refactor: clean up redundant comments and code

go_backend/audio_metadata.go

@@ -54,17 +54,14 @@ func ReadID3Tags(filePath string) (*AudioMetadata, error) {
 
 	metadata := &AudioMetadata{}
 
-	// Try ID3v2 first (at beginning of file)
 	id3v2, err := readID3v2(file)
 	if err == nil && id3v2 != nil {
 		metadata = id3v2
 	}
 
-	// If ID3v2 failed or is incomplete, try ID3v1 (at end of file)
 	if metadata.Title == "" || metadata.Artist == "" {
 		id3v1, err := readID3v1(file)
 		if err == nil && id3v1 != nil {
-			// Fill in missing fields
 			if metadata.Title == "" {
 				metadata.Title = id3v1.Title
 			}
@@ -94,35 +91,28 @@ func ReadID3Tags(filePath string) (*AudioMetadata, error) {
 func readID3v2(file *os.File) (*AudioMetadata, error) {
 	file.Seek(0, io.SeekStart)
 
-	// Read ID3v2 header (10 bytes)
 	header := make([]byte, 10)
 	if _, err := io.ReadFull(file, header); err != nil {
 		return nil, err
 	}
 
-	// Check for "ID3" identifier
 	if string(header[0:3]) != "ID3" {
 		return nil, fmt.Errorf("no ID3v2 header")
 	}
 
-	// Get version
 	majorVersion := header[3]
-	// minorVersion := header[4]
 	flags := header[5]
 	unsync := (flags & 0x80) != 0
 	extendedHeader := (flags & 0x40) != 0
 	footerPresent := (flags & 0x10) != 0
 
-	// Get tag size (syncsafe integer)
 	size := int(header[6])<<21 | int(header[7])<<14 | int(header[8])<<7 | int(header[9])
 
-	// Read all tag data
 	tagData := make([]byte, size)
 	if _, err := io.ReadFull(file, tagData); err != nil {
 		return nil, err
 	}
 
-	// Remove footer if present (10 bytes, starts with "3DI")
 	if footerPresent && len(tagData) >= 10 {
 		footerStart := len(tagData) - 10
 		if footerStart >= 0 && string(tagData[footerStart:footerStart+3]) == "3DI" {
@@ -130,7 +120,6 @@ func readID3v2(file *os.File) (*AudioMetadata, error) {
 		}
 	}
 
-	// Skip extended header if present
 	if extendedHeader {
 		if skip := extendedHeaderSize(tagData, majorVersion); skip > 0 && skip < len(tagData) {
 			tagData = tagData[skip:]
@@ -139,11 +128,9 @@ func readID3v2(file *os.File) (*AudioMetadata, error) {
 
 	metadata := &AudioMetadata{}
 
-	// Parse frames based on version
 	if majorVersion == 2 {
 		parseID3v22Frames(tagData, metadata, unsync)
 	} else {
-		// ID3v2.3 and ID3v2.4
 		parseID3v23Frames(tagData, metadata, majorVersion, unsync)
 	}
 
@@ -156,7 +143,7 @@ func parseID3v22Frames(data []byte, metadata *AudioMetadata, tagUnsync bool) {
 	for pos+6 < len(data) {
 		frameID := string(data[pos : pos+3])
 		if frameID[0] == 0 {
-			break // Padding
+			break
 		}
 
 		frameSize := int(data[pos+3])<<16 | int(data[pos+4])<<8 | int(data[pos+5])
@@ -171,21 +158,21 @@ func parseID3v22Frames(data []byte, metadata *AudioMetadata, tagUnsync bool) {
 		value := firstTextValue(extractTextFrame(frameData))
 
 		switch frameID {
-		case "TT2": // Title
+		case "TT2":
 			metadata.Title = value
-		case "TP1": // Artist
+		case "TP1":
 			metadata.Artist = value
-		case "TP2": // Album Artist
+		case "TP2":
 			metadata.AlbumArtist = value
-		case "TAL": // Album
+		case "TAL":
 			metadata.Album = value
-		case "TYE": // Year
+		case "TYE":
 			metadata.Year = value
-		case "TCO": // Genre
+		case "TCO":
 			metadata.Genre = cleanGenre(value)
-		case "TRK": // Track
+		case "TRK":
 			metadata.TrackNumber = parseTrackNumber(value)
-		case "TPA": // Disc
+		case "TPA":
 			metadata.DiscNumber = parseTrackNumber(value)
 		}
 
@@ -199,7 +186,7 @@ func parseID3v23Frames(data []byte, metadata *AudioMetadata, version byte, tagUn
 	for pos+10 < len(data) {
 		frameID := string(data[pos : pos+4])
 		if frameID[0] == 0 {
-			break // Padding
+			break
 		}
 
 		var frameSize int
@@ -238,7 +225,7 @@ func parseID3v23Frames(data []byte, metadata *AudioMetadata, version byte, tagUn
 					pos += 10 + frameSize
 					continue
 				}
-				frameData = frameData[1:] // skip group ID
+				frameData = frameData[1:]
 			}
 			if tagUnsync {
 				frameData = removeUnsync(frameData)
@@ -246,18 +233,18 @@ func parseID3v23Frames(data []byte, metadata *AudioMetadata, version byte, tagUn
 		} else if version == 4 {
 			// ID3v2.4 format flags: grouping, compression, encryption, unsync, data length indicator
 			const (
-				id3v24FlagGrouping      = 0x40
-				id3v24FlagCompression   = 0x08
-				id3v24FlagEncryption    = 0x04
-				id3v24FlagUnsync        = 0x02
-				id3v24FlagDataLen       = 0x01
+				id3v24FlagGrouping    = 0x40
+				id3v24FlagCompression = 0x08
+				id3v24FlagEncryption  = 0x04
+				id3v24FlagUnsync      = 0x02
+				id3v24FlagDataLen     = 0x01
 			)
 			if formatFlags&id3v24FlagGrouping != 0 {
 				if len(frameData) < 1 {
 					pos += 10 + frameSize
 					continue
 				}
-				frameData = frameData[1:] // skip group ID
+				frameData = frameData[1:]
 			}
 			if formatFlags&id3v24FlagDataLen != 0 {
 				if len(frameData) < 4 {
@@ -278,26 +265,26 @@ func parseID3v23Frames(data []byte, metadata *AudioMetadata, version byte, tagUn
 		value := firstTextValue(extractTextFrame(frameData))
 
 		switch frameID {
-		case "TIT2": // Title
+		case "TIT2":
 			metadata.Title = value
-		case "TPE1": // Artist
+		case "TPE1":
 			metadata.Artist = value
-		case "TPE2": // Album Artist
+		case "TPE2":
 			metadata.AlbumArtist = value
-		case "TALB": // Album
+		case "TALB":
 			metadata.Album = value
-		case "TYER", "TDRC": // Year
+		case "TYER", "TDRC":
 			metadata.Year = value
 			if len(value) >= 4 {
 				metadata.Date = value
 			}
-		case "TCON": // Genre
+		case "TCON":
 			metadata.Genre = cleanGenre(value)
-		case "TRCK": // Track
+		case "TRCK":
 			metadata.TrackNumber = parseTrackNumber(value)
-		case "TPOS": // Disc
+		case "TPOS":
 			metadata.DiscNumber = parseTrackNumber(value)
-		case "TSRC": // ISRC
+		case "TSRC":
 			metadata.ISRC = value
 		}
 
@@ -307,7 +294,6 @@ func parseID3v23Frames(data []byte, metadata *AudioMetadata, version byte, tagUn
 
