Added GoG and Steam SourceResolver.

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

@@ -0,0 +1,52 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2022 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.Runtime.InteropServices;
+using Microsoft.Win32;
+
+namespace OpenRA.Mods.Common.Installer
+{
+	public class GogSourceResolver : ISourceResolver
+	{
+		public string FindSourcePath(ModContent.ModSource modSource)
+		{
+			modSource.Type.ToDictionary().TryGetValue("AppId", out var 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)
+			{
+				var installDir = Registry.GetValue($"{prefix}GOG.com\\Games\\{appId.Value}", "path", null) as string;
+
+				if (installDir != null)
+					return installDir;
+			}
+
+			return null;
+		}
+
+		public Availability GetAvailability()
+		{
+			return Platform.CurrentPlatform != PlatformType.Windows ? Availability.DigitalInstall : Availability.Unavailable;
+		}
+	}
+}

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

@@ -0,0 +1,148 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2022 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 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)
+		{
+			modSource.Type.ToDictionary().TryGetValue("AppId", out var appId);
+
+			if (appId == null)
+				return null;
+
+			foreach (var steamDirectory in SteamDirectory())
+			{
+				var manifestPath = Path.Combine(steamDirectory, "steamapps", $"appmanifest_{appId.Value}.acf");
+
+				if (!File.Exists(manifestPath))
+					continue;
+
+				var data = ParseGameManifest(manifestPath);
+
+				if (!data.TryGetValue("StateFlags", out var stateFlags) || stateFlags != "4")
+					continue;
+
+				if (!data.TryGetValue("installdir", out var installDir))
+					continue;
+
+				if (installDir != null)
+					return Path.Combine(steamDirectory, "steamapps", "common", installDir);
+			}
+
+			return null;
+		}
+
+		public Availability GetAvailability()
+		{
+			return Availability.DigitalInstall;
+		}
+
+		static IEnumerable<string> SteamDirectory()
+		{
+			var candidatePaths = new List<string>();
+
+			switch (Platform.CurrentPlatform)
+			{
+				case PlatformType.Windows:
+				{
+					// We need an extra check for the platform here to silence a warning when the registry is accessed
+					// TODO: Remove this once our platform checks use the same method
+					if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+						break;
+
+					var prefixes = new[] { "HKEY_LOCAL_MACHINE\\Software\\", "HKEY_LOCAL_MACHINE\\SOFTWARE\\Wow6432Node\\" };
+
+					foreach (var prefix in prefixes)
+					{
+						if (Registry.GetValue($"{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:
+					candidatePaths.Add(Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.UserProfile), ".steam", "root"));
+
+					break;
+
+				default:
+					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 e.Item2;
+			}
+		}
+
+		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;
+		}
+	}
+}