Initial commit: OpenRA game engine

Fork from OpenRA/OpenRA with one-click launch script (start-ra.cmd)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

OpenRA.Mods.Common/Installer/Availability.cs

@@ -0,0 +1,20 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public enum Availability
+	{
+		Unavailable,
+		GameSource,
+		DigitalInstall
+	}
+}

OpenRA.Mods.Common/Installer/ISourceAction.cs

@@ -0,0 +1,21 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public interface ISourceAction
+	{
+		void RunActionOnSource(MiniYaml actionYaml, string path, ModData modData, List<string> extracted, Action<string> updateMessage);
+	}
+}

OpenRA.Mods.Common/Installer/ISourceResolver.cs

@@ -0,0 +1,19 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public interface ISourceResolver
+	{
+		string FindSourcePath(ModContent.ModSource modSource);
+		Availability GetAvailability();
+	}
+}

OpenRA.Mods.Common/Installer/InstallerUtils.cs

@@ -0,0 +1,80 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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.IO;
+using FS = OpenRA.FileSystem.FileSystem;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public static class InstallerUtils
+	{
+		public static bool IsValidSourcePath(string path, ModContent.ModSource source)
+		{
+			if (source.IDFiles == null)
+				return true;
+
+			try
+			{
+				foreach (var kv in source.IDFiles.Nodes)
+				{
+					var filePath = FS.ResolveCaseInsensitivePath(Path.Combine(path, kv.Key));
+					if (!File.Exists(filePath))
+						return false;
+
+					using (var fileStream = File.OpenRead(filePath))
+					{
+						var offsetNode = kv.Value.NodeWithKeyOrDefault("Offset");
+						var lengthNode = kv.Value.NodeWithKeyOrDefault("Length");
+						if (offsetNode != null || lengthNode != null)
+						{
+							var offset = 0L;
+							if (offsetNode != null)
+								offset = FieldLoader.GetValue<long>("Offset", offsetNode.Value.Value);
+
+							var length = fileStream.Length - offset;
+							if (lengthNode != null)
+								length = FieldLoader.GetValue<long>("Length", lengthNode.Value.Value);
+
+							fileStream.Position = offset;
+							var data = fileStream.ReadBytes((int)length);
+							if (CryptoUtil.SHA1Hash(data) != kv.Value.Value)
+								return false;
+						}
+						else if (CryptoUtil.SHA1Hash(fileStream) != kv.Value.Value)
+							return false;
+					}
+				}
+			}
+			catch (Exception)
+			{
+				return false;
+			}
+
+			return true;
+		}
+
+		public static void CopyStream(Stream input, Stream output, long length, Action<long> onProgress = null)
+		{
+			var buffer = new byte[4096];
+			var copied = 0L;
+			while (copied < length)
+			{
+				var read = (int)Math.Min(buffer.Length, length - copied);
+				var write = input.Read(buffer, 0, read);
+				output.Write(buffer, 0, write);
+				copied += write;
+
+				onProgress?.Invoke(copied);
+			}
+		}
+	}
+}

OpenRA.Mods.Common/Installer/SourceActions/CopySourceAction.cs

@@ -0,0 +1,59 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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 OpenRA.Mods.Common.Widgets.Logic;
+using FS = OpenRA.FileSystem.FileSystem;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class CopySourceAction : ISourceAction
+	{
+		public void RunActionOnSource(MiniYaml actionYaml, string path, ModData modData, List<string> extracted, Action<string> updateMessage)
+		{
+			var sourceDir = Path.Combine(path, actionYaml.Value);
+			foreach (var node in actionYaml.Nodes)
+			{
+				var sourcePath = FS.ResolveCaseInsensitivePath(Path.Combine(sourceDir, node.Value.Value));
+				var targetPath = Platform.ResolvePath(node.Key);
+				if (File.Exists(targetPath))
+				{
+					Log.Write("install", "Ignoring installed file " + targetPath);
+					continue;
+				}
+
+				Log.Write("install", $"Copying {sourcePath} -> {targetPath}");
+				extracted.Add(targetPath);
+				Directory.CreateDirectory(Path.GetDirectoryName(targetPath));
+
+				using (var source = File.OpenRead(sourcePath))
+				using (var target = File.OpenWrite(targetPath))
+				{
+					var displayFilename = Path.GetFileName(targetPath);
+					var length = source.Length;
+
+					Action<long> onProgress = null;
+					if (length < InstallFromSourceLogic.ShowPercentageThreshold)
+						updateMessage(FluentProvider.GetMessage(InstallFromSourceLogic.CopyingFilename,
+							"filename", displayFilename));
+					else
+						onProgress = b => updateMessage(FluentProvider.GetMessage(InstallFromSourceLogic.CopyingFilenameProgress,
+							"filename", displayFilename,
+							"progress", 100 * b / length));
+
+					InstallerUtils.CopyStream(source, target, length, onProgress);
+				}
+			}
+		}
+	}
+}

