window.onload = DoLoad;
window.onscroll = PositionNavMenu;

function DoLoad()
{
    ShowNavigationDiv();
    ResizePage();
}

// Function to show/hide navigation DIV sections
function ShowNavigationDiv()
{
    var menuName = window.location.href.toLowerCase();
    var subMenuName;
    
    menuName = menuName.substring(menuName.replace("\\", "/").lastIndexOf("/") + 1);
    if (menuName.indexOf(".") != -1) menuName = menuName.substring(0, menuName.indexOf("."));
    subMenuName = "navsub_" + menuName;
    menuName = "nav_" + menuName;
    
    // Show selected page's sub-menu and highlight menu item
    if (document.getElementById(subMenuName)) document.getElementById(subMenuName).style.display = '';
    if (document.getElementById(menuName)) 
    {
        document.getElementById(menuName).style.color = "white";
        document.getElementById(menuName).style.backgroundColor = "#4F8400";
    }
}

// Function to resize the page to a standard minimum height
function ResizePage()
{
    var bannerHeight = document.getElementById("BannerContainer").offsetHeight;
    var footerHeight = document.getElementById("FooterContainer").offsetHeight;
    var contentHeight = document.getElementById("ContentContainer").scrollHeight;
    var minContentHeight = (document.body.scrollHeight - bannerHeight - footerHeight - 20);
    if (IsOlderIEVersion()) minContentHeight = document.body.scrollHeight - document.getElementById("ContentContainer").offsetTop;

    // Resize content wrapper
    if (contentHeight < minContentHeight)
        document.getElementById("ContentContainer").style.height = minContentHeight + "px";
        
    // Set content to same height as wrapper
    document.getElementById("Content").style.height = document.getElementById("ContentContainer").offsetHeight + "px";
    
    // Resize page (for footer spacing)
    document.getElementById("Page").style.height = (bannerHeight + contentHeight + footerHeight + 10) + "px";
}

function ScrollPage(evt, anchorName)
{
    // Event pointer
    var e = (evt ? evt : window.event);
    
    // Scroll to named anchor
    var anchors = document.getElementsByName(anchorName);
    if (!anchors) return;
    var anchor = anchors[0]; 
    var scroll = anchor.offsetTop;
    if (IsOlderIEVersion()) scroll += document.getElementById("ContentContainer").offsetTop + 5;
    
    window.scrollTo(0, scroll);
    
    // Avoid bubbling to parent element
    e.cancelBubble = true;
}

// PositionNavMenu - Changes position with relative values if less than IE8
function PositionNavMenu()
{
    var bannerHeight = document.getElementById("BannerContainer").offsetHeight;
    
    if (document.documentElement.scrollTop > bannerHeight)
    {
        document.getElementById("Navigation").style.position = "fixed";
        document.getElementById("Navigation").style.top = 0;
        
        if (IsOlderIEVersion())
        {
            document.getElementById("Navigation").style.position = "relative";
            document.getElementById("Navigation").style.top = document.documentElement.scrollTop - document.getElementById("ContentContainer").offsetTop;
            document.getElementById("Navigation").style.left = "0px";
        }
    }
    else
        document.getElementById("Navigation").style.position = "static";       
}

function IsOlderIEVersion() 
{    
    var olderIE = false;
    
    if (navigator && navigator.appName == 'Microsoft Internet Explorer') 
    {        
        var ua = navigator.userAgent;        
        var re = new RegExp("MSIE ([0-9]{1,}[\.0-9]{0,})");        
        if (re.exec(ua) != null)            
            olderIE = (parseFloat(RegExp.$1) < 8.0);
        else
            olderIE = true;    
    }    
    return olderIE;
}