Added cooldown to ask command

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

@@ -126,7 +126,7 @@ public static Collection<Feature> createFeatures(JDA jda, Database database, Con
         features.add(new UnquarantineCommand(actionsStore, config));
         features.add(new WhoIsCommand());
         features.add(new WolframAlphaCommand(config));
-        features.add(new AskCommand(config, helpSystemHelper));
+        features.add(new AskCommand(config, helpSystemHelper, database));
         features.add(new ModMailCommand(jda, config));
         features.add(new HelpThreadCommand(config, helpSystemHelper));
 

application/src/main/java/org/togetherjava/tjbot/commands/help/AskCommand.java

@@ -1,9 +1,8 @@
 package org.togetherjava.tjbot.commands.help;
 
-import net.dv8tion.jda.api.entities.Guild;
-import net.dv8tion.jda.api.entities.IMentionable;
-import net.dv8tion.jda.api.entities.Member;
-import net.dv8tion.jda.api.entities.Message;
+import com.github.benmanes.caffeine.cache.Cache;
+import com.github.benmanes.caffeine.cache.Caffeine;
+import net.dv8tion.jda.api.entities.*;
 import net.dv8tion.jda.api.entities.channel.concrete.TextChannel;
 import net.dv8tion.jda.api.entities.channel.concrete.ThreadChannel;
 import net.dv8tion.jda.api.events.interaction.command.SlashCommandInteractionEvent;
@@ -19,12 +18,19 @@
 
 import org.togetherjava.tjbot.commands.CommandVisibility;
 import org.togetherjava.tjbot.commands.SlashCommandAdapter;
+import org.togetherjava.tjbot.commands.utils.MessageUtils;
 import org.togetherjava.tjbot.config.Config;
+import org.togetherjava.tjbot.db.Database;
 
+import java.time.Instant;
+import java.time.temporal.ChronoUnit;
 import java.util.Optional;
+import java.util.concurrent.TimeUnit;
 
 import static org.togetherjava.tjbot.commands.help.HelpSystemHelper.TITLE_COMPACT_LENGTH_MAX;
 import static org.togetherjava.tjbot.commands.help.HelpSystemHelper.TITLE_COMPACT_LENGTH_MIN;
+import static org.togetherjava.tjbot.commands.help.HelpThreadCommand.*;
+import static org.togetherjava.tjbot.db.generated.Tables.HELP_THREADS;
 
 /**
  * Implements the {@code /ask} command, which is the main way of asking questions. The command can
@@ -47,19 +53,27 @@
  * </pre>
  */
 public final class AskCommand extends SlashCommandAdapter {
+    private static final int COOLDOWN_DURATION_VALUE = 5;
+    private static final ChronoUnit COOLDOWN_DURATION_UNIT = ChronoUnit.MINUTES;
     private static final Logger logger = LoggerFactory.getLogger(AskCommand.class);
     public static final String COMMAND_NAME = "ask";
     private static final String TITLE_OPTION = "title";
     private static final String CATEGORY_OPTION = "category";
+    private final Cache<Long, Instant> userToLastAsk = Caffeine.newBuilder()
+        .maximumSize(1_000)
+        .expireAfterAccess(COOLDOWN_DURATION_VALUE, TimeUnit.of(COOLDOWN_DURATION_UNIT))
+        .build();
     private final HelpSystemHelper helper;
+    private final Database database;
 
     /**
      * Creates a new instance.
      *
      * @param config the config to use
      * @param helper the helper to use
+     * @param database the database to get help threads from
      */
-    public AskCommand(Config config, HelpSystemHelper helper) {
+    public AskCommand(Config config, HelpSystemHelper helper, Database database) {
         super("ask", "Ask a question - use this in the staging channel", CommandVisibility.GUILD);
 
         OptionData title =
@@ -73,10 +87,16 @@ public AskCommand(Config config, HelpSystemHelper helper) {
         getData().addOptions(title, category);
 
         this.helper = helper;
+        this.database = database;
     }
 
     @Override
     public void onSlashCommand(SlashCommandInteractionEvent event) {
+        if (isUserOnCooldown(event.getUser())) {
+            sendCooldownResponse(event);
+            return;
+        }
+
         String title = event.getOption(TITLE_OPTION).getAsString();
         String category = event.getOption(CATEGORY_OPTION).getAsString();
 
