package com.xuqm.update.controller;

import com.xuqm.common.exception.BusinessException;
import com.xuqm.common.model.ApiResponse;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.http.converter.HttpMessageNotReadableException;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;

import java.util.stream.Collectors;

@RestControllerAdvice
public class GlobalExceptionHandler {

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

    @ExceptionHandler(BusinessException.class)
    public ResponseEntity<ApiResponse<Void>> handle(BusinessException ex) {
        return ResponseEntity.status(resolveStatus(ex.getCode()))
                .body(ApiResponse.error(ex.getCode(), ex.getMessage()));
    }

    @ExceptionHandler(MethodArgumentNotValidException.class)
    public ResponseEntity<ApiResponse<Void>> handle(MethodArgumentNotValidException ex) {
        String message = ex.getBindingResult().getFieldErrors().stream()
                .map(f -> f.getDefaultMessage())
                .collect(Collectors.joining("; "));
        return ResponseEntity.badRequest().body(ApiResponse.badRequest(message));
    }

    @ExceptionHandler(IllegalArgumentException.class)
    public ResponseEntity<ApiResponse<Void>> handle(IllegalArgumentException ex) {
        return ResponseEntity.badRequest()
                .body(ApiResponse.badRequest(ex.getMessage() == null ? "参数错误" : ex.getMessage()));
    }

    @ExceptionHandler(HttpMessageNotReadableException.class)
    public ResponseEntity<ApiResponse<Void>> handle(HttpMessageNotReadableException ex) {
        return ResponseEntity.badRequest().body(ApiResponse.badRequest("请求体格式错误"));
    }

    @ExceptionHandler(Exception.class)
    public ResponseEntity<ApiResponse<Void>> handle(Exception ex) {
        log.error("Unhandled exception", ex);
        String detail = ex.getClass().getSimpleName() + ": " + ex.getMessage();
        Throwable cause = ex.getCause();
        if (cause != null) {
            detail += " | caused by: " + cause.getClass().getSimpleName() + ": " + cause.getMessage();
        }
        return ResponseEntity.internalServerError()
                .body(ApiResponse.error(500, detail));
    }

    private HttpStatus resolveStatus(int code) {
        return switch (code) {
            case 400 -> HttpStatus.BAD_REQUEST;
            case 401 -> HttpStatus.UNAUTHORIZED;
            case 403 -> HttpStatus.FORBIDDEN;
            case 404 -> HttpStatus.NOT_FOUND;
            default -> HttpStatus.INTERNAL_SERVER_ERROR;
        };
    }
}