feat: Implement AI script generation for audiobook projects

qwen3-tts-backend/api/audiobook.py

@@ -23,6 +23,7 @@ from schemas.audiobook import (
     AudiobookSegmentUpdate,
     AudiobookGenerateRequest,
     AudiobookAnalyzeRequest,
+    ScriptGenerationRequest,
 )
 from core.config import settings
 
@@ -39,6 +40,7 @@ def _project_to_response(project) -> AudiobookProjectResponse:
         status=project.status,
         llm_model=project.llm_model,
         error_message=project.error_message,
+        script_config=getattr(project, 'script_config', None),
         created_at=project.created_at,
         updated_at=project.updated_at,
     )
@@ -150,6 +152,42 @@ async def list_projects(
     return [_project_to_response(p) for p in projects]
 
 
+@router.post("/projects/generate-script", response_model=AudiobookProjectResponse, status_code=status.HTTP_201_CREATED)
+async def create_ai_script_project(
+    data: ScriptGenerationRequest,
+    current_user: User = Depends(get_current_user),
+    db: Session = Depends(get_db),
+):
+    from db.crud import get_system_setting
+    if not get_system_setting(db, "llm_api_key") or not get_system_setting(db, "llm_base_url") or not get_system_setting(db, "llm_model"):
+        raise HTTPException(status_code=400, detail="LLM config not set. Please configure LLM API key first.")
+
+    project = crud.create_audiobook_project(
+        db=db,
+        user_id=current_user.id,
+        title=data.title,
+        source_type="ai_generated",
+        script_config=data.model_dump(),
+    )
+
+    from core.audiobook_service import generate_ai_script
+    from core.database import SessionLocal
+
+    project_id = project.id
+    user_id = current_user.id
+
+    async def run():
+        async_db = SessionLocal()
+        try:
+            db_user = crud.get_user_by_id(async_db, user_id)
+            await generate_ai_script(project_id, db_user, async_db)
+        finally:
+            async_db.close()
+
+    asyncio.create_task(run())
+    return _project_to_response(project)
+
+
 @router.get("/projects/{project_id}", response_model=AudiobookProjectDetail)
 async def get_project(
     project_id: int,
@@ -207,6 +245,23 @@ async def confirm_characters(
     if project.status != "characters_ready":
         raise HTTPException(status_code=400, detail="Project must be in 'characters_ready' state to confirm characters")
 
+    if project.source_type == "ai_generated":
+        from core.audiobook_service import generate_ai_script_chapters
+        from core.database import SessionLocal
+
+        user_id = current_user.id
+
+        async def run():
+            async_db = SessionLocal()
+            try:
+                db_user = crud.get_user_by_id(async_db, user_id)
+                await generate_ai_script_chapters(project_id, db_user, async_db)
+            finally:
+                async_db.close()
+
+        asyncio.create_task(run())
+        return {"message": "Script generation started", "project_id": project_id}
+
     from core.audiobook_service import identify_chapters
     try:
         identify_chapters(project_id, db, project)