OpenRA.Mods.Common/Installer/SourceActions/DeleteSourceAction.cs

@@ -0,0 +1,32 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class DeleteSourceAction : ISourceAction
+	{
+		public void RunActionOnSource(MiniYaml actionYaml, string path, ModData modData, List<string> extracted, Action<string> updateMessage)
+		{
+			// Yaml path must be specified relative to a named directory (e.g. ^SupportDir)
+			if (!actionYaml.Value.StartsWith('^'))
+				return;
+
+			var sourcePath = Platform.ResolvePath(actionYaml.Value);
+
+			Log.Write("debug", $"Deleting {sourcePath}");
+			File.Delete(sourcePath);
+		}
+	}
+}

OpenRA.Mods.Common/Installer/SourceActions/ExtractBlastSourceAction.cs

@@ -0,0 +1,87 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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 OpenRA.Mods.Common.FileFormats;
+using OpenRA.Mods.Common.Widgets.Logic;
+using FS = OpenRA.FileSystem.FileSystem;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class ExtractBlastSourceAction : ISourceAction
+	{
+		public void RunActionOnSource(MiniYaml actionYaml, string path, ModData modData, List<string> extracted, Action<string> updateMessage)
+		{
+			// Yaml path may be specified relative to a named directory (e.g. ^SupportDir) or the detected source path
+			var sourcePath = actionYaml.Value.StartsWith('^')
+				? Platform.ResolvePath(actionYaml.Value)
+				: FS.ResolveCaseInsensitivePath(Path.Combine(path, actionYaml.Value));
+
+			using (var source = File.OpenRead(sourcePath))
+			{
+				source.Position = 12;
+				var numFiles = source.ReadUInt16();
+				source.Position = 51;
+				source.Position = source.ReadUInt32();
+
+				var entries = new Dictionary<string, (uint Length, uint Offset)>();
+
+				for (var i = 0; i < numFiles; i++)
+				{
+					source.Position += 7;
+					var entry = (source.ReadUInt32(), source.ReadUInt32());
+					source.Position += 14;
+					var key = source.ReadASCII(source.ReadByte());
+					source.Position += 13;
+
+					// This does not apply on game relevant data.
+					entries.TryAdd(key, entry);
+				}
+
+				foreach (var node in actionYaml.Nodes)
+				{
+					var targetPath = Platform.ResolvePath(node.Key);
+
+					if (File.Exists(targetPath))
+					{
+						Log.Write("install", "Skipping installed file " + targetPath);
+						continue;
+					}
+
+					var (length, offset) = entries[node.Value.Value];
+
+					source.Position = offset;
+
+					extracted.Add(targetPath);
+					Directory.CreateDirectory(Path.GetDirectoryName(targetPath));
+					var displayFilename = Path.GetFileName(Path.GetFileName(targetPath));
+
+					Action<long> onProgress = null;
+					if (length < InstallFromSourceLogic.ShowPercentageThreshold)
+						updateMessage(FluentProvider.GetMessage(InstallFromSourceLogic.Extracting,
+							"filename", displayFilename));
+					else
+						onProgress = b => updateMessage(FluentProvider.GetMessage(InstallFromSourceLogic.ExtractingProgress,
+							"filename", displayFilename,
+							"progress", 100 * b / length));
+
+					using (var target = File.OpenWrite(targetPath))
+					{
+						Log.Write("install", $"Extracting {sourcePath} -> {targetPath}");
+						Blast.Decompress(source, target, (read, _) => onProgress?.Invoke(read));
+					}
+				}
+			}
+		}
+	}
+}

