var W3CDOM = (document.createElement && document.getElementsByTagName);

var mouseOvers = new Array();
var mouseOuts = new Array();
var j = 0;
var imgs = new Array();
var k = 0;
var a = new Array();

window.onload = init;
function init(){
	if(!W3CDOM) return;
//Create Mouseover image replacement for the main menu
	//Collect images for use in the mouseover
	var imgcoll = document.getElementsByTagName('img');
	for (var LC = 0; LC < imgcoll.length; LC ++){
		if (imgcoll[LC].parentNode.parentNode.className == 'index'){
 		  imgs[j] = imgcoll[LC];
			j = j + 1;
		}
	}
	for (var i=0;i<imgs.length;i++){
   	imgs[i].onmouseover = mouseGoesOver;
	 	imgs[i].onmouseout = mouseGoesOut;
		var suffix = imgs[i].src.substring(imgs[i].src.lastIndexOf('.'));
		mouseOuts[i] = new Image();
		mouseOuts[i].src = imgs[i].src;
		mouseOvers[i] = new Image();
		mouseOvers[i].src = imgs[i].src.substring(0,imgs[i].src.lastIndexOf('.')) + "_hover" + suffix;
		imgs[i].number = i;
	}
//Collect objects for pop outs
	var infoImg = document.getElementById('Information');
	var linkImg = document.getElementById('Links');
	var infoDiv = document.getElementById('infoMenu');
	var linkDiv = document.getElementById('linkMenu');
	infoImg.onmouseover = menuPop;
	infoImg.onmouseout = menuHide;
	linkImg.onmouseover = menuPop;
	linkImg.onmouseout = menuHide;
	infoDiv.onmouseover = menuPop;
	infoDiv.onmouseout = menuHide;
	linkDiv.onmouseover = menuPop;
	linkDiv.onmouseout = menuHide;
	
//Cancel event bubbling on links located in the navigation tab
  var acoll = document.getElementsByTagName('a');
	for (var AC = 0; AC < acoll.length; AC ++){
		if (acoll[AC].parentNode.className == 'index'){
 		  a[k] = acoll[AC];
			k = k + 1;
		}
	}
	for (var i=0;i<imgs.length;i++){
    a[i].onmouseout = navBubble; 
	}
} //close init function

function mouseGoesOver(){
	this.src = mouseOvers[this.number].src;
}

function mouseGoesOut(){
	this.src = mouseOuts[this.number].src;
}
function menuPop(){
	if((this.className == 'infoMenu')||(this.id == 'infoMenu')) {
	var showMenu = document.getElementById('infoMenu');
	var	rootImg = document.getElementById('Information');
	}
	else if((this.className == 'linkMenu') || (this.id == 'linkMenu')){
	  var showMenu = document.getElementById('linkMenu');
		var rootImg = document.getElementById('Links');
	}
	rootImg.src = mouseOvers[rootImg.number].src;
	showMenu.style.visibility = 'visible';
}

function menuHide(e){
	if((this.className == 'infoMenu') || (this.id == 'infoMenu')){
	  var hideMenu = document.getElementById('infoMenu');
		var rootImg = document.getElementById('Information');
	}
	else if((this.className == 'linkMenu') || (this.id == 'linkMenu')){
	  var hideMenu = document.getElementById('linkMenu');
		var rootImg = document.getElementById('Links');
	}
	var relTarg;
	if(!e) var e = window.event;
	if (e.relatedTarget) relTarg = e.relatedTarget;
	else if (e.toElement) relTarg = e.toElement;
	if(!relTarg) return;
	//FROM INFORMATION TO SUBMENU
	if(this.id == 'Information'){
		if(relTarg.id == 'infoMenu') return;
		if(relTarg.parentNode.parentNode.id == 'infoMenu') return;
	}
	//FROM SUBMENU TO INFORMATION
	if(this.id == 'infoMenu' || this.parentNode.parentNode.id == 'infoMenu'){
		if((relTarg.id == 'Information') || (relTarg.id =='infoMenu')) return;
	}
	//FROM LINKS TO SUBMENU
	if(this.id == 'Links'){
		if(relTarg.id == 'linkMenu') return;
		if(relTarg.parentNode.parentNode.id == 'linkMenu') return;
	}	
	//FROM SUBMENU TO LINKS
	if(this.id == 'linkMenu' || this.parentNode.parentNode.id == 'linkMenu'){
		if((relTarg.id == 'Links') || (relTarg.id == 'linkMenu')) return;
	}
	rootImg.src = mouseOuts[rootImg.number].src;
	hideMenu.style.visibility = 'hidden';
} 

function navBubble(e){
  var relTarg;
	if (!e) var e = window.event;
	if (e.relatedTarget) relTarg = e.relatedTarget;
	else if (e.toElement) relTarg = e.toElement;
	if ((!relTarg)||(!relTarg.id)||(relTarg.parentNode.id == 'mainMenu')||(!relTarg.parentNode.id)||(!relTarg.parentNode)) return;
		e.cancelBubble = true;
		if (e.stopPropagation) e.stopPropagation();
}