Better keyboard navigation

src/UniGetUI/Pages/SoftwarePages/AbstractPackagesPage.xaml

@@ -12,7 +12,9 @@
     mc:Ignorable="d"
     Name="ABSTRACT_PAGE"
     NavigationCacheMode="Required"
-    xmlns:animations="using:CommunityToolkit.WinUI.Animations" xmlns:pkgClasses="using:UniGetUI.PackageEngine.PackageClasses">
+    xmlns:animations="using:CommunityToolkit.WinUI.Animations" xmlns:pkgClasses="using:UniGetUI.PackageEngine.PackageClasses"
+    KeyDown="{x:Bind PackageList_KeyDown}">
+    <!-- PreviewKeyDown="{x:Bind PackageList_PreviewKeyDown}" -->
 
     <animations:Implicit.ShowAnimations>
         <animations:TranslationAnimation Duration="0:0:0.25" From="0,100,0" To="0"/>

src/UniGetUI/Pages/SoftwarePages/AbstractPackagesPage.xaml.cs

@@ -114,6 +114,10 @@ protected string NoMatches_SubtitleText
         }
         protected string FoundPackages_SubtitleText { get => NoMatches_SubtitleText; }
 
+        private string TypeQuery = "";
+        private int LastKeyDown;
+        private readonly int QUERY_SEPARATION_TIME = 1000; // 500ms between keypresses starts a new query
+
         protected AbstractPackagesPage(PackagesPageData data)
         {
             InitializeComponent();
@@ -482,6 +486,103 @@ protected async Task LoadPackages(ReloadReason reason)
             Loader_PackagesChanged(this, EventArgs.Empty);
         }
 
+        private void SelectAndScrollTo(int index)
+        {
+            PackageList.Select(index);
+            PackageList.ScrollView?.ScrollTo(0, Math.Max(0, (index - 3) * 39), new ScrollingScrollOptions
+            (
+                ScrollingAnimationMode.Disabled,
+                ScrollingSnapPointsMode.Ignore
+            ));
+        }
+
+        // To avoid the default arrow key behavior
+        // public void PackageList_PreviewKeyDown(object sender, KeyRoutedEventArgs e)
+        // {
+        //     int SelectedIndex = -1;
+        //     if (PackageList.SelectedItem is not null)
+        //     {
+        //         SelectedIndex = ((PackageWrapper)PackageList.SelectedItem).Index;
+        //     }
+
+        //     switch (e.Key)
+        //     {
+        //         case VirtualKey.Up:
+        //             e.Handled = true;
+        //             // no selection or first selected item
+        //             if (SelectedIndex <= 0)
+        //             {
+        //                 SelectAndScrollTo(FilteredPackages.Count - 1);
+        //             }
+        //             else
+        //             {
+        //                 SelectAndScrollTo(SelectedIndex - 1);
+        //             }
+        //             break;
+        //         case VirtualKey.Down:
+        //             e.Handled = true;
+        //             // no selection or last selected item
+        //             if (SelectedIndex < 0 || SelectedIndex == FilteredPackages.Count - 1)
+        //             {
+        //                 SelectAndScrollTo(0);
+        //             }
+        //             else
+        //             {
+        //                 SelectAndScrollTo(SelectedIndex + 1);
+        //             }
+        //             break;
+        //     }
+        // }
+
+        public void PackageList_KeyDown(object sender, KeyRoutedEventArgs e)
+        {
+            string key = ((char)e.Key).ToString().ToLower();
+            if ("abcdefghijklmnopqrsztuvwxyz1234567890".IndexOf(key) > -1)
+            {
+                if (Environment.TickCount - LastKeyDown > QUERY_SEPARATION_TIME)
+                {
+                    TypeQuery = key;
+                }
+                else
+                {
+                    TypeQuery += key;
+                }
+
+                int IdQueryIndex = -1;
+                int NameSimilarityIndex = -1;
+                int IdSimilarityIndex = -1;
+                bool SelectedPackage = false;
+                for (int i = 0; i < FilteredPackages.Count; i++)
+                {
+                    if (FilteredPackages[i].Package.Name.ToLower().StartsWith(TypeQuery))
+                    {
+                        SelectAndScrollTo(i);
+                        SelectedPackage = true;
+                        break;
+                    }
+                    // To avoid jumping back high up because an ID matched it (prevent typing "wi" focusing id:"WildfireGames.0AD" instead of name:"Windows")
+                    if (IdQueryIndex == -1 && FilteredPackages[i].Package.Id.ToLower().StartsWith(TypeQuery))
+                    {
+                        IdQueryIndex = i;
+                    }
+                    if (NameSimilarityIndex == -1 && FilteredPackages[i].Package.Name.ToLower().Contains(TypeQuery))
+                    {
+                        NameSimilarityIndex = i;
+                    }
+                    if (IdSimilarityIndex == -1 && FilteredPackages[i].Package.Id.ToLower().Contains(TypeQuery))
+                    {
+                        IdSimilarityIndex = i;
+                    }
+                }
+                int QueryIndex = IdQueryIndex > -1 ? IdQueryIndex : (NameSimilarityIndex > -1 ? NameSimilarityIndex : IdSimilarityIndex);
+                if (!SelectedPackage && QueryIndex > -1)
+                {
+                    SelectAndScrollTo(QueryIndex);
+                }
+            }
+            LastKeyDown = Environment.TickCount;
+        }
+
         /// <summary>
         /// Will filter the packages with the query on QueryBlock.Text and put the
         /// resulting packages on the ItemsView