// Code to determine the browser and version.

function Browser() {

var ua, s, i;

this.isIE = false; // Internet Explorer
this.isNS = false; // Netscape
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;
}

// Treat any other "Gecko" browser as NS 6.1.

s = "Gecko";
if ((i = ua.indexOf(s)) >= 0) {
this.isNS = true;
this.version = 6.1;
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, "UL", "menu") == null) {
resetButton(activeButton);
activeButton = null;
}
}

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;

return false;
}

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 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";
}

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";
}
}

// Code to handle the menus and sub menus.

function menuMouseover(event) {

var menu;

// Find the target menu element.

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

// Close any active sub menu.

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

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, "LI", "menuItem");
else
item = event.currentTarget;
menu = getContainerWith(item, "UL", "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.isNS) {
maxX = window.scrollX + window.innerWidth;
maxY = window.scrollY + window.innerHeight;
}
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);
}
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";

// Stop the event from bubbling.

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

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("A");
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";
}

// 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)
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;
}