calendar and calendar overlay

var cal = null;
var calOverlay = new YAHOO.widget.Overlay('cal-overlay', {
    xy: [-5000, -5000],
    visible: false,
    width: '200px'
});

// align thte cal-overlay
calOverlay.beforeShowEvent.subscribe(function () {
    calOverlay.cfg.setProperty('context', [
        Dom.get('cal-context'), 'tl', 'bl'
    ]);
});

calOverlay.setBody('
');

// render the calendar
calOverlay.renderEvent.subscribe(function () {
    cal = new YAHOO.widget.Calendar("cal-container");
    cal.selectEvent.subscribe(function (type, args, obj) {
        Dom.get('cal-context').value = args[0][0].join('/');
        calOverlay.hide();
    }, cal, true);
    cal.render();
});

calOverlay.render(document.body);

Event.on('cal-toggle', 'click', function () {
    if (!Dom.get('cal-context').disabled) {
        calOverlay.show();
    }
});

// hide the cal-overlay if blur
var onCalOverlayBlur = function (e) {
    var target = Event.getTarget(e);

    if (!Dom.isAncestor('cal-overlay', target) && target.id != 'cal-toggle') {
        calOverlay.hide();
    }
};

Event.on(document.body, 'click', onCalOverlayBlur);