Complete fix: Add ondemand mode model switching to audio and TTS endpoints

- Added model resolution and unload logic to /v1/audio/transcriptions
- Added model resolution and unload logic to /v1/audio/speech (TTS)
- Now ALL endpoints (text, image, audio, TTS) properly handle model switching
- In ondemand mode, ANY model type switch triggers unload first (e.g., text->audio, TTS->image, etc.)

codai/api/transcriptions.py

@@ -61,6 +61,40 @@ async def create_transcription(
             detail="Audio transcription not configured. Use --audio-model or --whisper-server."
         )
     
+    # Get load mode to determine if we need to unload other models first
+    from codai.api.state import get_load_mode
+    from codai.models.manager import model_manager
+    load_mode = get_load_mode()
+    
+    # In ondemand mode, if ANY model is loaded and it's different from what we need, unload first
+    if load_mode == "ondemand":
+        has_any_model = len(multi_model_manager.models) > 0 or model_manager.backend is not None
+        
+        if has_any_model:
+            # Resolve both the requested audio model and currently loaded model to their canonical names
+            requested_canonical = multi_model_manager.resolve_model_name(f"audio:{audio_model}")
+            loaded_canonical = multi_model_manager.get_currently_loaded_model_name()
+            
+            # Also check legacy model_manager
+            if not loaded_canonical and model_manager.backend is not None:
+                loaded_canonical = "legacy_model_manager"
+            
+            # Compare: if they're different models, unload first
+            already_loaded = (requested_canonical and loaded_canonical and 
+                            requested_canonical == loaded_canonical)
+            
+            if not already_loaded:
+                print(f"In ondemand mode - model switch detected:")
+                print(f"  Requested: 'audio:{audio_model}' (resolved to: '{requested_canonical}')")
+                print(f"  Loaded: '{loaded_canonical}'")
+                print(f"  -> Fully unloading current model(s) before loading audio model...")
+                multi_model_manager.unload_all_models()
+                if model_manager.backend is not None:
+                    try:
+                        model_manager.cleanup()
+                    except:
+                        pass
+    
     # Determine model to use
     model_to_use = model
     if model_to_use.startswith("whisper:") or model_to_use.startswith("audio:"):

codai/api/tts.py

@@ -74,6 +74,40 @@ async def create_speech(request: TTSRequest):
             detail="TTS not configured. Use --tts-model to specify a model."
         )
     
+    # Get load mode to determine if we need to unload other models first
+    from codai.api.state import get_load_mode
+    from codai.models.manager import model_manager
+    load_mode = get_load_mode()
+    
+    # In ondemand mode, if ANY model is loaded and it's different from what we need, unload first
+    if load_mode == "ondemand":
+        has_any_model = len(multi_model_manager.models) > 0 or model_manager.backend is not None
+        
+        if has_any_model:
+            # Resolve both the requested TTS model and currently loaded model to their canonical names
+            requested_canonical = multi_model_manager.resolve_model_name(f"tts:{tts_model}")
+            loaded_canonical = multi_model_manager.get_currently_loaded_model_name()
+            
+            # Also check legacy model_manager
+            if not loaded_canonical and model_manager.backend is not None:
+                loaded_canonical = "legacy_model_manager"
+            
+            # Compare: if they're different models, unload first
+            already_loaded = (requested_canonical and loaded_canonical and 
+                            requested_canonical == loaded_canonical)
+            
+            if not already_loaded:
+                print(f"In ondemand mode - model switch detected:")
+                print(f"  Requested: 'tts:{tts_model}' (resolved to: '{requested_canonical}')")
+                print(f"  Loaded: '{loaded_canonical}'")
+                print(f"  -> Fully unloading current model(s) before loading TTS model...")
+                multi_model_manager.unload_all_models()
+                if model_manager.backend is not None:
+                    try:
+                        model_manager.cleanup()
+                    except:
+                        pass
+    
     # Determine model to use
     model_to_use = request.model
     if model_to_use.startswith("tts:"):