fix: move sender name to Reply-To

dear god help me

.github/workflows/dotnet.yml

@@ -10,16 +10,19 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v2
+    - name: Checkout
+      uses: actions/checkout@v4
+
     - name: Setup .NET
-      uses: actions/setup-dotnet@v3
+      uses: actions/setup-dotnet@v4
       with:
         dotnet-version: 8.0.x
-    - name: Add NuGet source
+
-      run: dotnet nuget add source --username oliverbooth --password ${{ secrets.GITHUB_TOKEN }} --store-password-in-clear-text --name github "https://nuget.pkg.github.com/oliverbooth/index.json"
     - name: Restore dependencies
       run: dotnet restore
+
     - name: Build
       run: dotnet build --no-restore --configuration Release
+
     - name: Test
       run: dotnet test --no-build --verbosity normal

.github/workflows/prerelease.yml

@@ -12,16 +12,13 @@ jobs:
 
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup .NET
-      uses: actions/setup-dotnet@v3
+      uses: actions/setup-dotnet@v4
       with:
         dotnet-version: 8.0.x
 
-    - name: Add GitHub NuGet source
-      run: dotnet nuget add source --username oliverbooth --password ${{ secrets.GITHUB_TOKEN }} --store-password-in-clear-text --name github "https://nuget.pkg.github.com/oliverbooth/index.json"
-
     - name: Restore dependencies
       run: dotnet restore
 

.github/workflows/release.yml

@@ -12,16 +12,13 @@ jobs:
 
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup .NET
-      uses: actions/setup-dotnet@v3
+      uses: actions/setup-dotnet@v4
       with:
         dotnet-version: 8.0.x
 
-    - name: Add GitHub NuGet source
-      run: dotnet nuget add source --username oliverbooth --password ${{ secrets.GITHUB_TOKEN }} --store-password-in-clear-text --name github "https://nuget.pkg.github.com/oliverbooth/index.json"
-
     - name: Restore dependencies
       run: dotnet restore
 

OliverBooth.Common/Data/Blog/IBlogAuthor.cs

@@ -1,4 +1,4 @@
-namespace OliverBooth.Data.Blog;
+namespace OliverBooth.Common.Data.Blog;
 
 /// <summary>
 ///     Represents the author of a blog post.

OliverBooth.Common/Data/Blog/IBlogPost.cs

@@ -1,4 +1,4 @@
-namespace OliverBooth.Data.Blog;
+namespace OliverBooth.Common.Data.Blog;
 
 /// <summary>
 ///     Represents a blog post.
@@ -25,6 +25,12 @@ public interface IBlogPost
     /// </value>
     bool EnableComments { get; }
 
+    /// <summary>
+    ///     Gets the excerpt of this post, if it has one.
+    /// </summary>
+    /// <value>The excerpt, or <see langword="null" /> if this post has no excerpt.</value>
+    string? Excerpt { get; }
+
     /// <summary>
     ///     Gets the ID of the post.
     /// </summary>
@@ -85,7 +91,7 @@ public interface IBlogPost
     ///     Gets the visibility of the post.
     /// </summary>
     /// <value>The visibility of the post.</value>
-    BlogPostVisibility Visibility { get; }
+    Visibility Visibility { get; }
 
     /// <summary>
     ///     Gets the WordPress ID of the post.

OliverBooth.Common/Data/Blog/ILegacyComment.cs

@@ -0,0 +1,54 @@
+namespace OliverBooth.Common.Data.Blog;
+
+/// <summary>
+///     Represents a comment that was posted on a legacy comment framework.
+/// </summary>
+public interface ILegacyComment
+{
+    /// <summary>
+    ///     Gets the PNG-encoded avatar of the author.
+    /// </summary>
+    /// <value>The author's avatar.</value>
+    string? Avatar { get; }
+
+    /// <summary>
+    ///     Gets the name of the comment's author.
+    /// </summary>
+    /// <value>The author's name.</value>
+    string Author { get; }
+
+    /// <summary>
+    ///     Gets the body of the comment.
+    /// </summary>
+    /// <value>The comment body.</value>
+    string Body { get; }
+
+    /// <summary>
+    ///     Gets the date and time at which this comment was posted.
+    /// </summary>
+    /// <value>The creation timestamp.</value>
+    DateTimeOffset CreatedAt { get; }
+
+    /// <summary>
+    ///     Gets the ID of this comment.
+    /// </summary>
+    Guid Id { get; }
+
+    /// <summary>
+    ///     Gets the ID of the comment this comment is replying to.
+    /// </summary>
+    /// <value>The parent comment ID, or <see langword="null" /> if this comment is not a reply.</value>
+    Guid? ParentComment { get; }
+
+    /// <summary>
+    ///     Gets the ID of the post to which this comment was posted.
+    /// </summary>
+    /// <value>The post ID.</value>
+    Guid PostId { get; }
+
+    /// <summary>
+    ///     Gets the avatar URL of the comment's author.
+    /// </summary>
+    /// <returns>The avatar URL.</returns>
+    string GetAvatarUrl();
+}

OliverBooth.Common/Data/Blog/IUser.cs

@@ -1,4 +1,4 @@
-namespace OliverBooth.Data.Blog;
+namespace OliverBooth.Common.Data.Blog;
 
 /// <summary>
 ///     Represents a user which can log in to the blog.

OliverBooth.Common/Data/Mastodon/AttachmentType.cs

@@ -1,4 +1,4 @@
-namespace OliverBooth.Data.Mastodon;
+namespace OliverBooth.Common.Data.Mastodon;
 
 public enum AttachmentType
 {

OliverBooth.Common/Data/Mastodon/IMastodonStatus.cs

@@ -0,0 +1,31 @@
+namespace OliverBooth.Common.Data.Mastodon;
+
+/// <summary>
+///     Represents a status on Mastodon.
+/// </summary>
+public interface IMastodonStatus
+{
+    /// <summary>
+    ///     Gets the content of the status.
+    /// </summary>
+    /// <value>The content.</value>
+    string Content { get; }
+
+    /// <summary>
+    ///     Gets the date and time at which this status was posted.
+    /// </summary>
+    /// <value>The post timestamp.</value>
+    DateTimeOffset CreatedAt { get; }
+
+    /// <summary>
+    ///     Gets the media attachments for this status.
+    /// </summary>
+    /// <value>The media attachments.</value>
+    IReadOnlyList<MediaAttachment> MediaAttachments { get; }
+
+    /// <summary>
+    ///     Gets the original URI of the status.
+    /// </summary>
+    /// <value>The original URI.</value>
+    Uri OriginalUri { get; }
+}

OliverBooth.Common/Data/Mastodon/MediaAttachment.cs

@@ -1,4 +1,4 @@
-namespace OliverBooth.Data.Mastodon;
+namespace OliverBooth.Common.Data.Mastodon;
 
 public sealed class MediaAttachment
 {

OliverBooth.Common/Data/Visibility.cs

@@ -1,10 +1,15 @@
-namespace OliverBooth.Data.Blog;
+namespace OliverBooth.Common.Data;
 
 /// <summary>
 ///     An enumeration of the possible visibilities of a blog post.
 /// </summary>
-public enum BlogPostVisibility
+public enum Visibility
 {
+    /// <summary>
+    ///     Used for filtering results. Represents all visibilities.
+    /// </summary>
+    None = -1,
+
     /// <summary>
     ///     The post is private and only visible to the author, or those with the password.
     /// </summary>

OliverBooth.Common/Data/Web/BookState.cs

@@ -1,4 +1,4 @@
-namespace OliverBooth.Data.Web;
+namespace OliverBooth.Common.Data.Web;
 
 /// <summary>
 ///     Represents the state of a book.

OliverBooth.Common/Data/Web/IBlacklistEntry.cs

@@ -1,4 +1,4 @@
-namespace OliverBooth.Data.Web;
+namespace OliverBooth.Common.Data.Web;
 
 /// <summary>
 ///     Represents an entry in the blacklist.

OliverBooth.Common/Data/Web/IBook.cs

@@ -1,4 +1,4 @@
-namespace OliverBooth.Data.Web;
+namespace OliverBooth.Common.Data.Web;
 
 /// <summary>
 ///     Represents a book.

OliverBooth.Common/Data/Web/ICodeSnippet.cs

@@ -0,0 +1,25 @@
+namespace OliverBooth.Common.Data.Web;
+
+/// <summary>
+///     Represents a code snippet.
+/// </summary>
+public interface ICodeSnippet
+{
+    /// <summary>
+    ///     Gets the content for this snippet.
+    /// </summary>
+    /// <value>The content for this snippet</value>
+    string Content { get; }
+
+    /// <summary>
+    ///     Gets the ID for this snippet.
+    /// </summary>
+    /// <value>The ID for this snippet</value>
+    int Id { get; }
+
+    /// <summary>
+    ///     Gets the language for this snippet.
+    /// </summary>
+    /// <value>The language for this snippet</value>
+    string Language { get; }
+}

OliverBooth.Common/Data/Web/IProgrammingLanguage.cs

@@ -1,4 +1,4 @@
-namespace OliverBooth.Data.Web;
+namespace OliverBooth.Common.Data.Web;
 
 /// <summary>
 ///     Represents a programming language.

OliverBooth.Common/Data/Web/IProject.cs

@@ -1,4 +1,4 @@
-namespace OliverBooth.Data.Web;
+namespace OliverBooth.Common.Data.Web;
 
 /// <summary>
 ///     Represents a project.

OliverBooth.Common/Data/Web/ITemplate.cs

@@ -1,4 +1,4 @@
-namespace OliverBooth.Data.Web;
+namespace OliverBooth.Common.Data.Web;
 
 /// <summary>
 ///     Represents a template.

OliverBooth.Common/Data/Web/ITutorialArticle.cs

@@ -0,0 +1,99 @@
+namespace OliverBooth.Common.Data.Web;
+
+/// <summary>
+///     Represents a tutorial article.
+/// </summary>
+public interface ITutorialArticle
+{
+    /// <summary>
+    ///     Gets the body of this article.
+    /// </summary>
+    /// <value>The body.</value>
+    string Body { get; }
+
+    /// <summary>
+    ///     Gets a value indicating whether comments are enabled for the article.
+    /// </summary>
+    /// <value>
+    ///     <see langword="true" /> if comments are enabled for the article; otherwise, <see langword="false" />.
+    /// </value>
+    bool EnableComments { get; }
+
+    /// <summary>
+    ///     Gets the excerpt of this article, if it has one.
+    /// </summary>
+    /// <value>The excerpt, or <see langword="null" /> if this article has no excerpt.</value>
+    string? Excerpt { get; }
+
+    /// <summary>
+    ///     Gets the ID of the folder this article is contained within.
+    /// </summary>
+    /// <value>The ID of the folder.</value>
+    int Folder { get; }
+
+    /// <summary>
+    ///     Gets a value indicating whether this article is part of a multi-part series.
+    /// </summary>
+    /// <value><see langword="true" /> if this article has additional parts; otherwise, <see langword="false" />.</value>
+    bool HasOtherParts { get; }
+
+    /// <summary>
+    ///     Gets the ID of this article.
+    /// </summary>
+    /// <value>The ID.</value>
+    int Id { get; }
+
+    /// <summary>
+    ///     Gets the ID of the next article to this one.
+    /// </summary>
+    /// <value>The next part ID.</value>
+    int? NextPart { get; }
+
+    /// <summary>
+    ///     Gets the URL of the article's preview image.
+    /// </summary>
+    /// <value>The preview image URL.</value>
+    Uri? PreviewImageUrl { get; }
+
+    /// <summary>
+    ///     Gets the ID of the previous article to this one.
+    /// </summary>
+    /// <value>The previous part ID.</value>
+    int? PreviousPart { get; }
+
+    /// <summary>
+    ///     Gets the date and time at which this article was published.
+    /// </summary>
+    /// <value>The publish timestamp.</value>
+    DateTimeOffset Published { get; }
+
+    /// <summary>
+    ///     Gets the ID of the post that was redirected to this article.
+    /// </summary>
+    /// <value>The source redirect post ID.</value>
+    Guid? RedirectFrom { get; }
+
+    /// <summary>
+    ///     Gets the slug of this article.
+    /// </summary>
+    /// <value>The slug.</value>
+    string Slug { get; }
+
+    /// <summary>
+    ///     Gets the title of this article.
+    /// </summary>
+    /// <value>The title.</value>
+    string Title { get; }
+
+    /// <summary>
+    ///     Gets the date and time at which this article was updated.
+    /// </summary>
+    /// <value>The update timestamp, or <see langword="null" /> if this article has not been updated.</value>
+    DateTimeOffset? Updated { get; }
+
+    /// <summary>
+    ///     Gets the visibility of this article.
+    /// </summary>
+    /// <value>The visibility of the article.</value>
+    Visibility Visibility { get; }
+}

OliverBooth.Common/Data/Web/ITutorialFolder.cs

@@ -0,0 +1,43 @@
+namespace OliverBooth.Common.Data.Web;
+
+/// <summary>
+///     Represents a folder for tutorial articles.
+/// </summary>
+public interface ITutorialFolder
+{
+    /// <summary>
+    ///     Gets the ID of this folder.
+    /// </summary>
+    /// <value>The ID of the folder.</value>
+    int Id { get; }
+
+    /// <summary>
+    ///     Gets the ID of this folder's parent.
+    /// </summary>
+    /// <value>The ID of the parent, or <see langword="null" /> if this folder is at the root.</value>
+    int? Parent { get; }
+
+    /// <summary>
+    ///     Gets the URL of the folder's preview image.
+    /// </summary>
+    /// <value>The preview image URL.</value>
+    Uri? PreviewImageUrl { get; }
+
+    /// <summary>
+    ///     Gets the slug of this folder.
+    /// </summary>
+    /// <value>The slug.</value>
+    string Slug { get; }
+
+    /// <summary>
+    ///     Gets the title of this folder.
+    /// </summary>
+    /// <value>The title.</value>
+    string Title { get; }
+
+    /// <summary>
+    ///     Gets the visibility of this article.
+    /// </summary>
+    /// <value>The visibility of the article.</value>
+    Visibility Visibility { get; }
+}

OliverBooth.Common/Data/Web/ProjectStatus.cs

@@ -1,6 +1,6 @@
 using System.ComponentModel;
 
-namespace OliverBooth.Data.Web;
+namespace OliverBooth.Common.Data.Web;
 
 /// <summary>
 ///     Represents the status of a project.

