/**
    * ppt 盒子
    * 李清清 2012-05-17
    */
    function pptbox()
    {
        this.uid = pptboxhelper.getid();
        pptboxhelper.instance[this.uid] = this;
        this._$ = function(id){return document.getelementbyid(id);};
        this.width = 400;//宽度
        this.height = 300;//高度
        this.picwidth = 15;//小图宽度
        this.picheight = 12;//小图高度
        this.autoplayer = 4;//自动播放间隔（秒）
        this.target = "_blank";
        this._box = [];
        this._curindex = 0;
    }
    pptbox.prototype =
    {
        _createmainbox : function (){
            var flashboxwidth = this.width * this._box.length + 5;
            var html="<div id='"+this.uid+"_mainbox' class='mainbox'  style='width:"+(this.width)+"px;height:"+(this.height+2)+"px;'>";
            html += "<div id='"+this.uid+"_flashbox' class='flashbox' style='width:"+flashboxwidth+"px;height:"+(this.height+2)+"px;'></div>";
            html += "<div id='"+this.uid+"_imagebox' class='imagebox' style='width:"+this.width+"px;height:"+(this.picheight+2)+"px;top:-"+(this.picheight+20)+"px;'></div>";
            html += "</div>";
            document.write(html);
        },
        _init : function (){
            var picstyle= "";
            var eventstr = "pptboxhelper.instance['"+this.uid+"']";
            var imagehtml="";
            var flashbox = "";
            for(var i=0;i<this._box.length;i++){
                var parame = this._box[i];
                flashbox += this.flashhtml(parame.url,this.width,this.height,i);
                imagehtml ="<div class='bitdiv "+((i==0)?"curimg":"defimg")+"' title ="+parame.title+" src='bit01.gif' "+picstyle+" onclick = \""+eventstr+".clickpic("+i+")\"  onmouseover=\""+eventstr+".mouseoverpic("+i+")\"></div>" + imagehtml;
            }
            this._$(this.uid+"_flashbox").innerhtml = flashbox;
            this._$(this.uid+"_imagebox").innerhtml = imagehtml;

        },
        _play : function(){
            clearinterval(this._autoplay);
            var idx = this._curindex+1;
            if(idx>=this._box.length){idx=0;}
            this.changeindex(idx);
            var eventstr = "pptboxhelper.instance['"+this.uid+"']._play()";
            this._autoplay = setinterval(eventstr,this.autoplayer*1000);

        },
        flashhtml : function(url,width,height,idx) {
            var isflash = url.substring(url.lastindexof('.')+1).tolowercase()=="swf";
            var html = "";
            if(isflash){
                html = "<object classid='clsid:d27cdb6e-ae6d-11cf-96b8-444553540000' "
                + "codebase='http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=7,0,19,0' width='"+width+"' height='"+height+"'>"
                + "<param name=\"movie\" value=\""+url+"\" />"
                + "<param name='quality' value='high' />"
                + "<param name='wmode' value='transparent'>"
                + "<embed src='"+url+"' quality='high' wmode='opaque' pluginspage='http://www.macromedia.com/go/getflashplayer'"
                +"  type='application/x-shockwave-flash' width="+width+" height='"+height+"'></embed>"
                +"  </object>";
            } else {
                var eventstr = "pptboxhelper.instance['"+this.uid+"']";
                var style = "";
                if(this._box[idx].href){
                    style = "cursor:pointer"
                }
                html="<img src='"+url+"' style='width:"+width+"px;height:"+height+"px;"+style+"' onclick = \""+eventstr+".clickpic("+idx+")\"/>";
            }
            return html;
        },
        changeindex : function(idx){
            var parame = this._box[idx];
            moveelement(this.uid+"_flashbox",-(idx*this.width),1);
            var imgs = this._$(this.uid+"_imagebox").getelementsbytagname("div");
            imgs[this._box.length-1-this._curindex].classname = "bitdiv defimg";
            imgs[this._box.length-1-idx].classname = "bitdiv curimg";
            this._curindex = idx;
        },
        mouseoverpic:function(idx){
            this.changeindex(idx);
            if(this.autoplayer>0){
               clearinterval(this._autoplay);
               var eventstr = "pptboxhelper.instance['"+this.uid+"']._play()";
               this._autoplay = setinterval(eventstr,this.autoplayer*1000);
            }
        },
        clickpic:function(idx){
            var parame = this._box[idx];
            if(parame.href&&parame.href!=""){
                window.open(parame.href,this.target);
            }
        },
        add:function (imgparam){
            this._box[this._box.length] = imgparam;
        },
        show : function () {
           this._createmainbox();
           this._init();
           if(this.autoplayer>0){
               var eventstr = "pptboxhelper.instance['"+this.uid+"']._play()";
               this._autoplay = setinterval(eventstr,this.autoplayer*1000);
           }
        }
    }
    var pptboxhelper =
    {
        count: 0,
        instance: {},
        getid: function() { return '_ppt_box-' + (this.count++); }
    };

    function moveelement(elementid,final_x,interval) {
      if (!document.getelementbyid) return false;
      if (!document.getelementbyid(elementid)) return false;
      var elem = document.getelementbyid(elementid);
      if (elem.movement) {
        cleartimeout(elem.movement);
      }
      if (!elem.style.left) {
        elem.style.left = "0px";
      }
      var xpos = parseint(elem.style.left);
      if (xpos == final_x ) {
            return true;
      }
      if (xpos < final_x) {
        var dist = math.ceil((final_x - xpos)/5);
        xpos = xpos + dist;
      }
      if (xpos > final_x) {
        var dist = math.ceil((xpos - final_x)/5);
        xpos = xpos - dist;
      }
      elem.style.left = xpos + "px";
      var repeat = "moveelement('"+elementid+"',"+final_x+","+interval+")";
      elem.movement = settimeout(repeat,interval);
    }