var $ = function (d){return document.getElementById( d );};
var isIE = (document.all) ? true : false;
var Bind = function (obj,fun,arr){return function() {arr || (arr = arguments);return fun.apply(obj,arr);}};//绑定
var Tween =  function(t,b,c,d){return c*t/d + b;};//缓冲函数
function addEventHandler(oTarget, sEventType, fnHandler) {if (oTarget.addEventListener) {oTarget.addEventListener(sEventType, fnHandler, false);} else if (oTarget.attachEvent) {oTarget.attachEvent("on" + sEventType, fnHandler);} else {oTarget["on" + sEventType] = fnHandler;
	}
};//事件监听
function removeEventHandler(oTarget, sEventType, fnHandler) {
    if (oTarget.removeEventListener) {
        oTarget.removeEventListener(sEventType, fnHandler, false);
    } else if (oTarget.detachEvent) {
        oTarget.detachEvent("on" + sEventType, fnHandler);
    } else { 
        oTarget["on" + sEventType] = null;
    }
};//移除监听

var Timer = {};//Timer
Timer.add = function (fn){return new this.fn(fn)};
Timer.fn = function (fn){
  var timer;
  this.play = function (speed,only){
    speed || ( speed = 10 );
	if(only)timer = window.setTimeout(fn,speed);
    else timer = window.setInterval(fn,speed);
  };
  this.stop = function (){clearTimeout(timer);clearInterval(timer)};
};
//Mask 遮罩动画
var Mask = function (){
	 this.fl = Timer.add(Bind(this,this.fn));
	 this.from_num = 0;
	 this.speed = 50;//动画速度，越大越慢
};
Mask.prototype.ready = function (ele,pos){
     if(this.ele)this.set(this.maxWidth,this.maxHeight);
     this.ele = ele;
     this.maxWidth = this.ele.offsetWidth;
	 this.maxHeight = this.ele.offsetHeight;
	 this.ele.style.position = "absolute";
	 this.from_num = 0;
	 if(!pos){
		 var  x = ["left","center","right",""][parseInt(4*Math.random())],
              y = ["top","center","bottom",""][parseInt(4*Math.random())];
		if(x == "" && y == "")x = "left";//避免同时为""	  
	     this.position = [x,y];		  
	 }else{
	    this.position = pos;
	 }
	 this.set(0,0);
	 this.fl.stop();
};
Mask.prototype.start = function (){this.fl.play();};
Mask.prototype.stop = function (){this.fl.stop();};
Mask.prototype.set = function (width,height){//设置遮罩的矩形，用于定位遮罩的变换方向
    var t,r,b,l;
	switch(this.position[0]){
	 case "left"   : 
	      l = 0; 
		  r = width; 
		  break;
	 case "center" : 
	      l = (this.maxWidth - width)/2; 
		  r = (this.maxWidth + width)/2;
		  break;
	 case "right"  : 
	      l = this.maxWidth - width;
		  r = this.maxWidth; 
		  break;
	 default:
	      l = 0;
		  r = this.maxWidth; 	  
	}
    switch(this.position[1]){
	 case "top"    : 
	      t = 0; 
		  b = height; 
		  break;
	 case "center" : 
	      t = (this.maxHeight - height)/2; 
		  b = (this.maxHeight + height)/2;
		  break;
	 case "bottom"  : 
	      t = this.maxHeight - height;
		  b = this.maxHeight; 
		  break;
	 default :
	      t = 0;
		  b = this.maxHeight;
		  break;	  
	}
	this.ele.style.clip = "rect("
	+ t + "px,"
	+ r + "px,"
	+ b + "px,"
	+ l + "px)" ;
};
Mask.prototype.fn = function (){
     var w,h; 
     this.from_num ++ ;
	 if(this.from_num<=this.speed){
	    w = Tween(this.from_num,0,this.maxWidth,this.speed);
		h = Tween(this.from_num,0,this.maxHeight,this.speed);
		this.set(w,h);
	 }else{
	    this.fl.stop();
		//this.start();//若不需要重复动画，把这句注释，上句不注释
	 }
	 
};
function ImgFlash(box){
        this.box = box.getElementsByTagName("dl");
		this.ge = 4;//切换间隔秒数
		this.menu = [];
		this.mask = new Mask();//加载遮罩动画，不设置参数 即 随机效果
		this.zIndex = this.box.length;
		var _div = document.createElement('div');
		this.dang = 0;
		for(i=0;i<this.zIndex;i++){
			this.box[i].style.zIndex = this.zIndex-i;
			var _em = document.createElement('em'),_span = document.createElement('span');
			var _dt = this.box[i].getElementsByTagName("dt")[0];
			_dt.appendChild(_span);
			addEventHandler(_em,'mouseover',Bind(this,this.emEvent,[this.zIndex-i-1,true]));
			_div.appendChild(_em);
			this.menu.push(_em);
			if(this.zIndex-i==1){
			_em.className = 'd';
			}
		}
		box.appendChild(_div);
		addEventHandler(box,'mouseover',Bind(this,function(){this.fl.stop()}));
		addEventHandler(box,'mouseout',Bind(this,function(){this.fl.play(this.ge*1000)}));
		this.fl = Timer.add(Bind(this,this.enterFrame))
		this.fl.play(this.ge*1000);
}
ImgFlash.prototype.enterFrame = function(){
        var ddd = this.dang==2?0:this.dang+1;
		this.emEvent(ddd);	
};
ImgFlash.prototype.emEvent = function (index,b){
		if(b)this.fl.stop();
		if(index == this.dang)return;
		this.menu[this.menu.length-1-this.dang].className="";
		var odl = this.box[this.dang];
		this.zIndex++;
		this.dang = index;
		this.menu[this.menu.length-1-this.dang].className="d";
		var ndl = this.box[this.dang];
		var img = ndl.getElementsByTagName("img")[0];
		this.mask.ready(img);
		this.mask.start();
		ndl.style.zIndex = this.zIndex;
}
function Tab(id,type){
  var nav = id.getElementsByTagName("ul")[0].childNodes;
  var _nav,i=0;
  this.mask = new Mask();//初始化遮罩动画
  this.z = 1000;
  while(_nav = nav[i++]){
   if(_nav.className=="d")this.focusEle = _nav;
   if(_nav.childNodes.length>1){
    var A = _nav.getElementsByTagName("A")[0];
    addEventHandler(A,type,Bind(this,fun,[A]));
   }
   if(_nav.nodeType == 1)_nav.getElementsByTagName("UL")[0].style.zIndex = nav.length-i;
  }
  function fun(ele){
   var li = ele.parentNode;
   var ul = li.getElementsByTagName("UL")[0];
   this.z += 1
   ul.style.zIndex = this.z;
   if(li.className=="d")return;
   li.className+=(li.className.length>0? " ": "") + "d";
   this.focusEle.className=this.focusEle.className.replace(/( ?|^)d\b/g, "");
   this.focusEle = li;
   this.mask.ready(ul);
   this.mask.start();
  };
}