var isie = (document.all) ? true : false;

var isie6 = isie && ([/msie (\d)\.0/i.exec(navigator.useragent)][0][1] == 6);


function each(list, fun){
    for (var i = 0, len = list.length; i < len; i++) { fun(list[i], i); }
};

var $ = function (id) {
    return "string" == typeof id ? document.getelementbyid(id) : id;
};

var class = {
create: function() {
    return function() {
      this.initialize.apply(this, arguments);
    }
}
}

object.extend = function(destination, source) {
for (var property in source) {
    destination[property] = source[property];
}
return destination;
}

function.prototype.bind = function(object) {
var __method = this, args = array.apply(null, arguments); args.shift();
return function() {
    return __method.apply(object, args);
}
}

var overlay = class.create();
overlay.prototype = {
initialize: function(overlay, options) {
    this.lay = $(overlay);//覆盖层
    
    //ie6设置覆盖层大小程序
    this._size = function(){};
    
    this.setoptions(options);
    
    this.color = this.options.color;
    this.opacity = parseint(this.options.opacity);
    this.zindex = parseint(this.options.zindex);
    
    this.set();
},
//设置默认属性
setoptions: function(options) {
    this.options = {//默认值
        color:        "#fff",//背景色
        opacity:    50,//透明度(0-100)
        zindex:        1000//层叠顺序
    };
    object.extend(this.options, options || {});
},
//创建
set: function() {
    this.lay.style.display = "none";
    this.lay.style.zindex = this.zindex;
    this.lay.style.left = this.lay.style.top = 0;
    
    if(isie6){
        this.lay.style.position = "absolute";
        this._size = function(){
            this.lay.style.width = math.max(document.documentelement.scrollwidth, document.documentelement.clientwidth) + "px";
            this.lay.style.height = math.max(document.documentelement.scrollheight, document.documentelement.clientheight) + "px";
        }.bind(this);
        //遮盖select
        this.lay.innerhtml = '<iframe style="position:absolute;top:0;left:0;width:100%;height:100%;filter:alpha(opacity=0);"></iframe>'
    } else {
        this.lay.style.position = "fixed";
        this.lay.style.width = this.lay.style.height = "100%";
    }
},
//显示
show: function() {
    //设置样式
    this.lay.style.backgroundcolor = this.color;
    //设置透明度
    if(isie){
        this.lay.style.filter = "alpha(opacity:" + this.opacity + ")";
    } else {
        this.lay.style.opacity = this.opacity / 100;
    }
    //兼容ie6
    if(isie6){ this._size(); window.attachevent("onresize", this._size); }
    
    this.lay.style.display = "block";
},
//关闭
close: function() {
    this.lay.style.display = "none";
    if(isie6){ window.detachevent("onresize", this._size); }
}
};



var lightbox = class.create();
lightbox.prototype = {
initialize: function(box, overlay, options) {
    
    this.box = $(box);//显示层
    
    this.overlay = new overlay(overlay, options);//覆盖层
    
    this.setoptions(options);
    
    this.fixed = !!this.options.fixed;
    this.over = !!this.options.over;
    this.center = !!this.options.center;
    this.onshow = this.options.onshow;
    
    this.box.style.zindex = this.overlay.zindex + 1;
    this.box.style.display = "none";
    
    //兼容ie6用的属性
    if(isie6){ this._top = this._left = 0; this._select = []; }
},
//设置默认属性
setoptions: function(options) {
    this.options = {//默认值
        fixed:        false,//是否固定定位
        over:        true,//是否显示覆盖层
        center:        false,//是否居中
        onshow:        function(){}//显示时执行
    };
    object.extend(this.options, options || {});
},
//兼容ie6的固定定位程序
_fixed: function(){
    var itop = document.documentelement.scrolltop - this._top + this.box.offsettop, ileft = document.documentelement.scrollleft - this._left + this.box.offsetleft;
    //居中时需要修正
    if(this.center){ itop += this.box.offsetheight / 2; ileft += this.box.offsetwidth / 2; }
    
    this.box.style.top = itop + "px"; this.box.style.left = ileft + "px";
    
    this._top = document.documentelement.scrolltop; this._left = document.documentelement.scrollleft;
},
//显示
show: function(options) {
    //固定定位
    if(this.fixed){
        if(isie6){
            //兼容ie6
            this.box.style.position = "absolute";
            this._top = document.documentelement.scrolltop; this._left = document.documentelement.scrollleft;
            window.attachevent("onscroll", this._fixed.bind(this));
        } else {
            this.box.style.position = "fixed";
        }
    } else {
        this.box.style.position = "absolute";
    }
    //覆盖层
    if(this.over){
        //显示覆盖层，覆盖层自带select隐藏
        this.overlay.show();
    } else {
        //ie6需要把不在box上的select隐藏
        if(isie6){
            this._select = [];
            var othis = this;
            each(document.getelementsbytagname("select"), function(o){
                if(othis.box.contains ? !othis.box.contains(o) : !(othis.box.comparedocumentposition(o) & 16)){
                    o.style.visibility = "hidden"; othis._select.push(o);
                }
            })
        }
    }
    
    this.box.style.display = "block";
    
