var objNavMenu = null;
var prevObjNavMenu = null;
var prevObjDropMenu = null;
var numDropMenu = 4;
///// link styles
var bgLinkColor = '#cccccc';
var bgLinkHover = '#ffffff';
var bgLinkActive = '#000000';
var linkColor = '#000000';
var linkHover = '#000000';
var linkActive = '#ffffff';

var isIE = null;		// Internet explorer flag

if (navigator.appName.indexOf('Microsoft Internet Explorer') != -1)
	isIE = 1;
	
	
function initDropMenu() {
		//alert("initDropMenu() 1");

	document.onclick = hideDropMenu;
	for (i=1; i<=numDropMenu;i++){
		menuName = 'dropMenu' + i;
		navName = 'navMenu' + i;
		objDropMenu = document.getElementById(menuName);
		objNavMenu = document.getElementById(navName);
		//alert("initDropMenu() 1 " + navName);
		objDropMenu.style.visibility = 'hidden';
		//objNavMenu.onmouseover = menuHover;
		objNavMenu.onmouseout = menuOut;
		objNavMenu.onmouseover = showDropMenu;
		//objNavMenu.onclick = showDropMenu;
	} 
	objNavMenu = null;
	return;
}

function menuHover (e) {
	//document.onclick = showDropMenu;
	hoverObjNavMenu = document.getElementById(this.id);
	if (hoverObjNavMenu != objNavMenu) {
		hoverObjNavMenu.style.color = linkHover;
		hoverObjNavMenu.style.backgroundColor = bgLinkHover; 
		showDropMenu(e);
	}
	
}

function menuOut () {
	document.onclick = hideDropMenu;
	outObjNavMenu = document.getElementById(this.id);
	if (outObjNavMenu != objNavMenu){
		outObjNavMenu.style.color = linkColor;
		outObjNavMenu.style.backgroundColor = bgLinkColor; 
		hideDropMenu();	
	}
	
}

function showDropMenu(e){
	//alert("showDropMenu(e) 1");
	var xPos = 0;
	var yPos = 0;
	
	menuName = 'drop' + this.id.substring(3,this.id.length);
	menuNumber = this.id.substring(7,this.id.length);
	//alert("menuNumber " + menuNumber);
	objDropMenu = document.getElementById(menuName);
	if (prevObjDropMenu == objDropMenu){
		// if we are still over the previous menu -> do nothing
		//hideDropMenu();
		return;
	}
	//alert("showDropMenu(e) 2");
	//if (prevObjDropMenu != null){
		// hide the previous menu
	hideDropMenu();
	//}
	objNavMenu = document.getElementById(this.id);
	if ((prevObjNavMenu != objNavMenu )
			||
		(prevObjDropMenu == null)){
		// if we have changed menus ---- set new one to the "Active" colors
		objNavMenu.style.color = linkActive;
		objNavMenu.style.backgroundColor = bgLinkActive;
	}
	if(objDropMenu) {
		
		xPos = objNavMenu.offsetParent.offsetLeft + objNavMenu.offsetWidth; 
		yPos = objNavMenu.offsetParent.offsetTop + objNavMenu.offsetTop;
	}
	if (isIE){
		yPos -= 1;
		xPos -= 6;
	}
	
	objDropMenu.style.left = xPos + 'px';
	objDropMenu.style.top = yPos+ 'px';	
	objDropMenu.style.visibility = 'visible';
	prevObjDropMenu = objDropMenu;
	prevObjNavMenu=objNavMenu;
}

function hideDropMenu() {
	document.onclick = null;
	if (prevObjDropMenu){
		prevObjDropMenu.style.visibility = 'hidden';
		prevObjDropMenu = null;
		prevObjNavMenu.style.color = linkColor;
		prevObjNavMenu.style.backgroundColor = bgLinkColor;		
	}
	objNavMenu = null;
	
}