function Browser() {

  var ua, s, i;

  this.isIE    = false;
  this.isNS    = false;
  this.version = null;

  ua = navigator.userAgent;

  s = "MSIE";
  if ((i = ua.indexOf(s)) >= 0) {
    this.isIE = true;
    this.version = parseFloat(ua.substr(i + s.length));
    return;
  }

  s = "Netscape6/";
  if ((i = ua.indexOf(s)) >= 0) {
    this.isNS = true;
    this.version = parseFloat(ua.substr(i + s.length));
    return;
  }

  s = "Gecko";
  if ((i = ua.indexOf(s)) >= 0) {
    this.isNS = true;
    this.version = 6.1;
    return;
  }
}

var browser = new Browser();
var activeButton = null;

addMouseDownListener();

function getContainerWith(node, tagName, className) {
	while (node != null) {
		if (node.tagName != null && node.tagName == tagName && hasClassName(node, className)) {
			return node;
		}
		node = node.parentNode;
	}

	return node;
}

function hasClassName(el, name) {
	var i, list;

	list = el.className.split(" ");
	for (i = 0; i < list.length; i++) {
		if (list[i] == name) {
			return true;
		}
	}
	return false;
}

function removeClassName(el, name) {
	var i, curList, newList;

	if (el.className == null) {
		return;
	}

	newList = new Array();
	curList = el.className.split(" ");
	for (i = 0; i < curList.length; i++) {
		if (curList[i] != name) {
			newList.push(curList[i]);
		}
	}
	el.className = newList.join(" ");
}

function getPageOffsetLeft(el) {
	var x;

	x = el.offsetLeft;
	if (el.offsetParent != null) {
		x += getPageOffsetLeft(el.offsetParent);
	}

	return x;
}

function getPageOffsetTop(el) {
	var y;
	y = el.offsetTop;
	if (el.offsetParent != null) {
		y += getPageOffsetTop(el.offsetParent);
	}
	
	return y;
}

function buttonClick(event, menuId) {
	var button;

	if (browser.isIE) {
		button = window.event.srcElement;
	} else {
		button = event.currentTarget;
	}
	
	button.blur();
	
	if (button.menu == null) {
    	button.menu = document.getElementById(menuId);
	    if (button.menu.isInitialized == null) {
    		menuInit(button.menu);
    	}	
	}
	
	if (activeButton != null) {
		resetButton(activeButton);
	}
	
	if (button != activeButton) {
		depressButton(button);
		activeButton = button;
	} else {
		activeButton = null;
	}

	return false;
}

function buttonMouseover(event, menuId) {
	var button;
	
	if (browser.isIE) {
		button = window.event.srcElement;
	} else {
		button = event.currentTarget;
	}

	if (activeButton != null && activeButton != button) {
		buttonClick(event, menuId);
	}
}

function menuItemMouseover(event, menuId) {
	var item, menu, x, y;

	if (browser.isIE) {
		item = getContainerWith(window.event.srcElement, "A", "menuItem");
	} else {
		item = event.currentTarget;
	}
	menu = getContainerWith(item, "DIV", "menu");

	if (menu.activeItem != null) {
		closeSubMenu(menu);
	}
	menu.activeItem = item;

	item.className += " menuItemActive";

	if (item.subMenu == null) {
		item.subMenu = document.getElementById(menuId);
		if (item.subMenu.isInitialized == null) {
			menuInit(item.subMenu);
		}
	}
	x = getPageOffsetLeft(item) + item.offsetWidth;
	y = getPageOffsetTop(item);

	item.subMenu.style.left = x + "px";
	item.subMenu.style.top  = y + "px";
	item.subMenu.style.visibility = "visible";

	if (browser.isIE) {
		window.event.cancelBubble = true;
	} else {
		event.stopPropagation();
	}
}

function pageMousedown(event) {
	var el;

	if (activeButton == null) {
		return;
	}

	if (browser.isIE) {
    	el = window.event.srcElement;
	} else {
		el = (event.target.tagName ? event.target : event.target.parentNode);
	}

	if (el == activeButton) {
		return;
	}

	if (getContainerWith(el, "DIV", "menu") == null) {
    	resetButton(activeButton);
	    activeButton = null;
	}
}

function addMouseDownListener() {
	if (browser.isIE) {
		document.onmousedown = pageMousedown;
	} else {
		document.addEventListener("mousedown", pageMousedown, true);
	}
}

function depressButton(button) {
	var x, y;

	button.className += " menuButtonActive";

	x = getPageOffsetLeft(button);
	y = getPageOffsetTop(button) + button.offsetHeight;

	button.menu.style.left = x + "px";
	button.menu.style.top  = y + "px";
	button.menu.style.visibility = "visible";
}

function resetButton(button) {
	removeClassName(button, "menuButtonActive");

	if (button.menu != null) {
		closeSubMenu(button.menu);
		button.menu.style.visibility = "hidden";
	}
}

function menuInit(menu) {
	var itemList, spanList;
	var textEl, arrowEl;
	var itemWidth;
	var w, dw;
	var i, j;

	if (browser.isIE) {
	    menu.style.lineHeight = "2.5ex";
	    spanList = menu.getElementsByTagName("SPAN");
	    for (i = 0; i < spanList.length; i++) {
			if (hasClassName(spanList[i], "menuItemArrow")) {
				spanList[i].style.fontFamily = "Webdings";
				spanList[i].firstChild.nodeValue = "4";
			}
	    }  
	}
	
	itemList = menu.getElementsByTagName("A");
	if (itemList.length > 0) {
	    itemWidth = itemList[0].offsetWidth;
	} else {
		return;
	}
	
	for (i = 0; i < itemList.length; i++) {
		spanList = itemList[i].getElementsByTagName("SPAN");
		textEl  = null;
		arrowEl = null;
		for (j = 0; j < spanList.length; j++) {
			if (hasClassName(spanList[j], "menuItemText")) {
		  		textEl = spanList[j];
		  	}	
			if (hasClassName(spanList[j], "menuItemArrow")) {
				arrowEl = spanList[j];
			}
		}	
		if (textEl != null && arrowEl != null) {
		  textEl.style.paddingRight = (itemWidth 
	    	- (textEl.offsetWidth + arrowEl.offsetWidth)) + "px";
	    }
	}
	
	if (browser.isIE) {
		w = itemList[0].offsetWidth;
		itemList[0].style.width = w + "px";
		dw = itemList[0].offsetWidth - w;
		w -= dw;
		itemList[0].style.width = w + "px";
	}
	
	menu.isInitialized = true;
}

function menuMouseover(event) {
	var menu;

	if (browser.isIE) {
		menu = getContainerWith(window.event.srcElement, "DIV", "menu");
	} else {
		menu = event.currentTarget;
	}

	if (menu.activeItem != null) {
		closeSubMenu(menu);
	}
}

function closeSubMenu(menu) {
	if (menu == null || menu.activeItem == null) {
		return;
	}

	if (menu.activeItem.subMenu != null) {
		closeSubMenu(menu.activeItem.subMenu);
		menu.activeItem.subMenu.style.visibility = "hidden";
		menu.activeItem.subMenu = null;
	}
	removeClassName(menu.activeItem, "menuItemActive");
	menu.activeItem = null;
}