var TabManager = Class.create({
  initialize: function() {
    this.tabs = new Array();
    this.selectedIndex = 0;
  },
  addTab: function(tab) {
    this.tabs.push(tab);
  },
  hideAll: function() {
    this.tabs.each(function(tab) {
      tab.element().hide();
      tab.tablink().removeClassName('active');
    });
  },
  selectTab: function(index) {
    this.selectedIndex = index;
    this.hideAll();
    this.tabs[index].element().show();
    this.tabs[index].tablink().addClassName('active');
  }, 
  next: function() { this.selectTab(this.selectedIndex+1); },
  previous: function() { this.selectTab(this.selectedIndex-1); }

});
var Tab = Class.create({
  initialize: function(id) {
    this.id = id;
  },
  element: function() {return $(this.id);},
  
  tablink: function() {return $(this.id + '_tablink');}
});