function ImageExpander(oThumb, sImgSrc) {
	this.oThumb = oThumb;
	this.oThumb.expander = this;
	this.oThumb.onclick = function() { this.expander.expand(); }
	
	this.smallWidth = oThumb.offsetWidth;
	this.smallHeight = oThumb.offsetHeight;	

	this.bExpand = true;
	this.bTicks = false;
	
	if (!window.aImageExpanders) {
		window.aImageExpanders = new Array();
	}
	window.aImageExpanders.push(this);

	this.oImg = new Image();
	this.oImg.expander = this;
	this.oImg.onload = function(){this.expander.onload();}
	this.oImg.src = sImgSrc;
}

ImageExpander.prototype.onload = function() {
	this.oDiv = document.createElement("div");
	document.body.appendChild(this.oDiv);
	this.oDiv.appendChild(this.oImg);
	this.oDiv.style.position = "absolute";
	this.oDiv.style.zIndex = 999999999;
	this.oDiv.expander = this;
	this.oDiv.onclick = function() {this.expander.toggle();};
	this.oImg.title = "Click to reduce.";
	this.bigWidth = this.oImg.width;
	this.bigHeight = this.oImg.height;
	
	if (this.bExpand) {
		this.expand();
	} else {
		this.oDiv.style.visibility = "hidden";
		this.oImg.style.visibility = "hidden";
	}
}
ImageExpander.prototype.toggle = function() {
	this.bExpand = !this.bExpand;
	if ( this.bExpand ) {
		for ( var i in window.aImageExpanders )
			if ( window.aImageExpanders[i] !== this )
				window.aImageExpanders[i].reduce();
	}
}
ImageExpander.prototype.expand = function() {
	this.bExpand = true;

	for ( var i in window.aImageExpanders )
		if ( window.aImageExpanders[i] !== this )
			window.aImageExpanders[i].reduce();

	if ( !this.oDiv ) return;
	
	this.oThumb.style.visibility = "hidden";
	
	this.x = this.oThumb.offsetLeft;
	this.y = this.oThumb.offsetTop;
	this.w = this.oThumb.clientWidth;
	this.h = this.oThumb.clientHeight;
	
	this.oDiv.style.left = this.x + "px";
	this.oDiv.style.top = this.y + "px";
	this.oImg.style.width = this.w + "px";
	this.oImg.style.height = this.h + "px";
	this.oDiv.style.visibility = "visible";
	this.oImg.style.visibility = "visible";
	
	if (!this.bTicks) {
		this.bTicks = true;
		var pThis = this;
		window.setTimeout(function(){pThis.tick();},25);	
	}
}
ImageExpander.prototype.reduce = function() {
	this.bExpand = false;
}
ImageExpander.prototype.tick = function() {
	var cw = document.body.clientWidth;
	var ch = document.body.clientHeight;
	var cx = 400;
	var cy = document.body.scrollTop + ch / 2;

	var tw,th,tx,ty;
	if (this.bExpand) {
		tw = this.bigWidth;
		th = this.bigHeight;
		if (tw > cw) {
			th *= cw / tw;
			tw = cw;
		}	
		if (th > ch) {
			tw *= ch / th;
			th = ch;
		}
		tx = cx - tw / 2;
		ty = cy - th / 2; 
	} else {
		tw = this.smallWidth;
		th = this.smallHeight;
		tx = this.oThumb.offsetLeft;
		ty = this.oThumb.offsetTop;
	}
	var nHit = 0;
	var fMove = function(n,tn) {
		var dn = tn - n;
		if ( Math.abs(dn) < 3 ) {
			nHit++;
			return tn;
		} else {
			return n + dn / 5;
		}
	}
	this.x = fMove(this.x, tx);
	this.y = fMove(this.y, ty);
	this.w = fMove(this.w, tw);
	this.h = fMove(this.h, th);
	
	this.oDiv.style.left = this.x + "px";
	this.oDiv.style.top = this.y + "px";
	this.oImg.style.width = this.w + "px";
	this.oImg.style.height = this.h + "px";

	if (!this.bExpand && (nHit == 4)) {
		this.oImg.style.visibility = "hidden";
		this.oDiv.style.visibility = "hidden";
		this.oThumb.style.visibility = "visible";

		this.bTicks = false;
	}
	
	if ( this.bTicks ) {
		var pThis = this;
		window.setTimeout(function(){pThis.tick();},25);
	}
}