Script for downloading audio and video files from the vk.com

VkGetLink.user.js

// ==UserScript==
// @name VKGetLink
// @description Script for downloading audio and video files from the vk.com. Based on Ivan Snegirev's VK-Downloader http://userscripts-mirror.org/scripts/show/151571
// @author Mist Poryvaev
// @version 1.0.2
// @include https://*vk.com/*
// @grant none
// ==/UserScript==

function audio()
{
  var main_div=document.getElementsByClassName("area clear_fix");
  for(var i=0;i<main_div.length;i++)
  { 
    if(main_div[i].parentNode.firstChild.href)
    {
    	main_div[i].parentNode.firstChild.style.top=main_div[i].getElementsByClassName("play_new")[0].offsetTop+"px";
    	continue;
    }
    var _mp3_=main_div[i].getElementsByTagName("input")[0].value.split(",")[0].split("?")[0];
    var _b_=main_div[i].getElementsByTagName("b")[0];
    var _top_=document.getElementById(main_div[0].parentNode.id.replace("audio","play")).offsetTop+"px";
    var _t_=main_div[i].getElementsByClassName("play_new")[0].offsetTop+"px";
    var _info_;
    if (main_div[i].getElementsByClassName("info").length != 0)
    {
        _info_ = main_div[i].getElementsByClassName("info")[0]
    }
    else
    {    
      _info_ = main_div[i].getElementsByClassName("info fl_l")[0];
    }
    var _a_tmp_ = _info_.getElementsByTagName("a");
    var _title_ = _a_tmp_[0].innerHTML + " - ";
    if (_a_tmp_.length == 1)
    {
    	_title_ = _title_ + _info_.getElementsByTagName("span")[0].innerHTML;
    }
    else
    {
    	_title_ = _title_ + _a_tmp_[1].innerHTML;
    }
    var _a_=document.createElement("a");
    _a_.href=_mp3_;
    _a_.target="_blank";
    _a_.innerHTML="&nbsp;▼";
    _a_.download =_title_ + ".mp3";
    _a_.style.zIndex="10";
    _a_.style.left="30px";
    _a_.style.top=_t_;
    _a_.style.position="absolute";
    _a_.style.color="white";
    _a_.style.backgroundColor="#5e82a8";
    _a_.style.border="#395A7C";
    _a_.style.width="16px";
    _a_.style.height="16px";
    main_div[i].parentNode.insertBefore(_a_,main_div[i].parentNode.firstChild);
    _b_.style.paddingLeft="25px";
  }
}

function video()
{
  if(document.getElementsByClassName("video_box_wrap")[0] && !document.getElementById('download') && document.getElementById('video_player').tagName!='IFRAME')
  {
    var inner_video="";
    var f=encodeURI(unescape(document.getElementsByClassName("video_box_wrap")[0].innerHTML.split(" ")[8].split('"')[1].replace(/amp;/g,"")));
    var flashvars=f.split("&");
    var o = new Object();
    var name=new Array();
    var content=new Array();
    var title = document.getElementById("mv_title").innerHTML.replace("\"","");

    for(var c=0;c<=flashvars.length-1;c++)
    {
      name[c]=flashvars[c].split("=")[0];
      content[c]=flashvars[c].split("=")[1];
    }

    for(var c2=0;c2<=name.length;c2++)
    {
      o[name[c2]]=content[c2];
    }

    var _url_;
    var _size;
    if (o.url1080)
    {
      _url_ = o.url1080.split("?")[0];
      _size_ = "1080";
    }
    else
    if (o.url720)
    {
      _url_ = o.url720.split("?")[0];
      _size_ = "720";
    }
    else
    if (o.url480)
    {
      _url_ = o.url480.split("?")[0];
      _size_ = "480";
    }
    else
    if (o.url360)
    {
      _url_ = o.url360.split("?")[0];
      _size_ = "360";
    }
    else
    if (o.url240)
    {
      _url_ = o.url240.split("?")[0];
      _size_ = "240";
    }

    if (_url_.length != 0)
    {
      inner_video="<a style='color:white;background-color:#5e82a8;padding:5px 5px 2px 5px;border:#395A7C;'  target='_blank' href='"+_url_+"' download='"+title+"'>"+_size_+"▼</a> ";
      
      var video_download=document.createElement("div");
      video_download.style.width="auto";
      video_download.style.height="auto";
      video_download.style.paddingBottom="5px";
      video_download.id="download";
      video_download.innerHTML=inner_video;
      document.getElementById("mv_more").parentNode.appendChild(video_download);
    }
  }
}

setInterval(function()
{
  if(document.getElementsByClassName("area clear_fix").length!=0)
  {
    audio();
  }
  if(document.getElementById('video_player'))
  {
    video();
  }
}, 400);