    //居中
    if(this.center){
        this.box.style.top = this.box.style.left = "50%";
        //显示后才能获取
        var itop = - this.box.offsetheight / 2, ileft = - this.box.offsetwidth / 2;
        //ie6或不是固定定位要修正
        if(!this.fixed || isie6){ itop += document.documentelement.scrolltop; ileft += document.documentelement.scrollleft; }
        this.box.style.margintop = itop + "px"; this.box.style.marginleft = ileft + "px";
    }
    
    this.onshow();
},
//关闭
close: function() {
    this.box.style.display = "none";
    this.overlay.close();
    if(isie6){ window.detachevent("onscroll", this._fixed); each(this._select, function(o){ o.style.visibility = "visible"; }); }
}
};


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;
    }
};

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;
    }
};

if(!isie){
    htmlelement.prototype.__definegetter__("currentstyle", function () {
        return this.ownerdocument.defaultview.getcomputedstyle(this, null);
    });
}

//拖放程序
var drag = class.create();
drag.prototype = {
//拖放对象,触发对象
initialize: function(obj, drag, options) {
    var othis = this;
    
    this._obj = $(obj);//拖放对象
    this.drag = $(drag);//触发对象
    this._x = this._y = 0;//记录鼠标相对拖放对象的位置
    //事件对象(用于移除事件)
    this._fm = function(e){ othis.move(window.event || e); }
    this._fs = function(){ othis.stop(); }
    
    this.setoptions(options);
    
    this.limit = !!this.options.limit;
    this.mxleft = parseint(this.options.mxleft);
    this.mxright = parseint(this.options.mxright);
    this.mxtop = parseint(this.options.mxtop);
    this.mxbottom = parseint(this.options.mxbottom);
    this.mxcontainer = this.options.mxcontainer;
    
    this.onmove = this.options.onmove;
    this.lock = !!this.options.lock;
    
    this._obj.style.position = "absolute";
    addeventhandler(this.drag, "mousedown", function(e){ othis.start(window.event || e); });
},
//设置默认属性
setoptions: function(options) {
    this.options = {//默认值
        limit:            false,//是否设置限制(为true时下面参数有用,可以是负数)
        mxleft:            0,//左边限制
        mxright:        0,//右边限制
        mxtop:            10,//上边限制
        mxbottom:        0,//下边限制
        mxcontainer:    null,//指定限制在容器内
        onmove:            function(){},//移动时执行
        lock:            false//是否锁定
    };
    object.extend(this.options, options || {});
},
//准备拖动
start: function(oevent) {
    if(this.lock){ return; }
    //记录鼠标相对拖放对象的位置
    this._x = oevent.clientx - this._obj.offsetleft;
    this._y = oevent.clienty - this._obj.offsettop;
    //mousemove时移动 mouseup时停止
    addeventhandler(document, "mousemove", this._fm);
    addeventhandler(document, "mouseup", this._fs);
    //使鼠标移到窗口外也能释放
    if(isie){
        addeventhandler(this.drag, "losecapture", this._fs);
        this.drag.setcapture();
    }else{
        addeventhandler(window, "blur", this._fs);
    }
},
//拖动
move: function(oevent) {
    //判断是否锁定
    if(this.lock){ this.stop(); return; }
    //清除选择(ie设置捕获后默认带这个)
    window.getselection && window.getselection().removeallranges();
    //当前鼠标位置减去相对拖放对象的位置得到offset位置
    var ileft = oevent.clientx - this._x, itop = oevent.clienty - this._y;
    //设置范围限制
    if(this.limit){
        //如果设置了容器,因为容器大小可能会变化所以每次都要设
        if(!!this.mxcontainer){
            this.mxleft = this.mxtop = 0;
            this.mxright = this.mxcontainer.clientwidth;
            this.mxbottom = this.mxcontainer.clientheight;
        }
        //获取超出长度
        var iright = ileft + this._obj.offsetwidth - this.mxright, ibottom = itop + this._obj.offsetheight - this.mxbottom;
        //这里是先设置右边下边再设置左边上边,可能会不准确
        if(iright > 0) ileft -= iright;
        if(ibottom > 0) itop -= ibottom;
        if(this.mxleft > ileft) ileft = this.mxleft;
        if(this.mxtop > itop) itop = this.mxtop;
    }
    //设置位置
    //由于offset是把margin也算进去的所以要减去
    this._obj.style.left = ileft - (parseint(this._obj.currentstyle.marginleft) || 0) + "px";
    this._obj.style.top = itop - (parseint(this._obj.currentstyle.margintop) || 0) + "px";    
    //附加程序
    this.onmove();
},
//停止拖动
stop: function() {
    //移除事件
    removeeventhandler(document, "mousemove", this._fm);
    removeeventhandler(document, "mouseup", this._fs);
    if(isie){
        removeeventhandler(this.drag, "losecapture", this._fs);
        this.drag.releasecapture();
    }else{
        removeeventhandler(window, "blur", this._fs);
    }
}
};