/* Script by: www.jtricks.com 
 * Version: 20071017 
 * Latest version: 
 * www.jtricks.com/javascript/navigation/floating.html 
 */  
var floatingMenuId = 'menu_float';  
var floatingMenu =  
{  
  
    hasInner: typeof(window.innerWidth) == 'number',  
    hasElement: typeof(document.documentElement) == 'object'  
        && typeof(document.documentElement.clientWidth) == 'number',  
  
    targetX: 0,  
    targetY: 115,  
    menu:  
        document.getElementById  
        ? document.getElementById(floatingMenuId)  
        : document.all  
          ? document.all[floatingMenuId]  
          : document.layers[floatingMenuId]  
};  
  
floatingMenu.move = function ()  
{  
    floatingMenu.menu.style.left = floatingMenu.nextX + 'px';  
    floatingMenu.menu.style.top = floatingMenu.nextY + 'px';  
}  
  
floatingMenu.computeShifts = function ()  
{  
    var de = document.documentElement;  
  
    floatingMenu.shiftX =    
        floatingMenu.hasInner    
        ? pageXOffset    
        : floatingMenu.hasElement    
          ? de.scrollLeft    
          : document.body.scrollLeft;    
    if (floatingMenu.targetX < 0)  
    {  
        floatingMenu.shiftX +=  
            floatingMenu.hasElement  
            ? de.clientWidth  
            : document.body.clientWidth;  
    }  
  
    floatingMenu.shiftY =   
        floatingMenu.hasInner  
        ? pageYOffset  
        : floatingMenu.hasElement  
          ? de.scrollTop  
          : document.body.scrollTop;  
    if (floatingMenu.targetY < 0)  
    {  
        if (floatingMenu.hasElement && floatingMenu.hasInner)  
        {  
            // Handle Opera 8 problems  
            floatingMenu.shiftY +=  
                de.clientHeight > window.innerHeight  
                ? window.innerHeight  
                : de.clientHeight  
        }  
        else  
        {  
            floatingMenu.shiftY +=  
                floatingMenu.hasElement  
                ? de.clientHeight  
                : document.body.clientHeight;  
        }  
    }  
}  
  
floatingMenu.calculateCornerX = function()  
{  
    if (floatingMenu.targetX != 'center')  
        return floatingMenu.shiftX + floatingMenu.targetX;  
  
    var width = parseInt(floatingMenu.menu.offsetWidth);  
  
    var cornerX =  
        floatingMenu.hasElement  
        ? (floatingMenu.hasInner  
           ? pageXOffset  
           : document.documentElement.scrollLeft) +   
          (document.documentElement.clientWidth - width)/2  
        : document.body.scrollLeft +   
          (document.body.clientWidth - width)/2;  
    return cornerX;  
};  
  
floatingMenu.calculateCornerY = function()  
{  
    if (floatingMenu.targetY != 'center' && floatingMenu.shiftY == 0)  
        return floatingMenu.shiftY + floatingMenu.targetY;  
  
    if (floatingMenu.targetY != 'center')  
        return floatingMenu.shiftY ;  
  
    var height = parseInt(floatingMenu.menu.offsetHeight);  
  
    // Handle Opera 8 problems  
    var clientHeight =   
        floatingMenu.hasElement && floatingMenu.hasInner  
        && document.documentElement.clientHeight   
            > window.innerHeight  
        ? window.innerHeight  
        : document.documentElement.clientHeight  
  
    var cornerY =  
        floatingMenu.hasElement  
        ? (floatingMenu.hasInner    
           ? pageYOffset 
           : document.documentElement.scrollTop) +   
          (clientHeight - height)/2  
        : document.body.scrollTop +   
          (document.body.clientHeight - height)/2;  
    return cornerY;  
};  
  
floatingMenu.doFloat = function()  
{  
    var stepX, stepY;  
  
    floatingMenu.computeShifts();  
  
    var cornerX = floatingMenu.calculateCornerX();  
  
    var stepX = (cornerX - floatingMenu.nextX) * .07;  
    if (Math.abs(stepX) < .5)  
    {  
        stepX = cornerX - floatingMenu.nextX;  
    }  
  
    var cornerY = floatingMenu.calculateCornerY();  
  
    var stepY = (cornerY - floatingMenu.nextY) * .07;  
    if (Math.abs(stepY) < .5)  
    {  
        stepY = cornerY - floatingMenu.nextY;  
    }  
  
    if (Math.abs(stepX) > 0 ||  
        Math.abs(stepY) > 0)  
    {  
        floatingMenu.nextX += stepX;  
        floatingMenu.nextY += stepY;  
        floatingMenu.move();  
    }  
  
    setTimeout('floatingMenu.doFloat()', 20);  
};  
  
// addEvent designed by Aaron Moore  
floatingMenu.addEvent = function(element, listener, handler)  
{  
    if(typeof element[listener] != 'function' ||   
       typeof element[listener + '_num'] == 'undefined')  
    {  
        element[listener + '_num'] = 0;  
        if (typeof element[listener] == 'function')  
        {  
            element[listener + 0] = element[listener];  
            element[listener + '_num']++;  
        }  
        element[listener] = function(e)  
        {  
            var r = true;  
            e = (e) ? e : window.event;  
            for(var i = element[listener + '_num'] -1; i >= 0; i--)  
            {  
                if(element[listener + i](e) == false)  
                    r = false;  
            }  
            return r;  
        }  
    }  
  
    //if handler is not already stored, assign it  
    for(var i = 0; i < element[listener + '_num']; i++)  
        if(element[listener + i] == handler)  
            return;  
    element[listener + element[listener + '_num']] = handler;  
    element[listener + '_num']++;  
};  
  
floatingMenu.init = function()  
{  
    floatingMenu.initSecondary();  
    floatingMenu.doFloat();  
};  
  
// Some browsers init scrollbars only after  
// full document load.  
floatingMenu.initSecondary = function()  
{  
    floatingMenu.computeShifts();  
    floatingMenu.nextX = floatingMenu.calculateCornerX();  
    floatingMenu.nextY = floatingMenu.calculateCornerY();  
    floatingMenu.move();  
}  
  
if (document.layers)  
    floatingMenu.addEvent(window, 'onload', floatingMenu.init);  
else  
{  
    floatingMenu.init();  
    floatingMenu.addEvent(window, 'onload',  
        floatingMenu.initSecondary);  
}