomeTab>
     );
   }
 
-  // ── Search result sorting ──────────────────────────────────────────────
-
   String _sortOptionLabel(_SearchSortOption option) {
     switch (option) {
       case _SearchSortOption.defaultOrder:

lib/screens/library_tracks_folder_screen.dart

@@ -597,7 +597,6 @@ class _LibraryTracksFolderScreenState
     final customCoverPath = playlist?.coverImagePath;
     final isLovedMode = widget.mode == LibraryTracksFolderMode.loved;
     final isPlaylistMode = widget.mode == LibraryTracksFolderMode.playlist;
-    // Loved always shows the heart icon (like Spotify's Liked Songs)
     final coverUrl = isLovedMode ? null : _firstCoverUrl(entries, localState);
     final hasCustomCover =
         customCoverPath != null && customCoverPath.isNotEmpty;
@@ -667,7 +666,6 @@ class _LibraryTracksFolderScreenState
             background: Stack(
               fit: StackFit.expand,
               children: [
-                // Cover background: custom > first track URL > icon
                 if (hasCustomCover)
                   Image.file(
                     File(customCoverPath),
@@ -1364,15 +1362,12 @@ class _CollectionTrackTile extends ConsumerWidget {
     final track = entry.track;
     final historyState = ref.read(downloadHistoryProvider);
 
-    // 1. Download history by Spotify ID
     var historyItem = historyState.getBySpotifyId(track.id);
 
-    // 2. Download history by ISRC
     if (historyItem == null && track.isrc != null && track.isrc!.isNotEmpty) {
       historyItem = historyState.getByIsrc(track.isrc!);
     }
 
-    // 3. Download history by track name + artist (handles ID/ISRC mismatch)
     historyItem ??= historyState.findByTrackAndArtist(
       track.name,
       track.artistName,
@@ -1385,14 +1380,12 @@ class _CollectionTrackTile extends ConsumerWidget {
       return;
     }
 
-    // 4. Local library by ISRC
     final localState = ref.read(localLibraryProvider);
     LocalLibraryItem? localItem;
     if (track.isrc != null && track.isrc!.isNotEmpty) {
       localItem = localState.getByIsrc(track.isrc!);
     }
 
-    // 5. Local library by track name + artist
     localItem ??= localState.findByTrackAndArtist(track.name, track.artistName);
 
     if (localItem != null) {
@@ -1402,7 +1395,6 @@ class _CollectionTrackTile extends ConsumerWidget {
       return;
     }
 
-    // 6. Not found anywhere — offer to download
     _downloadTrack(context, ref);
   }
 }

lib/screens/local_album_screen.dart

@@ -526,7 +526,6 @@ class _LocalAlbumScreenState extends ConsumerState<LocalAlbumScreen> {
     ColorScheme colorScheme,
     List<LocalLibraryItem> tracks,
   ) {
-    // Info is now displayed in the full-screen cover overlay
     return const SliverToBoxAdapter(child: SizedBox.shrink());
   }
 
@@ -1057,7 +1056,6 @@ class _LocalAlbumScreenState extends ConsumerState<LocalAlbumScreen> {
       return;
     }
 
-    // Temporarily hide selection bar so it doesn't overlap the bottom sheet.
     // The bar uses AnimatedPositioned (250ms), so wait for the slide-out.
     setState(() => _isSelectionMode = false);
     await Future<void>.delayed(const Duration(milliseconds: 300));

lib/screens/main_shell.dart

@@ -348,7 +348,6 @@ class _MainShellState extends ConsumerState<MainShell>
         trackState.isShowingRecentAccess &&
         !trackState.isLoading &&
         (trackState.hasSearchText || trackState.hasContent)) {
-      // Has recent access AND search content — clear everything at once
       _log.i(
         'Back: step 3a - dismiss recent access + clear search/content '
         '(hasSearchText=${trackState.hasSearchText}, hasContent=${trackState.hasContent})',
@@ -360,7 +359,6 @@ class _MainShellState extends ConsumerState<MainShell>
     }
 
     if (_currentIndex == 0 && trackState.isShowingRecentAccess) {
-      // Recent access overlay only (no search content) — just dismiss it
       _log.i('Back: step 3b - dismiss recent access only');
       ref.read(trackProvider.notifier).setShowingRecentAccess(false);
       FocusManager.instance.primaryFocus?.unfocus();

lib/screens/playlist_screen.dart

@@ -117,7 +117,6 @@ class _PlaylistScreenState extends ConsumerState<PlaylistScreen> {
       final playlistInfo = result['playlist_info'] as Map<String, dynamic>?;
       final owner = playlistInfo?['owner'] as Map<String, dynamic>?;
 
-      // Go backend returns 'track_list' not 'tracks'
       final trackList = result['track_list'] as List<dynamic>? ?? [];
       final tracks = trackList
           .map((t) => _parseTrack(t as Map<String, dynamic>))
@@ -182,14 +181,11 @@ class _PlaylistScreenState extends ConsumerState<PlaylistScreen> {
     return (mediaSize.height * 0.55).clamp(360.0, 520.0);
   }
 
-  /// Upgrade cover URL to a reasonable resolution for full-screen display.
   String? _highResCoverUrl(String? url) {
     if (url == null) return null;
-    // Spotify CDN: upgrade 300 → 640 only
     if (url.contains('ab67616d00001e02')) {
       return url.replaceAll('ab67616d00001e02', 'ab67616d0000b273');
     }
-    // Deezer CDN: upgrade to 1000x1000
     final deezerRegex = RegExp(r'/(\d+)x(\d+)-(\d+)-(\d+)-(\d+)-(\d+)\.jpg$');
     if (url.contains('cdn-images.dzcdn.net') && deezerRegex.hasMatch(url)) {
       return url.replaceAllMapped(
@@ -729,7 +725,6 @@ class _PlaylistScreenState extends ConsumerState<PlaylistScreen> {
   }
 }
 
-/// Separate Consumer widget for each track - only rebuilds when this specific track's status changes
 class _PlaylistTrackItem extends ConsumerWidget {
   final Track track;
   final VoidCallback onDownload;

lib/screens/queue_tab.dart

@@ -156,7 +156,6 @@ class UnifiedLibraryItem {
     return 'builtin:$id';
   }
 
-  /// Convert to a [Track] for adding to collections/playlists.
   Track toTrack() {
     if (historyItem != null) {
       final h = historyItem!;
@@ -2101,7 +2100,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
         }
       }
 
-      // Reload local library if we deleted any local items
       if (allItems.any(
         (i) =>
             _selectedIds.contains(i.id) && i.source == LibraryItemSource.local,
@@ -2121,7 +2119,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     }
   }
 
-  /// Strip EXISTS: prefix from file path (legacy history items)
   String _cleanFilePath(String? filePath) {
     return DownloadedEmbeddedCoverResolver.cleanFilePath(filePath);
   }
@@ -2971,7 +2968,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     }
   }
 
