Add styling for footnote links

osu.Game/Graphics/Containers/Markdown/Footnotes/OsuMarkdownFootnoteLink.cs

@@ -0,0 +1,70 @@
+// 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.Collections.Generic;
+using Markdig.Extensions.Footnotes;
+using osu.Framework.Allocation;
+using osu.Framework.Extensions.IEnumerableExtensions;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers.Markdown;
+using osu.Framework.Graphics.Cursor;
+using osu.Framework.Graphics.Sprites;
+using osu.Framework.Localisation;
+using osu.Game.Overlays;
+
+namespace osu.Game.Graphics.Containers.Markdown.Footnotes
+{
+    public partial class OsuMarkdownFootnoteLink : OsuHoverContainer, IHasCustomTooltip
+    {
+        private readonly FootnoteLink footnoteLink;
+
+        private SpriteText spriteText = null!;
+
+        [Resolved]
+        private IMarkdownTextComponent parentTextComponent { get; set; } = null!;
+
+        [Resolved]
+        private OverlayColourProvider colourProvider { get; set; } = null!;
+
+        [Resolved]
+        private OsuMarkdownContainer markdownContainer { get; set; } = null!;
+
+        protected override IEnumerable<Drawable> EffectTargets => spriteText.Yield();
+
+        public OsuMarkdownFootnoteLink(FootnoteLink footnoteLink)
+        {
+            this.footnoteLink = footnoteLink;
+
+            AutoSizeAxes = Axes.Both;
+            Action = () => { }; // TODO
+        }
+
+        [BackgroundDependencyLoader]
+        private void load()
+        {
+            IdleColour = colourProvider.Light2;
+            HoverColour = colourProvider.Light1;
+
+            spriteText = parentTextComponent.CreateSpriteText();
+
+            Add(spriteText.With(t =>
+            {
+                float baseSize = t.Font.Size;
+                t.Font = t.Font.With(size: baseSize * 0.58f);
+                t.Margin = new MarginPadding { Bottom = 0.33f * baseSize };
+                t.Text = LocalisableString.Format("[{0}]", footnoteLink.Index);
+            }));
+        }
+
+        public object TooltipContent
+        {
+            get
+            {
+                var span = footnoteLink.Footnote.LastChild.Span;
+                return markdownContainer.Text.Substring(span.Start, span.Length);
+            }
+        }
+
+        public ITooltip GetCustomTooltip() => new OsuMarkdownFootnoteTooltip(colourProvider);
+    }
+}

osu.Game/Graphics/Containers/Markdown/Footnotes/OsuMarkdownFootnoteTooltip.cs

@@ -0,0 +1,76 @@
+// 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 Markdig.Extensions.Footnotes;
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Containers.Markdown;
+using osu.Framework.Graphics.Cursor;
+using osu.Framework.Graphics.Shapes;
+using osu.Game.Overlays;
+using osuTK;
+
+namespace osu.Game.Graphics.Containers.Markdown.Footnotes
+{
+    public partial class OsuMarkdownFootnoteTooltip : CompositeDrawable, ITooltip
+    {
+        private readonly FootnoteMarkdownContainer markdownContainer;
+
+        [Cached]
+        private OverlayColourProvider colourProvider;
+
+        public OsuMarkdownFootnoteTooltip(OverlayColourProvider colourProvider)
+        {
+            this.colourProvider = colourProvider;
+
+            Masking = true;
+            Width = 200;
+            AutoSizeAxes = Axes.Y;
+            CornerRadius = 4;
+
+            InternalChildren = new Drawable[]
+            {
+                new Box
+                {
+                    RelativeSizeAxes = Axes.Both,
+                    Colour = colourProvider.Background6
+                },
+                markdownContainer = new FootnoteMarkdownContainer
+                {
+                    RelativeSizeAxes = Axes.X,
+                    AutoSizeAxes = Axes.Y,
+                    DocumentMargin = new MarginPadding(),
+                    DocumentPadding = new MarginPadding { Horizontal = 10, Vertical = 5 }
+                }
+            };
+        }
+
+        public void Move(Vector2 pos) => Position = pos;
+
+        public void SetContent(object content) => markdownContainer.SetContent((string)content);
+
+        private partial class FootnoteMarkdownContainer : OsuMarkdownContainer
+        {
+            private string? lastFootnote;
+
+            public void SetContent(string footnote)
+            {
+                if (footnote == lastFootnote)
+                    return;
+
+                lastFootnote = Text = footnote;
+            }
+
+            public override MarkdownTextFlowContainer CreateTextFlow() => new FootnoteMarkdownTextFlowContainer();
+        }
+
+        private partial class FootnoteMarkdownTextFlowContainer : OsuMarkdownTextFlowContainer
+        {
+            protected override void AddFootnoteBacklink(FootnoteLink footnoteBacklink)
+            {
+                // we don't want footnote backlinks to show up in tooltips.
+            }
+        }
+    }
+}

osu.Game/Graphics/Containers/Markdown/OsuMarkdownContainer.cs

@@ -11,6 +11,7 @@ using Markdig.Extensions.Footnotes;
 using Markdig.Extensions.Tables;
 using Markdig.Extensions.Yaml;
 using Markdig.Syntax;
+using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Containers.Markdown;
@@ -19,6 +20,7 @@ using osu.Game.Graphics.Sprites;
 
 namespace osu.Game.Graphics.Containers.Markdown
 {
+    [Cached]
     public partial class OsuMarkdownContainer : MarkdownContainer
     {
         /// <summary>

osu.Game/Graphics/Containers/Markdown/OsuMarkdownTextFlowContainer.cs

@@ -6,6 +6,7 @@
 using System;
 using System.Linq;
 using Markdig.Extensions.CustomContainers;
+using Markdig.Extensions.Footnotes;
 using Markdig.Syntax.Inlines;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
@@ -13,6 +14,7 @@ using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Containers.Markdown;
 using osu.Framework.Graphics.Shapes;
 using osu.Framework.Graphics.Sprites;
+using osu.Game.Graphics.Containers.Markdown.Footnotes;
 using osu.Game.Overlays;
 using osu.Game.Users;
 using osu.Game.Users.Drawables;
@@ -36,6 +38,8 @@ namespace osu.Game.Graphics.Containers.Markdown
             Text = codeInline.Content
         });
 
+        protected override void AddFootnoteLink(FootnoteLink footnoteLink) => AddDrawable(new OsuMarkdownFootnoteLink(footnoteLink));
+
         protected override SpriteText CreateEmphasisedSpriteText(bool bold, bool italic)
             => CreateSpriteText().With(t => t.Font = t.Font.With(weight: bold ? FontWeight.Bold : FontWeight.Regular, italics: italic));