index.js

const functions = require("firebase-functions");
const admin = require("firebase-admin");
admin.initializeApp();

const axios = require("axios");
const LINE_MESSAGING_API = "https://api.line.me/v2/bot";
const LINE_HEADER = {
  "Content-Type": "application/json",
  Authorization: `Bearer YOUR-ACCESS-TOKEN`
};

const msgTemplate = require("./msgTemplate");
const ONEROUND_KM = 1;

exports.LineWebhook = functions.https.onRequest(async (req, res) => {
  const event = req.body.events[0];
  let payload = null;
  const monthAndWeek = getMonthAndWeek()
  const userProfile = await getUserProfile(event.source.userId);

  if (event.type === "beacon") {
    const status = await admin.database().ref(monthAndWeek).child(userProfile.userId).child("status").once('value');

    if (status.val() === null || status.val() === 'finish') {
      // นักวิ่งเข้ามาในระยะ Beacon เพื่อเตรียมตัวกำลังจะเริ่มวิ่ง
      // ส่งข้อความหานักวิ่งว่าพร้อมไหม?
      payload = msgTemplate.ready();

    } else if (status.val() === 'running') {
      // วิ่งเข้ามาในระยะ Beacon 1 ครั้ง = 1 รอบ = 1 KM 
      let totalDistance = await admin.database().ref(monthAndWeek).child(userProfile.userId).child("totalDistance").once('value');

      // ทำการบวกระยะเพิ่มให้นักวิ่ง
      totalDistance = totalDistance.val() + ONEROUND_KM;
      await admin.database().ref(monthAndWeek).child(userProfile.userId).set({
        "totalDistance": totalDistance,
        "pictureUrl": userProfile.pictureUrl,
        "displayName": userProfile.displayName,
        "status": "running"
      })

      // ส่งข้อความยืนยันให้นักวิ่งว่าเก็บเพิ่มอีก 1 KM 
      payload = msgTemplate.submitDistance(totalDistance);
    }

  } else if (event.type === 'postback' && event.postback.data === 'running') {
    // นักวิ่งเข้ามาในระยะ Beacon เพื่อเตรียมตัวกำลังจะเริ่มวิ่ง
    // นักวิ่งกดปุ่ม I'm ready, GO! เพื่อเริ่มนับ KM
    await admin.database().ref(monthAndWeek).child(userProfile.userId).child("status").set("running");
    payload = msgTemplate.go();

  } else if (event.type === 'postback' && event.postback.data === 'finish') {
    // นักวิ่งกดปุ่ม I'm done เพื่อหยุดการนับ KM
    await admin.database().ref(monthAndWeek).child(userProfile.userId).child("status").set("finish");

    let flexBody = await createFlexLeaderboard();
    payload = msgTemplate.leaderboardHeader(flexBody, monthAndWeek);

  } else if (event.type === 'message' && event.message.text === 'Leaderboard') {
    // กด Richmenu เพื่อดู Ranking
    let flexBody = await createFlexLeaderboard();
    payload = msgTemplate.leaderboardHeader(flexBody, monthAndWeek);

  }
  await reply(event.replyToken, payload);
  return res.end();
});

const createFlexLeaderboard = async () => {
  const monthAndWeek = getMonthAndWeek()
  let body = [];
  let arr = [];
  const snapshot = await admin.database().ref(monthAndWeek).orderByChild("totalDistance").once('value');
  snapshot.forEach((childSnapshot) => {
    let displayName = childSnapshot.child("displayName").val();
    let totalDistance = childSnapshot.child("totalDistance").val();
    let pictureUrl = childSnapshot.child("pictureUrl").val();
    arr.push([totalDistance, pictureUrl, displayName]);
  });
  arr.sort(sortFunction);
  arr.forEach(val => {
    body.push(msgTemplate.leaderboardBody(
      val[1], val[2], val[0].toFixed(2)));
  });
  return body;
}

function sortFunction(a, b) {
  if (a[0] === b[0]) {
    return 0;
  }
  else {
    return (a[0] > b[0]) ? -1 : 1;
  }
}

const getMonthAndWeek = () => {
  var d = new Date();
  var date = d.getDate();
  var day = d.getDay();

  var weekOfMonth = Math.ceil((date + 6 - day) / 7);

  var month = new Array();
  month[0] = "January";
  month[1] = "February";
  month[2] = "March";
  month[3] = "April";
  month[4] = "May";
  month[5] = "June";
  month[6] = "July";
  month[7] = "August";
  month[8] = "September";
  month[9] = "October";
  month[10] = "November";
  month[11] = "December";
  var thisMonth = month[d.getMonth()];

  return thisMonth + " - Week " + weekOfMonth;
}

const getUserProfile = async (userId) => {
  const userProfile = await axios({
    method: "get",
    headers: LINE_HEADER,
    url: `${LINE_MESSAGING_API}/profile/` + userId
  });
  return userProfile.data;
}

const reply = async (replyToken, payload) => {
  await axios({
    method: "post",
    url: `${LINE_MESSAGING_API}/message/reply`,
    headers: LINE_HEADER,
    data: JSON.stringify({
      replyToken: replyToken,
      messages: [payload]
    })
  });
};