@@ -102,8 +122,44 @@ public void onSlashCommand(SlashCommandInteractionEvent event) {
         overviewChannel.createThreadChannel(name.toChannelName())
             .flatMap(threadChannel -> handleEvent(eventHook, threadChannel, author, title, category,
                     guild))
-            .queue(any -> {
-            }, e -> handleFailure(e, eventHook));
+            .queue(any -> userToLastAsk.put(event.getUser().getIdLong(), Instant.now()),
+                    e -> handleFailure(e, eventHook));
+    }
+
+    private boolean isUserOnCooldown(User user) {
+        return Optional.ofNullable(userToLastAsk.getIfPresent(user.getIdLong()))
+            .map(lastAction -> lastAction.plus(COOLDOWN_DURATION_VALUE, COOLDOWN_DURATION_UNIT))
+            .filter(Instant.now()::isBefore)
+            .isPresent();
+    }
+
+    private void sendCooldownResponse(SlashCommandInteractionEvent event) {
+        User user = event.getUser();
+        Guild guild = event.getGuild();
+
+        RestAction<String> changeTitle = mentionHelpChangeCommand(guild, CHANGE_TITLE_SUBCOMMAND);
+        RestAction<String> changeCategory =
+                mentionHelpChangeCommand(guild, CHANGE_CATEGORY_SUBCOMMAND);
+        long lastThreadByAuthorId = database
+            .read(context -> context.selectFrom(HELP_THREADS)
+                .where(HELP_THREADS.AUTHOR_ID.eq(user.getIdLong()))
+                .orderBy(HELP_THREADS.CREATED_AT.desc())
+                .limit(1)
+                .fetchOne())
+            .getChannelId();
+
+        String message =
+                """
+                        Sorry, you can only create a single help thread every %s %s. Please use your existing thread %s instead.
+                        If you made a typo or similar, you can adjust the title using the command %s and the category with %s 👌""";
+
+        RestAction.allOf(changeCategory, changeTitle)
+            .map(commandMentions -> message.formatted(COOLDOWN_DURATION_VALUE,
+                    COOLDOWN_DURATION_UNIT.name().toLowerCase(),
+                    MessageUtils.mentionChannelById(lastThreadByAuthorId), commandMentions.get(0),
+                    commandMentions.get(1)))
+            .flatMap(text -> event.reply(text).setEphemeral(true))
+            .queue();
     }
 
     private boolean handleIsValidTitle(CharSequence title, IReplyCallback event) {
@@ -173,4 +229,9 @@ private static void handleFailure(Throwable exception, InteractionHook eventHook
 
         logger.error("Attempted to create a help thread, but failed", exception);
     }
+
+    private static RestAction<String> mentionHelpChangeCommand(Guild guild, String subcommand) {
+        return MessageUtils.mentionGuildSlashCommand(guild, COMMAND_NAME, CHANGE_SUBCOMMAND_GROUP,
+                subcommand);
+    }
 }

application/src/main/java/org/togetherjava/tjbot/commands/help/HelpThreadCommand.java

@@ -41,10 +41,10 @@
 public final class HelpThreadCommand extends SlashCommandAdapter {
     private static final int COOLDOWN_DURATION_VALUE = 30;
     private static final ChronoUnit COOLDOWN_DURATION_UNIT = ChronoUnit.MINUTES;
-    private static final String CHANGE_CATEGORY_SUBCOMMAND = "category";
+    public static final String CHANGE_CATEGORY_SUBCOMMAND = "category";
     private static final String CHANGE_CATEGORY_OPTION = "category";
+    public static final String CHANGE_TITLE_SUBCOMMAND = "title";
     private static final String CHANGE_TITLE_OPTION = "title";
-    private static final String CHANGE_TITLE_SUBCOMMAND = "title";
     public static final String CHANGE_SUBCOMMAND_GROUP = "change";
     public static final String COMMAND_NAME = "help-thread";
 

application/src/main/java/org/togetherjava/tjbot/commands/utils/MessageUtils.java

@@ -141,4 +141,16 @@ public static String abbreviate(String text, int maxLength) {
         return text.substring(0, maxLength - ABBREVIATION.length()) + ABBREVIATION;
     }
 
+    /**
+     * Mentions a guild channel by its id. If the given channelId is unknown the formatted text will
+     * say `#deleted-channel` in discord.
+     *
+     * @param channelId the ID of the channel to mention
+     * @return the channel as formatted string which Discord interprets as clickable mention
+     */
+    public static String mentionChannelById(long channelId) {
+        // Clone of JDAs Channel#getAsMention, but unfortunately channel instances can not be
+        // created out of just an ID, unlike User#fromId
+        return "<#%d>".formatted(channelId);
+    }
 }