Crash Log when crashes, there can be only one.

AutoTrackR2/App.xaml.cs

@@ -1,6 +1,9 @@
 using System.Configuration;
 using System.Data;
 using System.Windows;
+using System.Threading;
+using System.IO;
+using System;
 
 namespace AutoTrackR2
 {
@@ -9,5 +12,101 @@ namespace AutoTrackR2
     /// </summary>
     public partial class App : System.Windows.Application
     {
+        private static Mutex _mutex = null;
+        private static bool _mutexOwned = false;
+        private static readonly string CrashLogPath = Path.Combine(
+            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
+            "AutoTrackR2",
+            "crash.log"
+        );
+
+        protected override void OnStartup(StartupEventArgs e)
+        {
+            // Ensure crash log directory exists
+            Directory.CreateDirectory(Path.GetDirectoryName(CrashLogPath));
+
+            // Set up unhandled exception handlers
+            AppDomain.CurrentDomain.UnhandledException += CurrentDomain_UnhandledException;
+            DispatcherUnhandledException += App_DispatcherUnhandledException;
+
+            const string appName = "AutoTrackR2";
+            bool createdNew;
+
+            _mutex = new Mutex(true, appName, out createdNew);
+            _mutexOwned = createdNew;
+
+            if (!createdNew)
+            {
+                // App is already running, silently exit
+                Current.Shutdown();
+                return;
+            }
+
+            base.OnStartup(e);
+        }
+
+        private void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
+        {
+            LogCrash(e.ExceptionObject as Exception);
+        }
+
+        private void App_DispatcherUnhandledException(object sender, System.Windows.Threading.DispatcherUnhandledExceptionEventArgs e)
+        {
+            LogCrash(e.Exception);
+            e.Handled = true; // Prevent the application from crashing
+        }
+
+        private void LogCrash(Exception? ex)
+        {
+            try
+            {
+                var timestamp = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss");
+                var logMessage = $"[{timestamp}] CRASH: {ex?.Message}\n" +
+                               $"Stack Trace:\n{ex?.StackTrace}\n" +
+                               $"Source: {ex?.Source}\n" +
+                               $"Target Site: {ex?.TargetSite}\n" +
+                               "----------------------------------------\n";
+
+                File.AppendAllText(CrashLogPath, logMessage);
+
+                // Show error message to user
+                MessageBox.Show(
+                    "AutoTrackR2 has encountered an error. A crash log has been created.\n" +
+                    $"Location: {CrashLogPath}",
+                    "AutoTrackR2 Error",
+                    MessageBoxButton.OK,
+                    MessageBoxImage.Error
+                );
+            }
+            catch (Exception logEx)
+            {
+                // If logging fails, at least show a basic error message
+                MessageBox.Show(
+                    "AutoTrackR2 has encountered an error and failed to create a crash log.\n" +
+                    $"Error: {ex?.Message}",
+                    "AutoTrackR2 Error",
+                    MessageBoxButton.OK,
+                    MessageBoxImage.Error
+                );
+            }
+        }
+
+        protected override void OnExit(ExitEventArgs e)
+        {
+            if (_mutex != null && _mutexOwned)
+            {
+                try
+                {
+                    _mutex.ReleaseMutex();
+                }
+                catch (Exception ex)
+                {
+                    // Log the mutex release error but don't throw
+                    LogCrash(ex);
+                }
+                _mutex.Dispose();
+            }
+            base.OnExit(e);
+        }
     }
 }

AutoTrackR2/ConfigPage.xaml.cs

@@ -398,10 +398,11 @@ public partial class ConfigPage : UserControl
             {
                 // Set headers
                 client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", apiKey);
-                client.DefaultRequestHeaders.UserAgent.ParseAdd("AutoTrackR");
+                client.DefaultRequestHeaders.UserAgent.ParseAdd("AutoTrackR2");
 
-                // Empty JSON body
-                var content = new StringContent("{}", Encoding.UTF8, "application/json");
+                // Create JSON body with version
+                var jsonBody = new { version = "2.10" };
+                var content = new StringContent(JsonSerializer.Serialize(jsonBody), Encoding.UTF8, "application/json");
 
                 // Send POST
                 var response = await client.PostAsync(modifiedUrl, content);