fix: ensure MP3 to WAV conversion creates file

- Add proper error handling around pydub conversion
- Use absolute paths instead of relative paths
- Ensure output directory exists before saving
- Verify file was actually created before returning
- Add fallback to MP3 if conversion fails
- Update tts.py to handle both .wav and .mp3 extensions
- Add detailed logging for debugging

app/api/tts.py

@@ -121,16 +121,28 @@ class TTS(Resource):
             seed_vc_model = current_app.config['SEED_VC_MODEL']
             seed_vc_repo = current_app.config['SEED_VC_REPO_PATH']
             vc_service = SeedVCService(model_name=seed_vc_model, repo_path=seed_vc_repo)
-            vc_service.convert_voice(tts_output, reference_path, final_output)
+            actual_output = vc_service.convert_voice(tts_output, reference_path, final_output)
             
-            logger.info(f"TTS+VC complete: {final_output}")
+            # Verify the output file exists
+            if not os.path.exists(actual_output):
+                raise FileNotFoundError(f"Output file was not created: {actual_output}")
+            
+            # Determine mimetype and download name based on actual output
+            if actual_output.endswith('.mp3'):
+                mimetype = 'audio/mpeg'
+                download_name = f"tts_{voice_id}.mp3"
+            else:
+                mimetype = 'audio/wav'
+                download_name = f"tts_{voice_id}.wav"
+            
+            logger.info(f"TTS+VC complete: {actual_output} ({os.path.getsize(actual_output)} bytes)")
             
             # Return audio file
             return send_file(
-                final_output,
-                mimetype='audio/wav',
+                actual_output,
+                mimetype=mimetype,
                 as_attachment=True,
-                download_name=f"tts_{voice_id}.wav"
+                download_name=download_name
             )
             
         except Exception as e: