/*
 * Fabtabulous! Simple tabs using Prototype
 * http://tetlaw.id.au/view/blog/fabtabulous-simple-tabs-using-prototype/
 * Andrew Tetlaw
 * version 2 2008-08-10
 * http://creativecommons.org/licenses/by-sa/2.5/
 */
var Fabtabs = Class.create({
  initialize : function(element,options) {
    var parent = this.element = $(element);
    this.options = Object.extend({
      hover: true,
      remotehover: false,
      anchorpolicy: 'allow-initial' // 'protect', 'allow', 'allow initial', 'disable'
    }, options || {});
    this.menu = this.element.select('a');
    this.hrefs = this.menu.map(function(elm){
      return elm.href.match(/#(\w.+)/) ? RegExp.$1 : null;
    }).compact();
    this.on(this.getInitialTab());
    var onLocal = function(event) {
      if(this.options.anchorpolicy !== 'allow'){ event.stop(); }
      var elm = event.findElement("a");
      this.activate(elm);
      if(this.options.anchorpolicy === 'protect') { window.location.hash = '.'+this.tabID(elm); }
    };
    var onRemote = function(event) {
      if(this.options.anchorpolicy !== 'allow'){ event.stop(); }
      var trig = event.findElement("a");
      this.activate(this.tabID(trig));
      if(this.options.anchorpolicy === 'protect') { window.location.hash = '.'+this.tabID(elm); }
    }
    this.element.observe('click', onLocal.bindAsEventListener(this));
    if(this.options.hover) {
      this.menu.each(function(elm){elm.observe('mouseover', onLocal.bindAsEventListener(this))}.bind(this));
    }
    var triggers = []; 
    this.hrefs.each(function(id){
      $$('a[href="#' + id + '"]').reject(function(elm){
        return elm.descendantOf(parent)
      }).each(function(trig){
        triggers.push(trig);
      });
    })
    triggers.each(function(elm){
      elm.observe('click', onRemote.bindAsEventListener(this));
      if(this.options.remotehover) {
        elm.observe('mouseover', onRemote.bindAsEventListener(this));
      }
    }.bind(this));
  },
  activate: function(elm) {
    if(typeof elm == 'string') {
      elm = this.element.select('a[href="#'+ elm +'"]')[0];
    }
    this.on(elm);
    this.menu.without(elm).each(this.off.bind(this));
  },
  off: function(elm) {
    $(elm).removeClassName('active-tab');
    $(this.tabID(elm)).removeClassName('active-tab-body');
  },
  on: function(elm) {
    $(elm).addClassName('active-tab');
    $(this.tabID(elm)).addClassName('active-tab-body');
  },
  tabID: function(elm) {
    return elm.href.match(this.re)[1];
  },
  getInitialTab: function() {
    if(this.options.anchorpolicy !== 'disable' && document.location.href.match(this.re)) {
      var hash = RegExp.$1;
      if(hash.substring(0,1) == "."){
        hash = hash.substring(1);
      }
      return this.element.select('a[href="#'+ hash +'"]')[0];
    } else {
      return this.menu.first();
    }
  },
  re: /#(\.?\w.+)/
});