var jqueryslidemenu={

    animateduration: {over: 200, out: 300},

    buildmenu:function(menuid){
        jQuery(document).ready(function($){
            var $mainmenu=$("#"+menuid+">ul")
            var $headers=$mainmenu.find("ul").parent()
            $headers.each(function(i){
                var $curobj=$(this)
                var $subul=$(this).find('ul:eq(0)')
                this._dimensions={w:this.offsetWidth, h:this.offsetHeight, subulw:$subul.outerWidth(), subulh:$subul.outerHeight()}
                this.istopheader=$curobj.parents("ul").length==1? true : false
                $subul.css({top:this.istopheader? this._dimensions.h+"px" : 0})
                $curobj.hover(
                    function(e){
                        var $targetul=$(this).children("ul:eq(0)")
                        this._offsets={left:$(this).offset().left, top:$(this).offset().top}
                        var menuleft=this.istopheader? 0 : this._dimensions.w
                        menuleft=(this._offsets.left+menuleft+this._dimensions.subulw>$(window).width())? (this.istopheader? -this._dimensions.subulw+this._dimensions.w : -this._dimensions.w) : menuleft
                        if ($targetul.queue().length<=1)
                            $targetul.css({left:menuleft+"px", width:this._dimensions.subulw+'px'}).slideDown(jqueryslidemenu.animateduration.over)
                    },
                    function(e){
                        var $targetul=$(this).children("ul:eq(0)")
                        $targetul.slideUp(jqueryslidemenu.animateduration.out)
                    }
                )
            })
            $mainmenu.find("ul").css({display:'none', visibility:'visible'})
        })
    }
}

// build menu
jqueryslidemenu.buildmenu("menuprincipal")