Add RSS feed generator

README.md

@@ -33,3 +33,19 @@ Claude Haiku 4.5
 
 - [dotnet/runtime](https://github.com/dotnet/runtime)
 - [Claude Docs - Models overview](https://platform.claude.com/docs/en/about-claude/models/overview)
+
+## Third-party Notices
+
+### Material Design Icons
+
+- Icon: rss
+- URL: https://pictogrammers.com/library/mdi/icon/rss/
+- Copyright (c) 2014 Austin Andrews (https://templarian.com/)
+- Licensed under the [Apache License, Version 2.0](https://github.com/Templarian/MaterialDesign/blob/master/LICENSE)
+
+### GitHub Octicons
+
+- Icon: mark-github
+- URL: https://github.com/primer/octicons/blob/main/icons/mark-github-24.svg
+- Copyright (c) 2012 GitHub, Inc.
+- Licensed under the [MIT License](https://github.com/primer/octicons/blob/main/LICENSE)

src/PRDigest.NET/MarkdownOptions.cs

@@ -0,0 +1,12 @@
+using Markdig;
+using Markdig.Extensions.AutoIdentifiers;
+
+namespace PRDigest.NET;
+
+internal static class MarkdownOptions
+{
+    public static readonly MarkdownPipeline Pipeline = new MarkdownPipelineBuilder()
+        .UseAutoIdentifiers(AutoIdentifierOptions.GitHub)
+        .UseAdvancedExtensions()
+        .Build();
+}

src/PRDigest.NET/Program.cs

@@ -3,6 +3,8 @@
 using Anthropic.Models.Messages;
 using Octokit;
 using PRDigest.NET;
+using System.Globalization;
+using System.Runtime.InteropServices;
 using System.Text;
 
 if (args.Length == 0) return;
@@ -20,6 +22,9 @@
 // convert all markdown files to HTML
 await CreateHtml(archivesDir, outputsDir);
 
+// (Re)create RSS feed from archived markdown files
+await CreateRss(archivesDir, outputsDir);
+
 // end
 var endTime = TimeProvider.System.GetTimestamp();
 Console.WriteLine($"Total elapsed time: {TimeProvider.System.GetElapsedTime(startTime, endTime).TotalSeconds} seconds.");
@@ -68,7 +73,7 @@ async ValueTask SummarizeCurrentPullRequestAndCreate(string archivesDir, string
     if (string.IsNullOrEmpty(markdown)) return;
 
     // Save markdown and HTML files.
-    var html = HtmlGenereator.GenerateHtmlFromMarkdown($"{year}年{month}月{day}日", markdown);
+    var html = HtmlGenerator.GenerateHtmlFromMarkdown($"{year}年{month}月{day}日", markdown);
     var markdownTask = File.WriteAllTextAsync(Path.Combine(archivesDir, year, month, $"{day}.md"), markdown);
     var htmlTask = File.WriteAllTextAsync(Path.Combine(outputsDir, year, month, $"{day}.html"), html);
     await Task.WhenAll(markdownTask, htmlTask);
@@ -260,6 +265,37 @@ async ValueTask<string> SummarizePullRequestAsync(PullRequestInfo[] pullRequestI
     return $"{tableOfContentsBuilder}{separator}{markdownlBuilder}";
 }
 
+async ValueTask CreateRss(string archivesDir, string outputsDir)
+{
+    const int MaxDays = 3;
+    var comparer = StringComparer.Create(CultureInfo.InvariantCulture, CompareOptions.NumericOrdering);
+
+    var items = new List<(string target, string markdownContent)>(MaxDays);
+    foreach (var yearDir in Directory.EnumerateDirectories(archivesDir).OrderDescending(comparer))
+    {
+        var year = Path.GetFileName(yearDir);
+
+        foreach (var monthDir in Directory.EnumerateDirectories(yearDir).OrderDescending(comparer))
+        {
+            var month = Path.GetFileName(monthDir);
+
+            foreach (var mdFilePath in Directory.EnumerateFiles(monthDir, "*.md").OrderDescending(comparer))
+            {
+                if (items.Count >= MaxDays) goto END;
+                var day = Path.GetFileNameWithoutExtension(mdFilePath);
+                var markdown = await File.ReadAllTextAsync(mdFilePath);
+                items.Add(($"{year}/{month}/{day}", markdown));
+            }
+        }
+    }
+
+    if (items.Count == 0) return;
+
+END:
+    var rssContent = RssFeedGenerator.Generate(CollectionsMarshal.AsSpan(items));
+    await File.WriteAllTextAsync(Path.Combine(outputsDir, $"feed.xml"), rssContent);
+}
+
 async ValueTask CreateHtml(string archivesDir, string outputsDir)
 {
     // set up archives directory
@@ -274,36 +310,36 @@ async ValueTask CreateHtml(string archivesDir, string outputsDir)
         Directory.CreateDirectory(outputsDir);
     }
 
-    foreach (var yearDirs in Directory.GetDirectories(archivesDir))
+    foreach (var yearDirs in Directory.EnumerateDirectories(archivesDir))
     {
         var year = Path.GetFileName(yearDirs);
         if (!Directory.Exists(Path.Combine(outputsDir, year)))
         {
             Directory.CreateDirectory(Path.Combine(outputsDir, year));
         }
 
-        foreach (var monthDirss in Directory.GetDirectories(yearDirs))
+        foreach (var monthDirss in Directory.EnumerateDirectories(yearDirs))
         {
             var month = Path.GetFileName(monthDirss);
             if (!Directory.Exists(Path.Combine(outputsDir, year, month)))
             {
                 Directory.CreateDirectory(Path.Combine(outputsDir, year, month));
             }
 
-            await Parallel.ForEachAsync(Directory.GetFiles(monthDirss, "*.md"), async (dayFiles, _) =>
+            await Parallel.ForEachAsync(Directory.EnumerateFiles(monthDirss, "*.md"), async (dayFiles, _) =>
             {
                 var day = Path.GetFileNameWithoutExtension(dayFiles);
                 var markdown = await File.ReadAllTextAsync(dayFiles);
 
                 // ./yyyy/mm/dd.html
-                var html = HtmlGenereator.GenerateHtmlFromMarkdown($"{year}年{month}月{day}日", markdown);
+                var html = HtmlGenerator.GenerateHtmlFromMarkdown($"{year}年{month}月{day}日", markdown);
                 await File.WriteAllTextAsync(Path.Combine(outputsDir, year, month, $"{day}.html"), html);
             });
         }
     }
 
     // set up index.html
-    await File.WriteAllTextAsync(Path.Combine(outputsDir, "index.html"), HtmlGenereator.GenerateIndex(archivesDir, outputsDir));
+    await File.WriteAllTextAsync(Path.Combine(outputsDir, "index.html"), HtmlGenerator.GenerateIndex(archivesDir, outputsDir));
 }
 
 internal sealed class PullRequestInfo