OpenRA.Mods.Common/Installer/SourceActions/ExtractIscabSourceAction.cs

@@ -0,0 +1,82 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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 OpenRA.Mods.Common.FileFormats;
+using OpenRA.Mods.Common.Widgets.Logic;
+using FS = OpenRA.FileSystem.FileSystem;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class ExtractIscabSourceAction : ISourceAction
+	{
+		public void RunActionOnSource(MiniYaml actionYaml, string path, ModData modData, List<string> extracted, Action<string> updateMessage)
+		{
+			// Yaml path may be specified relative to a named directory (e.g. ^SupportDir) or the detected source path
+			var sourcePath = actionYaml.Value.StartsWith('^')
+				? Platform.ResolvePath(actionYaml.Value)
+				: FS.ResolveCaseInsensitivePath(Path.Combine(path, actionYaml.Value));
+
+			var volumeNode = actionYaml.NodeWithKeyOrDefault("Volumes");
+			if (volumeNode == null)
+				throw new InvalidDataException("extract-iscab entry doesn't define a Volumes node");
+
+			var extractNode = actionYaml.NodeWithKeyOrDefault("Extract");
+			if (extractNode == null)
+				throw new InvalidDataException("extract-iscab entry doesn't define an Extract node");
+
+			var volumes = new Dictionary<int, Stream>();
+			try
+			{
+				foreach (var node in volumeNode.Value.Nodes)
+				{
+					var volume = FieldLoader.GetValue<int>("(key)", node.Key);
+					var stream = File.OpenRead(FS.ResolveCaseInsensitivePath(Path.Combine(path, node.Value.Value)));
+					volumes.Add(volume, stream);
+				}
+
+				using (var source = File.OpenRead(sourcePath))
+				{
+					var reader = new InstallShieldCABCompression(source, volumes);
+					foreach (var node in extractNode.Value.Nodes)
+					{
+						var targetPath = Platform.ResolvePath(node.Key);
+
+						if (File.Exists(targetPath))
+						{
+							Log.Write("install", "Skipping installed file " + targetPath);
+							continue;
+						}
+
+						extracted.Add(targetPath);
+						Directory.CreateDirectory(Path.GetDirectoryName(targetPath));
+						using (var target = File.OpenWrite(targetPath))
+						{
+							Log.Write("install", $"Extracting {sourcePath} -> {targetPath}");
+							var displayFilename = Path.GetFileName(Path.GetFileName(targetPath));
+							void OnProgress(int percent) => updateMessage(FluentProvider.GetMessage(
+								InstallFromSourceLogic.ExtractingProgress,
+								"filename", displayFilename, "progress", percent));
+							reader.ExtractFile(node.Value.Value, target, OnProgress);
+						}
+					}
+				}
+			}
+			finally
+			{
+				foreach (var kv in volumes)
+					kv.Value.Dispose();
+			}
+		}
+	}
+}

