Add a Fluent based translation system.

OpenRA.Game/Game.cs

@@ -408,6 +408,7 @@ namespace OpenRA
 				Console.WriteLine("\t{0}: {1} ({2})", mod.Key, mod.Value.Title, mod.Value.Version);
 
 			InitializeMod(modID, args);
+			Ui.InitializeTranslation();
 		}
 
 		public static void InitializeMod(string mod, Arguments args)

OpenRA.Game/Manifest.cs

@@ -72,7 +72,7 @@ namespace OpenRA
 		public readonly string[]
 			Rules, ServerTraits,
 			Sequences, ModelSequences, Cursors, Chrome, Assemblies, ChromeLayout,
-			Weapons, Voices, Notifications, Music, TileSets,
+			Weapons, Voices, Notifications, Music, Translations, TileSets,
 			ChromeMetrics, MapCompatibility, Missions, Hotkeys;
 
 		public readonly IReadOnlyDictionary<string, string> Packages;
@@ -141,6 +141,7 @@ namespace OpenRA
 			Voices = YamlList(yaml, "Voices");
 			Notifications = YamlList(yaml, "Notifications");
 			Music = YamlList(yaml, "Music");
+			Translations = YamlList(yaml, "Translations");
 			TileSets = YamlList(yaml, "TileSets");
 			ChromeMetrics = YamlList(yaml, "ChromeMetrics");
 			Missions = YamlList(yaml, "Missions");

OpenRA.Game/Map/Map.cs

@@ -21,6 +21,7 @@ using OpenRA.Graphics;
 using OpenRA.Primitives;
 using OpenRA.Support;
 using OpenRA.Traits;
+using OpenRA.Widgets;
 
 namespace OpenRA
 {
@@ -164,6 +165,7 @@ namespace OpenRA
 			new MapField("Bounds"),
 			new MapField("Visibility"),
 			new MapField("Categories"),
+			new MapField("Translations", required: false),
 			new MapField("LockPreview", required: false, ignoreIfValue: "False"),
 			new MapField("Players", "PlayerDefinitions"),
 			new MapField("Actors", "ActorDefinitions"),
@@ -189,6 +191,7 @@ namespace OpenRA
 		public Rectangle Bounds;
 		public MapVisibility Visibility = MapVisibility.Lobby;
 		public string[] Categories = { "Conquest" };
+		public string[] Translations;
 
 		public int2 MapSize { get; private set; }
 
@@ -246,6 +249,8 @@ namespace OpenRA
 		CellLayer<List<MPos>> inverseCellProjection;
 		CellLayer<byte> projectedHeight;
 
+		internal Translation Translation;
+
 		public static string ComputeUID(IReadOnlyPackage package)
 		{
 			// UID is calculated by taking an SHA1 of the yaml and binary data
@@ -418,6 +423,8 @@ namespace OpenRA
 
 			Rules.Sequences.Preload();
 
+			Translation = new Translation(Game.Settings.Player.Language, Translations, this);
+
 			var tl = new MPos(0, 0).ToCPos(this);
 			var br = new MPos(MapSize.X - 1, MapSize.Y - 1).ToCPos(this);
 			AllCells = new CellRegion(Grid.Type, tl, br);
@@ -1307,5 +1314,13 @@ namespace OpenRA
 
 			return false;
 		}
+
+		public string Translate(string key, IDictionary<string, object> args = null, string attribute = null)
+		{
+			if (Translation.GetFormattedMessage(key, args, attribute) == key)
+				return Ui.Translate(key, args, attribute);
+
+			return Translation.GetFormattedMessage(key, args, attribute);
+		}
 	}
 }

OpenRA.Game/OpenRA.Game.csproj

@@ -11,6 +11,7 @@
     <PackageReference Include="System.Runtime.Loader" Version="4.3.0" />
   </ItemGroup>
   <ItemGroup>
+    <PackageReference Include="Fluent.Net" Version="1.0.50" />
     <PackageReference Include="OpenRA-Eluant" Version="1.0.18" />
     <PackageReference Include="Mono.NAT" Version="3.0.1" />
     <PackageReference Include="SharpZipLib" Version="1.3.1" />

