replaced single commands with /pixelblocks root command and permissions

New /pixelblocks (alias /pb) with create, give, exit and destroyall
subcommands, each gated by a permission (exit defaults to true, the
rest to op). Fixes the args[0] crash and missing UUID validation in
give, and the offline-owner NPE plus concurrent-modification risk in
destroyall (destroy now takes a force flag that skips the ownership
check for admins). Also centralizes the item id tag in
PixelBlockItem.setBlockId and drops the overridden itemName leftover.

src/main/java/eu/mhsl/minecraft/pixelblocks/Main.java

@@ -3,10 +3,8 @@ package eu.mhsl.minecraft.pixelblocks;
 import co.aikar.taskchain.BukkitTaskChainFactory;
 import co.aikar.taskchain.TaskChain;
 import co.aikar.taskchain.TaskChainFactory;
-import eu.mhsl.minecraft.pixelblocks.commands.CreatePixelBlockCommand;
+import eu.mhsl.minecraft.pixelblocks.commands.PixelBlocksCommand;
-import eu.mhsl.minecraft.pixelblocks.commands.DestroyPixelBlocksCommand;
+import org.bukkit.command.PluginCommand;
-import eu.mhsl.minecraft.pixelblocks.commands.ExitWorldCommand;
-import eu.mhsl.minecraft.pixelblocks.commands.GivePixelBlockCommand;
 import eu.mhsl.minecraft.pixelblocks.listeners.*;
 import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
 import org.bukkit.Bukkit;
@@ -82,10 +80,10 @@ public final class Main extends JavaPlugin {
             getServer().getPluginManager().registerEvents(listener, plugin);
         }
 
-        Objects.requireNonNull(getCommand("createpixelblock")).setExecutor(new CreatePixelBlockCommand());
+        PixelBlocksCommand pixelBlocksCommand = new PixelBlocksCommand();
-        Objects.requireNonNull(getCommand("givepixelblock")).setExecutor(new GivePixelBlockCommand());
+        PluginCommand rootCommand = Objects.requireNonNull(getCommand("pixelblocks"));
-        Objects.requireNonNull(getCommand("exitworld")).setExecutor(new ExitWorldCommand());
+        rootCommand.setExecutor(pixelBlocksCommand);
-        Objects.requireNonNull(getCommand("destroypixelblocks")).setExecutor(new DestroyPixelBlocksCommand());
+        rootCommand.setTabCompleter(pixelBlocksCommand);
 
         Bukkit.addRecipe(PixelBlockItem.getRecipe());
     }

src/main/java/eu/mhsl/minecraft/pixelblocks/PixelBlockItem.java

@@ -36,6 +36,12 @@ public class PixelBlockItem {
         }
     }
 
+    public static void setBlockId(@NotNull ItemStack item, @NotNull UUID id) {
+        ItemMeta meta = item.getItemMeta();
+        meta.getPersistentDataContainer().set(idProperty, PersistentDataType.STRING, id.toString());
+        item.setItemMeta(meta);
+    }
+
     public static @Nullable BlockInfo getBlockInfo(ItemStack item) {
         PersistentDataContainer container = item.getItemMeta().getPersistentDataContainer();
         if(!container.has(idProperty)) return null;
@@ -69,7 +75,6 @@ public class PixelBlockItem {
         ItemStack item = HeadUtil.getCustomTextureHead(itemTexture);
         ItemMeta meta = item.getItemMeta();
         meta.setMaxStackSize(1);
-        meta.itemName(Component.text(emptyBlockUUID.toString()));
         meta.displayName(Component.text("Leerer Pixelblock"));
         meta.lore(List.of(
             Component.text("Der erste Spieler, der den Block platziert wird zum Besitzer des Blocks."),

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/CreatePixelBlockCommand.java

@@ -1,36 +0,0 @@
-package eu.mhsl.minecraft.pixelblocks.commands;
-
-import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
-import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlockWorld;
-import eu.mhsl.minecraft.pixelblocks.utils.Direction;
-import org.bukkit.Location;
-import org.bukkit.World;
-import org.bukkit.command.Command;
-import org.bukkit.command.CommandExecutor;
-import org.bukkit.command.CommandSender;
-import org.bukkit.entity.Player;
-import org.jetbrains.annotations.NotNull;
-
-import java.util.UUID;
-
-public class CreatePixelBlockCommand implements CommandExecutor {
-    @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if(sender instanceof Player p) {
-            World playerWorld = p.getWorld();
-            if(PixelBlockWorld.getPixelBlockWorlds().contains(playerWorld)) {
-                p.sendMessage("Pixelblöcke können nicht innerhalb anderen Pixelblöcken erstellt werden.");
-                return true;
-            }
-
-            Location playerLocation = p.getLocation();
-            PixelBlock.createPixelBlock(
-                UUID.randomUUID(),
-                p.getUniqueId(),
-                playerLocation.toBlockLocation(),
-                Direction.south
-            );
-        }
-        return true;
-    }
-}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/CreateSubCommand.java

