From c646036b7384fe5fad063a3919723bd3e2fd27f3 Mon Sep 17 00:00:00 2001
From: TheXamlGuy <dan_clark@outlook.com>
Date: Tue, 25 Jun 2024 23:08:45 +0100
Subject: [PATCH] More UI improvements

---
 Toolkit.Avalonia/FrameHandler.cs              |  5 +-
 .../PersonPicture/PersonPicture.axaml         | 17 +++--
 .../PersonPicture/PersonPicture.cs            | 10 ++-
 .../PersonPictureColourGenerator.cs           | 75 +++++++++++++++++++
 4 files changed, 96 insertions(+), 11 deletions(-)
 create mode 100644 Toolkit.UI.Controls.Avalonia/PersonPicture/PersonPictureColourGenerator.cs

diff --git a/Toolkit.Avalonia/FrameHandler.cs b/Toolkit.Avalonia/FrameHandler.cs
index 3dbcdd8..f855733 100644
--- a/Toolkit.Avalonia/FrameHandler.cs
+++ b/Toolkit.Avalonia/FrameHandler.cs
@@ -168,12 +168,13 @@ public class FrameHandler :
                         }
                     }
                 }
-
-                frame.NavigateFromObject(control, navigationOptions);
                 foreach (Action postAction in postNavigateActions)
                 {
                     postAction.Invoke();
                 }
+
+                frame.NavigateFromObject(control, navigationOptions);
+
             }
         }
 
diff --git a/Toolkit.UI.Controls.Avalonia/PersonPicture/PersonPicture.axaml b/Toolkit.UI.Controls.Avalonia/PersonPicture/PersonPicture.axaml
index a0741ce..f1f81b5 100644
--- a/Toolkit.UI.Controls.Avalonia/PersonPicture/PersonPicture.axaml
+++ b/Toolkit.UI.Controls.Avalonia/PersonPicture/PersonPicture.axaml
@@ -4,19 +4,19 @@
     xmlns:controls="using:Toolkit.UI.Controls.Avalonia">
     <ResourceDictionary.ThemeDictionaries>
         <ResourceDictionary x:Key="Light">
-            <StaticResource x:Key="PersonPictureForegroundThemeBrush" ResourceKey="TextFillColorPrimaryBrush" />
+            <StaticResource x:Key="PersonPictureForegroundThemeBrush" ResourceKey="TextOnAccentFillColorSelectedText" />
             <StaticResource x:Key="PersonPictureEllipseBadgeForegroundThemeBrush" ResourceKey="TextOnAccentFillColorPrimaryBrush" />
             <StaticResource x:Key="PersonPictureEllipseBadgeFillThemeBrush" ResourceKey="AccentFillColorDefaultBrush" />
             <StaticResource x:Key="PersonPictureEllipseBadgeStrokeThemeBrush" ResourceKey="ControlFillColorTransparentBrush" />
-            <StaticResource x:Key="PersonPictureEllipseFillThemeBrush" ResourceKey="ControlAltFillColorQuarternaryBrush" />
+            <StaticResource x:Key="PersonPictureEllipseFillThemeBrush" ResourceKey="ControlFillColorDefaultBrush" />
             <StaticResource x:Key="PersonPictureEllipseFillStrokeBrush" ResourceKey="CardStrokeColorDefaultBrush" />
         </ResourceDictionary>
         <ResourceDictionary x:Key="Dark">
-            <StaticResource x:Key="PersonPictureForegroundThemeBrush" ResourceKey="TextFillColorPrimaryBrush" />
+            <StaticResource x:Key="PersonPictureForegroundThemeBrush" ResourceKey="TextOnAccentFillColorSelectedText" />
             <StaticResource x:Key="PersonPictureEllipseBadgeForegroundThemeBrush" ResourceKey="TextOnAccentFillColorPrimaryBrush" />
             <StaticResource x:Key="PersonPictureEllipseBadgeFillThemeBrush" ResourceKey="AccentFillColorDefaultBrush" />
             <StaticResource x:Key="PersonPictureEllipseBadgeStrokeThemeBrush" ResourceKey="ControlFillColorTransparentBrush" />
-            <StaticResource x:Key="PersonPictureEllipseFillThemeBrush" ResourceKey="ControlAltFillColorQuarternaryBrush" />
+            <StaticResource x:Key="PersonPictureEllipseFillThemeBrush" ResourceKey="ControlFillColorDefaultBrush" />
             <StaticResource x:Key="PersonPictureEllipseFillStrokeBrush" ResourceKey="CardStrokeColorDefaultBrush" />
         </ResourceDictionary>
     </ResourceDictionary.ThemeDictionaries>
@@ -27,18 +27,19 @@
     <Thickness x:Key="PersonPictureBadgeGridMargin">0,-4,-4,0</Thickness>
     <ControlTheme x:Key="{x:Type controls:PersonPicture}" TargetType="controls:PersonPicture">
         <Setter Property="Foreground" Value="{DynamicResource PersonPictureForegroundThemeBrush}" />
+        <Setter Property="FontFamily" Value="{DynamicResource ContentControlThemeFontFamily}" />
+        <Setter Property="Background" Value="{DynamicResource PersonPictureEllipseFillThemeBrush}" />
+        <Setter Property="FontWeight" Value="600" />
+        <Setter Property="IsTabStop" Value="False" />
         <Setter Property="Width" Value="100" />
         <Setter Property="Height" Value="100" />
-        <Setter Property="FontFamily" Value="{DynamicResource ContentControlThemeFontFamily}" />
-        <Setter Property="FontWeight" Value="350" />
-        <Setter Property="IsTabStop" Value="False" />
         <Setter Property="Template">
             <ControlTemplate>
                 <Grid x:Name="RootGrid">
                     <Ellipse
                         Width="{TemplateBinding Width}"
                         Height="{TemplateBinding Height}"
-                        Fill="{DynamicResource PersonPictureEllipseFillThemeBrush}"
+                        Fill="{TemplateBinding Background}"
                         Stroke="{DynamicResource PersonPictureEllipseFillStrokeBrush}"
                         StrokeThickness="{DynamicResource PersonPictureEllipseStrokeThickness}" />
                     <TextBlock
diff --git a/Toolkit.UI.Controls.Avalonia/PersonPicture/PersonPicture.cs b/Toolkit.UI.Controls.Avalonia/PersonPicture/PersonPicture.cs
index 74d9cfb..70a998b 100644
--- a/Toolkit.UI.Controls.Avalonia/PersonPicture/PersonPicture.cs
+++ b/Toolkit.UI.Controls.Avalonia/PersonPicture/PersonPicture.cs
@@ -7,6 +7,7 @@ using Avalonia.Media.Imaging;
 
