feat: Add voice design support for voice cloning and enhance cache management

qwen3-tts-backend/api/voice_designs.py

@@ -1,13 +1,14 @@
 import logging
-from fastapi import APIRouter, Depends, HTTPException, status, Request
+from fastapi import APIRouter, Depends, HTTPException, status, Request, BackgroundTasks
 from sqlalchemy.orm import Session
 from typing import Optional
 from slowapi import Limiter
 from slowapi.util import get_remote_address
+from pathlib import Path
 
 from core.database import get_db
 from api.auth import get_current_user
-from db.models import User
+from db.models import User, Job, JobStatus
 from db import crud
 from schemas.voice_design import (
     VoiceDesignCreate,
@@ -95,3 +96,116 @@ async def delete_voice_design(
     success = crud.delete_voice_design(db, design_id, current_user.id)
     if not success:
         raise HTTPException(status_code=404, detail="Voice design not found")
+
+@router.post("/{design_id}/prepare-clone")
+@limiter.limit("10/minute")
+async def prepare_voice_clone_prompt(
+    request: Request,
+    design_id: int,
+    background_tasks: BackgroundTasks,
+    current_user: User = Depends(get_current_user),
+    db: Session = Depends(get_db)
+):
+    from core.tts_service import TTSServiceFactory
+    from core.cache_manager import VoiceCacheManager
+    from utils.audio import process_ref_audio, extract_audio_features
+    from core.config import settings
+    from db.crud import can_user_use_local_model
+    from datetime import datetime
+
+    design = crud.get_voice_design(db, design_id, current_user.id)
+    if not design:
+        raise HTTPException(status_code=404, detail="Voice design not found")
+
+    if design.backend_type != "local":
+        raise HTTPException(
+            status_code=400,
+            detail="Voice clone prompt preparation is only supported for local backend"
+        )
+
+    if not can_user_use_local_model(current_user):
+        raise HTTPException(
+            status_code=403,
+            detail="Local model access required"
+        )
+
+    if design.voice_cache_id:
+        return {
+            "message": "Voice clone prompt already exists",
+            "cache_id": design.voice_cache_id
+        }
+
+    try:
+        backend = await TTSServiceFactory.get_backend("local")
+
+        ref_text = design.preview_text or design.instruct[:100]
+
+        logger.info(f"Generating reference audio for voice design {design_id}")
+        ref_audio_bytes, sample_rate = await backend.generate_voice_design({
+            "text": ref_text,
+            "language": "Auto",
+            "instruct": design.instruct,
+            "max_new_tokens": 2048,
+            "temperature": 0.3,
+            "top_k": 10,
+            "top_p": 0.5,
+            "repetition_penalty": 1.05
+        })
+
+        timestamp = datetime.utcnow().strftime("%Y%m%d_%H%M%S")
+        ref_filename = f"voice_design_{design_id}_{timestamp}.wav"
+        ref_audio_path = Path(settings.OUTPUT_DIR) / ref_filename
+
+        with open(ref_audio_path, 'wb') as f:
+            f.write(ref_audio_bytes)
+
+        logger.info(f"Extracting voice clone prompt from reference audio")
+        ref_audio_array, ref_sr = process_ref_audio(ref_audio_bytes)
+
+        from core.model_manager import ModelManager
+        model_manager = await ModelManager.get_instance()
+        await model_manager.load_model("base")
+        _, tts = await model_manager.get_current_model()
+
+        if tts is None:
+            raise RuntimeError("Failed to load base model")
+
+        x_vector = tts.create_voice_clone_prompt(
+            ref_audio=(ref_audio_array, ref_sr),
+            ref_text=ref_text,
+            x_vector_only_mode=True
+        )
+
+        cache_manager = await VoiceCacheManager.get_instance()
+        ref_audio_hash = cache_manager.get_audio_hash(ref_audio_bytes)
+
+        features = extract_audio_features(ref_audio_array, ref_sr)
+        metadata = {
+            'duration': features['duration'],
+            'sample_rate': features['sample_rate'],
+            'ref_text': ref_text,
+            'x_vector_only_mode': True,
+            'voice_design_id': design_id,
+            'instruct': design.instruct
+        }
+
+        cache_id = await cache_manager.set_cache(
+            current_user.id, ref_audio_hash, x_vector, metadata, db
+        )
+
+        design.voice_cache_id = cache_id
+        design.ref_audio_path = str(ref_audio_path)
+        design.ref_text = ref_text
+        db.commit()
+
+        logger.info(f"Voice clone prompt prepared for design {design_id}, cache_id={cache_id}")
+
+        return {
+            "message": "Voice clone prompt prepared successfully",
+            "cache_id": cache_id,
+            "ref_text": ref_text
+        }
+
+    except Exception as e:
+        logger.error(f"Failed to prepare voice clone prompt: {e}", exc_info=True)
+        raise HTTPException(status_code=500, detail=str(e))