-  /// Navigate with unfocus pattern — unfocuses search before and after navigation.
   void _navigateWithUnfocus(Route<dynamic> route) {
     _searchFocusNode.unfocus();
     Navigator.of(context).push(route).then((_) => _searchFocusNode.unfocus());
@@ -3201,14 +3197,12 @@ class _QueueTabState extends ConsumerState<QueueTab> {
   }) async {
     final notifier = ref.read(libraryCollectionsProvider.notifier);
 
-    // If in selection mode and the dragged item is selected, add ALL selected
     if (_isSelectionMode &&
         _selectedIds.isNotEmpty &&
         _selectedIds.contains(item.id)) {
       final selectedItems = allItems
           .where((e) => _selectedIds.contains(e.id))
           .toList();
-      // Fallback: if allItems is empty or no match, at least add the dragged item
       if (selectedItems.isEmpty) {
         selectedItems.add(item);
       }
@@ -3247,8 +3241,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     );
   }
 
-  /// Build a compact floating feedback widget shown while dragging a track.
-  /// Shows the count when multiple tracks are selected and being dragged.
   Widget _buildDragFeedback(
     BuildContext context,
     UnifiedLibraryItem item,
@@ -3777,7 +3769,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     );
   }
 
-  /// Build a Spotify-style collection list item (Wishlist, Loved, Playlists)
   Widget _buildCollectionListItem({
     required BuildContext context,
     required ColorScheme colorScheme,
@@ -3854,7 +3845,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     );
   }
 
-  /// Build a collection grid item for grid view mode
   Widget _buildCollectionGridItem({
     required BuildContext context,
     required ColorScheme colorScheme,
@@ -3937,7 +3927,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     return entries;
   }
 
-  /// Build a collection item for the unified "All" tab grid view.
   Widget _buildAllTabGridCollectionItem({
     required BuildContext context,
     required ColorScheme colorScheme,
@@ -4055,7 +4044,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     }
   }
 
-  /// Build a collection item for the unified "All" tab list view.
   Widget _buildAllTabListCollectionItem({
     required BuildContext context,
     required ColorScheme colorScheme,
@@ -4208,8 +4196,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
             ),
           ),
 
-        // Collection folders as list items (Spotify-style) in "All" tab
-        // are now rendered inline with tracks below (unified sliver)
         if ((filteredGroupedAlbums.isNotEmpty ||
                 filteredGroupedLocalAlbums.isNotEmpty) &&
             filterMode == 'albums')
@@ -4696,7 +4682,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     );
   }
 
-  /// Album grid item for local library albums
   Widget _buildLocalAlbumGridItem(
     BuildContext context,
     _GroupedLocalAlbum album,
@@ -5275,7 +5260,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
       return;
     }
 
-    // Share SAF content URIs via native intent
     if (safUris.isNotEmpty) {
       try {
         if (safUris.length == 1) {
@@ -5286,7 +5270,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
       } catch (_) {}
     }
 
-    // Share regular files via SharePlus
     if (filesToShare.isNotEmpty) {
       await SharePlus.instance.share(ShareParams(files: filesToShare));
     }
@@ -6400,7 +6383,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     }
   }
 
-  /// Reusable filter button with badge showing active filter count.
   Widget _buildFilterButton(
     BuildContext context,
     List<UnifiedLibraryItem> unifiedItems,
@@ -6495,7 +6477,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
       }
     }
 
-    // Network URL cover (downloaded items)
     if (item.coverUrl != null) {
       return ClipRRect(
         borderRadius: BorderRadius.circular(8),
@@ -6513,7 +6494,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
       );
     }
 
-    // Local file cover (from library scan)
     if (item.localCoverPath != null && item.localCoverPath!.isNotEmpty) {
       return ClipRRect(
         borderRadius: BorderRadius.circular(8),
@@ -6530,7 +6510,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
       );
     }
 
-    // Placeholder (no cover)
     if (size != null) {
       return buildPlaceholder();
     }
@@ -6540,7 +6519,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     );
   }
 
-  /// Build a unified library item (merged downloaded + local)
   Widget _buildUnifiedLibraryItem(
     BuildContext context,
     UnifiedLibraryItem item,
@@ -6748,7 +6726,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     );
   }
 
-  /// Build unified grid item for grid view mode
   Widget _buildUnifiedGridItem(
     BuildContext context,
     UnifiedLibraryItem item,
@@ -7038,7 +7015,6 @@ class _FilterChip extends StatelessWidget {
   }
 }
 
-/// Reusable action button for selection mode bottom bar
 class _SelectionActionButton extends StatelessWidget {
   final IconData icon;
   final String label;

lib/screens/settings/library_settings_page.dart

@@ -53,10 +53,8 @@ class _LibrarySettingsPageState extends ConsumerState<LibrarySettingsPage> {
       if (mounted) {
         setState(() {
           _androidSdkVersion = sdkVersion;
-          // SAF doesn't need storage permission on Android 10+
           _hasStoragePermission = sdkVersion >= 29 ? true : false;
         });
-        // For older Android, check legacy storage permission
         if (sdkVersion < 29) {
           final hasPermission = await Permission.storage.isGranted;
           if (mounted) {
@@ -65,7 +63,6 @@ class _LibrarySettingsPageState extends ConsumerState<LibrarySettingsPage> {
         }
       }
     } else if (Platform.isIOS) {
-      // iOS doesn't need explicit storage permission for app documents
       setState(() => _hasStoragePermission = true);
     } else {
       setState(() => _hasStoragePermission = true);
@@ -74,7 +71,6 @@ class _LibrarySettingsPageState extends ConsumerState<LibrarySettingsPage> {
 
   Future<bool> _requestStoragePermission() async {
     if (!Platform.isAndroid) return true;
-    // SAF on Android 10+ doesn't need MANAGE_EXTERNAL_STORAGE
     if (_androidSdkVersion >= 29) return true;
 
     final status = await Permission.storage.request();
@@ -125,12 +121,9 @@ class _LibrarySettingsPageState extends ConsumerState<LibrarySettingsPage> {
         final granted = await _requestStoragePermission();
         if (!granted) return;
       }
-      // Fallback for older devices
       final result = await FilePicker.platform.getDirectoryPath();
       if (result != null) {
         if (Platform.isIOS) {
-          // On iOS, create a security-scoped bookmark so we can access
-          // this folder across app restarts and from the Go backend.
           final bookmark = await PlatformBridge.createIosBookmarkFromPath(
             result,
           );
@@ -139,8 +132,6 @@ class _LibrarySettingsPageState extends ConsumerState<LibrarySettingsPage> {
                 .read(settingsProvider.notifier)
                 .setLocalLibraryPathAndBookmark(result, bookmark);
           } else {
-            // Bookmark creation failed; save path anyway (works for
-            // app-internal folders like Documents/).
             ref.read(settingsProvider.notifier).setLocalLibraryPath(result);
           }
         } else {
@@ -162,13 +153,7 @@ class _LibrarySettingsPageState extends ConsumerState<LibrarySettingsPage> {
       return;
     }
 
