var g_oMainActive = null;
var g_bMayHideSubMenu = false;
var g_sMainMenu_NormalClassName = null;

var g_oSubDisplayed = new Array();

function InitializeClassNames(sMainMenu_NormalClassName)
{
    g_sMainMenu_NormalClassName = sMainMenu_NormalClassName;
}

function ShowSubMenu(sMainMenuId, sSubMenuId, nLevel, sTopOffset, sLeftOffset)
{
    var oMainMenu = document.getElementById(sMainMenuId);
	var oSubMenu = document.getElementById(sSubMenuId);
	
	if (g_oMainActive != null)
	{
	    HideSubMenu(nLevel);
	}
	
	oSubMenu.style.top = sTopOffset;
	oSubMenu.style.left = sLeftOffset;
	oSubMenu.style.zindex = nLevel;
	
	oSubMenu.style.display = 'block';
	
	g_oMainActive = oMainMenu;
	g_oSubDisplayed.push(oSubMenu);
	
	g_bMayHideSubMenu = false; 
	setTimeout('g_bMayHideSubMenu = true', 50);     // displayed menu can be hidden after 50 ms;
}

function HideSubMenu(nLevel)
{
    if (g_bMayHideSubMenu)
    {
        if (g_oSubDisplayed.length > nLevel)
        {
            for (i = nLevel; i < g_oSubDisplayed.length; i++)
            {
                g_oSubDisplayed[i].style.display = "none";
            }
            g_oSubDisplayed.splice(nLevel, g_oSubDisplayed.length);
            if(g_oMainActive != null)
            {
                g_oMainActive.className = g_sMainMenu_NormalClassName;
                g_oMainActive = null;
            }
	    }
	    g_bMayHideSubMenu = false;
	}
}

function DelayFullMenuHiding()
{
    g_bMayHideSubMenu = false; 
    setTimeout('g_bMayHideSubMenu = true', 50);
}

function ChangeMainMenu(oItem, sNewClassName)
{
    oItem.className = sNewClassName;
}

function ChangeClass(oItem, sNewClassName)
{
    oItem.className = sNewClassName;
}