function Browser() {

	var ua, s, i;
	
	this.isIE    = false;  // Internet Explorer
	this.isOP    = false;  // Opera
	this.isNS    = false;  // Netscape
	this.version = null;
	
	ua = navigator.userAgent;
	
	s = "Opera";
	if ((i = ua.indexOf(s)) >= 0) {
		this.isOP = 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;
	}

	// Treat any other "Gecko" browser as Netscape 6.1.
	s = "Gecko";
	if ((i = ua.indexOf(s)) >= 0) {
		this.isNS = true;
		this.version = 6.1;
		return;
	}

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

function getContainerWith(node, tagName, className) {
	// Starting with the given node, find the nearest containing element
	// with the specified tag name and style class.
	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;
	
	// Return true if the given element currently has the given class
	// name.
	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;
	
	// Remove the given class name from the element's className property.
	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;
	// Return the x coordinate of an element relative to the page.
	x = el.offsetLeft;
	if (el.offsetParent != null){
		x += getPageOffsetLeft(el.offsetParent);
	}
	return x;
}

function getPageOffsetTop(el) {
	var y;

	// Return the x coordinate of an element relative to the page.
	y = el.offsetTop;
	if (el.offsetParent != null){
		y += getPageOffsetTop(el.offsetParent);
	}
	return y;
}

function buttonClick(event, menuId) {
	var button;

	// Get the target button element.
	if (browser.isIE) {
		button = window.event.srcElement;
	} else {
		button = event.currentTarget;
	}

	// Blur focus from the link to remove that annoying outline.
	button.blur();

	// Associate the named menu to this button if not already done.
	// Additionally, initialize menu display.
	if (button.menu == null) {
		button.menu = document.getElementById(menuId);
		if (button.menu.isInitialized == null){
			menuInit(button.menu);
		}
	}

	// Reset the currently active button, if any.
	if (activeButton != null){
		resetButton(activeButton);
	}

	// Activate this button, unless it was the currently active one.
	if (button != activeButton) {
		depressButton(button);
		activeButton = button;
	} else {
		activeButton = null;
	}
	
	//So the browser doesn't try to follow the link
	return false;
}

function depressButton(button) {
	var x, y;
	
	// Update the button's style class to make it look like it's
	// depressed.
	button.className += " menuButtonActive";
	
	// Position the associated drop down menu under the button and
	// show it.
	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";

	// For IE; size, position and show the menu's IFRAME as well.
	if (button.menu.iframeEl != null){
		button.menu.iframeEl.style.left = button.menu.style.left;
		button.menu.iframeEl.style.top  = button.menu.style.top;
		button.menu.iframeEl.style.width  = button.menu.offsetWidth + "px";
		button.menu.iframeEl.style.height = button.menu.offsetHeight + "px";
		button.menu.iframeEl.style.display = "";
	}
}

function resetButton(button) {
	// Restore the button's style class.
	removeClassName(button, "menuButtonActive");
	
	// Hide the button's menu, first closing any sub menus.
	if (button.menu != null) {
		closeSubMenu(button.menu);
		button.menu.style.visibility = "hidden";

		// For IE, hide menu's IFRAME as well.
	    if (button.menu.iframeEl != null){
			button.menu.iframeEl.style.display = "none";
		}
	}
}

function buttonMouseover(event, menuId) {
	var button;

	// Find the target button element.
	if (browser.isIE){
		button = window.event.srcElement;
	} else {
		button = event.currentTarget;
	}
	
	// If any other button menu is active, make this one active instead.
	if (activeButton != null && activeButton != button){
		buttonClick(event, menuId);
	}
}

function pageMousedown(event) {
	var el;
	
	// If there is no active button, exit.
	if (activeButton == null)
		return;

	// Find the element that was clicked on.
	if (browser.isIE) {
		el = window.event.srcElement;
	} else {
		el = (event.target.tagName ? event.target : event.target.parentNode);
	}
	
	// If the active button was clicked on, exit.
	if (el == activeButton)
		return;

	// If the element is not part of a menu, reset and clear the active
	// button.
	if (getContainerWith(el, "DIV", "menu") == null) {
		resetButton(activeButton);
		activeButton = null;
	}
}

function closeSubMenu(menu) {
	
	if (menu == null || menu.activeItem == null)
		return;
	
	// Recursively close any sub menus.
	if (menu.activeItem.subMenu != null) {
		closeSubMenu(menu.activeItem.subMenu);
		menu.activeItem.subMenu.style.visibility = "hidden";
	
		// For IE, hide the sub menu's IFRAME as well.
		if (menu.activeItem.subMenu.iframeEl != null){
			menu.activeItem.subMenu.iframeEl.style.display = "none";
		}
		
		menu.activeItem.subMenu = null;
	}

	// Deactivate the active menu item.
	removeClassName(menu.activeItem, "menuItemHighlight");
	menu.activeItem = null;
}

function menuInit(menu) {
	var itemList, spanList;
	var textEl, arrowEl;
	var itemWidth;
	var w, dw;
	var i, j;
	
	// For IE, replace arrow characters.
	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";
			}
		}
	}
	