-    // On iOS with a bookmark, try resolving the bookmark first to validate
-    // access instead of checking the path directly (which may fail outside
-    // the app sandbox).
     if (Platform.isIOS && iosBookmark.isNotEmpty) {
-      // Bookmark will be resolved inside startScan; skip Directory.exists
-      // check since security-scoped paths are not accessible without the
-      // bookmark being activated.
     } else if (!libraryPath.startsWith('content://') &&
         !await Directory(libraryPath).exists()) {
       if (mounted) {
@@ -467,7 +452,6 @@ class _LibrarySettingsPageState extends ConsumerState<LibrarySettingsPage> {
             ),
           ),
 
-          // Scan Actions Section
           if (settings.localLibraryEnabled) ...[
             SliverToBoxAdapter(
               child: SettingsSectionHeader(title: context.l10n.libraryActions),

lib/screens/tutorial_screen.dart

@@ -707,10 +707,6 @@ class _TutorialPage extends StatelessWidget {
     final contentGap = (56 * scale) + ((textScale - 1) * 10);
     final bottomGap = (32 * scale).clamp(20.0, 32.0);
 
-    // Parallax effect logic (simplified for StatelessWidget)
-    // In a real advanced implementation we'd pass the Controller's listenable
-    // But for now, let's use entrance animations based on currentIndex == index
-
     final isActive = currentIndex == index;
 
     return SingleChildScrollView(

lib/services/cover_cache_manager.dart

@@ -21,7 +21,6 @@ class CoverCacheManager {
 
   static CacheManager get instance {
     if (!_initialized || _instance == null) {
-      // Fallback to default cache manager if not initialized
       debugPrint('CoverCacheManager: Not initialized, using DefaultCacheManager');
       return DefaultCacheManager();
     }
@@ -36,13 +35,13 @@ class CoverCacheManager {
     try {
       final appDir = await getApplicationSupportDirectory();
       _cachePath = p.join(appDir.path, 'cover_cache');
-      
+
       await Directory(_cachePath!).create(recursive: true);
-      
+
       debugPrint('CoverCacheManager: Initializing at $_cachePath');
 
       _instance = _createManager(_cachePath!);
-      
+
       _initialized = true;
       debugPrint('CoverCacheManager: Initialized successfully');
     } catch (e) {
@@ -60,22 +59,18 @@ class CoverCacheManager {
 
     if (instance == null || cachePath == null) return;
 
-    // Ask cache manager to clear indexed entries first.
     try {
       await instance.emptyCache();
     } catch (e) {
       debugPrint('CoverCacheManager: emptyCache failed, fallback to wipe: $e');
     }
 
-    // Then wipe the directory to remove orphaned files/metadata leftovers.
     await _wipeDirectory(cachePath);
 
-    // Clear in-memory image cache so cleared covers are not retained in RAM.
     final imageCache = PaintingBinding.instance.imageCache;
     imageCache.clear();
     imageCache.clearLiveImages();
 
-    // Reset manager memory/index state after on-disk wipe.
     instance.store.emptyMemoryCache();
     _instance = _createManager(cachePath);
     _initialized = true;
@@ -124,7 +119,6 @@ class CoverCacheManager {
         _cacheKey,
         stalePeriod: _maxCacheAge,
         maxNrOfCacheObjects: _maxCacheObjects,
-        // Use path only (not databaseName) to store database in persistent directory
         repo: JsonCacheInfoRepository(path: cachePath),
         fileSystem: IOFileSystem(cachePath),
         fileService: HttpFileService(),

lib/services/ffmpeg_service.dart

@@ -1350,7 +1350,6 @@ class FFmpegService {
       return null;
     }
 
-    // Lossless targets: dedicated single-pass methods
     if (format == 'alac') {
       return _convertToAlac(
         inputPath: inputPath,
@@ -1369,7 +1368,6 @@ class FFmpegService {
       );
     }
 
-    // Lossy targets: MP3 / Opus
     final extension = format == 'opus' ? '.opus' : '.mp3';
     final outputPath = _buildOutputPath(inputPath, extension);
 
@@ -1966,7 +1964,6 @@ class FFmpegService {
   }
 }
 
-/// Track info for CUE splitting, passed from the CUE parser
 class CueSplitTrackInfo {
   final int number;
   final String title;

lib/services/history_database.dart

@@ -9,10 +9,8 @@ import 'package:spotiflac_android/utils/logger.dart';
 final _log = AppLogger('HistoryDatabase');
 final Future<SharedPreferences> _prefs = SharedPreferences.getInstance();
 
-/// Cached current iOS container path for path normalization
 String? _currentContainerPath;
 
-/// Provides O(1) lookups by spotify_id and isrc with proper indexing
 class HistoryDatabase {
   static final HistoryDatabase instance = HistoryDatabase._init();
   static Database? _database;
@@ -102,21 +100,16 @@ class HistoryDatabase {
     }
   }
 
-  /// Pattern to match iOS container paths
-  /// Example: /var/mobile/Containers/Data/Application/UUID-HERE/Documents/...
   static final _iosContainerPattern = RegExp(
     r'/var/mobile/Containers/Data/Application/[A-F0-9\-]+/',
     caseSensitive: false,
   );
 
-  /// Initialize and cache the current iOS container path
   Future<void> _initContainerPath() async {
     if (!Platform.isIOS || _currentContainerPath != null) return;
 
     try {
       final docDir = await getApplicationDocumentsDirectory();
-      // Extract container path up to and including the UUID folder
-      // e.g., /var/mobile/Containers/Data/Application/UUID/
       final match = _iosContainerPattern.firstMatch(docDir.path);
       if (match != null) {
         _currentContainerPath = match.group(0);
@@ -127,13 +120,10 @@ class HistoryDatabase {
     }
   }
 
-  /// Normalize iOS file path by replacing old container UUID with current one
-  /// This fixes the issue where iOS changes container UUID after app updates
   String _normalizeIosPath(String? filePath) {
     if (filePath == null || filePath.isEmpty) return filePath ?? '';
     if (!Platform.isIOS || _currentContainerPath == null) return filePath;
 
-    // Check if path contains an iOS container path
     if (_iosContainerPattern.hasMatch(filePath)) {
       final normalized = filePath.replaceFirst(
         _iosContainerPattern,
@@ -148,8 +138,6 @@ class HistoryDatabase {
     return filePath;
   }
 
-  /// Migrate iOS paths in database to use current container UUID
-  /// This is called once after app update if container changed
   Future<bool> migrateIosContainerPaths() async {
     if (!Platform.isIOS) return false;
 
