feat: audio analysis rescan and AAC conversion support

Audio Analysis:
- Add rescan capability by bumping cache version
- Display channel layout (stereo, 5.1, etc.) and bitrate
- Use astats filter for more accurate peak/RMS measurements
- Support more formats: mp4, ac3, eac3, mka, wv, ape, tta, aif
- Only report bit depth for codecs that store it (FLAC, ALAC, WAV)
- Validate cache for SAF content:// URIs

Conversion:
- Add AAC as conversion target format
- Recognize ALAC as lossless source
- Prevent accidental deletion when source and target URI match
- Store format and bitrate in database after conversion

Utilities:
- Add audio_conversion_utils.dart for centralized conversion logic
- Add isSameContentUri() helper for safe URI comparison

lib/screens/downloaded_album_screen.dart

@@ -10,6 +10,7 @@ import 'package:spotiflac_android/services/ffmpeg_service.dart';
 import 'package:spotiflac_android/services/platform_bridge.dart';
 import 'package:spotiflac_android/services/history_database.dart';
 import 'package:spotiflac_android/l10n/l10n.dart';
+import 'package:spotiflac_android/utils/audio_conversion_utils.dart';
 import 'package:spotiflac_android/utils/file_access.dart';
 import 'package:spotiflac_android/utils/image_cache_utils.dart';
 import 'package:spotiflac_android/utils/lyrics_metadata_helper.dart';
@@ -950,8 +951,12 @@ class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
           : item.filePath.toLowerCase();
       final ext = nameToCheck.endsWith('.flac')
           ? 'FLAC'
+          : nameToCheck.endsWith('.alac')
+          ? 'ALAC'
           : nameToCheck.endsWith('.m4a')
           ? 'M4A'
+          : (nameToCheck.endsWith('.aac') || nameToCheck.endsWith('.mp4a'))
+          ? 'AAC'
           : nameToCheck.endsWith('.mp3')
           ? 'MP3'
           : (nameToCheck.endsWith('.opus') || nameToCheck.endsWith('.ogg'))
@@ -960,11 +965,11 @@ class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
       if (ext != null) sourceFormats.add(ext);
     }
 
-    final formats = ['ALAC', 'FLAC', 'MP3', 'Opus'].where((target) {
+    final formats = ['ALAC', 'FLAC', 'AAC', 'MP3', 'Opus'].where((target) {
       return sourceFormats.any((src) {
         if (src == target) return false;
         final isLosslessTarget = target == 'ALAC' || target == 'FLAC';
-        final isLosslessSource = src == 'FLAC' || src == 'M4A';
+        final isLosslessSource = src == 'FLAC' || src == 'ALAC' || src == 'M4A';
         if (isLosslessTarget && !isLosslessSource) return false;
         return true;
       });
@@ -975,9 +980,15 @@ class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
     String selectedFormat = formats.first;
     bool isLosslessTarget =
         selectedFormat == 'ALAC' || selectedFormat == 'FLAC';
+    String defaultBitrateForFormat(String format) {
+      if (format == 'Opus') return '128k';
+      if (format == 'AAC') return '256k';
+      return '320k';
+    }
+
     String selectedBitrate = isLosslessTarget
         ? '320k'
-        : (selectedFormat == 'Opus' ? '128k' : '320k');
+        : defaultBitrateForFormat(selectedFormat);
 
     showModalBottomSheet<void>(
       context: context,
@@ -1039,9 +1050,9 @@ class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
                                 isLosslessTarget =
                                     format == 'ALAC' || format == 'FLAC';
                                 if (!isLosslessTarget) {
-                                  selectedBitrate = format == 'Opus'
-                                      ? '128k'
-                                      : '320k';
+                                  selectedBitrate = defaultBitrateForFormat(
+                                    format,
+                                  );
                                 }
                               });
                             }
@@ -1316,6 +1327,7 @@ class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
                 mimeType = 'audio/opus';
                 break;
               case 'alac':
+              case 'aac':
                 newExt = '.m4a';
                 mimeType = 'audio/mp4';
                 break;
@@ -1350,14 +1362,21 @@ class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
               continue;
             }
 
-            try {
-              await PlatformBridge.safDelete(item.filePath);
-            } catch (_) {}
+            if (!isSameContentUri(item.filePath, safUri)) {
+              try {
+                await PlatformBridge.safDelete(item.filePath);
+              } catch (_) {}
+            }
             await historyDb.updateFilePath(
               item.id,
               safUri,
               newSafFileName: newFileName,
               newQuality: newQuality,
+              newFormat: normalizedConvertedAudioFormat(targetFormat),
+              newBitrate: convertedAudioBitrateKbps(
+                targetFormat: targetFormat,
+                bitrate: bitrate,
+              ),
               clearAudioSpecs: true,
             );
           }
@@ -1374,6 +1393,11 @@ class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
             item.id,
             newPath,
             newQuality: newQuality,
+            newFormat: normalizedConvertedAudioFormat(targetFormat),
+            newBitrate: convertedAudioBitrateKbps(
+              targetFormat: targetFormat,
+              bitrate: bitrate,
+            ),
             clearAudioSpecs: true,
           );
         }

