var DomLib = {

    addClass: function(element, name)
    {
        if (element)
        {
            if (element.className != "")
            {
                element.className += " " + name;
            }
            else
            {
                element.className = name;
            }
        }
    },

    removeClass: function(element, name)
    {
        if (element.className == element.className.replace(" ", "-"))
        {
            element.className = element.className.replace(name, "");
        }
        else
        {
            element.className = element.className.replace(" " + name, "");
        }
    },

    getElementsByClassName: function(oElm, strTagName, strClassName)
    {
        var arrElements = (strTagName == "*" && document.all)? document.all : oElm.getElementsByTagName(strTagName);
        var arrReturnElements = new Array();
        strClassName = strClassName.replace(/\-/g, "\\-");
        var oRegExp = new RegExp("(^|\\s)" + strClassName + "(\\s|$)");
        var oElement;
        for (var i = 0; i < arrElements.length; i++)
        {
            oElement = arrElements[i];
            if (oRegExp.test(oElement.className))
            {
                arrReturnElements.push(oElement);
            }
        }
        return (arrReturnElements)
    },


    getPageScroll: function()
    {
        var yScroll;
        if (self.pageYOffset)
        {
            yScroll = self.pageYOffset;
        }
        else if (document.documentElement && document.documentElement.scrollTop) // Explorer 6 Strict
        {
            yScroll = document.documentElement.scrollTop;
        }
        else if (document.body) // all other Explorers
        {
            yScroll = document.body.scrollTop;
        }
        arrayPageScroll = new Array('', yScroll);
        return arrayPageScroll;
    },


    getPageSize: function()
    {
        var xScroll, yScroll;

        if (window.innerHeight && window.scrollMaxY)
        {
            xScroll = document.body.scrollWidth;
            yScroll = window.innerHeight + window.scrollMaxY;
        }
        else if (document.body.scrollHeight > document.body.offsetHeight) // all but Explorer Mac
        {
            xScroll = document.body.scrollWidth;
            yScroll = document.body.scrollHeight;
        }
        else  // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
        {
            xScroll = document.body.offsetWidth;
            yScroll = document.body.offsetHeight;
        }

        var windowWidth, windowHeight;
        if (self.innerHeight) // all except Explorer
        {
            windowWidth = self.innerWidth;
            windowHeight = self.innerHeight;
        }
        else if (document.documentElement && document.documentElement.clientHeight)  // Explorer 6 Strict Mode
        {
            windowWidth = document.documentElement.clientWidth;
            windowHeight = document.documentElement.clientHeight;
        }
        else if (document.body) // other Explorers
        {
            windowWidth = document.body.clientWidth;
            windowHeight = document.body.clientHeight;
        }

        var pageHeight, pageWidth;
        // for small pages with total height less then height of the viewport
        if (yScroll < windowHeight)
        {
            pageHeight = windowHeight;
        }
        else
        {
            pageHeight = yScroll;
        }

        // for small pages with total width less then width of the viewport
        if (xScroll < windowWidth)
        {
            pageWidth = windowWidth;
        }
        else
        {
            pageWidth = xScroll;
        }
        var arrayPageSize = new Array(pageWidth, pageHeight, windowWidth, windowHeight);
        return arrayPageSize;
    }

}

var ActivityIndicator = Class.create();

ActivityIndicator.prototype = {
    initialize: function(owner, options)
    {
        var image;
        if (options && options.image)
        {
            image = "<img src=\"" + options.image + "\" alt=\"\" />";
        }
        else
        {
            image = "";
        }
        this.height = options.height || 150;
        this.width = options.width || 150;
        if (owner == "body")
        {
            arrayPageSize = DomLib.getPageSize();
            arrayPageScroll = DomLib.getPageScroll();
            var top = arrayPageScroll[1] + ((arrayPageSize[3] - 35 - this.height) / 2);
            var left = ((arrayPageSize[0] - 20 - this.width) / 2);
            owner = document.getElementsByTagName("body").item(0);
        }
        else
        {
            if ($(owner))
            {
                owner = $(owner);
            }
            element = owner;
            top = left = 0;
            do
            {
                top += element.offsetTop || 0;
                left += element.offsetLeft || 0;
                element = element.offsetParent;
            } while (element);

            left += owner.offsetWidth;
            top += owner.offsetHeight;
        }
        this.spinner = document.createElement("div");
        this.spinner.style.border = "1px solid #000000";
        this.spinner.style.background = "#FFFFFF";
        this.spinner.style.position = "absolute";
        this.spinner.style.zIndex = 1000;
        this.spinner.style.textAlign = "center";
        this.spinner.style.verticalAlign = "middle";

        this.spinner.innerHTML = "<br />" + image + "<br /><br /><strong>Loading...</strong>";
        this.spinner.style.width = this.width + "px";
        this.spinner.style.height = this.height + "px";
        this.spinner.style.top = top + "px";
        this.spinner.style.left = left + "px";
        this.spinner.id = "spinner";
        owner.insertBefore(this.spinner, owner.firstChild);
    },

    destroy: function()
    {
        Element.remove(this.spinner);
    }
}