package com.aijiuyi.admin.common;

import org.springframework.http.HttpStatus;
import org.springframework.security.access.AccessDeniedException;
import org.springframework.security.authentication.BadCredentialsException;
import org.springframework.validation.BindException;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseStatus;
import org.springframework.web.bind.annotation.RestControllerAdvice;

/**
 * 全局异常处理：业务异常、参数校验、认证与通用异常的统一 JSON 响应。
 */
@RestControllerAdvice
public class GlobalExceptionHandler {

    @ExceptionHandler(BusinessException.class)
    @ResponseStatus(HttpStatus.OK)
    public ApiResponse<Void> handleBusiness(BusinessException e) {
        return ApiResponse.fail(e.getCode(), e.getMessage());
    }

    @ExceptionHandler({MethodArgumentNotValidException.class, BindException.class})
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    public ApiResponse<Void> handleValidation(Exception e) {
        String msg = e.getMessage();
        if (e instanceof MethodArgumentNotValidException) {
            MethodArgumentNotValidException ex = (MethodArgumentNotValidException) e;
            if (ex.getBindingResult().getFieldError() != null) {
                msg = ex.getBindingResult().getFieldError().getDefaultMessage();
            }
        }
        return ApiResponse.fail(400, msg);
    }

    @ExceptionHandler(BadCredentialsException.class)
    @ResponseStatus(HttpStatus.UNAUTHORIZED)
    public ApiResponse<Void> handleBadCredentials(BadCredentialsException e) {
        return ApiResponse.fail(401, "用户名或密码错误");
    }

    @ExceptionHandler(AccessDeniedException.class)
    @ResponseStatus(HttpStatus.FORBIDDEN)
    public ApiResponse<Void> handleDenied(AccessDeniedException e) {
        return ApiResponse.fail(403, "无权限");
    }

    @ExceptionHandler(Exception.class)
    @ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
    public ApiResponse<Void> handleOther(Exception e) {
        return ApiResponse.fail(500, e.getMessage() != null ? e.getMessage() : "服务器错误");
    }
}