From 982e3b38c35e27ca2ec66b9032d99e6233f9e6d1 Mon Sep 17 00:00:00 2001
From: "D. Moonfire" <d.moonfire@moonfire.us>
Date: Sat, 24 Dec 2022 00:38:24 -0600
Subject: [PATCH] feat(markdown): implemented expanding single link list items

---
 .../MakeSingleLinkListItems.cs                | 103 ++++++++++++++++++
 .../MfGames.Nitride.Markdown.csproj           |   1 +
 .../MakeSingleLinkListItemsTests.cs           | 100 +++++++++++++++++
 .../MarkdownTestContext.cs                    |  22 ++++
 4 files changed, 226 insertions(+)
 create mode 100644 src/MfGames.Nitride.Markdown/MakeSingleLinkListItems.cs
 create mode 100644 tests/MfGames.Nitride.Markdown.Tests/MakeSingleLinkListItemsTests.cs
 create mode 100644 tests/MfGames.Nitride.Markdown.Tests/MarkdownTestContext.cs

diff --git a/src/MfGames.Nitride.Markdown/MakeSingleLinkListItems.cs b/src/MfGames.Nitride.Markdown/MakeSingleLinkListItems.cs
new file mode 100644
index 0000000..85ab750
--- /dev/null
+++ b/src/MfGames.Nitride.Markdown/MakeSingleLinkListItems.cs
@@ -0,0 +1,103 @@
+using System.Collections.Generic;
+using System.Linq;
+using System.Text.RegularExpressions;
+
+using MfGames.Gallium;
+using MfGames.Nitride.Contents;
+using MfGames.Nitride.Slugs;
+
+namespace MfGames.Nitride.Markdown;
+
+/// <summary>
+/// An operation that turns list items that starts with a link into a single
+/// link for the entire list item, even if there are additional links in the
+/// list.
+/// </summary>
+public class MakeSingleLinkListItems : IOperation
+{
+    private readonly ISlugConverter slugs;
+
+    public MakeSingleLinkListItems(ISlugConverter slugs)
+    {
+        this.slugs = slugs;
+    }
+
+    /// <inheritdoc />
+    public IEnumerable<Entity> Run(IEnumerable<Entity> input)
+    {
+        return input
+            .SelectManyEntity<IsMarkdown>(
+                x => x
+                    .Select(this.MakeSingleLinkLists));
+    }
+
+    /// <summary>
+    /// This turns all links that start with a link into a single link while
+    /// removing all trailing links within the line. This is to simplify the
+    /// rendering of the link on page.
+    /// </summary>
+    private Entity MakeSingleLinkLists(Entity entity)
+    {
+        string content = entity.GetText()!;
+
+        string output = Regex.Replace(
+            content,
+            @"- \[\[(?<label>[^\]]+?)\]\](?<post>[^\n]+)\n",
+            match =>
+            {
+                string wiki = match.Groups["label"].ToString();
+                string path = string.Format(
+                    "/{0}/",
+                    this.slugs.ToSlug(wiki.Split('|').First()));
+                string label = wiki.Split('|').Last();
+                string after = match.Groups["post"].ToString();
+                string post = this.RemoveLinks(after);
+                string value = $"- [{label}{post}]({path})\n";
+
+                return value;
+            });
+
+        output = Regex.Replace(
+            output,
+            @"- \[(?<label>[^\]]+?)\]\((?<path>[^\)]+?)\)(?<post>[^\n]+)\n",
+            match =>
+            {
+                string label = match.Groups["label"].ToString();
+                string path = match.Groups["path"].ToString();
+                string after = match.Groups["post"].ToString();
+                string post = this.RemoveLinks(after);
+                string value = $"- [{label}{post}]({path})\n";
+
+                return value;
+            });
+
+        return entity.SetTextContent(output);
+    }
+
+    /// <summary>
+    /// Removes a normal link and replaces it with the text.
+    /// </summary>
+    private string RemoveLinks(string input)
+    {
+        string output = Regex.Replace(
+            input,
+            @"\[\[(?<label>[^\]]+)\]\]",
+            match =>
+            {
+                string link1 = match.Groups["label"].ToString();
+                string path1 = string.Format(
+                    "/{0}/",
+                    this.slugs.ToSlug(link1.Split('|').First()));
+                string label1 = link1.Split('|').Last();
+
+                return label1;
+            });
+
+        output = Regex.Replace(
+            output,
+            @"\[(?<label>[^\]]+)\]\([^)]+\)",
+            match => match.Groups["label"].ToString());
+
+        return output;
+    }
+}
diff --git a/src/MfGames.Nitride.Markdown/MfGames.Nitride.Markdown.csproj b/src/MfGames.Nitride.Markdown/MfGames.Nitride.Markdown.csproj
index c8928df..1423891 100644
--- a/src/MfGames.Nitride.Markdown/MfGames.Nitride.Markdown.csproj
+++ b/src/MfGames.Nitride.Markdown/MfGames.Nitride.Markdown.csproj
@@ -12,6 +12,7 @@
   <ItemGroup>
     <ProjectReference Include="..\MfGames.Nitride.Gemtext\MfGames.Nitride.Gemtext.csproj" />
     <ProjectReference Include="..\MfGames.Nitride.Html\MfGames.Nitride.Html.csproj" />
+    <ProjectReference Include="..\MfGames.Nitride.Slugs\MfGames.Nitride.Slugs.csproj" />
     <ProjectReference Include="..\MfGames.Nitride\MfGames.Nitride.csproj" />
   </ItemGroup>
 