OpenRA.Mods.Common/Installer/SourceActions/ExtractMscabSourceAction.cs

@@ -0,0 +1,58 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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 OpenRA.Mods.Common.FileFormats;
+using OpenRA.Mods.Common.Widgets.Logic;
+using FS = OpenRA.FileSystem.FileSystem;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class ExtractMscabSourceAction : ISourceAction
+	{
+		public void RunActionOnSource(MiniYaml actionYaml, string path, ModData modData, List<string> extracted, Action<string> updateMessage)
+		{
+			// Yaml path may be specified relative to a named directory (e.g. ^SupportDir) or the detected source path
+			var sourcePath = actionYaml.Value.StartsWith('^')
+				? Platform.ResolvePath(actionYaml.Value)
+				: FS.ResolveCaseInsensitivePath(Path.Combine(path, actionYaml.Value));
+
+			using (var source = File.OpenRead(sourcePath))
+			{
+				var reader = new MSCabCompression(source);
+				foreach (var node in actionYaml.Nodes)
+				{
+					var targetPath = Platform.ResolvePath(node.Key);
+
+					if (File.Exists(targetPath))
+					{
+						Log.Write("install", "Skipping installed file " + targetPath);
+						continue;
+					}
+
+					extracted.Add(targetPath);
+					Directory.CreateDirectory(Path.GetDirectoryName(targetPath));
+					using (var target = File.OpenWrite(targetPath))
+					{
+						Log.Write("install", $"Extracting {sourcePath} -> {targetPath}");
+						var displayFilename = Path.GetFileName(Path.GetFileName(targetPath));
+						void OnProgress(int percent) => updateMessage(FluentProvider.GetMessage(InstallFromSourceLogic.ExtractingProgress,
+							"filename", displayFilename,
+							"progress", percent));
+						reader.ExtractFile(node.Value.Value, target, OnProgress);
+					}
+				}
+			}
+		}
+	}
+}

OpenRA.Mods.Common/Installer/SourceActions/ExtractRawSourceAction.cs

@@ -0,0 +1,80 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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 OpenRA.Mods.Common.Widgets.Logic;
+using FS = OpenRA.FileSystem.FileSystem;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class ExtractRawSourceAction : ISourceAction
+	{
+		public void RunActionOnSource(MiniYaml actionYaml, string path, ModData modData, List<string> extracted, Action<string> updateMessage)
+		{
+			// Yaml path may be specified relative to a named directory (e.g. ^SupportDir) or the detected source path
+			var sourcePath = actionYaml.Value.StartsWith('^')
+				? Platform.ResolvePath(actionYaml.Value)
+				: FS.ResolveCaseInsensitivePath(Path.Combine(path, actionYaml.Value));
+
+			using (var source = File.OpenRead(sourcePath))
+			{
+				foreach (var node in actionYaml.Nodes)
+				{
+					var targetPath = Platform.ResolvePath(node.Key);
+
+					if (File.Exists(targetPath))
+					{
+						Log.Write("install", "Skipping installed file " + targetPath);
+						continue;
+					}
+
+					var offsetNode = node.Value.NodeWithKeyOrDefault("Offset");
+					if (offsetNode == null)
+					{
+						Log.Write("install", "Skipping entry with missing Offset definition " + targetPath);
+						continue;
+					}
+
+					var lengthNode = node.Value.NodeWithKeyOrDefault("Length");
+					if (lengthNode == null)
+					{
+						Log.Write("install", "Skipping entry with missing Length definition " + targetPath);
+						continue;
+					}
+
+					var length = FieldLoader.GetValue<int>("Length", lengthNode.Value.Value);
+					source.Position = FieldLoader.GetValue<int>("Offset", offsetNode.Value.Value);
+
+					extracted.Add(targetPath);
+					Directory.CreateDirectory(Path.GetDirectoryName(targetPath));
+					var displayFilename = Path.GetFileName(Path.GetFileName(targetPath));
+
+					Action<long> onProgress = null;
+					if (length < InstallFromSourceLogic.ShowPercentageThreshold)
+						updateMessage(FluentProvider.GetMessage(InstallFromSourceLogic.Extracting,
+							"filename", displayFilename));
+					else
+						onProgress = b => updateMessage(FluentProvider.GetMessage(InstallFromSourceLogic.ExtractingProgress,
+							"filename", displayFilename,
+							"progress", 100 * b / length));
+
+					using (var target = File.OpenWrite(targetPath))
+					{
+						Log.Write("install", $"Extracting {sourcePath} -> {targetPath}");
+						InstallerUtils.CopyStream(source, target, length, onProgress);
+					}
+				}
+			}
+		}
+	}
+}