lib/screens/local_album_screen.dart

@@ -8,6 +8,7 @@ import 'package:spotiflac_android/models/track.dart';
 import 'package:spotiflac_android/providers/download_queue_provider.dart';
 import 'package:spotiflac_android/providers/extension_provider.dart';
 import 'package:spotiflac_android/providers/settings_provider.dart';
+import 'package:spotiflac_android/utils/audio_conversion_utils.dart';
 import 'package:spotiflac_android/utils/file_access.dart';
 import 'package:spotiflac_android/utils/image_cache_utils.dart';
 import 'package:spotiflac_android/utils/lyrics_metadata_helper.dart';
@@ -1176,52 +1177,38 @@ class _LocalAlbumScreenState extends ConsumerState<LocalAlbumScreen> {
     for (final id in _selectedIds) {
       final item = tracksById[id];
       if (item == null) continue;
-      String? ext;
-      if (item.format != null && item.format!.isNotEmpty) {
-        final fmt = item.format!.toLowerCase();
-        if (fmt == 'flac') {
-          ext = 'FLAC';
-        } else if (fmt == 'm4a') {
-          ext = 'M4A';
-        } else if (fmt == 'mp3') {
-          ext = 'MP3';
-        } else if (fmt == 'opus' || fmt == 'ogg') {
-          ext = 'Opus';
-        }
-      }
-      if (ext == null) {
-        final lower = item.filePath.toLowerCase();
-        if (lower.endsWith('.flac')) {
-          ext = 'FLAC';
-        } else if (lower.endsWith('.m4a')) {
-          ext = 'M4A';
-        } else if (lower.endsWith('.mp3')) {
-          ext = 'MP3';
-        } else if (lower.endsWith('.opus') || lower.endsWith('.ogg')) {
-          ext = 'Opus';
-        }
-      }
-      if (ext != null) sourceFormats.add(ext);
+      final sourceFormat = convertibleAudioSourceFormat(
+        storedFormat: item.format,
+        filePath: item.filePath,
+      );
+      if (sourceFormat != null) sourceFormats.add(sourceFormat);
     }
 
-    final formats = ['ALAC', 'FLAC', 'MP3', 'Opus'].where((target) {
-      return sourceFormats.any((src) {
-        if (src == target) return false;
-        final isLosslessTarget = target == 'ALAC' || target == 'FLAC';
-        final isLosslessSource = src == 'FLAC' || src == 'M4A';
-        if (isLosslessTarget && !isLosslessSource) return false;
-        return true;
-      });
-    }).toList();
+    final formats = audioConversionTargetFormats
+        .where(
+          (target) => sourceFormats.any(
+            (source) => canConvertAudioFormat(
+              sourceFormat: source,
+              targetFormat: target,
+            ),
+          ),
+        )
+        .toList();
 
     if (formats.isEmpty) return;
 
     String selectedFormat = formats.first;
     bool isLosslessTarget =
         selectedFormat == 'ALAC' || selectedFormat == 'FLAC';
+    String defaultBitrateForFormat(String format) {
+      if (format == 'Opus') return '128k';
+      if (format == 'AAC') return '256k';
+      return '320k';
+    }
+
     String selectedBitrate = isLosslessTarget
         ? '320k'
-        : (selectedFormat == 'Opus' ? '128k' : '320k');
+        : defaultBitrateForFormat(selectedFormat);
 
     showModalBottomSheet<void>(
       context: context,
@@ -1283,9 +1270,9 @@ class _LocalAlbumScreenState extends ConsumerState<LocalAlbumScreen> {
                                 isLosslessTarget =
                                     format == 'ALAC' || format == 'FLAC';
                                 if (!isLosslessTarget) {
-                                  selectedBitrate = format == 'Opus'
-                                      ? '128k'
-                                      : '320k';
+                                  selectedBitrate = defaultBitrateForFormat(
+                                    format,
+                                  );
                                 }
                               });
                             }
@@ -1381,39 +1368,17 @@ class _LocalAlbumScreenState extends ConsumerState<LocalAlbumScreen> {
     for (final id in _selectedIds) {
       final item = tracksById[id];
       if (item == null) continue;
-      // Detect current format: prefer item.format field (works for SAF too),
-      // fall back to file extension for regular paths
-      String? currentFormat;
-      if (item.format != null && item.format!.isNotEmpty) {
-        final fmt = item.format!.toLowerCase();
-        if (fmt == 'flac') {
-          currentFormat = 'FLAC';
-        } else if (fmt == 'm4a') {
-          currentFormat = 'M4A';
-        } else if (fmt == 'mp3') {
-          currentFormat = 'MP3';
-        } else if (fmt == 'opus' || fmt == 'ogg') {
-          currentFormat = 'Opus';
-        }
+      final currentFormat = convertibleAudioSourceFormat(
+        storedFormat: item.format,
+        filePath: item.filePath,
+      );
+      if (currentFormat == null ||
+          !canConvertAudioFormat(
+            sourceFormat: currentFormat,
+            targetFormat: targetFormat,
+          )) {
+        continue;
       }
-      if (currentFormat == null) {
-        // Fallback: try file extension (works for regular paths)
-        final lower = item.filePath.toLowerCase();
-        if (lower.endsWith('.flac')) {
-          currentFormat = 'FLAC';
-        } else if (lower.endsWith('.m4a')) {
-          currentFormat = 'M4A';
-        } else if (lower.endsWith('.mp3')) {
-          currentFormat = 'MP3';
-        } else if (lower.endsWith('.opus') || lower.endsWith('.ogg')) {
-          currentFormat = 'Opus';
-        }
-      }
-      if (currentFormat == null || currentFormat == targetFormat) continue;
-      final isLosslessTarget = targetFormat == 'ALAC' || targetFormat == 'FLAC';
-      final isLosslessSource =
-          currentFormat == 'FLAC' || currentFormat == 'M4A';
-      if (isLosslessTarget && !isLosslessSource) continue;
       selected.add(item);
     }
 