OliverBooth.Common/OliverBooth.Common.csproj

@@ -0,0 +1,15 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFramework>net8.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+    <ItemGroup>
+        <PackageReference Include="HtmlAgilityPack" Version="1.11.59"/>
+        <PackageReference Include="Humanizer.Core" Version="2.14.1"/>
+        <PackageReference Include="ZString" Version="2.5.1"/>
+    </ItemGroup>
+
+</Project>

OliverBooth.Common/Services/IBlogPostService.cs

@@ -1,7 +1,8 @@
 using System.Diagnostics.CodeAnalysis;
-using OliverBooth.Data.Blog;
+using OliverBooth.Common.Data;
+using OliverBooth.Common.Data.Blog;
 
-namespace OliverBooth.Services;
+namespace OliverBooth.Common.Services;
 
 /// <summary>
 ///     Represents a service for managing blog posts.
@@ -22,8 +23,10 @@ public interface IBlogPostService
     /// <summary>
     ///     Returns the total number of blog posts.
     /// </summary>
+    /// <param name="visibility">The post visibility filter.</param>
+    /// <param name="tags">The tags of the posts to return.</param>
     /// <returns>The total number of blog posts.</returns>
-    int GetBlogPostCount();
+    int GetBlogPostCount(Visibility visibility = Visibility.None, string[]? tags = null);
 
     /// <summary>
     ///     Returns a collection of blog posts from the specified page, optionally limiting the number of posts
@@ -31,8 +34,30 @@ public interface IBlogPostService
     /// </summary>
     /// <param name="page">The zero-based index of the page to return.</param>
     /// <param name="pageSize">The maximum number of posts to return per page.</param>
+    /// <param name="tags">The tags of the posts to return.</param>
     /// <returns>A collection of blog posts.</returns>
-    IReadOnlyList<IBlogPost> GetBlogPosts(int page, int pageSize = 10);
+    IReadOnlyList<IBlogPost> GetBlogPosts(int page, int pageSize = 10, string[]? tags = null);
+
+    /// <summary>
+    ///     Returns the number of legacy comments for the specified post.
+    /// </summary>
+    /// <param name="post">The post whose legacy comments to count.</param>
+    /// <returns>The total number of legacy comments.</returns>
+    int GetLegacyCommentCount(IBlogPost post);
+
+    /// <summary>
+    ///     Returns the collection of legacy comments for the specified post.
+    /// </summary>
+    /// <param name="post">The post whose legacy comments to retrieve.</param>
+    /// <returns>A read-only view of the legacy comments.</returns>
+    IReadOnlyList<ILegacyComment> GetLegacyComments(IBlogPost post);
+
+    /// <summary>
+    ///     Returns the collection of replies to the specified legacy comment.
+    /// </summary>
+    /// <param name="comment">The comment whose replies to retrieve.</param>
+    /// <returns>A read-only view of the replies.</returns>
+    IReadOnlyList<ILegacyComment> GetLegacyReplies(ILegacyComment comment);
 
     /// <summary>
     ///     Returns the next blog post from the specified blog post.
@@ -41,6 +66,16 @@ public interface IBlogPostService
     /// <returns>The next blog post from the specified blog post.</returns>
     IBlogPost? GetNextPost(IBlogPost blogPost);
 
+    /// <summary>
+    ///     Returns the number of pages needed to render all blog posts, using the specified <paramref name="pageSize" /> as an
+    ///     indicator of how many posts are allowed per page.
+    /// </summary>
+    /// <param name="pageSize">The page size. Defaults to 10.</param>
+    /// <param name="visibility">The post visibility filter.</param>
+    /// <param name="tags">The tags of the posts to return.</param>
+    /// <returns>The page count.</returns>
+    int GetPageCount(int pageSize = 10, Visibility visibility = Visibility.None, string[]? tags = null);
+
     /// <summary>
     ///     Returns the previous blog post from the specified blog post.
     /// </summary>

OliverBooth.Common/Services/IBlogUserService.cs

@@ -1,7 +1,7 @@
 using System.Diagnostics.CodeAnalysis;
-using OliverBooth.Data.Blog;
+using OliverBooth.Common.Data.Blog;
 
-namespace OliverBooth.Services;
+namespace OliverBooth.Common.Services;
 
 /// <summary>
 ///     Represents a service for managing users.

OliverBooth.Common/Services/ICodeSnippetService.cs

@@ -0,0 +1,32 @@
+using System.Diagnostics.CodeAnalysis;
+using OliverBooth.Common.Data.Web;
+
+namespace OliverBooth.Common.Services;
+
+/// <summary>
+///     Represents a service which can fetch multi-language code snippets.
+/// </summary>
+public interface ICodeSnippetService
+{
+    /// <summary>
+    ///     Returns all the languages which apply to the specified snippet.
+    /// </summary>
+    /// <param name="id">The ID of the snippet whose languages should be returned.</param>
+    /// <returns>
+    ///     A read-only view of the languages that apply to the snippet. This list may be empty if the snippet ID is invalid.
+    /// </returns>
+    IReadOnlyList<string> GetLanguagesForSnippet(int id);
+
+    /// <summary>
+    ///     Attempts to find a code snippet by the specified ID, in the specified language.
+    /// </summary>
+    /// <param name="id">The ID of the snippet to search for.</param>
+    /// <param name="language">The language to search for.</param>
+    /// <param name="snippet">
+    ///     When this method returns, contains the code snippet matching the specified criteria, if such a snippet was found;
+    ///     otherwise, <see langword="null" />.
+    /// </param>
+    /// <returns><see langword="true" /> if the snippet was found; otherwise, <see langword="false" />.</returns>
+    /// <exception cref="ArgumentNullException"><paramref name="language" /> is <see langword="null" />.</exception>
+    bool TryGetCodeSnippetForLanguage(int id, string language, [NotNullWhen(true)] out ICodeSnippet? snippet);
+}

OliverBooth.Common/Services/IContactService.cs

@@ -1,6 +1,6 @@
-using OliverBooth.Data.Web;
+using OliverBooth.Common.Data.Web;
 
-namespace OliverBooth.Services;
+namespace OliverBooth.Common.Services;
 
 /// <summary>
 ///     Represents a service for managing contact information.

OliverBooth.Common/Services/IMastodonService.cs

@@ -1,6 +1,6 @@
-using OliverBooth.Data.Mastodon;
+using OliverBooth.Common.Data.Mastodon;
 
-namespace OliverBooth.Services;
+namespace OliverBooth.Common.Services;
 
 public interface IMastodonService
 {
@@ -8,5 +8,5 @@ public interface IMastodonService
     ///     Gets the latest status posted to Mastodon.
     /// </summary>
     /// <returns>The latest status.</returns>
-    MastodonStatus GetLatestStatus();
+    IMastodonStatus GetLatestStatus();
 }

OliverBooth.Common/Services/IProgrammingLanguageService.cs

@@ -0,0 +1,14 @@
+namespace OliverBooth.Common.Services;
+
+/// <summary>
+///     Represents a service which can perform programming language lookup.
+/// </summary>
+public interface IProgrammingLanguageService
+{
+    /// <summary>
+    ///     Returns the human-readable name of a language.
+    /// </summary>
+    /// <param name="alias">The alias of the language.</param>
+    /// <returns>The human-readable name, or <paramref name="alias" /> if the name could not be found.</returns>
+    string GetLanguageName(string alias);
+}

OliverBooth.Common/Services/IProjectService.cs

@@ -1,7 +1,7 @@
 using System.Diagnostics.CodeAnalysis;
-using OliverBooth.Data.Web;
+using OliverBooth.Common.Data.Web;
 
-namespace OliverBooth.Services;
+namespace OliverBooth.Common.Services;
 
 /// <summary>
 ///     Represents a service for interacting with projects.

OliverBooth.Common/Services/IReadingListService.cs

@@ -1,6 +1,6 @@
-using OliverBooth.Data.Web;
+using OliverBooth.Common.Data.Web;
 
-namespace OliverBooth.Services;
+namespace OliverBooth.Common.Services;
 
 /// <summary>
 ///     Represents a service which fetches books from the reading list.

OliverBooth.Common/Services/ITutorialService.cs

@@ -0,0 +1,124 @@
+using System.Diagnostics.CodeAnalysis;
+using OliverBooth.Common.Data;
+using OliverBooth.Common.Data.Blog;
+using OliverBooth.Common.Data.Web;
+
+namespace OliverBooth.Common.Services;
+
+/// <summary>
+///     Represents a service which can retrieve tutorial articles.
+/// </summary>
+public interface ITutorialService
+{
+    /// <summary>
+    ///     Gets the articles within a tutorial folder.
+    /// </summary>
+    /// <param name="folder">The folder whose articles to retrieve.</param>
+    /// <param name="visibility">The visibility to filter by. -1 does not filter.</param>
+    /// <returns>A read-only view of the articles in the folder.</returns>
+    IReadOnlyCollection<ITutorialArticle> GetArticles(ITutorialFolder folder, Visibility visibility = Visibility.None);
+
+    /// <summary>
+    ///     Gets the tutorial folders within a specified folder.
+    /// </summary>
+    /// <param name="parent">The parent folder.</param>
+    /// <param name="visibility">The visibility to filter by. -1 does not filter.</param>
+    /// <returns>A read-only view of the subfolders in the folder.</returns>
+    IReadOnlyCollection<ITutorialFolder> GetFolders(ITutorialFolder? parent = null, Visibility visibility = Visibility.None);
+
+    /// <summary>
+    ///     Gets a folder by its ID.
+    /// </summary>
+    /// <param name="id">The ID of the folder to get</param>
+    /// <param name="folder">
+    ///     When this method returns, contains the folder whose ID is equal to the ID specified, or
+    ///     <see langword="null" /> if no such folder was found.
+    /// </param>
+    /// <returns><see langword="true" /></returns> 
+    ITutorialFolder? GetFolder(int id);
+
+    /// <summary>
+    ///     Gets a folder by its slug.
+    /// </summary>
+    /// <param name="slug">The slug of the folder.</param>
+    /// <param name="parent">The parent folder.</param>
+    /// <returns>The folder.</returns>
+    ITutorialFolder? GetFolder(string? slug, ITutorialFolder? parent = null);
+
+    /// <summary>
+    ///     Gets the full slug of the specified folder.
+    /// </summary>
+    /// <param name="folder">The folder whose slug to return.</param>
+    /// <returns>The full slug of the folder.</returns>
+    /// <exception cref="ArgumentNullException"><paramref name="folder" /> is <see langword="null" />.</exception>
+    string GetFullSlug(ITutorialFolder folder);
+
+    /// <summary>
+    ///     Gets the full slug of the specified article.
+    /// </summary>
+    /// <param name="article">The article whose slug to return.</param>
+    /// <returns>The full slug of the article.</returns>
+    /// <exception cref="ArgumentNullException"><paramref name="article" /> is <see langword="null" />.</exception>
+    string GetFullSlug(ITutorialArticle article);
+
+    /// <summary>
+    ///     Returns the number of legacy comments for the specified article.
+    /// </summary>
+    /// <param name="article">The article whose legacy comments to count.</param>
+    /// <returns>The total number of legacy comments.</returns>
+    int GetLegacyCommentCount(ITutorialArticle article);
+
+    /// <summary>
+    ///     Returns the collection of legacy comments for the specified article.
+    /// </summary>
+    /// <param name="article">The article whose legacy comments to retrieve.</param>
+    /// <returns>A read-only view of the legacy comments.</returns>
+    IReadOnlyList<ILegacyComment> GetLegacyComments(ITutorialArticle article);
+
+    /// <summary>
+    ///     Returns the collection of replies to the specified legacy comment.
+    /// </summary>
+    /// <param name="comment">The comment whose replies to retrieve.</param>
+    /// <returns>A read-only view of the replies.</returns>
+    IReadOnlyList<ILegacyComment> GetLegacyReplies(ILegacyComment comment);
+
+    /// <summary>
+    ///     Renders the body of the specified article.
+    /// </summary>
+    /// <param name="article">The article to render.</param>
+    /// <returns>The rendered HTML of the article.</returns>
+    string RenderArticle(ITutorialArticle article);
+
+    /// <summary>
+    ///     Renders the excerpt of the specified article.
+    /// </summary>
+    /// <param name="article">The article whose excerpt to render.</param>
+    /// <param name="wasTrimmed">
+    ///     When this method returns, contains <see langword="true" /> if the excerpt was trimmed; otherwise,
+    ///     <see langword="false" />.
+    /// </param>
+    /// <returns>The rendered HTML of the article's excerpt.</returns>
+    string RenderExcerpt(ITutorialArticle article, out bool wasTrimmed);
+
+    /// <summary>
+    ///     Attempts to find an article by its ID.
+    /// </summary>
+    /// <param name="id">The ID of the article.</param>
+    /// <param name="article">
+    ///     When this method returns, contains the article whose ID matches the specified <paramref name="id" />, or
+    ///     <see langword="null" /> if no such article was found.
+    /// </param>
+    /// <returns><see langword="true" /> if a matching article was found; otherwise, <see langword="false" />.</returns>
+    bool TryGetArticle(int id, [NotNullWhen(true)] out ITutorialArticle? article);
+
+    /// <summary>
+    ///     Attempts to find an article by its slug.
+    /// </summary>
+    /// <param name="slug">The slug of the article.</param>
+    /// <param name="article">
+    ///     When this method returns, contains the article whose slug matches the specified <paramref name="slug" />, or
+    ///     <see langword="null" /> if no such article was found.
+    /// </param>
+    /// <returns><see langword="true" /> if a matching article was found; otherwise, <see langword="false" />.</returns>
+    bool TryGetArticle(string slug, [NotNullWhen(true)] out ITutorialArticle? article);
+}

OliverBooth.Extensions.Markdig/Markdown/Callout/CalloutBlock.cs

@@ -0,0 +1,43 @@
+using Markdig.Helpers;
+using Markdig.Syntax;
+
+namespace OliverBooth.Extensions.Markdig.Markdown.Callout;
+
+/// <summary>
+///     Represents a callout block.
+/// </summary>
+internal sealed class CalloutBlock : QuoteBlock
+{
+    /// <summary>
+    ///     Initializes a new instance of the <see cref="CalloutBlock" /> class.
+    /// </summary>
+    /// <param name="type">The type of the callout.</param>
+    public CalloutBlock(StringSlice type) : base(null)
+    {
+        Type = type;
+    }
+
+    /// <summary>
+    ///     Gets or sets a value indicating whether this callout is foldable.
+    /// </summary>
+    /// <value><see langword="true" /> if this callout is foldable; otherwise, <see langword="false" />.</value>
+    public bool Foldable { get; set; }
+
+    /// <summary>
+    ///     Gets or sets the title of the callout.
+    /// </summary>
+    /// <value>The title of the callout.</value>
+    public StringSlice Title { get; set; }
+
+    /// <summary>
+    ///     Gets or sets the trailing whitespace trivia.
+    /// </summary>
+    /// <value>The trailing whitespace trivia.</value>
+    public StringSlice TrailingWhitespaceTrivia { get; set; }
+
+    /// <summary>
+    ///     Gets or sets the type of the callout.
+    /// </summary>
+    /// <value>The type of the callout.</value>
+    public StringSlice Type { get; set; }
+}

