GIF Mashups pre gifnik na rouming.cz v0.2

// ==UserScript==
// @name         GIF Mashups pre gifnik na rouming.cz
// @namespace    http://rouming.cz
// @version      0.2
// @description  license: WTFPL (Do What the Fuck You Want To Public License)
// @author       janci
// @match        http://www.rouming.cz/roumingGIF.php*
// @grant        none
// ==/UserScript==

/*
  GIF Mashups pre gifnik na rouming.cz
  autor: janci
  license: WTFPL (Do What the Fuck You Want To Public License)
*/
var komenty = document.querySelectorAll(".roumingForumMessage a");
var miestecko = document.querySelector(".roumingForumMessage a").parentNode;
var yt;

[].forEach.call(komenty, function(koment){
  if(koment.href.search(/https?:\/\/(www\.)?(youtube\.com\/watch|youtu.be\/)/) >= 0){
    var mashupator = document.createElement("a");
    mashupator.innerHTML = "[MashItUp]";
    mashupator.href="#";
    mashupator.onclick = mashupHandler(koment.href);
    koment.parentNode.appendChild(mashupator);
    console.log(mashupator);
  }
});

function ytembedlink(url){
    var regExp = /^.*((youtu.be\/)|(v\/)|(\/u\/\w\/)|(embed\/)|(watch\?))\??v?=?([^#\&\?]*).*/;
    var match = url.match(regExp);
    var starttime = 0;
    var startmatch = url.match(/[\?&]t=([0-9]*)/);
    if(startmatch && startmatch[1]>0){
      starttime = startmatch[1];
    }
    return "https://www.youtube.com/embed/"+match[7]+"?autoplay=1&loop=1&playlist="+match[7]+"&showinfo=0&start="+starttime;
}

function mashupHandler(url){
  return function(){
    if(!yt){
      yt = document.createElement("iframe");
      yt.width = 300;
      yt.height = 50;
      yt.frameBorder = 0;
      yt.setAttribute("allowfullscreen", "allowfullscreen");
      yt.setAttribute("mozallowfullscreen", "mozallowfullscreen");
      yt.setAttribute("msallowfullscreen", "msallowfullscreen");
      yt.setAttribute("oallowfullscreen", "oallowfullscreen");
      yt.setAttribute("webkitallowfullscreen", "webkitallowfullscreen");
      miestecko.appendChild(yt);
      yt.onload = resetgif;
    }
    var link = ytembedlink(url);
    yt.src = ytembedlink(url);
  };
}

function resetgif(){
  var gif = document.querySelector(".roumingForumMessage img");
  if(gif){
    gif.src = gif.src;
  }
  var video = document.querySelector(".roumingForumMessage a video");
  if(video){
    video.currentTime = 0;
  }
}