index.js

const login = require('facebook-chat-api');
const prettyjson = require('prettyjson');
const config = require('./config.json');
const cmd = require('node-cmd');
// remember to brew install shoptify
const SpotifyWebApi = require('spotify-web-api-node');
const spotifyApi = new SpotifyWebApi({
  clientId : config.spotifyid,
  clientSecret : config.spotifysecret
});
let api;
function prettyConsole(data) {
  console.log(prettyjson.render(data));
}

var queue_array = []; // array that queued songs are appended too
var pausedFromMessage = true; // variable so we're able to pause the music through messenger

async function listenFacebook(err, message) {
  var { body } = message;
  var body = body.toLowerCase(); // make everything lower case

  /* 
  User: "play <songname>"
  Bot: Sure, I'll play <songname> || Bot: Wait.. something does not sound right. Please try something else.
  */
  if ((body.indexOf('play') > -1) && (body.indexOf('@spotify') > -1)) { // has the word play
    const songToSearch = body.split("play ")[1];
    const searchResults = await spotifyApi.searchTracks(songToSearch);
    if (searchResults.body.tracks.items[0] != null) {
      const songToPlay = searchResults.body.tracks.items[0].uri;
      cmd.run(`spotify play uri ${songToPlay}`);
    }
    else {
      login({email: config.login, password: config.password}, function callback (err, api) {
        if(err) {
          return console.error(err);
        }
    var yourID = 1626794548;
    var msg = {body: "Wait.. something does not sound right. Please try something else"};
    api.sendMessage(msg, yourID);
      });
    }
  }

  // needs rework
  else if (body.indexOf('https://open.spotify.com/user') > -1 ) { // spotify playlist link
    const playlistIdentifier = body.split("playlist/")[1]; // grabs the unique playlist identifier
    //console.log(`playing spotify:user:kabirvirji:playlist:${playlistIdentifier}`);
    var user = config.username;
    cmd.run(`spotify play uri spotify:user:${user}:playlist:${playlistIdentifier}`);
  }

  else if (body.indexOf('queue') > -1 && (body.indexOf('@spotify') > -1)) { // has the word queue
    const songToSearchforQueue = body.split("queue ")[1]; // takes just the song name eg. "queue songname" will just take songname
    const searchResultsforQueue = await spotifyApi.searchTracks(songToSearchforQueue); // search results like before
    const songToQueue = searchResultsforQueue.body.tracks.items[0].uri; // index at URI instread of name like before
    if (searchResultsforQueue.body.tracks.items[0] != null) {
        queue_array.push(songToQueue);
        console.log(queue_array);
    } else {
      login({email: config.login, password: config.password}, function callback (err, api) {
        if(err) {
          return console.error(err);
        }
    var yourID = 1626794548;
    var msg = {body: "Wait.. something does not sound right. Please try something else"};
    api.sendMessage(msg, yourID);
      });
    }
  }

  else if (body.indexOf('pause') > -1) { 
    pausedFromMessage = false;
    clearInterval(myInterval);
    cmd.run(`spotify pause`);
  }

  else if (body.indexOf('unpause') > -1) { 
    cmd.run(`spotify play`);
  }

  else if (body.indexOf('next') > -1) { 
    cmd.run(`spotify next`);
  }

}

/* 
Checks every second using the 'spotify status' command to see if the song is paused.
If the song is paused, it means its over, and the next song in the array plays
*/
var myInterval = setInterval(function() {
  cmd.get(
    'spotify status',
    function(data) {
      console.log(data);
      //console.log(data.includes('paused')); // bool
      if (data.includes('paused') && pausedFromMessage) {
        //console.log(`The song is paused, so I'll play: ${queue_array}`);
        cmd.run('spotify play uri ' + queue_array[0]);
        queue_array.shift();
        //console.log(`After plaything queued song, the array looks like this: ${queue_array}`);
      }
    }
  )
}, 
1000);

async function init() {
  await initSpotify();
  api = await loginToFacebook();
  api.listen(listenFacebook);
}

async function initSpotify() {
  const { body } = await spotifyApi.clientCredentialsGrant();
  spotifyApi.setAccessToken(body['access_token']);
}

function loginToFacebook() {
  return new Promise((resolve, reject) => {
    login({ email: config.login, password: config.password }, (err, api) => {
      if (err) reject(err);
      resolve(api);
    })
  });
}

login({email: config.login, password: config.password}, function callback (err, api) {
    if(err) return console.error(err);
    var yourID = 1626794548;
    var msg = {body: "Hey! My name is Spotify Bot and I'm here to help you control your music! To play a song tell me to \"play <songname>\". To queue a song (add it to up next) tell me to \"queue <songname>\". Have fun 🎵"};
    api.sendMessage(msg, yourID);
});

login({email: config.login, password: config.password}, function callback (err, api) {
    if(err) return console.error(err);

    api.setOptions({listenEvents: true});

    var stopListening = api.listen(function(err, event) {
        if(err) 
          api.sendMessage("Sorry, that didn't quite work");

        switch(event.type) {
          case "message":
            if(event.body === '/stop') {
              api.sendMessage("Goodbye...", event.threadID);
              return stopListening();
            }
            api.markAsRead(event.threadID, function(err) {
              if(err) {
                console.log(err)
                api.sendMessage("Sorry, that didn't quite work");

              }
            });
            if(event.body.indexOf('@spotify') > -1 && ((event.body.indexOf('play') > -1) || event.body.indexOf('queue') > -1)){
            api.sendMessage("Sure, I'll" + event.body.replace("@spotify", ""), event.threadID);
          }
            if(event.body == '@spotify pause'){
              console.log('paused');
              // need to login again
              api.sendMessage("Paused", event.threadID);
            }
            if(event.body.indexOf('@spotify unpause') > -1){
              // need to login again
              api.sendMessage("Unpaused", event.threadID);
            }
            if(event.body == '@spotify next'){
              // need to login again
              api.sendMessage("Playing the next song!", event.threadID);
            }
            break;
          case "event":
            console.log(event);
            break;
        }
    });
});

init();