OliverBooth.Extensions.Markdig/Markdown/Callout/CalloutExtension.cs

@@ -0,0 +1,32 @@
+using Markdig;
+using Markdig.Parsers.Inlines;
+using Markdig.Renderers;
+using Markdig.Renderers.Html;
+
+namespace OliverBooth.Extensions.Markdig.Markdown.Callout;
+
+/// <summary>
+///     Extension for adding Obsidian-style callouts to a Markdown pipeline.
+/// </summary>
+internal sealed class CalloutExtension : IMarkdownExtension
+{
+    /// <inheritdoc />
+    public void Setup(MarkdownPipelineBuilder pipeline)
+    {
+        var parser = pipeline.InlineParsers.Find<CalloutInlineParser>();
+        if (parser is null)
+        {
+            pipeline.InlineParsers.InsertBefore<LinkInlineParser>(new CalloutInlineParser());
+        }
+    }
+
+    /// <inheritdoc />
+    public void Setup(MarkdownPipeline pipeline, IMarkdownRenderer renderer)
+    {
+        var blockRenderer = renderer.ObjectRenderers.FindExact<CalloutRenderer>();
+        if (blockRenderer is null)
+        {
+            renderer.ObjectRenderers.InsertBefore<QuoteBlockRenderer>(new CalloutRenderer(pipeline));
+        }
+    }
+}

OliverBooth.Extensions.Markdig/Markdown/Callout/CalloutInlineParser.cs

@@ -0,0 +1,176 @@
+using System.Reflection;
+using Cysharp.Text;
+using Markdig.Helpers;
+using Markdig.Parsers;
+using Markdig.Renderers.Html;
+using Markdig.Syntax;
+
+namespace OliverBooth.Extensions.Markdig.Markdown.Callout;
+
+/// <summary>
+///     An inline parser for Obsidian-style callouts (<c>[!NOTE]</c> etc.)
+/// </summary>
+internal sealed class CalloutInlineParser : InlineParser
+{
+    // ugly hack to access internal method
+    private static readonly MethodInfo ReplaceParentContainerMethod =
+        typeof(InlineProcessor).GetMethod("ReplaceParentContainer", BindingFlags.Instance | BindingFlags.NonPublic)!;
+
+    /// <summary>
+    ///     Initializes a new instance of the <see cref="CalloutInlineParser" /> class.
+    /// </summary>
+    public CalloutInlineParser()
+    {
+        OpeningCharacters = ['['];
+    }
+
+    /// <inheritdoc />
+    public override bool Match(InlineProcessor processor, ref StringSlice slice)
+    {
+        // We expect the alert to be the first child of a quote block. Example:
+        // > [!NOTE]
+        // > This is a note
+        if (processor.Block is not ParagraphBlock { Parent: QuoteBlock quoteBlock } paragraphBlock ||
+            paragraphBlock.Inline?.FirstChild != null)
+        {
+            return false;
+        }
+
+        StringSlice cache = slice;
+        char current = slice.NextChar();
+
+        if (current != '!')
+        {
+            slice = cache;
+            return false;
+        }
+
+        current = slice.NextChar(); // skip !
+
+        int start = slice.Start;
+        int end = start;
+
+        while (current.IsAlphaUpper())
+        {
+            end = slice.Start;
+            current = slice.NextChar();
+        }
+
+        if (current != ']' || start == end)
+        {
+            slice = cache;
+            return false;
+        }
+
+        var type = new StringSlice(slice.Text, start, end);
+        current = slice.NextChar(); // skip ]
+        start = slice.Start;
+
+        bool fold = false;
+        if (current == '-')
+        {
+            fold = true;
+            current = slice.NextChar(); // skip -
+            start = slice.Start;
+        }
+
+        ReadTitle(current, ref slice, out StringSlice title, out end);
+
+        var callout = new CalloutBlock(type)
+        {
+            Foldable = fold,
+            Span = quoteBlock.Span,
+            TrailingWhitespaceTrivia = new StringSlice(slice.Text, start, end),
+            Line = quoteBlock.Line,
+            Column = quoteBlock.Column,
+            Title = title
+        };
+
+        AddAttributes(callout, type);
+        ReplaceQuoteBlock(processor, quoteBlock, callout);
+        return true;
+    }
+
+    private static void ReadTitle(char startChar, ref StringSlice slice, out StringSlice title, out int end)
+    {
+        using Utf16ValueStringBuilder builder = ZString.CreateStringBuilder();
+
+        char current = startChar;
+        while (true)
+        {
+            if (current is not ('\0' or '\r' or '\n'))
+            {
+                builder.Append(current);
+                current = slice.NextChar();
+                continue;
+            }
+
+            end = slice.Start;
+            if (HandleCharacter(ref slice, ref end, ref current))
+            {
+                continue;
+            }
+
+            break;
+        }
+
+        title = new StringSlice(builder.ToString(), 0, builder.Length);
+    }
+
+    private static bool HandleCharacter(ref StringSlice slice, ref int end, ref char current)
+    {
+        switch (current)
+        {
+            case '\r':
+                current = slice.NextChar(); // skip \r
+
+                if (current is not ('\0' or '\n'))
+                {
+                    return true;
+                }
+
+                end = slice.Start;
+                if (current == '\n')
+                {
+                    slice.NextChar(); // skip \n
+                }
+
+                break;
+
+            case '\n':
+                slice.NextChar(); // skip \n
+                break;
+        }
+
+        return false;
+    }
+
+    private static void AddAttributes(IMarkdownObject callout, StringSlice type)
+    {
+        HtmlAttributes attributes = callout.GetAttributes();
+        attributes.AddClass("callout");
+        attributes.AddProperty("data-callout", type.AsSpan().ToString().ToLowerInvariant());
+    }
+
+    private static void ReplaceQuoteBlock(InlineProcessor processor, QuoteBlock quoteBlock, CalloutBlock callout)
+    {
+        ContainerBlock? parentQuoteBlock = quoteBlock.Parent;
+        if (parentQuoteBlock is null)
+        {
+            return;
+        }
+
+        int indexOfQuoteBlock = parentQuoteBlock.IndexOf(quoteBlock);
+        parentQuoteBlock[indexOfQuoteBlock] = callout;
+
+        while (quoteBlock.Count > 0)
+        {
+            var block = quoteBlock[0];
+            quoteBlock.RemoveAt(0);
+            callout.Add(block);
+        }
+
+        ReplaceParentContainerMethod.Invoke(processor, [quoteBlock, callout]);
+        // ReplaceParentContainer(processor, quoteBlock, callout);
+    }
+}

OliverBooth.Extensions.Markdig/Markdown/Callout/CalloutRenderer.cs

@@ -0,0 +1,119 @@
+using HtmlAgilityPack;
+using Humanizer;
+using Markdig;
+using Markdig.Renderers;
+using Markdig.Renderers.Html;
+
+namespace OliverBooth.Extensions.Markdig.Markdown.Callout;
+
+/// <summary>
+///     Represents an HTML renderer which renders a <see cref="CalloutBlock" />.
+/// </summary>
+internal sealed class CalloutRenderer : HtmlObjectRenderer<CalloutBlock>
+{
+    private readonly MarkdownPipeline _pipeline;
+
+    private static readonly Dictionary<string, string> CalloutTypes = new()
+    {
+        ["NOTE"] = "pencil",
+        ["ABSTRACT"] = "clipboard-list",
+        ["INFO"] = "info",
+        ["TODO"] = "circle-check",
+        ["TIP"] = "flame",
+        ["IMPORTANT"] = "flame",
+        ["SUCCESS"] = "check",
+        ["QUESTION"] = "circle-help",
+        ["WARNING"] = "triangle-alert",
+        ["FAILURE"] = "x",
+        ["DANGER"] = "zap",
+        ["BUG"] = "bug",
+        ["EXAMPLE"] = "list",
+        ["CITE"] = "quote",
+        ["UPDATE"] = "calendar-check",
+    };
+
+    public CalloutRenderer(MarkdownPipeline pipeline)
+    {
+        _pipeline = pipeline;
+    }
+
+    /// <inheritdoc />
+    protected override void Write(HtmlRenderer renderer, CalloutBlock block)
+    {
+        renderer.EnsureLine();
+        if (renderer.EnableHtmlForBlock)
+        {
+            RenderAsHtml(renderer, block, _pipeline);
+        }
+        else
+        {
+            RenderAsText(renderer, block);
+        }
+
+        renderer.EnsureLine();
+    }
+
+    private static void RenderAsHtml(HtmlRenderer renderer, CalloutBlock block, MarkdownPipeline pipeline)
+    {
+        string title = block.Title.Text;
+        ReadOnlySpan<char> type = block.Type.AsSpan();
+        Span<char> upperType = stackalloc char[type.Length];
+        type.ToUpperInvariant(upperType);
+
+        if (!CalloutTypes.TryGetValue(upperType.ToString(), out string? lucideClass))
+        {
+            lucideClass = "pencil";
+        }
+
+        var typeString = type.ToString().ToLowerInvariant();
+
+        renderer.Write($"<div class=\"callout\" data-callout=\"{typeString}\"");
+        if (block.Foldable)
+        {
+            renderer.Write(" data-callout-fold=\"true\"");
+        }
+
+        renderer.Write('>');
+        renderer.Write("<div class=\"callout-title\"><i data-lucide=\"");
+        renderer.Write(lucideClass);
+        renderer.Write("\"></i> ");
+
+        string calloutTitle = title.Length == 0 ? typeString.Humanize(LetterCasing.Sentence) : title;
+        WriteTitle(renderer, pipeline, calloutTitle);
+
+        if (block.Foldable)
+        {
+            renderer.Write("<span class=\"callout-fold\"><i data-lucide=\"chevron-down\"></i></span>");
+        }
+
+        renderer.WriteLine("</div>");
+        renderer.Write("<div class=\"callout-content\">");
+        renderer.WriteChildren(block);
+        renderer.WriteLine("</div>");
+        renderer.WriteLine("</div>");
+        renderer.EnsureLine();
+    }
+
+    private static void WriteTitle(TextRendererBase renderer, MarkdownPipeline pipeline, string calloutTitle)
+    {
+        string html = global::Markdig.Markdown.ToHtml(calloutTitle, pipeline);
+        var document = new HtmlDocument();
+        document.LoadHtml(html);
+        if (document.DocumentNode.FirstChild is { Name: "p" } child)
+        {
+            // ugly hack to remove <p> tag generated by Markdig
+            document.DocumentNode.InnerHtml = child.InnerHtml;
+        }
+
+        document.Save(renderer.Writer);
+    }
+
+    private static void RenderAsText(HtmlRenderer renderer, CalloutBlock block)
+    {
+        string title = block.Title.Text;
+        ReadOnlySpan<char> type = block.Type.AsSpan();
+        renderer.WriteLine(title.Length == 0 ? type.ToString().ToUpperInvariant() : title.ToUpperInvariant());
+        renderer.WriteChildren(block);
+        renderer.EnsureLine();
+    }
+}

OliverBooth.Extensions.Markdig/Markdown/Template/TemplateExtension.cs

@@ -1,8 +1,8 @@
 using Markdig;
 using Markdig.Renderers;
-using OliverBooth.Services;
+using OliverBooth.Extensions.Markdig.Services;
 
-namespace OliverBooth.Markdown.Template;
+namespace OliverBooth.Extensions.Markdig.Markdown.Template;
 
 /// <summary>
 ///     Represents a Markdown extension that adds support for MediaWiki-style templates.

OliverBooth.Extensions.Markdig/Markdown/Template/TemplateInline.cs

@@ -1,6 +1,6 @@
 using Markdig.Syntax.Inlines;
 
-namespace OliverBooth.Markdown.Template;
+namespace OliverBooth.Extensions.Markdig.Markdown.Template;
 
 /// <summary>
 ///     Represents a Markdown inline element that represents a MediaWiki-style template.

OliverBooth.Extensions.Markdig/Markdown/Template/TemplateInlineParser.cs

@@ -2,7 +2,7 @@ using Cysharp.Text;
 using Markdig.Helpers;
 using Markdig.Parsers;
 
-namespace OliverBooth.Markdown.Template;
+namespace OliverBooth.Extensions.Markdig.Markdown.Template;
 
 /// <summary>
 ///     Represents a Markdown inline parser that handles MediaWiki-style templates.

OliverBooth.Extensions.Markdig/Markdown/Template/TemplateRenderer.cs

@@ -1,8 +1,8 @@
 using Markdig.Renderers;
 using Markdig.Renderers.Html;
-using OliverBooth.Services;
+using OliverBooth.Extensions.Markdig.Services;
 
-namespace OliverBooth.Markdown.Template;
+namespace OliverBooth.Extensions.Markdig.Markdown.Template;
 
 /// <summary>
 ///     Represents a Markdown object renderer that handles <see cref="TemplateInline" /> elements.

OliverBooth.Extensions.Markdig/Markdown/Timestamp/TimestampExtension.cs

@@ -1,7 +1,7 @@
 using Markdig;
 using Markdig.Renderers;
 
-namespace OliverBooth.Markdown.Timestamp;
+namespace OliverBooth.Extensions.Markdig.Markdown.Timestamp;
 
 /// <summary>
 ///     Represents a Markdig extension that supports Discord-style timestamps.

OliverBooth.Extensions.Markdig/Markdown/Timestamp/TimestampFormat.cs

@@ -1,4 +1,4 @@
-namespace OliverBooth.Markdown.Timestamp;
+namespace OliverBooth.Extensions.Markdig.Markdown.Timestamp;
 
 /// <summary>
 ///     An enumeration of timestamp formats.

OliverBooth.Extensions.Markdig/Markdown/Timestamp/TimestampInline.cs

@@ -1,6 +1,6 @@
 using Markdig.Syntax.Inlines;
 
-namespace OliverBooth.Markdown.Timestamp;
+namespace OliverBooth.Extensions.Markdig.Markdown.Timestamp;
 
 /// <summary>
 ///     Represents a Markdown inline element that contains a timestamp.

OliverBooth.Extensions.Markdig/Markdown/Timestamp/TimestampInlineParser.cs

@@ -1,7 +1,7 @@
 using Markdig.Helpers;
 using Markdig.Parsers;
 
-namespace OliverBooth.Markdown.Timestamp;
+namespace OliverBooth.Extensions.Markdig.Markdown.Timestamp;
 
 /// <summary>
 ///     Represents a Markdown inline parser that matches Discord-style timestamps.

OliverBooth.Extensions.Markdig/Markdown/Timestamp/TimestampRenderer.cs

@@ -3,7 +3,7 @@ using Humanizer;
 using Markdig.Renderers;
 using Markdig.Renderers.Html;
 
-namespace OliverBooth.Markdown.Timestamp;
+namespace OliverBooth.Extensions.Markdig.Markdown.Timestamp;
 
 /// <summary>
 ///     Represents a Markdown object renderer that renders <see cref="TimestampInline" /> elements.

