var YUD = YAHOO.util.Dom;
var YUE = YAHOO.util.Event;
YAHOO.util.Event.onContentReady("menuHorizontal", function(){

    var Dom = YAHOO.util.Dom, oAnim; // Animation instance
    /*
     "beforeshow" event handler for each submenu of the MenuBar
     instance, used to setup certain style properties before
     the menu is animated.
     */
    function onSubmenuBeforeShow(p_sType, p_sArgs){
    
        var oBody, oShadow, oUL;
        
        if (this.parent) {
        
            /*
             Get a reference to the Menu's shadow element and
             set its "height" property to "0px" to syncronize
             it with the height of the Menu instance.
             */
            oShadow = this.element.lastChild;
            oShadow.style.height = "0px";
                        
            /*
             Stop the Animation instance if it is currently  animating a Menu.
             */
            if (oAnim && oAnim.isAnimated()) {
            
                oAnim.stop();
                oAnim = null;
                
            }
            
            
            /*
             Set the body element's "overflow" property to
             "hidden" to clip the display of its negatively
             positioned <ul> element.
             */
            oBody = this.body;
                       
            /*
             There is a bug in gecko-based browsers where
             an element whose "position" property is set to
             "absolute" and "overflow" property is set to
             "hidden" will not render at the correct width when
             its offsetParent's "position" property is also
             set to "absolute."  It is possible to work around
             this bug by specifying a value for the width
             property in addition to overflow.
             */
            if (this.parent &&
            !(this.parent instanceof YAHOO.widget.MenuBarItem) &&
            YAHOO.env.ua.gecko) {
                Dom.setStyle(oBody, "width", (oBody.clientWidth + "px"));
            }
            Dom.setStyle(oBody, "overflow", "hidden");           
            /*
             Set the <ul> element's "marginTop" property
             to a negative value so that the Menu's height
             collapses.
             */
            oUL = oBody.getElementsByTagName("ul")[0];
            
            Dom.setStyle(oUL, "marginTop", ("-" + oUL.offsetHeight + "px"));   
        }
    }
    
    /*
     "tween" event handler for the Anim instance, used to
     syncronize the size and position of the Menu instance's
     shadow and iframe shim (if it exists) with its
     changing height.
     */
    function onTween(p_sType, p_aArgs, p_oShadow){
        if (this.cfg.getProperty("iframe")) {
            this.syncIframe();
        }
        if (p_oShadow) {
            p_oShadow.style.height = this.element.offsetHeight + "px";
        }
    }
    /*
     "complete" event handler for the Anim instance, used to
     remove style properties that were animated so that the
     Menu instance can be displayed at its final height.
     */
    function onAnimationComplete(p_sType, p_aArgs, p_oShadow){
    
        var oBody = this.body, oUL = oBody.getElementsByTagName("ul")[0];
        
        if (p_oShadow) {
        
            p_oShadow.style.height = this.element.offsetHeight + "px";
            
        }
        
        Dom.setStyle(oUL, "marginTop", "");
        Dom.setStyle(oBody, "overflow", "");
        
        
        if (this.parent &&
        !(this.parent instanceof YAHOO.widget.MenuBarItem) &&
        YAHOO.env.ua.gecko) {
        
            Dom.setStyle(oBody, "width", "");
            
        }
        
    }
    
    
    /*
     "show" event handler for each submenu of the MenuBar
     instance - used to kick off the animation of the
     <ul> element.
     */
    function onSubmenuShow(p_sType, p_sArgs){
    
        var oElement, oShadow, oUL;
        
        if (this.parent) {
        
            oElement = this.element;
            oShadow = oElement.lastChild;
            oUL = this.body.getElementsByTagName("ul")[0];
            
            
            /*
             Animate the <ul> element's "marginTop" style
             property to a value of 0.
             */
            oAnim = new YAHOO.util.Anim(oUL, {
                marginTop: {
                    to: 0
                }
            }, .15, YAHOO.util.Easing.easeOut);
            
            
            oAnim.onStart.subscribe(function(){
            
                oShadow.style.height = "100%";
                
            });
            
            
            oAnim.animate();
            
            
            /*
             Subscribe to the Anim instance's "tween" event for
             IE to syncronize the size and position of a
             submenu's shadow and iframe shim (if it exists)
             with its changing height.
             */
            if (YAHOO.env.ua.ie) {
            
                oShadow.style.height = oElement.offsetHeight + "px";
                
                
                /*
                 Subscribe to the Anim instance's "tween"
                 event, passing a reference Menu's shadow
                 element and making the scope of the event
                 listener the Menu instance.
                 */
                oAnim.onTween.subscribe(onTween, oShadow, this);
                
            }
            
            
            /*
             Subscribe to the Anim instance's "complete" event,
             passing a reference Menu's shadow element and making
             the scope of the event listener the Menu instance.
             */
            oAnim.onComplete.subscribe(onAnimationComplete, oShadow, this);
            
        }
        
    }
    
    
    /*
     Instantiate a MenuBar:  The first argument passed to the
     constructor is the id of the element in the page
     representing the MenuBar; the second is an object literal
     of configuration properties.
     */
    var oMenuBar = new YAHOO.widget.MenuBar("menuHorizontal", {
        autosubmenudisplay: true,
        hidedelay: 750,
        lazyload: true
    });
    
    
    /*
     Subscribe to the "beforeShow" and "show" events for
     each submenu of the MenuBar instance.
     */
    oMenuBar.subscribe("beforeShow", onSubmenuBeforeShow);
    oMenuBar.subscribe("show", onSubmenuShow);
    
    
    /*
     Call the "render" method with no arguments since the
     markup for this MenuBar already exists in the page.
     */
    oMenuBar.render();
    
});