OpenRA.Mods.Common/Installer/SourceActions/ExtractZipSourceAction.cs

@@ -0,0 +1,61 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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 ICSharpCode.SharpZipLib.Zip;
+using OpenRA.Mods.Common.Widgets.Logic;
+using FS = OpenRA.FileSystem.FileSystem;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class ExtractZipSourceAction : ISourceAction
+	{
+		public void RunActionOnSource(MiniYaml actionYaml, string path, ModData modData, List<string> extracted,
+			Action<string> updateMessage)
+		{
+			var zipPath = actionYaml.Value.StartsWith('^')
+				? Platform.ResolvePath(actionYaml.Value)
+				: FS.ResolveCaseInsensitivePath(Path.Combine(path, actionYaml.Value));
+
+			using (var zipFile = new ZipFile(File.OpenRead(zipPath)))
+			{
+				foreach (var node in actionYaml.Nodes)
+				{
+					var targetPath = Platform.ResolvePath(node.Key);
+					var sourcePath = node.Value.Value;
+					var displayFilename = Path.GetFileName(targetPath);
+
+					if (File.Exists(targetPath))
+					{
+						Log.Write("install", "Skipping installed file " + targetPath);
+						continue;
+					}
+
+					Log.Write("install", $"Extracting {sourcePath} -> {targetPath}");
+
+					Directory.CreateDirectory(Path.GetDirectoryName(targetPath));
+
+					var sourceStream = zipFile.GetInputStream(zipFile.GetEntry(sourcePath));
+					using (var targetStream = File.OpenWrite(targetPath))
+						sourceStream.CopyTo(targetStream);
+
+					updateMessage(FluentProvider.GetMessage(InstallFromSourceLogic.ExtractingProgress,
+						"filename", displayFilename,
+						"progress", 100));
+
+					extracted.Add(targetPath);
+				}
+			}
+		}
+	}
+}

OpenRA.Mods.Common/Installer/SourceResolvers/DiscSourceResolver.cs

@@ -0,0 +1,60 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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.IO;
+using System.Linq;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class DiscSourceResolver : ISourceResolver
+	{
+		public string FindSourcePath(ModContent.ModSource source)
+		{
+			var volumes = DriveInfo.GetDrives()
+				.Where(d =>
+				{
+					if (d.DriveType == DriveType.CDRom && d.IsReady)
+						return true;
+
+					// HACK: the "TFD" DVD is detected as a fixed udf-formatted drive on OSX
+					if (d.DriveType == DriveType.Fixed && d.DriveFormat == "udf")
+						return true;
+
+					return false;
+				})
+				.Select(v => v.RootDirectory.FullName);
+
+			if (Platform.CurrentPlatform == PlatformType.Linux)
+			{
+				// Outside of Gnome, most mounting tools on Linux don't set DriveType.CDRom
+				// so provide a fallback by allowing users to manually mount images on known paths
+				volumes = volumes.Concat(
+				[
+					"/media/openra",
+					"/media/" + Environment.UserName + "/openra",
+					"/mnt/openra"
+				]);
+			}
+
+			foreach (var volume in volumes)
+				if (InstallerUtils.IsValidSourcePath(volume, source))
+					return volume;
+
+			return null;
+		}
+
+		public Availability GetAvailability()
+		{
+			return Availability.GameSource;
+		}
+	}
+}

OpenRA.Mods.Common/Installer/SourceResolvers/GogSourceResolver.cs

@@ -0,0 +1,53 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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.Runtime.InteropServices;
+using Microsoft.Win32;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class GogSourceResolver : ISourceResolver
+	{
+		public string FindSourcePath(ModContent.ModSource modSource)
+		{
+			var appId = modSource.Type.NodeWithKeyOrDefault("AppId");
+
+			if (appId == null)
+				return null;
+
+			if (Platform.CurrentPlatform != PlatformType.Windows)
+				return null;
+
+			// We need an extra check for the platform here to silence a warning when the registry is accessed
+			// TODO: Remove this once our platform checks use the same method
+			if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+				return null;
+
+			var prefixes = new[] { "HKEY_LOCAL_MACHINE\\Software\\", "HKEY_LOCAL_MACHINE\\SOFTWARE\\Wow6432Node\\" };
+
+			foreach (var prefix in prefixes)
+			{
+				if (Registry.GetValue($"{prefix}GOG.com\\Games\\{appId.Value.Value}", "path", null) is not string installDir)
+					continue;
+
+				if (InstallerUtils.IsValidSourcePath(installDir, modSource))
+					return installDir;
+			}
+
+			return null;
+		}
+
+		public Availability GetAvailability()
+		{
+			return Platform.CurrentPlatform != PlatformType.Windows ? Availability.DigitalInstall : Availability.Unavailable;
+		}
+	}
+}

