Attempt to fix commands getting unregistered

src/main/java/wtf/beatrice/hidekobot/listeners/SlashCommandListener.java

@@ -1,10 +1,17 @@
 package wtf.beatrice.hidekobot.listeners;
 
+import net.dv8tion.jda.api.entities.Message;
+import net.dv8tion.jda.api.entities.MessageChannel;
+import net.dv8tion.jda.api.entities.MessageHistory;
+import net.dv8tion.jda.api.entities.TextChannel;
 import net.dv8tion.jda.api.events.interaction.command.SlashCommandInteractionEvent;
 import net.dv8tion.jda.api.hooks.ListenerAdapter;
 import org.jetbrains.annotations.NotNull;
 import wtf.beatrice.hidekobot.utils.RandomUtil;
 
+import java.util.ArrayList;
+import java.util.List;
+
 public class SlashCommandListener extends ListenerAdapter
 {
 
@@ -14,7 +21,9 @@ public class SlashCommandListener extends ListenerAdapter
         if (event.getName().equals("ping"))
         {
             event.reply("Pong!").queue();
-        } else if (event.getName().equals("coinflip"))
+        }
+
+        else if (event.getName().equals("coinflip"))
         {
             int rand = RandomUtil.getRandomNumber(0, 1);
             String msg;
@@ -29,5 +38,34 @@ public class SlashCommandListener extends ListenerAdapter
             event.reply(msg).queue();
         }
 
+
+        else if (event.getName().equals("clear"))
+        {
+            MessageChannel channel = event.getChannel();
+
+            if(!(channel instanceof TextChannel))
+            {
+                event.reply("Sorry! I can't delete messages here.").queue();
+                return;
+            }
+
+            int deleteCount = event.getOption("amount").getAsInt();
+            if(deleteCount < 2 || deleteCount > 98)
+            {
+                event.reply("Sorry! I can't delete that amount of messages!").queue();
+                return;
+            }
+
+            event.reply("Clearing...").queue();
+
+            MessageHistory.MessageRetrieveAction action = channel.getHistoryBefore(event.getInteraction().getIdLong(), deleteCount);
+            List<Message> messagesUnmodifiable = action.complete().getRetrievedHistory();
+            List<Message> messages = new ArrayList<>(messagesUnmodifiable);
+
+            //more than 2 messages, less than 100 for this method
+            ((TextChannel) channel).deleteMessages(messages).queue();
+
+        }
+
     }
 }

src/main/java/wtf/beatrice/hidekobot/utils/SlashCommandsUtil.java

@@ -1,7 +1,10 @@
 package wtf.beatrice.hidekobot.utils;
 
 import net.dv8tion.jda.api.JDA;
+import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.interactions.commands.Command;
+import net.dv8tion.jda.api.interactions.commands.DefaultMemberPermissions;
+import net.dv8tion.jda.api.interactions.commands.OptionType;
 import net.dv8tion.jda.api.interactions.commands.build.CommandData;
 import net.dv8tion.jda.api.interactions.commands.build.Commands;
 import wtf.beatrice.hidekobot.HidekoBot;
@@ -19,12 +22,76 @@ public class SlashCommandsUtil
     {{
         add(Commands.slash("ping", "Test if the bot is responsive."));
         add(Commands.slash("coinflip", "Flip a coin and get head or tails."));
+        add(Commands.slash("clear", "Clear the current channel's chat.")
+                .addOption(OptionType.INTEGER, "amount", "The amount of messages to delete.")
+                .setDefaultPermissions(DefaultMemberPermissions.enabledFor(Permission.MESSAGE_MANAGE)));
     }};
 
     public static void updateSlashCommands()
     {
         JDA jdaInstance = HidekoBot.getAPI();
 
+        // get all the already registered commands
+        List<Command> registeredCommands = jdaInstance.retrieveCommands().complete();
+
+        boolean update = false;
+
+        // for each command that we have already registered...
+        for(Command currRegCmd : registeredCommands)
+        {
+
+            // iterate through all "recognized" commands
+            for(CommandData cmdData : allCommands)
+            {
+                // if we find the same command...
+                if(cmdData.getName().equals(currRegCmd.getName()))
+                {
+                    // quit the loop since we found it.
+                    break;
+                }
+            }
+
+            // if no match was found, we need to send an updated command list because
+            // an old command was probably removed.
+            update = true;
+        }
+
+        // if an update is not already queued...
+        if(!update)
+        {
+            // for each "recognized" valid command
+            for(CommandData currCmdData : allCommands)
+            {
+
+                // iterate through all already registered commands.
+                for(Command cmd : registeredCommands)
+                {
+                    // if this command was already registered...
+                    if(cmd.getName().equals(currCmdData.getName()))
+                    {
+                        // quit the loop since we found a match.
+                        break;
+                    }
+                }
+
+                // if no match was found, we need to send an updated command list because
+                // a new command was probably added.
+                update = true;
+            }
+        }
+        
+        logger.log("Found " + registeredCommands.size() + " commands.");
+
+        if(update)
+        {
+            // send updated command list.
+            jdaInstance.updateCommands().addCommands(allCommands).queue();
+            logger.log("Commands updated. New total: " + allCommands.size() + ".");
+        }
+
+
+
+        /*
         List<CommandData> toAdd = new ArrayList<>();
         List<Command> toDelete = new ArrayList<>();
 
@@ -91,5 +158,7 @@ public class SlashCommandsUtil
         jdaInstance.updateCommands().addCommands(toAdd).queue();
         logger.log("Registered " + toAdd.size() + " new commands.");
 
+
+         */
     }
 }