Adobe Air Download Youtube Videos

var fileName;
var swfArg = [];
 
// Get the file name.
 
function getVInfo(url) {
		var req = new XMLHttpRequest();
               req.onreadystatechange = function() {
                    if (req.readyState == 4) {
                        var str = req.responseText;
			var stra = str.split("\n");
			var n = 0;
			var n2 = 0;
			var n3 = 0;
			while (n < stra.length) {
			if (stra[n].indexOf("title") != -1 && n2 == 0) {
				n2 = n;
				if (n3 != 0) {
				n = stra.length;
			}
			}
			if (stra[n].indexOf("swfArgs") != -1 && n3 == 0) {
			n3 = n;
			if (n2 != 0) {
			n = stra.length;
			}
			}
			n = n + 1;
			}
			swfArg = stra[n3].split(',');
			fileName = stra[n2];
			fileName = fileName.replace("<title>", "");
			fileName = fileName.replace("</title>", "");
			fileName = "YouTube Downloader/" + fileName.replace("YouTube - ", "") + ".flv";
			fileName = fileName.replace("	", "");
			downVideo(document.getElementById("yurl").value);
                    }
                };
                req.open('GET', url, true);
                req.send(null);
 
			}
	function downVideo(url){
		var n = url.indexOf('v=');
		var n2 = url.indexOf('&', n);
		var len;
		if (n2 != -1) {
		len = n2 - 1;
		}
		else {
			len = url.length;
		}
		var vid = url.substr(n + 2, len);
		la = swfArg[3].split(': ');
		l = la[1].replace("\"", "");
		ska = swfArg[4].split(': ');
		sk = ska[1].replace("\"", "");
		ta = swfArg[5].split(': ');
		t = ta[1].replace("\"", "");
		ha = swfArg[6].split(': ');
		hl = ha[1].replace("\"", "");
		pa = swfArg[7].split(': ');
		plid = pa[1].replace("\"", "");
		var url = 'http://youtube.com/get_video.php?video_id=' + vid + '&l=' + l + '&sk=' + sk + '&t=' + t + '&hl=' + hl + '&plid=' + plid;
		var request = new air.URLRequest(url);
		var urlStream = new air.URLStream();
		var fileData = new air.ByteArray();
		urlStream.addEventListener( air.ProgressEvent.PROGRESS, doProgress );
		urlStream.addEventListener(air.Event.COMPLETE, completeHandler);
		try {
			urlStream.load(request);
		}
		catch (error) {
			air.trace("Unable to load URL: " + error);
		}
 
	function completeHandler(event){
	urlStream.readBytes(fileData, 0, urlStream.bytesAvailable);
	var file = air.File.documentsDirectory;
	var fileStream = new air.FileStream();
        file = file.resolvePath(fileName);
	fileStream.open(file, air.FileMode.WRITE);
	fileStream.writeBytes(fileData, 0, fileData.length);
	fileStream.close();
	document.getElementById("crap").innerHTML = "Done downloading " + fileName.replace("YouTube Downloader/", "");
				}
			}
function doProgress( e )
{
	var loaded = e.bytesLoaded;
	var total = e.bytesTotal;
	var pct = Math.ceil( ( loaded / total ) * 100 );
 
	document.getElementById( 'crap' ).innerText = 'Downloading... ' + pct.toString() + '%';
}

<input type="button" id="downb"  onclick='getVInfo(document.getElementById("yurl").value);' value='Download'/>