Add Automated Help Channel Moderation System [Beta]

src/main/java/com/javadiscord/javabot/Bot.java

@@ -2,6 +2,7 @@
 
 import com.javadiscord.javabot.data.H2DataSource;
 import com.javadiscord.javabot.events.*;
+import com.javadiscord.javabot.help.HelpChannelListener;
 import com.javadiscord.javabot.properties.config.BotConfig;
 import net.dv8tion.jda.api.JDA;
 import net.dv8tion.jda.api.JDABuilder;
@@ -92,7 +93,8 @@ private static void addEventListeners(JDA jda) {
                 new AutoMod(),
                 new SubmissionListener(),
                 new StarboardListener(),
-                new InteractionListener()
+                new InteractionListener(),
+                new HelpChannelListener()
         );
     }
 }

src/main/java/com/javadiscord/javabot/events/InteractionListener.java

@@ -2,11 +2,12 @@
 
 import com.google.gson.JsonObject;
 import com.google.gson.JsonParser;
+import com.javadiscord.javabot.Bot;
+import com.javadiscord.javabot.help.HelpChannelManager;
 import com.mongodb.client.MongoCollection;
 import com.mongodb.client.MongoDatabase;
-import net.dv8tion.jda.api.entities.Guild;
-import net.dv8tion.jda.api.entities.Member;
-import net.dv8tion.jda.api.entities.Role;
+import lombok.extern.slf4j.Slf4j;
+import net.dv8tion.jda.api.entities.*;
 import net.dv8tion.jda.api.events.interaction.ButtonClickEvent;
 import net.dv8tion.jda.api.hooks.ListenerAdapter;
 import org.bson.Document;
@@ -15,6 +16,7 @@
 import static com.javadiscord.javabot.events.Startup.preferredGuild;
 import static com.mongodb.client.model.Filters.eq;
 
+@Slf4j
 public class InteractionListener extends ListenerAdapter {
 
 	// TODO: add Context-Menu Commands (once they're available in JDA)
@@ -31,6 +33,7 @@ public void onButtonClick(ButtonClickEvent event) {
 			case "dm-submission" -> this.handleDmSubmission(database, guild, event);
 			case "submission" -> this.handleSubmission(database, guild, event);
 			case "reaction-role" -> this.handleReactionRoles(event);
+			case "help-channel" -> this.handleHelpChannel(event, id[1]);
 		}
 	}
 
@@ -81,4 +84,30 @@ private void handleReactionRoles(ButtonClickEvent event) {
 			event.getHook().sendMessage("Added Role: " + role.getAsMention()).setEphemeral(true).queue();
 		}
 	}
+
+	private void handleHelpChannel(ButtonClickEvent event, String action) {
+		var config = Bot.config.get(event.getGuild()).getHelp();
+		var channelManager = new HelpChannelManager(config);
+		TextChannel channel = event.getTextChannel();
+		User owner = channelManager.getReservedChannelOwner(channel);
+		if (owner == null) {
+			return; // This channel will be pruned automatically.
+		}
+
+		if (
+			event.getUser().equals(owner) ||
+			(event.getMember() != null && event.getMember().getRoles().contains(Bot.config.get(event.getGuild()).getModeration().getStaffRole()))
+		) {
+			if (action.equals("done")) {
+				log.info("Removing reserved channel {} because it was marked as done.", channel.getAsMention());
+				channel.delete().queue();
+			} else if (action.equals("not-done")) {
+				if (event.getMessage() != null) {
+					log.info("Removing timeout check message in {} because it was marked as not-done.", channel.getAsMention());
+					event.getMessage().delete().queue();
+					channel.sendMessage("Okay, we'll keep this channel reserved for you, and check again in **" + config.getInactivityTimeoutMinutes() + "** minutes.").queue();
+				}
+			}
+		}
+	}
 }

src/main/java/com/javadiscord/javabot/events/Startup.java

@@ -5,6 +5,7 @@
 import ch.qos.logback.classic.LoggerContext;
 import com.javadiscord.javabot.Bot;
 import com.javadiscord.javabot.commands.other.Version;
+import com.javadiscord.javabot.help.HelpChannelUpdater;
 import com.javadiscord.javabot.other.Database;
 import com.javadiscord.javabot.other.Misc;
 import com.mongodb.MongoClient;
@@ -92,6 +93,10 @@ public void onReady(ReadyEvent event) {
             new Database().deleteOpenSubmissions(guild);
             new StarboardListener().updateAllSBM(guild);
             Bot.slashCommands.registerSlashCommands(guild);
+
+            // Schedule the help channel updater to run periodically for each guild.
+            var helpConfig = Bot.config.get(guild).getHelp();
+            Bot.asyncPool.scheduleAtFixedRate(new HelpChannelUpdater(event.getJDA(), helpConfig), 5, helpConfig.getUpdateIntervalSeconds(), TimeUnit.SECONDS);
         }
 
