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

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, log_pool_status, get_pool_status
from .api.account import router as account_router
from .api.database import router as database_router
from .api.task import router as task_router
from .api.comprehensive_data import router as comprehensive_data_router
from .api.export_excel import router as export_excel_router
from .api.daily import router as daily_router
from .api.section_data import router as section_data_router
from .api.level_data import router as level_data_router
from .api.checkpoint import router as checkpoint_router
from .api.function_list import router as function_list_router
from .utils.scheduler import task_scheduler

# 初始化日志系统
setup_logging()
logger = get_logger(__name__)

@asynccontextmanager
async def lifespan(app: FastAPI):
    """应用生命周期管理"""
    # 启动时执行
    logger.info("应用启动中...")

    # 初始化数据库
    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}")

    # 启动数据库监控
    try:
        start_monitoring()
        logger.info("数据库连接池监控已启动")

        # 记录初始连接池状态
        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}")

    # 启动定时任务调度器
    try:
        task_scheduler.start()
        logger.info("定时任务调度器启动完成")
    except Exception as e:
        logger.error(f"定时任务调度器启动失败: {e}")

    yield

    # 关闭时执行
    logger.info("应用关闭中...")

    # 记录最终连接池状态
    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}")

    try:
        task_scheduler.shutdown()
        logger.info("定时任务调度器已关闭")
    except Exception as e:
        logger.error(f"定时任务调度器关闭失败: {e}")

# 创建FastAPI应用
app = FastAPI(
    title="铁路项目管理系统",
    description="基于FastAPI、MySQL、SQLAlchemy的铁路项目管理系统",
    version="1.0.0",
    lifespan=lifespan
)

# 配置CORS
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # 生产环境建议配置具体域名
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# 注册路由
app.include_router(account_router, prefix="/api")
app.include_router(database_router, prefix="/api")
app.include_router(task_router, prefix="/api")
app.include_router(comprehensive_data_router, prefix="/api")
app.include_router(export_excel_router, prefix="/api")
app.include_router(daily_router, prefix="/api")
app.include_router(section_data_router, prefix="/api")
app.include_router(level_data_router, prefix="/api")
app.include_router(checkpoint_router, prefix="/api")
app.include_router(function_list_router, prefix="/api")
# app.include_router(test_router, prefix="/api")

# 根路径
@app.get("/")
async def root():
    """根路径"""
    return {
        "message": "铁路项目管理系统 API",
        "version": "1.0.0",
        "docs": "/docs",
        "redoc": "/redoc"
    }

# 健康检查
@app.get("/health")
async def health_check():
    """健康检查"""
    return {
        "status": "healthy",
        "database": "connected",
        "scheduler": "running" if task_scheduler.scheduler.running else "stopped"
    }

# 数据库监控端点
@app.get("/api/monitor/database")
async def get_database_monitor():
    """获取数据库连接池监控信息"""
    from .core.db_monitor import get_monitoring_report
    return get_monitoring_report()

# 连接池状态端点
@app.get("/api/monitor/pool")
async def get_pool_status():
    """获取连接池状态"""
    from .core.db_monitor import get_pool_status
    return get_pool_status()

# 全局异常处理
@app.exception_handler(Exception)
async def global_exception_handler(request, exc):
    """全局异常处理"""
    import traceback
    from .core.db_monitor import get_pool_status

    # 获取异常详情
    error_msg = str(exc)
    error_type = type(exc).__name__
    stack_trace = traceback.format_exc()

    # 获取当前连接池状态
    try:
        pool_stats = get_pool_status()
        pool_info = f", 连接池使用率: {pool_stats.get('usage_percent', 'N/A')}%"
    except:
        pool_info = ""

    # 记录详细错误日志
    logger.error(
        f"🚨 全局异常: {error_type}: {error_msg} "
        f"请求路径: {request.url.path}, 方法: {request.method}{pool_info}\n"
        f"堆栈跟踪:\n{stack_trace}"
    )

    return HTTPException(
        status_code=500,
        detail=f"服务器内部错误: {error_type}"
    )