 // readID3v1 reads ID3v1 tag from end of file
 func readID3v1(file *os.File) (*AudioMetadata, error) {
-	// Seek to last 128 bytes
 	if _, err := file.Seek(-128, io.SeekEnd); err != nil {
 		return nil, err
 	}
@@ -317,7 +303,6 @@ func readID3v1(file *os.File) (*AudioMetadata, error) {
 		return nil, err
 	}
 
-	// Check for "TAG" identifier
 	if string(tag[0:3]) != "TAG" {
 		return nil, fmt.Errorf("no ID3v1 tag")
 	}
@@ -334,7 +319,6 @@ func readID3v1(file *os.File) (*AudioMetadata, error) {
 		metadata.TrackNumber = int(tag[126])
 	}
 
-	// Genre index
 	genreIndex := int(tag[127])
 	if genreIndex < len(id3v1Genres) {
 		metadata.Genre = id3v1Genres[genreIndex]
@@ -372,7 +356,6 @@ func decodeUTF16(data []byte) string {
 		return ""
 	}
 
-	// Check BOM
 	var littleEndian bool
 	if data[0] == 0xFF && data[1] == 0xFE {
 		littleEndian = true
@@ -424,7 +407,6 @@ func cleanGenre(genre string) string {
 		if end > 0 {
 			numStr := genre[1:end]
 			if num, err := strconv.Atoi(numStr); err == nil && num < len(id3v1Genres) {
-				// If there's text after the number, use it
 				if end+1 < len(genre) {
 					return genre[end+1:]
 				}
@@ -513,14 +495,12 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 
 	quality := &MP3Quality{}
 
-	// Get file size for duration estimation
 	stat, err := file.Stat()
 	if err != nil {
 		return nil, err
 	}
 	fileSize := stat.Size()
 
-	// Skip ID3v2 header if present
 	header := make([]byte, 10)
 	if _, err := io.ReadFull(file, header); err != nil {
 		return nil, err
@@ -532,25 +512,20 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 		audioStart = 10 + tagSize
 	}
 
-	// Seek to audio start
 	file.Seek(audioStart, io.SeekStart)
 
-	// Find first valid MP3 frame
 	frameHeader := make([]byte, 4)
 	for i := 0; i < 10000; i++ { // Search first 10KB
 		if _, err := io.ReadFull(file, frameHeader); err != nil {
 			break
 		}
 
-		// Check for sync word (11 set bits)
 		if frameHeader[0] == 0xFF && (frameHeader[1]&0xE0) == 0xE0 {
-			// Parse frame header
 			version := (frameHeader[1] >> 3) & 0x03
 			layer := (frameHeader[1] >> 1) & 0x03
 			bitrateIdx := (frameHeader[2] >> 4) & 0x0F
 			sampleRateIdx := (frameHeader[2] >> 2) & 0x03
 
-			// Get sample rate
 			sampleRates := [][]int{
 				{11025, 12000, 8000},  // MPEG 2.5
 				{0, 0, 0},             // Reserved
@@ -574,7 +549,7 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 
 			// Estimate duration from file size and bitrate
 			if quality.Bitrate > 0 {
-				audioSize := fileSize - audioStart - 128 // Subtract ID3v1 tag
+				audioSize := fileSize - audioStart - 128
 				if audioSize > 0 {
 					quality.Duration = int(audioSize * 8 / int64(quality.Bitrate))
 				}
@@ -583,7 +558,6 @@ func GetMP3Quality(filePath string) (*MP3Quality, error) {
 			break
 		}
 
-		// Seek back 3 bytes to continue search
 		file.Seek(-3, io.SeekCurrent)
 	}
 
@@ -648,13 +622,11 @@ type oggPage struct {
 
 // readOggPageWithHeader reads a single Ogg page including header info
 func readOggPageWithHeader(file *os.File) (*oggPage, error) {
-	// Read page header
 	header := make([]byte, 27)
 	if _, err := io.ReadFull(file, header); err != nil {
 		return nil, err
 	}
 
-	// Check capture pattern "OggS"
 	if string(header[0:4]) != "OggS" {
 		return nil, fmt.Errorf("not an Ogg page")
 	}
@@ -662,19 +634,16 @@ func readOggPageWithHeader(file *os.File) (*oggPage, error) {
 	headerType := header[5]
 	numSegments := int(header[26])
 
-	// Read segment table
 	segmentTable := make([]byte, numSegments)
 	if _, err := io.ReadFull(file, segmentTable); err != nil {
 		return nil, err
 	}
 
-	// Calculate total page size
 	var pageSize int
 	for _, seg := range segmentTable {
 		pageSize += int(seg)
 	}
 
-	// Read page data
 	pageData := make([]byte, pageSize)
 	if _, err := io.ReadFull(file, pageData); err != nil {
 		return nil, err
@@ -734,7 +703,6 @@ func collectOggPackets(file *os.File, maxPackets, maxPages int) ([][]byte, error
 			}
 
 			if len(cur)+segLen > maxPacketSize {
-				// Skip this oversized packet
 				cur = nil
 				skipPacket = true
 				offset += segLen
@@ -796,7 +764,6 @@ func parseVorbisComments(data []byte, metadata *AudioMetadata) {
 		return
 	}
 
-	// Skip vendor string
 	if vendorLen > uint32(len(data)-4) {
 		return
 	}
@@ -805,20 +772,18 @@ func parseVorbisComments(data []byte, metadata *AudioMetadata) {
 		return
 	}
 
-	// Read comment count
 	var commentCount uint32
 	if err := binary.Read(reader, binary.LittleEndian, &commentCount); err != nil {
 		return
 	}
 
-	// Read each comment
 	for i := uint32(0); i < commentCount && i < 100; i++ {
 		var commentLen uint32
 		if err := binary.Read(reader, binary.LittleEndian, &commentLen); err != nil {
 			break
 		}
 
-		if commentLen > 10000 { // Sanity check
+		if commentLen > 10000 {
 			break
 		}
 
@@ -827,7 +792,6 @@ func parseVorbisComments(data []byte, metadata *AudioMetadata) {
 			break
 		}
 
-		// Parse "KEY=VALUE" format
 		parts := strings.SplitN(string(comment), "=", 2)
 		if len(parts) != 2 {
 			continue
@@ -880,7 +844,6 @@ func GetOggQuality(filePath string) (*OggQuality, error) {
 
 	streamType := detectOggStreamType(packets)
 	if streamType == oggStreamUnknown {
-		// Fallback to file extension
 		if strings.HasSuffix(strings.ToLower(filePath), ".opus") {
 			streamType = oggStreamOpus
 		} else {
@@ -910,7 +873,6 @@ func GetOggQuality(filePath string) (*OggQuality, error) {
 		}
 	}
 
-	// Get file size for duration estimation
 	stat, err := file.Stat()
 	if err == nil {
 		// Very rough duration estimate based on file size
@@ -971,7 +933,6 @@ func extractMP3CoverArt(filePath string) ([]byte, string, error) {
 	}
 	defer file.Close()
 
-	// Read ID3v2 header
 	header := make([]byte, 10)
 	if _, err := io.ReadFull(file, header); err != nil {
 		return nil, "", err
@@ -1044,7 +1005,6 @@ func parseAPICFrame(data []byte, version byte) ([]byte, string) {
 	encoding := data[pos]
 	pos++
 
-	// Read MIME type
 	var mimeType string
 	if version == 2 {
 		// ID3v2.2: 3-byte image format (JPG, PNG)
@@ -1075,8 +1035,6 @@ func parseAPICFrame(data []byte, version byte) ([]byte, string) {
 		return nil, ""
 	}
 
