let express = require("express");const https = require('https');
let app = express();
//appIDlet 
appID = `wxec6fa9e9bc03d885`;
//appsecretlet 
appSerect = `4c8a0d14cff08959b4e17334cabf9cf0`;
//點(diǎn)擊授權(quán)后重定向url地址
let redirectUrl = `/getUserInfo`;
let host = `http://127.0.0.1:3000`;
//微信授權(quán)api,接口返回code,點(diǎn)擊授權(quán)后跳轉(zhuǎn)到重定向地址并帶上code參數(shù)
let authorizeUrl = `https://open.weixin.qq.com/connect/oauth2/authorize?appid=${appID}&redirect_uri=` +  `${host}${redirectUrl}&response_type=code&scope=snsapi_userinfo&state=STATE#wechat_redirect`
app.get("/login", function(req, res) {  
  res.sendFile(path.resolve(__dirname,'login.html'));
});
app.get("/auth", function(req, res) {  
  res.writeHead(302, {  
    'Location': authorizeUrl 
   });  
  res.end();
});
app.get("/getUserInfo", function(req, res) {  
  let code = req.query.code;  
  let getaccess = `https://api.weixin.qq.com/sns/oauth2/access_token?appid=` + `${appID}&secret=${appSerect}&code=$[code]&grant_type=authorization_code`;  
  //通過(guò)拿到的code和appID、app_serect獲取access_token和open_id  
  https.get(getaccess, (resText) => {    
    var ddd = "";    
    resText.on('data', (d) => {
      ddd += d;    
    });
    resText.on('end', () => {
      // console.log(ddd);
      var obj = JSON.parse(ddd);
      var access_token = obj.access_token; 
      var open_id = obj.openid;      
      //通過(guò)上一步獲取的access_token和open_id獲取userInfo即用戶(hù)信息
      let getUserUrl = `https://api.weixin.qq.com/sns/userinfo?access_token=${access_token}&openid=${open_id}⟨=zh_CN`;
      https.get(getUserUrl, (resText) => {
        user = "";
        resText.on('data', (d) => {
          user += d;
        });
        resText.on('end', () => {
          console.log(user);
          var userobj = JSON.parse(user);
          res.send(userobj);
          console.log(userobj);
        });
      })    });
  }).on('error', (e) => {
    console.error(e);
  }); 

app.listen(3000);

async function wxAuth(req, res) {
  //解析querystring獲取URL中的code值  
  let code = req.query.code;
  //通過(guò)拿到的code和appID、app_serect獲取返回信息
  let resObj = await getAccessToken(code);
  //解析得到access_token和open_id
  let access_token = resObj.access_token;
  let open_id = resObj.openid;
  //通過(guò)上一步獲取的access_token和open_id獲取userInfo即用戶(hù)信息
  let userObj = await getUserInfo(access_token, open_id);
  console.log(userObj);
  res.render(path.resolve(__dirname,'userInfo.ejs'), {userObj: userObj});
  // res.send(userObj);}

//通過(guò)拿到的code和appID、app_serect獲取access_token和open_id
function getAccessToken(code) {
  return new Promise( (resolve, reject) => {
    let getAccessUrl = `https://api.weixin.qq.com/sns/oauth2/access_token?appid=` + `${appID}&secret=${appSerect}&code=$[code]&grant_type=authorization_code`;
    https.get(getAccessUrl, (res) => {
      var resText = "";
      res.on('data', (d) => { 
        resText += d; 
      });
      res.on('end', () => {
        var resObj = JSON.parse(resText);
        resolve(resObj);
      });
    }).on('error', (e) => {
      console.error(e);
    });
  });
  }
//通過(guò)上一步獲取的access_token和open_id獲取userInfo即用戶(hù)信息
function getUserInfo(access_token, open_id) {
  return new Promise( (resolve, reject) => {
    let getUserUrl = `https://api.weixin.qq.com/sns/userinfo?access_token=${access_token}&openid=${open_id}⟨=zh_CN`;
    https.get(getUserUrl, (res) => {
      var resText = ""; 
      res.on('data', (d) => {
        resText += d;
      });
      res.on('end', () => {
        var userObj = JSON.parse(resText);
        resolve(userObj);
      });
    }).on('error', (e) => {
      console.error(e);
    });
  })}