var currImage = 1;
var totalImages = 21;
var cnt = 0;
var timHandle;
var speed = 10;

version=0
if (navigator.appVersion.indexOf("MSIE")!=-1){
  temp=navigator.appVersion.split("MSIE");
  version=parseFloat(temp[1]);
}

function ChangeImage(n){
	currImage = currImage + n;
	if(currImage>totalImages){ currImage = 1; }
	if(currImage<1){ currImage = totalImages; }
	document.getElementById('essayimage').src = 'images/photoessay_' + currImage + '.jpg';
	UpdateCounter();
	cnt = 0;
	if(n!=0){
		timHandle = window.setTimeout("TransitionMe()", speed);
	}
}

function UpdateCounter(){
	document.getElementById('counter').innerHTML = currImage + ' of ' + totalImages;
}

function TransitionMe(){
	cnt = (cnt+0.02);
	document.getElementById('essayimage').style.filter = 'alpha(opacity=' + (cnt*100) + ')';
	document.getElementById('essayimage').style.MozOpacity = cnt;
	document.getElementById('essayimage').style.opacity = cnt;
	timHandle = window.setTimeout("TransitionMe()", speed);
	if(cnt>=1){
		clearTimeout(timHandle);
	}
}

function SaveCurrentImage(){
  if (version>=5.5){
    win.location.href = 'images/photoessay_' + currImage + '.jpg';
    setTimeout("win.document.execCommand('SaveAs')", 500);
  }
}

function ShowSaveLink(){
	if (version<5.5){
		document.getElementById('saveimg').style.display = 'none';
	} else {
		document.getElementById('saveimg').style.display = 'inline';
	}
}