/* Fisheye Menu v1.0 
   Written by Marc Grabanski (m@marcgrabanski.com)

   Copyright (c) 2007 Marc Grabanski (http://marcgrabanski.com/code/fisheye-menu)
   Dual licensed under the GPL (http://www.gnu.org/licenses/gpl-3.0.txt) and 
   CC (http://creativecommons.org/licenses/by/3.0/) licenses. "Share or Remix it but please Attribute the authors."
   Date: 10-05-2007  */

var fisheyemenu = {
	startSize : 32,
	endSize : 48,
	imgType : ".png",
	init : function () {
		var animElements = document.getElementById("fisheye_menu").getElementsByTagName("img");
		var titleElements = document.getElementById("fisheye_menu").getElementsByTagName("span");
		for(var i=0; i<animElements.length; i++) {
			var y = animElements[i];
			y.style.width = fisheyemenu.startSize+'px';
			y.style.height = fisheyemenu.startSize+'px';
			animElements[i].onmouseover = changeSize;
			animElements[i].onmouseout = restoreSize;
		}
		function changeSize() {
			fisheyemenu.imgLarge(this);
			var x = this.parentNode.getElementsByTagName("span");
			x[0].style.display = 'block';
			if (!this.currentWidth) this.currentWidth = fisheyemenu.startSize;
			fisheyemenu.resizeAnimation(this,this.currentWidth,fisheyemenu.endSize,15,10,0.333);
		}
		function restoreSize() {
			var x = this.parentNode.getElementsByTagName("span");
			x[0].style.display = 'none';
			if (!this.currentWidth) return;
			fisheyemenu.resizeAnimation(this,this.currentWidth,fisheyemenu.startSize,15,10,0.5);
			fisheyemenu.imgSmall(this);
		}
	},
	resizeAnimation : function (elem,startWidth,endWidth,steps,intervals,powr) {
		if (elem.widthChangeMemInt) window.clearInterval(elem.widthChangeMemInt);
		var actStep = 0;
		elem.widthChangeMemInt = window.setInterval(
			function() {
				elem.currentWidth = fisheyemenu.easeInOut(startWidth,endWidth,steps,actStep,powr);
				elem.style.width = elem.currentWidth+"px";
				elem.style.height = elem.currentWidth+"px";
				actStep++;
				if (actStep > steps) window.clearInterval(elem.widthChangeMemInt);
			}
			,intervals)
	},
	easeInOut : function (minValue,maxValue,totalSteps,actualStep,powr) {
	//Generic Animation Step Value Generator By www.hesido.com
		var delta = maxValue - minValue;
		var stepp = minValue+(Math.pow(((1 / totalSteps)*actualStep),powr)*delta);
		return Math.ceil(stepp)
	},
	imgSmall : function (obj) {
		imgSrc = obj.getAttribute("src");
		var typePos = imgSrc.indexOf(fisheyemenu.imgType, 0);
		var imgName = imgSrc.substr(0, typePos);
		obj.setAttribute("src", imgName+"_small"+fisheyemenu.imgType);
	},
	imgLarge : function (obj) {
		imgSrc = obj.getAttribute("src");
		var typePos = imgSrc.indexOf("_small", 0);
		var imgName = imgSrc.substr(0, typePos);
		obj.setAttribute("src", imgName+fisheyemenu.imgType);
	}
}

// Add event with wide browser support
if ( typeof window.addEventListener != "undefined" )
    window.addEventListener( "load", fisheyemenu.init, false );
else if ( typeof window.attachEvent != "undefined" )
    window.attachEvent( "onload", fisheyemenu.init );
else {
    if ( window.onload != null ) {
        var oldOnload = window.onload;
        window.onload = function ( e ) {
            oldOnload( e );
            fisheyemenu.init();
        };
    }
    else
        window.onload = fisheyemenu.init;
}