js replace all youtube urls in string with embed code

function youtubeReplace(str) {
  let regex = /http(?:s?):\/\/(?:www\.)?youtu(?:be\.com\/watch\?v=|\.be\/)([\w\-\_]*)(&(amp;)?‌​[\w\?‌​=]*)?/;
  let result = str.replace(regex, '<iframe width="560" height="315" src="https://www.youtube.com/embed/$1" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>');
  return result;
}

youtubeReplace("https://www.youtube.com/watch?v=jNQXAC9IVRw")