package org.osflash.signals
{

	/** 
	 * Allows the valueClasses to be set in MXML, e.g.
	 * <signals:Signal id="nameChanged">{[String, uint]}</signals:Signal>
	 */
	[DefaultProperty("valueClasses")]	
	
	/**
	 * Signal dispatches events to multiple listeners.
	 * It is inspired by C# events and delegates, and by
	 * <a target="_top" href="http://en.wikipedia.org/wiki/Signals_and_slots">signals and slots</a>
	 * in Qt.
	 * A Signal adds event dispatching functionality through composition and interfaces,
	 * rather than inheriting from a dispatcher.
	 * <br/><br/>
	 * Project home: <a target="_top" href="http://github.com/robertpenner/as3-signals/">http://github.com/robertpenner/as3-signals/</a>
	 */
	public class Signal extends OnceSignal implements ISignal
	{
		/**
		 * Creates a Signal instance to dispatch value objects.
		 * @param	valueClasses Any number of class references that enable type checks in dispatch().
		 * For example, new Signal(String, uint)
		 * would allow: signal.dispatch("the Answer", 42)
		 * but not: signal.dispatch(true, 42.5)
		 * nor: signal.dispatch()
		 *
		 * NOTE: In AS3, subclasses cannot call super.apply(null, valueClasses),
		 * but this constructor has logic to support super(valueClasses).
		 */
		public function Signal(...valueClasses)
		{
			// Cannot use super.apply(null, valueClasses), so allow the subclass to call super(valueClasses).
			valueClasses = (valueClasses.length == 1 && valueClasses[0] is Array) ? valueClasses[0]:valueClasses;
			
			super(valueClasses);
		}
		
		/**
		 * @inheritDoc
		 * @throws flash.errors.IllegalOperationError <code>IllegalOperationError</code>: You cannot addOnce() then add() the same listener without removing the relationship first.
		 * @throws ArgumentError <code>ArgumentError</code>: Given listener is <code>null</code>.
		 */
		public function add(listener:Function):ISlot
		{
			return registerListener(listener);
		}
	}
}