Support map-defined AI in the lobby.

OpenRA.Game/Map/MapPreview.cs

@@ -210,6 +210,9 @@ namespace OpenRA
 				Status = MapStatus.Unavailable;
 			}
 
+			// Note: multiple threads may try to access the value at the same time
+			// We rely on the thread-safety guarantees given by Lazy<T> to prevent race conitions.
+			// If you're thinking about replacing this, then you must be careful to keep this safe.
 			rules = Exts.Lazy(() =>
 			{
 				try

OpenRA.Game/Widgets/WidgetUtils.cs

@@ -249,8 +249,6 @@ namespace OpenRA.Widgets
 			return trimmed;
 		}
 
-		public static Action Once(Action a) { return () => { if (a != null) { a(); a = null; } }; }
-
 		public static string ChooseInitialMap(string initialUid)
 		{
 			if (string.IsNullOrEmpty(initialUid) || Game.ModData.MapCache[initialUid].Status != MapStatus.Available)

OpenRA.Mods.Common/Widgets/Logic/Lobby/LobbyLogic.cs

@@ -65,6 +65,8 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 		readonly LabelWidget chatLabel;
 		bool teamChat;
 
+		bool addBotOnMapLoad;
+
 		int lobbyChatUnreadMessages;
 		int globalChatLastReadMessages;
 		int globalChatUnreadMessages;
@@ -201,9 +203,9 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 					(orderManager.LobbyInfo.Slots.Values.All(s => !s.AllowBots) &&
 					orderManager.LobbyInfo.Slots.Count(s => !s.Value.LockTeam && orderManager.LobbyInfo.ClientInSlot(s.Key) != null) == 0);
 
-				var botNames = modRules.Actors["player"].TraitInfos<IBotInfo>().Select(t => t.Name);
 				slotsButton.OnMouseDown = _ =>
 				{
+					var botNames = Map.Rules.Actors["player"].TraitInfos<IBotInfo>().Select(t => t.Name);
 					var options = new Dictionary<string, IEnumerable<DropDownOption>>();
 
 					var botController = orderManager.LobbyInfo.Clients.FirstOrDefault(c => c.IsAdmin);
@@ -711,16 +713,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 
 			// Add a bot on the first lobbyinfo update
 			if (skirmishMode)
-			{
+				addBotOnMapLoad = true;
-				Game.LobbyInfoChanged += WidgetUtils.Once(() =>
-				{
-					var slot = orderManager.LobbyInfo.FirstEmptyBotSlot();
-					var bot = modRules.Actors["player"].TraitInfos<IBotInfo>().Select(t => t.Name).FirstOrDefault();
-					var botController = orderManager.LobbyInfo.Clients.FirstOrDefault(c => c.IsAdmin);
-					if (slot != null && bot != null)
-						orderManager.IssueOrder(Order.Command("slot_bot {0} {1} {2}".F(slot, botController.Index, bot)));
-				});
-			}
 		}
 
 		public override void Tick()
@@ -796,6 +789,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				var currentMap = Map;
 				new Task(() =>
 				{
+					// Force map rules to be loaded on this background thread
 					var unused = currentMap.Rules;
 					Game.RunAfterTick(() =>
 					{
@@ -806,6 +800,17 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 						// Tell the server that we have the map
 						if (!currentMap.InvalidCustomRules)
 							orderManager.IssueOrder(Order.Command("state {0}".F(Session.ClientState.NotReady)));
+
+						if (addBotOnMapLoad)
+						{
+							var slot = orderManager.LobbyInfo.FirstEmptyBotSlot();
+							var bot = currentMap.Rules.Actors["player"].TraitInfos<IBotInfo>().Select(t => t.Name).FirstOrDefault();
+							var botController = orderManager.LobbyInfo.Clients.FirstOrDefault(c => c.IsAdmin);
+							if (slot != null && bot != null)
+								orderManager.IssueOrder(Order.Command("slot_bot {0} {1} {2}".F(slot, botController.Index, bot)));
+
+							addBotOnMapLoad = false;
+						}
 					});
 				}).Start();
 			}
@@ -837,7 +842,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 						template = emptySlotTemplate.Clone();
 
 					if (Game.IsHost)
-						LobbyUtils.SetupEditableSlotWidget(template, slot, client, orderManager, modRules);
+						LobbyUtils.SetupEditableSlotWidget(this, template, slot, client, orderManager);
 					else
 						LobbyUtils.SetupSlotWidget(template, slot, client);
 
@@ -856,7 +861,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 					LobbyUtils.SetupClientWidget(template, client, orderManager, client.Bot == null);
 
 					if (client.Bot != null)
-						LobbyUtils.SetupEditableSlotWidget(template, slot, client, orderManager, modRules);
+						LobbyUtils.SetupEditableSlotWidget(this, template, slot, client, orderManager);
 					else
 						LobbyUtils.SetupEditableNameWidget(template, slot, client, orderManager);
 

OpenRA.Mods.Common/Widgets/Logic/Lobby/LobbyUtils.cs

@@ -38,7 +38,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			}
 		}
 
-		public static void ShowSlotDropDown(Ruleset rules, DropDownButtonWidget dropdown, Session.Slot slot,
+		public static void ShowSlotDropDown(LobbyLogic logic, DropDownButtonWidget dropdown, Session.Slot slot,
 			Session.Client client, OrderManager orderManager)
 		{
 			var options = new Dictionary<string, IEnumerable<SlotDropDownOption>>() { { "Slot", new List<SlotDropDownOption>()
@@ -50,7 +50,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			var bots = new List<SlotDropDownOption>();
 			if (slot.AllowBots)
 			{
-				foreach (var b in rules.Actors["player"].TraitInfos<IBotInfo>().Select(t => t.Name))
+				foreach (var b in logic.Map.Rules.Actors["player"].TraitInfos<IBotInfo>().Select(t => t.Name))
 				{
 					var bot = b;
 					var botController = orderManager.LobbyInfo.Clients.FirstOrDefault(c => c.IsAdmin);
@@ -303,13 +303,13 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			name.GetText = () => label;
 		}
 
-		public static void SetupEditableSlotWidget(Widget parent, Session.Slot s, Session.Client c, OrderManager orderManager, Ruleset rules)
+		public static void SetupEditableSlotWidget(LobbyLogic logic, Widget parent, Session.Slot s, Session.Client c, OrderManager orderManager)
 		{
 			var slot = parent.Get<DropDownButtonWidget>("SLOT_OPTIONS");
 			slot.IsVisible = () => true;
 			slot.IsDisabled = () => orderManager.LocalClient.IsReady;
 			slot.GetText = () => c != null ? c.Name : s.Closed ? "Closed" : "Open";
-			slot.OnMouseDown = _ => ShowSlotDropDown(rules, slot, s, c, orderManager);
+			slot.OnMouseDown = _ => ShowSlotDropDown(logic, slot, s, c, orderManager);
 
 			// Ensure Name selector (if present) is hidden
 			var name = parent.GetOrNull("NAME");