from contextlib import asynccontextmanager

from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware

from app.config import get_settings

settings = get_settings()


@asynccontextmanager
async def lifespan(app: FastAPI):
    # 启动时：确保数据目录存在
    settings.ensure_dirs()
    yield
    # 关闭时：清理资源（如有需要）


def create_app() -> FastAPI:
    app = FastAPI(
        title="PEFT Fine-Tuning Platform",
        version="0.1.0",
        lifespan=lifespan,
    )

    # CORS 中间件
    app.add_middleware(
        CORSMiddleware,
        allow_origins=settings.backend_cors_origins,
        allow_credentials=True,
        allow_methods=["*"],
        allow_headers=["*"],
    )

    # 挂载路由 (Phase 2 起逐步填充)
    from app.api import models as models_api
    from app.api import datasets as datasets_api
    from app.api import training as training_api
    from app.api import evaluation as evaluation_api
    from app.api import deployment as deployment_api

    app.include_router(models_api.router, prefix="/api/v1/models", tags=["models"])
    app.include_router(datasets_api.router, prefix="/api/v1/datasets", tags=["datasets"])
    app.include_router(training_api.router, prefix="/api/v1/training", tags=["training"])
    app.include_router(evaluation_api.router, prefix="/api/v1/evaluation", tags=["evaluation"])
    app.include_router(deployment_api.router, prefix="/api/v1/deployment", tags=["deployment"])

    # WebSocket
    from app.core.websocket import router as ws_router

    app.include_router(ws_router)

    @app.get("/health")
    async def health_check():
        return {"status": "ok", "env": settings.backend_env}

    return app


app = create_app()