OpenRA.Mods.Common/Installer/SourceResolvers/RegistryDirectoryFromFileSourceResolver.cs

@@ -0,0 +1,50 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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.IO;
+using System.Runtime.InteropServices;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class RegistryDirectoryFromFileSourceResolver : ISourceResolver
+	{
+		public string FindSourcePath(ModContent.ModSource source)
+		{
+			if (source.RegistryKey == null)
+				return null;
+
+			if (Platform.CurrentPlatform != PlatformType.Windows)
+				return null;
+
+			// We need an extra check for the platform here to silence a warning when the registry is accessed
+			// TODO: Remove this once our platform checks use the same method
+			if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+				return null;
+
+			foreach (var prefix in source.RegistryPrefixes)
+			{
+				if (Microsoft.Win32.Registry.GetValue(prefix + source.RegistryKey, source.RegistryValue, null) is not string path)
+					continue;
+
+				path = Path.GetDirectoryName(path);
+
+				return InstallerUtils.IsValidSourcePath(path, source) ? path : null;
+			}
+
+			return null;
+		}
+
+		public Availability GetAvailability()
+		{
+			return Platform.CurrentPlatform != PlatformType.Windows ? Availability.DigitalInstall : Availability.Unavailable;
+		}
+	}
+}

OpenRA.Mods.Common/Installer/SourceResolvers/RegistryDirectorySourceResolver.cs

@@ -0,0 +1,51 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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.IO;
+using System.Runtime.InteropServices;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class RegistryDirectorySourceResolver : ISourceResolver
+	{
+		public string FindSourcePath(ModContent.ModSource source)
+		{
+			if (source.RegistryKey == null)
+				return null;
+
+			if (Platform.CurrentPlatform != PlatformType.Windows)
+				return null;
+
+			// We need an extra check for the platform here to silence a warning when the registry is accessed
+			// TODO: Remove this once our platform checks use the same method
+			if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+				return null;
+
+			foreach (var prefix in source.RegistryPrefixes)
+			{
+				if (Microsoft.Win32.Registry.GetValue(prefix + source.RegistryKey, source.RegistryValue, null) is not string path)
+					continue;
+
+				// Resolve 8.3 format (DOS-style) paths to the full path.
+				path = Path.GetFullPath(path);
+
+				return InstallerUtils.IsValidSourcePath(path, source) ? path : null;
+			}
+
+			return null;
+		}
+
+		public Availability GetAvailability()
+		{
+			return Platform.CurrentPlatform != PlatformType.Windows ? Availability.DigitalInstall : Availability.Unavailable;
+		}
+	}
+}

