import axios from 'axios'
import { MessageBox, Message } from 'element-ui'
import { getToken, setToken, removeToken } from '@/utils/auth'
import { getParams } from '@/utils/index'
// create an axios instance
const service = axios.create({
  baseURL: process.env.VUE_APP_BASE_API, // url = base url + request url
  withCredentials: true, // send cookies when cross-domain requests
  timeout: 5000 // request timeout
})

// request interceptor
service.interceptors.request.use(
  config => {
    // do something before request is sent
    const token = getToken()
    // 判断是否cookie存在token
    if (token) {
      config.headers['token'] = token
    } else {
      const query = getParams()
      const queryToken = query.token ? query.token : '';
      config.headers['token'] = queryToken
      setToken(queryToken)
    }
    const params = config.params
    const data = config.data
    // 把params里空的参数去除
    params ? deleteEmptyItem(params) : ''
    // 把data里空的参数去除
    data ? deleteEmptyItem(data) : ''
    return config
  },
  error => {
    // do something with request error
    console.log(error) // for debug
    return Promise.reject(error)
  }
)

// response interceptor
service.interceptors.response.use(
  /**
   * If you want to get http information such as headers or status
   * Please return  response => response
  */

  /**
   * Determine the request status by custom code
   * Here is just an example
   * You can also judge the status by HTTP Status Code
   */
  response => {
    let res = response.data
    // 如果是返回的文件
    if (response.config.responseType == 'blob') {
      return res
    }
    // 兼容服务端返回的字符串数据
    if (typeof res === 'string') {
      res = res ? JSON.parse(res) : res
    }
    // if the custom code is not 0
    if (res.code !== 0) {
      if (res.code === 401) { // 401未登录
        errorMsg(res.msg || '未登录或者登陆状态已失效')
        // to re-login
        removeToken();
        // 方便我们本地调试，去修改URL的token
        location.href.indexOf('local') === -1 && (location.href = process.env.VUE_APP_LOGIN_URL)
      } else if (res.code === 500) {  // 500 服务器异常
        errorMsg(res.msg || '服务器异常')
      } else if (res.code === 406) {  // 406 没有权限
        errorMsg(res.msg || '您没有权限')
      } else {
        errorMsg(res.msg || '服务器异常')
      }
      return Promise.reject(res.message || 'error')
    } else {
      return res
    }
  },
  error => {
    console.log('err' + error) // for debug
    errorMsg(error.message)
    return Promise.reject(error)
  }
)

/**
 * 弹出错误提醒
 * @param {String} msg 消息
 */
function errorMsg(msg) {
  Message({
    message: msg,
    type: 'error',
    duration: 3 * 1000
  })
}

/**
 * 清空对象为空的属性
 * @param {Object} obj 处理对象 
 */
function deleteEmptyItem(obj) {
  for(let i in obj) {
    (obj[i] === '' || obj[i] === undefined || obj[i] === null) ? delete obj[i] : ''
  }
}

export default service