OliverBooth.Extensions.Markdig/MarkdownPipelineExtensions.cs

@@ -0,0 +1,56 @@
+using Markdig;
+using OliverBooth.Extensions.Markdig.Markdown.Callout;
+using OliverBooth.Extensions.Markdig.Markdown.Template;
+using OliverBooth.Extensions.Markdig.Services;
+
+namespace OliverBooth.Extensions.Markdig;
+
+/// <summary>
+///     Extension methods for <see cref="MarkdownPipelineBuilder" />.
+/// </summary>
+public static class MarkdownPipelineExtensions
+{
+    /// <summary>
+    ///     Enables the use of Obsidian-style callouts in this pipeline.
+    /// </summary>
+    /// <param name="builder">The Markdig markdown pipeline builder.</param>
+    /// <returns>The modified Markdig markdown pipeline builder.</returns>
+    /// <exception cref="ArgumentNullException"><paramref name="builder" /> is <see langword="null" />.</exception>
+    public static MarkdownPipelineBuilder UseCallouts(this MarkdownPipelineBuilder builder)
+    {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        builder.Extensions.AddIfNotAlready<CalloutExtension>();
+        return builder;
+    }
+
+    /// <summary>
+    ///     Enables the use of Wiki-style templates in this pipeline.
+    /// </summary>
+    /// <param name="builder">The Markdig markdown pipeline builder.</param>
+    /// <param name="templateService">The template service responsible for fetching and rendering templates.</param>
+    /// <returns>The modified Markdig markdown pipeline builder.</returns>
+    /// <exception cref="ArgumentNullException">
+    ///     <para><paramref name="builder" /> is <see langword="null" />.</para>
+    ///     -or-
+    ///     <para><paramref name="templateService" /> is <see langword="null" />.</para>
+    /// </exception>
+    public static MarkdownPipelineBuilder UseTemplates(this MarkdownPipelineBuilder builder, ITemplateService templateService)
+    {
+        if (builder is null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        if (templateService is null)
+        {
+            throw new ArgumentNullException(nameof(templateService));
+        }
+
+        builder.Use(new TemplateExtension(templateService));
+        return builder;
+    }
+}

OliverBooth.Extensions.Markdig/OliverBooth.Extensions.Markdig.csproj

@@ -0,0 +1,17 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFramework>net8.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+    <ItemGroup>
+        <PackageReference Include="Markdig" Version="0.36.2"/>
+    </ItemGroup>
+
+    <ItemGroup>
+        <ProjectReference Include="..\OliverBooth.Common\OliverBooth.Common.csproj"/>
+    </ItemGroup>
+
+</Project>

OliverBooth.Extensions.Markdig/Services/ITemplateService.cs

@@ -1,8 +1,8 @@
 using System.Diagnostics.CodeAnalysis;
-using OliverBooth.Data.Web;
+using OliverBooth.Common.Data.Web;
-using OliverBooth.Markdown.Template;
+using OliverBooth.Extensions.Markdig.Markdown.Template;
 
-namespace OliverBooth.Services;
+namespace OliverBooth.Extensions.Markdig.Services;
 
 /// <summary>
 ///     Represents a service that renders MediaWiki-style templates.

OliverBooth.Extensions.SmartFormat/DateFormatter.cs

@@ -1,7 +1,7 @@
 using System.Globalization;
 using SmartFormat.Core.Extensions;
 
-namespace OliverBooth.Formatting;
+namespace OliverBooth.Extensions.SmartFormat;
 
 /// <summary>
 ///     Represents a SmartFormat formatter that formats a date.

OliverBooth.Extensions.SmartFormat/MarkdownFormatter.cs

@@ -1,7 +1,8 @@
 using Markdig;
+using Microsoft.Extensions.DependencyInjection;
 using SmartFormat.Core.Extensions;
 
-namespace OliverBooth.Formatting;
+namespace OliverBooth.Extensions.SmartFormat;
 
 /// <summary>
 ///     Represents a SmartFormat formatter that formats markdown.

OliverBooth.Extensions.SmartFormat/OliverBooth.Extensions.SmartFormat.csproj

@@ -0,0 +1,19 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFramework>net8.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+    <ItemGroup>
+        <PackageReference Include="Markdig" Version="0.36.2"/>
+        <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="8.0.1"/>
+        <PackageReference Include="SmartFormat.NET" Version="3.3.2"/>
+    </ItemGroup>
+
+    <ItemGroup>
+        <ProjectReference Include="..\OliverBooth.Common\OliverBooth.Common.csproj"/>
+    </ItemGroup>
+
+</Project>

OliverBooth.sln

@@ -13,6 +13,12 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution
 		global.json = global.json
 	EndProjectSection
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "OliverBooth.Extensions.Markdig", "OliverBooth.Extensions.Markdig\OliverBooth.Extensions.Markdig.csproj", "{3B012CD2-3201-41A0-BEF9-8E0B6247BB7E}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "OliverBooth.Common", "OliverBooth.Common\OliverBooth.Common.csproj", "{AD231E0F-FAED-4661-963F-EB22F858E148}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "OliverBooth.Extensions.SmartFormat", "OliverBooth.Extensions.SmartFormat\OliverBooth.Extensions.SmartFormat.csproj", "{9D56FA9B-B95B-460D-8745-41AABAA8BF61}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -23,6 +29,18 @@ Global
 		{A58A6FA3-480C-400B-822A-3786741BF39C}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{A58A6FA3-480C-400B-822A-3786741BF39C}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{A58A6FA3-480C-400B-822A-3786741BF39C}.Release|Any CPU.Build.0 = Release|Any CPU
+		{3B012CD2-3201-41A0-BEF9-8E0B6247BB7E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{3B012CD2-3201-41A0-BEF9-8E0B6247BB7E}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{3B012CD2-3201-41A0-BEF9-8E0B6247BB7E}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{3B012CD2-3201-41A0-BEF9-8E0B6247BB7E}.Release|Any CPU.Build.0 = Release|Any CPU
+		{AD231E0F-FAED-4661-963F-EB22F858E148}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{AD231E0F-FAED-4661-963F-EB22F858E148}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{AD231E0F-FAED-4661-963F-EB22F858E148}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{AD231E0F-FAED-4661-963F-EB22F858E148}.Release|Any CPU.Build.0 = Release|Any CPU
+		{9D56FA9B-B95B-460D-8745-41AABAA8BF61}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{9D56FA9B-B95B-460D-8745-41AABAA8BF61}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{9D56FA9B-B95B-460D-8745-41AABAA8BF61}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{9D56FA9B-B95B-460D-8745-41AABAA8BF61}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(NestedProjects) = preSolution
 	EndGlobalSection

OliverBooth/Controllers/Blog/BlogApiController.cs

@@ -1,102 +0,0 @@
-using Humanizer;
-using Microsoft.AspNetCore.Mvc;
-using OliverBooth.Data.Blog;
-using OliverBooth.Services;
-
-namespace OliverBooth.Controllers.Blog;
-
-/// <summary>
-///     Represents a controller for the blog API.
-/// </summary>
-[ApiController]
-[Route("api/blog")]
-[Produces("application/json")]
-public sealed class BlogApiController : ControllerBase
-{
-    private readonly IBlogPostService _blogPostService;
-    private readonly IBlogUserService _userService;
-
-    /// <summary>
-    ///     Initializes a new instance of the <see cref="BlogApiController" /> class.
-    /// </summary>
-    /// <param name="blogPostService">The <see cref="IBlogPostService" />.</param>
-    /// <param name="userService">The <see cref="IBlogUserService" />.</param>
-    public BlogApiController(IBlogPostService blogPostService, IBlogUserService userService)
-    {
-        _blogPostService = blogPostService;
-        _userService = userService;
-    }
-
-    [Route("count")]
-    public IActionResult Count()
-    {
-        return Ok(new { count = _blogPostService.GetBlogPostCount() });
-    }
-
-    [HttpGet("posts/{page:int?}")]
-    public IActionResult GetAllBlogPosts(int page = 0)
-    {
-        const int itemsPerPage = 10;
-        IReadOnlyList<IBlogPost> allPosts = _blogPostService.GetBlogPosts(page, itemsPerPage);
-        return Ok(allPosts.Select(post => CreatePostObject(post)));
-    }
-
-    [HttpGet("posts/tagged/{tag}/{page:int?}")]
-    public IActionResult GetTaggedBlogPosts(string tag, int page = 0)
-    {
-        const int itemsPerPage = 10;
-        tag = tag.Replace('-', ' ').ToLowerInvariant();
-
-        IReadOnlyList<IBlogPost> allPosts = _blogPostService.GetBlogPosts(page, itemsPerPage);
-        allPosts = allPosts.Where(post => post.Tags.Contains(tag)).ToList();
-        return Ok(allPosts.Select(post => CreatePostObject(post)));
-    }
-
-    [HttpGet("author/{id:guid}")]
-    public IActionResult GetAuthor(Guid id)
-    {
-        if (!_userService.TryGetUser(id, out IUser? author)) return NotFound();
-
-        return Ok(new
-        {
-            id = author.Id,
-            name = author.DisplayName,
-            avatarUrl = author.AvatarUrl,
-        });
-    }
-
-    [HttpGet("post/{id:guid?}")]
-    public IActionResult GetPost(Guid id)
-    {
-        if (!_blogPostService.TryGetPost(id, out IBlogPost? post)) return NotFound();
-        return Ok(CreatePostObject(post, true));
-    }
-
-    private object CreatePostObject(IBlogPost post, bool includeContent = false)
-    {
-        return new
-        {
-            id = post.Id,
-            commentsEnabled = post.EnableComments,
-            identifier = post.GetDisqusIdentifier(),
-            author = post.Author.Id,
-            title = post.Title,
-            published = post.Published.ToUnixTimeSeconds(),
-            updated = post.Updated?.ToUnixTimeSeconds(),
-            formattedPublishDate = post.Published.ToString("dddd, d MMMM yyyy HH:mm"),
-            formattedUpdateDate = post.Updated?.ToString("dddd, d MMMM yyyy HH:mm"),
-            humanizedTimestamp = post.Updated?.Humanize() ?? post.Published.Humanize(),
-            excerpt = _blogPostService.RenderExcerpt(post, out bool trimmed),
-            content = includeContent ? _blogPostService.RenderPost(post) : null,
-            trimmed,
-            tags = post.Tags.Select(t => t.Replace(' ', '-')),
-            url = new
-            {
-                year = post.Published.ToString("yyyy"),
-                month = post.Published.ToString("MM"),
-                day = post.Published.ToString("dd"),
-                slug = post.Slug
-            }
-        };
-    }
-}

OliverBooth/Controllers/Blog/RssController.cs

@@ -1,8 +1,8 @@
 using System.Xml.Serialization;
 using Microsoft.AspNetCore.Mvc;
-using OliverBooth.Data.Blog;
+using OliverBooth.Common.Data.Blog;
+using OliverBooth.Common.Services;
 using OliverBooth.Data.Blog.Rss;
-using OliverBooth.Services;
 
 namespace OliverBooth.Controllers.Blog;
 

OliverBooth/Controllers/ContactController.cs

@@ -11,6 +11,7 @@ public class ContactController : Controller
     private readonly ILogger<ContactController> _logger;
     private readonly IConfiguration _configuration;
     private readonly IConfigurationSection _destination;
+    private readonly IConfigurationSection _sender;
 
     /// <summary>
     ///     Initializes a new instance of the <see cref="ContactController" /> class.
@@ -21,7 +22,10 @@ public class ContactController : Controller
     {
         _logger = logger;
         _configuration = configuration;
-        _destination = configuration.GetSection("Mail").GetSection("Destination");
+
+        IConfigurationSection mailConfiguration = configuration.GetSection("Mail");
+        _destination = mailConfiguration.GetSection("Destination");
+        _sender = mailConfiguration.GetSection("Sender");
     }
 
     [HttpGet("{_?}")]
@@ -57,8 +61,9 @@ public class ContactController : Controller
         {
             await sender.WriteEmail
                 .To("Oliver Booth", _destination.Get<string>())
-                .From(name, email)
+                .From("Contact via Website", _sender.Get<string>())
-                .Subject($"[Contact via Website] {subject}")
+                .ReplyTo(name, email)
+                .Subject(subject)
                 .BodyText(message)
                 .SendAsync();
         }
@@ -79,8 +84,9 @@ public class ContactController : Controller
         string? mailServer = mailSection.GetSection("Server").Value;
         string? mailUsername = mailSection.GetSection("Username").Value;
         string? mailPassword = mailSection.GetSection("Password").Value;
+        ushort port = mailSection.GetSection("Port").Get<ushort>();
 
-        var sender = SmtpSender.Create(mailServer);
+        var sender = SmtpSender.Create(mailServer, port);
         sender.SetCredential(mailUsername, mailPassword);
         return sender;
     }

OliverBooth/Controllers/FormattedBlacklist.cs

@@ -1,7 +1,7 @@
 using System.Text;
 using Microsoft.AspNetCore.Mvc;
-using OliverBooth.Data.Web;
+using OliverBooth.Common.Data.Web;
-using OliverBooth.Services;
+using OliverBooth.Common.Services;
 
 namespace OliverBooth.Controllers;
 

OliverBooth/Data/Blog/BlogContext.cs

@@ -25,6 +25,12 @@ internal sealed class BlogContext : DbContext
     /// <value>The collection of blog posts.</value>
     public DbSet<BlogPost> BlogPosts { get; private set; } = null!;
 
+    /// <summary>
+    ///     Gets the collection of legacy comments in the database.
+    /// </summary>
+    /// <value>The collection of legacy comments.</value>
+    public DbSet<LegacyComment> LegacyComments { get; private set; } = null!;
+
     /// <summary>
     ///     Gets the collection of users in the database.
     /// </summary>
@@ -43,6 +49,7 @@ internal sealed class BlogContext : DbContext
     protected override void OnModelCreating(ModelBuilder modelBuilder)
     {
         modelBuilder.ApplyConfiguration(new BlogPostConfiguration());
+        modelBuilder.ApplyConfiguration(new LegacyCommentConfiguration());
         modelBuilder.ApplyConfiguration(new UserConfiguration());
     }
 }

OliverBooth/Data/Blog/BlogPost.cs

@@ -1,4 +1,6 @@
 using System.ComponentModel.DataAnnotations.Schema;
+using OliverBooth.Common.Data;
+using OliverBooth.Common.Data.Blog;
 using SmartFormat;
 
 namespace OliverBooth.Data.Blog;
@@ -16,6 +18,9 @@ internal sealed class BlogPost : IBlogPost
     /// <inheritdoc />
     public bool EnableComments { get; internal set; }
 
+    /// <inheritdoc />
+    public string? Excerpt { get; internal set; }
+
     /// <inheritdoc />
     public Guid Id { get; private set; } = Guid.NewGuid();
 
@@ -44,7 +49,7 @@ internal sealed class BlogPost : IBlogPost
     public DateTimeOffset? Updated { get; internal set; }
 
     /// <inheritdoc />
-    public BlogPostVisibility Visibility { get; internal set; }
+    public Visibility Visibility { get; internal set; }
 
     /// <inheritdoc />
     public int? WordPressId { get; set; }

OliverBooth/Data/Blog/Configuration/BlogPostConfiguration.cs

@@ -1,6 +1,7 @@
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Metadata.Builders;
 using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using OliverBooth.Common.Data;
 
 namespace OliverBooth.Data.Blog.Configuration;
 