@@ -205,8 +193,6 @@ class HistoryDatabase {
     }
   }
 
-  /// Migrate data from SharedPreferences to SQLite
-  /// Returns true if migration was performed, false if already migrated
   Future<bool> migrateFromSharedPreferences() async {
     final prefs = await _prefs;
     final migrationKey = 'history_migrated_to_sqlite';
@@ -243,7 +229,6 @@ class HistoryDatabase {
 
       await batch.commit(noResult: true);
 
-      // Mark as migrated but keep old data for safety
       await prefs.setBool(migrationKey, true);
       _log.i('Migration complete: ${jsonList.length} items');
 
@@ -254,7 +239,6 @@ class HistoryDatabase {
     }
   }
 
-  /// Convert JSON format (camelCase) to DB row (snake_case)
   Map<String, dynamic> _jsonToDbRow(Map<String, dynamic> json) {
     return {
       'id': json['id'],
@@ -286,8 +270,6 @@ class HistoryDatabase {
     };
   }
 
-  /// Convert DB row (snake_case) to JSON format (camelCase)
-  /// Also normalizes iOS paths if container UUID changed
   Map<String, dynamic> _dbRowToJson(Map<String, dynamic> row) {
     return {
       'id': row['id'],
@@ -342,7 +324,6 @@ class HistoryDatabase {
     await batch.commit(noResult: true);
   }
 
-  /// Get all history items ordered by download date (newest first)
   Future<List<Map<String, dynamic>>> getAll({int? limit, int? offset}) async {
     final db = await database;
     final rows = await db.query(
@@ -366,7 +347,6 @@ class HistoryDatabase {
     return _dbRowToJson(rows.first);
   }
 
-  /// Get item by Spotify ID - O(1) with index
   Future<Map<String, dynamic>?> getBySpotifyId(String spotifyId) async {
     final db = await database;
     final rows = await db.query(
@@ -379,7 +359,6 @@ class HistoryDatabase {
     return _dbRowToJson(rows.first);
   }
 
-  /// Get item by ISRC - O(1) with index
   Future<Map<String, dynamic>?> getByIsrc(String isrc) async {
     final db = await database;
     final rows = await db.query(
@@ -392,7 +371,6 @@ class HistoryDatabase {
     return _dbRowToJson(rows.first);
   }
 
-  /// Check if spotify_id exists - O(1) with index
   Future<bool> existsBySpotifyId(String spotifyId) async {
     final db = await database;
     final result = await db.rawQuery(
@@ -402,7 +380,6 @@ class HistoryDatabase {
     return result.isNotEmpty;
   }
 
-  /// Get all spotify_ids as Set for fast in-memory lookup
   Future<Set<String>> getAllSpotifyIds() async {
     final db = await database;
     final rows = await db.rawQuery(
@@ -433,7 +410,6 @@ class HistoryDatabase {
     return Sqflite.firstIntValue(result) ?? 0;
   }
 
-  /// Find existing item by spotify_id or isrc (for deduplication)
   Future<Map<String, dynamic>?> findExisting({
     String? spotifyId,
     String? isrc,
@@ -442,7 +418,6 @@ class HistoryDatabase {
       final bySpotify = await getBySpotifyId(spotifyId);
       if (bySpotify != null) return bySpotify;
 
-      // Check for deezer: prefix matching
       if (spotifyId.startsWith('deezer:')) {
         final deezerId = spotifyId.substring(7);
         final db = await database;
@@ -469,7 +444,6 @@ class HistoryDatabase {
     _database = null;
   }
 
-  /// Update file path for a history entry (e.g. after format conversion)
   Future<void> updateFilePath(
     String id,
     String newFilePath, {
@@ -524,8 +498,6 @@ class HistoryDatabase {
     await db.update('history', values, where: 'id = ?', whereArgs: [id]);
   }
 
-  /// Get all file paths from download history
-  /// Used to exclude downloaded files from local library scan
   Future<Set<String>> getAllFilePaths() async {
     final db = await database;
     final rows = await db.rawQuery(
@@ -534,8 +506,6 @@ class HistoryDatabase {
     return rows.map((r) => r['file_path'] as String).toSet();
   }
 
-  /// Get all entries with file paths for orphan detection
-  /// Returns list of (id, file_path, storage_mode, download_tree_uri, saf_relative_dir, saf_file_name)
   Future<List<Map<String, dynamic>>> getAllEntriesWithPaths() async {
     final db = await database;
     final rows = await db.rawQuery('''
@@ -569,7 +539,6 @@ class HistoryDatabase {
     return rows.map((r) => Map<String, dynamic>.from(r)).toList();
   }
 
-  /// Delete multiple entries by IDs
   Future<int> deleteByIds(List<String> ids) async {
     if (ids.isEmpty) return 0;
 

lib/services/library_database.dart

@@ -96,7 +96,6 @@ class LocalLibraryItem {
         format: json['format'] as String?,
       );
 
-  /// Create a unique key for matching tracks
   String get matchKey =>
       '${trackName.toLowerCase()}|${artistName.toLowerCase()}';
   String get albumKey =>
@@ -183,13 +182,11 @@ class LibraryDatabase {
     }
 
     if (oldVersion < 3) {
-      // Add file_mod_time column for incremental scanning
       await db.execute('ALTER TABLE library ADD COLUMN file_mod_time INTEGER');
       _log.i('Added file_mod_time column for incremental scanning');
     }
 
     if (oldVersion < 4) {
-      // Add bitrate column for lossy format quality info
       await db.execute('ALTER TABLE library ADD COLUMN bitrate INTEGER');
       _log.i('Added bitrate column for lossy format quality');
     }
@@ -475,8 +472,6 @@ class LibraryDatabase {
     _database = null;
   }
 
-  /// Get all file paths with their modification times for incremental scanning
-  /// Returns a map of filePath -> fileModTime (unix timestamp in milliseconds)
   Future<Map<String, int>> getFileModTimes() async {
     final db = await database;
     final rows = await db.rawQuery(
@@ -491,8 +486,6 @@ class LibraryDatabase {
     return result;
   }
 
-  /// Export file modification times to a compact line-based snapshot that
-  /// native code can read without receiving a large method-channel payload.
   Future<String> writeFileModTimesSnapshot() async {
     final db = await database;
     final rows = await db.rawQuery(
@@ -519,7 +512,6 @@ class LibraryDatabase {
     return file.path;
   }
 
-  /// Update file_mod_time for existing rows using file_path as key.
   Future<void> updateFileModTimes(Map<String, int> fileModTimes) async {
     if (fileModTimes.isEmpty) return;
     final db = await database;
@@ -535,7 +527,6 @@ class LibraryDatabase {
     await batch.commit(noResult: true);
   }
 
-  /// Get all file paths in the library (for detecting deleted files)
   Future<Set<String>> getAllFilePaths() async {
     final db = await database;
     final rows = await db.rawQuery('SELECT file_path FROM library');

lib/services/platform_bridge.dart

@@ -422,6 +422,21 @@ class PlatformBridge {
     return jsonDecode(result as String) as Map<String, dynamic>;
   }
 