-	// Skip picture type
-	// pictureType := data[pos]
 	pos++
 
 	// Skip description (null-terminated, may be UTF-16)
@@ -1085,7 +1043,7 @@ func parseAPICFrame(data []byte, version byte) ([]byte, string) {
 		for pos < len(data) && data[pos] != 0 {
 			pos++
 		}
-		pos++ // Skip null
+		pos++
 	} else {
 		// UTF-16: look for double null
 		for pos+1 < len(data) {
@@ -1101,7 +1059,6 @@ func parseAPICFrame(data []byte, version byte) ([]byte, string) {
 		return nil, ""
 	}
 
-	// Rest is image data
 	return data[pos:], mimeType
 }
 
@@ -1157,7 +1114,6 @@ func extractPictureFromVorbisComments(data []byte) ([]byte, string) {
 
 	reader := bytes.NewReader(data)
 
-	// Skip vendor string
 	var vendorLen uint32
 	if err := binary.Read(reader, binary.LittleEndian, &vendorLen); err != nil {
 		return nil, ""
@@ -1167,7 +1123,6 @@ func extractPictureFromVorbisComments(data []byte) ([]byte, string) {
 	}
 	reader.Seek(int64(vendorLen), io.SeekCurrent)
 
-	// Read comment count
 	var commentCount uint32
 	if err := binary.Read(reader, binary.LittleEndian, &commentCount); err != nil {
 		return nil, ""
@@ -1188,7 +1143,6 @@ func extractPictureFromVorbisComments(data []byte) ([]byte, string) {
 			break
 		}
 
-		// Check for METADATA_BLOCK_PICTURE=
 		key := "METADATA_BLOCK_PICTURE="
 		if len(comment) > len(key) && strings.ToUpper(string(comment[:len(key)])) == key {
 			// Base64-encoded FLAC picture block
@@ -1200,7 +1154,6 @@ func extractPictureFromVorbisComments(data []byte) ([]byte, string) {
 			}
 			decoded = decoded[:n]
 
-			// Parse FLAC picture block
 			imageData, mimeType := parseFLACPictureBlock(decoded)
 			if len(imageData) > 0 {
 				return imageData, mimeType
@@ -1219,43 +1172,35 @@ func parseFLACPictureBlock(data []byte) ([]byte, string) {
 
 	reader := bytes.NewReader(data)
 
-	// Picture type (4 bytes)
 	var pictureType uint32
 	binary.Read(reader, binary.BigEndian, &pictureType)
 
-	// MIME type length (4 bytes)
 	var mimeLen uint32
 	binary.Read(reader, binary.BigEndian, &mimeLen)
 	if mimeLen > 256 {
 		return nil, ""
 	}
 
-	// MIME type
 	mimeBytes := make([]byte, mimeLen)
 	reader.Read(mimeBytes)
 	mimeType := string(mimeBytes)
 
-	// Description length (4 bytes)
 	var descLen uint32
 	binary.Read(reader, binary.BigEndian, &descLen)
 	if descLen > 10000 {
 		return nil, ""
 	}
 
-	// Skip description
 	reader.Seek(int64(descLen), io.SeekCurrent)
 
-	// Skip width, height, color depth, colors used (16 bytes)
 	reader.Seek(16, io.SeekCurrent)
 
-	// Image data length (4 bytes)
 	var dataLen uint32
 	binary.Read(reader, binary.BigEndian, &dataLen)
 	if dataLen > 10000000 { // 10MB
 		return nil, ""
 	}
 
-	// Image data
 	imageData := make([]byte, dataLen)
 	reader.Read(imageData)
 
@@ -1281,7 +1226,6 @@ func base64StdDecode(dst, src []byte) (int, error) {
 
 	si, di := 0, 0
 	for si < len(src) {
-		// Skip whitespace and newlines
 		for si < len(src) && (src[si] == '\n' || src[si] == '\r' || src[si] == ' ' || src[si] == '\t') {
 			si++
 		}
@@ -1289,7 +1233,6 @@ func base64StdDecode(dst, src []byte) (int, error) {
 			break
 		}
 
-		// Read 4 characters
 		var vals [4]byte
 		var valCount int
 		for valCount < 4 && si < len(src) {
@@ -1310,7 +1253,6 @@ func base64StdDecode(dst, src []byte) (int, error) {
 			break
 		}
 
-		// Decode
 		if di < len(dst) {
 			dst[di] = vals[0]<<2 | vals[1]>>4
 			di++
@@ -1334,7 +1276,6 @@ func extractAnyCoverArt(filePath string) ([]byte, string, error) {
 
 	switch ext {
 	case ".flac":
-		// Use existing ExtractCoverArt function
 		data, err := ExtractCoverArt(filePath)
 		if err != nil {
 			return nil, "", err
@@ -1372,7 +1313,6 @@ func SaveCoverToCache(filePath, cacheDir string) (string, error) {
 	}
 	hash := hashString(cacheKey)
 
-	// Check if cover already cached
 	jpgPath := filepath.Join(cacheDir, fmt.Sprintf("cover_%x.jpg", hash))
 	pngPath := filepath.Join(cacheDir, fmt.Sprintf("cover_%x.png", hash))
 
@@ -1383,18 +1323,15 @@ func SaveCoverToCache(filePath, cacheDir string) (string, error) {
 		return pngPath, nil
 	}
 
-	// Extract cover art
 	imageData, mimeType, err := extractAnyCoverArt(filePath)
 	if err != nil {
 		return "", err
 	}
 
-	// Ensure cache directory exists
 	if err := os.MkdirAll(cacheDir, 0755); err != nil {
 		return "", fmt.Errorf("failed to create cache dir: %w", err)
 	}
 
-	// Determine file extension
 	var cachePath string
 	if strings.Contains(mimeType, "png") {
 		cachePath = pngPath
@@ -1402,7 +1339,6 @@ func SaveCoverToCache(filePath, cacheDir string) (string, error) {
 		cachePath = jpgPath
 	}
 
-	// Write to file
 	if err := os.WriteFile(cachePath, imageData, 0644); err != nil {
 		return "", fmt.Errorf("failed to write cover: %w", err)
 	}

go_backend/exports.go

@@ -194,7 +194,6 @@ func DownloadTrack(requestJSON string) (string, error) {
 		return errorResponse("Invalid request: " + err.Error())
 	}
 
-	// Trim whitespace from string fields to prevent filename/path issues
 	req.TrackName = strings.TrimSpace(req.TrackName)
 	req.ArtistName = strings.TrimSpace(req.ArtistName)
 	req.AlbumName = strings.TrimSpace(req.AlbumName)
@@ -1447,8 +1446,8 @@ func CustomSearchWithExtensionJSON(extensionID, query string, optionsJSON string
 			"disc_number":  track.DiscNumber,
 			"isrc":         track.ISRC,
 			"provider_id":  track.ProviderID,
-			"item_type":    track.ItemType,  // track, album, or playlist
-			"album_type":   track.AlbumType, // album, single, ep, compilation
+			"item_type":    track.ItemType,
+			"album_type":   track.AlbumType,
 		}
 	}
 
@@ -1544,7 +1543,6 @@ func HandleURLWithExtensionJSON(url string) (string, error) {
 		response["tracks"] = tracks
 	}
 
-	// Add album info if present
 	if result.Album != nil {
 		response["album"] = map[string]interface{}{
 			"id":           result.Album.ID,
@@ -1662,7 +1660,6 @@ func GetAlbumWithExtensionJSON(extensionID, albumID string) (string, error) {
 		if trackCover == "" {
 			trackCover = album.CoverURL
 		}
-		// Use track number from extension, fallback to index+1 if not provided
 		trackNum := track.TrackNumber
 		if trackNum == 0 {
 			trackNum = i + 1
@@ -1840,7 +1837,6 @@ func GetArtistWithExtensionJSON(extensionID, artistID string) (string, error) {
 		"provider_id": artist.ProviderID,
 	}
 