 

src/main/java/com/javadiscord/javabot/help/AlphabetNamingStrategy.java

@@ -0,0 +1,20 @@
+package com.javadiscord.javabot.help;
+
+import com.javadiscord.javabot.properties.config.guild.HelpConfig;
+import net.dv8tion.jda.api.entities.TextChannel;
+
+import java.util.List;
+import java.util.concurrent.ThreadLocalRandom;
+
+/**
+ * Naming strategy that names help channels with a random letter. Note that the
+ * chance for duplicates is quite high!
+ */
+public class AlphabetNamingStrategy implements ChannelNamingStrategy {
+	private static final String ALPHABET = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
+
+	@Override
+	public String getName(List<TextChannel> channels, HelpConfig config) {
+		return config.getOpenChannelPrefix() + "help-" + ALPHABET.charAt(ThreadLocalRandom.current().nextInt(ALPHABET.length()));
+	}
+}

src/main/java/com/javadiscord/javabot/help/AnimalNamingStrategy.java

@@ -0,0 +1,25 @@
+package com.javadiscord.javabot.help;
+
+import com.javadiscord.javabot.properties.config.guild.HelpConfig;
+import net.dv8tion.jda.api.entities.TextChannel;
+
+import java.util.List;
+import java.util.concurrent.ThreadLocalRandom;
+
+/**
+ * A naming strategy that names channels with a random animal name.
+ */
+public class AnimalNamingStrategy implements ChannelNamingStrategy {
+	private static final String[] ANIMALS = {
+			"bear", "tiger", "lion", "snake", "cheetah", "panther", "bat", "mosquito", "opossum", "raccoon", "beaver",
+			"walrus", "seal", "dolphin", "shark", "narwhal", "orca", "whale", "squid", "tuna", "nautilus", "jellyfish",
+			"seagull", "eagle", "hawk", "flamingo", "spoonbill", "puffin", "condor", "albatross", "parrot", "parakeet",
+			"rabbit", "sloth", "deer", "boar", "ferret", "dog", "cat", "marmoset", "mole", "lizard", "kangaroo"
+	};
+
+	@Override
+	public String getName(List<TextChannel> channels, HelpConfig config) {
+		String name = ANIMALS[ThreadLocalRandom.current().nextInt(ANIMALS.length)];
+		return config.getOpenChannelPrefix() + "help-" + name;
+	}
+}

src/main/java/com/javadiscord/javabot/help/ChannelNamingStrategy.java

@@ -0,0 +1,13 @@
+package com.javadiscord.javabot.help;
+
+import com.javadiscord.javabot.properties.config.guild.HelpConfig;
+import net.dv8tion.jda.api.entities.TextChannel;
+
+import java.util.List;
+
+/**
+ * A strategy to use to generate names for new help channels as they're needed.
+ */
+public interface ChannelNamingStrategy {
+	String getName(List<TextChannel> channels, HelpConfig config);
+}

src/main/java/com/javadiscord/javabot/help/HelpChannelListener.java

@@ -0,0 +1,31 @@
+package com.javadiscord.javabot.help;
+
+import com.javadiscord.javabot.Bot;
+import net.dv8tion.jda.api.entities.Category;
+import net.dv8tion.jda.api.entities.TextChannel;
+import net.dv8tion.jda.api.events.message.guild.GuildMessageReceivedEvent;
+import net.dv8tion.jda.api.hooks.ListenerAdapter;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * This listener is responsible for handling messages that are sent in one or
+ * more designated help channels.
+ */
+public class HelpChannelListener extends ListenerAdapter {
+
+	@Override
+	public void onGuildMessageReceived(@NotNull GuildMessageReceivedEvent event) {
+		if (event.getAuthor().isBot() || event.getAuthor().isSystem()) return;
+
+		var config = Bot.config.get(event.getGuild()).getHelp();
+		TextChannel channel = event.getChannel();
+		Category category = channel.getParent();
+		if (category == null || !category.equals(config.getHelpChannelCategory())) return;
+		var channelManager = new HelpChannelManager(config);
+
+		// If a message was sent in an open text channel, reserve it.
+		if (channel.getName().startsWith(config.getOpenChannelPrefix())) {
+			channelManager.reserve(channel, event.getAuthor());
+		}
+	}
+}

