feat: add file format library quality label

lib/l10n/app_localizations.dart

@@ -2206,6 +2206,12 @@ abstract class AppLocalizations {
   /// **'Audio quality'**
   String get trackAudioQuality;
 
+  /// Library audio quality label mode that shows the detected file format
+  ///
+  /// In en, this message translates to:
+  /// **'File format'**
+  String get libraryQualityLabelFileFormat;
+
   /// Metadata label - release date
   ///
   /// In en, this message translates to:

lib/l10n/app_localizations_de.dart

@@ -1203,6 +1203,9 @@ class AppLocalizationsDe extends AppLocalizations {
   @override
   String get trackAudioQuality => 'Audioqualität';
 
+  @override
+  String get libraryQualityLabelFileFormat => 'File format';
+
   @override
   String get trackReleaseDate => 'Erscheinungsdatum';
 

lib/l10n/app_localizations_en.dart

@@ -1188,6 +1188,9 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get trackAudioQuality => 'Audio quality';
 
+  @override
+  String get libraryQualityLabelFileFormat => 'File format';
+
   @override
   String get trackReleaseDate => 'Release date';
 

lib/l10n/app_localizations_es.dart

@@ -1188,6 +1188,9 @@ class AppLocalizationsEs extends AppLocalizations {
   @override
   String get trackAudioQuality => 'Audio quality';
 
+  @override
+  String get libraryQualityLabelFileFormat => 'File format';
+
   @override
   String get trackReleaseDate => 'Release date';
 

lib/l10n/app_localizations_fr.dart

@@ -1217,6 +1217,9 @@ class AppLocalizationsFr extends AppLocalizations {
   @override
   String get trackAudioQuality => 'Qualité audio';
 
+  @override
+  String get libraryQualityLabelFileFormat => 'File format';
+
   @override
   String get trackReleaseDate => 'Date de sortie';
 

lib/l10n/app_localizations_id.dart

@@ -1193,6 +1193,9 @@ class AppLocalizationsId extends AppLocalizations {
   @override
   String get trackAudioQuality => 'Kualitas audio';
 
+  @override
+  String get libraryQualityLabelFileFormat => 'Format berkas';
+
   @override
   String get trackReleaseDate => 'Tanggal rilis';
 

lib/l10n/app_localizations_ja.dart

@@ -1183,6 +1183,9 @@ class AppLocalizationsJa extends AppLocalizations {
   @override
   String get trackAudioQuality => 'オーディオ品質';
 
+  @override
+  String get libraryQualityLabelFileFormat => 'File format';
+
   @override
   String get trackReleaseDate => 'リリース日';
 

lib/l10n/app_localizations_ko.dart

@@ -1162,6 +1162,9 @@ class AppLocalizationsKo extends AppLocalizations {
   @override
   String get trackAudioQuality => '오디오 음질';
 
+  @override
+  String get libraryQualityLabelFileFormat => 'File format';
+
   @override
   String get trackReleaseDate => '발매일자';
 

lib/l10n/app_localizations_pt.dart

@@ -1188,6 +1188,9 @@ class AppLocalizationsPt extends AppLocalizations {
   @override
   String get trackAudioQuality => 'Audio quality';
 
+  @override
+  String get libraryQualityLabelFileFormat => 'File format';
+
   @override
   String get trackReleaseDate => 'Release date';
 

lib/l10n/app_localizations_ru.dart

@@ -1194,6 +1194,9 @@ class AppLocalizationsRu extends AppLocalizations {
   @override
   String get trackAudioQuality => 'Качество записи';
 
+  @override
+  String get libraryQualityLabelFileFormat => 'File format';
+
   @override
   String get trackReleaseDate => 'Дата выхода';
 

lib/l10n/app_localizations_tr.dart

@@ -1199,6 +1199,9 @@ class AppLocalizationsTr extends AppLocalizations {
   @override
   String get trackAudioQuality => 'Ses kalitesi';
 
+  @override
+  String get libraryQualityLabelFileFormat => 'File format';
+
   @override
   String get trackReleaseDate => 'Yayın tarihi';
 

lib/l10n/app_localizations_uk.dart

@@ -1203,6 +1203,9 @@ class AppLocalizationsUk extends AppLocalizations {
   @override
   String get trackAudioQuality => 'Якість звуку';
 