-	// Add header image if present
 	if artist.HeaderImage != "" {
 		response["header_image"] = artist.HeaderImage
 	}
@@ -1849,7 +1845,6 @@ func GetArtistWithExtensionJSON(extensionID, artistID string) (string, error) {
 		response["listeners"] = artist.Listeners
 	}
 
-	// Add top tracks if present
 	if len(artist.TopTracks) > 0 {
 		topTracks := make([]map[string]interface{}, len(artist.TopTracks))
 		for i, track := range artist.TopTracks {

go_backend/extension_providers.go

@@ -31,8 +31,8 @@ type ExtTrackMetadata struct {
 	DiscNumber  int    `json:"disc_number,omitempty"`
 	ISRC        string `json:"isrc,omitempty"`
 	ProviderID  string `json:"provider_id"`
-	ItemType    string `json:"item_type,omitempty"`  // track, album, or playlist - for extension search results
-	AlbumType   string `json:"album_type,omitempty"` // album, single, ep, compilation
+	ItemType    string `json:"item_type,omitempty"`
+	AlbumType   string `json:"album_type,omitempty"`
 	// Enrichment fields from Odesli/song.link
 	TidalID       string            `json:"tidal_id,omitempty"`
 	QobuzID       string            `json:"qobuz_id,omitempty"`
@@ -176,7 +176,6 @@ func (p *ExtensionProviderWrapper) SearchTracks(query string, limit int) (*ExtSe
 		return nil, fmt.Errorf("searchTracks returned null")
 	}
 
-	// Convert result to Go struct
 	exported := result.Export()
 	jsonBytes, err := json.Marshal(exported)
 	if err != nil {
@@ -379,7 +378,7 @@ func (p *ExtensionProviderWrapper) EnrichTrack(track *ExtTrackMetadata) (*ExtTra
 	trackJSON, err := json.Marshal(track)
 	if err != nil {
 		GoLog("[Extension] EnrichTrack: failed to marshal track: %v\n", err)
-		return track, nil // Return original on error
+		return track, nil
 	}
 
 	script := fmt.Sprintf(`
@@ -399,7 +398,7 @@ func (p *ExtensionProviderWrapper) EnrichTrack(track *ExtTrackMetadata) (*ExtTra
 		} else {
 			GoLog("[Extension] EnrichTrack error for %s: %v\n", p.extension.ID, err)
 		}
-		return track, nil // Return original on error
+		return track, nil
 	}
 
 	// If extension doesn't implement enrichTrack or returns null, return original
@@ -843,14 +842,12 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 			provider := NewExtensionProviderWrapper(ext)
 
 			// For tracks from extension search, use the track ID directly (e.g., "youtube:VIDEO_ID")
-			// The extension already knows how to handle this ID
-			trackID := req.SpotifyID // This contains the extension's track ID (e.g., "youtube:xxx")
+			trackID := req.SpotifyID
 
 			GoLog("[DownloadWithExtensionFallback] Downloading from source extension with trackID: %s (skipBuiltInFallback: %v)\n", trackID, skipBuiltIn)
 
 			outputPath := buildOutputPath(req)
 
-			// Download directly using the track ID from the extension
 			result, err := provider.Download(trackID, req.Quality, outputPath, func(percent int) {
 				if req.ItemID != "" {
 					SetItemProgress(req.ItemID, float64(percent), 0, 0)
@@ -879,7 +876,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 					}
 				}
 
-				// If extension has skipMetadataEnrichment, copy metadata
 				if ext.Manifest.SkipMetadataEnrichment {
 					resp.SkipMetadataEnrichment = true
 					if result.Title != "" {
@@ -946,12 +942,10 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 
 	// Continue with priority list
 	for _, providerID := range priority {
-		// Skip if we already tried this as source
 		if providerID == req.Source {
 			continue
 		}
 
-		// Skip built-in providers if skipBuiltIn is set
 		if skipBuiltIn && isBuiltInProvider(providerID) {
 			GoLog("[DownloadWithExtensionFallback] Skipping built-in provider %s (skipBuiltInFallback)\n", providerID)
 			continue
@@ -1065,7 +1059,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 					}
 				}
 
-				// If extension has skipMetadataEnrichment and returned metadata, use it
 				if ext.Manifest.SkipMetadataEnrichment {
 					resp.SkipMetadataEnrichment = true
 					// Copy metadata from extension result if provided
@@ -1276,7 +1269,6 @@ func (p *ExtensionProviderWrapper) CustomSearch(query string, options map[string
 	}
 
 	if result == nil || goja.IsUndefined(result) || goja.IsNull(result) {
-		// Return empty array instead of error for no results
 		return []ExtTrackMetadata{}, nil
 	}
 
@@ -1291,7 +1283,6 @@ func (p *ExtensionProviderWrapper) CustomSearch(query string, options map[string
 		return nil, fmt.Errorf("failed to parse search result: %w", err)
 	}
 
-	// Return empty array if no tracks found
 	if tracks == nil {
 		tracks = []ExtTrackMetadata{}
 	}
@@ -1362,7 +1353,6 @@ func (p *ExtensionProviderWrapper) HandleURL(url string) (*ExtURLHandleResult, e
 		return nil, fmt.Errorf("failed to parse URL handle result: %w", err)
 	}
 
-	// Set provider ID on tracks
 	if handleResult.Track != nil {
 		handleResult.Track.ProviderID = p.extension.ID
 	}

go_backend/library_scan.go

@@ -46,7 +46,7 @@ var (
 	libraryScanProgressMu sync.RWMutex
 	libraryScanCancel     chan struct{}
 	libraryScanCancelMu   sync.Mutex
-	libraryCoverCacheDir  string // Directory to cache extracted cover art
+	libraryCoverCacheDir  string
 	libraryCoverCacheMu   sync.RWMutex
 )
 
@@ -73,7 +73,6 @@ func ScanLibraryFolder(folderPath string) (string, error) {
 		return "[]", fmt.Errorf("folder path is empty")
 	}
 
-	// Check if folder exists
 	info, err := os.Stat(folderPath)
 	if err != nil {
 		return "[]", fmt.Errorf("folder not found: %w", err)
@@ -82,12 +81,10 @@ func ScanLibraryFolder(folderPath string) (string, error) {
 		return "[]", fmt.Errorf("path is not a folder: %s", folderPath)
 	}
 
-	// Reset progress
 	libraryScanProgressMu.Lock()
 	libraryScanProgress = LibraryScanProgress{}
 	libraryScanProgressMu.Unlock()
 
-	// Create cancel channel
 	libraryScanCancelMu.Lock()
 	if libraryScanCancel != nil {
 		close(libraryScanCancel)
@@ -96,11 +93,10 @@ func ScanLibraryFolder(folderPath string) (string, error) {
 	cancelCh := libraryScanCancel
 	libraryScanCancelMu.Unlock()
 
-	// First pass: count audio files
 	var audioFiles []string
 	err = filepath.Walk(folderPath, func(path string, info os.FileInfo, err error) error {
 		if err != nil {
-			return nil // Skip errors, continue walking
+			return nil
 		}
 
 		select {
@@ -136,7 +132,6 @@ func ScanLibraryFolder(folderPath string) (string, error) {
 
 	GoLog("[LibraryScan] Found %d audio files to scan\n", totalFiles)
 
-	// Second pass: read metadata from each file
 	results := make([]LibraryScanResult, 0, totalFiles)
 	scanTime := time.Now().UTC().Format(time.RFC3339)
 	errorCount := 0
@@ -148,14 +143,12 @@ func ScanLibraryFolder(folderPath string) (string, error) {
 		default:
 		}
 
-		// Update progress
 		libraryScanProgressMu.Lock()
 		libraryScanProgress.ScannedFiles = i + 1
 		libraryScanProgress.CurrentFile = filepath.Base(filePath)
 		libraryScanProgress.ProgressPct = float64(i+1) / float64(totalFiles) * 100
 		libraryScanProgressMu.Unlock()
 
