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Nitrox.Launcher/ViewModels/Abstract/ViewModelBase.cs

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+using System;
+using System.Diagnostics;
+using Avalonia.Controls;
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Messaging;
+using Nitrox.Launcher.Models;
+
+namespace Nitrox.Launcher.ViewModels.Abstract;
+
+public abstract class ViewModelBase : ObservableValidator, IMessageReceiver
+{
+    protected Window MainWindow => AppViewLocator.MainWindow;
+
+    protected ViewModelBase()
+    {
+        ThrowIfViewModelCtorWasEmptyWhileNonEmptyExists();
+    }
+
+    public virtual void Dispose() => WeakReferenceMessenger.Default.UnregisterAll(this);
+
+    /// <summary>
+    ///     This will check that DI did not call the empty ViewModel constructor if dependencies for another constructor aren't met.
+    /// </summary>
+    [Conditional("DEBUG")]
+    private static void ThrowIfViewModelCtorWasEmptyWhileNonEmptyExists()
+    {
+        if (Design.IsDesignMode)
+        {
+            return;
+        }
+        foreach (StackFrame stackFrame in new StackTrace(2, false).GetFrames())
+        {
+            if (stackFrame.GetMethod() is not { IsConstructor: true } method)
+            {
+                continue;
+            }
+            if (method.DeclaringType is not { IsAbstract: false } declaringType)
+            {
+                continue;
+            }
+            if (method.GetParameters().Length > 0 || declaringType.GetConstructors().Length == 1)
+            {
+                break;
+            }
+            throw new Exception($"Empty ViewModel constructor of '{declaringType.Name}' should only be used in design mode! Check that the DI-container has all the dependencies to call a different constructor.");
+        }
+    }
+}