@@ -0,0 +1,32 @@
+package eu.mhsl.minecraft.pixelblocks.commands;
+
+import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
+import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlockWorld;
+import eu.mhsl.minecraft.pixelblocks.utils.Direction;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.UUID;
+
+public class CreateSubCommand extends SubCommand {
+    public CreateSubCommand() {
+        super("create", "pixelblocks.command.create", "Erstellt einen neuen Pixelblock an deiner Position.");
+    }
+
+    @Override
+    public void execute(@NotNull Player player, @NotNull String[] args) {
+        if(PixelBlockWorld.isPixelWorld(player.getWorld())) {
+            player.sendMessage(Component.text("Pixelblöcke können nicht innerhalb anderer Pixelblöcke erstellt werden.", NamedTextColor.RED));
+            return;
+        }
+
+        PixelBlock.createPixelBlock(
+            UUID.randomUUID(),
+            player.getUniqueId(),
+            player.getLocation().toBlockLocation(),
+            Direction.south
+        );
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/DestroyAllSubCommand.java

@@ -0,0 +1,23 @@
+package eu.mhsl.minecraft.pixelblocks.commands;
+
+import eu.mhsl.minecraft.pixelblocks.Main;
+import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+
+public class DestroyAllSubCommand extends SubCommand {
+    public DestroyAllSubCommand() {
+        super("destroyall", "pixelblocks.command.destroyall", "Zerstört alle Pixelblöcke auf dem Server.");
+    }
+
+    @Override
+    public void execute(@NotNull Player player, @NotNull String[] args) {
+        List<PixelBlock> blocksToDestroy = List.copyOf(Main.pixelBlocks);
+        blocksToDestroy.forEach(pixelBlock -> pixelBlock.destroy(player, true));
+        player.sendMessage(Component.text(String.format("%d Pixelblöcke werden zerstört.", blocksToDestroy.size()), NamedTextColor.GREEN));
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/DestroyPixelBlocksCommand.java

@@ -1,19 +0,0 @@
-package eu.mhsl.minecraft.pixelblocks.commands;
-
-import eu.mhsl.minecraft.pixelblocks.Main;
-import org.bukkit.Bukkit;
-import org.bukkit.command.Command;
-import org.bukkit.command.CommandExecutor;
-import org.bukkit.command.CommandSender;
-import org.bukkit.entity.Player;
-import org.jetbrains.annotations.NotNull;
-
-public class DestroyPixelBlocksCommand implements CommandExecutor {
-    @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if(sender instanceof Player p) {
-            Main.pixelBlocks.forEach(pixelBlock -> pixelBlock.destroy(Bukkit.getPlayer(pixelBlock.getOwnerUUID())));
-        }
-        return true;
-    }
-}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/ExitSubCommand.java

@@ -0,0 +1,30 @@
+package eu.mhsl.minecraft.pixelblocks.commands;
+
+import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
+import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlockWorld;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+public class ExitSubCommand extends SubCommand {
+    public ExitSubCommand() {
+        super("exit", "pixelblocks.command.exit", "Verlässt den Pixelblock, in dem du dich befindest.");
+    }
+
+    @Override
+    public void execute(@NotNull Player player, @NotNull String[] args) {
+        if(!PixelBlockWorld.isPixelWorld(player.getWorld())) {
+            player.sendMessage(Component.text("Du befindest dich nicht in einem Pixelblock.", NamedTextColor.RED));
+            return;
+        }
+
+        PixelBlock pixelBlock = PixelBlock.getPixelBlockFromBlockWorld(player.getWorld());
+        if(pixelBlock == null) {
+            player.sendMessage(Component.text("Dieser Pixelblock konnte nicht gefunden werden.", NamedTextColor.RED));
+            return;
+        }
+
+        pixelBlock.exitBlock(player);
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/ExitWorldCommand.java