-		// Read metadata
 		result, err := scanAudioFile(filePath, scanTime)
 		if err != nil {
 			errorCount++
@@ -166,7 +159,6 @@ func ScanLibraryFolder(folderPath string) (string, error) {
 		results = append(results, *result)
 	}
 
-	// Mark complete
 	libraryScanProgressMu.Lock()
 	libraryScanProgress.ErrorCount = errorCount
 	libraryScanProgress.IsComplete = true
@@ -193,7 +185,6 @@ func scanAudioFile(filePath, scanTime string) (*LibraryScanResult, error) {
 		Format:    strings.TrimPrefix(ext, "."),
 	}
 
-	// Try to extract and cache cover art
 	libraryCoverCacheMu.RLock()
 	coverCacheDir := libraryCoverCacheDir
 	libraryCoverCacheMu.RUnlock()
@@ -204,7 +195,6 @@ func scanAudioFile(filePath, scanTime string) (*LibraryScanResult, error) {
 		}
 	}
 
-	// Try to read metadata based on format
 	switch ext {
 	case ".flac":
 		return scanFLACFile(filePath, result)
@@ -213,10 +203,8 @@ func scanAudioFile(filePath, scanTime string) (*LibraryScanResult, error) {
 	case ".mp3":
 		return scanMP3File(filePath, result)
 	case ".opus", ".ogg":
-		// Opus files often use same container as Ogg Vorbis
 		return scanOggFile(filePath, result)
 	default:
-		// Fallback: use filename as title
 		return scanFromFilename(filePath, result)
 	}
 }
@@ -225,7 +213,6 @@ func scanAudioFile(filePath, scanTime string) (*LibraryScanResult, error) {
 func scanFLACFile(filePath string, result *LibraryScanResult) (*LibraryScanResult, error) {
 	metadata, err := ReadMetadata(filePath)
 	if err != nil {
-		// Fallback to filename
 		return scanFromFilename(filePath, result)
 	}
 
@@ -239,7 +226,6 @@ func scanFLACFile(filePath string, result *LibraryScanResult) (*LibraryScanResul
 	result.ReleaseDate = metadata.Date
 	result.Genre = metadata.Genre
 
-	// Read audio quality
 	quality, err := GetAudioQuality(filePath)
 	if err == nil {
 		result.BitDepth = quality.BitDepth
@@ -249,7 +235,6 @@ func scanFLACFile(filePath string, result *LibraryScanResult) (*LibraryScanResul
 		}
 	}
 
-	// Ensure we have at least a title
 	if result.TrackName == "" {
 		result.TrackName = strings.TrimSuffix(filepath.Base(filePath), filepath.Ext(filePath))
 	}
@@ -265,14 +250,12 @@ func scanFLACFile(filePath string, result *LibraryScanResult) (*LibraryScanResul
 
 // scanM4AFile reads metadata from M4A/AAC file
 func scanM4AFile(filePath string, result *LibraryScanResult) (*LibraryScanResult, error) {
-	// M4A metadata reading is limited, try audio quality at least
 	quality, err := GetM4AQuality(filePath)
 	if err == nil {
 		result.BitDepth = quality.BitDepth
 		result.SampleRate = quality.SampleRate
 	}
 
-	// Fallback to filename parsing
 	return scanFromFilename(filePath, result)
 }
 
@@ -298,7 +281,6 @@ func scanMP3File(filePath string, result *LibraryScanResult) (*LibraryScanResult
 	}
 	result.ISRC = metadata.ISRC
 
-	// Get audio quality info
 	quality, err := GetMP3Quality(filePath)
 	if err == nil {
 		result.SampleRate = quality.SampleRate
@@ -306,7 +288,6 @@ func scanMP3File(filePath string, result *LibraryScanResult) (*LibraryScanResult
 		result.Duration = quality.Duration
 	}
 
-	// Ensure we have at least a title
 	if result.TrackName == "" {
 		result.TrackName = strings.TrimSuffix(filepath.Base(filePath), filepath.Ext(filePath))
 	}
@@ -338,7 +319,6 @@ func scanOggFile(filePath string, result *LibraryScanResult) (*LibraryScanResult
 	result.Genre = metadata.Genre
 	result.ReleaseDate = metadata.Date
 
-	// Get audio quality info
 	quality, err := GetOggQuality(filePath)
 	if err == nil {
 		result.SampleRate = quality.SampleRate
@@ -346,7 +326,6 @@ func scanOggFile(filePath string, result *LibraryScanResult) (*LibraryScanResult
 		result.Duration = quality.Duration
 	}
 
-	// Ensure we have at least a title
 	if result.TrackName == "" {
 		result.TrackName = strings.TrimSuffix(filepath.Base(filePath), filepath.Ext(filePath))
 	}
@@ -364,16 +343,8 @@ func scanOggFile(filePath string, result *LibraryScanResult) (*LibraryScanResult
 func scanFromFilename(filePath string, result *LibraryScanResult) (*LibraryScanResult, error) {
 	filename := strings.TrimSuffix(filepath.Base(filePath), filepath.Ext(filePath))
 
-	// Common patterns:
-	// "Artist - Title"
-	// "01 - Title"
-	// "01. Title"
-	// "Title"
-
-	// Try "Artist - Title" pattern
 	parts := strings.SplitN(filename, " - ", 2)
 	if len(parts) == 2 {
-		// Check if first part looks like a track number
 		if len(parts[0]) <= 3 && isNumeric(parts[0]) {
 			result.TrackName = parts[1]
 			result.ArtistName = "Unknown Artist"
@@ -382,9 +353,7 @@ func scanFromFilename(filePath string, result *LibraryScanResult) (*LibraryScanR
 			result.TrackName = parts[1]
 		}
 	} else {
-		// Try "01. Title" or "01 Title" pattern
 		if len(filename) > 3 && isNumeric(filename[:2]) {
-			// Skip track number
 			title := strings.TrimLeft(filename[2:], " .-")
 			result.TrackName = title
 		} else {
@@ -393,7 +362,6 @@ func scanFromFilename(filePath string, result *LibraryScanResult) (*LibraryScanR
 		result.ArtistName = "Unknown Artist"
 	}
 
-	// Use parent folder as album name
 	dir := filepath.Dir(filePath)
 	result.AlbumName = filepath.Base(dir)
 	if result.AlbumName == "." || result.AlbumName == "" {
@@ -415,7 +383,6 @@ func isNumeric(s string) bool {
 
 // generateLibraryID creates a unique ID for a library item
 func generateLibraryID(filePath string) string {
-	// Use file path hash as ID
 	return fmt.Sprintf("lib_%x", hashString(filePath))
 }
 

go_backend/spotify.go

@@ -63,7 +63,6 @@ var (
 	credentialsMu      sync.RWMutex
 )
 
-// ErrNoSpotifyCredentials is returned when Spotify credentials are not configured
 var ErrNoSpotifyCredentials = errors.New("Spotify credentials not configured. Please set your own Client ID and Secret in Settings, or use Deezer as metadata source (free, no credentials required)")
 
 func SetSpotifyCredentials(clientID, clientSecret string) {
@@ -141,7 +140,7 @@ type TrackMetadata struct {
 	DiscNumber  int    `json:"disc_number,omitempty"`
 	ExternalURL string `json:"external_urls"`
 	ISRC        string `json:"isrc"`
-	AlbumType   string `json:"album_type,omitempty"` // album, single, ep, compilation
+	AlbumType   string `json:"album_type,omitempty"`
 }
 
 type AlbumTrackMetadata struct {
@@ -210,7 +209,7 @@ type ArtistAlbumMetadata struct {
 	ReleaseDate string `json:"release_date"`
 	TotalTracks int    `json:"total_tracks"`
 	Images      string `json:"images"`
-	AlbumType   string `json:"album_type"` // album, single, compilation
+	AlbumType   string `json:"album_type"`
 	Artists     string `json:"artists"`
 }
 
