Implement private messaging system for bot communications

- Add IPrivateMessageTrigger interface for private messaging support
- Extend GitHubStorage with SendPrivateMessage and CreateMinimalIssueComment methods
- Update IssueTracker to handle private message triggers differently
- Convert LastCommitActivityTrigger and OrganizationLastMonthActivityTrigger to use private messaging
- Add setup documentation and examples

This addresses issue #37 by sending detailed bot messages to a private
bot-communications repository instead of cluttering public issue threads.
Users are notified via mentions and get email notifications, while the
original issue threads remain clean and readable.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: konard

csharp/Interfaces/IPrivateMessageTrigger.cs

@@ -0,0 +1,61 @@
+using System.Threading.Tasks;
+
+namespace Interfaces
+{
+    /// <summary>
+    /// <para>
+    /// Defines a trigger that supports private messaging to users instead of public issue comments.
+    /// </para>
+    /// <para></para>
+    /// </summary>
+    public interface IPrivateMessageTrigger<TContext> : ITrigger<TContext>
+    {
+        /// <summary>
+        /// <para>
+        /// Gets the user login to send private message to.
+        /// </para>
+        /// <para></para>
+        /// </summary>
+        /// <param name="context">
+        /// <para>The context.</para>
+        /// <para></para>
+        /// </param>
+        /// <returns>
+        /// <para>The user login string</para>
+        /// <para></para>
+        /// </returns>
+        string GetTargetUserLogin(TContext context);
+
+        /// <summary>
+        /// <para>
+        /// Gets the subject for the private message.
+        /// </para>
+        /// <para></para>
+        /// </summary>
+        /// <param name="context">
+        /// <para>The context.</para>
+        /// <para></para>
+        /// </param>
+        /// <returns>
+        /// <para>The message subject</para>
+        /// <para></para>
+        /// </returns>
+        string GetMessageSubject(TContext context);
+
+        /// <summary>
+        /// <para>
+        /// Gets the private message content.
+        /// </para>
+        /// <para></para>
+        /// </summary>
+        /// <param name="context">
+        /// <para>The context.</para>
+        /// <para></para>
+        /// </param>
+        /// <returns>
+        /// <para>The private message content</para>
+        /// <para></para>
+        /// </returns>
+        Task<string> GetPrivateMessageContent(TContext context);
+    }
+}

csharp/Platform.Bot/Trackers/IssueTracker.cs

@@ -74,10 +74,27 @@ public async Task Start(CancellationToken cancellationToken)
                     }
                     if (await trigger.Condition(issue))
                     {
-                        await trigger.Action(issue);
+                        if (trigger is IPrivateMessageTrigger<Issue> privateMessageTrigger)
+                        {
+                            await HandlePrivateMessageTrigger(issue, privateMessageTrigger);
+                        }
+                        else
+                        {
+                            await trigger.Action(issue);
+                        }
                     }
                 }
             }
         }
+
+        private async Task HandlePrivateMessageTrigger(Issue issue, IPrivateMessageTrigger<Issue> trigger)
+        {
+            var targetUser = trigger.GetTargetUserLogin(issue);
+            var subject = trigger.GetMessageSubject(issue);
+            var messageContent = await trigger.GetPrivateMessageContent(issue);
+
+            var privateMessageIssue = await _storage.SendPrivateMessage(targetUser, subject, messageContent);
+            await _storage.CreateMinimalIssueComment(issue.Repository.Id, issue.Number, targetUser, subject, privateMessageIssue);
+        }
     }
 }

csharp/Platform.Bot/Triggers/LastCommitActivityTrigger.cs

@@ -13,7 +13,7 @@
 namespace Platform.Bot.Triggers
 {
     using TContext = Issue;
-    internal class LastCommitActivityTrigger : ITrigger<TContext>
+    internal class LastCommitActivityTrigger : IPrivateMessageTrigger<TContext>
     {
         private readonly GitHubStorage _githubStorage;
 
@@ -25,14 +25,30 @@ public async Task<bool> Condition(TContext issue)
         }
 
         public async Task Action(TContext issue)
+        {
+            Console.WriteLine($"Issue {issue.Title} is processed: {issue.HtmlUrl}");
+            await _githubStorage.Client.Issue.Update(issue.Repository.Owner.Login, issue.Repository.Name, issue.Number, new IssueUpdate() { State = ItemState.Closed });
+        }
+
+        public string GetTargetUserLogin(TContext issue)
+        {
+            return issue.User.Login;
+        }
+
+        public string GetMessageSubject(TContext issue)
+        {
+            return "Last 3 Months Commit Activity Report";
+        }
+
+        public async Task<string> GetPrivateMessageContent(TContext issue)
         {
             var organizationName = issue.Repository.Owner.Login;
 
             var allMembers = await _githubStorage.GetAllOrganizationMembers(organizationName);
             var allRepositories = await _githubStorage.GetAllRepositories(organizationName);
             if (!allRepositories.Any())
             {
-                return;
+                return "No repositories found in the organization.";
             }
 
