context command to pin messages in respective thread #1188

application/src/main/java/org/togetherjava/tjbot/features/Features.java

@@ -32,6 +32,7 @@
 import org.togetherjava.tjbot.features.help.HelpThreadLifecycleListener;
 import org.togetherjava.tjbot.features.help.HelpThreadMetadataPurger;
 import org.togetherjava.tjbot.features.help.MarkHelpThreadCloseInDBRoutine;
+import org.togetherjava.tjbot.features.help.PinAnswerCommand;
 import org.togetherjava.tjbot.features.help.PinnedNotificationRemover;
 import org.togetherjava.tjbot.features.javamail.RSSHandlerRoutine;
 import org.togetherjava.tjbot.features.jshell.JShellCommand;
@@ -160,6 +161,7 @@ public static Collection<Feature> createFeatures(JDA jda, Database database, Con
 
         // Message context commands
         features.add(new TransferQuestionCommand(config, chatGptService));
+        features.add(new PinAnswerCommand(config));
 
         // User context commands
 

application/src/main/java/org/togetherjava/tjbot/features/help/PinAnswerCommand.java

@@ -0,0 +1,81 @@
+package org.togetherjava.tjbot.features.help;
+
+import net.dv8tion.jda.api.entities.Message;
+import net.dv8tion.jda.api.entities.User;
+import net.dv8tion.jda.api.entities.channel.concrete.ForumChannel;
+import net.dv8tion.jda.api.entities.channel.concrete.ThreadChannel;
+import net.dv8tion.jda.api.events.interaction.command.MessageContextInteractionEvent;
+import net.dv8tion.jda.api.interactions.commands.build.Commands;
+
+import org.togetherjava.tjbot.config.Config;
+import org.togetherjava.tjbot.config.HelpSystemConfig;
+import org.togetherjava.tjbot.features.BotCommandAdapter;
+import org.togetherjava.tjbot.features.CommandVisibility;
+import org.togetherjava.tjbot.features.MessageContextCommand;
+
+public final class PinAnswerCommand extends BotCommandAdapter implements MessageContextCommand {
+    private static final String COMMAND_NAME = "pin-answer";
+    private static final int MAX_PINNED_ANSWERS = 10;
+    private final String helpForumPattern;
+
+    public PinAnswerCommand(Config config) {
+        super(Commands.message(COMMAND_NAME), CommandVisibility.GUILD);
+        HelpSystemConfig helpConfig = config.getHelpSystem();
+        helpForumPattern = helpConfig.getHelpForumPattern();
+    }
+
+    @Override
+    public void onMessageContext(MessageContextInteractionEvent event) {
+        Message originalMessage = event.getTarget();
+        User commandInvoker = event.getUser();
+
+        if (!(originalMessage.getChannel() instanceof ThreadChannel threadChannel)) {
+            replyNotInThread(event);
+            return;
+        }
+
+        if (!(threadChannel.getParentChannel() instanceof ForumChannel forumChannel)
+                || !forumChannel.getName().equalsIgnoreCase(helpForumPattern)) {
+            replyNotInThread(event);
+            return;
+        }
+
+        if (!threadOwner(commandInvoker, threadChannel)) {
+            replyNotThreadOwner(event);
+            return;
+        }
+
+        threadChannel.retrievePinnedMessages().queue(pinnedMessages -> {
+            if (pinnedMessages.size() >= MAX_PINNED_ANSWERS) {
+                replyMaxPinsReached(event);
+            } else {
+                pinMessage(event, originalMessage);
+            }
+        });
+    }
+
+    private boolean threadOwner(User user, ThreadChannel thread) {
+        return user.getIdLong() == thread.getOwnerIdLong();
+    }
+
+    private void pinMessage(MessageContextInteractionEvent event, Message message) {
+        message.pin()
+            .queue(success -> event.reply("Answer pinned successfully!").setEphemeral(true).queue(),
+                    failure -> event.reply("Failed to pin the answer.").setEphemeral(true).queue());
+    }
+
+    private void replyNotInThread(MessageContextInteractionEvent event) {
+        event.reply("This command can only be used in threads").setEphemeral(true).queue();
+    }
+
+    private void replyNotThreadOwner(MessageContextInteractionEvent event) {
+        event.reply("Only thread owners can use this command").setEphemeral(true).queue();
+    }
+
+    private void replyMaxPinsReached(MessageContextInteractionEvent event) {
+        event.reply("You've reached a maximum pinned limit (" + MAX_PINNED_ANSWERS
+                + ") for threads, if you wish to pin more messages please remove a few existing pinned messages")
+            .setEphemeral(true)
+            .queue();
+    }
+}