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Nitrox.Launcher/Models/Extensions/ScreenExtensions.cs

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+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Threading.Tasks;
+using CommunityToolkit.Mvvm.Messaging;
+using Nitrox.Launcher.Models.Design;
+using Nitrox.Launcher.Models.Utils;
+using Nitrox.Launcher.ViewModels.Abstract;
+
+namespace Nitrox.Launcher.Models.Extensions;
+
+public static class ScreenExtensions
+{
+    private static readonly List<RoutableViewModelBase> navigationStack = [];
+
+    /// <summary>
+    ///     Navigates to a view assigned to the given ViewModel.
+    /// </summary>
+    /// <param name="screen">The screen used to display the view.</param>
+    /// <param name="routableViewModel">ViewModel that should be shown.</param>
+    /// <typeparam name="TViewModel">Type of the ViewModel to show.</typeparam>
+    public static async Task ShowAsync<TViewModel>(this IRoutingScreen screen, TViewModel routableViewModel) where TViewModel : RoutableViewModelBase
+    {
+        if (screen == null)
+        {
+            return;
+        }
+        // When navigating away from a view in an async button command, busy states on buttons should also reset. Otherwise, when navigating back it would still show buttons being busy.
+        NitroxAttached.AsyncCommandButtonTagger.Clear();
+        if (screen.ActiveViewModel is RoutableViewModelBase routableViewModelBase)
+        {
+            navigationStack.RemoveAllFast(screen.ActiveViewModel, (item, param) => item.GetType() == param.GetType());
+            await routableViewModelBase.ViewContentUnloadAsync();
+            navigationStack.Add(routableViewModelBase);
+        }
+        Stopwatch sw = Stopwatch.StartNew();
+        Task contentLoadTask = routableViewModel.ViewContentLoadAsync();
+        if (screen.ActiveViewModel != null)
+        {
+            // Only show loading screen if page isn't loading super quickly.
+            await Task.Delay(50);
+            if (!contentLoadTask.IsCompleted)
+            {
+                screen.ActiveViewModel = AssetHelper.GetFullAssetPath("/Assets/Icons/loading.svg");
+                await Task.Delay((int)Math.Max(0, 500 - sw.Elapsed.TotalMilliseconds));
+            }
+        }
+        await contentLoadTask;
+        screen.ActiveViewModel = routableViewModel;
+    }
+
+    public static async Task<bool> BackAsync(this IRoutingScreen screen)
+    {
+        if (navigationStack.Count < 1)
+        {
+            return false;
+        }
+        RoutableViewModelBase backViewModel = navigationStack[^1];
+        navigationStack.Remove(backViewModel);
+        await ShowAsync(screen, backViewModel);
+        return true;
+    }
+
+    /// <summary>
+    ///     Tries to go back to the view assigned to the given ViewModel.
+    /// </summary>
+    /// <returns>
+    ///     True if ViewModel was found in the routing navigation stack. False when the ViewModel wasn't found and routing
+    ///     failed.
+    /// </returns>
+    public static async Task<bool> BackToAsync<T>(this IRoutingScreen screen) where T : RoutableViewModelBase
+    {
+        for (int i = navigationStack.Count - 1; i >= 0; i--)
+        {
+            if (navigationStack[i] is T target)
+            {
+                // Cleanup the stack up and including the back-target.
+                for (int j = i; j < navigationStack.Count; j++)
+                {
+                    navigationStack.RemoveAt(j);
+                }
+                await screen.ShowAsync(target);
+                return true;
+            }
+        }
+        return false;
+    }
+}