src/main/java/com/javadiscord/javabot/help/HelpChannelManager.java

@@ -0,0 +1,79 @@
+package com.javadiscord.javabot.help;
+
+import com.javadiscord.javabot.properties.config.guild.HelpConfig;
+import lombok.extern.slf4j.Slf4j;
+import net.dv8tion.jda.api.entities.TextChannel;
+import net.dv8tion.jda.api.entities.User;
+
+import java.util.Objects;
+import java.util.regex.Pattern;
+
+/**
+ * This manager is responsible for all the main interactions that affect the
+ * help system's channels.
+ */
+@Slf4j
+public class HelpChannelManager {
+	private final HelpConfig config;
+
+	public HelpChannelManager(HelpConfig config) {
+		this.config = config;
+	}
+
+	public boolean isOpen(TextChannel channel) {
+		return channel.getName().startsWith(config.getOpenChannelPrefix());
+	}
+
+	public boolean isReserved(TextChannel channel) {
+		return channel.getName().startsWith(config.getReservedChannelPrefix());
+	}
+
+	/**
+	 * Opens a text channel so that it is ready for a new question.
+	 */
+	public void openNew() {
+		var category = config.getHelpChannelCategory();
+		if (category == null) throw new IllegalStateException("Missing help channel category. Cannot open a new help channel.");
+		String name = this.config.getChannelNamingStrategy().getName(category.getTextChannels(), config);
+		category.createTextChannel(name).queue(channel -> {
+			channel.getManager().setPosition(0).setTopic("Ask a question here!").queue();
+			log.info("Created new help channel {}.", channel.getAsMention());
+		});
+	}
+
+	/**
+	 * Reserves a text channel for a user.
+	 * @param channel The channel to reserve.
+	 * @param reservingUser The user who is reserving the channel.
+	 */
+	public void reserve(TextChannel channel, User reservingUser) {
+		String rawChannelName = channel.getName().substring(config.getOpenChannelPrefix().length());
+		channel.getManager()
+				.setName(config.getReservedChannelPrefix() + rawChannelName)
+				.setPosition(Objects.requireNonNull(channel.getParent()).getTextChannels().size())
+				.setTopic(String.format(
+						"Reserved for %s\n(_id=%s_)",
+						reservingUser.getAsTag(),
+						reservingUser.getId()
+				)).queue();
+		log.info("Reserved channel {} for {}.", channel.getAsMention(), reservingUser.getAsTag());
+		openNew(); // Open a new channel immediately, to keep things balanced.
+	}
+
+	/**
+	 * Gets the owner of a reserved channel.
+	 * @param channel The channel to get the owner of.
+	 * @return The user who reserved the channel, or null.
+	 */
+	public User getReservedChannelOwner(TextChannel channel) {
+		var pattern = Pattern.compile("\\(_id=(\\d+)_\\)");
+		if (channel.getTopic() != null) {
+			var matcher = pattern.matcher(channel.getTopic());
+			if (matcher.find()) {
+				String id = matcher.group(1);
+				return channel.getJDA().retrieveUserById(id).complete();
+			}
+		}
+		return null;
+	}
+}

