ui: draw window border on windows

Author: mjcheetham

src/shared/Core/UI/Assets/Base.axaml

@@ -6,12 +6,14 @@
             <Color x:Key="WindowBackgroundColor">#F6F6F6</Color>
             <SolidColorBrush x:Key="WindowBackgroundBrush" Color="{StaticResource WindowBackgroundColor}"/>
             <SolidColorBrush x:Key="DialogWindowCloseButtonBrush" Color="Black"/>
+            <SolidColorBrush x:Key="DialogWindowBorderBrush" Color="#CCCEDB"/>
         </ResourceDictionary>
 
         <ResourceDictionary x:Key="Dark">
             <Color x:Key="WindowBackgroundColor">#282828</Color>
             <SolidColorBrush x:Key="WindowBackgroundBrush" Color="{StaticResource WindowBackgroundColor}"/>
             <SolidColorBrush x:Key="DialogWindowCloseButtonBrush" Color="White"/>
+            <SolidColorBrush x:Key="DialogWindowBorderBrush" Color="#474747"/>
         </ResourceDictionary>
 
     </ResourceDictionary.ThemeDictionaries>

src/shared/Core/UI/Controls/DialogWindow.axaml

@@ -18,7 +18,8 @@
     <Design.DataContext>
         <vm:WindowViewModel/>
     </Design.DataContext>
-    <Border>
+    <Border BorderBrush="{DynamicResource DialogWindowBorderBrush}"
+            BorderThickness="{Binding ShowCustomWindowBorder, Converter={x:Static converters:BoolConvertersEx.ToThickness}}">
         <DockPanel>
             <DockPanel DockPanel.Dock="Top" HorizontalAlignment="Stretch" Margin="0"
                        IsVisible="{Binding ShowCustomChrome}">

src/shared/Core/UI/Converters/BoolConvertersEx.cs

@@ -1,14 +1,42 @@
+using System;
+using System.Globalization;
 using System.Linq;
+using Avalonia;
 using Avalonia.Data.Converters;
 
 namespace GitCredentialManager.UI.Converters
 {
     public static class BoolConvertersEx
     {
+        public static readonly IValueConverter ToThickness = new BoolToThicknessConverter(); 
+
         public static readonly IMultiValueConverter Or =
             new FuncMultiValueConverter<bool,bool>(x => x.Aggregate(false, (a, b) => a || b));
 
         public static readonly IMultiValueConverter And =
             new FuncMultiValueConverter<bool,bool>(x => x.Aggregate(true, (a, b) => a && b));
+
+        private class BoolToThicknessConverter : IValueConverter
+        {
+            public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+            {
+                if (value is not bool b)
+                {
+                    return null;
+                }
+
+                if (parameter is int i)
+                {
+                    return b ? new Thickness(i) : new Thickness(0);
+                }
+
+                return b ? new Thickness(1) : new Thickness(0);
+            }
+
+            public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+            {
+                return null;
+            }
+        }
     }
 }

src/shared/Core/UI/ViewModels/WindowViewModel.cs

@@ -35,13 +35,20 @@ public bool ShowCustomChrome
             get => ShowCustomChromeOverride || (ExtendClientArea && !PlatformUtils.IsMacOS());
         }
 
+        public bool ShowCustomWindowBorder
+        {
+            // Draw the window border explicitly on Windows
+            get => ShowCustomChrome && PlatformUtils.IsWindows();
+        }
+
         public bool ShowCustomChromeOverride
         {
             get => _showCustomChromeOverride;
             set
             {
                 SetAndRaisePropertyChanged(ref _showCustomChromeOverride, value);
                 RaisePropertyChanged(nameof(ShowCustomChrome));
+                RaisePropertyChanged(nameof(ShowCustomWindowBorder));
             }
         }
 
@@ -52,6 +59,7 @@ public bool ExtendClientArea
             {
                 SetAndRaisePropertyChanged(ref _extendClientArea, value);
                 RaisePropertyChanged(nameof(ShowCustomChrome));
+                RaisePropertyChanged(nameof(ShowCustomWindowBorder));
             }
         }