@@ -1,30 +0,0 @@
-package eu.mhsl.minecraft.pixelblocks.commands;
-
-import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
-import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlockWorld;
-import org.bukkit.World;
-import org.bukkit.command.Command;
-import org.bukkit.command.CommandExecutor;
-import org.bukkit.command.CommandSender;
-import org.bukkit.entity.Player;
-import org.jetbrains.annotations.NotNull;
-
-import java.util.Objects;
-
-public class ExitWorldCommand implements CommandExecutor {
-    @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if(sender instanceof Player p) {
-            World playerWorld = p.getWorld();
-            if(PixelBlockWorld.getOtherWorlds().contains(playerWorld)) {
-                p.sendMessage("Du kannst nur Pixelblöcke verlassen.");
-                return true;
-            }
-
-            PixelBlock currentPixelBlock = PixelBlock.getPixelBlockFromBlockWorld(playerWorld);
-            Objects.requireNonNull(currentPixelBlock);
-            currentPixelBlock.exitBlock(p);
-        }
-        return true;
-    }
-}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/GivePixelBlockCommand.java

@@ -1,40 +0,0 @@
-package eu.mhsl.minecraft.pixelblocks.commands;
-
-import eu.mhsl.minecraft.pixelblocks.PixelBlockItem;
-import org.bukkit.command.Command;
-import org.bukkit.command.CommandExecutor;
-import org.bukkit.command.CommandSender;
-import org.bukkit.entity.Player;
-import org.bukkit.inventory.ItemStack;
-import org.bukkit.inventory.meta.ItemMeta;
-import org.bukkit.persistence.PersistentDataContainer;
-import org.bukkit.persistence.PersistentDataType;
-import org.jetbrains.annotations.NotNull;
-
-import java.util.Objects;
-import java.util.UUID;
-
-import static eu.mhsl.minecraft.pixelblocks.PixelBlockItem.getEmptyPixelBlock;
-
-public class GivePixelBlockCommand implements CommandExecutor {
-    @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if(sender instanceof Player p) {
-            ItemStack result = getEmptyPixelBlock();
-            ItemMeta itemMeta = result.getItemMeta();
-            PersistentDataContainer dataContainer = itemMeta.getPersistentDataContainer();
-            if(!dataContainer.has(PixelBlockItem.idProperty)) return false;
-            String currentId = dataContainer.get(PixelBlockItem.idProperty, PersistentDataType.STRING);
-            Objects.requireNonNull(currentId);
-            if(!UUID.fromString(currentId).equals(PixelBlockItem.emptyBlockUUID)) return false;
-
-            dataContainer.set(PixelBlockItem.idProperty, PersistentDataType.STRING, args[0]);
-
-            result.setItemMeta(itemMeta);
-
-
-            p.getInventory().addItem(result);
-        }
-        return true;
-    }
-}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/GiveSubCommand.java

@@ -0,0 +1,44 @@
+package eu.mhsl.minecraft.pixelblocks.commands;
+
+import eu.mhsl.minecraft.pixelblocks.PixelBlockItem;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+import java.util.UUID;
+
+public class GiveSubCommand extends SubCommand {
+    public GiveSubCommand() {
+        super("give", "pixelblocks.command.give", "Gibt dir ein Pixelblock-Item, optional mit fester UUID.");
+    }
+
+    @Override
+    public void execute(@NotNull Player player, @NotNull String[] args) {
+        UUID blockId;
+        if(args.length == 0) {
+            blockId = UUID.randomUUID();
+        } else {
+            try {
+                blockId = UUID.fromString(args[0]);
+            } catch(IllegalArgumentException e) {
+                player.sendMessage(Component.text(String.format("'%s' ist keine gültige UUID.", args[0]), NamedTextColor.RED));
+                return;
+            }
+        }
+
+        ItemStack item = PixelBlockItem.getEmptyPixelBlock();
+        PixelBlockItem.setBlockId(item, blockId);
+
+        player.getInventory().addItem(item);
+        player.sendMessage(Component.text(String.format("Pixelblock '%s' erhalten.", blockId), NamedTextColor.GREEN));
+    }
+
+    @Override
+    public @NotNull List<String> tabComplete(@NotNull Player player, @NotNull String[] args) {
+        if(args.length == 1) return List.of("<uuid>");
+        return List.of();
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/PixelBlocksCommand.java

