# Payment Features Page

// functional-pages/request-payment.js
exports.beforeRequestPayment = function (paymentArgs, callback) {
  // Note:
  // The function page function (this function) should not be Require Other non functional-pages Files in the directory,
  // Other non functional-pages Files in the directory should also not be Require The files in this directory,
  // Like this Require Calls will not be supported in the future.
  //
  // to be with functional-pages The files in the Require
  var getOpenIdURL = Require('./URL').getOpenIdURL
  var paymentURL = Require('./URL').paymentURL

  // Custom parameters passed from the plug-in 'A'
  var customArgument = paymentArgs.customArgument

  // Step 1: Call wx.login Method acquisition Code, and then call the WeChat interface in the service end to use Code In exchange for the user. openId
  // Specific Document Reference https://mp.weixin.qq.com/debug/wxadoc/dev/api/API-Login .html?t=20161230#wxloginobject
  wx.login({
    success: function (Data) {
      wx.request({
        url: getOpenIdURL,
        data: { code: data.code },
        success: function (res) {
          // Pull User Openid  success
          // The second step: call the service to pay a unified order, return the payment parameters. Development here and the ordinary wx.requestPayment identical
          // Documentation can refer to the https://pay.weixin.qq.com/Wiki/doc/api/wxa/wxa_api.php?chapter=7_4&index=3
          wx.request({
            url: paymentURL,
            data: { openid: res.data.openid },
            method: 'POST',
            success: function (res) {
              console.log('unified order success, response is:', res)
              var Payargs  = res.data.payargs
              // Step 3: Call the callback function callback Make a payment
              // in callback You need to return two parameters: err and requestPaymentArgs：
              // err Should be null (or some failure information)
              // requestPaymentArgs Will be used to call the Wx.requestpayment, in addition to success/fail/complete Unsupported,
              // Should be associated with wx.requestPayment Same parameters.
              var error = null
              var requestPaymentArgs = {
                timeStamp: payargs.timeStamp,
                NonceStr::  payargs.nonceStr, 
                package: payargs.package,
                signType: payargs.signType,
                paySign: payargs.paySign,
                extraData: { // use extraData Delivering custom data
                  timeStamp: payargs.timeStamp
                },
              }
              callback(error, requestPaymentArgs)
            }
          })
        },
        fail: function (res) {
          console.log('pull user Openid  Failure, will not be able to use the open interface and other services, res)
          // callback The first argument is an error message. The error message is returned
          callback(res)
        }
      })
    },
    fail: function (err) {
      console.log('wx.login Interface call failure, will not be able to use the open interface and other services, " err)
      // callback The first argument is an error message. The error message is returned
      callback(err)
    }
  })
}