Exit if the user has deleted the BepInEx/plugins/spt folder (!109)

Added as a check in the PrePatch, because while users delete `BepInEx/plugins/spt` often, it would be uncommon for them to also delete the prepatcher

No idea why there's a second commit in this PR, it doesn't actually change anything. Just Git Things™

Co-authored-by: Terkoiz <terkoiz@spt.dev>
Co-authored-by: DrakiaXYZ <565558+TheDgtl@users.noreply.github.com>
Reviewed-on: SPT-AKI/Modules#109
Co-authored-by: DrakiaXYZ <drakiaxyz@noreply.dev.sp-tarkov.com>
Co-committed-by: DrakiaXYZ <drakiaxyz@noreply.dev.sp-tarkov.com>

project/Aki.Core/Utils/ValidationUtil.cs

@@ -16,7 +16,7 @@ namespace Aki.Core.Utils
                 var v1 = Registry.LocalMachine.OpenSubKey(c0, false).GetValue("InstallLocation");
                 var v2 = (v1 != null) ? v1.ToString() : string.Empty;
                 var v3 = new DirectoryInfo(v2);
-                
+
                 var v4 = new FileSystemInfo[]
                 {
                     v3,
@@ -55,4 +55,4 @@ namespace Aki.Core.Utils
             return File.Exists(a) ? new FileInfo(a) : null;
         }
     }
-}
+}

project/Aki.PrePatch/AkiBotsPrePatcher.cs

@@ -1,4 +1,8 @@
+using System;
 using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using BepInEx.Logging;
 using Mono.Cecil;
 
 namespace Aki.PrePatch
@@ -10,8 +14,22 @@ namespace Aki.PrePatch
         public static int sptUsecValue = 49;
         public static int sptBearValue = 50;
 
+        private static string _sptPluginFolder = "plugins/spt";
+
         public static void Patch(ref AssemblyDefinition assembly)
         {
+            // Make sure the user hasn't deleted the SPT plugins folder
+            string assemblyFolder = Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location);
+            string sptPluginPath = Path.GetFullPath(Path.Combine(assemblyFolder, "..", _sptPluginFolder));
+            if (!ValidateSpt(sptPluginPath))
+            {
+                string message = $"'{sptPluginPath}' or required plugin files not found.\n\n" +
+                    "Please re-install SPT. Exiting.";
+                MessageBoxHelper.Show(message, "[SPT-AKI] Missing Core Files", MessageBoxHelper.MessageBoxType.OK);
+                Environment.Exit(0);
+                return;
+            }
+
             var botEnums = assembly.MainModule.GetType("EFT.WildSpawnType");
 
             var sptUsec = new FieldDefinition("sptUsec",
@@ -27,5 +45,31 @@ namespace Aki.PrePatch
             botEnums.Fields.Add(sptUsec);
             botEnums.Fields.Add(sptBear);
         }
+
+        private static bool ValidateSpt(string sptPluginPath)
+        {
+            ManualLogSource logger = Logger.CreateLogSource(nameof(AkiBotsPrePatcher));
+
+            // Validate that the SPT plugin path exists
+            if (!Directory.Exists(sptPluginPath))
+            {
+                logger.LogError($"'{sptPluginPath}' directory not found");
+                return false;
+            }
+
+            // Validate that the folder exists, and contains our plugins
+            string[] sptPlugins = new string[] { "aki-core.dll", "aki-custom.dll", "aki-singleplayer.dll" };
+            string[] foundPlugins = Directory.GetFiles(sptPluginPath).Select(x => Path.GetFileName(x)).ToArray();
+
+            foreach (string plugin in sptPlugins)
+            {
+                if (!foundPlugins.Contains(plugin))
+                {
+                    return false;
+                }
+            }
+
+            return true;
+        }
     }
 }

project/Aki.PrePatch/MessageBoxHelper.cs

@@ -0,0 +1,56 @@
+using System;
+using System.Runtime.InteropServices;
+
+namespace Aki.PrePatch
+{
+    internal class MessageBoxHelper
+    {
+        public enum MessageBoxType : uint
+        {
+            ABORTRETRYIGNORE = (uint)(0x00000002L | 0x00000010L),
+            CANCELTRYCONTINUE = (uint)(0x00000006L | 0x00000030L),
+            HELP = (uint)(0x00004000L | 0x00000040L),
+            OK = (uint)(0x00000000L | 0x00000040L),
+            OKCANCEL = (uint)(0x00000001L | 0x00000040L),
+            RETRYCANCEL = (uint)0x00000005L,
+            YESNO = (uint)(0x00000004L | 0x00000040L),
+            YESNOCANCEL = (uint)(0x00000003L | 0x00000040L),
+            DEFAULT = (uint)(0x00000000L | 0x00000010L)
+        }
+
+        public enum MessageBoxResult
+        {
+            ERROR = -1,
+            OK = 1,
+            CANCEL = 2,
+            ABORT = 3,
+            RETRY = 4,
+            IGNORE = 5,
+            YES = 6,
+            NO = 7,
+            TRY_AGAIN = 10
+        }
+
+        [DllImport("user32.dll")]
+        private static extern IntPtr GetActiveWindow();
+        [DllImport("user32.dll", SetLastError = true)]
+        static extern int MessageBox(IntPtr hwnd, String lpText, String lpCaption, uint uType);
+
+        public static IntPtr GetWindowHandle()
+        {
+            return GetActiveWindow();
+        }
+
+        public static MessageBoxResult Show(string text, string caption, MessageBoxType type = MessageBoxType.DEFAULT)
+        {
+            try
+            {
+                return (MessageBoxResult)MessageBox(GetWindowHandle(), text, caption, (uint)type); ;
+            }
+            catch (Exception)
+            {
+                return MessageBoxResult.ERROR;
+            }
+        }
+    }
+}