Refactor PieControl into focused visual, animation, and selection helpers

RadialActions.Tests/PieSelectionControllerTests.cs

@@ -0,0 +1,88 @@
+using System.Windows.Input;
+
+namespace RadialActions.Tests;
+
+public class PieSelectionControllerTests
+{
+    private static readonly PieSelectionController.Item[] DirectionalItems =
+    [
+        new(0, -60),
+        new(1, 20),
+        new(2, 100),
+        new(3, 170),
+    ];
+
+    [Theory]
+    [InlineData(Key.Up, 0)]
+    [InlineData(Key.Right, 1)]
+    [InlineData(Key.Down, 2)]
+    [InlineData(Key.Left, 3)]
+    public void HandleArrowKey_FirstSelectionChoosesClosestSlice(Key key, int expectedIndex)
+    {
+        var controller = new PieSelectionController();
+
+        controller.HandleArrowKey(key, DirectionalItems);
+
+        Assert.Equal(expectedIndex, controller.SelectedIndex);
+    }
+
+    [Theory]
+    [InlineData(Key.Left)]
+    [InlineData(Key.Up)]
+    public void HandleArrowKey_LeftAndUpWrapBackward(Key key)
+    {
+        var controller = new PieSelectionController();
+        PieSelectionController.Item[] items =
+        [
+            new(0, -10),
+            new(1, 100),
+            new(2, 170),
+        ];
+
+        controller.HandleArrowKey(Key.Right, items);
+        controller.HandleArrowKey(key, items);
+
+        Assert.Equal(2, controller.SelectedIndex);
+    }
+
+    [Theory]
+    [InlineData(Key.Right)]
+    [InlineData(Key.Down)]
+    public void HandleArrowKey_RightAndDownWrapForward(Key key)
+    {
+        var controller = new PieSelectionController();
+        PieSelectionController.Item[] items =
+        [
+            new(0, -10),
+            new(1, 100),
+            new(2, 170),
+        ];
+
+        controller.HandleArrowKey(Key.Left, items);
+        controller.HandleArrowKey(key, items);
+
+        Assert.Equal(0, controller.SelectedIndex);
+    }
+
+    [Fact]
+    public void EnsureSelectionIsValid_ResetsWhenSelectedIndexIsMissing()
+    {
+        var controller = new PieSelectionController();
+        PieSelectionController.Item[] originalItems =
+        [
+            new(0, -10),
+            new(1, 100),
+            new(2, 170),
+        ];
+        PieSelectionController.Item[] updatedItems =
+        [
+            new(0, -10),
+            new(2, 170),
+        ];
+
+        controller.HandleArrowKey(Key.Down, originalItems);
+        controller.EnsureSelectionIsValid(updatedItems);
+
+        Assert.Equal(PieSelectionController.NoSelection, controller.SelectedIndex);
+    }
+}

