var isDOM = (document.getElementById ? true : false); 
var isIE4 = ((document.all && !isDOM) ? true : false);
var isNS4 = (document.layers ? true : false);


// Hide timeout.
var popTimer = 0;

// Array showing highlighted menu items.
var litNow = new Array();


function getRef(id) 
{
    if (isDOM) 
        return( document.getElementById(id) );
    if (isIE4) 
        return( document.all[id] );
    if (isNS4) 
        return( document.layers[id] );
}

function getSty(id)
{
    return( isNS4 ? getRef(id) : getRef(id).style );
} 

function popOver( menuNum, itemNum )
{
    clearTimeout( popTimer );
    hideAllBut( menuNum );
    litNow = getTree( menuNum, itemNum );
    changeCol( litNow, true );
    targetNum = menu[ menuNum ][ itemNum ].target;
    
    if(targetNum > 0)
    {
        thisX = parseInt( menu[ menuNum ][0].ref.left ) + parseInt( menu[ menuNum ][ itemNum ].ref.left );
        thisY = parseInt( menu[ menuNum ][0].ref.top  ) + parseInt( menu[ menuNum ][ itemNum ].ref.top  );
        
        with( menu[ targetNum ][ 0 ].ref )
        {
            left = parseInt( thisX + menu[ targetNum ][ 0 ].x);
            top  = parseInt( thisY + menu[ targetNum ][ 0 ].y);
            visibility = 'visible';
        }
    }
}


function popOut( menuNum, itemNum )
{
    if( ( menuNum == 0 ) && !menu[ menuNum ][ itemNum ].target )
        hideAllBut(0)
    else
        popTimer = setTimeout( 'hideAllBut(0)', 500 );
}

function getTree( menuNum, itemNum )
{

    // Array index is the menu number. The contents are null (if that menu is not a parent)
    // or the item number in that menu that is an ancestor (to light it up).
    itemArray = new Array( menu.length );

    while( 1 )
    {
        itemArray[ menuNum ] = itemNum;

        // If we've reached the top of the hierarchy, return.
        if( menuNum == 0 )
            return itemArray;

        itemNum = menu[ menuNum ][ 0 ].parentItem;
        menuNum = menu[ menuNum ][ 0 ].parentMenu;
   }
}

// Pass an array and a boolean to specify colour change, true = over colour.
function changeCol( changeArray, isOver )
{
    for( menuCount = 0; menuCount < changeArray.length; menuCount++ )
    {
        if( changeArray[ menuCount ] )
        {
            newimage = isOver ? menu[menuCount][changeArray[menuCount]].litimage : menu[menuCount][changeArray[menuCount]].image;

            if (isDOM || isIE4) 
                document[ menu[menuCount][changeArray[menuCount]].classid ].src = newimage;
            if (isNS4) 
                menu[menuCount][changeArray[menuCount]].ref.document.images[ 0 ].src = newimage;
        } 
    }
}


function hideAllBut( menuNum )
{
    var keepMenus = getTree( menuNum, 1 );

    for( count = 0; count < menu.length; count++ )
        if( !keepMenus[ count ] )
            menu[ count ][ 0 ].ref.visibility = 'hidden';

    changeCol( litNow, false );
}

// *** MENU CONSTRUCTION FUNCTIONS ***

function Menu( isVert, x, y, width, backCol )
{
    // True or false - a vertical menu?
    this.isVert = isVert;

    // Position and size settings.
    this.x = x;
    this.y = y;
    this.width = width;

    // Colours of menu
    this.backCol = backCol;

    // Parent menu and item numbers, indexed later.
    this.parentMenu = null;
    this.parentItem = null;

    // Reference to the object's style properties (set later).
    this.ref = null;
}

function Item( text, image, litimage, href, frame, length, spacing, target, bitmapwidth, classid )
{
    this.text = text;
    this.image = image;
    this.litimage = litimage;
    this.href = href;
    this.frame = frame;
    this.length = length;
    this.spacing = spacing;
    this.target = target;
    this.bitmapwidth = bitmapwidth
    this.classid = classid;
    this.preloadimagemain = new Image();
    this.preloadimagemain.src = image;
    this.preloadimagelit = new Image();
    this.preloadimagelit.src = litimage;

    // Reference to the object's style properties (set later).
    this.ref = null;
}


function writeMenus()
{
    if( !isDOM && !isIE4 && !isNS4 ) 
        return;

    for( currMenu = 0; currMenu < menu.length; currMenu++ ) 
    with( menu[ currMenu ][ 0 ] ) 
    {
        // Variable for holding HTML for items and positions of next item.
        var str = '', itemX = 0, itemY = 0;

        // Remember, items start from 1 in the array (0 is menu object itself, above).
        // Also use properties of each item nested in the other with() for construction.
        for( currItem = 1; currItem < menu[ currMenu ].length; currItem++ )
        with( menu[ currMenu ][ currItem ] ) 
        {
            var itemID = 'menu' + currMenu + 'item' + currItem;

