import axios from "axios";
import router from "@/router/index.js";
import { ElMessage } from 'element-plus';
let isRefreshing = false;
let requests = [];

// 错误处理函数
const handleResponseError = (result) => {
    if (result.status !== 200) {
        router.push("/login");
    }
    if (result.data.message === "NOT_LOGIN" || [2, 3, 4].includes(result.data.code)) {
              // 检测到token过期
      if (isRefreshing == false) {
        isRefreshing = true;
        
        // 这里需要替换为实际的refresh token请求
        return axios.post('https://uc.ljsea.top/user/refresh_token', {
          refresh_token: localStorage.getItem("refresh_token")
        },{
          headers: {
            'Authorization': `Bearer ${localStorage.getItem("refresh_token")}`
          }
        }).then(res => {
          const token = res.data["data"]["access_token"];
          localStorage.setItem("token", token);
          
          // 重试所有挂起的请求
          requests.forEach(cb => cb(token));
          requests = [];
          isRefreshing = false;
          
          // 重试当前请求
          const config = result.config;
          config.headers.Authorization = `Bearer ${token}`;
          return request(config);
        }).catch(err => {
          // 刷新token失败，跳转登录
          ElMessage.error('登录已过期，请重新登录！12');
          router.push("/login");
          return Promise.reject(err);
        });
      } else if (isRefreshing) {
        // 正在刷新token，将请求放入队列
        return new Promise(resolve => {
          requests.push(token => {
            result.config.headers.Authorization = `Bearer ${token}`;
            resolve(request(result.config));
          });
        });
      } 
    }
    if (result.data.code === 7) {
        ElMessage.error('该用户已存在，请重新输入！');
        return null;
    }
    if (result.data.code === 1) {
        ElMessage.error('请求失败，请稍后重试！');
    }
    return result.data;
};

// 请求实例缓存
const instances = new Map();

// 请求工厂函数（单例模式）
export const createRequestInstance = (baseURL, config = {}) => {
    // 检查是否已存在该域名的实例
    if (instances.has(baseURL)) {
        return instances.get(baseURL);
    }
    
    // 创建新实例
    const instance = axios.create({
        baseURL,
        timeout: 10000, // 默认超时时间
        headers: {
            'Content-Type': 'application/json'
        },
        ...config
    });

    // 添加响应拦截器
    instance.interceptors.response.use(
        result => handleResponseError(result),
        error => {
            ElMessage.error('请求失败，请稍后重试！');
            return Promise.reject(error);
        }
    );

    // 缓存实例
    instances.set(baseURL, instance);
    
    return instance;
};

// 默认导出原有的阿里云请求实例
export default createRequestInstance("https://tx.ljsea.top/");