Detects when the user removes the ModuleManager/L's and/or `ModuleM…

…anagerWatchDog`'s directory(ies), and shut everything down accordingly.

For #10

Source/ModuleManagerWatchDog/ModuleManagerWatchDog.csproj

@@ -57,6 +57,7 @@
     <Compile Include="GUI\WarningAlertbox.cs" />
     <Compile Include="InstallChecker.cs" />
     <Compile Include="Util\Toolbox.cs" />
+    <Compile Include="Util\SelfCleaning.cs" />
   </ItemGroup>
   <ItemGroup>
     <None Include="Properties\Version.tt">

Source/ModuleManagerWatchDog/Startup.cs

@@ -24,6 +24,30 @@ internal class Startup : MonoBehaviour
 		private void Start()
 		{
 			Log.force("Version {0}", ModuleManagerWatchDog.Version.Text);
+			{
+				bool safeToKillMyself = true;
+				// Check if ModuleManager /L should be uninstalled
+				if (SelfCleaning.CheckUninstalled("ModuleManager", "ModuleManager.dll"))
+				{
+					Log.warn("ModuleManager /L's directory was removed. ModuleManagerWatchDog is removing ModuleManager /L from the Loading System, but some `*.delete-me` files may be left in your `GameData` until the next boot. Nothing bad will happen by leaving them there, however.");
+					SelfCleaning.KillThis("ModuleManager.dll");
+					safeToKillMyself = false;
+				}
+
+				// Check if ModuleManagerWatchDog should be uninstalled
+				if (SelfCleaning.CheckUninstalled("ModuleManagerWatchDog", "666_ModuleManagerWatchDog.dll"))
+				{
+					if (safeToKillMyself)
+					{
+						Log.warn("ModuleManagerWatchDog's directory was removed. The bootstrap is removing itself from the Loading System, but you may need to delete manually some `*.delete-me` files in your `GameData`. Nothing bad will happen by leaving them there, however.");
+						SelfCleaning.KillThis("666_ModuleManagerWatchDog.dll");
+					}
+					else
+						Log.warn("ModuleManagerWatchDog's directory was removed, but some housekeeping is still in progress. It will remove itself in the next boot.");
+					// We are dead. No further actions should be allowed.
+					return;
+				}
+			}
 			{
 				InstallChecker ic = new InstallChecker();
 				ic.Execute();

Source/ModuleManagerWatchDog/Util/Log.cs

@@ -30,6 +30,11 @@ internal static void info(string msg, params object[] @params)
 			UnityEngine.Debug.LogFormat("[ModuleManagerWatchDog] INFO: " + msg, @params);
 		}
 
+		internal static void warn(string msg, params object[] @params)
+		{
+			UnityEngine.Debug.LogWarningFormat("[ModuleManagerWatchDog] WARNING: " + msg, @params);
+		}
+
 		internal static void detail(string msg, params object[] @params)
 		{
 			UnityEngine.Debug.LogFormat("[ModuleManagerWatchDog] DETAIL: " + msg, @params);

Source/ModuleManagerWatchDog/Util/SelfCleaning.cs

@@ -0,0 +1,65 @@
+/*
+	This file is part of Module Manager Watch Dog
+		©2020-2024 Lisias T : http://lisias.net <[email protected]>
+
+	Module Manager Watch Dog is licensed as follows:
+		* SKL 1.0 : https://ksp.lisias.net/SKL-1_0.txt
+
+	Module Manager Watchdog is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+	You should have received a copy of the SKL Standard License 1.0
+	along with Module Manager Watch Dog. If not, see
+	<https://ksp.lisias.net/SKL-1_0.txt>.
+
+*/
+using System;
+using SIO = System.IO;
+
+namespace WatchDog.ModuleManager
+{
+	public static class SelfCleaning
+	{
+		private const string DELETEME = ".delete-me";
+		private static readonly string GAMEDATA = SanityLib.GetPathFor("GameData");
+
+		internal static bool CheckUninstalled(string directory, string dllName)
+		{
+			string dirpathname = SIO.Path.Combine(GAMEDATA, directory);
+			string dllpathname = SIO.Path.Combine(GAMEDATA, dllName);
+			return SIO.File.Exists(dllpathname) && !SIO.Directory.Exists(dirpathname);
+		}
+
+		internal static bool KillThis(string dllName)
+		{
+			string pathname = SIO.Path.Combine(GAMEDATA, dllName);
+			bool r = SIO.File.Exists(pathname);
+			if (r) Delete(pathname);
+			else
+			{
+				string tempname = pathname + DELETEME;
+				if (SIO.File.Exists(tempname)) SIO.File.Delete(tempname);
+			}
+			return r;
+		}
+
+		private static void Delete(string filename)
+		{
+			Log.dbg("Deleting {0}", filename);
+			if (SIO.File.Exists(filename)) try
+			{
+				SIO.File.Delete(filename);
+			}
+			catch (Exception e) when (e is System.UnauthorizedAccessException || e is System.Security.SecurityException)
+			{
+				// Oukey, we are in Windows and it locks the DLL file once it's loaded.
+				// But we can rename it, and delete it later.
+				string tempname = filename + DELETEME;
+				if (SIO.File.Exists(tempname)) SIO.File.Delete(tempname);
+				SIO.File.Move(filename, tempname);
+			}
+		}
+
+	}
+}