# backend.py
from contextlib import asynccontextmanager
from fastapi import FastAPI, HTTPException, Request, APIRouter
from pydantic import BaseModel
import asyncio

from starlette.middleware.cors import CORSMiddleware

from middlewares.handle import handle_middleware
from rag import rag_generate_rule
from util.log_util import logger


@asynccontextmanager
async def lifespan(app : FastAPI):
    # logger.info(f'{AppConfig.app_name}开始启动，当前运行环境{os.environ.get('APP_ENV', '未读取到环境变量APP_ENV')}')
    print(f'开始启动')
    yield
    print(f'关闭成功')

app = FastAPI(title="RAG SQL Generator API", description="调用RAG生成SQL语句的后端服务", lifespan=lifespan)

rule_router = APIRouter(prefix="/rule")

# 添加CORS中间件 - 允许所有来源（开发环境）
# app.add_middleware(
#     CORSMiddleware,
#     allow_origins=["*"],  # 在生产环境中应该指定具体的域名
#     allow_credentials=True,
#     allow_methods=["*"],
#     allow_headers=["*"],
# )

# 加载中间件
handle_middleware(app)








class QueryRequest(BaseModel):
    query: str

class QueryResponse(BaseModel):
    sql: str

@rule_router.post("/generate_sql", response_model=QueryResponse)
async def generate_sql(request: QueryRequest):
    """
    接收用户问题并调用RAG生成SQL语句

    - **query**: 用户的自然语言问题
    - 返回生成的SQL语句
    """
    try:
        # 调用rag_generate_rule方法生成SQL
        result = await rag_generate_rule(request.query)
        return QueryResponse(sql=result)
    except Exception as e:
        # print(e)
        # print(e.__context__)
        logger.info(e)
        logger.info(e.__context__)
        raise HTTPException(status_code=500, detail=f"生成SQL时出错: {str(e)}")

@rule_router.get("/health")
async def health_check():
    """
    健康检查端点
    """
    return {"status": "healthy"}


# 注册带前缀的路由器
app.include_router(rule_router)

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=8000)