package com.example.cattletends.exception;

import com.example.cattletends.common.Result;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpStatus;
import org.springframework.validation.FieldError;
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;

import java.util.HashMap;
import java.util.Map;

/**
 * 全局异常处理器
 */
@RestControllerAdvice
public class GlobalExceptionHandler {

    private static final Logger logger = LoggerFactory.getLogger(GlobalExceptionHandler.class);

    /**
     * 处理参数校验异常
     */
    @ExceptionHandler(MethodArgumentNotValidException.class)
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    public Result<Map<String, String>> handleValidationExceptions(MethodArgumentNotValidException ex) {
        Map<String, String> errors = new HashMap<>();
        ex.getBindingResult().getAllErrors().forEach((error) -> {
            String fieldName = ((FieldError) error).getField();
            String errorMessage = error.getDefaultMessage();
            errors.put(fieldName, errorMessage);
        });
        logger.warn("参数校验失败: {}", errors);
        return Result.error(400, "参数校验失败", errors);
    }

    /**
     * 处理业务异常
     */
    @ExceptionHandler(RuntimeException.class)
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    public Result<Void> handleRuntimeException(RuntimeException ex) {
        logger.error("业务异常: {}", ex.getMessage(), ex);
        return Result.error(400, ex.getMessage());
    }

    /**
     * 处理非法参数异常
     */
    @ExceptionHandler(IllegalArgumentException.class)
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    public Result<Void> handleIllegalArgumentException(IllegalArgumentException ex) {
        logger.warn("非法参数: {}", ex.getMessage());
        return Result.error(400, ex.getMessage());
    }

    /**
     * 处理所有其他异常
     */
    @ExceptionHandler(Exception.class)
    @ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
    public Result<Void> handleException(Exception ex) {
        logger.error("系统异常: {}", ex.getMessage(), ex);
        return Result.error(500, "系统内部错误，请联系管理员");
    }
}