@@ -1608,6 +1573,7 @@ class _LocalAlbumScreenState extends ConsumerState<LocalAlbumScreen> {
                 mimeType = 'audio/opus';
                 break;
               case 'alac':
+              case 'aac':
                 newExt = '.m4a';
                 mimeType = 'audio/mp4';
                 break;
@@ -1642,9 +1608,11 @@ class _LocalAlbumScreenState extends ConsumerState<LocalAlbumScreen> {
               continue;
             }
 
-            try {
-              await PlatformBridge.safDelete(item.filePath);
-            } catch (_) {}
+            if (!isSameContentUri(item.filePath, safUri)) {
+              try {
+                await PlatformBridge.safDelete(item.filePath);
+              } catch (_) {}
+            }
             await localDb.replaceWithConvertedItem(
               item: item,
               newFilePath: safUri,

lib/screens/queue_tab.dart

@@ -10,6 +10,7 @@ import 'package:spotiflac_android/services/ffmpeg_service.dart';
 import 'package:spotiflac_android/services/platform_bridge.dart';
 import 'package:spotiflac_android/l10n/l10n.dart';
 import 'package:spotiflac_android/utils/app_bar_layout.dart';
+import 'package:spotiflac_android/utils/audio_conversion_utils.dart';
 import 'package:spotiflac_android/utils/file_access.dart';
 import 'package:spotiflac_android/utils/lyrics_metadata_helper.dart';
 import 'package:spotiflac_android/models/download_item.dart';
@@ -4839,46 +4840,39 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     for (final id in _selectedIds) {
       final item = itemsById[id];
       if (item == null) continue;
-      String nameToCheck;
-      if (item.historyItem?.safFileName != null &&
-          item.historyItem!.safFileName!.isNotEmpty) {
-        nameToCheck = item.historyItem!.safFileName!.toLowerCase();
-      } else if (item.localItem?.format != null &&
-          item.localItem!.format!.isNotEmpty) {
-        nameToCheck = '.${item.localItem!.format!.toLowerCase()}';
-      } else {
-        nameToCheck = item.filePath.toLowerCase();
-      }
-      final ext = nameToCheck.endsWith('.flac')
-          ? 'FLAC'
-          : nameToCheck.endsWith('.m4a')
-          ? 'M4A'
-          : nameToCheck.endsWith('.mp3')
-          ? 'MP3'
-          : (nameToCheck.endsWith('.opus') || nameToCheck.endsWith('.ogg'))
-          ? 'Opus'
-          : null;
-      if (ext != null) sourceFormats.add(ext);
+      final sourceFormat = convertibleAudioSourceFormat(
+        storedFormat: item.localItem?.format ?? item.historyItem?.format,
+        filePath: item.filePath,
+        fileName: item.historyItem?.safFileName,
+      );
+      if (sourceFormat != null) sourceFormats.add(sourceFormat);
     }
 
-    final formats = ['ALAC', 'FLAC', 'MP3', 'Opus'].where((target) {
-      return sourceFormats.any((src) {
-        if (src == target) return false;
-        final isLosslessTarget = target == 'ALAC' || target == 'FLAC';
-        final isLosslessSource = src == 'FLAC' || src == 'M4A';
-        if (isLosslessTarget && !isLosslessSource) return false;
-        return true;
-      });
-    }).toList();
+    final formats = audioConversionTargetFormats
+        .where(
+          (target) => sourceFormats.any(
+            (source) => canConvertAudioFormat(
+              sourceFormat: source,
+              targetFormat: target,
+            ),
+          ),
+        )
+        .toList();
 
     if (formats.isEmpty) return;
 
     String selectedFormat = formats.first;
     bool isLosslessTarget =
         selectedFormat == 'ALAC' || selectedFormat == 'FLAC';
+    String defaultBitrateForFormat(String format) {
+      if (format == 'Opus') return '128k';
+      if (format == 'AAC') return '256k';
+      return '320k';
+    }
+
     String selectedBitrate = isLosslessTarget
         ? '320k'
-        : (selectedFormat == 'Opus' ? '128k' : '320k');
+        : defaultBitrateForFormat(selectedFormat);
     var didStartConversion = false;
 
     _hideSelectionOverlay();
@@ -4944,9 +4938,9 @@ class _QueueTabState extends ConsumerState<QueueTab> {
                                 isLosslessTarget =
                                     format == 'ALAC' || format == 'FLAC';
                                 if (!isLosslessTarget) {
-                                  selectedBitrate = format == 'Opus'
-                                      ? '128k'
-                                      : '320k';
+                                  selectedBitrate = defaultBitrateForFormat(
+                                    format,
+                                  );
                                 }
                               });
                             }
@@ -5057,29 +5051,18 @@ class _QueueTabState extends ConsumerState<QueueTab> {
     for (final id in _selectedIds) {
       final item = itemsById[id];
       if (item == null) continue;
-      String nameToCheck;
-      if (item.historyItem?.safFileName != null &&
-          item.historyItem!.safFileName!.isNotEmpty) {
-        nameToCheck = item.historyItem!.safFileName!.toLowerCase();
-      } else if (item.localItem?.format != null &&
-          item.localItem!.format!.isNotEmpty) {
-        nameToCheck = '.${item.localItem!.format!.toLowerCase()}';
-      } else {
-        nameToCheck = item.filePath.toLowerCase();
+      final sourceFormat = convertibleAudioSourceFormat(
+        storedFormat: item.localItem?.format ?? item.historyItem?.format,
+        filePath: item.filePath,
+        fileName: item.historyItem?.safFileName,
+      );
+      if (sourceFormat == null ||
+          !canConvertAudioFormat(
+            sourceFormat: sourceFormat,
+            targetFormat: targetFormat,
+          )) {
+        continue;
       }
-      final ext = nameToCheck.endsWith('.flac')
-          ? 'FLAC'
-          : nameToCheck.endsWith('.m4a')
-          ? 'M4A'
-          : nameToCheck.endsWith('.mp3')
-          ? 'MP3'
-          : (nameToCheck.endsWith('.opus') || nameToCheck.endsWith('.ogg'))
-          ? 'Opus'
-          : null;
-      if (ext == null || ext == targetFormat) continue;
-      final isLosslessTarget = targetFormat == 'ALAC' || targetFormat == 'FLAC';
-      final isLosslessSource = ext == 'FLAC' || ext == 'M4A';
-      if (isLosslessTarget && !isLosslessSource) continue;
       selectedItems.add(item);
     }
 
