var express=require('express');
var https=require('https');5 var fs = require("fs");
var crypto = require('crypto');

app.get("/getconfig",function (req,res) {
  res.header("Access-Control-Allow-Origin", "*");
  res.header('Access-Control-Allow-Methods', 'PUT, GET, POST, DELETE, OPTIONS');
  res.header("Access-Control-Allow-Headers", "X-Requested-With");
  res.header('Access-Control-Allow-Headers', 'Content-Type');
  res.send({
        code:"200",
        data:{},
        result:true
      });
      res.end("");
});
app.listen(8000);

//写入文件
function whiteFile(obj,callback){
  fs.writeFile(obj.fileName,obj.data,{flag:"w"},function (err) {
    if(err){
      console.error(obj.name+"文件写入错误");
      console.log(err);
      return;
    }
    console.log('文件写入成功');
    callback(obj.data);
  });
}
//读取文件信息
function readFile(obj,callback,errback){
  fs.readFile(obj.fileName,"utf-8",function (err,data) {
    if(err){
      console.error(obj.name+"读取错误");
      return errback(callback);
    }
    //console.log(data);
    if(!data){
      errback(callback);
    }else{
      console.log(data);
      callback(data);
    }
  });
}

//发送一个http get请求
function sendGetRequest(options,callback){
  var httpReq=https.request(options, function(httpRes) {
    httpRes.on('data',function(chun){
      callback(chun);
    });
    httpRes.on('end',function(){});
  });
  httpReq.on('error',function(err){
    console.log("接口调用失败");
  });
  httpReq.end();
}

//获取access_token
function getToken(callback){
  readFile({
    fileName:"./access_token.txt",
    name:"access_token"
  },callback,function(cb){
    var options={
      hostname:"api.weixin.qq.com",
      path:"/cgi-bin/token?grant_type=client_credential&appid=您的appid&secret=你的appid对应的密码",
      method:'GET'
    };
    sendGetRequest(options,function(chun){
      var resObj = JSON.parse(chun.toString());
      resObj.timestamp = Math.floor((new Date().getTime())/1000);
      var res = JSON.stringify(resObj);
      //console.log(res);
      try {
        whiteFile({
          fileName:"./access_token.txt",
          data:res,
          name:"access_token"
        },cb);
      }catch(err){
        console.log("文件写入失败");
        console.log("access_token:"+res);
        cb(res);
      }
    });
  });
}

//获取ticket
function getTicket(callback){
  readFile({
    fileName:"./ticket.txt",
    name:"ticket"
  },callback,function(cb) {
    getToken(function(tokenData){
      var token = JSON.parse(tokenData);
      //console.log("token:"+JSON.stringify(token));
      //callback({code:"200",data:{"data":token},result:true});
      var options = {
        hostname: "api.weixin.qq.com",
        path: "/cgi-bin/ticket/getticket?access_token=" + token.access_token + "&type=jsapi",
        method: 'GET'
      };
      sendGetRequest(options, function (chun) {
        var resObj = JSON.parse(chun.toString());
        resObj.timestamp = Math.floor((new Date().getTime())/1000);
        var res = JSON.stringify(resObj);
        if (resObj.errcode == 42001) {
          getToken(function(){
            getTicket(callback);
          });
        } else if (resObj.ticket) {
          try {
            whiteFile({
              fileName:"./ticket.txt",
              data:res,
              name:"ticket"
            },callback);
          }catch(err){
            console.log("文件写入失败");
            console.log("ticket:"+res);
            callback(res);
          }
        } else {
          callback(res);
        }

      });
    });
  });
}

getTicket(function(data){
      var dataObj = JSON.parse(data);
      var noncestr = "zhangchenguang";
      var timestamp = Math.floor((new Date().getTime())/1000);
      var url = "http://api-loan.zhmf.com/html/test/testshare.html";
      var obj = {
        noncestr,timestamp,url,jsapi_ticket:dataObj.ticket
      };
      var arr = ["noncestr","jsapi_ticket","timestamp","url"].sort();
      var string1 = "";
      for(var i = 0; i < arr.length; i++){
        string1 += (arr[i]+"="+obj[arr[i]])+"&";
      }
      string1 = string1.slice(0,string1.length-1);
      console.log(string1);
      var shasum = crypto.createHash('sha1');
      shasum.update(string1);
      var signature = shasum.digest("hex");
      console.log(signature);
    });

app.get("/getconfig",function (req,res) {
  res.header("Access-Control-Allow-Origin", "*");
  res.header('Access-Control-Allow-Methods', 'PUT, GET, POST, DELETE, OPTIONS');
  res.header("Access-Control-Allow-Headers", "X-Requested-With");
  res.header('Access-Control-Allow-Headers', 'Content-Type');
    getTicket(function(data){
      var dataObj = JSON.parse(data);
      var noncestr = "zhangchenguang";
      var timestamp = Math.floor((new Date().getTime())/1000);
      var url = "http://api-loan.zhmf.com/html/test/testshare.html";
      var obj = {
        noncestr,timestamp,url,jsapi_ticket:dataObj.ticket
      };
      var arr = ["noncestr","jsapi_ticket","timestamp","url"].sort();
      var string1 = "";
      for(var i = 0; i < arr.length; i++){
        string1 += (arr[i]+"="+obj[arr[i]])+"&";
      }
      string1 = string1.slice(0,string1.length-1);
      console.log(string1);
      var shasum = crypto.createHash('sha1');
      shasum.update(string1);
      var signature = shasum.digest("hex");
      console.log(signature);
      res.send({
        code:"200",
        data:{
          noncestr:noncestr,
          timestamp:timestamp,
          appId:"wx23599cdec409383c",
          signature:signature
        },
        result:true
      });
      res.end("");
    });
});