+  @override
+  String get libraryQualityLabelFileFormat => 'File format';
+
   @override
   String get trackReleaseDate => 'Дата випуску';
 

lib/l10n/arb/app_en.arb

@@ -1568,6 +1568,10 @@
   "@trackAudioQuality": {
     "description": "Metadata label - audio quality"
   },
+  "libraryQualityLabelFileFormat": "File format",
+  "@libraryQualityLabelFileFormat": {
+    "description": "Library audio quality label mode that shows the detected file format"
+  },
   "trackReleaseDate": "Release date",
   "@trackReleaseDate": {
     "description": "Metadata label - release date"

lib/l10n/arb/app_id.arb

@@ -2164,6 +2164,7 @@
   "@trackAudioQuality": {
     "description": "Metadata label - audio quality"
   },
+  "libraryQualityLabelFileFormat": "Format berkas",
   "libraryRemovedMissingFiles": "Removed {count} missing files from library",
   "@libraryRemovedMissingFiles": {
     "description": "Snackbar after cleanup",

lib/models/settings.dart

@@ -7,6 +7,7 @@ part 'settings.g.dart';
 class AppSettings {
   static const String homeFeedProviderOff = '__off__';
   static const String libraryQualityLabelBitrate = 'bitrate';
+  static const String libraryQualityLabelFileFormat = 'file_format';
   static const String libraryQualityLabelBitDepthOnly = 'bit_depth_only';
   static const String libraryQualityLabelBitDepth = 'bit_depth';
   static const String libraryQualityLabelBitDepthBitrate = 'bit_depth_bitrate';
@@ -42,8 +43,8 @@ class AppSettings {
   /// 'last' (keep last used), 'all', 'albums', 'singles', or 'playlists'.
   final String defaultLibraryView;
 
-  /// Library badge text: measured bitrate, bit depth, bit depth/sample rate,
-  /// or the combined bit depth/bitrate label.
+  /// Library badge text: measured bitrate, file format, bit depth,
+  /// bit depth/sample rate, or the combined bit depth/bitrate label.
   final String libraryQualityLabelMode;
   final bool askQualityBeforeDownload;
   final bool enableLogging;

lib/providers/settings_provider.dart

@@ -381,6 +381,8 @@ class SettingsNotifier extends Notifier<AppSettings> {
 
   String _normalizeLibraryQualityLabelMode(String value) {
     return switch (value) {
+      AppSettings.libraryQualityLabelFileFormat =>
+        AppSettings.libraryQualityLabelFileFormat,
       AppSettings.libraryQualityLabelBitDepthOnly =>
         AppSettings.libraryQualityLabelBitDepthOnly,
       AppSettings.libraryQualityLabelBitDepth =>

lib/screens/settings/library_settings_page.dart

@@ -435,6 +435,9 @@ class _LibrarySettingsPageState extends ConsumerState<LibrarySettingsPage> {
   }
 
   String _getQualityLabelModeLabel(BuildContext context, String mode) {
+    if (mode == AppSettings.libraryQualityLabelFileFormat) {
+      return context.l10n.libraryQualityLabelFileFormat;
+    }
     if (mode == AppSettings.libraryQualityLabelBitDepthOnly) {
       return context.l10n.audioAnalysisBitDepth;
     }
@@ -474,6 +477,11 @@ class _LibrarySettingsPageState extends ConsumerState<LibrarySettingsPage> {
         '${context.l10n.audioAnalysisBitDepth} & '
             '${context.l10n.trackConvertBitrate}',
       ),
+      (
+        AppSettings.libraryQualityLabelFileFormat,
+        Icons.audio_file_rounded,
+        context.l10n.libraryQualityLabelFileFormat,
+      ),
     ];
     showModalBottomSheet<void>(
       context: context,

