Fix air unit resupply #5966

AUTHORS

@@ -105,6 +105,7 @@ Also thanks to:
     * Paolo Chiodi (paolochiodi)
     * Paul Dovydaitis (pdovy)
     * Pavlos Touboulidis (pav)
+    * Pedro Ferreira Ramos (bateramos)
     * Pizzaoverhead
     * Piët Delport (pjdelport)
     * Psydev

OpenRA.Mods.Common/Activities/Air/FlyAttack.cs

@@ -41,7 +41,7 @@ namespace OpenRA.Mods.Common.Activities
 			// Move to the next activity only if all ammo pools are depleted and none reload automatically
 			// TODO: This should check whether there is ammo left that is actually suitable for the target
 			if (ammoPools.All(x => !x.Info.SelfReloads && !x.HasAmmo()))
-				return NextActivity;
+				return ActivityUtils.SequenceActivities(new ReturnToBase(self), NextActivity);
 
 			if (attackPlane != null)
 				attackPlane.DoAttack(self, target);

OpenRA.Mods.Common/Activities/Air/FlyCircleTimed.cs

@@ -0,0 +1,36 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2016 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, either version 3 of
+ * the License, or (at your option) any later version. For more
+ * information, see COPYING.
+ */
+#endregion
+
+using OpenRA.Activities;
+using OpenRA.Mods.Common.Traits;
+
+namespace OpenRA.Mods.Common.Activities
+{
+	public class FlyCircleTimed : FlyCircle
+	{
+		int remainingTicks;
+
+		public FlyCircleTimed(int ticks, Actor self) : base(self)
+		{
+			remainingTicks = ticks;
+		}
+
+		public override Activity Tick(Actor self)
+		{
+			if (IsCanceled || remainingTicks-- == 0)
+				return NextActivity;
+
+			base.Tick(self);
+
+			return this;
+		}
+	}
+}

OpenRA.Mods.Common/Activities/Air/HeliReturnToBase.cs

@@ -50,7 +50,22 @@ namespace OpenRA.Mods.Common.Activities
 				if (nearestHpad == null)
 					return ActivityUtils.SequenceActivities(new Turn(self, initialFacing), new HeliLand(self, true), NextActivity);
 				else
-					return ActivityUtils.SequenceActivities(new HeliFly(self, Target.FromActor(nearestHpad)));
+				{
+					var distanceFromHelipad = (nearestHpad.CenterPosition - self.CenterPosition).HorizontalLength;
+					var distanceLength = heli.Info.WaitDistanceFromResupplyBase.Length;
+
+					// If no pad is available, move near one and wait
+					if (distanceFromHelipad > distanceLength)
+					{
+						var randomPosition = WVec.FromPDF(self.World.SharedRandom, 2) * distanceLength / 1024;
+
+						var target = Target.FromPos(nearestHpad.CenterPosition + randomPosition);
+
+						return ActivityUtils.SequenceActivities(new HeliFly(self, target, WDist.Zero, heli.Info.WaitDistanceFromResupplyBase), this);
+					}
+
+					return this;
+				}
 			}
 
 			heli.MakeReservation(dest);
@@ -62,7 +77,8 @@ namespace OpenRA.Mods.Common.Activities
 				new HeliFly(self, Target.FromPos(dest.CenterPosition + offset)),
 				new Turn(self, initialFacing),
 				new HeliLand(self, false),
-				new ResupplyAircraft(self));
+				new ResupplyAircraft(self),
+				NextActivity);
 		}
 	}
 }

OpenRA.Mods.Common/Activities/Air/ResupplyAircraft.cs

@@ -32,8 +32,17 @@ namespace OpenRA.Mods.Common.Activities
 			if (host == null)
 				return NextActivity;
 
+			if (aircraft.IsPlane)
 				return ActivityUtils.SequenceActivities(
-				aircraft.GetResupplyActivities(host).Append(NextActivity).ToArray());
+					aircraft.GetResupplyActivities(host)
+					.Append(new CallFunc(() => aircraft.UnReserve()))
+					.Append(new WaitFor(() => NextActivity != null || Reservable.IsReserved(host)))
+					.Append(new TakeOff(self))
+					.Append(NextActivity).ToArray());
+
+			// If is helicopter move away as soon as the resupply ends
+			return ActivityUtils.SequenceActivities(
+				aircraft.GetResupplyActivities(host).Append(new TakeOff(self)).Append(NextActivity).ToArray());
 		}
 	}
 }

