/***************************************************************************************
** DATE:		08.31.04
** TEMPLATE:	Scripts/MenuScripts
** DESCRIPTION:	Scripts to cause the dropdown menu for the main site.          
** METHODS: 	
** ATTRIBUTE:	
** NOTES:		
** CALLED BY:	Homesite/Index
** INCLUDES:	
***************************************************************************************/

/******************************************************************************
// Code to determine the browser and version.
******************************************************************************/
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;
	}
}

var browser = new Browser();

/******************************************************************************
// Code for handling the menu bar and active button.
******************************************************************************/
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);

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;
	}
}


/******************************************************************************
/* On mouseover, function is called
******************************************************************************/
function MenuMouseOver(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;
}

/******************************************************************************
/* Display dropdown menu
******************************************************************************/
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;
	// For IE, adjust position.
	if (browser.isIE) {
		x += button.offsetParent.clientLeft;
		y += button.offsetParent.clientTop;
	}
	
	button.menu.style.left = x + "px";
	button.menu.style.top  = y + "px";
	button.menu.style.visibility = "visible";
}

/******************************************************************************
/* Reset all buttons
******************************************************************************/
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";
	}
}

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;
}

/******************************************************************************
// Code to initialize menus.
******************************************************************************/
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"))
				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";
	}
	// Mark menu as initialized.
	menu.isInitialized = true;
}

/******************************************************************************
// General utility functions.
******************************************************************************/
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 && curList[i].length != 0){
			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;
}