diff --git a/tests/MfGames.Nitride.Markdown.Tests/MakeSingleLinkListItemsTests.cs b/tests/MfGames.Nitride.Markdown.Tests/MakeSingleLinkListItemsTests.cs
new file mode 100644
index 0000000..bfde40f
--- /dev/null
+++ b/tests/MfGames.Nitride.Markdown.Tests/MakeSingleLinkListItemsTests.cs
@@ -0,0 +1,100 @@
+using System.Collections.Generic;
+using System.Linq;
+
+using MfGames.Gallium;
+using MfGames.Nitride.Contents;
+using MfGames.Nitride.Markdown;
+using MfGames.Nitride.Tests;
+using MfGames.TestSetup;
+
+using Xunit;
+using Xunit.Abstractions;
+
+namespace MfGames.Nitride.Slugs.Tests;
+
+/// <summary>
+/// Tests the functionality of the WriteFiles().
+/// </summary>
+public class MakeSingleLinkListItemsTests : TestBase<MarkdownTestContext>
+{
+    public MakeSingleLinkListItemsTests(ITestOutputHelper output)
+        : base(output)
+    {
+    }
+
+    [Fact]
+    public void AlreadyFullMarkdownLink()
+    {
+        using MarkdownTestContext context = this.CreateContext();
+
+        List<Entity> input = new()
+        {
+            new Entity()
+                .Set(IsMarkdown.Instance)
+                .SetTextContent("- [Empty](link)"),
+        };
+        MakeSingleLinkListItems?
+            op = context.Resolve<MakeSingleLinkListItems>();
+        IEnumerable<Entity> output = op.Run(input);
+        string content = output.First().GetText()!.Trim();
+
+        Assert.Equal("- [Empty](link)", content);
+    }
+
+    [Fact]
+    public void ExtendSingleMarkdownLink()
+    {
+        using MarkdownTestContext context = this.CreateContext();
+
+        List<Entity> input = new()
+        {
+            new Entity()
+                .Set(IsMarkdown.Instance)
+                .SetTextContent("- [Empty](link) space"),
+        };
+        MakeSingleLinkListItems?
+            op = context.Resolve<MakeSingleLinkListItems>();
+        IEnumerable<Entity> output = op.Run(input);
+        string content = output.First().GetText()!.Trim();
+
+        Assert.Equal("- [Empty space](link)", content);
+    }
+
+    [Fact]
+    public void NoLinksNoChange()
+    {
+        using MarkdownTestContext context = this.CreateContext();
+
+        List<Entity> input = new()
+        {
+            new Entity()
+                .Set(IsMarkdown.Instance)
+                .SetTextContent("- Empty"),
+        };
+        MakeSingleLinkListItems?
+            op = context.Resolve<MakeSingleLinkListItems>();
+        IEnumerable<Entity> output = op.Run(input);
+        string content = output.First().GetText()!.Trim();
+
+        Assert.Equal("- Empty", content);
+    }
+
+    [Fact]
+    public void RemoveSecondMarkdownLink()
+    {
+        using MarkdownTestContext context = this.CreateContext();
+
+        List<Entity> input = new()
+        {
+            new Entity()
+                .Set(IsMarkdown.Instance)
+                .SetTextContent("- [Empty](link) [space](link2)"),
+        };
+        MakeSingleLinkListItems?
+            op = context.Resolve<MakeSingleLinkListItems>();
+        IEnumerable<Entity> output = op.Run(input);
+        string content = output.First().GetText()!.Trim();
+
+        Assert.Equal("- [Empty space](link)", content);
+    }
+}
diff --git a/tests/MfGames.Nitride.Markdown.Tests/MarkdownTestContext.cs b/tests/MfGames.Nitride.Markdown.Tests/MarkdownTestContext.cs
new file mode 100644
index 0000000..1a706e3
--- /dev/null
+++ b/tests/MfGames.Nitride.Markdown.Tests/MarkdownTestContext.cs
@@ -0,0 +1,22 @@
+using Autofac;
+
+using MfGames.Nitride.Markdown;
+using MfGames.Nitride.Tests;
+
+namespace MfGames.Nitride.Slugs.Tests;
+
+public class MarkdownTestContext : NitrideTestContext
+{
+    /// <inheritdoc />
+    protected override void ConfigureContainer(ContainerBuilder builder)
+    {
+        base.ConfigureContainer(builder);
+        builder.RegisterModule<NitrideSlugsModule>();
+        builder.RegisterModule<NitrideMarkdownModule>();
+
+        builder
+            .RegisterType<SimpleSlugConverter>()
+            .As<ISlugConverter>()
+            .SingleInstance();
+    }
+}