OpenRA.Mods.Common/Activities/Air/ReturnToBase.cs

@@ -106,11 +106,13 @@ namespace OpenRA.Mods.Common.Activities
 			{
 				var nearestAfld = ChooseAirfield(self, false);
 
-				self.CancelActivity();
 				if (nearestAfld != null)
-					return ActivityUtils.SequenceActivities(new Fly(self, Target.FromActor(nearestAfld)), new FlyCircle(self));
+					return ActivityUtils.SequenceActivities(
+						new Fly(self, Target.FromActor(nearestAfld), WDist.Zero, plane.Info.WaitDistanceFromResupplyBase),
+						new FlyCircleTimed(plane.Info.NumberOfTicksToVerifyAvailableAirport, self),
+						this);
 				else
-					return new FlyCircle(self);
+					return NextActivity;
 			}
 
 			List<Activity> landingProcedures = new List<Activity>();
@@ -123,6 +125,7 @@ namespace OpenRA.Mods.Common.Activities
 			// Fix a problem when the airplane is send to resupply near the airport
 			landingProcedures.Add(new Fly(self, Target.FromPos(w3), WDist.Zero, new WDist(turnRadius / 2)));
 			landingProcedures.Add(new Land(self, Target.FromActor(dest)));
+			landingProcedures.Add(new ResupplyAircraft(self));
 			landingProcedures.Add(NextActivity);
 
 			return ActivityUtils.SequenceActivities(landingProcedures.ToArray());

OpenRA.Mods.Common/OpenRA.Mods.Common.csproj

@@ -774,6 +774,7 @@
     <Compile Include="Traits\Buildings\FreeActorWithDelivery.cs" />
     <Compile Include="Traits\ExitsDebugOverlay.cs" />
     <Compile Include="Traits\World\ExitsDebugOverlayManager.cs" />
+    <Compile Include="Activities\Air\FlyCircleTimed.cs" />
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <PropertyGroup>

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

@@ -83,6 +83,12 @@ namespace OpenRA.Mods.Common.Traits
 		[Desc("Sound to play when the actor is landing.")]
 		public readonly string LandingSound = null;
 
+		[Desc("The distance of the resupply base that the aircraft will wait for its turn.")]
+		public readonly WDist WaitDistanceFromResupplyBase = new WDist(3072);
+
+		[Desc("The number of ticks that a airplane will wait to make a new search for an available airport.")]
+		public readonly int NumberOfTicksToVerifyAvailableAirport = 150;
+
 		public IReadOnlyDictionary<CPos, SubCell> OccupiedCells(ActorInfo info, CPos location, SubCell subCell = SubCell.Any) { return new ReadOnlyDictionary<CPos, SubCell>(); }
 		bool IOccupySpaceInfo.SharesCell { get { return false; } }
 	}
@@ -98,6 +104,7 @@ namespace OpenRA.Mods.Common.Traits
 
 		UpgradeManager um;
 		IDisposable reservation;
+		Actor reservedActor;
 		IEnumerable<int> speedModifiers;
 
 		[Sync] public int Facing { get; set; }
@@ -181,6 +188,13 @@ namespace OpenRA.Mods.Common.Traits
 			if (!Info.Repulsable)
 				return WVec.Zero;
 
+			if (reservation != null)
+			{
+				var distanceFromReservationActor = (reservedActor.CenterPosition - self.CenterPosition).HorizontalLength;
+				if (distanceFromReservationActor < Info.WaitDistanceFromResupplyBase.Length)
+					return WVec.Zero;
+			}
+
 			// Repulsion only applies when we're flying!
 			var altitude = self.World.Map.DistanceAboveTerrain(CenterPosition).Length;
 			if (altitude != Info.CruiseAltitude.Length)
@@ -261,7 +275,10 @@ namespace OpenRA.Mods.Common.Traits
 			UnReserve();
 			var reservable = target.TraitOrDefault<Reservable>();
 			if (reservable != null)
+			{
 				reservation = reservable.Reserve(target, self, this);
+				reservedActor = target;
+			}
 		}
 
 		public void UnReserve()
@@ -271,6 +288,8 @@ namespace OpenRA.Mods.Common.Traits
 
 			reservation.Dispose();
 			reservation = null;
+			reservedActor = null;
+
 			if (self.World.Map.DistanceAboveTerrain(CenterPosition).Length <= Info.LandAltitude.Length)
 				self.QueueActivity(new TakeOff(self));
 		}