var objNavMenu = null;
var prevObjNavMenu = null;
var prevObjDropMenu = null;
var numDropMenu = 2;

////// link styles
var bgLinkColor = "#000";
var bgLinkHover = "#f00";
var bgLinkActive = "#900";
var linkColor = "#fff";
var linkHover = "#fff";
var linkActive = "#fff";
var isIE = null;

if (navigator.appName.indexOf("Microsoft Internet Explorer") != -1) {
	isIE = 1;

}

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

}

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

}

function showDropMenu(e) {

	var menuName = "drop" + this.id.substring(3, this.id.length);
	var objDropMenu = document.getElementById(menuName);

	if (prevObjDropMenu == objDropMenu) {

		hideDropMenu();
		return;

	}

	if (prevObjDropMenu !== null) {

		hideDropMenu();

	}

	objNavMenu = document.getElementById(this.id);

	if ((prevObjNavMenu != objNavMenu) || (prevObjDropMenu === null)) {

		objNavMenu.style.color = linkActive;
		objNavMenu.style.backgroundColor = bgLinkActive;

	}

	if (objDropMenu) {

		var xPos = objNavMenu.offsetParent.offsetLeft + objNavMenu.offsetLeft;
		var yPos = objNavMenu.offsetParent.offsetTop + objNavMenu.offsetParent.offsetHeight;

		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;

}

window.onload = initDropMenu;