from fastapi import FastAPI, Request
from fastapi.middleware.cors import CORSMiddleware
from contextlib import asynccontextmanager
import time

from .core.config import settings
from .core.logging_config import setup_logging, get_logger
from .core.database import init_db
from .core.db_monitor import start_monitoring, get_pool_status
from .api.work_area import router as work_area_router
from .api.section_data import router as section_data_router
from .api.checkpoint import router as checkpoint_router
from .api.measurement_data import router as measurement_data_router

# 初始化日志系统
setup_logging()
logger = get_logger(__name__)
access_logger = get_logger("uvicorn.access")

@asynccontextmanager
async def lifespan(app: FastAPI):
    """应用生命周期管理"""
    logger.info("应用启动中...")
    
    try:
        init_db()
        logger.info("数据库初始化完成")
    except Exception as e:
        logger.error(f"数据库初始化失败: {e}")
    
    try:
        start_monitoring()
        logger.info("数据库连接池监控已启动")
        pool_stats = get_pool_status()
        logger.info(f"初始连接池状态: {pool_stats}")
    except Exception as e:
        logger.error(f"数据库监控启动失败: {e}")
    
    yield
    
    logger.info("应用关闭中...")
    try:
        pool_stats = get_pool_status()
        logger.info(f"最终连接池状态: {pool_stats}")
    except Exception as e:
        logger.error(f"获取最终连接池状态失败: {e}")

# 创建FastAPI应用
app = FastAPI(
    title="工程围岩数据信息处理系统",
    description="基于FastAPI、MySQL、SQLAlchemy的工程围岩数据信息处理系统",
    version="1.0.0",
    lifespan=lifespan
)

# 配置CORS
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# 访问日志中间件
@app.middleware("http")
async def log_requests(request: Request, call_next):
    start_time = time.time()
    response = await call_next(request)
    process_time = time.time() - start_time
    access_logger.info(
        f"{request.method} {request.url.path} - {response.status_code} - {process_time:.3f}s"
    )
    return response

# 注册路由
app.include_router(work_area_router, prefix="/api")
app.include_router(section_data_router, prefix="/api")
app.include_router(checkpoint_router, prefix="/api")
app.include_router(measurement_data_router, prefix="/api")

@app.get("/")
async def root():
    """根路径"""
    return {
        "message": "工程围岩数据信息处理系统 API",
        "version": "1.0.0",
        "docs": "/docs"
    }

@app.get("/health")
async def health_check():
    """健康检查"""
    return {"status": "healthy", "database": "connected"}

@app.get("/api/monitor/pool")
async def get_pool_monitor():
    """获取连接池状态"""
    return get_pool_status()

@app.exception_handler(Exception)
async def global_exception_handler(request: Request, exc: Exception):
    """全局异常处理"""
    import traceback
    logger.error(f"全局异常: {type(exc).__name__}: {exc}\n{traceback.format_exc()}")
    return {"detail": f"服务器内部错误: {type(exc).__name__}", "status_code": 500}