from fastapi import FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse
import uvicorn
import logging
from contextlib import asynccontextmanager

# 导入路由模块
from api.v1.routes.database import router as database_router
from api.v1.routes.tables import router as tables_router
from database_manager import db_manager
from sample_data import SampleDataInitializer

# 配置日志
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s'
)
logger = logging.getLogger(__name__)

# 应用生命周期管理
@asynccontextmanager
async def lifespan(app: FastAPI):
    """应用启动和关闭时的处理"""
    # 启动时
    logger.info("数据库接口服务启动中...")
    
    # 初始化示例数据
    try:
        logger.info("开始初始化示例数据...")
        sample_initializer = SampleDataInitializer()
        sample_initializer.initialize_all_sample_data()
        logger.info("示例数据初始化完成")
    except Exception as e:
        logger.warning(f"示例数据初始化失败: {str(e)}")
        logger.info("服务将继续启动，但示例数据不可用")
    
    yield
    # 关闭时
    logger.info("数据库接口服务关闭中...")
    # 关闭所有数据库连接
    for connection_id in db_manager.list_connections():
        db_manager.close_connection(connection_id)
    logger.info("所有数据库连接已关闭")

# 创建FastAPI应用
app = FastAPI(
    title="数据库接口服务",
    description="提供统一的数据库管理接口，支持MySQL、Oracle、SQL Server、PostgreSQL等多种数据库类型",
    version="1.0.0",
    docs_url="/docs",
    redoc_url="/redoc",
    lifespan=lifespan
)

# 添加CORS中间件
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # 在生产环境中应该设置具体的域名
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# 全局异常处理
@app.exception_handler(Exception)
async def global_exception_handler(request, exc):
    """全局异常处理器"""
    logger.error(f"全局异常: {str(exc)}")
    return JSONResponse(
        status_code=500,
        content={
            "success": False,
            "message": "服务器内部错误",
            "error": str(exc)
        }
    )


# 健康检查接口
@app.get("/health", tags=["系统"])
async def health_check():
    """健康检查接口"""
    return {
        "success": True,
        "message": "服务运行正常",
        "data": {
            "status": "healthy",
            "active_connections": len(db_manager.list_connections())
        }
    }


# 根路径接口
@app.get("/", tags=["系统"])
async def root():
    """根路径接口"""
    return {
        "success": True,
        "message": "欢迎使用数据库接口服务",
        "data": {
            "title": "数据库接口服务",
            "version": "1.0.0",
            "description": "提供统一的数据库管理接口，支持MySQL、Oracle、SQL Server、PostgreSQL等多种数据库类型",
            "docs_url": "/docs",
            "redoc_url": "/redoc"
        }
    }

# 注册路由
app.include_router(database_router, prefix="/api/v1", tags=["数据库管理"])
app.include_router(tables_router, prefix="/api/v1", tags=["表管理"])

# 主函数
if __name__ == "__main__":
    logger.info("启动数据库接口服务...")
    uvicorn.run(
        "main:app",
        host="0.0.0.0",
        port=8000,
        log_level="info"
    )