@@ -532,7 +531,6 @@ func (c *SpotifyMetadataClient) fetchAlbum(ctx context.Context, albumID, token s
 
 	albumImage := firstImageURL(data.Images)
 
-	// Get first artist ID
 	var firstArtistId string
 	if len(data.Artists) > 0 {
 		firstArtistId = data.Artists[0].ID
@@ -565,7 +563,6 @@ func (c *SpotifyMetadataClient) fetchAlbum(ctx context.Context, albumID, token s
 
 	fmt.Printf("[Spotify] Album has %d tracks (total: %d)\n", len(allTrackItems), data.TotalTracks)
 
-	// Collect track IDs for parallel ISRC fetching
 	trackIDs := make([]string, len(allTrackItems))
 	for i, item := range allTrackItems {
 		trackIDs[i] = item.ID

lib/providers/download_queue_provider.dart

@@ -1034,14 +1034,12 @@ void removeItem(String id) {
     }
 
     try {
-      // Get base download directory
       String baseDir = state.outputDir;
       if (baseDir.isEmpty) {
         final dir = await getApplicationDocumentsDirectory();
         baseDir = dir.path;
       }
 
-      // Create failed_downloads subfolder
       final failedDownloadsDir = '$baseDir/failed_downloads';
       final failedDir = Directory(failedDownloadsDir);
       if (!await failedDir.exists()) {
@@ -1057,11 +1055,9 @@ void removeItem(String id) {
       final file = File(filePath);
       final bool fileExists = await file.exists();
 
-      // Build content for new entries
       final buffer = StringBuffer();
       
       if (!fileExists) {
-        // New file - add header
         buffer.writeln('# SpotiFLAC Failed Downloads');
         buffer.writeln('# Date: $dateStr');
         buffer.writeln('#');
@@ -1069,7 +1065,6 @@ void removeItem(String id) {
         buffer.writeln('');
       }
 
-      // Add timestamp for this batch
       final timeStr = '${now.hour.toString().padLeft(2, '0')}:${now.minute.toString().padLeft(2, '0')}:${now.second.toString().padLeft(2, '0')}';
       
       for (final item in failedItems) {
@@ -1081,7 +1076,6 @@ void removeItem(String id) {
         buffer.writeln('[$timeStr] ${track.name} - ${track.artistName} | $spotifyUrl | $error');
       }
 
-      // Append or create file
       if (fileExists) {
         await file.writeAsString(buffer.toString(), mode: FileMode.append);
         _log.i('Appended ${failedItems.length} failed downloads to: $filePath');
@@ -1553,7 +1547,6 @@ void removeItem(String id) {
 
       _log.d('Opus Metadata map content: $metadata');
 
-      // Handle lyrics based on lyricsMode setting
       final lyricsMode = settings.lyricsMode;
       final shouldEmbed = lyricsMode == 'embed' || lyricsMode == 'both';
       final shouldSaveExternal = lyricsMode == 'external' || lyricsMode == 'both';
@@ -1571,13 +1564,11 @@ void removeItem(String id) {
           );
 
           if (lrcContent.isNotEmpty) {
-            // Embed lyrics in file metadata if mode is 'embed' or 'both'
             if (shouldEmbed) {
               metadata['LYRICS'] = lrcContent;
               _log.d('Lyrics fetched for Opus embedding (${lrcContent.length} chars)');
             }
             
-            // Save external LRC file if mode is 'external' or 'both'
             if (shouldSaveExternal) {
               try {
                 final lrcPath = opusPath.replaceAll(RegExp(r'\.opus$', caseSensitive: false), '.lrc');
@@ -2137,7 +2128,6 @@ result = await PlatformBridge.downloadWithExtensions(
                 progress: 0.95,
               );
               
-              // Convert M4A to the selected format
               final format = tidalHighFormat.startsWith('opus') ? 'opus' : 'mp3';
               final convertedPath = await FFmpegService.convertM4aToLossy(
                 filePath,
@@ -2154,7 +2144,6 @@ result = await PlatformBridge.downloadWithExtensions(
                 actualQuality = '${format.toUpperCase()} $bitrateDisplay';
                 _log.i('Successfully converted M4A to $format: $convertedPath');
                 
-                // Embed metadata
                 _log.i('Embedding metadata to $format...');
                 updateItemStatus(
                   item.id,
@@ -2333,13 +2322,11 @@ result = await PlatformBridge.downloadWithExtensions(
 
         _completedInSession++;
         
-        // Check if this track is already in download history
         final historyNotifier = ref.read(downloadHistoryProvider.notifier);
         final existingInHistory = historyNotifier.getBySpotifyId(trackToDownload.id) ??
             (trackToDownload.isrc != null ? historyNotifier.getByIsrc(trackToDownload.isrc!) : null);
         
         if (wasExisting && existingInHistory != null) {
-          // File exists and is already in download history - skip adding
           _log.i('Track already in library, skipping history update');
           await _notificationService.showDownloadComplete(
             trackName: item.track.name,

lib/providers/local_library_provider.dart

@@ -10,7 +10,6 @@ final _log = AppLogger('LocalLibrary');
 
 const _lastScannedAtKey = 'local_library_last_scanned_at';
 
-/// State for local library
 class LocalLibraryState {
   final List<LocalLibraryItem> items;
   final bool isScanning;
@@ -92,7 +91,6 @@ class LocalLibraryState {
   }
 }
 
-/// Provider for local library state management
 class LocalLibraryNotifier extends Notifier<LocalLibraryState> {
   final LibraryDatabase _db = LibraryDatabase.instance;
   Timer? _progressTimer;
@@ -120,7 +118,6 @@ class LocalLibraryNotifier extends Notifier<LocalLibraryState> {
           .map((e) => LocalLibraryItem.fromJson(e))
           .toList();
       
-      // Load lastScannedAt from SharedPreferences
       DateTime? lastScannedAt;
       try {
         final prefs = await SharedPreferences.getInstance();
@@ -161,7 +158,6 @@ class LocalLibraryNotifier extends Notifier<LocalLibraryState> {
       scanErrorCount: 0,
     );
 
-    // Set cover cache directory before scanning
     try {
       final cacheDir = await getApplicationCacheDirectory();
       final coverCacheDir = '${cacheDir.path}/library_covers';
@@ -171,23 +167,19 @@ class LocalLibraryNotifier extends Notifier<LocalLibraryState> {
       _log.w('Failed to set cover cache directory: $e');
     }
 
-    // Start progress polling
     _startProgressPolling();
 
     try {
       final results = await PlatformBridge.scanLibraryFolder(folderPath);
       
-      // Convert results to LocalLibraryItem and save to database
       final items = <LocalLibraryItem>[];
       for (final json in results) {
         final item = LocalLibraryItem.fromJson(json);
         items.add(item);
       }
 
-      // Batch insert into database
       await _db.upsertBatch(items.map((e) => e.toJson()).toList());
 
-      // Save lastScannedAt to SharedPreferences
       final now = DateTime.now();
       try {
         final prefs = await SharedPreferences.getInstance();
@@ -197,7 +189,6 @@ class LocalLibraryNotifier extends Notifier<LocalLibraryState> {
         _log.w('Failed to save lastScannedAt: $e');
       }
 
-      // Update state
       state = state.copyWith(
         items: items,
         isScanning: false,
@@ -262,7 +253,6 @@ class LocalLibraryNotifier extends Notifier<LocalLibraryState> {
   Future<void> clearLibrary() async {
     await _db.clearAll();
     
