"""FastAPI应用工厂"""
from contextlib import asynccontextmanager
from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware

from alcor.config import config
from alcor.database import init_db
from alcor.routes import api_router


@asynccontextmanager
async def lifespan(app: FastAPI):
    """应用生命周期管理"""
    # 启动时
    print("🚀 Starting up ChatBackend API...")
    
    # 初始化数据库
    init_db()
    print("✅ Database initialized")
    
    # 加载内置工具
    from alcor.tools.builtin import crawler, code, data
    print(f"✅ Loaded {len(api_router.routes)} API routes")
    
    yield
    
    # 关闭时
    print("👋 Shutting down ChatBackend API...")


def create_app() -> FastAPI:
    """创建FastAPI应用"""
    app = FastAPI(
        title="ChatBackend API",
        description="智能聊天后端API，支持多模型、流式响应、工具调用",
        version="1.0.0",
        lifespan=lifespan
    )
    
    # 配置CORS
    app.add_middleware(
        CORSMiddleware,
        allow_origins=["*"],  # 生产环境应限制
        allow_credentials=True,
        allow_methods=["*"],
        allow_headers=["*"],
    )
    
    # 注册路由
    app.include_router(api_router, prefix="/api")
    
    # 健康检查
    @app.get("/health")
    async def health_check():
        return {"status": "healthy", "service": "chat-backend"}
    
    @app.get("/")
    async def root():
        return {
            "service": "ChatBackend API",
            "version": "1.0.0",
            "docs": "/docs"
        }
    
    return app


# 创建应用实例
app = create_app()