             var commitsPerUserInLast3Months = await allRepositories
@@ -54,16 +70,15 @@ public async Task Action(TContext issue)
                     }
                     return dictionary;
                 });
+            
             StringBuilder messageSb = new();
             var ShortSummaryMessage = GetShortSummaryMessage(commitsPerUserInLast3Months.Select(pair => pair.Key).ToList());
             messageSb.Append(ShortSummaryMessage);
             messageSb.AppendLine("---");
             var detailedMessage = await GetDetailedMessage(commitsPerUserInLast3Months);
             messageSb.Append(detailedMessage);
-            var message = messageSb.ToString();
-            await _githubStorage.CreateIssueComment(issue.Repository.Id, issue.Number, message);
-            Console.WriteLine($"Issue {issue.Title} is processed: {issue.HtmlUrl}");
-            await _githubStorage.Client.Issue.Update(issue.Repository.Owner.Login, issue.Repository.Name, issue.Number, new IssueUpdate() { State = ItemState.Closed });
+            
+            return messageSb.ToString();
         }
 
         private string GetShortSummaryMessage(List<User> users)

csharp/Platform.Bot/Triggers/OrganizationLastMonthActivityTrigger.cs

@@ -17,7 +17,7 @@ namespace Platform.Bot.Triggers
     /// <para></para>
     /// </summary>
     /// <seealso cref="ITrigger{Issue}"/>
-    internal class OrganizationLastMonthActivityTrigger : ITrigger<TContext>
+    internal class OrganizationLastMonthActivityTrigger : IPrivateMessageTrigger<TContext>
     {
         private readonly GitHubStorage _storage;
         private readonly Parser _parser = new();
@@ -62,11 +62,24 @@ internal class OrganizationLastMonthActivityTrigger : ITrigger<TContext>
         /// </param>
         public async Task Action(TContext context)
         {
-            var issueService = _storage.Client.Issue;
+            _storage.CloseIssue(context);
+        }
+
+        public string GetTargetUserLogin(TContext context)
+        {
+            return context.User.Login;
+        }
+
+        public string GetMessageSubject(TContext context)
+        {
+            return "Organization Last Month Activity Report";
+        }
+
+        public async Task<string> GetPrivateMessageContent(TContext context)
+        {
             var owner = context.Repository.Owner.Login;
             var activeUsersString = string.Join("\n", GetActiveUsers(GetIgnoredRepositories(_parser.Parse(context.Body)), owner));
-            issueService.Comment.Create(owner, context.Repository.Name, context.Number, activeUsersString);
-            _storage.CloseIssue(context);
+            return $"# Organization Last Month Activity\n\nActive users in the last month:\n\n{activeUsersString}";
         }
 
         /// <summary>

csharp/Storage/RemoteStorage/GitHubStorage.cs

@@ -307,6 +307,33 @@ public Task<IssueComment> CreateIssueComment(long repositoryId, int issueNumber,
             return Client.Issue.Comment.Create(repositoryId, issueNumber, message);
         }
 
+        public async Task<Issue> SendPrivateMessage(string userLogin, string subject, string message, string botCommunicationRepoName = "bot-communications")
+        {
+            try
+            {
+                var repo = await Client.Repository.Get(Owner, botCommunicationRepoName);
+                var issueTitle = $"Message for @{userLogin}: {subject}";
+                var issueBody = $"@{userLogin}\n\n{message}";
+                
+                var newIssue = new NewIssue(issueTitle)
+                {
+                    Body = issueBody
+                };
+                
+                return await Client.Issue.Create(repo.Id, newIssue);
+            }
+            catch (NotFoundException)
+            {
+                throw new InvalidOperationException($"Bot communication repository '{botCommunicationRepoName}' not found. Please create this repository first.");
+            }
+        }
+
+        public async Task<IssueComment> CreateMinimalIssueComment(long repositoryId, int issueNumber, string userLogin, string subject, Issue privateMessageIssue)
+        {
+            var message = $"@{userLogin} Bot message sent privately: [{subject}]({privateMessageIssue.HtmlUrl})";
+            return await Client.Issue.Comment.Create(repositoryId, issueNumber, message);
+        }
+
         #endregion
 
         #region Branch

examples/bot-communication-setup.md

@@ -0,0 +1,50 @@
+# Bot Communication Setup
+
+This example shows how to set up the private messaging system for the bot.
+
+## Prerequisites
+
+1. Create a private repository called `bot-communications` in your organization
+2. Make sure the bot has access to this repository
+
+## How it works
+
+When a trigger implements `IPrivateMessageTrigger<Issue>` instead of `ITrigger<Issue>`:
+
+1. The bot generates the message content privately
+2. Creates an issue in the `bot-communications` repository with the message
+3. Mentions the target user in that issue (so they get email notification)
+4. Posts a minimal comment in the original issue with a link to the private message
+
+## Example Usage
+
+```csharp
+// Old way - creates big public comments
+internal class MyTrigger : ITrigger<Issue> 
+{
+    public async Task Action(Issue issue) 
+    {
+        await _github.CreateIssueComment(issue.Repository.Id, issue.Number, "Very long message...");
+    }
+}
+
+// New way - sends private messages
+internal class MyTrigger : IPrivateMessageTrigger<Issue> 
+{
+    public string GetTargetUserLogin(Issue issue) => issue.User.Login;
+    public string GetMessageSubject(Issue issue) => "Report Title";
+    public async Task<string> GetPrivateMessageContent(Issue issue) => "Very long message...";
+    public async Task Action(Issue issue) 
+    {
+        // Only handle issue closing, messaging is automatic
+        await _github.Client.Issue.Update(issue.Repository.Owner.Login, issue.Repository.Name, issue.Number, new IssueUpdate() { State = ItemState.Closed });
+    }
+}
+```
+
+## Benefits
+
+- ✅ Reduces clutter in main issue threads
+- ✅ Users still get notified via email mentions
+- ✅ Messages are preserved in a dedicated space
+- ✅ Original issues stay clean and readable