@@ -5247,6 +5230,7 @@ class _QueueTabState extends ConsumerState<QueueTab> {
                 mimeType = 'audio/opus';
                 break;
               case 'alac':
+              case 'aac':
                 newExt = '.m4a';
                 mimeType = 'audio/mp4';
                 break;
@@ -5281,15 +5265,22 @@ class _QueueTabState extends ConsumerState<QueueTab> {
               continue;
             }
 
-            try {
-              await PlatformBridge.safDelete(item.filePath);
-            } catch (_) {}
+            if (!isSameContentUri(item.filePath, safUri)) {
+              try {
+                await PlatformBridge.safDelete(item.filePath);
+              } catch (_) {}
+            }
 
             await historyDb.updateFilePath(
               hi.id,
               safUri,
               newSafFileName: newFileName,
               newQuality: newQuality,
+              newFormat: normalizedConvertedAudioFormat(targetFormat),
+              newBitrate: convertedAudioBitrateKbps(
+                targetFormat: targetFormat,
+                bitrate: bitrate,
+              ),
               clearAudioSpecs: true,
             );
           }
@@ -5352,6 +5343,7 @@ class _QueueTabState extends ConsumerState<QueueTab> {
                 mimeType = 'audio/opus';
                 break;
               case 'alac':
+              case 'aac':
                 newExt = '.m4a';
                 mimeType = 'audio/mp4';
                 break;
@@ -5386,9 +5378,11 @@ class _QueueTabState extends ConsumerState<QueueTab> {
               continue;
             }
 
-            try {
-              await PlatformBridge.safDelete(item.filePath);
-            } catch (_) {}
+            if (!isSameContentUri(item.filePath, safUri)) {
+              try {
+                await PlatformBridge.safDelete(item.filePath);
+              } catch (_) {}
+            }
             await LibraryDatabase.instance.replaceWithConvertedItem(
               item: item.localItem!,
               newFilePath: safUri,
@@ -5410,6 +5404,11 @@ class _QueueTabState extends ConsumerState<QueueTab> {
             item.historyItem!.id,
             newPath,
             newQuality: newQuality,
+            newFormat: normalizedConvertedAudioFormat(targetFormat),
+            newBitrate: convertedAudioBitrateKbps(
+              targetFormat: targetFormat,
+              bitrate: bitrate,
+            ),
             clearAudioSpecs: true,
           );
         } else if (item.localItem != null) {

lib/screens/track_metadata_screen.dart

@@ -17,6 +17,7 @@ import 'package:spotiflac_android/providers/settings_provider.dart';
 import 'package:spotiflac_android/services/platform_bridge.dart';
 import 'package:spotiflac_android/services/ffmpeg_service.dart';
 import 'package:spotiflac_android/l10n/l10n.dart';
+import 'package:spotiflac_android/utils/audio_conversion_utils.dart';
 import 'package:spotiflac_android/utils/logger.dart';
 import 'package:spotiflac_android/utils/lyrics_metadata_helper.dart';
 import 'package:spotiflac_android/utils/mime_utils.dart';
@@ -3375,6 +3376,7 @@ class _TrackMetadataScreenState extends ConsumerState<TrackMetadataScreen> {
     final lower = cleanFilePath.toLowerCase();
     return lower.endsWith('.flac') ||
         lower.endsWith('.m4a') ||
+        lower.endsWith('.aac') ||
         lower.endsWith('.mp3') ||
         lower.endsWith('.opus') ||
         lower.endsWith('.ogg');
@@ -3409,8 +3411,12 @@ class _TrackMetadataScreenState extends ConsumerState<TrackMetadataScreen> {
         case 'flac':
           return 'FLAC';
         case 'alac':
+          return 'ALAC';
         case 'm4a':
           return 'M4A';
+        case 'aac':
+        case 'mp4a':
+          return 'AAC';
         case 'mp3':
           return 'MP3';
         case 'opus':
@@ -3421,6 +3427,7 @@ class _TrackMetadataScreenState extends ConsumerState<TrackMetadataScreen> {
     final lower = cleanFilePath.toLowerCase();
     if (lower.endsWith('.flac')) return 'FLAC';
     if (lower.endsWith('.m4a')) return 'M4A';
+    if (lower.endsWith('.aac')) return 'AAC';
     if (lower.endsWith('.mp3')) return 'MP3';
     if (lower.endsWith('.opus') || lower.endsWith('.ogg')) return 'Opus';
     if (lower.endsWith('.cue')) return 'CUE';
@@ -3554,8 +3561,12 @@ class _TrackMetadataScreenState extends ConsumerState<TrackMetadataScreen> {
     final formats = <String>[];
     if (currentFormat == 'FLAC') {
       formats.addAll(['ALAC', 'AAC', 'MP3', 'Opus']);
-    } else if (currentFormat == 'M4A') {
+    } else if (currentFormat == 'ALAC') {
       formats.addAll(['FLAC', 'AAC', 'MP3', 'Opus']);
+    } else if (currentFormat == 'M4A') {
+      formats.addAll(['ALAC', 'FLAC', 'AAC', 'MP3', 'Opus']);
+    } else if (currentFormat == 'AAC') {
+      formats.addAll(['MP3', 'Opus']);
     } else if (currentFormat == 'MP3') {
       formats.addAll(['AAC', 'Opus']);
     } else if (currentFormat == 'Opus') {
@@ -4448,11 +4459,15 @@ class _TrackMetadataScreenState extends ConsumerState<TrackMetadataScreen> {
           return;
         }
 
