Remove Resupply re-queueing hack from Aircraft

By preventing that other traits can remotely cancel Resupply
or ReturnToBase.

OpenRA.Mods.Common/Traits/Air/Aircraft.cs

@@ -672,23 +672,6 @@ void INotifyBecomingIdle.OnBecomingIdle(Actor self)
 
 		protected virtual void OnBecomingIdle(Actor self)
 		{
-			var altitude = self.World.Map.DistanceAboveTerrain(CenterPosition);
-			var atLandAltitude = altitude == LandAltitude;
-
-			// Work-around to prevent players from accidentally canceling resupply by pressing 'Stop',
-			// by re-queueing Resupply as long as resupply hasn't finished and aircraft is still on resupplier.
-			// TODO: Investigate moving this back to ResolveOrder's "Stop" handling,
-			// once conflicts with other traits' "Stop" orders have been fixed.
-			if (atLandAltitude)
-			{
-				var host = GetActorBelow();
-				if (host != null && (CanRearmAt(host) || CanRepairAt(host)))
-				{
-					self.QueueActivity(new Resupply(self, host, new WDist(512)));
-					return;
-				}
-			}
-
 			if (Info.IdleBehavior == IdleBehaviorType.LeaveMap)
 			{
 				self.QueueActivity(new FlyOffMap(self));
@@ -698,16 +681,17 @@ protected virtual void OnBecomingIdle(Actor self)
 				self.QueueActivity(new ReturnToBase(self, null, !Info.TakeOffOnResupply));
 			else
 			{
-				if (atLandAltitude)
+				var dat = self.World.Map.DistanceAboveTerrain(CenterPosition);
+				if (dat == LandAltitude)
 				{
 					if (!CanLand(self.Location) && ReservedActor == null)
 						self.QueueActivity(new TakeOff(self));
 
-					// All remaining idle behaviors rely on not being atLandAltitude, so unconditionally return
+					// All remaining idle behaviors rely on not being at LandAltitude, so unconditionally return
 					return;
 				}
 
-				if (Info.IdleBehavior != IdleBehaviorType.Land && altitude != Info.CruiseAltitude)
+				if (Info.IdleBehavior != IdleBehaviorType.Land && dat != Info.CruiseAltitude)
 					self.QueueActivity(new TakeOff(self));
 				else if (Info.IdleBehavior == IdleBehaviorType.Land && Info.LandableTerrainTypes.Count > 0)
 					self.QueueActivity(new Land(self));
@@ -1031,13 +1015,13 @@ public void ResolveOrder(Actor self, Order order)
 			}
 			else if (orderString == "Stop")
 			{
-				self.CancelActivity();
-
-				// HACK: If the player accidentally pressed 'Stop', we don't want this to cancel reservation.
-				// If unreserving is actually desired despite an actor below, it should be triggered from OnBecomingIdle.
-				if (GetActorBelow() != null)
+				// We don't want the Stop order to cancel a running Resupply activity.
+				// Resupply is always either the main activity or a child of ReturnToBase.
+				if (self.CurrentActivity is Resupply ||
+					(self.CurrentActivity is ReturnToBase && GetActorBelow() != null))
 					return;
 
+				self.CancelActivity();
 				UnReserve();
 			}
 			else if (orderString == "ReturnToBase" && rearmable != null && rearmable.Info.RearmActors.Any())

OpenRA.Mods.Common/Traits/Attack/AttackBase.cs

@@ -13,6 +13,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using OpenRA.Activities;
+using OpenRA.Mods.Common.Activities;
 using OpenRA.Mods.Common.Warheads;
 using OpenRA.Primitives;
 using OpenRA.Support;
@@ -206,6 +207,12 @@ void IResolveOrder.ResolveOrder(Actor self, Order order)
 		// Some 3rd-party mods rely on this being public
 		public virtual void OnStopOrder(Actor self)
 		{
+			// We don't want Stop orders from traits other than Mobile or Aircraft to cancel Resupply activity.
+			// Resupply is always either the main activity or a child of ReturnToBase.
+			// TODO: This should generally only cancel activities queued by this trait.
+			if (self.CurrentActivity == null || self.CurrentActivity is Resupply || self.CurrentActivity is ReturnToBase)
+				return;
+
 			self.CancelActivity();
 		}
 

OpenRA.Mods.Common/Traits/Buildings/TransformsIntoMobile.cs

@@ -116,9 +116,16 @@ void IResolveOrder.ResolveOrder(Actor self, Order order)
 				if (currentTransform == null)
 					self.QueueActivity(order.Queued, activity);
 			}
+			else if (order.OrderString == "Stop")
+			{
+				// We don't want Stop orders from traits other than Mobile or Aircraft to cancel Resupply activity.
+				// Resupply is always either the main activity or a child of ReturnToBase.
+				// TODO: This should generally only cancel activities queued by this trait.
+				if (self.CurrentActivity == null || self.CurrentActivity is Resupply || self.CurrentActivity is ReturnToBase)
+					return;
 
-			if (order.OrderString == "Stop")
 				self.CancelActivity();
+			}
 		}
 
 		string IOrderVoice.VoicePhraseForOrder(Actor self, Order order)

OpenRA.Mods.Common/Traits/Mobile.cs

@@ -802,6 +802,7 @@ void IResolveOrder.ResolveOrder(Actor self, Order order)
 				self.QueueActivity(order.Queued, WrapMove(new Move(self, cell, WDist.FromCells(8), null, true)));
 			}
 
+			// TODO: This should only cancel activities queued by this trait
 			if (order.OrderString == "Stop")
 				self.CancelActivity();