-    // Clear lastScannedAt from SharedPreferences
     try {
       final prefs = await SharedPreferences.getInstance();
       await prefs.remove(_lastScannedAtKey);

lib/providers/settings_provider.dart

@@ -292,7 +292,6 @@ void setUseAllFilesAccess(bool enabled) {
     _saveSettings();
   }
 
-  // Local Library Settings
   void setLocalLibraryEnabled(bool enabled) {
     state = state.copyWith(localLibraryEnabled: enabled);
     _saveSettings();

lib/screens/album_screen.dart

@@ -695,7 +695,6 @@ child: ListTile(
   void _handleTap(BuildContext context, WidgetRef ref, {required bool isQueued, required bool isInHistory, required bool isInLocalLibrary}) async {
     if (isQueued) return;
     
-    // Check if track already exists in local library
     if (isInLocalLibrary) {
       if (context.mounted) {
         ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(context.l10n.snackbarAlreadyInLibrary(track.name))));

lib/screens/artist_screen.dart

@@ -103,7 +103,6 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
   bool _showTitleInAppBar = false;
   final ScrollController _scrollController = ScrollController();
 
-  // Selection mode state
   bool _isSelectionMode = false;
   final Set<String> _selectedAlbumIds = {};
   bool _isFetchingDiscography = false;
@@ -112,7 +111,6 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
   void initState() {
     super.initState();
     
-    // Setup scroll listener for sticky title
     _scrollController.addListener(_onScroll);
     
     WidgetsBinding.instance.addPostFrameCallback((_) {
@@ -322,11 +320,9 @@ return PopScope(
             if (compilations.isNotEmpty) 
               SliverToBoxAdapter(child: _buildAlbumSection(context.l10n.artistCompilations, compilations, colorScheme)),
           ],
-          // Add padding at bottom for selection bar
           SliverToBoxAdapter(child: SizedBox(height: _isSelectionMode ? 120 : 32)),
         ],
       ),
-          // Selection action bar
           if (_isSelectionMode)
             _buildSelectionBar(context, colorScheme, albums),
         ],
@@ -404,14 +400,12 @@ return PopScope(
             padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
             child: Row(
               children: [
-                // Close button
                 IconButton(
                   onPressed: _exitSelectionMode,
                   icon: const Icon(Icons.close),
                   tooltip: context.l10n.dialogCancel,
                 ),
                 const SizedBox(width: 8),
-                // Selection info
                 Expanded(
                   child: Column(
                     crossAxisAlignment: CrossAxisAlignment.start,
@@ -433,13 +427,11 @@ return PopScope(
                     ],
                   ),
                 ),
-                // Select all / Deselect button
                 TextButton(
                   onPressed: allSelected ? _deselectAll : () => _selectAll(allAlbums),
                   child: Text(allSelected ? context.l10n.actionDeselect : context.l10n.actionSelectAll),
                 ),
                 const SizedBox(width: 8),
-                // Download button
                 FilledButton.icon(
                   onPressed: selectedCount > 0 ? () => _downloadSelectedAlbums(context, selectedAlbums) : null,
                   icon: const Icon(Icons.download, size: 18),
@@ -473,7 +465,6 @@ return PopScope(
           child: Column(
             mainAxisSize: MainAxisSize.min,
             children: [
-              // Handle bar
               Container(
                 width: 40,
                 height: 4,
@@ -483,7 +474,6 @@ return PopScope(
                   borderRadius: BorderRadius.circular(2),
                 ),
               ),
-              // Title
               Padding(
                 padding: const EdgeInsets.fromLTRB(24, 0, 24, 16),
                 child: Row(
@@ -577,7 +567,6 @@ return PopScope(
     
     setState(() => _isFetchingDiscography = true);
 
-    // Show progress dialog
     if (!mounted) {
       setState(() => _isFetchingDiscography = false);
       return;
@@ -599,7 +588,6 @@ return PopScope(
     int fetchedCount = 0;
     int failedCount = 0;
 
-    // Fetch tracks from each album
     for (final album in albums) {
       if (!_isFetchingDiscography) break; // Cancelled
 
@@ -620,12 +608,10 @@ return PopScope(
 
     setState(() => _isFetchingDiscography = false);
 
-    // Close progress dialog
     if (mounted) {
       Navigator.of(context, rootNavigator: true).pop();
     }
 
-    // Show warning if some albums failed
     if (failedCount > 0 && mounted) {
       ScaffoldMessenger.of(context).showSnackBar(
         SnackBar(content: Text(context.l10n.discographyFailedToFetch)),
@@ -668,14 +654,12 @@ return PopScope(
       return;
     }
 
-    // Add to queue
     ref.read(downloadQueueProvider.notifier).addMultipleToQueue(
       tracksToQueue,
       service,
       qualityOverride: qualityOverride,
     );
 
-    // Show success message
     if (mounted) {
       final message = skippedCount > 0
           ? context.l10n.discographySkippedDownloaded(tracksToQueue.length, skippedCount)
@@ -698,14 +682,12 @@ return PopScope(
 
   Future<List<Track>> _fetchAlbumTracks(ArtistAlbum album) async {
     if (album.providerId != null && album.providerId!.isNotEmpty) {
-      // Extension album
       final result = await PlatformBridge.getAlbumWithExtension(album.providerId!, album.id);
       if (result != null && result['tracks'] != null) {
         final tracksList = result['tracks'] as List<dynamic>;
         return tracksList.map((t) => _parseTrack(t as Map<String, dynamic>)).toList();
       }
     } else if (album.id.startsWith('deezer:')) {
-      // Deezer album
       final deezerId = album.id.replaceFirst('deezer:', '');
       final metadata = await PlatformBridge.getDeezerMetadata('album', deezerId);
       if (metadata['tracks'] != null) {
@@ -713,7 +695,6 @@ return PopScope(
         return tracksList.map((t) => _parseTrackFromDeezer(t as Map<String, dynamic>, album)).toList();
       }
     } else {
-      // Spotify album
       final url = 'https://open.spotify.com/album/${album.id}';
       final result = await PlatformBridge.handleURLWithExtension(url);
       if (result != null && result['tracks'] != null) {
@@ -1068,7 +1049,6 @@ if (hasValidImage)
   void _handlePopularTrackTap(Track track, {required bool isQueued, required bool isInHistory, required bool isInLocalLibrary}) async {
     if (isQueued) return;
     
-    // Check if track already exists in local library
     if (isInLocalLibrary) {
       if (mounted) {
         ScaffoldMessenger.of(context).showSnackBar(

lib/screens/home_tab.dart

@@ -513,7 +513,6 @@ class _HomeTabState extends ConsumerState<HomeTab> with AutomaticKeepAliveClient
     Extension? currentSearchExtension;
     List<SearchFilter> searchFilters = [];
     
-    // Check if using extension search provider
     final isUsingExtensionSearch = currentSearchProvider != null && 
         currentSearchProvider.isNotEmpty &&
         extState.extensions.any((e) => e.id == currentSearchProvider && e.enabled);
@@ -2567,7 +2566,6 @@ class _TrackItemWithStatus extends ConsumerWidget {
   void _handleTap(BuildContext context, WidgetRef ref, {required bool isQueued, required bool isInHistory, required bool isInLocalLibrary}) async {
     if (isQueued) return;
     
-    // Check if track already exists in local library
     if (isInLocalLibrary) {
       if (context.mounted) {
         ScaffoldMessenger.of(context).showSnackBar(

lib/screens/playlist_screen.dart

@@ -502,7 +502,6 @@ leading: track.coverUrl != null
   void _handleTap(BuildContext context, WidgetRef ref, {required bool isQueued, required bool isInHistory, required bool isInLocalLibrary}) async {
     if (isQueued) return;
     
