/**
*  This file defines an EventManager for propagating events between loosely coupled components
*  and frames on a web page.  Note that IFRAMEs are handled transparently. This means that
*  if you call register or notify in an IFRAME, all events will be transparently propagated to 
*  and from the parent frame in the page.
*
* @author Jeff Tassin
*/


//load("questia.js"); questia.rhino = true;

questia.EventManager = function() {
	
	var _listeners = new Object();

	this.getComponentListeners = function( compName, bCreate ) {
		var listeners = _listeners[compName];
		if ( listeners == null ) {
			listeners = new Array();
			_listeners[compName] = listeners;
		}
		return listeners;
	}
	
	this.register = function( compName, msg, callBack ) {
	    if ( callBack == null ) {
	    	return;
	    }
		var compListeners = this.getComponentListeners( compName, true );
		var listenerObj = { component: compName, message: msg, notify: callBack }; 
		if(this.isRegistered(compName, msg,callBack)){
				//throw "Listener already registered for component: " + compName + "  message:" + msg;
				// ignore here.
		}	
		compListeners.push( listenerObj );
	}
	
	this.isRegistered = function( compName, msg, callBack ) {
		var compListeners = this.getComponentListeners( compName, true );
		for( var i=0; i < compListeners.length; i++ ) {
			if ( compListeners[i].message == msg && compListeners[i].notify == callBack ) {
				return true;
			}
		}	
	return false;
	}

	this.notify = function(srcElement, compName, msg, payload) {
	   if ( parent != self ) {
	       parent.questia.Events.notify( srcElement, compName, msg, payload );
	   } else {
	   	   this.notifyInternal(srcElement, compName, msg, payload);
	       for( var i=0; i < window.frames.length; i++ ) {
	           var iframe = window.frames[i];
	           if ( iframe.questia && iframe.questia.Events ) {
	             iframe.questia.Events.notifyInternal(srcElement, compName, msg, payload );
	           }
	       }
	   }
	}
	
	this.notifyInternal = function(srcElement, compName, msg, payload) {
		var notifyFunc = null;
	    //try {
			var evt = { source: srcElement, component: compName, message: msg, value:payload };
			var compListeners = this.getComponentListeners( compName, false );
			if ( compListeners ) {
				for( var i=0; i < compListeners.length; i++ ) {
				    try {
						if ( compListeners[i].message == msg || compListeners[i].message == '*' ) {
					    	notifyFunc = compListeners[i].notify;
 					        compListeners[i].notify( evt );
					    }
					} catch( err ) {
					  if ( questia.Dictionary.isDevelopment ) {
					      questia.Log( err.description );
			              questia.Log( 'notify failed: ' + notifyFunc + '   comp: ' + compName + '  msg: ' + msg + '  payload: ' + payload );		  
					  }			  
					}
				}
			}
	}


	this.remove = function( compName, msg, callBack ) {
	    if ( callBack == null ) {
	    	return;
	    }
		var compListeners = this.getComponentListeners( compName, false );
		if ( compListeners ) {
			for( i=0; i < compListeners.length; i++ ) {
				if ( compListeners[i].message == msg && compListeners[i].notify == callBack ) {
					compListeners.splice(i,1);
					return;
				}
			}
		}
	}
}
questia.Events = new questia.EventManager();