# ===========================================
# 班级操行分管理系统 - 主入口
# 
# 开发者: Canglan
# 联系方式: admin@sea-studio.top
# 版权归属: Sea Network Technology Studio
# 许可证: MIT License
# 
# 版权所有 © Sea Network Technology Studio
# ===========================================

from fastapi import FastAPI, Request
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse
from contextlib import asynccontextmanager
import traceback
import uvicorn

from config import settings
from utils.logger import setup_logger, log_access
from utils.database import init_db_pool, close_db_pool
from utils.redis_client import init_redis_pool, close_redis_pool
from middleware.auth_middleware import AuthMiddleware
from routes import auth, student, parent, admin, subject, semester, debug


# 设置日志
logger = setup_logger()


@asynccontextmanager
async def lifespan(app: FastAPI):
    """应用生命周期管理"""
    logger.info("正在启动应用...")
    await init_db_pool()
    await init_redis_pool()
    logger.info(f"CORS 允许域名: {settings.CORS_ORIGINS}")
    logger.info(f"{settings.APP_NAME} 启动完成")
    
    yield
    
    logger.info("正在关闭应用...")
    await close_db_pool()
    await close_redis_pool()
    logger.info("应用已关闭")


# 创建FastAPI应用
app = FastAPI(
    title=settings.APP_NAME,
    version=settings.API_VERSION,
    debug=settings.DEBUG,
    lifespan=lifespan
)


# 访问日志中间件
@app.middleware("http")
async def access_log_middleware(request: Request, call_next):
    log_access(request)
    response = await call_next(request)
    return response


# 认证中间件（先注册，后执行）
app.add_middleware(AuthMiddleware)

# CORS中间件（后注册，先执行）- 从环境变量读取允许的域名
cors_origins = settings.CORS_ORIGINS
if not cors_origins:
    logger.warning("CORS_ORIGINS 未配置或为空，跨域请求将被拒绝！请检查 .env 文件中的 CORS_ORIGINS 配置")

app.add_middleware(
    CORSMiddleware,
    allow_origins=cors_origins,
    allow_credentials=True,
    allow_methods=["GET", "POST", "PUT", "DELETE", "OPTIONS"],
    allow_headers=["*"],
    expose_headers=["*"],
)


# 全局异常处理器
@app.exception_handler(Exception)
async def global_exception_handler(request: Request, exc: Exception):
    """全局异常处理器 - 捕获所有未处理异常"""
    logger.error(f"未处理异常: {exc}", exc_info=True)
    
    # 获取origin用于CORS头
    origin = request.headers.get("origin", "")
    allowed_origins = settings.CORS_ORIGINS or []
    
    # 使用HTTP 200 + 业务错误码返回，避免CORS头丢失问题
    # （FastAPI exception_handler返回的500响应可能不经过CORS中间件，导致跨域读取失败）
    headers = {}
    if origin in allowed_origins:
        headers["access-control-allow-origin"] = origin
        headers["access-control-allow-credentials"] = "true"
        headers["access-control-expose-headers"] = "*"
    
    return JSONResponse(
        status_code=200,
        content={
            "success": False,
            "code": 500,
            "message": f"服务器内部错误: {str(exc)}",
            "detail": traceback.format_exc() if settings.DEBUG else None
        },
        headers=headers
    )


# 注册路由
app.include_router(auth.router, prefix="/api/auth", tags=["认证"])
app.include_router(student.router, prefix="/api/student", tags=["学生端"])
app.include_router(parent.router, prefix="/api/parent", tags=["家长端"])
app.include_router(admin.router, prefix="/api/admin", tags=["管理端"])
app.include_router(subject.router, prefix="/api/subject", tags=["科目管理"])
app.include_router(semester.router, prefix="/api/semester", tags=["学期管理"])
app.include_router(debug.router, tags=["调试"])


@app.get("/")
async def root():
    return {"status": "ok", "message": f"{settings.APP_NAME} API 运行中"}


@app.get("/health")
async def health_check():
    return {"status": "healthy"}


if __name__ == "__main__":
    uvicorn.run(
        "main:app",
        host="0.0.0.0",
        port=8000,
        reload=settings.DEBUG
    )