function page_control() {
        this.settings = new Array();
};

page_control.prototype.init = function(settings) {
        this.settings = settings;
};

page_control.prototype.getParam = function(name, default_value) {
        var value = null;

        value = (typeof(this.settings[name]) == "undefined") ? default_value : this.settings[name];

        // Fix bool values
        if (value == "true" || value == "false")
                return (value == "true");

        return value;
};

page_control.prototype.displayTab = function(tab_id, panel_id, sys_id, idx) {
        var panelElm = document.getElementById(panel_id);
        var panelContainerElm = panelElm ? panelElm.parentNode : null;
        var tabElm = document.getElementById(tab_id);
        var tabContainerElm = tabElm ? tabElm.parentNode : null;
        var selectionClass = this.getParam('selection_class', 'current');

        if (tabElm && tabContainerElm) {
                var nodes = tabContainerElm.childNodes;

                // Hide all other tabs
                for (var i=0; i<nodes.length; i++) {
                        if (nodes[i].nodeName == "LI")
                                nodes[i].className = '';
                }

                // Show selected tab
                tabElm.className = 'current';
        }

        if (panelElm && panelContainerElm) {
                var nodes = panelContainerElm.childNodes;

                // Hide all other panels
                for (var i=0; i<nodes.length; i++) {
                        if (nodes[i].nodeName == "DIV")
                                nodes[i].className = 'page';
                }

                // Show selected panel
                panelElm.className = 'current';
        }

        var sysElm = document.getElementById(sys_id);
        if (sysElm) 
          sysElm.value = idx;

};

page_control.prototype.getAnchor = function() {
        var pos, url = document.location.href;

        if ((pos = url.lastIndexOf('#')) != -1)
                return url.substring(pos + 1);

        return "";
};

// Global instance
var page_controller = new page_control();