function checkIEVersion() {
    var version = 999;
    if (navigator.appVersion.indexOf("MSIE") != -1) {
        version = parseFloat(navigator.appVersion.split("MSIE")[1]);
    }
      
    return version;
}

var MainMenuTime = 0;

var MainMenuData = 
{
    'current_td' : ""
}

function changeMenutd(td_obj,add_css,remove_css) {
    $(td_obj).removeClassName(remove_css);
    $(td_obj).addClassName(add_css);
}

function gotoMenuPage(goto_page) {  
    window.open(goto_page,"_self");
}

function openSubMenu(td_name,add_css,remove_css) {
    clearTimeout(MainMenuTime);
    var div_name = "menu_div_" + td_name;
    
    if (MainMenuData.current_td != td_name) {
        if (MainMenuData.current_td != "") {
            closeMenu(MainMenuData.current_td,remove_css,add_css);
        }
        changeMenutd("menu_td_" + td_name,add_css,remove_css);
    
        if ($(div_name) != null) {    
            var menu_td = $("menu_td_" + td_name);
            var hidden_div = $(div_name);
        
            // caculate the position start
            try{
            var td_position = menu_td.positionedOffset();
            var top = td_position.top + 24;
            var left = td_position.left + 1;              
            
            hidden_div.setStyle({left:left+"px",top:top+"px"});
            } catch(e) {
                alert(e.message);
            }
            // caculate the position end 
        
            MainMenuData.current_td = td_name;
            hidden_div.style.display = "block";
        }
    
    }
}

function closeSubMenu(td_name,add_css,remove_css) {
    var div_name = "menu_div_" + td_name;

    if ($(div_name) != null) {
        MainMenuTime = setTimeout(function() {closeMenu(td_name,add_css,remove_css);},'500');
    } else {
        changeMenutd("menu_td_" + td_name,add_css,remove_css);
    }
}

function closeMenu(td_name,add_css,remove_css) {
    var div_name = "menu_div_" + td_name;

    changeMenutd("menu_td_" + td_name,add_css,remove_css);
    MainMenuData.current_td = "";
    $(div_name).style.display = "none";
}