var __ua__ = navigator.userAgent.toLowerCase();
   
   var qsoft = { 
        
        version : 0.35,
        prefx : 'qsoft',
        __id : 0,
        
        isIE : __ua__.indexOf("msie") > -1,
        isIE6 : __ua__.indexOf("msie 6") > -1,
        isIE7 : __ua__.indexOf("msie 7") > -1,
        
        nextId : function ()
        {
            return this.prefx + this.__id++;
        } 
    }
    
    if(qsoft.isIE6)
    {
        try{
            document.execCommand("BackgroundImageCache", false, true);
        }catch(e){}
    }
    
    ///origImage 可以作为一个图片对象，也可以作为名称ID字符串传入
    ///dx横向偏移量
    ///dy纵向偏移量
    qsoft.PopBigImage = function (origImage,dx,dy,mx,my)
    {
        var type = typeof(origImage);
        if(type.toLowerCase() == "string")
            this.oim = document.getElementById(origImage);
        else
            this.oim = origImage;
            
        if(typeof(this.oim.pbi) != "undefined")
            return this.oim.pbi;
            
        this.id = qsoft.nextId();
        this.oim.__maskid = this.id;
        this.oim.style.cursor = "move";
        
        this.ow = this.oim.width;
        this.oh = this.oim.height;
        
        this.detaX = (typeof(dx) == "undefined")?30 : dx;
        this.detaY = (typeof(dy) == "undefined")?0 : dy;
        
        this.getPos = function(o) 
        {
            var x = 0, y = 0;
            do{ x += o.offsetLeft;y += o.offsetTop;}while((o=o.offsetParent));
            return {left:x+document.body.scrollLeft,top:y+document.body.scrollTop}; 
        }

        var rect = this.getPos(this.oim); 
        this.ol = rect.left + this.detaX + this.ow ;//- (qsoft.isIE ?2:0);
        this.ot = rect.top + this.detaY;// - (qsoft.isIE ?2:0);
        
        this.src = this.oim.src;
        
        this.getImageSize = function (img)
        {
            var im = new Image();
            im.src = img.src;
            
            var size = {};
            size.width = im.width;
            size.height = im.height;
            
            im = null;
            delete im;
            
            return size;
        }
           
        var rsize = this.getImageSize(this.oim);
        this.w = rsize.width;
        this.h = rsize.height;
        
        this.maskX = (typeof(mx) == "undefined")? this.ow : mx;
        this.maskY = (typeof(my) == "undefined")? this.oh : my;
        if(this.maskX < 1) 
            this.maskX = Math.ceil(this.w * this.maskX); 
        else if (this.maskX < 10) 
            this.maskX = Math.ceil(this.ow * this.maskX);
        if(this.maskY < 1) 
            this.maskY = Math.ceil(this.h * this.maskY); 
        else if (this.maskY < 10) 
            this.maskY = Math.ceil(this.oh * this.maskY);  
        this.maskX = this.maskX < this.ow ? this.ow : this.maskX ;
        this.maskY = this.maskY < this.oh ? this.oh : this.maskY ;
        this.maskX = this.maskX > this.w ? this.w : this.maskX ;
        this.maskY = this.maskY > this.h ? this.h : this.maskY ;
        
        var qObj = this;
        this.createMask = function ()
        {
            if(typeof(this.mask) == "undefined")
            {
                this.mask = document.createElement("div");
                this.mask.id = this.oim.__maskid + "_mask";
                this.mask.style.position  = "absolute";
                this.mask.style.width = this.maskX + "px";
                this.mask.style.height = this.maskY + "px";
                this.mask.style.left = this.ol + "px";
                this.mask.style.top = this.ot + "px";    
                this.mask.style.backgroundImage  = "url("+this.src+")";
                this.mask.style.backgroundRepeat = "no-repeat";     
                this.mask.style.display = "none";
                this.mask.style.border = "#e9e8e8 1px solid";
                this.mask.style.zIndex = 1000;  
                document.body.appendChild(this.mask);      
            }
        }
        
        this.regEvent = function ()
        {
            this.oim.onmousemove = function ()
            {

                var e = arguments[0] || window.event;
                var ct = e.target || e.srcElement;
                var sz = qObj.getPos(ct);
                var ox = qsoft.isIE ? e.offsetX: (e.pageX - sz.left);
                var oy = qsoft.isIE ? e.offsetY: (e.pageY - sz.top);
                var x = Math.ceil(ox * qObj.w/qObj.ow) - qObj.maskX/2;
                var y = Math.ceil(oy * qObj.h/qObj.oh) - qObj.maskY/2;
           
               if(x<0) x = 0;
               if(y<0) y = 0;
               var maxx = Math.ceil((qObj.w-qObj.maskX));
               var maxy = Math.ceil((qObj.h-qObj.maskY));
               if(x>maxx) x = maxx;
               if(y>maxy) y = maxy;
               qObj.mask.style.backgroundPosition = -x  + "px " + -y + "px"; 
 
            }

            this.oim.onmouseout = function ()
            {
                qObj.mask.style.display = "none";
            }
        
            this.oim.onmouseover = function ()
            {
                qObj.mask.style.display = "block";
            }
            
        }
        
        this.render = function ()
        {
            this.createMask();
            this.regEvent();
        } 
        
    }

    qsoft.PopBigImage.create  = function (origImage,dx,dy,mx,my,bflag)
    {
        var q = new qsoft.PopBigImage(origImage,dx,dy,mx,my);
        q.render();
        if(bflag)
            q.mask.style.display = "block";
        return q;
    }