+  /// Rewrites ARTIST/ALBUMARTIST Vorbis comments as multiple split entries
+  /// using the native Go FLAC writer, fixing FFmpeg's tag deduplication.
+  static Future<Map<String, dynamic>> rewriteSplitArtistTags(
+    String filePath,
+    String artist,
+    String albumArtist,
+  ) async {
+    final result = await _channel.invokeMethod('rewriteSplitArtistTags', {
+      'file_path': filePath,
+      'artist': artist,
+      'album_artist': albumArtist,
+    });
+    return jsonDecode(result as String) as Map<String, dynamic>;
+  }
+
   static Future<bool> writeTempToSaf(String tempPath, String safUri) async {
     final result = await _channel.invokeMethod('writeTempToSaf', {
       'temp_path': tempPath,

lib/services/share_intent_service.dart

@@ -10,7 +10,6 @@ class ShareIntentService {
   factory ShareIntentService() => _instance;
   ShareIntentService._internal();
 
-  // Spotify patterns
   static final RegExp _spotifyUriPattern = RegExp(
     r'spotify:(track|album|playlist|artist):[a-zA-Z0-9]+',
   );
@@ -18,7 +17,6 @@ class ShareIntentService {
     r'https?://open\.spotify\.com/(track|album|playlist|artist)/[a-zA-Z0-9]+(\?[^\s]*)?',
   );
 
-  // Deezer patterns
   static final RegExp _deezerUrlPattern = RegExp(
     r'https?://(www\.)?deezer\.com/(track|album|playlist|artist)/\d+(\?[^\s]*)?',
   );
@@ -26,17 +24,14 @@ class ShareIntentService {
     r'https?://deezer\.page\.link/[a-zA-Z0-9]+',
   );
 
-  // Tidal patterns
   static final RegExp _tidalUrlPattern = RegExp(
     r'https?://(listen\.)?tidal\.com/(track|album|playlist|artist)/[a-zA-Z0-9-]+(\?[^\s]*)?',
   );
 
-  // YouTube Music patterns
   static final RegExp _ytMusicUrlPattern = RegExp(
     r'https?://music\.youtube\.com/(watch\?v=|playlist\?list=|channel/|browse/)[a-zA-Z0-9_-]+([?&][^\s]*)?',
   );
 
-  // Standard YouTube patterns (youtu.be short links and www.youtube.com/watch)
   static final RegExp _youtubeUrlPattern = RegExp(
     r'https?://(youtu\.be/[a-zA-Z0-9_-]+|www\.youtube\.com/watch\?v=[a-zA-Z0-9_-]+)([?&][^\s]*)?',
   );
@@ -117,7 +112,6 @@ class ShareIntentService {
       final match = pattern.firstMatch(text);
       if (match != null) {
         final fullUrl = match.group(0)!;
-        // Keep query params for YouTube URLs (needed for ?v=, ?list=, etc.)
         if (pattern == _ytMusicUrlPattern || pattern == _youtubeUrlPattern) {
           return fullUrl;
         }

lib/theme/app_theme.dart

@@ -3,7 +3,6 @@ import 'package:flutter/services.dart';
 import 'package:spotiflac_android/models/theme_settings.dart';
 
 class AppTheme {
-  /// Default seed color (Spotify green)
   static const Color defaultSeedColor = Color(kDefaultSeedColor);
 
   static ThemeData light({ColorScheme? dynamicScheme, Color? seedColor}) {
@@ -87,12 +86,10 @@ class AppTheme {
       fontWeight: FontWeight.w500,
     ),
     systemOverlayStyle: SystemUiOverlayStyle(
-      // Status bar
       statusBarColor: Colors.transparent,
       statusBarIconBrightness: scheme.brightness == Brightness.dark
           ? Brightness.light
           : Brightness.dark,
-      // System navigation bar — match the in-app NavigationBar color
       systemNavigationBarColor: isAmoled
           ? Colors.black
           : scheme.surfaceContainer,

lib/utils/clickable_metadata.dart

@@ -11,11 +11,6 @@ import 'package:spotiflac_android/utils/logger.dart';
 
 final _log = AppLogger('ClickableMetadata');
 
-/// Navigate to an artist screen by searching Deezer for the artist ID.
-///
-/// If [artistId] is provided and valid, navigates directly.
-/// Otherwise, searches Deezer by [artistName] to resolve the ID first.
-/// For extension-based content, pass [extensionId] to use ExtensionArtistScreen.
 Future<void> navigateToArtist(
   BuildContext context, {
   required String artistName,
@@ -95,11 +90,6 @@ Future<void> navigateToArtist(
   }
 }
 
-/// Navigate to an album screen by searching Deezer for the album ID.
-///
-/// If [albumId] is provided and valid, navigates directly.
-/// Otherwise, searches Deezer by [albumName] (optionally with [artistName]) to resolve the ID.
-/// For extension-based content, pass [extensionId] to use ExtensionAlbumScreen.
 Future<void> navigateToAlbum(
   BuildContext context, {
   required String albumName,
@@ -217,9 +207,6 @@ void _pushAlbumScreen(
   String? coverUrl,
   String? extensionId,
 }) {
-  // Built-in providers (tidal, qobuz, deezer) use AlbumScreen which
-  // detects the provider from the album ID prefix. Only true JS extensions
-  // should use ExtensionAlbumScreen.
   const builtInProviders = {'tidal', 'qobuz', 'deezer'};
   final isExtension =
       extensionId != null && !builtInProviders.contains(extensionId);
@@ -297,10 +284,6 @@ void _showUnavailable(BuildContext context, String type) {
   ).showSnackBar(SnackBar(content: Text('$type information not available')));
 }
 
-/// A reusable widget that makes text tappable to navigate to an artist screen.
-///
-/// Wraps the text in a GestureDetector that, when tapped, looks up the artist
-/// via Deezer search and navigates to the ArtistScreen.
 class ClickableArtistName extends StatefulWidget {
   final String artistName;
   final String? artistId;
@@ -526,10 +509,6 @@ bool _canNavigateArtistDirectly({
 
 final RegExp _spotifyArtistIdPattern = RegExp(r'^[A-Za-z0-9]{22}$');
 
-/// A reusable widget that makes text tappable to navigate to an album screen.
-///
-/// Wraps the text in a GestureDetector that, when tapped, looks up the album
-/// via Deezer search and navigates to the AlbumScreen.
 class ClickableAlbumName extends StatelessWidget {
   final String albumName;
   final String? albumId;

lib/utils/file_access.dart

@@ -47,26 +47,20 @@ bool isValidIosWritablePath(String path) {
   if (path.isEmpty) return false;
   if (!path.startsWith('/')) return false;
 
-  // Check if it's the container root (without Documents/, tmp/, etc.)
   if (_iosContainerRootPattern.hasMatch(path)) {
     return false;
   }
 