@@ -20,13 +21,14 @@ internal sealed class BlogPostConfiguration : IEntityTypeConfiguration<BlogPost>
         builder.Property(e => e.Updated).IsRequired(false);
         builder.Property(e => e.Title).HasMaxLength(255).IsRequired();
         builder.Property(e => e.Body).IsRequired();
+        builder.Property(e => e.Excerpt).HasMaxLength(512).IsRequired(false);
         builder.Property(e => e.IsRedirect).IsRequired();
         builder.Property(e => e.RedirectUrl).HasConversion<UriToStringConverter>().HasMaxLength(255).IsRequired(false);
         builder.Property(e => e.EnableComments).IsRequired();
         builder.Property(e => e.DisqusDomain).IsRequired(false);
         builder.Property(e => e.DisqusIdentifier).IsRequired(false);
         builder.Property(e => e.DisqusPath).IsRequired(false);
-        builder.Property(e => e.Visibility).HasConversion(new EnumToStringConverter<BlogPostVisibility>()).IsRequired();
+        builder.Property(e => e.Visibility).HasConversion(new EnumToStringConverter<Visibility>()).IsRequired();
         builder.Property(e => e.Password).HasMaxLength(255).IsRequired(false);
         builder.Property(e => e.Tags).IsRequired()
             .HasConversion(

OliverBooth/Data/Blog/Configuration/LegacyCommentConfiguration.cs

@@ -0,0 +1,21 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace OliverBooth.Data.Blog.Configuration;
+
+internal sealed class LegacyCommentConfiguration : IEntityTypeConfiguration<LegacyComment>
+{
+    /// <inheritdoc />
+    public void Configure(EntityTypeBuilder<LegacyComment> builder)
+    {
+        builder.ToTable("LegacyComment");
+        builder.HasKey(e => e.Id);
+
+        builder.Property(e => e.Id).IsRequired();
+        builder.Property(e => e.PostId).IsRequired();
+        builder.Property(e => e.Author).IsRequired().HasMaxLength(50);
+        builder.Property(e => e.Avatar).IsRequired(false).HasMaxLength(32767);
+        builder.Property(e => e.Body).IsRequired().HasMaxLength(32767);
+        builder.Property(e => e.ParentComment).IsRequired(false);
+    }
+}

OliverBooth/Data/Blog/LegacyComment.cs

@@ -0,0 +1,34 @@
+using System.Web;
+using OliverBooth.Common.Data.Blog;
+
+namespace OliverBooth.Data.Blog;
+
+internal sealed class LegacyComment : ILegacyComment
+{
+    /// <inheritdoc />
+    public string? Avatar { get; private set; }
+
+    /// <inheritdoc />
+    public string Author { get; private set; } = string.Empty;
+
+    /// <inheritdoc />
+    public string Body { get; private set; } = string.Empty;
+
+    /// <inheritdoc />
+    public DateTimeOffset CreatedAt { get; private set; }
+
+    /// <inheritdoc />
+    public Guid Id { get; private set; }
+
+    /// <inheritdoc />
+    public Guid? ParentComment { get; private set; }
+
+    /// <inheritdoc />
+    public Guid PostId { get; private set; }
+
+    /// <inheritdoc />
+    public string GetAvatarUrl()
+    {
+        return Avatar ?? $"https://ui-avatars.com/api/?name={HttpUtility.UrlEncode(Author)}";
+    }
+}

OliverBooth/Data/Blog/User.cs

@@ -2,6 +2,7 @@ using System.ComponentModel.DataAnnotations.Schema;
 using System.Security.Cryptography;
 using System.Text;
 using Cysharp.Text;
+using OliverBooth.Common.Data.Blog;
 
 namespace OliverBooth.Data.Blog;
 

OliverBooth/Data/Mastodon/MastodonStatus.cs

@@ -1,34 +1,24 @@
 using System.Text.Json.Serialization;
+using OliverBooth.Common.Data.Mastodon;
 
 namespace OliverBooth.Data.Mastodon;
 
-public sealed class MastodonStatus
+/// <inheritdoc />
+internal sealed class MastodonStatus : IMastodonStatus
 {
-    /// <summary>
+    /// <inheritdoc />
-    ///     Gets the content of the status.
-    /// </summary>
-    /// <value>The content.</value>
     [JsonPropertyName("content")]
     public string Content { get; set; } = string.Empty;
 
-    /// <summary>
+    /// <inheritdoc />
-    ///     Gets the date and time at which this status was posted.
-    /// </summary>
-    /// <value>The post timestamp.</value>
     [JsonPropertyName("created_at")]
     public DateTimeOffset CreatedAt { get; set; }
 
-    /// <summary>
+    /// <inheritdoc />
-    ///     Gets the media attachments for this status.
-    /// </summary>
-    /// <value>The media attachments.</value>
     [JsonPropertyName("media_attachments")]
     public IReadOnlyList<MediaAttachment> MediaAttachments { get; set; } = ArraySegment<MediaAttachment>.Empty;
 
-    /// <summary>
+    /// <inheritdoc />
-    ///     Gets the original URI of the status.
-    /// </summary>
-    /// <value>The original URI.</value>
     [JsonPropertyName("url")]
     public Uri OriginalUri { get; set; } = null!;
 }

OliverBooth/Data/Web/BlacklistEntry.cs

@@ -1,3 +1,5 @@
+using OliverBooth.Common.Data.Web;
+
 namespace OliverBooth.Data.Web;
 
 /// <inheritdoc cref="IBlacklistEntry"/>

OliverBooth/Data/Web/Book.cs

@@ -1,4 +1,5 @@
 using NetBarcode;
+using OliverBooth.Common.Data.Web;
 using SixLabors.ImageSharp;
 using SixLabors.ImageSharp.Formats.Png;
 using SixLabors.ImageSharp.Processing;

OliverBooth/Data/Web/CodeSnippet.cs

@@ -0,0 +1,16 @@
+using OliverBooth.Common.Data.Web;
+
+namespace OliverBooth.Data.Web;
+
+/// <inheritdoc />
+internal sealed class CodeSnippet : ICodeSnippet
+{
+    /// <inheritdoc />
+    public string Content { get; } = string.Empty;
+
+    /// <inheritdoc />
+    public int Id { get; }
+
+    /// <inheritdoc />
+    public string Language { get; } = string.Empty;
+}

OliverBooth/Data/Web/Configuration/BookConfiguration.cs

@@ -1,6 +1,7 @@
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Metadata.Builders;
 using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using OliverBooth.Common.Data.Web;
 
 namespace OliverBooth.Data.Web.Configuration;
 

OliverBooth/Data/Web/Configuration/CodeSnippetConfiguration.cs

@@ -0,0 +1,21 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace OliverBooth.Data.Web.Configuration;
+
+/// <summary>
+///     Represents the configuration for the <see cref="Book" /> entity.
+/// </summary>
+internal sealed class CodeSnippetConfiguration : IEntityTypeConfiguration<CodeSnippet>
+{
+    /// <inheritdoc />
+    public void Configure(EntityTypeBuilder<CodeSnippet> builder)
+    {
+        builder.ToTable("CodeSnippet");
+        builder.HasKey(e => new { e.Id, e.Language });
+
+        builder.Property(e => e.Id);
+        builder.Property(e => e.Language);
+        builder.Property(e => e.Content);
+    }
+}

OliverBooth/Data/Web/Configuration/ProjectConfiguration.cs

@@ -1,6 +1,7 @@
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Metadata.Builders;
 using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using OliverBooth.Common.Data.Web;
 
 namespace OliverBooth.Data.Web.Configuration;
 

OliverBooth/Data/Web/Configuration/TutorialArticleConfiguration.cs

@@ -0,0 +1,32 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using OliverBooth.Common.Data;
+
+namespace OliverBooth.Data.Web.Configuration;
+
+/// <summary>
+///     Represents the configuration for the <see cref="Template" /> entity.
+/// </summary>
+internal sealed class TutorialArticleConfiguration : IEntityTypeConfiguration<TutorialArticle>
+{
+    public void Configure(EntityTypeBuilder<TutorialArticle> builder)
+    {
+        builder.ToTable("TutorialArticle");
+        builder.HasKey(e => e.Id);
+
+        builder.Property(e => e.Id).IsRequired();
+        builder.Property(e => e.Folder).IsRequired();
+        builder.Property(e => e.Excerpt).HasMaxLength(512).IsRequired(false);
+        builder.Property(e => e.Published).IsRequired();
+        builder.Property(e => e.Updated);
+        builder.Property(e => e.Slug).IsRequired();
+        builder.Property(e => e.Title).IsRequired();
+        builder.Property(e => e.PreviewImageUrl).HasConversion<UriToStringConverter>();
+        builder.Property(e => e.NextPart);
+        builder.Property(e => e.PreviousPart);
+        builder.Property(e => e.RedirectFrom).IsRequired(false);
+        builder.Property(e => e.Visibility).HasConversion<EnumToStringConverter<Visibility>>();
+        builder.Property(e => e.EnableComments).IsRequired();
+    }
+}

OliverBooth/Data/Web/Configuration/TutorialFolderConfiguration.cs

@@ -0,0 +1,25 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using OliverBooth.Common.Data;
+
+namespace OliverBooth.Data.Web.Configuration;
+
+/// <summary>
+///     Represents the configuration for the <see cref="Template" /> entity.
+/// </summary>
+internal sealed class TutorialFolderConfiguration : IEntityTypeConfiguration<TutorialFolder>
+{
+    public void Configure(EntityTypeBuilder<TutorialFolder> builder)
+    {
+        builder.ToTable("TutorialFolder");
+        builder.HasKey(e => e.Id);
+
+        builder.Property(e => e.Id).IsRequired();
+        builder.Property(e => e.Parent);
+        builder.Property(e => e.Slug).HasMaxLength(50).IsRequired();
+        builder.Property(e => e.Title).HasMaxLength(255).IsRequired();
+        builder.Property(e => e.PreviewImageUrl).HasConversion<UriToStringConverter>();
+        builder.Property(e => e.Visibility).HasConversion<EnumToStringConverter<Visibility>>();
+    }
+}

OliverBooth/Data/Web/ProgrammingLanguage.cs

@@ -1,3 +1,5 @@
+using OliverBooth.Common.Data.Web;
+
 namespace OliverBooth.Data.Web;
 
 /// <inheritdoc cref="IProgrammingLanguage" />

OliverBooth/Data/Web/Project.cs

@@ -1,3 +1,5 @@
+using OliverBooth.Common.Data.Web;
+
 namespace OliverBooth.Data.Web;
 
 /// <summary>

OliverBooth/Data/Web/Template.cs

@@ -1,3 +1,5 @@
+using OliverBooth.Common.Data.Web;
+
 namespace OliverBooth.Data.Web;
 
 /// <summary>

OliverBooth/Data/Web/TutorialArticle.cs

@@ -0,0 +1,118 @@
+using System.ComponentModel.DataAnnotations.Schema;
+using OliverBooth.Common.Data;
+using OliverBooth.Common.Data.Web;
+
+namespace OliverBooth.Data.Web;
+
+/// <summary>
+///     Represents a tutorial article.
+/// </summary>
+internal sealed class TutorialArticle : IEquatable<TutorialArticle>, ITutorialArticle
+{
+    /// <inheritdoc />
+    public string Body { get; private set; } = string.Empty;
+
+    /// <inheritdoc />
+    public bool EnableComments { get; internal set; }
+
+    /// <inheritdoc />
+    public string? Excerpt { get; private set; }
+
+    /// <inheritdoc />
+    public int Folder { get; private set; }
+
+    /// <inheritdoc />
+    [NotMapped]
+    public bool HasOtherParts => NextPart is not null || PreviousPart is not null;
+
+    /// <inheritdoc />
+    public int Id { get; private set; }
+
+    /// <inheritdoc />
+    public int? NextPart { get; private set; }
+
+    /// <inheritdoc />
+    public Uri? PreviewImageUrl { get; private set; }
+
+    /// <inheritdoc />
+    public int? PreviousPart { get; private set; }
+
+    /// <inheritdoc />
+    public DateTimeOffset Published { get; private set; }
+
+    /// <inheritdoc />
+    public Guid? RedirectFrom { get; private set; }
+
+    /// <inheritdoc />
+    public string Slug { get; private set; } = string.Empty;
+
+    /// <inheritdoc />
+    public string Title { get; private set; } = string.Empty;
+
+    /// <inheritdoc />
+    public DateTimeOffset? Updated { get; private set; }
+
+    /// <inheritdoc />
+    public Visibility Visibility { get; private set; }
+
+    /// <summary>
+    ///     Returns a value indicating whether two instances of <see cref="TutorialArticle" /> are equal.
+    /// </summary>
+    /// <param name="left">The first instance of <see cref="TutorialArticle" /> to compare.</param>
+    /// <param name="right">The second instance of <see cref="TutorialArticle" /> to compare.</param>
+    /// <returns>
+    ///     <see langword="true" /> if <paramref name="left" /> and <paramref name="right" /> are equal; otherwise,
+    ///     <see langword="false" />.
+    /// </returns>
+    public static bool operator ==(TutorialArticle? left, TutorialArticle? right) => Equals(left, right);
+
+    /// <summary>
+    ///     Returns a value indicating whether two instances of <see cref="TutorialArticle" /> are not equal.
+    /// </summary>
+    /// <param name="left">The first instance of <see cref="TutorialArticle" /> to compare.</param>
+    /// <param name="right">The second instance of <see cref="TutorialArticle" /> to compare.</param>
+    /// <returns>
+    ///     <see langword="true" /> if <paramref name="left" /> and <paramref name="right" /> are not equal; otherwise,
+    ///     <see langword="false" />.
+    /// </returns>
+    public static bool operator !=(TutorialArticle? left, TutorialArticle? right) => !(left == right);
+
+    /// <summary>
+    ///     Returns a value indicating whether this instance of <see cref="TutorialArticle" /> is equal to another
+    ///     instance.
+    /// </summary>
+    /// <param name="other">An instance to compare with this instance.</param>
+    /// <returns>
+    ///     <see langword="true" /> if <paramref name="other" /> is equal to this instance; otherwise,
+    ///     <see langword="false" />.
+    /// </returns>
+    public bool Equals(TutorialArticle? other)
+    {
+        if (ReferenceEquals(null, other)) return false;
+        if (ReferenceEquals(this, other)) return true;
+        return Id.Equals(other.Id);
+    }
+
+    /// <summary>
+    ///     Returns a value indicating whether this instance is equal to a specified object.
+    /// </summary>
+    /// <param name="obj">An object to compare with this instance.</param>
+    /// <returns>
+    ///     <see langword="true" /> if <paramref name="obj" /> is an instance of <see cref="TutorialArticle" /> and
+    ///     equals the value of this instance; otherwise, <see langword="false" />.
+    /// </returns>
+    public override bool Equals(object? obj)
+    {
+        return ReferenceEquals(this, obj) || obj is TutorialArticle other && Equals(other);
+    }
+
+    /// <summary>
+    ///     Gets the hash code for this instance.
+    /// </summary>
+    /// <returns>The hash code.</returns>
+    public override int GetHashCode()
+    {
+        // ReSharper disable once NonReadonlyMemberInGetHashCode
+        return Id;
+    }
+}

