refactor: clean up redundant comments and code

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();