Refactor server code

[rbdr/junction] / extension / content_script.js

import { io } from 'socket.io-client';
import Peers from './peers';
import Media from './media';

const internals = {

  kSocketUrl: 'https://junction.tranquil.services',
	kIceServers: [
		{url:"stun:stun.l.google.com:19302"}
	],

  port: null,
  socket: null,
  peers: {},

  onMessage(message) {
    internals[message.action](message.data);
  },

  async joinAudioCall(data) {

    internals.tada = data.tada; // Keeping for fun

    try {
      const mediaStream = await Media.start();

      internals.socket = io(internals.kSocketUrl, {
        transports: ['websocket']
      });

      internals.socket.on('error', function(error) {

        console.error('GENERAL ERROR', error);
      });

      internals.socket.on('connect_error', function(error) {

        console.error('CONNNECT ERROR', error);
      });

      internals.socket.on('connect', function() {

        console.log('Connected to signaling server, group: ', data.currentUrl);
        internals.socket.emit('join', {
          room: data.currentUrl,
        });
      });

      internals.socket.on('disconnect', function() {

        console.log("disconnected from signaling server");
      });

      internals.socket.on('addPeer', function(data) {

          Peers.add(data.peerId, internals.tada);
          const peerId = data.peerId;

          const peerConnection = new RTCPeerConnection(
              { iceServers: internals.kIceServers },
              { optional: [{ DtlsSrtpKeyAgreement: true }] }
          );

          internals.peers[peerId] = peerConnection;
          mediaStream.getTracks().forEach((track) => {
            peerConnection.addTrack(track, localStream);
          });

          peerConnection.onicecandidate = (event) => {
            if (event.candidate) {
              internals.socket.emit('relayICECandidate', {
                peerId: peerId,
                candidate: event.candidate
              });
            }
          }

        const remoteStream = new MediaStream();
        peerConnection.ontrack = (event) => {
          remoteStream.addTrack(event.track);
          const remoteAudioElement = new Audio();
          remoteAudioElement.srcObject = remoteStream;
          remoteAudioElement.play();
        };

        peerConnection.onnegotiationneeded = async () => {
          console.log("Creating RTC offer to ", peerId);
          const offer = await peerConnection.createOffer();
          await peerConnection.setLocalDescription(offer);

          // Emit the offer to the peer
          socket.emit('relayOffer', { offer, peerId });
        };

        console.log(`There are now ${Peers.count()} participants`);
      });

      socket.on('offerReceived', async (data) => {

				const peerConnection = internals.peers[data.peerId];

        const offer = new RTCSessionDescription(data.offer);
        await peerConnection.setRemoteDescription(offer);

        const answer = await peerConnection.createAnswer();
        await peerConnection.setLocalDescription(answer);

        // Send the answer to the peer
        socket.emit('relayAnswer', { answer, peerId: data.peerId });
      });

      socket.on('answerReceived', async (data) => {

				const peerConnection = internals.peers[data.peerId];
        const answer = new RTCSessionDescription(data.answer);
				await peerConnection.setRemoteDescription(answer);
      });

      socket.on('ICECandidateReceived', async (data) => {

				const peerConnection = internals.peers[data.peerId];
        const candidate = new RTCIceCandidate(data.candidate);
        await peerConnection.addIceCandidate(candidate);
		  });


      internals.socket.on('removePeer', function() {

				delete internals.peers[data.peerId];
        Peers.remove('id-'+(Peers.count() - 1)); // This is only for testing, don't use count to remove ids.
        console.log(`There are now ${Peers.count()} participants`);
      });
    }
    catch (err) {

      internals.port.postMessage({
        action: 'error'
      });
      internals.port.disconnect();
    }
  },

  hangUp() {

    Peers.reset();
    Media.stop();
    internals.socket.close();
    internals.port.disconnect();
  }
};

internals.port = chrome.runtime.connect({ name:"content" });
internals.port.onMessage.addListener(internals.onMessage);

console.log('Content Script Loaded');

// Indicates to the background script that we executed correctly
true;