"""
全局异常处理和错误响应
"""

import logging

from fastapi import Request, status
from fastapi.exceptions import RequestValidationError
from fastapi.responses import JSONResponse
from starlette.exceptions import HTTPException as StarletteHTTPException

logger = logging.getLogger(__name__)


class APIException(Exception):
    """API 异常基类"""

    def __init__(
        self,
        message: str,
        status_code: int = status.HTTP_400_BAD_REQUEST,
        error_code: str = "API_ERROR",
    ):
        self.message = message
        self.status_code = status_code
        self.error_code = error_code
        super().__init__(message)


class AuthenticationError(APIException):
    """认证错误"""

    def __init__(self, message: str = "Authentication failed"):
        super().__init__(
            message=message,
            status_code=status.HTTP_401_UNAUTHORIZED,
            error_code="AUTH_ERROR",
        )


class PermissionDeniedError(APIException):
    """权限拒绝"""

    def __init__(self, message: str = "Permission denied"):
        super().__init__(
            message=message,
            status_code=status.HTTP_403_FORBIDDEN,
            error_code="PERMISSION_DENIED",
        )


class ResourceNotFoundError(APIException):
    """资源不存在"""

    def __init__(self, resource: str = "Resource"):
        super().__init__(
            message=f"{resource} not found",
            status_code=status.HTTP_404_NOT_FOUND,
            error_code="NOT_FOUND",
        )


class ValidationError(APIException):
    """验证错误"""

    def __init__(self, message: str):
        super().__init__(
            message=message,
            status_code=status.HTTP_422_UNPROCESSABLE_ENTITY,
            error_code="VALIDATION_ERROR",
        )


async def api_exception_handler(request: Request, exc: APIException):
    """API 异常处理"""
    return JSONResponse(
        status_code=exc.status_code,
        content={
            "error": {
                "code": exc.error_code,
                "message": exc.message,
            }
        },
    )


async def http_exception_handler(request: Request, exc: StarletteHTTPException):
    """HTTP 异常处理"""
    return JSONResponse(
        status_code=exc.status_code,
        content={
            "error": {
                "code": f"HTTP_{exc.status_code}",
                "message": exc.detail,
            }
        },
    )


async def validation_exception_handler(request: Request, exc: RequestValidationError):
    """请求验证异常处理"""
    errors = []
    for error in exc.errors():
        errors.append(
            {
                "field": ".".join(str(loc) for loc in error["loc"]),
                "message": error["msg"],
                "type": error["type"],
            }
        )

    return JSONResponse(
        status_code=status.HTTP_422_UNPROCESSABLE_ENTITY,
        content={
            "error": {
                "code": "VALIDATION_ERROR",
                "message": "Request validation failed",
                "details": errors,
            }
        },
    )


async def general_exception_handler(request: Request, exc: Exception):
    """通用异常处理"""
    logger.error(f"Unhandled exception: {exc}", exc_info=True)

    # 生产环境不返回详细错误信息
    return JSONResponse(
        status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
        content={
            "error": {
                "code": "INTERNAL_ERROR",
                "message": "An internal error occurred",
                # "detail": str(exc),  # 仅在开发环境启用
            }
        },
    )