Implement incompatibility-displaying variant of mod panel

osu.Game.Tests/Visual/UserInterface/TestSceneModPanel.cs

@@ -1,14 +1,17 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
 using NUnit.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Game.Overlays;
 using osu.Game.Overlays.Mods;
+using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Osu.Mods;
 using osuTK;
+using osuTK.Input;
 
 namespace osu.Game.Tests.Visual.UserInterface
 {
@@ -38,5 +41,41 @@ namespace osu.Game.Tests.Visual.UserInterface
                 }
             });
         }
+
+        [Test]
+        public void TestIncompatibilityDisplay()
+        {
+            IncompatibilityDisplayingModPanel panel = null;
+
+            AddStep("create panel with DT", () => Child = panel = new IncompatibilityDisplayingModPanel(new OsuModDoubleTime())
+            {
+                Anchor = Anchor.Centre,
+                Origin = Anchor.Centre,
+                RelativeSizeAxes = Axes.None,
+                Width = 300
+            });
+
+            clickPanel();
+            AddAssert("panel active", () => panel.Active.Value);
+
+            clickPanel();
+            AddAssert("panel not active", () => !panel.Active.Value);
+
+            AddStep("set incompatible mod", () => SelectedMods.Value = new[] { new OsuModHalfTime() });
+
+            clickPanel();
+            AddAssert("panel not active", () => !panel.Active.Value);
+
+            AddStep("reset mods", () => SelectedMods.Value = Array.Empty<Mod>());
+
+            clickPanel();
+            AddAssert("panel active", () => panel.Active.Value);
+
+            void clickPanel() => AddStep("click panel", () =>
+            {
+                InputManager.MoveMouseTo(panel);
+                InputManager.Click(MouseButton.Left);
+            });
+        }
     }
 }

osu.Game/Overlays/Mods/IncompatibilityDisplayingModPanel.cs

@@ -0,0 +1,88 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Colour;
+using osu.Framework.Graphics.Cursor;
+using osu.Framework.Input.Events;
+using osu.Game.Rulesets.Mods;
+using osu.Game.Utils;
+
+namespace osu.Game.Overlays.Mods
+{
+    public class IncompatibilityDisplayingModPanel : ModPanel, IHasCustomTooltip<Mod>
+    {
+        private readonly BindableBool incompatible = new BindableBool();
+
+        [Resolved]
+        private Bindable<IReadOnlyList<Mod>> selectedMods { get; set; }
+
+        public IncompatibilityDisplayingModPanel(Mod mod)
+            : base(mod)
+        {
+        }
+
+        protected override void LoadComplete()
+        {
+            selectedMods.BindValueChanged(_ => updateIncompatibility(), true);
+            incompatible.BindValueChanged(_ => Scheduler.AddOnce(UpdateState));
+            // base call will run `UpdateState()` first time and finish transforms.
+            base.LoadComplete();
+        }
+
+        private void updateIncompatibility()
+        {
+            incompatible.Value = selectedMods.Value.Count > 0 && !selectedMods.Value.Contains(Mod) && !ModUtils.CheckCompatibleSet(selectedMods.Value.Append(Mod));
+        }
+
+        protected override void UpdateState()
+        {
+            Action = incompatible.Value ? () => { } : (Action)Active.Toggle;
+
+            if (incompatible.Value)
+            {
+                Colour4 backgroundColour = ColourProvider.Background5;
+                Colour4 textBackgroundColour = ColourProvider.Background4;
+
+                Content.TransformTo(nameof(BorderColour), ColourInfo.GradientVertical(backgroundColour, textBackgroundColour), TRANSITION_DURATION, Easing.OutQuint);
+                Background.FadeColour(backgroundColour, TRANSITION_DURATION, Easing.OutQuint);
+
+                SwitchContainer.ResizeWidthTo(IDLE_SWITCH_WIDTH, TRANSITION_DURATION, Easing.OutQuint);
+                SwitchContainer.FadeColour(Colour4.Gray, TRANSITION_DURATION, Easing.OutQuint);
+                MainContentContainer.TransformTo(nameof(Padding), new MarginPadding
+                {
+                    Left = IDLE_SWITCH_WIDTH,
+                    Right = CORNER_RADIUS
+                }, TRANSITION_DURATION, Easing.OutQuint);
+
+                TextBackground.FadeColour(textBackgroundColour, TRANSITION_DURATION, Easing.OutQuint);
+                TextFlow.FadeColour(Colour4.White.Opacity(0.5f), TRANSITION_DURATION, Easing.OutQuint);
+                return;
+            }
+
+            SwitchContainer.FadeColour(Colour4.White, TRANSITION_DURATION, Easing.OutQuint);
+            base.UpdateState();
+        }
+
+        protected override bool OnMouseDown(MouseDownEvent e)
+        {
+            if (incompatible.Value)
+                return true; // bypasses base call purposely in order to not play out the intermediate state animation.
+
+            return base.OnMouseDown(e);
+        }
+
+        #region IHasCustomTooltip
+
+        public ITooltip<Mod> GetCustomTooltip() => new IncompatibilityDisplayingTooltip();
+
+        public Mod TooltipContent => Mod;
+
+        #endregion
+    }
+}