-        final deletedOriginal = await PlatformBridge.safDelete(
-          cleanFilePath,
-        ).catchError((_) => false);
-        if (deletedOriginal != true) {
-          _log.w('Converted SAF file created but failed deleting original URI');
+        if (!isSameContentUri(cleanFilePath, safUri)) {
+          final deletedOriginal = await PlatformBridge.safDelete(
+            cleanFilePath,
+          ).catchError((_) => false);
+          if (deletedOriginal != true) {
+            _log.w(
+              'Converted SAF file created but failed deleting original URI',
+            );
+          }
         }
 
         if (!_isLocalItem) {
@@ -4461,6 +4476,11 @@ class _TrackMetadataScreenState extends ConsumerState<TrackMetadataScreen> {
             safUri,
             newSafFileName: newFileName,
             newQuality: newQuality,
+            newFormat: normalizedConvertedAudioFormat(targetFormat),
+            newBitrate: convertedAudioBitrateKbps(
+              targetFormat: targetFormat,
+              bitrate: bitrate,
+            ),
             clearAudioSpecs: true,
           );
           await ref.read(downloadHistoryProvider.notifier).reloadFromStorage();
@@ -4488,6 +4508,11 @@ class _TrackMetadataScreenState extends ConsumerState<TrackMetadataScreen> {
             _downloadItem!.id,
             newPath,
             newQuality: newQuality,
+            newFormat: normalizedConvertedAudioFormat(targetFormat),
+            newBitrate: convertedAudioBitrateKbps(
+              targetFormat: targetFormat,
+              bitrate: bitrate,
+            ),
             clearAudioSpecs: true,
           );
           await ref.read(downloadHistoryProvider.notifier).reloadFromStorage();

lib/services/history_database.dart

@@ -925,6 +925,8 @@ class HistoryDatabase {
     String? newQuality,
     int? newBitDepth,
     int? newSampleRate,
+    int? newBitrate,
+    String? newFormat,
     bool clearAudioSpecs = false,
   }) async {
     final db = await database;
@@ -935,9 +937,18 @@ class HistoryDatabase {
     if (newQuality != null) {
       values['quality'] = newQuality;
     }
+    if (newFormat != null) {
+      values['format'] = newFormat;
+    }
+    if (newBitrate != null) {
+      values['bitrate'] = newBitrate;
+    }
     if (clearAudioSpecs) {
       values['bit_depth'] = null;
       values['sample_rate'] = null;
+      if (newBitrate == null) {
+        values['bitrate'] = null;
+      }
     } else {
       if (newBitDepth != null) {
         values['bit_depth'] = newBitDepth;

lib/utils/audio_conversion_utils.dart

@@ -0,0 +1,105 @@
+const List<String> audioConversionTargetFormats = [
+  'ALAC',
+  'FLAC',
+  'AAC',
+  'MP3',
+  'Opus',
+];
+
+bool isLosslessConversionTarget(String targetFormat) {
+  final normalized = targetFormat.trim().toLowerCase();
+  return normalized == 'alac' || normalized == 'flac';
+}
+
+bool isLosslessConversionSource(String sourceFormat) {
+  switch (sourceFormat.trim().toUpperCase()) {
+    case 'FLAC':
+    case 'ALAC':
+    case 'M4A':
+      return true;
+    default:
+      return false;
+  }
+}
+
+bool canConvertAudioFormat({
+  required String sourceFormat,
+  required String targetFormat,
+}) {
+  if (sourceFormat.trim().toUpperCase() == targetFormat.trim().toUpperCase()) {
+    return false;
+  }
+  if (isLosslessConversionTarget(targetFormat) &&
+      !isLosslessConversionSource(sourceFormat)) {
+    return false;
+  }
+  return true;
+}
+
+String? convertibleAudioSourceFormat({
+  String? storedFormat,
+  String? filePath,
+  String? fileName,
+}) {
+  final fromStored = _convertibleAudioFormatLabel(storedFormat);
+  if (fromStored != null) return fromStored;
+
+  final name = (fileName != null && fileName.trim().isNotEmpty)
+      ? fileName
+      : filePath;
+  if (name == null || name.trim().isEmpty) return null;
+
+  final normalizedName = name.trim().toLowerCase();
+  final dotIndex = normalizedName.lastIndexOf('.');
+  if (dotIndex < 0 || dotIndex == normalizedName.length - 1) {
+    return null;
+  }
+  return _convertibleAudioFormatLabel(normalizedName.substring(dotIndex + 1));
+}
+
+String? _convertibleAudioFormatLabel(String? rawFormat) {
+  final format = rawFormat?.trim().toLowerCase();
+  if (format == null || format.isEmpty) return null;
+
+  switch (format) {
+    case 'flac':
+      return 'FLAC';
+    case 'alac':
+      return 'ALAC';
+    case 'm4a':
+    case 'mp4':
+      return 'M4A';
+    case 'aac':
+    case 'mp4a':
+      return 'AAC';
+    case 'mp3':
+      return 'MP3';
+    case 'opus':
+    case 'ogg':
+      return 'Opus';
+    case 'eac3':
+    case 'ec-3':
+      return 'EAC3';
+    case 'ac3':
+    case 'ac-3':
+      return 'AC3';
+    case 'ac4':
+    case 'ac-4':
+      return 'AC4';
+    default:
+      return null;
+  }
+}
+
+String normalizedConvertedAudioFormat(String targetFormat) {
+  return targetFormat.trim().toLowerCase();
+}
+
+int? convertedAudioBitrateKbps({
+  required String targetFormat,
+  required String bitrate,
+}) {
+  if (isLosslessConversionTarget(targetFormat)) return null;
+  final match = RegExp(r'(\d+)').firstMatch(bitrate);
+  return match != null ? int.tryParse(match.group(1)!) : null;
+}

