/*
Script: Class.js
	Contains the Class Function for easily creating, extending, and implementing reusable Classes.

License:
	MIT-style license.
*/

var Class = new Native({

	name: 'Class',

	initialize: function(properties){
		properties = properties || {};
		var klass = function(empty){
			for (var key in this) this[key] = $unlink(this[key]);
			for (var mutator in Class.Mutators){
				if (!this[mutator]) continue;
				Class.Mutators[mutator](this, this[mutator]);
				delete this[mutator];
			}

			this.constructor = klass;
			if (empty === $empty) return this;
			
			var self = (this.initialize) ? this.initialize.apply(this, arguments) : this;
			if (this.options && this.options.initialize) this.options.initialize.call(this);
			return self;
		};

		$extend(klass, this);
		klass.constructor = Class;
		klass.prototype = properties;
		return klass;
	}

});

Class.implement({

	implement: function(){
		Class.Mutators.Implements(this.prototype, Array.slice(arguments));
		return this;
	}

});

Class.Mutators = {
  
  Implements: function(self, klasses){
  	$splat(klasses).each(function(klass){
  		$extend(self, ($type(klass) == 'class') ? new klass($empty) : klass);
  	});
  },
  
  Extends: function(self, klass){
  	var instance = new klass($empty);
  	delete instance.parent;
  	delete instance.parentOf;

  	for (var key in instance){
  		var current = self[key], previous = instance[key];
  		if (current == undefined){
  			self[key] = previous;
  			continue;
  		}

  		var ctype = $type(current), ptype = $type(previous);
  		if (ctype != ptype) continue;

  		switch (ctype){
  			case 'function': 
  				// this code will be only executed if the current browser does not support function.caller (currently only opera).
  				// we replace the function code with brute force. Not pretty, but it will only be executed if function.caller is not supported.

  				if (!arguments.callee.caller) self[key] = eval('(' + String(current).replace(/\bthis\.parent\(\s*(\))?/g, function(full, close){
  					return 'arguments.callee._parent_.call(this' + (close || ', ');
  				}) + ')');

  				// end "opera" code
  				self[key]._parent_ = previous;
  			  break;
  			case 'object': self[key] = $merge(previous, current);
  		}

  	}

  	self.parent = function(){
  		return arguments.callee.caller._parent_.apply(this, arguments);
  	};

  	self.parentOf = function(descendant){
  		return descendant._parent_.apply(this, Array.slice(arguments, 1));
  	};
  }
  
};
