#region Copyright & License Information
/*
 * Copyright 2007-2010 The OpenRA Developers (see AUTHORS)
 * This file is part of OpenRA, which is free software. It is made 
 * available to you under the terms of the GNU General Public License
 * as published by the Free Software Foundation. For more information,
 * see LICENSE.
 */
#endregion

using OpenRA.Traits;

namespace OpenRA.Mods.RA.Activities
{
	class CaptureBuilding : IActivity
	{
		Actor target;

		public CaptureBuilding(Actor target) { this.target = target; }

		public IActivity NextActivity { get; set; }

		public IActivity Tick(Actor self)
		{
			if (target == null || target.IsDead) return NextActivity;
			var damage = -self.Info.Traits.Get<EngineerCaptureInfo>().EngineerDamage;
			if (self.Owner.Stances[ target.Owner ] == Stance.Ally)
			{
				if (target.Health == target.Info.Traits.Get<OwnedActorInfo>().HP)
					return NextActivity;
				target.InflictDamage(self, damage, null);
			}
			else
			{
				if (target.Health - damage <= 0)
				{
					target.World.AddFrameEndTask(w =>
						{		// momentarily remove from world so the ownership queries don't get confused
							w.Remove(target);
							target.Owner = self.Owner;
							w.Add(target);
							
							foreach (var t in target.traits.WithInterface<INotifyCapture>())
								t.OnCapture(target, self);
						});

					target.InflictDamage(self, target.Health - damage, null);
				}
				else
					target.InflictDamage(self, damage, null);
			}

			// the engineer is sacrificed.
			self.World.AddFrameEndTask(w => w.Remove(self));

			return NextActivity;
		}

		public void Cancel(Actor self) { target = null; NextActivity = null; }
	}
}