fix: Map audio format names to user-friendly display names

- Add mapFormatToDisplayName function to convert container formats to display names
- Map 'MPEG' container format to 'MP3' for better user experience
- Map other common formats: WAVE->WAV, FLAC->FLAC, AAC->AAC, etc.
- Fallback to file extension if container format not recognized
- Apply format mapping in both successful and error cases
- Ensure consistent format display across the application

Now MP3 files will display as 'MP3' instead of 'MPEG' in the UI.

packages/backend/src/services/audioMetadataService.ts

@@ -15,6 +15,45 @@ export interface AudioMetadata {
 }
 
 export class AudioMetadataService {
+  /**
+   * Map container format to user-friendly format name
+   */
+  private mapFormatToDisplayName(container: string, fileName: string): string {
+    // Map common container formats to display names
+    const formatMap: { [key: string]: string } = {
+      'MPEG': 'MP3',
+      'mp3': 'MP3',
+      'WAVE': 'WAV',
+      'wav': 'WAV',
+      'FLAC': 'FLAC',
+      'flac': 'FLAC',
+      'AAC': 'AAC',
+      'aac': 'AAC',
+      'OGG': 'OGG',
+      'ogg': 'OGG',
+      'M4A': 'M4A',
+      'm4a': 'M4A',
+      'WMA': 'WMA',
+      'wma': 'WMA',
+      'OPUS': 'OPUS',
+      'opus': 'OPUS',
+    };
+
+    // Try to map the container format
+    if (formatMap[container]) {
+      return formatMap[container];
+    }
+
+    // Fallback to file extension if container format is not recognized
+    const extension = fileName.split('.').pop()?.toLowerCase();
+    if (extension && formatMap[extension]) {
+      return formatMap[extension];
+    }
+
+    // Return the original container format if no mapping found
+    return container.toUpperCase();
+  }
+
   /**
    * Extract metadata from audio file buffer
    */
@@ -32,7 +71,7 @@ export class AudioMetadataService {
         bitrate: metadata.format.bitrate,
         sampleRate: metadata.format.sampleRate,
         channels: metadata.format.numberOfChannels,
-        format: metadata.format.container,
+        format: this.mapFormatToDisplayName(metadata.format.container, fileName),
         size: fileBuffer.length,
       };
     } catch (error) {
@@ -41,7 +80,7 @@ export class AudioMetadataService {
       // Return basic metadata if extraction fails
       return {
         title: fileName.replace(/\.[^/.]+$/, ''), // Remove file extension
-        format: fileName.split('.').pop()?.toLowerCase(),
+        format: this.mapFormatToDisplayName(fileName.split('.').pop()?.toLowerCase() || '', fileName),
         size: fileBuffer.length,
       };
     }