	// Find the width of a menu item.
	itemList = menu.getElementsByTagName("A");
	if (itemList.length > 0){
		itemWidth = itemList[0].offsetWidth;
	} else {
		return;
	}

	// For items with arrows, add padding to item text to make the
	// arrows flush right.
	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") || hasClassName(spanList[j], "menuItemDisabled")){
				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";
			// For Opera, remove the negative right margin to fix a display bug.
			if (browser.isOP){
				arrowEl.style.marginRight = "0px";
			}
		}
	}

	// Fix IE hover problem by setting an explicit width on first item of
	// the menu.
	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";
	}

	// Fix the IE display problem (SELECT elements and other windowed controls
	// overlaying the menu) by adding an IFRAME under the menu.
	if (browser.isIE) {
		var iframeEl = document.createElement("IFRAME");
		iframeEl.frameBorder = 0;
		iframeEl.src = "javascript:;";
		iframeEl.style.display = "none";
		iframeEl.style.position = "absolute";
		iframeEl.style.filter = "progid:DXImageTransform.Microsoft.Alpha(style=0,opacity=0)";
		menu.iframeEl = menu.parentNode.insertBefore(iframeEl, menu);
	}

	// Mark menu as initialized.
	menu.isInitialized = true;
}

function menuItemMouseover(event, menuId) {
	var item, menu, x, y;
	
	// Find the target item element and its parent menu element.
	if (browser.isIE){
		item = getContainerWith(window.event.srcElement, "A", "menuItem");
	} else {
		item = event.currentTarget;
	}
	menu = getContainerWith(item, "DIV", "menu");

	// Close any active sub menu and mark this one as active.
	if (menu.activeItem != null){
		closeSubMenu(menu);
	}
	menu.activeItem = item;

	// Highlight the item element.
	item.className += " menuItemHighlight";

	// Initialize the sub menu, if not already done.
	if (item.subMenu == null) {
		item.subMenu = document.getElementById(menuId);
		if (item.subMenu.isInitialized == null){
			menuInit(item.subMenu);
		}
	}

	// Get position for submenu based on the menu item.
	x = getPageOffsetLeft(item) + item.offsetWidth;
	y = getPageOffsetTop(item);

	// Adjust position to fit in view.
	var maxX, maxY;
	if (browser.isIE) {
		maxX = (document.documentElement.scrollLeft   != 0 ?
		         document.documentElement.scrollLeft
				 : document.body.scrollLeft)
				 + (document.documentElement.clientWidth  != 0 ?
				 document.documentElement.clientWidth
				 : document.body.clientWidth);
		maxY = (document.documentElement.scrollTop    != 0 ?
				document.documentElement.scrollTop 
				: document.body.scrollTop)
				+ (document.documentElement.clientHeight != 0 ?
				document.documentElement.clientHeight
				: document.body.clientHeight);
	}
	
	if (browser.isOP) {
		maxX = document.documentElement.scrollLeft + window.innerWidth;
		maxY = document.documentElement.scrollTop  + window.innerHeight;
	}
	
	if (browser.isNS) {
		maxX = window.scrollX + window.innerWidth;
		maxY = window.scrollY + window.innerHeight;
	}
	
	maxX -= item.subMenu.offsetWidth;
	maxY -= item.subMenu.offsetHeight;
	
	if (x > maxX){
		x = Math.max(0, x - item.offsetWidth - item.subMenu.offsetWidth 
			+ (menu.offsetWidth - item.offsetWidth));
	}
	y = Math.max(0, Math.min(y, maxY));

	// Position and show it.
	item.subMenu.style.left = x + "px";
	item.subMenu.style.top  = y + "px";
	item.subMenu.style.visibility = "visible";

	// For IE; size, position and show the menu's IFRAME as well.
	if (item.subMenu.iframeEl != null){
		item.subMenu.iframeEl.style.left    = item.subMenu.style.left;
		item.subMenu.iframeEl.style.top     = item.subMenu.style.top;
		item.subMenu.iframeEl.style.width   = item.subMenu.offsetWidth + "px";
		item.subMenu.iframeEl.style.height  = item.subMenu.offsetHeight + "px";
		item.subMenu.iframeEl.style.display = "";
	}

	// Stop the event from bubbling.
	if (browser.isIE){
		window.event.cancelBubble = true;
	} else {
		event.stopPropagation();
	}
}

function menuMouseover(event) {
	var menu;
	
	// Find the target menu element.
	if (browser.isIE){
		menu = getContainerWith(window.event.srcElement, "DIV", "menu");
	} else {
		menu = event.currentTarget;
	}
	
	// Close any active sub menu.
	if (menu.activeItem != null){
		closeSubMenu(menu);
	}
}

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

	// Recursively close any sub menus.
	if (menu.activeItem.subMenu != null) {
		closeSubMenu(menu.activeItem.subMenu);
		menu.activeItem.subMenu.style.visibility = "hidden";
		menu.activeItem.subMenu = null;
	}
	removeClassName(menu.activeItem, "menuItemHighlight");
	menu.activeItem = null;
}


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

// Capture mouse clicks on the page so any active button can be
// deactivated.
if (browser.isIE){
	document.onmousedown = pageMousedown;
} else {
	document.addEventListener("mousedown", pageMousedown, true);
}