RadialActions/Pie/PieAnimationService.cs

@@ -0,0 +1,140 @@
+using System.Windows;
+using System.Windows.Media;
+using System.Windows.Media.Animation;
+
+namespace RadialActions;
+
+internal sealed class PieAnimationService
+{
+    public void ApplyBrushColor(
+        SolidColorBrush brush,
+        Color color,
+        bool animate,
+        Duration duration,
+        IEasingFunction easingFunction)
+    {
+        if (animate)
+        {
+            AnimateBrushColor(brush, color, duration, easingFunction);
+            return;
+        }
+
+        brush.BeginAnimation(SolidColorBrush.ColorProperty, null);
+        brush.Color = color;
+    }
+
+    public void AnimateBrushColor(
+        SolidColorBrush brush,
+        Color toColor,
+        Duration duration,
+        IEasingFunction easingFunction)
+    {
+        if (IsReducedMotionEnabled())
+        {
+            brush.BeginAnimation(SolidColorBrush.ColorProperty, null);
+            brush.Color = toColor;
+            return;
+        }
+
+        var colorAnimation = new ColorAnimation
+        {
+            To = toColor,
+            Duration = duration,
+            EasingFunction = easingFunction,
+        };
+
+        brush.BeginAnimation(SolidColorBrush.ColorProperty, colorAnimation, HandoffBehavior.SnapshotAndReplace);
+    }
+
+    public void AnimateOpacity(
+        UIElement element,
+        double toOpacity,
+        Duration duration,
+        IEasingFunction easingFunction,
+        Action onCompleted = null)
+    {
+        if (IsReducedMotionEnabled())
+        {
+            element.BeginAnimation(UIElement.OpacityProperty, null);
+            element.Opacity = toOpacity;
+            onCompleted?.Invoke();
+            return;
+        }
+
+        var opacityAnimation = new DoubleAnimation
+        {
+            To = toOpacity,
+            Duration = duration,
+            EasingFunction = easingFunction,
+        };
+
+        if (onCompleted != null)
+        {
+            opacityAnimation.Completed += (_, _) => onCompleted();
+        }
+
+        element.BeginAnimation(UIElement.OpacityProperty, opacityAnimation, HandoffBehavior.SnapshotAndReplace);
+    }
+
+    public void AnimateClickDown(UIElement target, Duration duration, IEasingFunction easingFunction)
+    {
+        if (target.RenderTransform is not ScaleTransform scaleTransform)
+        {
+            scaleTransform = new ScaleTransform(1, 1);
+            target.RenderTransform = scaleTransform;
+            target.RenderTransformOrigin = new Point(0.5, 0.5);
+        }
+
+        if (IsReducedMotionEnabled())
+        {
+            scaleTransform.BeginAnimation(ScaleTransform.ScaleXProperty, null);
+            scaleTransform.BeginAnimation(ScaleTransform.ScaleYProperty, null);
+            scaleTransform.ScaleX = 0.95;
+            scaleTransform.ScaleY = 0.95;
+            return;
+        }
+
+        var scaleAnimation = new DoubleAnimation
+        {
+            To = 0.95,
+            Duration = duration,
+            EasingFunction = easingFunction,
+            FillBehavior = FillBehavior.HoldEnd,
+        };
+
+        scaleTransform.BeginAnimation(ScaleTransform.ScaleXProperty, scaleAnimation, HandoffBehavior.SnapshotAndReplace);
+        scaleTransform.BeginAnimation(ScaleTransform.ScaleYProperty, scaleAnimation, HandoffBehavior.SnapshotAndReplace);
+    }
+
+    public void AnimateClickUp(UIElement target, Duration duration, IEasingFunction easingFunction)
+    {
+        if (target.RenderTransform is not ScaleTransform scaleTransform)
+        {
+            return;
+        }
+
+        if (IsReducedMotionEnabled())
+        {
+            scaleTransform.BeginAnimation(ScaleTransform.ScaleXProperty, null);
+            scaleTransform.BeginAnimation(ScaleTransform.ScaleYProperty, null);
+            scaleTransform.ScaleX = 1;
+            scaleTransform.ScaleY = 1;
+            return;
+        }
+
+        var scaleAnimation = new DoubleAnimation
+        {
+            To = 1,
+            Duration = duration,
+            EasingFunction = easingFunction,
+        };
+
+        scaleTransform.BeginAnimation(ScaleTransform.ScaleXProperty, scaleAnimation, HandoffBehavior.SnapshotAndReplace);
+        scaleTransform.BeginAnimation(ScaleTransform.ScaleYProperty, scaleAnimation, HandoffBehavior.SnapshotAndReplace);
+    }
+
+    public static bool IsReducedMotionEnabled()
+    {
+        return !SystemParameters.ClientAreaAnimation;
+    }
+}

RadialActions/Pie/PieCenterVisual.cs

@@ -0,0 +1,12 @@
+using System.Windows.Controls;
+using System.Windows.Media;
+
+namespace RadialActions;
+
+internal sealed class PieCenterVisual
+{
+    public required Grid Target { get; init; }
+    public required SolidColorBrush FillBrush { get; init; }
+    public required SolidColorBrush StrokeBrush { get; init; }
+    public required TextBlock Icon { get; init; }
+}