-  // Check for iCloud Drive paths
   if (path.contains('Mobile Documents') ||
       path.contains('CloudDocs') ||
       path.contains('com~apple~CloudDocs')) {
     return false;
   }
 
-  // Reject stale paths where an old sandbox container path has been embedded
-  // inside the current Documents directory.
   if (_iosNestedLegacyDocumentsPattern.hasMatch(path)) {
     return false;
   }
 
-  // Ensure path contains a valid subdirectory (Documents, tmp, Library, etc.)
-  // This handles cases where FilePicker returns container root
   final containerPattern = RegExp(
     r'/var/mobile/Containers/Data/Application/[A-F0-9\-]+',
     caseSensitive: false,
@@ -74,7 +68,6 @@ bool isValidIosWritablePath(String path) {
   final match = containerPattern.firstMatch(path);
   if (match != null) {
     final remainingPath = path.substring(match.end);
-    // Valid paths should have something after the UUID
     if (remainingPath.isEmpty || remainingPath == '/') {
       return false;
     }
@@ -111,13 +104,10 @@ Future<String> validateOrFixIosPath(
     candidates.add(trimmed);
   }
 
-  // Some pickers can return absolute iOS paths without the leading slash.
   if (_iosContainerPathWithoutLeadingSlashPattern.hasMatch(trimmed)) {
     candidates.add('/$trimmed');
   }
 
-  // Recover legacy relative iOS path format:
-  // Data/Application/<UUID>/Documents/<subdir>
   final legacyRelativeMatch = _iosLegacyRelativeDocumentsPattern.firstMatch(
     trimmed,
   );
@@ -127,7 +117,6 @@ Future<String> validateOrFixIosPath(
     );
   }
 
-  // Generic salvage for relative paths containing `Documents/...`.
   if (!trimmed.startsWith('/')) {
     final documentsMarker = 'Documents/';
     final index = trimmed.indexOf(documentsMarker);
@@ -143,7 +132,6 @@ Future<String> validateOrFixIosPath(
     }
   }
 
-  // Fall back to app Documents directory
   final musicDir = Directory('${docDir.path}/$subfolder');
   if (!await musicDir.exists()) {
     await musicDir.create(recursive: true);
@@ -185,7 +173,6 @@ IosPathValidationResult validateIosPath(String path) {
     );
   }
 
-  // Check if it's the container root
   if (_iosContainerRootPattern.hasMatch(path)) {
     return const IosPathValidationResult(
       isValid: false,
@@ -194,7 +181,6 @@ IosPathValidationResult validateIosPath(String path) {
     );
   }
 
-  // Check for iCloud Drive paths
   if (path.contains('Mobile Documents') ||
       path.contains('CloudDocs') ||
       path.contains('com~apple~CloudDocs')) {
@@ -213,7 +199,6 @@ IosPathValidationResult validateIosPath(String path) {
     );
   }
 
-  // Check for container root without subdirectory
   final containerPattern = RegExp(
     r'/var/mobile/Containers/Data/Application/[A-F0-9\-]+',
     caseSensitive: false,
@@ -263,7 +248,6 @@ String stripCueTrackSuffix(String path) {
 
 Future<bool> fileExists(String? path) async {
   if (path == null || path.isEmpty) return false;
-  // For CUE virtual paths, check if the base .cue file exists
   final realPath = isCueVirtualPath(path) ? stripCueTrackSuffix(path) : path;
   if (isContentUri(realPath)) {
     return PlatformBridge.safExists(realPath);
@@ -288,7 +272,6 @@ Future<void> deleteFile(String? path) async {
 
 Future<FileAccessStat?> fileStat(String? path) async {
   if (path == null || path.isEmpty) return null;
-  // For CUE virtual paths, stat the base .cue file
   final realPath = isCueVirtualPath(path) ? stripCueTrackSuffix(path) : path;
   if (isContentUri(realPath)) {
     final stat = await PlatformBridge.safStat(realPath);

lib/utils/path_match_keys.dart

@@ -25,9 +25,6 @@ const _audioExtensions = <String>[
 const _maxPathMatchKeyCacheSize = 6000;
 final Map<String, Set<String>> _pathMatchKeyCache = <String, Set<String>>{};
 
-/// Strips a trailing audio extension from [path] if present.
-/// Returns the path without extension, or `null` if no known audio extension
-/// was found.
 String? _stripAudioExtension(String path) {
   final lower = path.toLowerCase();
   for (final ext in _audioExtensions) {
@@ -115,8 +112,6 @@ Set<String> buildPathMatchKeys(String? filePath) {
 
   addNormalized(cleaned);
 
-  // Add extension-stripped variants so that a file converted from one audio
-  // format to another (e.g. Song.flac → Song.opus) still matches.
   final extensionStrippedKeys = <String>{};
   for (final key in keys) {
     final stripped = _stripAudioExtension(key);

lib/widgets/animation_utils.dart

@@ -1,9 +1,5 @@
 import 'package:flutter/material.dart';
 
-// ─────────────────────────────────────────────────────────────────────────────
-// 1. Staggered List Item – fade + slide-up entrance with index-based delay
-// ─────────────────────────────────────────────────────────────────────────────
-
 /// Wraps a child in a staggered fade-in + slide-up animation.
 ///
 /// [index] controls the stagger delay (each item delayed by [staggerDelay]).
@@ -31,7 +27,6 @@ class StaggeredListItem extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     if (!animate || index >= maxAnimatedItems) return child;
-    // Cap the delay so very long lists don't have absurd wait times.
     final cappedIndex = index.clamp(0, maxAnimatedItems - 1);
     final delay = staggerDelay * cappedIndex;
     final totalDuration = duration + delay;
@@ -42,7 +37,6 @@ class StaggeredListItem extends StatelessWidget {
       duration: totalDuration,
       curve: Curves.easeOutCubic,
       builder: (context, value, child) {
-        // Compute the effective progress after the stagger delay.
         final delayFraction = totalDuration.inMilliseconds > 0
             ? delay.inMilliseconds / totalDuration.inMilliseconds
             : 0.0;
@@ -62,10 +56,6 @@ class StaggeredListItem extends StatelessWidget {
   }
 }
 
-// ─────────────────────────────────────────────────────────────────────────────
-// 2. Animated State Switcher – crossfade between loading / content / empty / error
-// ─────────────────────────────────────────────────────────────────────────────
-
 /// A convenience wrapper around [AnimatedSwitcher] that crossfades between
 /// different widget states (loading, content, empty, error).
 ///
@@ -94,10 +84,6 @@ class AnimatedStateSwitcher extends StatelessWidget {
   }
 }
 
-// ─────────────────────────────────────────────────────────────────────────────
-// 3. Shared Page Route – consistent slide-from-right transition
-// ─────────────────────────────────────────────────────────────────────────────
-
 /// Creates a platform-aware material route.
 ///
 /// This intentionally defers route transitions to Flutter's material route and
@@ -107,10 +93,6 @@ Route<T> slidePageRoute<T>({required Widget page}) {
   return MaterialPageRoute<T>(builder: (context) => page);
 }
 