OliverBooth/Data/Web/TutorialFolder.cs

@@ -0,0 +1,89 @@
+using OliverBooth.Common.Data;
+using OliverBooth.Common.Data.Web;
+
+namespace OliverBooth.Data.Web;
+
+/// <summary>
+///     Represents a folder for tutorial articles.
+/// </summary>
+internal sealed class TutorialFolder : IEquatable<TutorialFolder>, ITutorialFolder
+{
+    /// <inheritdoc />
+    public int Id { get; private set; }
+
+    /// <inheritdoc />
+    public int? Parent { get; private set; }
+
+    /// <inheritdoc />
+    public Uri? PreviewImageUrl { get; private set; }
+
+    /// <inheritdoc />
+    public string Slug { get; private set; } = string.Empty;
+
+    /// <inheritdoc />
+    public string Title { get; private set; } = string.Empty;
+
+    /// <inheritdoc />
+    public Visibility Visibility { get; private set; }
+
+    /// <summary>
+    ///     Returns a value indicating whether two instances of <see cref="TutorialFolder" /> are equal.
+    /// </summary>
+    /// <param name="left">The first instance of <see cref="TutorialFolder" /> to compare.</param>
+    /// <param name="right">The second instance of <see cref="TutorialFolder" /> to compare.</param>
+    /// <returns>
+    ///     <see langword="true" /> if <paramref name="left" /> and <paramref name="right" /> are equal; otherwise,
+    ///     <see langword="false" />.
+    /// </returns>
+    public static bool operator ==(TutorialFolder? left, TutorialFolder? right) => Equals(left, right);
+
+    /// <summary>
+    ///     Returns a value indicating whether two instances of <see cref="TutorialFolder" /> are not equal.
+    /// </summary>
+    /// <param name="left">The first instance of <see cref="TutorialFolder" /> to compare.</param>
+    /// <param name="right">The second instance of <see cref="TutorialFolder" /> to compare.</param>
+    /// <returns>
+    ///     <see langword="true" /> if <paramref name="left" /> and <paramref name="right" /> are not equal; otherwise,
+    ///     <see langword="false" />.
+    /// </returns>
+    public static bool operator !=(TutorialFolder? left, TutorialFolder? right) => !(left == right);
+
+    /// <summary>
+    ///     Returns a value indicating whether this instance of <see cref="TutorialFolder" /> is equal to another
+    ///     instance.
+    /// </summary>
+    /// <param name="other">An instance to compare with this instance.</param>
+    /// <returns>
+    ///     <see langword="true" /> if <paramref name="other" /> is equal to this instance; otherwise,
+    ///     <see langword="false" />.
+    /// </returns>
+    public bool Equals(TutorialFolder? other)
+    {
+        if (ReferenceEquals(null, other)) return false;
+        if (ReferenceEquals(this, other)) return true;
+        return Id.Equals(other.Id);
+    }
+
+    /// <summary>
+    ///     Returns a value indicating whether this instance is equal to a specified object.
+    /// </summary>
+    /// <param name="obj">An object to compare with this instance.</param>
+    /// <returns>
+    ///     <see langword="true" /> if <paramref name="obj" /> is an instance of <see cref="TutorialFolder" /> and
+    ///     equals the value of this instance; otherwise, <see langword="false" />.
+    /// </returns>
+    public override bool Equals(object? obj)
+    {
+        return ReferenceEquals(this, obj) || obj is TutorialFolder other && Equals(other);
+    }
+
+    /// <summary>
+    ///     Gets the hash code for this instance.
+    /// </summary>
+    /// <returns>The hash code.</returns>
+    public override int GetHashCode()
+    {
+        // ReSharper disable once NonReadonlyMemberInGetHashCode
+        return Id;
+    }
+}

OliverBooth/Data/Web/WebContext.cs

@@ -25,6 +25,12 @@ internal sealed class WebContext : DbContext
     /// <value>The collection of books.</value>
     public DbSet<Book> Books { get; private set; } = null!;
 
+    /// <summary>
+    ///     Gets the collection of code snippets in the database.
+    /// </summary>
+    /// <value>The collection of code snippets.</value>
+    public DbSet<CodeSnippet> CodeSnippets { get; private set; } = null!;
+
     /// <summary>
     ///     Gets the collection of blacklist entries in the database.
     /// </summary>
@@ -55,6 +61,18 @@ internal sealed class WebContext : DbContext
     /// <value>The collection of templates.</value>
     public DbSet<Template> Templates { get; private set; } = null!;
 
+    /// <summary>
+    ///     Gets the collection of tutorial articles in the database.
+    /// </summary>
+    /// <value>The collection of tutorial articles.</value>
+    public DbSet<TutorialArticle> TutorialArticles { get; private set; } = null!;
+
+    /// <summary>
+    ///     Gets the collection of tutorial folders in the database.
+    /// </summary>
+    /// <value>The collection of tutorial folders.</value>
+    public DbSet<TutorialFolder> TutorialFolders { get; private set; } = null!;
+
     /// <inheritdoc />
     protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
     {
@@ -68,9 +86,12 @@ internal sealed class WebContext : DbContext
     {
         modelBuilder.ApplyConfiguration(new BlacklistEntryConfiguration());
         modelBuilder.ApplyConfiguration(new BookConfiguration());
+        modelBuilder.ApplyConfiguration(new CodeSnippetConfiguration());
         modelBuilder.ApplyConfiguration(new ProgrammingLanguageConfiguration());
         modelBuilder.ApplyConfiguration(new ProjectConfiguration());
         modelBuilder.ApplyConfiguration(new TemplateConfiguration());
+        modelBuilder.ApplyConfiguration(new TutorialArticleConfiguration());
+        modelBuilder.ApplyConfiguration(new TutorialFolderConfiguration());
         modelBuilder.ApplyConfiguration(new SiteConfigurationConfiguration());
     }
 }

OliverBooth/Extensions/HtmlUtility.cs

@@ -0,0 +1,153 @@
+using System.Web;
+using Cysharp.Text;
+using OliverBooth.Common.Data.Blog;
+using OliverBooth.Common.Data.Web;
+using OliverBooth.Common.Services;
+
+namespace OliverBooth.Extensions;
+
+/// <summary>
+///     Provides helper methods for generating HTML tags 
+/// </summary>
+public static class HtmlUtility
+{
+    /// <summary>
+    ///     Creates <c>&lt;meta&gt;</c> embed tags by pulling data from the specified blog post.
+    /// </summary>
+    /// <param name="post">The blog post whose metadata should be retrieved.</param>
+    /// <param name="blogPostService">The <see cref="IBlogPostService" /> injected by the page.</param>
+    /// <returns>A string containing a collection of <c>&lt;meta&gt;</c> embed tags.</returns>
+    /// <exception cref="ArgumentNullException">
+    ///     <para><paramref name="post" /> is <see langword="null" />.</para>
+    ///     -or-
+    ///     <para><paramref name="blogPostService" /> is <see langword="null" />.</para>
+    /// </exception>
+    public static string CreateMetaTagsFromPost(IBlogPost post, IBlogPostService blogPostService)
+    {
+        if (post is null)
+        {
+            throw new ArgumentNullException(nameof(post));
+        }
+
+        if (blogPostService is null)
+        {
+            throw new ArgumentNullException(nameof(blogPostService));
+        }
+
+
+        string excerpt = blogPostService.RenderExcerpt(post, out _);
+        var tags = new Dictionary<string, string>
+        {
+            ["title"] = post.Title,
+            ["description"] = excerpt,
+            ["author"] = post.Author.DisplayName
+        };
+        return CreateMetaTags(tags);
+    }
+
+    /// <summary>
+    ///     Creates <c>&lt;meta&gt;</c> embed tags by pulling data from the specified article.
+    /// </summary>
+    /// <param name="article">The article whose metadata should be retrieved.</param>
+    /// <param name="tutorialService">The <see cref="ITutorialService" /> injected by the page.</param>
+    /// <returns>A string containing a collection of <c>&lt;meta&gt;</c> embed tags.</returns>
+    /// <exception cref="ArgumentNullException">
+    ///     <para><paramref name="article" /> is <see langword="null" />.</para>
+    ///     -or-
+    ///     <para><paramref name="tutorialService" /> is <see langword="null" />.</para>
+    /// </exception>
+    public static string CreateMetaTagsFromTutorialArticle(ITutorialArticle article, ITutorialService tutorialService)
+    {
+        if (article is null)
+        {
+            throw new ArgumentNullException(nameof(article));
+        }
+
+        if (tutorialService is null)
+        {
+            throw new ArgumentNullException(nameof(tutorialService));
+        }
+
+
+        string excerpt = tutorialService.RenderExcerpt(article, out _);
+        var tags = new Dictionary<string, string>
+        {
+            ["title"] = article.Title,
+            ["description"] = excerpt,
+            ["author"] = "Oliver Booth" // TODO add article author support?
+        };
+        return CreateMetaTags(tags);
+    }
+
+    /// <summary>
+    ///     Creates <c>&lt;meta&gt;</c> embed tags by pulling data from the specified dictionary.
+    /// </summary>
+    /// <param name="tags">
+    ///     A dictionary containing the tag values. This dictionary should be in the form:
+    ///
+    ///     <list type="table">
+    ///         <listheader>
+    ///             <term>Key</term>
+    ///             <description>Description</description>
+    ///         </listheader>
+    ///
+    ///         <item>
+    ///             <term>description</term>
+    ///             <description>
+    ///                 The value to apply to the <c>description</c>, <c>og:description</c>, and <c>twitter:description</c>, tags.
+    ///             </description>
+    ///         </item>
+    ///
+    ///         <item>
+    ///             <term>author</term>
+    ///             <description>The value to apply to the <c>og:site_name</c>, and <c>twitter:creator</c>, tags.</description>
+    ///         </item>
+    ///
+    ///         <item>
+    ///             <term>title</term>
+    ///             <description>
+    ///                 The value to apply to the <c>title</c>, <c>og:title</c>, and <c>twitter:title</c>, tags.
+    ///             </description>
+    ///         </item>
+    ///     </list>
+    ///
+    ///     Any other values contained with the dictionary are ignored.
+    /// </param>
+    /// <returns>A string containing a collection of <c>&lt;meta&gt;</c> embed tags.</returns>
+    /// <exception cref="ArgumentNullException"><paramref name="tags" /> is <see langword="null" />.</exception>
+    public static string CreateMetaTags(IReadOnlyDictionary<string, string> tags)
+    {
+        if (tags is null)
+        {
+            throw new ArgumentNullException(nameof(tags));
+        }
+
+        using Utf8ValueStringBuilder builder = ZString.CreateUtf8StringBuilder();
+        builder.AppendLine("""<meta property="og:type" content="article">""");
+
+        if (tags.TryGetValue("description", out string? description))
+        {
+            description = HttpUtility.HtmlEncode(description);
+            builder.AppendLine($"""<meta name="description" content="{description}">""");
+            builder.AppendLine($"""<meta property="og:description" content="{description}">""");
+            builder.AppendLine($"""<meta property="twitter:description" content="{description}">""");
+        }
+
+        if (tags.TryGetValue("author", out string? author))
+        {
+            author = HttpUtility.HtmlEncode(author);
+            builder.AppendLine($"""<meta property="og:site_name" content="{author}">""");
+            builder.AppendLine($"""<meta property="twitter:creator" content="{author}">""");
+        }
+
+        if (tags.TryGetValue("title", out string? title))
+        {
+            title = HttpUtility.HtmlEncode(title);
+            builder.AppendLine($"""<meta name="title" content="{title}">""");
+            builder.AppendLine($"""<meta property="og:title" content="{title}">""");
+            builder.AppendLine($"""<meta property="twitter:title" content="{title}">""");
+        }
+
+        return builder.ToString();
+    }
+}

OliverBooth/Markdown/Template/CodeSnippetTemplateRenderer.cs

@@ -0,0 +1,140 @@
+using System.Diagnostics;
+using System.Text;
+using Markdig;
+using OliverBooth.Common.Data.Web;
+using OliverBooth.Common.Services;
+using OliverBooth.Extensions.Markdig.Markdown.Template;
+
+namespace OliverBooth.Markdown.Template;
+
+/// <summary>
+///     Represents a custom template renderer which renders the <c>{{Snippet}}</c> template.
+/// </summary>
+internal sealed class CodeSnippetTemplateRenderer : CustomTemplateRenderer
+{
+    private readonly ICodeSnippetService _codeSnippetService;
+    private readonly Lazy<MarkdownPipeline> _markdownPipeline;
+    private readonly IProgrammingLanguageService _programmingLanguageService;
+
+    /// <summary>
+    ///     Initializes a new instance of the <see cref="CodeSnippetTemplateRenderer" /> class.
+    /// </summary>
+    /// <param name="serviceProvider">The service provider.</param>
+    public CodeSnippetTemplateRenderer(IServiceProvider serviceProvider) : base(serviceProvider)
+    {
+        // lazily evaluate to avoid circular dependency problem causing tremendous stack overflow 
+        _markdownPipeline = new Lazy<MarkdownPipeline>(serviceProvider.GetRequiredService<MarkdownPipeline>);
+        _codeSnippetService = serviceProvider.GetRequiredService<ICodeSnippetService>();
+        _programmingLanguageService = serviceProvider.GetRequiredService<IProgrammingLanguageService>();
+    }
+
+    /// <inheritdoc />
+    public override string Render(TemplateInline template)
+    {
+        Debug.Assert(template.Name == "Snippet");
+        Trace.Assert(template.Name == "Snippet");
+
+        IReadOnlyList<string> argumentList = template.ArgumentList;
+
+        if (argumentList.Count < 1)
+        {
+            return DefaultRender(template);
+        }
+
+        if (!int.TryParse(argumentList[0], out int snippetId))
+        {
+            return DefaultRender(template);
+        }
+
+        var identifier = Guid.NewGuid();
+        var snippets = new List<ICodeSnippet>();
+
+        IReadOnlyList<string> languages = argumentList.Count > 1
+            ? argumentList[1].Split(';')
+            : _codeSnippetService.GetLanguagesForSnippet(snippetId);
+
+        foreach (string language in languages)
+        {
+            if (_codeSnippetService.TryGetCodeSnippetForLanguage(snippetId, language, out ICodeSnippet? snippet))
+            {
+                snippets.Add(snippet);
+            }
+        }
+
+        if (snippets.Count == 1)
+        {
+            ICodeSnippet snippet = snippets[0];
+            return RenderHtml(snippet);
+        }
+
+        var builder = new StringBuilder();
+        builder.AppendLine($"""
+                            <ul class="nav nav-tabs mb-3" id="snp-{identifier:N}" data-identifier="{identifier:N}" role="tablist"
+                            style="margin-bottom: -0.5em !important;">
+                            """);
+
+        for (var index = 0; index < languages.Count; index++)
+        {
+            var language = languages[index];
+            string classList = "";
+            if (index == 0)
+            {
+                classList = " active";
+            }
+
+            builder.AppendLine("""<li class="nav-item" role="presentation">""");
+            builder.AppendLine($"""
+                                    <a
+                                      data-tab-init
+                                      class="nav-link{classList}"
+                                      id="snp-{snippetId}-{identifier:N}-{language}-l"
+                                      href="#"
+                                      role="tab"
+                                      data-tabs="snp-{snippetId}-{identifier:N}"
+                                      aria-controls="snp-{snippetId}-{identifier:N}-{language}"
+                                      aria-selected="true"
+                                      >{_programmingLanguageService.GetLanguageName(language)}</a
+                                    >
+                                """);
+            builder.AppendLine("</li>");
+        }
+
+        builder.AppendLine("</ul>");
+
+        builder.AppendLine($"""<div class="tab-content" id="snp-{snippetId}-{identifier:N}">""");
+
+        for (var index = 0; index < snippets.Count; index++)
+        {
+            string classList = "";
+            if (index == 0)
+            {
+                classList = " show active";
+            }
+
+            var snippet = snippets[index];
+            string html = RenderHtml(snippet);
+            builder.AppendLine($"""
+                                <div class="tab-pane fade{classList}" id="snp-{snippetId}-{identifier:N}-{snippet.Language}" data-identifier="{identifier:N}" role="tabpanel"
+                                aria-labelledby="snp-{snippetId}-{identifier:N}-{snippet.Language}">
+                                """);
+            builder.AppendLine(html);
+            builder.AppendLine("</div>");
+        }
+
+        builder.AppendLine("</div>");
+
+        return builder.ToString();
+    }
+
+    private string RenderHtml(ICodeSnippet snippet)
+    {
+        return Markdig.Markdown.ToHtml($"```{snippet.Language}\n{snippet.Content}\n```", _markdownPipeline.Value);
+    }
+
+    private static string DefaultRender(TemplateInline template)
+    {
+        return template.ArgumentList.Count == 0
+            ? $"{{{{{template.Name}}}}}"
+            : $"{{{{{template.Name}|{string.Join('|', template.ArgumentList)}}}}}";
+    }
+}

