// parse url by youtube using expression regular
function youtubeParser(url) {
  var regExp = /^.*((youtu.be\/)|(v\/)|(\/u\/\w\/)|(embed\/)|(watch\?))\??v?=?([^#\&\?]*).*/;
  var match = url.match(regExp);

  if (match && match[7].length == 11) {
    return b = match[7];
  } else {
    alert('<%= I18n.t('admin.actions.content_builder.invalid_url')%>');
  }
}