Move Power out of Building and into its own trait

Conflicts:
	mods/ts/rules/structures.yaml

OpenRA.Mods.RA/Power.cs

@@ -0,0 +1,63 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2014 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 COPYING.
+ */
+#endregion
+
+using System;
+using OpenRA.Mods.RA.Buildings;
+using OpenRA.Traits;
+
+namespace OpenRA.Mods.RA
+{
+	public class PowerInfo : ITraitInfo
+	{
+		[Desc("If negative, it will drain power. If positive, it will provide power.")]
+		public readonly int Amount = 0;
+
+		[Desc("Scale power amount with the current health.")]
+		public readonly bool ScaleWithHealth = false;
+
+		public object Create(ActorInitializer init) { return new Power(init.self, this); }
+	}
+
+	public class Power : INotifyDamage, INotifyCapture
+	{
+		readonly PowerInfo info;
+		readonly Lazy<Health> health;
+		PowerManager playerPower;
+
+		public int CurrentPower
+		{
+			get
+			{
+				if (info.Amount <= 0 || health == null || !info.ScaleWithHealth)
+					return info.Amount;
+
+				return info.Amount * health.Value.HP / health.Value.MaxHP;
+			}
+		}
+
+		public Power(Actor self, PowerInfo info)
+		{
+			this.info = info;
+			health = Exts.Lazy(self.TraitOrDefault<Health>);
+			playerPower = self.Owner.PlayerActor.Trait<PowerManager>();
+		}
+
+		public void Damaged(Actor self, AttackInfo e)
+		{
+			if (info.ScaleWithHealth)
+				playerPower.UpdateActor(self, CurrentPower);
+		}
+
+		public void OnCapture(Actor self, Actor captor, Player oldOwner, Player newOwner)
+		{
+			 playerPower = newOwner.PlayerActor.Trait<PowerManager>();
+		}
+	}
+}