OliverBooth/Markdown/Template/CustomTemplateRenderer.cs

@@ -0,0 +1,33 @@
+using Microsoft.EntityFrameworkCore;
+using OliverBooth.Data.Web;
+using OliverBooth.Extensions.Markdig.Markdown.Template;
+
+namespace OliverBooth.Markdown.Template;
+
+/// <summary>
+///     Represents a custom renderer which overrides the default behaviour of the template engine.
+/// </summary>
+internal abstract class CustomTemplateRenderer
+{
+    /// <summary>
+    ///     Initializes a new instance of the <see cref="CustomTemplateRenderer" /> class.
+    /// </summary>
+    /// <param name="serviceProvider">The service provider.</param>
+    protected CustomTemplateRenderer(IServiceProvider serviceProvider)
+    {
+        DbContextFactory = serviceProvider.GetRequiredService<IDbContextFactory<WebContext>>();
+    }
+
+    /// <summary>
+    ///     Gets the <see cref="WebContext" /> factory that was injected into this instance.
+    /// </summary>
+    /// <value>An <see cref="IDbContextFactory{TContext}" /> for <see cref="WebContext" />.</value>
+    protected IDbContextFactory<WebContext> DbContextFactory { get; }
+
+    /// <summary>
+    ///     Renders the specified template.
+    /// </summary>
+    /// <param name="template">The template to render.</param>
+    /// <returns>The rendered result of the template.</returns>
+    public abstract string Render(TemplateInline template);
+}

OliverBooth/OliverBooth.csproj

@@ -30,13 +30,9 @@
         <PackageReference Include="Alexinea.Extensions.Configuration.Toml" Version="7.0.0"/>
         <PackageReference Include="AspNetCore.ReCaptcha" Version="1.8.1"/>
         <PackageReference Include="BCrypt.Net-Core" Version="1.6.0"/>
-        <PackageReference Include="HtmlAgilityPack" Version="1.11.59"/>
-        <PackageReference Include="Humanizer.Core" Version="2.14.1"/>
         <PackageReference Include="MailKit" Version="4.4.0"/>
         <PackageReference Include="MailKitSimplified.Sender" Version="2.9.0"/>
-        <PackageReference Include="Markdig" Version="0.36.2"/>
         <PackageReference Include="Microsoft.AspNetCore.Components.Web" Version="8.0.3"/>
-        <PackageReference Include="Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation" Version="8.0.3"/>
         <PackageReference Include="Microsoft.Extensions.FileProviders.Embedded" Version="8.0.3"/>
         <PackageReference Include="NetBarcode" Version="1.7.0"/>
         <PackageReference Include="Pomelo.EntityFrameworkCore.MySql" Version="8.0.2"/>
@@ -45,10 +41,20 @@
         <PackageReference Include="Serilog.Extensions.Logging" Version="8.0.0"/>
         <PackageReference Include="Serilog.Sinks.Console" Version="5.0.1"/>
         <PackageReference Include="Serilog.Sinks.File" Version="5.0.0"/>
-        <PackageReference Include="SmartFormat.NET" Version="3.3.2"/>
         <PackageReference Include="X10D" Version="3.3.1"/>
         <PackageReference Include="X10D.Hosting" Version="3.3.1"/>
-        <PackageReference Include="ZString" Version="2.5.1"/>
+    </ItemGroup>
+
+    <ItemGroup>
+        <ProjectReference Include="..\OliverBooth.Common\OliverBooth.Common.csproj"/>
+        <ProjectReference Include="..\OliverBooth.Extensions.Markdig\OliverBooth.Extensions.Markdig.csproj"/>
+        <ProjectReference Include="..\OliverBooth.Extensions.SmartFormat\OliverBooth.Extensions.SmartFormat.csproj"/>
+    </ItemGroup>
+
+    <ItemGroup>
+        <Compile Update="Pages\Shared\Partials\PageTabsUtility.cs">
+            <DependentUpon>_PageTabs.cshtml</DependentUpon>
+        </Compile>
     </ItemGroup>
 
 </Project>

OliverBooth/Pages/Blog/Article.cshtml

@@ -1,13 +1,17 @@
 @page "/blog/{year:int}/{month:int}/{day:int}/{slug}"
 @using Humanizer
-@using OliverBooth.Data.Blog
+@using Markdig
-@using OliverBooth.Services
+@using Microsoft.AspNetCore.Mvc.TagHelpers
+@using OliverBooth.Common.Data
+@using OliverBooth.Common.Data.Blog
+@using OliverBooth.Common.Services
 @inject IBlogPostService BlogPostService
+@inject MarkdownPipeline MarkdownPipeline
 @model Article
 
 @if (Model.ShowPasswordPrompt)
 {
-    <div class="alert alert-danger" role="alert">
+    <div class="callout" data-callout="danger">
         This post is private and can only be viewed by those with the password.
     </div>
 
@@ -44,14 +48,14 @@
 
 @switch (post.Visibility)
 {
-    case BlogPostVisibility.Private:
+    case Visibility.Private:
-        <div class="alert alert-danger" role="alert">
+        <div class="callout" data-callout="danger">
             This post is private and can only be viewed by those with the password.
         </div>
         break;
 
-    case BlogPostVisibility.Unlisted:
+    case Visibility.Unlisted:
-        <div class="alert alert-warning" role="alert">
+        <div class="callout" data-callout="warning">
             This post is unlisted and can only be viewed by those with the link.
         </div>
         break;
@@ -73,19 +77,8 @@
             Updated @updated.Humanize()
         </abbr>
     }
-
-    @if (post.EnableComments)
-    {
-        <span>&bull;</span>
-        <a href="#disqus_thread" data-disqus-identifier="@post.GetDisqusIdentifier()">0 Comments</a>
-    }
 </p>
-<div class="post-tags">
+
-    @foreach (string tag in post.Tags)
-    {
-        <a asp-page="Index" asp-route-tag="@tag" class="badge bg-secondary">@tag</a>
-    }
-</div>
 <hr>
 
 <article>
@@ -94,6 +87,18 @@
 
 <hr>
 
+<div class="d-flex align-items-center mb-3">
+    <i data-lucide="tag"></i>
+    <ul class="ms-2 post-tags">
+        @foreach (string tag in post.Tags)
+        {
+            <li class="post-tag">
+                <a asp-page="Index" asp-route-tag="@Html.UrlEncoder.Encode(tag)">@tag</a>
+            </li>
+        }
+    </ul>
+</div>
+
 <div class="row">
     <div class="col-sm-12 col-md-6">
         @if (BlogPostService.GetPreviousPost(post) is { } previousPost)
@@ -131,31 +136,76 @@
 
 @if (post.EnableComments)
 {
-    <div id="disqus_thread"></div>
+    <div class="giscus"></div>
-    <script>
+    @section Scripts
-         var disqus_config = function () {
+    {
-             this.page.url = "@post.GetDisqusUrl()";
+        <script src="https://giscus.app/client.js"
-             this.page.identifier = "@post.GetDisqusIdentifier()";
+                data-repo="oliverbooth/oliverbooth.dev"
-             this.page.title = "@post.Title";
+                data-repo-id="MDEwOlJlcG9zaXRvcnkyNDUxODEyNDI="
-             this.page.postId = "@post.GetDisqusPostId()";
+                data-category="Comments"
-         };
+                data-category-id="DIC_kwDODp0rOs4Ce_Nj"
+                data-mapping="pathname"
+                data-strict="0"
+                data-reactions-enabled="1"
+                data-emit-metadata="0"
+                data-input-position="bottom"
+                data-theme="preferred_color_scheme"
+                data-lang="en"
+                crossorigin="anonymous"
+                async>
+</script>
+    }
 
-        (function() {
+    int commentCount = BlogPostService.GetLegacyCommentCount(post);
-            const d = document, s = d.createElement("script");
+    if (commentCount > 0)
-            s.async = true;
+    {
-            s.type = "text/javascript";
+        <hr>
-            s.src = "https://oliverbooth-dev.disqus.com/embed.js";
+
-            s.setAttribute("data-timestamp", (+ new Date()).toString());
+        var nestLevelMap = new Dictionary<ILegacyComment, int>();
-            (d.head || d.body).appendChild(s);
+        IReadOnlyList<ILegacyComment> legacyComments = BlogPostService.GetLegacyComments(post);
-        })();
+        var commentStack = new Stack<ILegacyComment>(legacyComments.OrderByDescending(c => c.CreatedAt));
-    </script>
+        <p class="text-center">
-    <script id="dsq-count-scr" src="https://oliverbooth-dev.disqus.com/count.js" async></script>
+            <strong>@("legacy comment".ToQuantity(commentCount))</strong>
-    <noscript>
+        </p>
-        Please enable JavaScript to view the
+        <p class="text-center">
-        <a href="https://disqus.com/?ref_noscript" rel="nofollow">
+            <sub>Legacy comments are comments that were posted using a commenting system that I no longer use. This exists for posterity.</sub>
-            comments powered by Disqus.
+        </p>
-        </a>
+
-    </noscript>
+        while (commentStack.Count > 0)
+        {
+            ILegacyComment comment = commentStack.Pop();
+            foreach (ILegacyComment reply in BlogPostService.GetLegacyReplies(comment).OrderByDescending(c => c.CreatedAt))
+            {
+                if (nestLevelMap.TryGetValue(comment, out int currentLevel))
+                {
+                    nestLevelMap[reply] = currentLevel + 1;
+                }
+                else
+                {
+                    nestLevelMap[reply] = 1;
+                }
+
+                commentStack.Push(reply);
+            }
+
+            int padding = 0;
+            if (nestLevelMap.TryGetValue(comment, out int nestLevel))
+            {
+                padding = 50 * nestLevel;
+            }
+
+            <div class="legacy-comment" style="margin-left: @(padding)px;">
+                <img class="blog-author-icon" src="@comment.GetAvatarUrl()" alt="@comment.Author">
+                @comment.Author &bull;
+
+                <abbr class="text-muted" data-bs-toggle="tooltip" data-bs-title="@comment.CreatedAt.ToString("dddd, d MMMM yyyy HH:mm")">
+                    @comment.CreatedAt.Humanize()
+                </abbr>
+
+                <div class="comment">@Html.Raw(Markdown.ToHtml(comment.Body, MarkdownPipeline))</div>
+            </div>
+        }
+    }
 }
 else
 {

OliverBooth/Pages/Blog/Article.cshtml.cs

@@ -1,8 +1,8 @@
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.RazorPages;
 using Microsoft.Extensions.Primitives;
-using OliverBooth.Data.Blog;
+using OliverBooth.Common.Data.Blog;
-using OliverBooth.Services;
+using OliverBooth.Common.Services;
 using BC = BCrypt.Net.BCrypt;
 
 namespace OliverBooth.Pages.Blog;
@@ -79,7 +79,6 @@ public class Article : PageModel
         var date = new DateOnly(year, month, day);
         if (!_blogPostService.TryGetPost(date, slug, out IBlogPost? post))
         {
-            Response.StatusCode = 404;
             return NotFound();
         }
 

OliverBooth/Pages/Blog/Index.cshtml

@@ -1,95 +1,27 @@
 @page
-@using Humanizer
+@using OliverBooth.Common.Data
-@using OliverBooth.Data.Mastodon
+@using OliverBooth.Common.Data.Blog
-@using OliverBooth.Services
+@using OliverBooth.Common.Services
 @model Index
-@inject IMastodonService MastodonService
+@inject IBlogPostService BlogPostService
 
 @{
     ViewData["Title"] = "Blog";
-    MastodonStatus latestStatus = MastodonService.GetLatestStatus();
-    bool doAprilFools = DateOnly.FromDateTime(DateTime.UtcNow) == new DateOnly(2024, 04, 01) || Environment.GetEnvironmentVariable("DO_AF") == "1";
 }
 
-@if (doAprilFools)
+@await Html.PartialAsync("Partials/_MastodonStatus")
+
+<div id="all-blog-posts">
+    @foreach (IBlogPost post in BlogPostService.GetBlogPosts(0, tags: Model.Tag))
+    {
+        @await Html.PartialAsync("Partials/_BlogCard", post)
+    }
+</div>
+
+@await Html.PartialAsync("Partials/_PageTabs", new ViewDataDictionary(ViewData)
 {
-    <h1>UNDER CONSTRUCTION</h1>
+    ["UrlRoot"] = "/blog",
-    <div style="text-align: center">
+    ["Page"] = 1,
-        <img src="~/img/construction_90x85.gif">
+    ["Tags"] = Model.Tag,
-        <img src="~/img/underconstruction_323x118.gif">
+    ["PageCount"] = BlogPostService.GetPageCount(visibility: Visibility.Published, tags: Model.Tag)
-        <img src="~/img/construction_90x85.gif">
+})
-        <p>Coming soon WATCH THIS SPACE</p>
-    </div>
-}
-else
-{
-    <div class="card text-center mastodon-update-card">
-        <div class="card-body">
-            @Html.Raw(latestStatus.Content)
-            @foreach (MediaAttachment attachment in latestStatus.MediaAttachments)
-            {
-                switch (attachment.Type)
-                {
-                    case AttachmentType.Audio:
-                        <p><audio controls="controls" src="@attachment.Url"></audio></p>
-                        break;
-
-                    case AttachmentType.Video:
-                        <p><video controls="controls" class="figure-img img-fluid" src="@attachment.Url"></video></p>
-                        break;
-
-                    case AttachmentType.Image:
-                    case AttachmentType.GifV:
-                        <p><img class="figure-img img-fluid" src="@attachment.Url"></p>
-                        break;
-                }
-            }
-        </div>
-        <div class="card-footer text-muted">
-            <abbr title="@latestStatus.CreatedAt.ToString("F")">@latestStatus.CreatedAt.Humanize()</abbr>
-            &bull;
-            <a href="@latestStatus.OriginalUri" target="_blank">View on Mastodon</a>
-        </div>
-    </div>
-
-    <div id="all-blog-posts">
-        @await Html.PartialAsync("_LoadingSpinner")
-    </div>
-
-    <script id="blog-post-template" type="text/x-handlebars-template">
-        <div class="card-header">
-            <span class="text-muted">
-                <img class="blog-author-icon" src="{{author.avatar}}" alt="{{author.name}}">
-                <span>{{author.name}}<span>
-                <span> &bull; </span>
-                <abbr title="{{ post.formattedDate }}">{{ post.date_humanized }}</abbr>
-                {{#if post.enable_comments}}
-                    <span> &bull; </span>
-                    <a href="{{post.url}}#disqus_thread" data-disqus-identifier="{{post.disqus_identifier}}">
-                        Loading comment count &hellip;
-                    </a>
-                {{/if}}
-            </span>
-        </div>
-        <div class="card-body">
-            <h2>
-                <a href="{{post.url}}"> {{post.title}}</a>
-            </h2>
-
-            <p>{{{post.excerpt}}}</p>
-
-            {{#if post.trimmed}}
-                <p>
-                    <a href="{{post.url}}">
-                        Read more...
-                    </a>
-                </p>
-            {{/if}}
-        </div>
-        <div class="card-footer">
-            {{#each post.tags}}
-                <a href="?tag={{urlEncode this}}" class="badge text-bg-dark">{{this}}</a>
-            {{/each}}
-        </div>
-    </script>
-}