            // The width and height of the menu item - dependent on orientation!
            var w = ( isVert ? width : length );
            var h = ( isVert ? length : width );

            // Create a div or layer text string with appropriate styles/properties.
            // Thanks to Paul Maden (www.paulmaden.com) for helping debug this in IE4, apparently
            // the width must be a miniumum of 3 for it to work in that browser.
            if( isDOM || isIE4 ) 
            {
                str += '<div id="' + itemID + '" style="position: absolute; left: ' + itemX + '; top: ' + itemY + '; width: ' + w + '; height: ' + h + '; visibility: inherit; ';
                if( backCol ) 
                    str += 'background: ' + backCol + '; ';
                str += '" ';
            }

            if( isNS4 )
            {
                str += '<layer id="' + itemID + '" left="' + itemX + '" top="' + itemY + '" width="' +  w + '" height="' + h + '" visibility="inherit" ';
        
                if( backCol )
                    str += 'bgcolor="' + backCol + '" ';
            }

            // Add mouseover handlers and finish div/layer.
            str += 'onMouseOver="popOver(' + currMenu + ',' + currItem + ')" onMouseOut="popOut(' + currMenu + ',' + currItem + ')">';

            // Add contents of item (default: table with link inside).
            // In IE/NS6+, add padding if there's a border to emulate NS4's layer padding.
            // If a target frame is specified, also add that to the <a> tag.

            if( href )
            {
                str += '<table width="' + w + '" border="0" cellspacing="0" cellpadding="0"><tr><td align="left" height="' + h + '">' + '<a href="' + href + '"' + (frame ? ' target="' + frame + '">' : '>') + '<IMG border="0" name= "' + classid + '" src="' + image + '" alt="' + text + '" width="' + bitmapwidth + '" height="' + h + '"20">' + '</a></td>';
            }
            else
            {
                str += '<table width="' + w + '" border="0" cellspacing="0" cellpadding="0"><tr><td align="left" height="' + h + '">' + '<IMG border="0" name= "' + classid + '" src="' + image + '" alt="' + text + '" width="' + bitmapwidth + '" height="' + h + '"20">' + '</td>';
            }
            

            if (target > 0) 
            {
                // Set target's parents to this menu item.
                menu[target][0].parentMenu = currMenu;
                menu[target][0].parentItem = currItem;
            }


            str += '</tr></table>' + (isNS4 ? '</layer>' : '</div>');
        
            if (isVert) 
                itemY += length + spacing;
            else 
                itemX += length + spacing;
        }

        if (isDOM) 
        {
            var newDiv = document.createElement('div');
            document.getElementsByTagName('body').item(0).appendChild(newDiv);
            newDiv.innerHTML = str;
            ref = newDiv.style;
            ref.position = 'absolute';
            ref.visibility = 'hidden';
        }

        // Insert a div tag to the end of the BODY with menu HTML in place for IE4.
        if (isIE4) 
        {
            document.body.insertAdjacentHTML('beforeEnd', '<div id="menu' + currMenu + 'div" ' + 'style="position: absolute; visibility: hidden">' + str + '</div>');
            ref = getSty('menu' + currMenu + 'div');
        }

        // In NS4, create a reference to a new layer and write the items to it.
        if (isNS4) 
        {
            ref = new Layer(0);
            ref.document.write(str);
            ref.document.close();
        }   

        for (currItem = 1; currItem < menu[currMenu].length; currItem++) 
        {
            itemName = 'menu' + currMenu + 'item' + currItem;

            if (isDOM || isIE4) 
                menu[currMenu][currItem].ref = getSty(itemName);
            if (isNS4) 
                menu[currMenu][currItem].ref = ref.document[itemName];
        }
    }

    with(menu[0][0])
    {
        ref.left = x;
        ref.top = y;
        ref.visibility = 'visible';
    }
}


var menu = new Array();
menu[0] = new Array();
// Default colours passed to most menu constructors (just passed to functions, not
// a global variable - makes things easier to change later in bulk).
var defBack = '#cccccc';

// Default 'length' of menu items - item height if menu is vertical, width if horizontal.
var defLength = 20;

// Main menu 
menu[0] = new Array();
menu[0][0] = new Menu( false, 0, 81, 20, '#5169e0', '#5169e0' );
//                     Alt Text            Standard Image           Lit Image                  Link   Frame  Width Space Menu  Width  Class Name
menu[0][1] = new Item(  'Home',        'images/menuhome.gif',      'images/menuhomelit.gif',      'default.htm',   '',   154,   0,   0,   154,  'menuhome'      );
menu[0][2] = new Item(  'Guests',      'images/menuguests.gif',    'images/menuguestslit.gif',    '',   '',   154,   0,   1,   154,  'menuguests'    );
menu[0][3] = new Item(  'Resources',   'images/menuresources.gif', 'images/menuresourceslit.gif', '',   '',   154,   0,   2,   154,  'menuresources' );
menu[0][4] = new Item(  'Products',    'images/menuproducts.gif',  'images/menuproductslit.gif',  '',   '',   153,   0,   4,   153,  'menuproducts'  );
menu[0][5] = new Item(  'Personal',    'images/menupersonal.gif',  'images/menupersonallit.gif',  '',   '',   153,   0,   5,   153,  'menupersonal'  );


