fix(generation): block tasks without ready videos

apps/api/app/api/routes/generation_tasks.py

@@ -5,6 +5,7 @@ from app.api.routes.permissions import require_workspace_member
 from app.core.celery_app import celery_app
 from app.dependencies import (
     get_asset_library_repository,
+    get_asset_repository,
     get_generated_video_repository,
     get_generation_task_repository,
     get_project_repository,
@@ -63,6 +64,18 @@ def _to_generated_video_response(item) -> GeneratedVideoResponse:
     )
 
 
+def _ensure_library_has_ready_video_assets(assets) -> None:
+    ready_video_assets = [
+        asset for asset in assets
+        if asset.status.value == "ready" and asset.mime_type.startswith("video")
+    ]
+    if not ready_video_assets:
+        raise HTTPException(
+            status_code=422,
+            detail="当前素材库没有 ready 状态的视频素材，请先上传并等待导入完成后再生成。",
+        )
+
+
 @router.post("/tasks", response_model=GenerationTaskResponse)
 def create_generation_task(
     request: CreateGenerationTaskRequest,
@@ -70,6 +83,7 @@ def create_generation_task(
     generation_task_repository: Any = Depends(get_generation_task_repository),
     project_repository: Any = Depends(get_project_repository),
     asset_library_repository: Any = Depends(get_asset_library_repository),
+    asset_repository: Any = Depends(get_asset_repository),
     workspace_member_repository: WorkspaceMemberRepository = Depends(get_workspace_member_repository),
 ) -> GenerationTaskResponse:
     require_workspace_member(request.workspace_id, authenticated_user, workspace_member_repository)
@@ -79,6 +93,8 @@ def create_generation_task(
     library = asset_library_repository.get(request.asset_library_id)
     if library is None or library.workspace_id != request.workspace_id or library.project_id != request.project_id:
         raise HTTPException(status_code=404, detail=f"AssetLibrary {request.asset_library_id} not found")
+    assets = asset_repository.list_by_library(request.asset_library_id)
+    _ensure_library_has_ready_video_assets(assets)
 
     use_case = CreateGenerationTaskUseCase(generation_task_repository)
     task = use_case.execute(