package com.xuqm.bugcollect.controller;

import com.xuqm.common.exception.BusinessException;
import com.xuqm.common.model.ApiResponse;
import com.xuqm.bugcollect.service.BugCollectDisabledException;
import jakarta.servlet.http.HttpServletRequest;
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.validation.FieldError;
import org.springframework.web.HttpRequestMethodNotSupportedException;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.MissingServletRequestParameterException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;
import org.springframework.web.multipart.MaxUploadSizeExceededException;

import java.util.stream.Collectors;

@RestControllerAdvice
public class GlobalExceptionHandler {

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

    @ExceptionHandler(BugCollectDisabledException.class)
    public ResponseEntity<ApiResponse<Void>> handle(BugCollectDisabledException ex) {
        return ResponseEntity.status(HttpStatus.FORBIDDEN)
                .body(ApiResponse.error(403, BugCollectDisabledException.ERROR_CODE));
    }

    @ExceptionHandler(BusinessException.class)
    public ResponseEntity<ApiResponse<Void>> handle(BusinessException ex, HttpServletRequest request) {
        if (ex.getCode() >= 500) {
            log.error("[{}] {} code={} msg={}", request.getMethod(), request.getRequestURI(), ex.getCode(), ex.getMessage(), ex);
        } else {
            log.warn("[{}] {} code={} msg={}", request.getMethod(), request.getRequestURI(), ex.getCode(), ex.getMessage());
        }
        return ResponseEntity.status(resolveStatus(ex.getCode()))
                .body(ApiResponse.error(ex.getCode(), ex.getMessage()));
    }

    @ExceptionHandler(MethodArgumentNotValidException.class)
    public ResponseEntity<ApiResponse<Void>> handle(MethodArgumentNotValidException ex, HttpServletRequest request) {
        String message = ex.getBindingResult().getFieldErrors().stream()
                .map(FieldError::getDefaultMessage)
                .collect(Collectors.joining("; "));
        log.warn("[{}] {} validation failed: {}", request.getMethod(), request.getRequestURI(), message);
        return ResponseEntity.badRequest().body(ApiResponse.badRequest(message));
    }

    @ExceptionHandler(MissingServletRequestParameterException.class)
    public ResponseEntity<ApiResponse<Void>> handle(MissingServletRequestParameterException ex, HttpServletRequest request) {
        log.warn("[{}] {} missing param: {}", request.getMethod(), request.getRequestURI(), ex.getParameterName());
        return ResponseEntity.badRequest()
                .body(ApiResponse.badRequest("缺少必填参数: " + ex.getParameterName()));
    }

    @ExceptionHandler(IllegalArgumentException.class)
    public ResponseEntity<ApiResponse<Void>> handle(IllegalArgumentException ex, HttpServletRequest request) {
        log.warn("[{}] {} illegal argument: {}", request.getMethod(), request.getRequestURI(), ex.getMessage());
        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, HttpServletRequest request) {
        log.warn("[{}] {} request body unreadable: {}", request.getMethod(), request.getRequestURI(), ex.getMessage());
        return ResponseEntity.badRequest().body(ApiResponse.badRequest("请求体格式错误"));
    }

    @ExceptionHandler(MaxUploadSizeExceededException.class)
    public ResponseEntity<ApiResponse<Void>> handle(MaxUploadSizeExceededException ex, HttpServletRequest request) {
        log.warn("[{}] {} file too large: {}", request.getMethod(), request.getRequestURI(), ex.getMessage());
        return ResponseEntity.badRequest().body(ApiResponse.badRequest("文件大小超出限制"));
    }

    @ExceptionHandler(HttpRequestMethodNotSupportedException.class)
    public ResponseEntity<ApiResponse<Void>> handle(HttpRequestMethodNotSupportedException ex, HttpServletRequest request) {
        log.warn("[{}] {} method not supported: {}", request.getMethod(), request.getRequestURI(), ex.getMethod());
        return ResponseEntity.status(HttpStatus.METHOD_NOT_ALLOWED)
                .body(ApiResponse.error(405, "请求方法不支持: " + ex.getMethod()));
    }

    @ExceptionHandler(Exception.class)
    public ResponseEntity<ApiResponse<Void>> handle(Exception ex, HttpServletRequest request) {
        log.error("[{}] {} unhandled exception: {}", request.getMethod(), request.getRequestURI(), ex.getMessage(), ex);
        return ResponseEntity.internalServerError()
                .body(ApiResponse.error(500, "服务器内部错误"));
    }

    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;
        };
    }
}