src/main/java/com/javadiscord/javabot/help/HelpChannelUpdater.java

@@ -0,0 +1,126 @@
+package com.javadiscord.javabot.help;
+
+import com.javadiscord.javabot.properties.config.guild.HelpConfig;
+import lombok.extern.slf4j.Slf4j;
+import net.dv8tion.jda.api.JDA;
+import net.dv8tion.jda.api.entities.Message;
+import net.dv8tion.jda.api.entities.TextChannel;
+import net.dv8tion.jda.api.entities.User;
+import net.dv8tion.jda.api.interactions.components.ButtonStyle;
+import net.dv8tion.jda.internal.interactions.ButtonImpl;
+
+import java.time.OffsetDateTime;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Task that updates all help channels in a particular guild.
+ */
+@Slf4j
+public class HelpChannelUpdater implements Runnable {
+	private final JDA jda;
+	private final HelpConfig config;
+	private final HelpChannelManager channelManager;
+
+	public HelpChannelUpdater(JDA jda, HelpConfig config) {
+		this.jda = jda;
+		this.config = config;
+		this.channelManager = new HelpChannelManager(config);
+	}
+
+
+	@Override
+	public void run() {
+		var category = config.getHelpChannelCategory();
+		if (category == null) throw new IllegalStateException("Missing required help channel category. Cannot update help channels.");
+		var channels = category.getTextChannels();
+		int openChannelCount = 0;
+		for (var channel : channels) {
+			if (channelManager.isReserved(channel)) {
+				this.checkReservedChannel(channel);
+			} else if (channelManager.isOpen(channel) && this.checkOpenChannel(channel)) {
+				openChannelCount++;
+			}
+		}
+		while (openChannelCount < config.getPreferredOpenChannelCount()) {
+			channelManager.openNew();
+			openChannelCount++;
+		}
+	}
+
+	/**
+	 * Performs checks on a reserved channel. This will do several things:
+	 * <ul>
+	 *     <li>
+	 *         If the most recent message in the channel is old enough, it will
+	 *         send an activity check message in the channel, asking the user to
+	 *         confirm whether they're still using it.
+	 *     </li>
+	 *     <li>
+	 *         If the most recent message is an activity check message, and it
+	 *         has stuck around long enough without any response, then the
+	 *         channel will be removed.
+	 *     </li>
+	 *     <li>
+	 *         If for some reason we can't retrieve the owner of the channel,
+	 *         like if they left the server, the channel will be removed.
+	 *     </li>
+	 * </ul>
+	 * @param channel The channel to check.
+	 */
+	private void checkReservedChannel(TextChannel channel) {
+		User owner = this.channelManager.getReservedChannelOwner(channel);
+		if (owner == null) {
+			log.info("Removing reserved channel {} because no owner could be found.", channel.getAsMention());
+			channel.delete().queue();
+			return;
+		}
+		channel.getHistory().retrievePast(1).queue(messages -> {
+			Message mostRecentMessage = messages.isEmpty() ? null : messages.get(0);
+			if (mostRecentMessage == null) {
+				log.info("Removing reserved channel {} because no recent messages could be found.", channel.getAsMention());
+				channel.delete().queue();
+				return;
+			}
+
+			// Check if the most recent message is a channel inactivity check, and check that it's old enough to surpass the remove timeout.
+			if (
+				mostRecentMessage.getAuthor().equals(this.jda.getSelfUser()) &&
+				mostRecentMessage.getContentRaw().contains("Are you finished with this channel?") &&
+				mostRecentMessage.getTimeCreated().plusMinutes(config.getRemoveTimeoutMinutes()).isBefore(OffsetDateTime.now())
+			) {
+				log.info("Removing reserved channel {} because of inactivity for {} minutes following inactive check.", channel.getAsMention(), config.getRemoveTimeoutMinutes());
+				channel.sendMessage(String.format(
+						"%s, this channel will be closed in 30 seconds due to prolonged inactivity. If your question still isn't answered, please ask again in an open channel.",
+						owner.getAsMention()
+				)).queue();
+				channel.delete().queueAfter(30, TimeUnit.SECONDS);
+				return;
+			}
+
+			// The most recent message is not an activity check, so check if it's old enough to warrant sending an activity check.
+			if (mostRecentMessage.getTimeCreated().plusMinutes(config.getInactivityTimeoutMinutes()).isBefore(OffsetDateTime.now())) {
+				log.info("Sending inactivity check to {} because of no activity after {} minutes.", channel.getAsMention(), config.getInactivityTimeoutMinutes());
+				channel.sendMessage(String.format(
+						"Hey %s, it looks like this channel is inactive. Are you finished with this channel?\n\n> _If no response is received after %d minutes, this channel will be removed._",
+						owner.getAsMention(),
+						config.getRemoveTimeoutMinutes()
+					))
+					.setActionRow(
+						new ButtonImpl("help-channel:done", "Yes, I'm done here!", ButtonStyle.SUCCESS, false, null),
+						new ButtonImpl("help-channel:not-done", "No, I'm still using it.", ButtonStyle.DANGER, false, null)
+					)
+					.queue();
+			}
+		});
+	}
+
+	private boolean checkOpenChannel(TextChannel channel) {
+		boolean isEmpty = channel.getHistoryFromBeginning(1).complete().isEmpty();
+		if (!isEmpty) {
+			log.info("Removing non-empty open channel {}.", channel.getAsMention());
+			channel.delete().complete();
+			return false;
+		}
+		return true;
+	}
+}