var curImg = 0;
var timerId = -1;
var intervalf = 3000;
var intervalm = 4500;
var intervals = 6000;
var interval = intervalm;
var imgIsLoaded = false;

function replaceNum(myinput, token, newstr)
{
	var input = myinput;
	var output = input;
	var idx = output.indexOf(token);
	if (idx > -1)
	{
		output = input.substring(0, idx);
		output += newstr;
		output += input.substr(idx+token.length);
	}
	return output;
}

function changeSpeed(sidx)
{
	switch (sidx)
	{
		case 0: interval = intervalm; break;
		case 1: interval = intervals; break;
		default: interval = intervalf;
	}
	if (timerId != -1)
	{
		window.clearInterval(timerId);
		timerId = window.setInterval("forward();", interval);
	}
}

function imgLoadNotify()
{
	imgIsLoaded = true;
}

function changeSlide()
{
	if (document.all)
	{	
		//transition [0..23]
		document.all.imgp.style.filter="revealTrans(duration=3,transition=8)";
		document.all.imgp.filters[0].Apply(); 		
	}	
	imgIsLoaded = false;
	var htmlCont = "<center>" +
		"<img src=\"" + imageSrcArray[curImg] + "\" alt=\"" + imageNameArray[curImg] + "\"";
	if (imageWidthArray[curImg] > 0 && imageHeightArray[curImg] > 0)
	{
		htmlCont += " width=" + imageWidthArray[curImg] + " height=" + imageHeightArray[curImg];
	}	
	htmlCont += " border=0 onload=\"javascript: imgLoadNotify();\">";
	htmlCont += "<small>" + imageDescArray[curImg] + "</small></center>";
	htmlImg = "<center><br><span class=Text_Main>" + imageNameArray[curImg] + "</span><br></center>"
	var pnumLine = "<small>";
	pnumLine += replaceNum(SHOWINGSTRING, "%slideNum", eval(curImg+1));
	pnumLine += "</small>";	
	if (document.layers)	
	{		
		document.layers[1].document.imgDiv.document.open();
		document.layers[1].document.imgDiv.document.write(htmlCont);
		document.layers[1].document.imgDiv.document.close();

		document.layers[0].document.layers[0].document.open();
		document.layers[0].document.layers[0].document.write(pnumLine);
		document.layers[0].document.layers[0].document.close();
	}
	else
	{
		document.getElementById("pem").innerHTML = pnumLine;		
		document.getElementById("imgp").innerHTML = htmlCont;
		document.getElementById("TenAnh").innerHTML = htmlImg;		
	}	
	if (document.all) 
	{
		document.all.imgp.filters[0].Play();
	}
}

function forward()
{
	if (imgIsLoaded)
	{
		curImg++;
		if (curImg == numImgs)
			curImg = 0;
		changeSlide();
	}
}

function rewind()
{
	curImg--;
	if (curImg < 0)
		curImg = numImgs - 1;
	changeSlide();
}

function stop()
{
	window.clearInterval(timerId);
	timerId = -1;
	document.playbtn.src = buttonImgPfx + buttonOffArray[0];
	document.stopbtn.src = buttonImgPfx + buttonOnArray[1];
	imgIsLoaded = true;
}

function play()
{
	if (timerId == -1) timerId = window.setInterval('javascript: forward();', interval);
	document.playbtn.src = buttonImgPfx + buttonOnArray[0];
	document.stopbtn.src = buttonImgPfx + buttonOffArray[1];
}

function setButton(direction)
{
	imgIsLoaded = true;
	if (direction == 0)
	{
		document.prevbtn.src = buttonImgPfx + buttonOnArray[2];
		window.setTimeout("javascript:document.prevbtn.src = buttonImgPfx + buttonOffArray[2];", 300);
	}
	else
	{
		document.fowdbtn.src = buttonImgPfx + buttonOnArray[3];
		window.setTimeout("javascript:document.fowdbtn.src = buttonImgPfx + buttonOffArray[3];", 300);
	}
}