using System;
using System.Collections.Generic;

namespace DMX2
{

	public struct EventData
	{
		public string id;
		public byte value;
	}

	public interface IEventProvider
	{
		string MenuName{ get; }
		string[] GetEventList();		
		bool Bind (string eventId, IEventTarget target);
		void Unbind (string eventId, IEventTarget target);
		Gtk.Menu GetProviderSubMenu( Gtk.ButtonPressEventHandler handler );
	}

	public interface IEventTarget
	{
		bool FireEvent(EventData data);
	}

	public class EventManager
	{
		class eventBinding
		{
			private eventBinding(){}
			public eventBinding(string _id, IEventTarget _target, IEventProvider _provider){
				id=_id; 
				target=_target;
				provider=_provider;
			}
			public string id;
			public IEventTarget target;
			public IEventProvider provider;
		}

		List<eventBinding> bindings = new List<eventBinding>();
		List<IEventProvider> providers = new List<IEventProvider>();

		public EventManager ()
		{

		}

		public void RegisterProvider (IEventProvider prov)
		{
			providers.Add (prov);

			List<string> evList = new List<string>(prov.GetEventList());

			foreach (eventBinding b in bindings) {
				if(b.provider == null && evList.Contains(b.id))
				{
					prov.Bind(b.id,b.target);
					b.provider = prov;
				}
			}

		}

		public Gtk.Menu GetMenu ( Gtk.ButtonPressEventHandler handler )
		{
			Gtk.Menu menu = new Gtk.Menu();


			return menu;

		}



		public void UnregisterProvider (IEventProvider prov)
		{
			foreach (eventBinding b in bindings) 
				if(b.provider == prov)
					b.provider = null;
			providers.Remove(prov);
		}

		public bool Bind (string eventId, IEventTarget target)
		{

			foreach (IEventProvider prov in providers) {
				if (prov.Bind (eventId, target)) {
					bindings.Add(new eventBinding(eventId,target,prov));
					return true;
				}
			}
			bindings.Add(new eventBinding(eventId,target,null));
			return false;
		}

		eventBinding findBinding (string eventId, IEventTarget target)
		{
			foreach (eventBinding b in bindings) {
				if (b.id == eventId && b.target == target) {
					return b;
				}
			}
			return null;
		}

		public void Unbind (string eventId, IEventTarget target)
		{
			eventBinding b = findBinding(eventId,target);
			if(b==null)return;
			b.provider.Unbind(eventId,target);
			bindings.Remove (b);
		}
	}
}