-// ─────────────────────────────────────────────────────────────────────────────
-// 4. Shimmer / Skeleton Loading Widget
-// ─────────────────────────────────────────────────────────────────────────────
-
 /// A shimmer effect widget that can wrap skeleton placeholders.
 class ShimmerLoading extends StatefulWidget {
   final Widget child;
@@ -682,10 +664,6 @@ class HomeSearchSkeleton extends StatelessWidget {
   }
 }
 
-// ─────────────────────────────────────────────────────────────────────────────
-// 5. Animated Selection Checkbox – scales in when entering selection mode
-// ─────────────────────────────────────────────────────────────────────────────
-
 /// An animated selection indicator that scales in/out and crossfades the
 /// checked/unchecked state.
 class AnimatedSelectionCheckbox extends StatelessWidget {
@@ -746,10 +724,6 @@ class AnimatedSelectionCheckbox extends StatelessWidget {
   }
 }
 
-// ─────────────────────────────────────────────────────────────────────────────
-// 6. Download Success Animation – green flash + checkmark
-// ─────────────────────────────────────────────────────────────────────────────
-
 /// A widget that briefly flashes a success color behind its child and shows
 /// an animated checkmark when [showSuccess] transitions to true.
 class DownloadSuccessOverlay extends StatefulWidget {
@@ -775,8 +749,6 @@ class _DownloadSuccessOverlayState extends State<DownloadSuccessOverlay>
   @override
   void initState() {
     super.initState();
-    // Initialise from the current widget value so items that are already
-    // completed when first built do not play the flash animation.
     _wasSuccess = widget.showSuccess;
     _controller = AnimationController(
       vsync: this,
@@ -821,10 +793,6 @@ class _DownloadSuccessOverlayState extends State<DownloadSuccessOverlay>
   }
 }
 
-// ─────────────────────────────────────────────────────────────────────────────
-// 7. Badge Bump Animation – scales the badge when count changes
-// ─────────────────────────────────────────────────────────────────────────────
-
 /// Wraps a [Badge] child and plays a brief scale-bump whenever [count] changes.
 class AnimatedBadge extends StatefulWidget {
   final int count;
@@ -877,10 +845,6 @@ class _AnimatedBadgeState extends State<AnimatedBadge>
   }
 }
 
-// ─────────────────────────────────────────────────────────────────────────────
-// 8. Animated Removal Item – fade + slide out when removed from a list
-// ─────────────────────────────────────────────────────────────────────────────
-
 /// Build a removal animation for [AnimatedList] items.
 /// Use as the `builder` callback in [AnimatedListState.removeItem].
 Widget buildRemovalAnimation(Widget child, Animation<double> animation) {

lib/widgets/batch_progress_dialog.dart

@@ -1,7 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:spotiflac_android/l10n/l10n.dart';
 
-/// Progress state communicated from caller to dialog via [ValueNotifier].
 class _BatchProgress {
   final int current;
   final String? detail;
@@ -54,11 +53,8 @@ class BatchProgressDialog extends StatefulWidget {
     required ValueNotifier<_BatchProgress> progressNotifier,
   }) : _progressNotifier = progressNotifier;
 
-  // ── Static bookkeeping ──────────────────────────────────────────────
-
   static ValueNotifier<_BatchProgress>? _activeNotifier;
 
-  /// Show the dialog. Call [update] to push progress, [dismiss] to close.
   static void show({
     required BuildContext context,
     required String title,
@@ -82,13 +78,10 @@ class BatchProgressDialog extends StatefulWidget {
     );
   }
 
-  /// Update the progress of the currently visible dialog.
-  /// No [BuildContext] needed – communicates via [ValueNotifier].
   static void update({required int current, String? detail}) {
     _activeNotifier?.value = _BatchProgress(current: current, detail: detail);
   }
 
-  /// Dismiss the dialog and clean up.
   static void dismiss(BuildContext context) {
     _activeNotifier = null;
     Navigator.of(context, rootNavigator: true).pop();

lib/widgets/collapsing_header.dart

@@ -1,8 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:spotiflac_android/utils/app_bar_layout.dart';
 
-/// A collapsing header widget
-/// Title collapses from large to small when scrolling
 class CollapsingHeader extends StatelessWidget {
   final String title;
   final bool showBackButton;
@@ -100,7 +98,6 @@ class CollapsingHeader extends StatelessWidget {
   }
 }
 
-/// Section header for settings
 class SettingsSection extends StatelessWidget {
   final String title;
   const SettingsSection({super.key, required this.title});
@@ -120,7 +117,6 @@ class SettingsSection extends StatelessWidget {
   }
 }
 
-/// Info card widget (like version info)
 class InfoCard extends StatelessWidget {
   final IconData icon;
   final String title;

lib/widgets/donate_icons.dart

@@ -1,7 +1,5 @@
 import 'package:flutter/material.dart';
 
-/// Custom painted icons for donate platforms
-
 class KofiIcon extends StatelessWidget {
   final double size;
   final Color color;
@@ -46,7 +44,6 @@ class _KofiPainter extends CustomPainter {
       ..quadraticBezierTo(s * 0.92, s * 0.68, s * 0.70, s * 0.68);
     canvas.drawPath(handlePath, handlePaint);
 
-    // Heart on cup
     final heartPaint = Paint()
       ..color = const Color(0xFFFF5E5B)
       ..style = PaintingStyle.fill;
@@ -62,7 +59,6 @@ class _KofiPainter extends CustomPainter {
       ..close();
     canvas.drawPath(heart, heartPaint);
 
-    // Steam lines
     final steamPaint = Paint()
       ..color = color.withValues(alpha: 0.6)
       ..style = PaintingStyle.stroke
@@ -108,12 +104,9 @@ class _GitHubPainter extends CustomPainter {
       ..color = color
       ..style = PaintingStyle.fill;
 
-    // GitHub octocat silhouette (simplified mark)
-    // Based on the GitHub logo path, scaled to fit
     final scale = s / 24.0;
 
     final path = Path();
-    // Outer circle/head shape
     path.moveTo(12 * scale, 0.5 * scale);
     path.cubicTo(
       5.37 * scale, 0.5 * scale,
@@ -135,7 +128,6 @@ class _GitHubPainter extends CustomPainter {
       9.01 * scale, 22.01 * scale,
       9.01 * scale, 21.01 * scale,
     );
-    // Left arm
     path.cubicTo(
       5.67 * scale, 21.71 * scale,
       4.97 * scale, 19.56 * scale,

lib/widgets/download_service_picker.dart

@@ -5,7 +5,6 @@ import 'package:spotiflac_android/providers/extension_provider.dart';
 import 'package:spotiflac_android/providers/settings_provider.dart';
 import 'package:spotiflac_android/l10n/l10n.dart';
 
