Play ringing when no early media

[michaelrkn]

If the call does not produce "early media", we should play a recording of a ringing sound. https://www.twilio.com/docs/voice/client/javascript/connection#onringing-handlerhasearlymedia

[michaelrkn]

This isn't as simple as it seems. You'd think you could just write:

connection.on('ringing', (hasEarlyMedia) => {
    console.log(hasEarlyMedia);
    if (!hasEarlyMedia) {
      var audio = new Audio('ring.mp3');
      audio.play();
    }
  });

But what happens is that ringing will fire as soon as the dial is made, and hasEarlyMedia will always be false at this point. Then, if there is actually a ringing sound, ringing will fire again, and hasEarlyMedia will be true.

So ideally after the first ringing fires, we'd set a timer for 5 seconds (or something), and then start playing a ringing sound, and then stop the ringing sound if ringing fires again, or if the call is answered, or if the connection is closed.