lib/screens/settings/settings_search_catalog.dart

@@ -149,7 +149,16 @@ class SettingsSearchCatalog {
         SettingsSearchEntry(
           icon: Icons.graphic_eq_rounded,
           title: l10n.trackAudioQuality,
-          keywords: const ['quality label', 'bitrate', 'bit depth', 'kbps'],
+          keywords: const [
+            'quality label',
+            'bitrate',
+            'bit depth',
+            'file format',
+            'codec',
+            'flac',
+            'mp3',
+            'kbps',
+          ],
         ),
         SettingsSearchEntry(
           icon: Icons.library_music_outlined,

lib/utils/audio_quality_badge_policy.dart

@@ -11,6 +11,8 @@ final RegExp _bitDepthQualityPattern = RegExp(
 
 String normalizeLibraryQualityLabelMode(String? mode) {
   return switch (mode) {
+    AppSettings.libraryQualityLabelFileFormat =>
+      AppSettings.libraryQualityLabelFileFormat,
     AppSettings.libraryQualityLabelBitDepthOnly =>
       AppSettings.libraryQualityLabelBitDepthOnly,
     AppSettings.libraryQualityLabelBitDepth =>
@@ -21,9 +23,29 @@ String normalizeLibraryQualityLabelMode(String? mode) {
   };
 }
 
+String? _libraryFileFormatLabel(String? format) {
+  final rawFormat = normalizeOptionalString(format);
+  if (rawFormat == null) return null;
+
+  return switch (normalizeAudioFormatValue(rawFormat)) {
+    'flac' => 'FLAC',
+    'alac' => 'ALAC',
+    'wav' => 'WAV',
+    'aiff' => 'AIFF',
+    'aac' => 'AAC',
+    'eac3' => 'EAC3',
+    'ac3' => 'AC3',
+    'ac4' => 'AC4',
+    'mp3' => 'MP3',
+    'opus' => 'OPUS',
+    'm4a' => 'M4A',
+    _ => rawFormat.replaceFirst(RegExp(r'^\.'), '').toUpperCase(),
+  };
+}
+
 /// Builds a Library label from metadata already held in memory. Lossy formats
-/// keep their bitrate label because bit depth is not a useful quality signal
-/// for encoded MP3/AAC/Opus audio.
+/// keep their bitrate label in quality modes because bit depth is not a useful
+/// quality signal for encoded MP3/AAC/Opus audio.
 String? buildLibraryAudioQualityLabel({
   required String mode,
   String? format,
@@ -53,6 +75,10 @@ String? buildLibraryAudioQualityLabel({
       : null;
   final normalizedMode = normalizeLibraryQualityLabelMode(mode);
 
+  if (normalizedMode == AppSettings.libraryQualityLabelFileFormat) {
+    return _libraryFileFormatLabel(format);
+  }
+
   if (isLossyAudioFormat(format)) {
     return bitrateLabel;
   }

test/audio_quality_badge_policy_test.dart

@@ -54,6 +54,48 @@ void main() {
       );
     });
 
+    test('shows detected file format without quality metrics', () {
+      expect(
+        normalizeLibraryQualityLabelMode(
+          AppSettings.libraryQualityLabelFileFormat,
+        ),
+        AppSettings.libraryQualityLabelFileFormat,
+      );
+      expect(
+        buildLibraryAudioQualityLabel(
+          mode: AppSettings.libraryQualityLabelFileFormat,
+          format: 'flac',
+          bitrateKbps: 1760,
+          bitDepth: 24,
+          sampleRate: 96000,
+        ),
+        'FLAC',
+      );
+      expect(
+        buildLibraryAudioQualityLabel(
+          mode: AppSettings.libraryQualityLabelFileFormat,
+          format: 'm4a',
+          bitrateKbps: 256,
+        ),
+        'M4A',
+      );
+      expect(
+        buildLibraryAudioQualityLabel(
+          mode: AppSettings.libraryQualityLabelFileFormat,
+          format: 'mp3',
+          bitrateKbps: 320,
+        ),
+        'MP3',
+      );
+      expect(
+        buildLibraryAudioQualityLabel(
+          mode: AppSettings.libraryQualityLabelFileFormat,
+          format: 'ape',
+        ),
+        'APE',
+      );
+    });
+
     test('shows only bit depth when requested', () {
       expect(
         buildLibraryAudioQualityLabel(