using System;
using System.Collections.Generic;
using OpenRa.Game.Effects;
using OpenRa.Game.Support;

namespace OpenRa.Game
{
	class World
	{
		List<Actor> actors = new List<Actor>();
		List<IEffect> effects = new List<IEffect>();
		List<Action<World>> frameEndActions = new List<Action<World>>();

		public void Add(Actor a)
		{
			a.IsInWorld = true;
			actors.Add(a);
			ActorAdded(a);
		}

		public void Remove(Actor a)
		{
			a.IsInWorld = false;
			actors.Remove(a);
			ActorRemoved(a);
		}

		public void Add(IEffect b) { effects.Add(b); }
		public void Remove(IEffect b) { effects.Remove(b); }

		public void AddFrameEndTask( Action<World> a ) { frameEndActions.Add( a ); }

		public event Action<Actor> ActorAdded = _ => { };
		public event Action<Actor> ActorRemoved = _ => { };
		
		public void Tick()
		{
			foreach (var a in actors) a.Tick();
			foreach (var e in effects) e.Tick();

			Game.viewport.Tick();

			var acts = frameEndActions;
			frameEndActions = new List<Action<World>>();
			foreach (var a in acts) a(this);
		}

		public IEnumerable<Actor> Actors { get { return actors; } }
		public IEnumerable<IEffect> Effects { get { return effects; } }

		uint nextAID = 0;
		internal uint NextAID()
		{
			return nextAID++;
		}

		public int SyncHash()
		{
			using (new PerfSample("synchash"))
			{
				int ret = 0;
				foreach (var a in Actors)
					ret += (int)a.ActorID * Sync.CalculateSyncHash(a);

				return ret;
			}
		}
	}
}