OpenRA.Mods.Common/Installer/SourceResolvers/SteamSourceResolver.cs

@@ -0,0 +1,172 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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 System.Runtime.InteropServices;
+using System.Text.RegularExpressions;
+using Microsoft.Win32;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class SteamSourceResolver : ISourceResolver
+	{
+		public string FindSourcePath(ModContent.ModSource modSource)
+		{
+			var appId = modSource.Type.NodeWithKeyOrDefault("AppId");
+
+			if (appId == null)
+				return null;
+
+			foreach (var steamDirectory in SteamDirectory())
+			{
+				var manifestPath = Path.Combine(steamDirectory, "steamapps", $"appmanifest_{appId.Value.Value}.acf");
+
+				if (!File.Exists(manifestPath))
+					continue;
+
+				var data = ParseGameManifest(manifestPath);
+
+				if (!data.TryGetValue("StateFlags", out var stateFlags) || stateFlags != "4")
+					continue;
+
+				if (!data.TryGetValue("installdir", out var installDir))
+					continue;
+
+				if (installDir == null)
+					continue;
+
+				var path = Path.Combine(steamDirectory, "steamapps", "common", installDir);
+
+				if (InstallerUtils.IsValidSourcePath(path, modSource))
+					return path;
+			}
+
+			return null;
+		}
+
+		public Availability GetAvailability()
+		{
+			return Availability.DigitalInstall;
+		}
+
+		static IEnumerable<string> SteamDirectory()
+		{
+			var candidatePaths = new List<string>();
+
+			switch (Platform.CurrentPlatform)
+			{
+				case PlatformType.Windows:
+				{
+					// We need an extra check for the platform here to silence a warning when the registry is accessed
+					// TODO: Remove this once our platform checks use the same method
+					if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+						break;
+
+					var prefixes = new[] { "HKEY_LOCAL_MACHINE\\Software\\", "HKEY_LOCAL_MACHINE\\SOFTWARE\\Wow6432Node\\" };
+
+					foreach (var prefix in prefixes)
+					{
+						if (Registry.GetValue($"{prefix}Valve\\Steam", "InstallPath", null) is string path)
+							candidatePaths.Add(path);
+					}
+
+					break;
+				}
+
+				case PlatformType.OSX:
+					candidatePaths.Add(Path.Combine(
+						Environment.GetFolderPath(Environment.SpecialFolder.UserProfile),
+						"Library",
+						"Application Support",
+						"Steam"));
+
+					break;
+
+				case PlatformType.Linux:
+					// Direct distro install
+					candidatePaths.Add(Path.Combine(
+						Environment.GetFolderPath(Environment.SpecialFolder.UserProfile),
+						".steam",
+						"root"));
+
+					// Flatpak installed via Flathub
+					candidatePaths.Add(Path.Combine(
+						Environment.GetFolderPath(Environment.SpecialFolder.UserProfile),
+						".var",
+						"app",
+						"com.valvesoftware.Steam",
+						".steam",
+						"root"));
+
+					break;
+			}
+
+			foreach (var libraryPath in candidatePaths.Where(Directory.Exists))
+			{
+				yield return libraryPath;
+
+				var libraryFoldersPath = Path.Combine(libraryPath, "steamapps", "libraryfolders.vdf");
+
+				if (!File.Exists(libraryFoldersPath))
+					continue;
+
+				foreach (var e in ParseLibraryManifest(libraryFoldersPath).Where(e => e.Item1 == "path"))
+					yield return Unescape(e.Item2);
+			}
+		}
+
+		static string Unescape(string path)
+		{
+			return path.Replace(@"\\", @"\");
+		}
+
+		static Dictionary<string, string> ParseGameManifest(string path)
+		{
+			var regex = new Regex("^\\s*\"(?<key>[^\"]*)\"\\s*\"(?<value>[^\"]*)\"\\s*$");
+			var result = new Dictionary<string, string>();
+
+			using (var s = new FileStream(path, FileMode.Open))
+			{
+				foreach (var line in s.ReadAllLines())
+				{
+					var match = regex.Match(line);
+
+					if (match.Success)
+						result[match.Groups["key"].Value] = match.Groups["value"].Value;
+				}
+			}
+
+			return result;
+		}
+
+		static List<Tuple<string, string>> ParseLibraryManifest(string path)
+		{
+			var regex = new Regex("^\\s*\"(?<key>[^\"]*)\"\\s*\"(?<value>[^\"]*)\"\\s*$");
+			var result = new List<Tuple<string, string>>();
+
+			using (var s = new FileStream(path, FileMode.Open))
+			{
+				foreach (var line in s.ReadAllLines())
+				{
+					var match = regex.Match(line);
+
+					if (match.Success)
+						result.Add(new Tuple<string, string>(match.Groups["key"].Value, match.Groups["value"].Value));
+				}
+			}
+
+			return result;
+		}
+	}
+}