var Hongru={};
function H$(id){return document.getElementById(id)}
function H$$(c,p){return p.getElementsByTagName(c)}
Hongru.fader = function(){
    function init(anchor,options){
        this.anchor = anchor;
        var wp = H$(options.id),
            ul = H$$('ul',wp)[0],
            li = this.li = H$$('li',ul);
        this.index = options.position?options.position:0;
        this.a = options.auto?options.auto:2;
        this.cur = this.z = 0;
        this.l = li.length;
        this.img = [];
        for(var k=0;k<this.l;k++){
            this.img.push(H$$('img',this.li[k])[0]);
        }
        this.curC = options.curNavClass?options.curNavClass:'fader-cur-nav';
        nav_wp = document.createElement('div');
        nav_wp.id = 'fader-nav';
        nav_wp.style.cssText = 'position:absolute;right:0;bottom:0;padding:0 0;';
        var alt = this.alt = document.createElement('p');
        for(var i=0;i<this.l;i++){
            this.li[i].o = 100;
            //setOpacity(this.li[i],this.li.o);
            this.li[i].style.opacity = this.li[i].o/100;
            this.li[i].style.filter = 'alpha(opacity='+this.li[i].o+')';
            //绘制控制器
            var nav = document.createElement('a');
            nav.className = options.navClass?options.navClass:'fader-nav';
            nav.innerHTML = i+1;
            nav.onclick = new Function(this.anchor+'.pos('+i+')');
            nav_wp.appendChild(nav);
        }
        wp.appendChild(alt);        
        wp.appendChild(nav_wp);
        this.textH = nav_wp.offsetHeight;
                alt.style.cssText = '';
                alt.style.height = alt.style.lineHeight = this.textH+'px';
        this.pos(this.index);
    }
    init.prototype={
        auto:function(){
            this.li.a = setInterval(new Function(this.anchor+'.move(1)'),this.a*1000); 
        },
        move:function(i){
            var n = this.cur+i;
            var m = i==1?n==this.l?0:n:n<0?this.l-1:n;
            this.pos(m);
        },
        pos:function(i){
            clearInterval(this.li.a);
            clearInterval(this.li[i].f);
            var curLi = this.li[i];
            this.z++;
            curLi.style.zIndex = this.z;
            this.alt.style.zIndex = this.z+1;
            nav_wp.style.zIndex = this.z+2;
            this.li.a=false; //这句话是必要的
            this.cur = i;
            //setOpacity(curLi[i],0);
            if(this.li[i].o>=100){
                this.li[i].o = 0;
                curLi.style.opacity = 0;
                curLi.style.filter = 'alpha(opacity=0)';
                this.alt.style.height = '0px';
            }
            for(var x=0;x<this.l;x++){
                nav_wp.getElementsByTagName('a')[x].className = x==i?this.curC:'fader-nav';
                }
            this.alt.innerHTML = this.img[i].alt;
            this.li[i].f = setInterval(new Function(this.anchor+'.fade('+i+')'),20);
        },
        fade:function(i){
        var p=this.li[i];
            if(p.o>=100){
                clearInterval(p.f);
                if(!this.li.a){ //一定要在这里做个是否已经clearInterval的判断，要不然在快速点击的时候会导致图片不停地闪
                    this.auto();
                }
            }
            else{
                p.o+=5;
                //setOpacity(this.li[i],this.li[i].o);
                p.style.opacity = p.o/100;
                p.style.filter = 'alpha(opacity='+p.o+')';
                this.alt.style.height = Math.ceil(p.o*this.textH/100)+'px';
            }
        }
    };
    return {init:init};
}();