/**
* Licensed under the MIT license.  Use it for whatever you 
*	want to use it for.  I'd appreciate an email just to 
*	let me know you find it useful!  set117@yahoo.com
*
* Copyright (c) 2009 Shane Tomlinson, http://www.shanetomlinson.com
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following
* conditions:
* 
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
* 
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/

/**
* 
* Message - An observer/listener pattern for Javascript.
*	Usage: 
*	To bind a listener to a message on an object:
*		Message( object ).bind( message_name, callback );
*	To trigger all listeners bound on a message on an object:
*		Message( object ).trigger( message_name, data );
*	When calling a callback, it will be called in the contxt of the
*		object being registered upon.  The input parameters will be:
*		event, data1, data2, ..., dataN
*	Example:
*		var testObject = {};
*		Message( testObject ).bind( 'testmessage', function( event, value1, value2 )
*		{
*			alert( 'event: ' + event.message + ' value1: ' + value1 + ' value2: ' + value2 );
*		};
*		
*		Message( testObject ).trigger( 'testmessage, [ 'testvalue1', 'testvalue2' ] );
*/
Message = function( object )
{
  if( !object.__objectID )
  { // Gives the object an ID if it doesn't already have one.
    object.__objectID = ( Message.currID++ ).toString();
  } // end if

  // return an object that contains the functions that can be worked with.
  return {
    bind: function( message, callback )
    {
      var handlers = Message.messages[ message + object.__objectID ] = Message.messages[ object.__objectID + message ] || [];
      handlers.push( callback );
      return this;
    },

    trigger: function( message, data )
    {
      var handlers = Message.messages[ message + object.__objectID ];
      if( handlers )
      {	
	var event = { 
	  target: object,
	  type: message 
	};
	var callbackArgs = [ event ].concat( data || [] );
      
	// go through all the handlers and call them with the arguments list we made up.
	for( var index = 0, handler; handler = handlers[ index ]; ++index )
	{
	  handler.apply( object, callbackArgs );
	} // end for
      } // end if
      return this;
    }
  };
};

/**
* static variables used for the message processor.
*/
Message.messages = {};
Message.currID = 0;