var TimeOut         = 300;
var currentLayer    = null;
var currentLayerNum = 0;
var closeTimer      = null;
var subcurrentLayer    = null;
var subcurrentLayerNum = 0;
var subcloseTimer      = null;

function image_change(name,mno,no) {
        image = "../image/menu_button_" + mno + no + ".jpg";
        document.images[name].src = image;
        if ( mno == 1 || mno == 2 ) {
                if ( no == 1 ) mclosetime();
                if ( no == 2 ) menu_open(mno);
        }
}

function menu_open(mno) {
    var subm  = document.getElementById("submenu" + mno);
        mcancelclosetime();
        subm.style.visibility = 'visible';
        if ( currentLayer && ( currentLayerNum != mno )) {
                currentLayer.style.visibility = "hidden";
        }
        currentLayer = subm;
        currentLayerNum = mno;
}

function submenu_open(mno) {
    var subm  = document.getElementById("submenu" + mno);
        submcancelclosetime();
        subm.style.visibility = 'visible';
        if ( subcurrentLayer && ( subcurrentLayerNum != mno )) {
                subcurrentLayer.style.visibility = "hidden";
        }
        subcurrentLayer = subm;
        subcurrentLayerNum = mno;
}

function mclosetime() {
        if ( subcurrentLayer == null ) {
                closeTimer = window.setTimeout(mclose, TimeOut);
        }
}

function submclosetimeA() {
        subcloseTimer = window.setTimeout(submcloseA, TimeOut);
}

function submclosetimeB() {
        subcloseTimer = window.setTimeout(submcloseB, TimeOut);
}

function mcancelclosetime() {
        if(closeTimer) {
                window.clearTimeout(closeTimer);
                closeTimer = null;
        }
}

function submcancelclosetime() {
        if(subcloseTimer) {
                window.clearTimeout(subcloseTimer);
                subcloseTimer = null;
        }
}

function mclose() {
        if(currentLayer)   {
                currentLayer.style.visibility='hidden';
                currentLayerNum = 0;
                currentLayer = null;
        }
        currentLayer = null;
}

function submcloseA() {
        if(subcurrentLayer)   {
                subcurrentLayer.style.visibility='hidden';
                subcurrentLayerNum = 0;
                subcurrentLayer = null;
        }
        subcurrentLayer = null;
}

function submcloseB() {
        if(subcurrentLayer)   {
                subcurrentLayer.style.visibility='hidden';
                subcurrentLayerNum = 0;
                subcurrentLayer = null;
                currentLayer.style.visibility='hidden';
                currentLayerNum = 0;
                currentLayer = null;
        }
        subcurrentLayer = null;
}