lib/utils/file_access.dart

@@ -229,6 +229,22 @@ bool isContentUri(String? path) {
   return path != null && path.startsWith('content://');
 }
 
+bool isSameContentUri(String? first, String? second) {
+  if (first == null || second == null) return false;
+  if (first == second) return true;
+  if (!isContentUri(first) || !isContentUri(second)) return false;
+
+  String decode(String value) {
+    try {
+      return Uri.decodeFull(value);
+    } catch (_) {
+      return value;
+    }
+  }
+
+  return decode(first) == decode(second);
+}
+
 /// Pattern matching CUE virtual path suffixes like #track01, #track12, etc.
 final _cueTrackSuffix = RegExp(r'#track\d+$');
 

lib/widgets/audio_analysis_widget.dart

@@ -15,10 +15,13 @@ import 'package:spotiflac_android/l10n/l10n.dart';
 import 'package:spotiflac_android/services/platform_bridge.dart';
 
 class AudioAnalysisData {
+  static const cacheVersion = 3;
+
   final String filePath;
   final int fileSize;
   final int sampleRate;
   final int channels;
+  final String channelLayout;
   final int bitsPerSample;
   final double duration;
   final int bitrate;
@@ -34,6 +37,7 @@ class AudioAnalysisData {
     required this.fileSize,
     required this.sampleRate,
     required this.channels,
+    this.channelLayout = '',
     required this.bitsPerSample,
     required this.duration,
     required this.bitrate,
@@ -47,9 +51,11 @@ class AudioAnalysisData {
 
   Map<String, dynamic> toJson() => {
     'filePath': filePath,
+    'cacheVersion': cacheVersion,
     'fileSize': fileSize,
     'sampleRate': sampleRate,
     'channels': channels,
+    'channelLayout': channelLayout,
     'bitsPerSample': bitsPerSample,
     'duration': duration,
     'bitrate': bitrate,
@@ -66,6 +72,7 @@ class AudioAnalysisData {
       fileSize: json['fileSize'] as int,
       sampleRate: json['sampleRate'] as int,
       channels: json['channels'] as int,
+      channelLayout: json['channelLayout']?.toString() ?? '',
       bitsPerSample: json['bitsPerSample'] as int,
       duration: (json['duration'] as num).toDouble(),
       bitrate: json['bitrate'] as int,
@@ -116,11 +123,20 @@ class _AudioAnalysisCardState extends State<AudioAnalysisCard> {
     '.flac',
     '.mp3',
     '.m4a',
+    '.mp4',
     '.aac',
+    '.ac3',
+    '.eac3',
     '.opus',
     '.ogg',
     '.wav',
     '.wma',
+    '.mka',
+    '.wv',
+    '.ape',
+    '.tta',
+    '.aif',
+    '.aiff',
   };
 
   bool get _isSupported {
@@ -268,11 +284,18 @@ class _AudioAnalysisCardState extends State<AudioAnalysisCard> {
       final json = Map<String, dynamic>.from(
         jsonDecode(await file.readAsString()) as Map,
       );
+      if (json['cacheVersion'] != AudioAnalysisData.cacheVersion) {
+        return null;
+      }
       final cachedSize = json['fileSize'] as int;
 
       if (!filePath.startsWith('content://')) {
         final currentSize = await File(filePath).length();
         if (currentSize != cachedSize) return null;
+      } else {
+        final stat = await PlatformBridge.safStat(filePath);
+        final currentSize = (stat['size'] as num?)?.toInt() ?? 0;
+        if (currentSize > 0 && currentSize != cachedSize) return null;
       }
 
       return AudioAnalysisData.fromJson(json);
@@ -348,7 +371,7 @@ class _AudioAnalysisCardState extends State<AudioAnalysisCard> {
         await _decodeToPCM(workingPath, pcmPath, info.sampleRate);
 
         final pcmBytes = await File(pcmPath).readAsBytes();
-        final result = await compute(
+        final spectrumResult = await compute(
           _analyzeInIsolate,
           _AnalysisParams(
             pcmBytes: pcmBytes,
@@ -356,26 +379,30 @@ class _AudioAnalysisCardState extends State<AudioAnalysisCard> {
             bitsPerSample: info.bitsPerSample,
           ),
         );
-
-        final trueTotalSamples =
-            (info.duration * info.sampleRate * info.channels).round();
+        final levelMetrics = await _runFullStreamLevelAnalysis(workingPath);
+        final peakAmplitude =
+            levelMetrics?.peakDb ?? spectrumResult.peakAmplitude;
+        final rmsLevel = levelMetrics?.rmsDb ?? spectrumResult.rmsLevel;
+        final dynamicRange =
+            levelMetrics?.dynamicRangeDb ?? (peakAmplitude - rmsLevel);
 