-    // Check if track already exists in local library
     if (isInLocalLibrary) {
       if (context.mounted) {
         ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(context.l10n.snackbarAlreadyInLibrary(track.name))));

lib/screens/queue_tab.dart

@@ -28,13 +28,12 @@ class UnifiedLibraryItem {
   final String artistName;
   final String albumName;
   final String? coverUrl;
-  final String? localCoverPath; // For local library items with extracted cover
+  final String? localCoverPath;
   final String filePath;
   final String? quality;
   final DateTime addedAt;
   final LibraryItemSource source;
   
-  // Original items for navigation
   final DownloadHistoryItem? historyItem;
   final LocalLibraryItem? localItem;
 
@@ -258,7 +257,6 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     'Dec',
   ];
 
-// Search functionality
   final TextEditingController _searchController = TextEditingController();
   final FocusNode _searchFocusNode = FocusNode();
   String _searchQuery = '';

lib/screens/settings/library_settings_page.dart

@@ -117,7 +117,6 @@ class _LibrarySettingsPageState extends ConsumerState<LibrarySettingsPage> {
       return;
     }
 
-    // Check if folder exists
     if (!await Directory(libraryPath).exists()) {
       if (mounted) {
         ScaffoldMessenger.of(context).showSnackBar(

lib/services/history_database.dart

@@ -139,7 +139,6 @@ class HistoryDatabase {
     final prefs = await _prefs;
     final lastContainer = prefs.getString('ios_last_container_path');
     
-    // Skip if container hasn't changed
     if (lastContainer == _currentContainerPath) {
       _log.d('iOS container path unchanged, skipping migration');
       return false;

lib/services/library_database.dart

@@ -6,7 +6,6 @@ import 'package:spotiflac_android/utils/logger.dart';
 
 final _log = AppLogger('LibraryDatabase');
 
-/// Represents a track in the user's local music library
 class LocalLibraryItem {
   final String id;
   final String trackName;
@@ -14,7 +13,7 @@ class LocalLibraryItem {
   final String albumName;
   final String? albumArtist;
   final String filePath;
-  final String? coverPath; // Path to extracted cover art
+  final String? coverPath;
   final DateTime scannedAt;
   final String? isrc;
   final int? trackNumber;
@@ -92,7 +91,6 @@ class LocalLibraryItem {
   String get albumKey => '${albumName.toLowerCase()}|${(albumArtist ?? artistName).toLowerCase()}';
 }
 
-/// SQLite database service for local library
 class LibraryDatabase {
   static final LibraryDatabase instance = LibraryDatabase._init();
   static Database? _database;
@@ -144,7 +142,6 @@ class LibraryDatabase {
       )
     ''');
     
-    // Indexes for fast lookups
     await db.execute('CREATE INDEX idx_library_isrc ON library(isrc)');
     await db.execute('CREATE INDEX idx_library_track_artist ON library(track_name, artist_name)');
     await db.execute('CREATE INDEX idx_library_album ON library(album_name, album_artist)');
@@ -163,7 +160,6 @@ class LibraryDatabase {
     }
   }
   
-  /// Convert JSON format (camelCase) to DB row (snake_case)
   Map<String, dynamic> _jsonToDbRow(Map<String, dynamic> json) {
     return {
       'id': json['id'],
@@ -186,7 +182,6 @@ class LibraryDatabase {
     };
   }
   
-  /// Convert DB row (snake_case) to JSON format (camelCase)
   Map<String, dynamic> _dbRowToJson(Map<String, dynamic> row) {
     return {
       'id': row['id'],
@@ -209,9 +204,8 @@ class LibraryDatabase {
     };
   }
   
-  // ==================== CRUD Operations ====================
+  // CRUD Operations
   
-  /// Insert or update a library item
   Future<void> upsert(Map<String, dynamic> json) async {
     final db = await database;
     await db.insert(
@@ -221,7 +215,6 @@ class LibraryDatabase {
     );
   }
   
-  /// Batch insert multiple items
   Future<void> upsertBatch(List<Map<String, dynamic>> items) async {
     final db = await database;
     final batch = db.batch();
@@ -238,7 +231,6 @@ class LibraryDatabase {
     _log.i('Batch inserted ${items.length} items');
   }
   
-  /// Get all library items ordered by album/artist
   Future<List<Map<String, dynamic>>> getAll({int? limit, int? offset}) async {
     final db = await database;
     final rows = await db.query(
@@ -250,7 +242,6 @@ class LibraryDatabase {
     return rows.map(_dbRowToJson).toList();
   }
   
-  /// Get item by ID
   Future<Map<String, dynamic>?> getById(String id) async {
     final db = await database;
     final rows = await db.query(
@@ -263,7 +254,6 @@ class LibraryDatabase {
     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(
@@ -276,7 +266,6 @@ class LibraryDatabase {
     return _dbRowToJson(rows.first);
   }
   
-  /// Check if ISRC exists - O(1) with index
   Future<bool> existsByIsrc(String isrc) async {
     final db = await database;
     final result = await db.rawQuery(
@@ -286,7 +275,6 @@ class LibraryDatabase {
     return result.isNotEmpty;
   }
   
-  /// Find by track name and artist (fuzzy match)
   Future<List<Map<String, dynamic>>> findByTrackAndArtist(
     String trackName,
     String artistName,
@@ -300,7 +288,6 @@ class LibraryDatabase {
     return rows.map(_dbRowToJson).toList();
   }
   
-  /// Check if track exists by name and artist
   Future<Map<String, dynamic>?> findExisting({
     String? isrc,
     String? trackName,
@@ -321,7 +308,6 @@ class LibraryDatabase {
     return null;
   }
   
-  /// Get all ISRCs as Set for fast in-memory lookup
   Future<Set<String>> getAllIsrcs() async {
     final db = await database;
     final rows = await db.rawQuery(
@@ -330,7 +316,6 @@ class LibraryDatabase {
     return rows.map((r) => r['isrc'] as String).toSet();
   }
   
-  /// Get all track keys (name|artist) for matching
   Future<Set<String>> getAllTrackKeys() async {
     final db = await database;
     final rows = await db.rawQuery(
@@ -339,19 +324,16 @@ class LibraryDatabase {
     return rows.map((r) => r['match_key'] as String).toSet();
   }
   
-  /// Delete by file path
   Future<void> deleteByPath(String filePath) async {
     final db = await database;
     await db.delete('library', where: 'file_path = ?', whereArgs: [filePath]);
   }
   
-  /// Delete by ID
   Future<void> delete(String id) async {
     final db = await database;
     await db.delete('library', where: 'id = ?', whereArgs: [id]);
   }
   
-  /// Delete items where file no longer exists
   Future<int> cleanupMissingFiles() async {
     final db = await database;
     final rows = await db.query('library', columns: ['id', 'file_path']);
@@ -371,21 +353,18 @@ class LibraryDatabase {
     return removed;
   }
   
-  /// Clear all library data
   Future<void> clearAll() async {
     final db = await database;
     await db.delete('library');
     _log.i('Cleared all library data');
   }
   
-  /// Get total count
   Future<int> getCount() async {
     final db = await database;
     final result = await db.rawQuery('SELECT COUNT(*) as count FROM library');
     return Sqflite.firstIntValue(result) ?? 0;
   }
   
-  /// Search library by query
   Future<List<Map<String, dynamic>>> search(String query, {int limit = 50}) async {
     final db = await database;
     final searchQuery = '%${query.toLowerCase()}%';
@@ -399,7 +378,6 @@ class LibraryDatabase {
     return rows.map(_dbRowToJson).toList();
   }
   
-  /// Close database
   Future<void> close() async {
     final db = await database;
     await db.close();