var currentItem = "";
var videoInPlay = false;
var tutorialInPlay = false;
var popupWindow;
var ieversion= getInternetExplorerVersion(); 

function getInternetExplorerVersion()
// Returns the version of Windows Internet Explorer or a -1
// (indicating the use of another browser).
{
   var rv = -1; // Return value assumes failure.
   if (navigator.appName == 'Microsoft Internet Explorer')
   {
      var ua = navigator.userAgent;
      var re  = new RegExp("MSIE ([0-9]{1,}[\.0-9]{0,})");
      if (re.exec(ua) != null)
         rv = parseFloat( RegExp.$1 );
   }
   return rv;
}

function FadeToBlack(percent) {
	document.getElementById("VideoMask").style.display = "block";
	var layer = document.getElementById("VideoMaskImage");

	if (!percent)
		percent = 0;

	percent += 5;
	if (percent <= 80) {
		layer.style.opacity = "0." + percent;
		layer.style.filter = "alpha(opacity = " + percent + ")";

		setTimeout("FadeToBlack(" + percent + ")", 50);
	}
}

function FadeToWhite(percent) {
	document.getElementById("VideoMask").style.display = "block";
	var layer = document.getElementById("VideoMaskImage");

	percent -= 5;
	if (percent > 0) {
		layer.style.opacity = "0." + percent;
		layer.style.filter = "alpha(opacity = " + percent + ")";

		setTimeout("FadeToWhite(" + percent + ")", 50);
	}
	else {
		document.getElementById("VideoMask").style.display = "none";
	}
}

function PlayVideo(videoFile, videoTitle) {
	if (ieversion > 0 && ieversion < 7) return true;
	if (videoFile.match(/\.flv$/)) {
		document.getElementById("VideoPlaceholder").innerHTML =
			"<embed id=\"FlashMovie\" src=\"640x480.swf?flv=" + videoFile + "\" " +
			"quality=\"high\" pluginspage=\"http://www.macromedia.com/go/getflashplayer\" " +
			"name=\"640x480\" allowscriptaccess=\"sameDomain\" " +
			"type=\"application/x-shockwave-flash\" width=\"640\" height=\"520\"></embed>";
	}
	else if (videoFile.match(/\.f4v$/)) {
		document.getElementById("VideoPlaceholder").innerHTML =
			"<embed id=\"FlashMovie\" src=\"640x480.swf?flv=" + videoFile + "\" " +
			"quality=\"high\" pluginspage=\"http://www.macromedia.com/go/getflashplayer\" " +
			"name=\"640x480\" allowscriptaccess=\"sameDomain\" " +
			"type=\"application/x-shockwave-flash\" width=\"640\" height=\"520\"></embed>";
	}
	else if (videoFile.match(/\.mp4$/)) {
		document.getElementById("VideoPlaceholder").innerHTML =
			"<embed id=\"FlashMovie\" src=\"640x480.swf?flv=" + videoFile + "\" " +
			"quality=\"high\" pluginspage=\"http://www.macromedia.com/go/getflashplayer\" " +
			"name=\"640x480\" allowscriptaccess=\"sameDomain\" " +
			"type=\"application/x-shockwave-flash\" width=\"640\" height=\"520\"></embed>";
	}
	else if (videoFile.match(/\.swf$/)) {
		document.getElementById("VideoPlaceholder").innerHTML =
			"<embed id=\"FlashMovie\" src=\"" + videoFile + "\" " +
			"quality=\"high\" pluginspage=\"http://www.macromedia.com/go/getflashplayer\" " +
			"name=\"swfplayer\" allowscriptaccess=\"sameDomain\" flashvars=\"autostart=true\" " +
			"type=\"application/x-shockwave-flash\" width=\"640\" height=\"520\"></embed>";
	}
	else
		return true;
	document.getElementById("VideoTitle").innerHTML = videoTitle;
	
	FadeToBlack(0);
	setTimeout("ShowVideoPanel()", 800);

	currentItem = "Video:" + videoFile;
	videoInPlay = true;
	return false;
}

function ShowVideoPanel() {
	var panel = document.getElementById("VideoMask");
	var width = panel.clientWidth;
	var height = panel.clientHeight;

	document.getElementById("VideoPanel").style.left = (width - 654) / 2 + "px";
	document.getElementById("VideoPanel").style.display = "block";
}

function HideVideoPanel() {
	document.getElementById("VideoPanel").style.display = "none";
	document.getElementById("VideoPlaceholder").innerHTML = "";
	document.getElementById("VideoMask").style.display = "none";
	FadeToWhite(80);
}

function StopVideo() {
	document.getElementById("VideoPanel").style.display = "none";
	document.getElementById("VideoPlaceholder").innerHTML = "";
	var layer = document.getElementById("VideoMaskImage");
	layer.style.opacity = "0.0";
	layer.style.filter = "alpha(opacity = 0)";
	document.getElementById("VideoMask").style.display = "none";

	videoInPlay = false;
	return false;
}

function VideoStopped() {
	videoInPlay = false;
	HideVideoPanel();
}

function PlayTutorial(tutorialFile) {
	popupWindow = window.open(tutorialFile, "_blank", "titlebar=yes, location=no, resizable=yes, dependant=yes, " +
		"width=600, height=600, left=" + window.screenLeft + ", top=" + window.screenTop, 1);
	if (popupWindow) {
		popupWindow.focus();
	}
	
	currentItem = "Tutorial:" + tutorialFile;
	tutorialInPlay = true;
	return false;
}

function TutorialStopped() {
	tutorialInPlay = false;
}