 namespace Toolkit.UI.Controls.Avalonia;
 
+
 public class PersonPicture : TemplatedControl
 {
     public static readonly StyledProperty<string> BadgeGlyphProperty =
@@ -36,11 +37,12 @@ public class PersonPicture : TemplatedControl
     private static readonly StyledProperty<PersonPictureTemplateSettings> TemplateSettingsProperty =
         AvaloniaProperty.Register<PersonPicture, PersonPictureTemplateSettings>(nameof(TemplateSettings));
 
+    private readonly ImageBrush? badgeImageBrush;
     private FontIcon? badgeGlyphIcon;
-    private ImageBrush? badgeImageBrush;
     private TextBlock? badgeNumberTextBlock;
     private Ellipse? badgingBackgroundEllipse;
     private Ellipse? badgingEllipse;
+    private PersonPictureColourGenerator colourGenerator = new(hue: 210, saturation: 0.8f, lightness: 0.6f);
     private string? displayNameInitials;
     private TextBlock? initialsTextBlock;
 
@@ -335,6 +337,12 @@ public class PersonPicture : TemplatedControl
         PersonPictureTemplateSettings templateSettings = TemplateSettings;
         templateSettings.ActualInitials = initials;
 
+        if (DisplayName is { Length: > 0 })
+        {
+            Color rgb = colourGenerator.Create(DisplayName);
+            SetValue(BackgroundProperty, new SolidColorBrush(Color.FromArgb(rgb.A, rgb.R, rgb.G, rgb.B)));
+        }
+
         if (imageSource is not null)
         {
             ImageBrush? imageBrush = templateSettings.ActualImageBrush;
diff --git a/Toolkit.UI.Controls.Avalonia/PersonPicture/PersonPictureColourGenerator.cs b/Toolkit.UI.Controls.Avalonia/PersonPicture/PersonPictureColourGenerator.cs
new file mode 100644
index 0000000..0eca004
--- /dev/null
+++ b/Toolkit.UI.Controls.Avalonia/PersonPicture/PersonPictureColourGenerator.cs
@@ -0,0 +1,75 @@
+using Avalonia.Media;
+using System.Security.Cryptography;
+using System.Text;
+
+namespace Toolkit.UI.Controls.Avalonia;
+
+public class PersonPictureColourGenerator
+{
+    private readonly float hue;
+    private readonly float saturation;
+    private readonly float lightness;
+    private const float minLightness = 0.2f;
+    private const float maxLightness = 0.8f;
+
+    public PersonPictureColourGenerator(float hue = 210, 
+        float saturation = 0.8f,
+        float lightness = 0.6f)
+    {
+        this.hue = hue;
+        this.saturation = saturation;
+        this.lightness = lightness;
+    }
+
+    public Color Create(string input)
+    {
+        byte[] hashBytes = GetHash(input);
+
+        float h = (hashBytes[0] + hue) % 360;
+        float s = (hashBytes[1] / 255.0f) * saturation;
+        float l = EnsureNonExtremeLightness((hashBytes[2] / 255.0f) * lightness);
+
+        (byte r, byte g, byte b) = HslToRgb(h, s, l);
+
+        return Color.FromRgb(r, g, b);
+    }
+
+    private byte[] GetHash(string input) => 
+        SHA256.HashData(Encoding.UTF8.GetBytes(input));
+
+    private float EnsureNonExtremeLightness(float calculatedLightness) => 
+        calculatedLightness < minLightness ? minLightness : calculatedLightness > maxLightness ?
+        maxLightness : calculatedLightness;
+
+    private (byte r, byte g, byte b) HslToRgb(float h, float s, float l)
+    {
+        h /= 360;
+        float r, g, b;
+
+        if (s == 0)
+        {
+            r = g = b = l;
+        }
+        else
+        {
+            float q = l < 0.5f ? l * (1 + s) : l + s - l * s;
+            float p = 2 * l - q;
+
+            r = HueToRgb(p, q, h + 1.0f / 3.0f);
+            g = HueToRgb(p, q, h);
+            b = HueToRgb(p, q, h - 1.0f / 3.0f);
+        }
+
+        return ((byte)(r * 255), (byte)(g * 255), (byte)(b * 255));
+    }
+
+    private float HueToRgb(float p, float q, float t)
+    {
+        if (t < 0) t += 1;
+        if (t > 1) t -= 1;
+        if (t < 1.0f / 6.0f) return p + (q - p) * 6 * t;
+        if (t < 1.0f / 2.0f) return q;
+        if (t < 2.0f / 3.0f) return p + (q - p) * (2.0f / 3.0f - t) * 6;
+        return p;
+    }
+}