ldh={
    $:function(o){return typeof o=="string"?document.getElementById(o):o},
    $$:function (o,p){return (p==undefined?document:this.$(p)).getElementsByTagName(o)},
    on:function(o,type,fn){o.attachEvent?o.attachEvent('on'+type,function(){fn.call(o)}):o.addEventListener(type,fn,false);},
    opacity:function(who,x){
        who=this.$(who);
        if(x==undefined){
            if( !!window.ActiveXObject){
                return who.filters.alpha?(who.filters.alpha.opacity/100):1;
            }else{
                var op=who.style.opacity;
                return isNaN(op)?1:op*1;
            }
        }
        who.style.filter="alpha(opacity="+parseInt(x*100)+")";
        who.style.opacity=x;
        return this;
    },
    fadeTo:function(who,x,fn){
        who=this.$(who);
        var fm=this.opacity(who),m=1,r=Math.floor,s=2,v;
        if(fm>x){m=-1;r=Math.ceil;s=1};
        var iFx=function(){return fm=r((fm+m*0.02*s)*100)/100};
        clearInterval(who.opacityTimer);
        who.opacityTimer=setInterval(function (){
            var v=Math.max(0,Math.min(x,iFx()));
            ldh.opacity(who,v);
            if(v==x){
                fn&&fn.call(who);
                clearInterval(who.opacityTimer);
            };
        },13);return this;
    },
    fadeOut:function(who,fn){return this.fadeTo(who,0,fn)},
    fadeIn:function(who,fn){return this.fadeTo(who,1,fn)},
    move:function(who,attr,val,s,fn){
        who=this.$(who);
        var fm=parseInt(who.style[attr])||0;
        var iFx=this.fx(fm,val,s);
        clearInterval(who.moveTimer);
        who.moveTimer=setInterval(function (){
            var v=iFx();
            who.style[attr]=v+'px';
            if(v==val){
                fn&&fn.call(who);
                clearInterval(who.moveTimer);
            };
        },13);return this;
    },
    fx:function(form,to,s){
        var m=Math[form<to?'ceil':'floor'];
        return function (){return form+=m((to-form)*(s||0.13))};
    }
};
try{document.execCommand("BackgroundImageCache", false, true);}catch(e){};//for IE6
shower={
    init:function(setting){
        var ini={box:ldh.$(setting.box),tip:ldh.$(setting.tip),index:0,z:99,list:[]};
        for(var Id in ini)this[Id]=ini[Id];
        var imgs=ldh.$$('img',this.box);
        for (var i=0;i<imgs.length;++i ) {
            this.list.push(imgs[i]);
            imgs[i].style.zIndex=i;
        };
        this.tip.innerHTML=imgs[0].getAttribute('alt');
        this.hideTip();
    },
    show:function(){
        var p2=this.list[this.index++];
        if(this.index==this.list.length)this.index=0;
        ldh.opacity(p2,0);
        p2.style.zIndex=++this.z;
        ldh.fadeIn(p2,function (){
            shower.tip.innerHTML=p2.getAttribute('alt');
            ldh.move(shower.tip,'bottom',0,0.1,function (){
                    setTimeout(function(){shower.hideTip()},4000);
            }).opacity(shower.tip,0.8);                    
        })
    },
    hideTip:function(){
        shower.show();
        ldh.move(this.tip,'bottom',-100,0.05);
    }
}

ldh.on(window,'load',function (){
    shower.init({
        box:'fx_box',
        tip:'tip'
    });
})