import axios from 'axios';

import { Message, Loading } from 'element-ui';

import Cookies from 'js-cookie';

import router from '@/router/index'

let loading  //定義loading變量

function startLoading() { //使用Element loading-start 方法
 loading = Loading.service({
  lock: true,
  text: '加載中……',
  background: 'rgba(0, 0, 0, 0.7)'
 })
}
function endLoading() { //使用Element loading-close 方法
 loading.close()
}
//那么 showFullScreenLoading() tryHideFullScreenLoading() 要干的事兒就是將同一時刻的請求合并。
//聲明一個變量 needLoadingRequestCount，每次調用showFullScreenLoading方法 needLoadingRequestCount + 1。
//調用tryHideFullScreenLoading()方法，needLoadingRequestCount - 1。needLoadingRequestCount為 0 時，結束 loading。
let needLoadingRequestCount = 0
export function showFullScreenLoading() {
 if (needLoadingRequestCount === 0) {
  startLoading()
 }
 needLoadingRequestCount++
}

export function tryHideFullScreenLoading() {
 if (needLoadingRequestCount <= 0) return
 needLoadingRequestCount--
 if (needLoadingRequestCount === 0) {
  endLoading()
 }
}

//http request 攔截器
axios.interceptors.request.use(
 config => {
  var token = ''
  if(typeof Cookies.get('user') === 'undefined'){
   //此時為空
  }else {
   token = JSON.parse(Cookies.get('user')).token
  }//注意使用的時候需要引入cookie方法，推薦js-cookie
  config.data = JSON.stringify(config.data);
  config.headers = {
   'Content-Type':'application/json'
  }
  if(token != ''){
   config.headers.token = token;
  }
  showFullScreenLoading()
  return config;
 },
 error => {
  return Promise.reject(err);
 }
);


//http response 攔截器
axios.interceptors.response.use(
 response => {
  //當返回信息為未登錄或者登錄失效的時候重定向為登錄頁面
  if(response.data.code == 'W_100004' || response.data.message == '用戶未登錄或登錄超時，請登錄！'){
   router.push({
    path:"/",
    querry:{redirect:router.currentRoute.fullPath}//從哪個頁面跳轉
   })
  }
  tryHideFullScreenLoading()
  return response;
 },
 error => {
  return Promise.reject(error)
 }
)