var authFormWindow = {

        form_window: null,
        overlay : null,
        form_window_id : "login-form-window",
        login_field_id : "auth-user-login",

        ShowLoginForm : function()
        {
                if (!this.form_window)
                {
                        this.form_window = document.getElementById(this.form_window_id);
                        if (!this.form_window)
                                return false;

                        try {document.body.appendChild(this.form_window);}
                        catch (e){}
                }

                this.form_window.style.display = "block";

                if (this.GetOpacityProperty())
                        this.CreateOverlay();

                var loginField = document.getElementById(this.login_field_id);
                if (loginField)
                {
                        loginField.focus();
                        loginField.select();
                }
                return false;
        },

        CloseLoginForm : function()
        {
                if (this.form_window)
                        this.form_window.style.display = "none";

                if (this.overlay)
                        this.overlay.style.display = "none";

                return false;
        },


        CreateOverlay : function()
        {
                if (!this.overlay)
                {
                        this.overlay = document.body.appendChild(document.createElement("DIV"));
                        this.overlay.className = "login-form-overlay";

                        var _this = this;
                        this.overlay.onclick = function() {_this.CloseLoginForm()};
                }

                var windowSize = this.GetWindowScrollSize();

                this.overlay.style.width = windowSize.scrollWidth + "px";
                this.overlay.style.height = windowSize.scrollHeight + "px";
                this.overlay.style.display = "block";
        },

        GetOpacityProperty : function()
        {
                if (typeof document.body.style.opacity == 'string')
                        return 'opacity';
                else if (typeof document.body.style.MozOpacity == 'string')
                        return 'MozOpacity';
                else if (typeof document.body.style.KhtmlOpacity == 'string')
                        return 'KhtmlOpacity';
                else if (document.body.filters && navigator.appVersion.match(/MSIE ([\d.]+);/)[1]>=5.5)
                        return 'filter';

                return false;
        },

        GetWindowScrollSize : function(pDoc)
        {
                var width, height;
                if (!pDoc)
                        pDoc = document;

                if ( (pDoc.compatMode && pDoc.compatMode == "CSS1Compat"))
                {
                        width = pDoc.documentElement.scrollWidth;
                        height = pDoc.documentElement.scrollHeight;
                }
                else
                {
                        if (pDoc.body.scrollHeight > pDoc.body.offsetHeight)
                                height = pDoc.body.scrollHeight;
                        else
                                height = pDoc.body.offsetHeight;

                        if (pDoc.body.scrollWidth > pDoc.body.offsetWidth ||
                                (pDoc.compatMode && pDoc.compatMode == "BackCompat") ||
                                (pDoc.documentElement && !pDoc.documentElement.clientWidth)
                        )
                                width = pDoc.body.scrollWidth;
                        else
                                width = pDoc.body.offsetWidth;
                }
                return {scrollWidth : width, scrollHeight : height};
        }
}

var authPreloadImages = ["close.gif", "auth-form-bg.gif"];

authPreloadImages = null;