// Guests Menu
menu[1] = new Array();
menu[1][0] = new Menu(true, 0, 20, 152, defBack );
menu[1][1] = new Item(  'Guest Book',      'images/menuguestsguestbook.gif',    'images/menuguestsguestbooklit.gif',    '', '', defLength, 0, 0, 152, 'menuguestsguestbook'        );
menu[1][2] = new Item(  'Bulletin Board',  'images/menuguestsbulletinboard.gif', 'images/menuguestsbulletinboardlit.gif', '', '', defLength, 0, 0, 152, 'menuguestsbulletinboard' );
menu[1][3] = new Item(  'Gateway',  'images/menuguestsgateway.gif', 'images/menuguestsgatewaylit.gif', 'gateway.htm', '', defLength, 0, 0, 152, 'menuguestsgateway' );


// Resources Menu
menu[2] = new Array();
menu[2][0] = new Menu(true, 0, 20, 152, defBack );
menu[2][1] = new Item(  'Programming',  'images/menuresourcesprogramming.gif',  'images/menuresourcesprogramminglit.gif',   '', '', defLength, 0, 3, 152, 'menuresourcesprogramming'   );
menu[2][2] = new Item(  'Music',        'images/menuresourcesmusic.gif',        'images/menuresourcesmusiclit.gif',         '', '', defLength, 0, 0, 152, 'menuresourcesmusic'         );
menu[2][3] = new Item(  'Electronics',  'images/menuresourceselectronics.gif',  'images/menuresourceselectronicslit.gif',   '', '', defLength, 0, 0, 152, 'menuresourceselectronics'   );

// Resources Programming Menu
menu[3] = new Array();
menu[3][0] = new Menu(true, 152, 0, 152, defBack );
menu[3][1] = new Item(  'Sample Code',        'images/menuresourcesprogrammingsamplecode.gif',        'images/menuresourcesprogrammingsamplecodelit.gif',       '', '', defLength, 0, 0, 152, 'menuresourcesprogrammingsamplecode'   );
menu[3][2] = new Item(  'Technical Articles', 'images/menuresourcesprogrammingtechnicalarticles.gif', 'images/menuresourcesprogrammingtechnicalarticleslit.gif','', '', defLength, 0, 0, 152, 'menuresourcesprogrammingtechnicalarticles'         );

// Products Menu
menu[4] = new Array();
menu[4][0] = new Menu(true, 0, 20, 152, defBack );
menu[4][1] = new Item(  'Programming Services', 'images/menuproductsprogrammingservices.gif',   'images/menuproductsprogrammingserviceslit.gif', '', '', defLength, 0, 0, 152, 'menuproductsprogrammingservices'   );

// Personal Menu
menu[5] = new Array();
menu[5][0] = new Menu(true, 0, 20, 152, defBack );
menu[5][1] = new Item(  'Resume',           'images/menupersonalresume.gif',        'images/menupersonalresumelit.gif',         '', '', defLength, 0, 6, 152, 'menupersonalresume'   );
menu[5][2] = new Item(  'Contact Info.',    'images/menupersonalcontactinfo.gif',   'images/menupersonalcontactinfolit.gif',    '', '', defLength, 0, 0, 152, 'menucontactinfo'   );
menu[5][3] = new Item(  'Private',          'images/menupersonalprivate.gif',       'images/menupersonalprivatelit.gif',        '', '', defLength, 0, 0, 152, 'menupersonalprivate'   );

// Personal Resume Menu
menu[6] = new Array();
menu[6][0] = new Menu(true, 152, 0, 152, defBack );
menu[6][1] = new Item(  'Work History',  'images/menupersonalresumeworkhistory.gif', 'images/menupersonalresumeworkhistorylit.gif', '', '', defLength, 0, 0, 152, 'menupersonalresumeworkhistory'   );
menu[6][2] = new Item(  'Skill Set',     'images/menupersonalresumeskillset.gif', 'images/menupersonalresumeskillsetlit.gif',       '', '', defLength, 0, 0, 152, 'menupersonalresumeskillset'   );



// *** OPTIONAL CODE FROM HERE DOWN ***

// These two lines handle the window resize bug in NS4. See <body onResize="...">.
// I recommend you leave this here as otherwise when you resize NS4's width menus are hidden.

var popOldWidth = window.innerWidth;
nsResizeHandler = new Function('if (popOldWidth != window.innerWidth) location.reload()');


// This is a quick snippet that captures all clicks on the document and hides the menus
// every time you click. Use if you want.

if (isNS4) document.captureEvents(Event.CLICK);
document.onclick = clickHandle;

function clickHandle(evt)
{
 if (isNS4) document.routeEvent(evt);
 hideAllBut(0);
}


// This is just the moving command for the example.

function moveRoot()
{
 with(menu[0][0].ref) left = ((parseInt(left) < 100) ? 100 : 5);
}