OpenRA.Game/Settings.cs

@@ -221,6 +221,7 @@ namespace OpenRA
 		public Color Color = Color.FromArgb(200, 32, 32);
 		public string LastServer = "localhost:1234";
 		public Color[] CustomColors = { };
+		public string Language = "en";
 	}
 
 	public class GameSettings

OpenRA.Game/Translation.cs

@@ -0,0 +1,121 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2020 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 System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using Fluent.Net;
+using Fluent.Net.RuntimeAst;
+using OpenRA.FileSystem;
+
+namespace OpenRA
+{
+	public class Translation
+	{
+		readonly IEnumerable<MessageContext> messageContexts;
+
+		public Translation(string language, string[] translations, IReadOnlyFileSystem fileSystem)
+		{
+			if (translations == null || !translations.Any())
+				return;
+
+			messageContexts = GetMessageContext(language, translations, fileSystem).ToList();
+		}
+
+		IEnumerable<MessageContext> GetMessageContext(string language, string[] translations, IReadOnlyFileSystem fileSystem)
+		{
+			var backfall = translations.Where(t => t.EndsWith("en.ftl"));
+			var paths = translations.Where(t => t.EndsWith(language + ".ftl"));
+			foreach (var path in paths.Concat(backfall))
+			{
+				var stream = fileSystem.Open(path);
+				using (var reader = new StreamReader(stream))
+				{
+					var options = new MessageContextOptions { UseIsolating = false };
+					var messageContext = new MessageContext(language, options);
+					var errors = messageContext.AddMessages(reader);
+					foreach (var error in errors)
+						Log.Write("debug", error.ToString());
+
+					yield return messageContext;
+				}
+			}
+		}
+
+		public string GetFormattedMessage(string key, IDictionary<string, object> args = null, string attribute = null)
+		{
+			if (key == null)
+				return "";
+
+			foreach (var messageContext in messageContexts)
+			{
+				var message = messageContext.GetMessage(key);
+				if (message != null)
+				{
+					if (string.IsNullOrEmpty(attribute))
+						return messageContext.Format(message, args);
+					else
+						return messageContext.Format(message.Attributes[attribute], args);
+				}
+			}
+
+			return key;
+		}
+
+		public string GetAttribute(string key, string attribute)
+		{
+			if (key == null)
+				return "";
+
+			foreach (var messageContext in messageContexts)
+			{
+				var message = messageContext.GetMessage(key);
+				if (message != null && message.Attributes != null && message.Attributes.ContainsKey(attribute))
+				{
+					var node = message.Attributes[attribute];
+					var stringLiteral = (StringLiteral)node;
+					return stringLiteral.Value;
+				}
+			}
+
+			return "";
+		}
+
+		// Adapted from Fluent.Net.SimpleExample.TranslationService by Mark Weaver
+		public static Dictionary<string, object> Arguments(string name, object value, params object[] args)
+		{
+			if (args.Length % 2 != 0)
+				throw new ArgumentException("Expected a comma separated list of name, value arguments"
+					+ "but the number of arguments is not a multiple of two", nameof(args));
+
+			var argumentDictionary = new Dictionary<string, object> { { name, value } };
+
+			for (var i = 0; i < args.Length; i += 2)
+			{
+				name = args[i] as string;
+				if (string.IsNullOrEmpty(name))
+				{
+					throw new ArgumentException("Expected the argument at index {0} to be a non-empty string".F(i),
+						nameof(args));
+				}
+
+				value = args[i + 1];
+				if (value == null)
+					throw new ArgumentNullException("args", "Expected the argument at index {0} to be a non-null value".F(i + 1));
+
+				argumentDictionary.Add(name, value);
+			}
+
+			return argumentDictionary;
+		}
+	}
+}

OpenRA.Game/Widgets/Widget.cs

@@ -32,6 +32,8 @@ namespace OpenRA.Widgets
 		public static Widget KeyboardFocusWidget;
 		public static Widget MouseOverWidget;
 
+		internal static Translation Translation;
+
 		public static void CloseWindow()
 		{
 			if (WindowList.Count > 0)
@@ -155,6 +157,27 @@ namespace OpenRA.Widgets
 			HandleInput(new MouseInput(MouseInputEvent.Move, MouseButton.None,
 				Viewport.LastMousePos, int2.Zero, Modifiers.None, 0));
 		}
+
+		public static void InitializeTranslation()
+		{
+			Translation = new Translation(Game.Settings.Player.Language, Game.ModData.Manifest.Translations, Game.ModData.DefaultFileSystem);
+		}
+
+		public static string Translate(string key, IDictionary<string, object> args = null, string attribute = null)
+		{
+			if (Translation == null)
+				return null;
+
+			return Translation.GetFormattedMessage(key, args, attribute);
+		}
+
+		public static string TranslationAttribute(string key, string attribute = null)
+		{
+			if (Translation == null)
+				return null;
+
+			return Translation.GetAttribute(key, attribute);
+		}
 	}
 
 	public class ChromeLogic : IDisposable

OpenRA.Mods.Common/Scripting/Global/UserInterfaceGlobal.cs

@@ -31,5 +31,10 @@ namespace OpenRA.Mods.Common.Scripting.Global
 			var c = color.HasValue ? color.Value : Color.White;
 			luaLabel.GetColor = () => c;
 		}
+
+		public string Translate(string text)
+		{
+			return Context.World.Map.Translate(text);
+		}
 	}
 }