         return AudioAnalysisData(
           filePath: filePath,
           fileSize: info.fileSize,
           sampleRate: info.sampleRate,
           channels: info.channels,
+          channelLayout: info.channelLayout,
           bitsPerSample: info.bitsPerSample,
           duration: info.duration,
           bitrate: info.bitrate,
           bitDepth: info.bitsPerSample > 0
               ? '${info.bitsPerSample}-bit'
               : 'N/A',
-          dynamicRange: result.dynamicRange,
-          peakAmplitude: result.peakAmplitude,
-          rmsLevel: result.rmsLevel,
-          totalSamples: trueTotalSamples,
-          spectrum: result.spectrum,
+          dynamicRange: dynamicRange,
+          peakAmplitude: peakAmplitude,
+          rmsLevel: rmsLevel,
+          totalSamples: info.totalSamples,
+          spectrum: spectrumResult.spectrum,
         );
       } finally {
         try {
@@ -415,25 +442,38 @@ class _AudioAnalysisCardState extends State<AudioAnalysisCard> {
     final sampleRate =
         int.tryParse(props['sample_rate']?.toString() ?? '') ?? 0;
     final channels = int.tryParse(props['channels']?.toString() ?? '') ?? 0;
+    final channelLayout =
+        props['channel_layout']?.toString() ??
+        props['ch_layout']?.toString() ??
+        '';
+    final streamDuration = double.tryParse(props['duration']?.toString() ?? '');
+    final containerDuration = double.tryParse(info.getDuration() ?? '');
     final duration =
-        double.tryParse(
-          info.getDuration() ?? props['duration']?.toString() ?? '',
-        ) ??
+        (streamDuration != null && streamDuration > 0
+            ? streamDuration
+            : containerDuration) ??
         0;
+    final streamBitrate = int.tryParse(props['bit_rate']?.toString() ?? '');
+    final containerBitrate = int.tryParse(info.getBitrate() ?? '');
     final bitrate =
-        int.tryParse(
-          info.getBitrate() ?? props['bit_rate']?.toString() ?? '',
-        ) ??
-        0;
+        streamBitrate ??
+        containerBitrate ??
+        (duration > 0 && fileSize > 0 ? (fileSize * 8 / duration).round() : 0);
 
-    int bitsPerSample =
-        int.tryParse(props['bits_per_raw_sample']?.toString() ?? '') ?? 0;
-    if (bitsPerSample == 0) {
+    final codecName = props['codec_name']?.toString().toLowerCase() ?? '';
+    final canReportStoredBitDepth = _codecHasStoredBitDepth(codecName);
+
+    int bitsPerSample = 0;
+    if (canReportStoredBitDepth) {
       bitsPerSample =
-          int.tryParse(props['bits_per_sample']?.toString() ?? '') ?? 0;
+          int.tryParse(props['bits_per_raw_sample']?.toString() ?? '') ?? 0;
+      if (bitsPerSample == 0) {
+        bitsPerSample =
+            int.tryParse(props['bits_per_sample']?.toString() ?? '') ?? 0;
+      }
     }
 
-    if (bitsPerSample == 0) {
+    if (bitsPerSample == 0 && canReportStoredBitDepth) {
       final sampleFmt = props['sample_fmt']?.toString() ?? '';
       if (sampleFmt.contains('16') ||
           sampleFmt == 's16' ||
@@ -452,12 +492,117 @@ class _AudioAnalysisCardState extends State<AudioAnalysisCard> {
       fileSize: fileSize,
       sampleRate: sampleRate,
       channels: channels,
+      channelLayout: channelLayout,
       bitsPerSample: bitsPerSample,
       duration: duration,
       bitrate: bitrate,
+      totalSamples: _estimateTotalSamples(
+        props: props,
+        duration: duration,
+        sampleRate: sampleRate,
+        channels: channels,
+      ),
     );
   }
 