OliverBooth/Pages/Blog/Index.cshtml.cs

@@ -1,7 +1,8 @@
+using System.Web;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.RazorPages;
-using OliverBooth.Data.Blog;
+using OliverBooth.Common.Data.Blog;
-using OliverBooth.Services;
+using OliverBooth.Common.Services;
 
 namespace OliverBooth.Pages.Blog;
 
@@ -15,11 +16,15 @@ public class Index : PageModel
         _blogPostService = blogPostService;
     }
 
+    public string[] Tag { get; private set; } = [];
+
     public IActionResult OnGet([FromQuery(Name = "pid")] Guid? postId = null,
-        [FromQuery(Name = "p")] int? wpPostId = null)
+        [FromQuery(Name = "p")] int? wpPostId = null,
+        [FromQuery(Name = "tag")] string? tag = null)
     {
         if (postId.HasValue == wpPostId.HasValue)
         {
+            Tag = (tag?.Split('+').Select(HttpUtility.UrlDecode).ToArray() ?? [])!;
             return Page();
         }
 
@@ -36,7 +41,7 @@ public class Index : PageModel
         return _blogPostService.TryGetPost(wpPostId, out IBlogPost? post) ? RedirectToPost(post) : NotFound();
     }
 
-    private IActionResult RedirectToPost(IBlogPost post)
+    private RedirectResult RedirectToPost(IBlogPost post)
     {
         var route = new
         {

OliverBooth/Pages/Blog/List.cshtml

@@ -0,0 +1,24 @@
+@page "/blog/page/{pageNumber:int}"
+@model List
+@using OliverBooth.Common.Data
+@using OliverBooth.Common.Data.Blog
+@using OliverBooth.Common.Services
+
+@inject IBlogPostService BlogPostService
+
+@await Html.PartialAsync("Partials/_MastodonStatus")
+
+<div id="all-blog-posts">
+    @foreach (IBlogPost post in BlogPostService.GetBlogPosts(Model.PageNumber - 1, tags: Model.Tag))
+    {
+        @await Html.PartialAsync("Partials/_BlogCard", post)
+    }
+</div>
+
+@await Html.PartialAsync("Partials/_PageTabs", new ViewDataDictionary(ViewData)
+{
+    ["UrlRoot"] = "/blog",
+    ["Page"] = Model.PageNumber,
+    ["Tags"] = Model.Tag,
+    ["PageCount"] = BlogPostService.GetPageCount(visibility: Visibility.Published, tags: Model.Tag)
+})

OliverBooth/Pages/Blog/List.cshtml.cs

@@ -0,0 +1,37 @@
+using System.Web;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.RazorPages;
+
+namespace OliverBooth.Pages.Blog;
+
+/// <summary>
+///     Represents a class which defines the model for the <c>/blog/page/#</c> route.
+/// </summary>
+public class List : PageModel
+{
+    /// <summary>
+    ///     Gets the requested page number.
+    /// </summary>
+    /// <value>The requested page number.</value>
+    public int PageNumber { get; private set; }
+
+    public string[] Tag { get; private set; } = [];
+
+    /// <summary>
+    ///     Handles the incoming GET request to the page.
+    /// </summary>
+    /// <param name="page">The requested page number, starting from 1.</param>
+    /// <param name="tag">The tag by which to filter results.</param>
+    /// <returns></returns>
+    public IActionResult OnGet([FromRoute(Name = "pageNumber")] int page = 1, [FromQuery(Name = "tag")] string? tag = null)
+    {
+        if (page < 2)
+        {
+            return RedirectToPage("Index");
+        }
+
+        PageNumber = page;
+        Tag = (tag?.Split('+').Select(HttpUtility.UrlDecode).ToArray() ?? [])!;
+        return Page();
+    }
+}

OliverBooth/Pages/Blog/RawArticle.cshtml.cs

@@ -1,8 +1,8 @@
 using Cysharp.Text;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.RazorPages;
-using OliverBooth.Data.Blog;
+using OliverBooth.Common.Data.Blog;
-using OliverBooth.Services;
+using OliverBooth.Common.Services;
 
 namespace OliverBooth.Pages.Blog;
 

OliverBooth/Pages/Books.cshtml

@@ -1,5 +1,5 @@
 @page
-@using OliverBooth.Data.Web
+@using OliverBooth.Common.Data.Web
 @model OliverBooth.Pages.Books
 @{
     ViewData["Title"] = "Reading List";

OliverBooth/Pages/Books.cshtml.cs

@@ -1,6 +1,6 @@
 using Microsoft.AspNetCore.Mvc.RazorPages;
-using OliverBooth.Data.Web;
+using OliverBooth.Common.Data.Web;
-using OliverBooth.Services;
+using OliverBooth.Common.Services;
 
 namespace OliverBooth.Pages;
 

OliverBooth/Pages/Contact/Blacklist.cshtml

@@ -1,6 +1,7 @@
 @page
-@using OliverBooth.Data.Web
+@using Microsoft.AspNetCore.Mvc.TagHelpers
-@using OliverBooth.Services
+@using OliverBooth.Common.Data.Web
+@using OliverBooth.Common.Services
 @inject IContactService ContactService
 @{
     ViewData["Title"] = "Blacklist";

OliverBooth/Pages/Contact/Index.cshtml

@@ -1,4 +1,5 @@
 @page
+@using Microsoft.AspNetCore.Mvc.TagHelpers
 @{
     ViewData["Title"] = "Contact";
 }
@@ -11,29 +12,31 @@
         if I can.
     </p>
 
-    <div class="alert alert-warning">
+    <div class="callout" data-callout="warning">
-        <p class="lead"><i class="fa-solid fa-triangle-exclamation"></i> Spam warning</p>
+        <div class="callout-title"><i data-lucide="triangle-alert"></i> Spam Warning</div>
-        <p>
+        <div class="callout-content">
             I am politely asking that you respect my inbox and keep your unsolicited advertising away. This is a simple
             request. If you send me any kind of spam after this, you have demonstrated that you do not have the basic
             human decency to respect my wishes or my privacy, and you have lost the privilege for me to respect yours. I
             <strong>will</strong> block your email address, and I will add your name to my public blacklist of spammers,
             which you can find <a asp-page="/Contact/Blacklist">here</a>.
-        </p>
+        </div>
     </div>
 
-    <div class="alert alert-info">
+    <div class="callout" data-callout="tip">
-        <p class="lead"><i class="fa-solid fa-circle-info"></i> Dear SEO marketing teams</p>
+        <div class="callout-title"><i data-lucide="info"></i> Dear SEO marketing teams</div>
-        <p>
+        <div class="callout-content">
-            I have given you enough chances. I asked that you do not send me any SEO offers or else be blocked.
+            <p>
-            Congratulations, you've been upgraded to "spammer" and will receive the same treatment as any other bad
+                I have given you enough chances. I asked that you do not send me any SEO offers or else be blocked.
-            actor sending unsolicited crap.
+                Congratulations, you've been upgraded to "spammer" and will receive the same treatment as any other bad
-        </p>
+                actor sending unsolicited crap.
-        <p>
+            </p>
-            If I receive any SEO emails, you will be added to the blacklist and your company name will be shamed too. I
+            <p>
-            will make my best efforts to ensure no one ever uses you. If you cannot respect the privacy of my inbox, I
+                If I receive any SEO emails, you will be added to the blacklist and your company name will be shamed
-            will never respect you or your company.
+                too. I will make my best efforts to ensure no one ever uses you. If you cannot respect the privacy of my
-        </p>
+                inbox, I will never respect you or your company.
+            </p>
+        </div>
     </div>
 
     <form method="post" asp-controller="Contact" asp-action="HandleForm">

OliverBooth/Pages/Contact/Result.cshtml

@@ -1,4 +1,5 @@
 @page
+@using Microsoft.AspNetCore.Mvc.TagHelpers
 @model OliverBooth.Pages.Contact.Result
 
 @{

OliverBooth/Pages/Error.cshtml

@@ -1,34 +0,0 @@
-@page "/error/{code:int?}"
-@model OliverBooth.Pages.ErrorModel
-@{
-    Layout = "_MinimalLayout";
-    ViewData["Title"] = "Error";
-}
-
-<h2 class="text-danger">
-    @switch (Model.HttpStatusCode)
-    {
-        case 403:
-            <span>403 Forbidden</span>
-            break;
-
-        case 404:
-            <span>404 Page not found</span>
-            break;
-
-        case 500:
-            <span>Internal server error</span>
-            break;
-
-        default:
-            <span>Something went wrong</span>
-            break;
-    }
-</h2>
-
-@if (Model.ShowRequestId)
-{
-    <p>
-        <strong>Request ID:</strong> <code>@Model.RequestId</code>
-    </p>
-}

OliverBooth/Pages/Error.cshtml.cs

@@ -1,28 +0,0 @@
-using System.Diagnostics;
-using Microsoft.AspNetCore.Mvc;
-using Microsoft.AspNetCore.Mvc.RazorPages;
-
-namespace OliverBooth.Pages;
-
-[ResponseCache(Duration = 0, Location = ResponseCacheLocation.None, NoStore = true)]
-[IgnoreAntiforgeryToken]
-public class ErrorModel : PageModel
-{
-    public string? RequestId { get; set; }
-
-    public bool ShowRequestId => !string.IsNullOrEmpty(RequestId);
-
-    public int HttpStatusCode { get; private set; }
-
-    public IActionResult OnGet(int? code = null)
-    {
-        HttpStatusCode = code ?? HttpContext.Response.StatusCode;
-        if (HttpStatusCode == 200)
-        {
-            return RedirectToPage("/Index");
-        }
-
-        RequestId = Activity.Current?.Id ?? HttpContext.TraceIdentifier;
-        return Page();
-    }
-}

OliverBooth/Pages/Error/BadRequest.cshtml

@@ -0,0 +1,17 @@
+@page "/error/400"
+<article>
+    <div class="d-flex align-items-center justify-content-center">
+        <div class="d-flex flex-column align-items-center justify-content-center">
+            <div class="p-2">
+                <h1 class="text-center">400 Bad Request</h1>
+            </div>
+            <div class="p-2">
+                <p class="text-center">Received invalid request message. Check your request and try again.</p>
+            </div>
+        </div>
+
+        <div class="align-self-stretch">
+            <img class="img-fluid" src="~/img/error/400-bad-request.png">
+        </div>
+    </div>
+</article>

OliverBooth/Pages/Error/Forbidden.cshtml

@@ -0,0 +1,15 @@
+@page "/error/403"
+<article>
+    <div class="text-center d-flex flex-column align-items-center">
+        <div class="p-2">
+            <h1 class="text-center">403 Forbidden</h1>
+        </div>
+        <div class="p-2">
+            <img class="img-fluid" src="~/img/error/403-forbidden.png">
+        </div>
+
+        <div class="p-2">
+            <p class="text-center">Access to the requested page is forbidden.</p>
+        </div>
+    </div>
+</article>

OliverBooth/Pages/Error/GatewayTimeout.cshtml

@@ -0,0 +1,17 @@
+@page "/error/504"
+<article>
+    <div class="d-flex align-items-center justify-content-center">
+        <div class="align-self-stretch">
+            <img class="img-fluid" src="~/img/error/504-gateway-timeout.png">
+        </div>
+
+        <div class="d-flex flex-column align-items-center justify-content-center">
+            <div class="p-2">
+                <h1 class="text-center">504 Gateway Timeout</h1>
+            </div>
+            <div class="p-2">
+                <p class="text-center">The server is slacking. Give it more coffee.</p>
+            </div>
+        </div>
+    </div>
+</article>

OliverBooth/Pages/Error/Gone.cshtml

@@ -0,0 +1,17 @@
+@page "/error/400"
+<article>
+    <div class="d-flex align-items-center justify-content-center">
+        <div class="d-flex flex-column align-items-center justify-content-center">
+            <div class="p-2">
+                <h1 class="text-center">410 Gone</h1>
+            </div>
+            <div class="p-2">
+                <p class="text-center">The requested page has mysteriously disappeared.</p>
+            </div>
+        </div>
+
+        <div class="align-self-stretch">
+            <img class="img-fluid" src="~/img/error/410-gone.png">
+        </div>
+    </div>
+</article>

OliverBooth/Pages/Error/ImATeapot.cshtml

@@ -0,0 +1,17 @@
+@page "/error/418"
+<article>
+    <div class="d-flex align-items-center justify-content-center">
+        <div class="align-self-stretch">
+            <img class="img-fluid" src="~/img/error/418-im-a-teapot.png">
+        </div>
+
+        <div class="d-flex flex-column align-items-center justify-content-center">
+            <div class="p-2">
+                <h1 class="text-center">418 I'm A Teapot</h1>
+            </div>
+            <div class="p-2">
+                <p class="text-center">No coffee available. I am only capable of brewing tea.</p>
+            </div>
+        </div>
+    </div>
+</article>

OliverBooth/Pages/Error/InternalServerError.cshtml

@@ -0,0 +1,17 @@
+@page "/error/500"
+<article>
+    <div class="d-flex align-items-center justify-content-center">
+        <div class="align-self-stretch">
+            <img class="img-fluid" src="~/img/error/500-internal-server-error.png">
+        </div>
+
+        <div class="d-flex flex-column align-items-center justify-content-center">
+            <div class="p-2">
+                <h1 class="text-center">500 Internal Server Error</h1>
+            </div>
+            <div class="p-2">
+                <p class="text-center">This is my fault, not yours.</p>
+            </div>
+        </div>
+    </div>
+</article>