-/// Built-in service info with quality options
 class BuiltInService {
   final String id;
   final String label;
@@ -22,7 +21,6 @@ class BuiltInService {
   });
 }
 
-/// Default quality options for each built-in service
 const _builtInServices = [
   BuiltInService(
     id: 'tidal',
@@ -99,7 +97,6 @@ class DownloadServicePicker extends ConsumerStatefulWidget {
   ConsumerState<DownloadServicePicker> createState() =>
       _DownloadServicePickerState();
 
-  /// Show the download service picker as a modal bottom sheet
   static void show(
     BuildContext context, {
     String? trackName,
@@ -135,7 +132,6 @@ class _DownloadServicePickerState extends ConsumerState<DownloadServicePicker> {
   @override
   void initState() {
     super.initState();
-    // Default to recommended service if available, otherwise use default
     final recommended = widget.recommendedService;
     if (recommended != null && recommended.isNotEmpty) {
       _selectedService = recommended;
@@ -144,7 +140,6 @@ class _DownloadServicePickerState extends ConsumerState<DownloadServicePicker> {
     }
   }
 
-  /// Get quality options for the selected service
   List<QualityOption> _getQualityOptions() {
     final builtIn = _builtInServices
         .where((s) => s.id == _selectedService)
@@ -161,8 +156,6 @@ class _DownloadServicePickerState extends ConsumerState<DownloadServicePicker> {
       return ext.qualityOptions;
     }
 
-    // Extensions without quality options use Tidal's options as default
-    // since the download will fall back to built-in providers anyway.
     return _builtInServices.firstWhere((s) => s.id == 'tidal').qualityOptions;
   }
 

lib/widgets/re_enrich_field_dialog.dart

@@ -29,10 +29,6 @@ class ReEnrichFieldSelection {
   bool get isAll => fields.length == ReEnrichFields.all.length;
 }
 
-/// Shows a bottom sheet that lets the user pick which metadata fields to update
-/// during a bulk re-enrich operation.
-///
-/// Returns `null` when cancelled, or a [ReEnrichFieldSelection] when confirmed.
 Future<ReEnrichFieldSelection?> showReEnrichFieldDialog(
   BuildContext context, {
   required int selectedCount,
@@ -128,7 +124,6 @@ class _ReEnrichFieldSheetState extends State<_ReEnrichFieldSheet> {
         mainAxisSize: MainAxisSize.min,
         crossAxisAlignment: CrossAxisAlignment.start,
         children: [
-          // Title
           Padding(
             padding: const EdgeInsets.fromLTRB(24, 0, 24, 4),
             child: Text(
@@ -138,7 +133,6 @@ class _ReEnrichFieldSheetState extends State<_ReEnrichFieldSheet> {
               ),
             ),
           ),
-          // Subtitle
           Padding(
             padding: const EdgeInsets.fromLTRB(24, 0, 24, 4),
             child: Text(
@@ -158,7 +152,6 @@ class _ReEnrichFieldSheetState extends State<_ReEnrichFieldSheet> {
             ),
           ),
           const Divider(height: 1),
-          // Select All
           CheckboxListTile(
             contentPadding: const EdgeInsets.symmetric(horizontal: 16),
             title: Text(
@@ -171,7 +164,6 @@ class _ReEnrichFieldSheetState extends State<_ReEnrichFieldSheet> {
             controlAffinity: ListTileControlAffinity.leading,
           ),
           const Divider(height: 1, indent: 16, endIndent: 16),
-          // Individual fields
           for (final field in ReEnrichFields.all)
             CheckboxListTile(
               contentPadding: const EdgeInsets.symmetric(horizontal: 16),
@@ -182,7 +174,6 @@ class _ReEnrichFieldSheetState extends State<_ReEnrichFieldSheet> {
               controlAffinity: ListTileControlAffinity.leading,
             ),
           const SizedBox(height: 8),
-          // Confirm button
           Padding(
             padding: const EdgeInsets.fromLTRB(16, 8, 16, 16),
             child: SizedBox(

lib/widgets/settings_group.dart

@@ -1,7 +1,5 @@
 import 'package:flutter/material.dart';
 
-/// A grouped settings card that connects items together like Android Settings
-/// Items are connected with no gap between them, only separated when changing groups
 class SettingsGroup extends StatelessWidget {
   final List<Widget> children;
   final EdgeInsetsGeometry? margin;
@@ -17,14 +15,10 @@ class SettingsGroup extends StatelessWidget {
     final colorScheme = Theme.of(context).colorScheme;
     final isDark = Theme.of(context).brightness == Brightness.dark;
     
-    // Use a more contrasting color for cards
-    // In dark mode with dynamic color, surfaceContainerHighest can be too similar to surface
-    // So we add a slight white overlay to make it more visible
-    // In light mode with dynamic color, we add a slight black overlay for the same reason
     final cardColor = isDark 
         ? Color.alphaBlend(Colors.white.withValues(alpha: 0.08), colorScheme.surface)
         : Color.alphaBlend(Colors.black.withValues(alpha: 0.04), colorScheme.surface);
-    
+
     return Container(
       margin: margin ?? const EdgeInsets.symmetric(horizontal: 16, vertical: 4),
       decoration: BoxDecoration(
@@ -44,7 +38,6 @@ class SettingsGroup extends StatelessWidget {
 }
 
 class SettingsItem extends StatelessWidget {
-
   final IconData? icon;
   final String title;
   final String? subtitle;
@@ -126,7 +119,6 @@ class SettingsItem extends StatelessWidget {
 }
 
 class SettingsSwitchItem extends StatelessWidget {
-
   final IconData? icon;
   final String title;
   final String? subtitle;
@@ -214,7 +206,6 @@ class SettingsSwitchItem extends StatelessWidget {
 }
 
 class SettingsSectionHeader extends StatelessWidget {
-
   final String title;
 
   const SettingsSectionHeader({super.key, required this.title});

lib/widgets/track_collection_quick_actions.dart

@@ -74,7 +74,6 @@ class _TrackOptionsSheet extends ConsumerWidget {
           child: Column(
             mainAxisSize: MainAxisSize.min,
             children: [
-              // Header with drag handle + track info (matches _TrackInfoHeader)
               Column(
                 children: [
                   const SizedBox(height: 8),
@@ -163,7 +162,6 @@ class _TrackOptionsSheet extends ConsumerWidget {
                 color: colorScheme.outlineVariant.withValues(alpha: 0.5),
               ),
 
-              // Action items (matches _QualityOption style)
               _OptionTile(
                 icon: isLoved ? Icons.favorite : Icons.favorite_border,
                 iconColor: isLoved ? colorScheme.error : null,
@@ -234,7 +232,6 @@ class _TrackOptionsSheet extends ConsumerWidget {
   }
 }
 
-/// Styled like _QualityOption in download_service_picker.dart
 class _OptionTile extends StatelessWidget {
   final IconData icon;
   final Color? iconColor;