+  int _estimateTotalSamples({
+    required Map<dynamic, dynamic> props,
+    required double duration,
+    required int sampleRate,
+    required int channels,
+  }) {
+    final nbSamples = int.tryParse(props['nb_samples']?.toString() ?? '');
+    if (nbSamples != null && nbSamples > 0) {
+      return nbSamples;
+    }
+
+    final durationTs = int.tryParse(props['duration_ts']?.toString() ?? '');
+    final timeBase = props['time_base']?.toString() ?? '';
+    if (durationTs != null && durationTs > 0 && timeBase.contains('/')) {
+      final parts = timeBase.split('/');
+      final numerator = double.tryParse(parts[0]);
+      final denominator = double.tryParse(parts[1]);
+      if (numerator != null &&
+          numerator > 0 &&
+          denominator != null &&
+          denominator > 0 &&
+          sampleRate > 0) {
+        final seconds = durationTs * numerator / denominator;
+        return (seconds * sampleRate).round();
+      }
+    }
+
+    if (duration > 0 && sampleRate > 0) {
+      return (duration * sampleRate).round();
+    }
+    return 0;
+  }
+
+  bool _codecHasStoredBitDepth(String codecName) {
+    if (codecName.isEmpty) return false;
+    return codecName == 'flac' ||
+        codecName == 'alac' ||
+        codecName == 'wavpack' ||
+        codecName == 'ape' ||
+        codecName == 'tta' ||
+        codecName.startsWith('pcm_');
+  }
+
+  Future<_LevelMetrics?> _runFullStreamLevelAnalysis(String inputPath) async {
+    await FFmpegKitConfig.setLogLevel(Level.avLogInfo);
+    try {
+      final session = await FFmpegKit.executeWithArguments([
+        '-v',
+        'info',
+        '-hide_banner',
+        '-nostats',
+        '-i',
+        inputPath,
+        '-map',
+        '0:a:0',
+        '-af',
+        'astats=metadata=1:reset=0',
+        '-f',
+        'null',
+        '-',
+      ]);
+
+      final returnCode = await session.getReturnCode();
+      if (!ReturnCode.isSuccess(returnCode)) {
+        return null;
+      }
+
+      final logs = await session.getLogsAsString();
+      final overallMatch = RegExp(r'Overall([\s\S]*)').firstMatch(logs);
+      final section = overallMatch?.group(1) ?? logs;
+      final peak = _parseLastAstatsValue(section, 'Peak level dB');
+      final rms = _parseLastAstatsValue(section, 'RMS level dB');
+      if (peak == null || rms == null) return null;
+      return _LevelMetrics(
+        peakDb: peak,
+        rmsDb: rms,
+        dynamicRangeDb: _parseLastAstatsValue(section, 'Dynamic range'),
+      );
+    } finally {
+      await FFmpegKitConfig.setLogLevel(Level.avLogError);
+    }
+  }
+
+  double? _parseLastAstatsValue(String text, String label) {
+    final matches = RegExp(
+      '${RegExp.escape(label)}:\\s*([-+]?\\d+(?:\\.\\d+)?)',
+      caseSensitive: false,
+    ).allMatches(text);
+    double? value;
+    for (final match in matches) {
+      final parsed = double.tryParse(match.group(1) ?? '');
+      if (parsed != null && parsed.isFinite) {
+        value = parsed;
+      }
+    }
+    return value;
+  }
+
   Future<void> _decodeToPCM(
     String inputPath,
     String outputPath,
@@ -651,17 +796,33 @@ class _MediaInfo {
   final int fileSize;
   final int sampleRate;
   final int channels;
+  final String channelLayout;
   final int bitsPerSample;
   final double duration;
   final int bitrate;
+  final int totalSamples;
 
   const _MediaInfo({
     required this.fileSize,
     required this.sampleRate,
     required this.channels,
+    required this.channelLayout,
     required this.bitsPerSample,
     required this.duration,
     required this.bitrate,
+    required this.totalSamples,
+  });
+}
+
+class _LevelMetrics {
+  final double peakDb;
+  final double rmsDb;
+  final double? dynamicRangeDb;
+
+  const _LevelMetrics({
+    required this.peakDb,
+    required this.rmsDb,
+    this.dynamicRangeDb,
   });
 }
 
@@ -899,14 +1060,17 @@ class _AudioInfoCard extends StatelessWidget {
                   value: data.bitDepth,
                   cs: cs,
                 ),
+                if (data.bitrate > 0)
+                  _MetricChip(
+                    icon: Icons.speed,
+                    label: context.l10n.trackConvertBitrate,
+                    value: _formatBitrate(data.bitrate),
+                    cs: cs,
+                  ),
                 _MetricChip(
                   icon: Icons.surround_sound,
                   label: context.l10n.audioAnalysisChannels,
-                  value: data.channels == 2
-                      ? context.l10n.audioAnalysisStereo
-                      : data.channels == 1
-                      ? context.l10n.audioAnalysisMono
-                      : '${data.channels}',
+                  value: _formatChannels(context, data),
                   cs: cs,
                 ),
                 _MetricChip(
@@ -916,7 +1080,7 @@ class _AudioInfoCard extends StatelessWidget {
                   cs: cs,
                 ),
                 _MetricChip(
-                  icon: Icons.speed,
+                  icon: Icons.multiline_chart,
                   label: context.l10n.audioAnalysisNyquist,
                   value: '${(nyquist / 1000).toStringAsFixed(1)} kHz',
                   cs: cs,
@@ -975,6 +1139,16 @@ class _AudioInfoCard extends StatelessWidget {
     return '$mins:${secs.toString().padLeft(2, '0')}';
   }
 
+  String _formatChannels(BuildContext context, AudioAnalysisData data) {
+    final layout = data.channelLayout.trim();
+    if (layout.isNotEmpty && layout != 'unknown') {
+      return data.channels > 0 ? '${data.channels} ($layout)' : layout;
+    }
+    if (data.channels == 2) return context.l10n.audioAnalysisStereo;
+    if (data.channels == 1) return context.l10n.audioAnalysisMono;
+    return data.channels > 0 ? '${data.channels}' : 'N/A';
+  }
+
   String _formatFileSize(int bytes) {
     if (bytes == 0) return '0 B';
     const units = ['B', 'KB', 'MB', 'GB'];
@@ -983,6 +1157,13 @@ class _AudioInfoCard extends StatelessWidget {
     return '${size.toStringAsFixed(1)} ${units[i]}';
   }
 
+  String _formatBitrate(int bitsPerSecond) {
+    if (bitsPerSecond >= 1000000) {
+      return '${(bitsPerSecond / 1000000).toStringAsFixed(2)} Mbps';
+    }
+    return '${(bitsPerSecond / 1000).round()} kbps';
+  }
+
   String _formatNumber(int n) {
     if (n >= 1000000) return '${(n / 1000000).toStringAsFixed(1)}M';
     if (n >= 1000) return '${(n / 1000).toStringAsFixed(1)}K';