// Based on event:Selectors by Justin Palmer
// http://encytemedia.com/event-selectors/
//
// Usage:
//
// Event.addBehavior({
//      "selector:event" : function(event) { /* event handler.  this refers to the element. */ },
//      "selector" : function() { /* runs function on dom ready.  this refers to the element. */ }
//      ...
// });
//
// Multiple calls will add to exisiting rules.  Event.addBehavior.reassignAfterAjax and
// Event.addBehavior.autoTrigger can be adjusted to needs.
Event.addBehavior = function(rules) {
  var ab = this.addBehavior;
  Object.extend(ab.rules, rules);
  
  if (!ab.responderApplied) {
    Ajax.Responders.register({
      onComplete : function() { 
        if (Event.addBehavior.reassignAfterAjax) 
          setTimeout(function() { ab.reload() }, 10);
      }
    });
    ab.responderApplied = true;
  }
  
  if (ab.autoTrigger) {
    this.onReady(ab.load.bind(ab, rules));
  }
  
};

Event.delegate = function(rules) {
  return function(e) {
      var element = $(e.element());
      for (var selector in rules)
        if (element.match(selector)) return rules[selector].apply(this, $A(arguments));
    }
}

Object.extend(Event.addBehavior, {
  rules : {}, cache : [],
  reassignAfterAjax : false,
  autoTrigger : true,
  
  load : function(rules) {
    for (var selector in rules) {
      var observer = rules[selector];
      var sels = selector.split(',');
      sels.each(function(sel) {
        var parts = sel.split(/:(?=[a-z]+$)/), css = parts[0], event = parts[1];
        $$(css).each(function(element) {
          if (event) {
            observer = Event.addBehavior._wrapObserver(observer);
            $(element).observe(event, observer);
            Event.addBehavior.cache.push([element, event, observer]);
          } else {
            if (!element.$$assigned || !element.$$assigned.include(observer)) {
              if (observer.attach) observer.attach(element);
              
              else observer.call($(element));
              element.$$assigned = element.$$assigned || [];
              element.$$assigned.push(observer);
            }
          }
        });
      });
    }
  },
  
  unload : function() {
    this.cache.each(function(c) {
      Event.stopObserving.apply(Event, c);
    });
    this.cache = [];
  },
  
  reload: function() {
    var ab = Event.addBehavior;
    ab.unload(); 
    ab.load(ab.rules);
  },
  
  _wrapObserver: function(observer) {
    return function(event) {
      if (observer.call(this, event) === false) event.stop(); 
    }
  }
  
});

Event.observe(window, 'unload', Event.addBehavior.unload.bind(Event.addBehavior));

// A silly Prototype style shortcut for the reckless
$$$ = Event.addBehavior.bind(Event);

// Behaviors can be bound to elements to provide an object orientated way of controlling elements
// and their behavior.  Use Behavior.create() to make a new behavior class then use attach() to
// glue it to an element.  Each element then gets it's own instance of the behavior and any
// methods called onxxx are bound to the relevent event.
// 
// Usage:
// 
// var MyBehavior = Behavior.create({
//   onmouseover : function() { this.element.addClassName('bong') } 
// });
//
// Event.addBehavior({ 'a.rollover' : MyBehavior });
// 
// If you need to pass additional values to initialize use:
//
// Event.addBehavior({ 'a.rollover' : MyBehavior(10, { thing : 15 }) })
//
// You can also use the attach() method.  If you specify extra arguments to attach they get passed to initialize.
//
// MyBehavior.attach(el, values, to, init);
//
// Finally, the rawest method is using the new constructor normally:
// var draggable = new Draggable(element, init, vals);
//
// Each behaviour has a collection of all its instances in Behavior.instances
//
var Behavior = {
  create: function() {
    var parent = null, properties = $A(arguments);
    if (Object.isFunction(properties[0]))
      parent = properties.shift();

      var behavior = function() { 
        var behavior = arguments.callee;
        if (!this.initialize) {
          var args = $A(arguments);

          return function() {
            var initArgs = [this].concat(args);
            behavior.attach.apply(behavior, initArgs);
          };
        } else {
          var args = (arguments.length == 2 && arguments[1] instanceof Array) ? 
                      arguments[1] : Array.prototype.slice.call(arguments, 1);

          this.element = $(arguments[0]);
          this.initialize.apply(this, args);
          behavior._bindEvents(this);
          behavior.instances.push(this);
        }
      };

    Object.extend(behavior, Class.Methods);
    Object.extend(behavior, Behavior.Methods);
    behavior.superclass = parent;
    behavior.subclasses = [];
    behavior.instances = [];

    if (parent) {
      var subclass = function() { };
      subclass.prototype = parent.prototype;
      behavior.prototype = new subclass;
      parent.subclasses.push(behavior);
    }

    for (var i = 0; i < properties.length; i++)
      behavior.addMethods(properties[i]);

    if (!behavior.prototype.initialize)
      behavior.prototype.initialize = Prototype.emptyFunction;

    behavior.prototype.constructor = behavior;

    return behavior;
  },
  Methods : {
    attach : function(element) {
      return new this(element, Array.prototype.slice.call(arguments, 1));
    },
    _bindEvents : function(bound) {
      for (var member in bound)
        if (member.match(/^on(.+)/) && typeof bound[member] == 'function')
          bound.element.observe(RegExp.$1, Event.addBehavior._wrapObserver(bound[member].bindAsEventListener(bound)));
    }
  }
};