Offer option to automatically remove unwanted plugins on launch

This commit allows option to automatically delete unwanted VR plugins.
All user needs to do is to click 'yes'.

Additionally game is checked before launch for being UE title and
warning is issued if it's not.

This requires `--attach=` parameter to be full path to game executable.
If only process name is passed old behavior is used instead.

UEVR/MainWindow.xaml.cs

@@ -31,6 +31,7 @@
 using static UEVR.SharedMemory;
 using System.Threading.Channels;
 using System.Security.Principal;
+using Path = System.IO.Path;
 
 namespace UEVR {
     class GameSettingEntry : INotifyPropertyChanged {
@@ -172,6 +173,7 @@ public partial class MainWindow : Window {
 
         private ExecutableFilter m_executableFilter = new ExecutableFilter();
         private string? m_commandLineAttachExe = null;
+        private string? m_commandLineAttachExePath = null;
         private string? m_commandLineLaunchExe = null;
         private string? m_commandLineLaunchArgs = null;
         private int m_commandLineDelayInjection = 0;
@@ -190,6 +192,11 @@ public MainWindow() {
             foreach (string arg in args) {
                 if (arg.StartsWith("--attach=")) {
                     m_commandLineAttachExe = arg.Split('=')[1];
+
+                    if(m_commandLineAttachExe.EndsWith(".exe")) {
+                        m_commandLineAttachExePath = Path.GetDirectoryName(m_commandLineAttachExe);
+                        m_commandLineAttachExe = Path.GetFileNameWithoutExtension(m_commandLineAttachExe);
+                    }
                     continue;
                 }
                 if (arg.StartsWith("--launch=")) {
@@ -286,6 +293,39 @@ private void Update_InjectStatus() {
             TimeSpan oneSecond = TimeSpan.FromSeconds(1);
 
             if (m_commandLineLaunchExe != null && !m_launchExeDone) {
+                if(m_commandLineAttachExePath != null && m_commandLineAttachExe != null) {
+                    if(!IsUnrealEngineGame(m_commandLineAttachExePath, m_commandLineAttachExe)) {
+                        var result = MessageBox.Show(m_lastSelectedProcessName + " does not appear to be an Unreal Engine title.\n" +
+                                                    "Do you want to proceed?",
+                                                    "Non UE game",
+                                                    MessageBoxButton.YesNo, MessageBoxImage.Warning);
+                        switch (result) {
+                            case MessageBoxResult.Yes:
+                                break;
+                            case MessageBoxResult.No:
+                                Application.Current.Dispatcher.Invoke(new Action(() => { Application.Current.Shutdown(1); }));
+                                break;
+                        };
+                    }
+
+                    var pluginsDir = AreVRPluginsPresent(m_commandLineAttachExePath);
+                    if(pluginsDir != null) {
+                        var result = MessageBox.Show("VR plugins have been detected in game directory.\n" +
+                                                     "Do you want to automatically remove them?\n" +
+                                                     "NOTE: for a handful of games deleting VR plugins will lead to game crashes",
+                                                     "VR Plugins detected",
+                                                     MessageBoxButton.YesNo, MessageBoxImage.Question);
+
+                        switch (result) {
+                            case MessageBoxResult.Yes:
+                                RemoveVRPlugins(pluginsDir);
+                                break;
+                            case MessageBoxResult.No:
+                                break;
+                        };
+                    }
+                }
+
                 try {
                     Process.Start(new ProcessStartInfo {
                         FileName = m_commandLineLaunchExe,
@@ -689,6 +729,22 @@ private void MainWindow_Closing(object sender, System.ComponentModel.CancelEvent
             return null;
         }
 
+        private void RemoveVRPlugins(string? pluginsPath) {
+            if(pluginsPath == null) return;
+
+            foreach (string discouragedPlugin in m_discouragedPlugins) {
+                string pluginPath = pluginsPath + "\\" + discouragedPlugin;
+
+                if (Directory.Exists(pluginPath)) {
+                    try {
+                        Directory.Delete(pluginPath, true);
+                    } catch (Exception) {
+                        MessageBox.Show("Failed to delete:" + pluginPath);
+                    }
+                }
+            }
+        }
+
         private bool IsUnrealEngineGame(string gameDirectory, string targetName) {
             try {
                 if (targetName.ToLower().EndsWith("-win64-shipping")) {