@@ -0,0 +1,79 @@
+package eu.mhsl.minecraft.pixelblocks.commands;
+
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandExecutor;
+import org.bukkit.command.CommandSender;
+import org.bukkit.command.TabCompleter;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Optional;
+
+public class PixelBlocksCommand implements CommandExecutor, TabCompleter {
+    private final List<SubCommand> subCommands = List.of(
+        new CreateSubCommand(),
+        new GiveSubCommand(),
+        new ExitSubCommand(),
+        new DestroyAllSubCommand()
+    );
+
+    @Override
+    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
+        if(!(sender instanceof Player player)) {
+            sender.sendMessage(Component.text("Dieser Befehl kann nur von Spielern ausgeführt werden.", NamedTextColor.RED));
+            return true;
+        }
+
+        Optional<SubCommand> subCommand = args.length == 0
+            ? Optional.empty()
+            : this.subCommands.stream().filter(sub -> sub.name().equalsIgnoreCase(args[0])).findFirst();
+
+        if(subCommand.isEmpty()) {
+            this.sendUsage(player);
+            return true;
+        }
+
+        if(!player.hasPermission(subCommand.get().permission())) {
+            player.sendMessage(Component.text("Dazu hast du keine Berechtigung.", NamedTextColor.RED));
+            return true;
+        }
+
+        subCommand.get().execute(player, Arrays.copyOfRange(args, 1, args.length));
+        return true;
+    }
+
+    @Override
+    public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
+        if(!(sender instanceof Player player)) return List.of();
+
+        if(args.length == 1) {
+            return this.subCommands.stream()
+                .filter(sub -> player.hasPermission(sub.permission()))
+                .map(SubCommand::name)
+                .filter(name -> name.startsWith(args[0].toLowerCase()))
+                .toList();
+        }
+
+        return this.subCommands.stream()
+            .filter(sub -> sub.name().equalsIgnoreCase(args[0]))
+            .filter(sub -> player.hasPermission(sub.permission()))
+            .findFirst()
+            .map(sub -> sub.tabComplete(player, Arrays.copyOfRange(args, 1, args.length)))
+            .orElse(List.of());
+    }
+
+    private void sendUsage(@NotNull Player player) {
+        player.sendMessage(Component.text("PixelBlocks-Befehle:", NamedTextColor.GOLD));
+        this.subCommands.stream()
+            .filter(sub -> player.hasPermission(sub.permission()))
+            .forEach(sub -> player.sendMessage(Component.text()
+                .append(Component.text("/pixelblocks " + sub.name(), NamedTextColor.YELLOW))
+                .append(Component.text(" - " + sub.description(), NamedTextColor.GRAY))
+                .build()));
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/SubCommand.java

@@ -0,0 +1,36 @@
+package eu.mhsl.minecraft.pixelblocks.commands;
+
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+
+public abstract class SubCommand {
+    private final String name;
+    private final String permission;
+    private final String description;
+
+    protected SubCommand(@NotNull String name, @NotNull String permission, @NotNull String description) {
+        this.name = name;
+        this.permission = permission;
+        this.description = description;
+    }
+
+    public final @NotNull String name() {
+        return name;
+    }
+
+    public final @NotNull String permission() {
+        return permission;
+    }
+
+    public final @NotNull String description() {
+        return description;
+    }
+
+    public abstract void execute(@NotNull Player player, @NotNull String[] args);
+
+    public @NotNull List<String> tabComplete(@NotNull Player player, @NotNull String[] args) {
+        return List.of();
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/listeners/BreakPixelBlockListener.java

@@ -15,6 +15,6 @@ public class BreakPixelBlockListener implements Listener {
         Location blockLocation = event.getAttacked().getLocation().toBlockLocation();
         PixelBlock pixelBlock = PixelBlock.getPixelBlockFromPlacedLocation(blockLocation);
         if(pixelBlock == null) return;
-        pixelBlock.destroy(event.getPlayer());
+        pixelBlock.destroy(event.getPlayer(), false);
     }
 }

src/main/java/eu/mhsl/minecraft/pixelblocks/pixelblock/PixelBlock.java

@@ -174,10 +174,10 @@ public class PixelBlock {
             .execute();
     }
 
-    public void destroy(Player destroyedBy) {
+    public void destroy(Player destroyedBy, boolean force) {
         if(!this.isAccessible) return;
-        if(Main.configuration().onlyBreakableByOwner() && !destroyedBy.getUniqueId().equals(ownerUUID)) {
+        if(!force && Main.configuration().onlyBreakableByOwner() && !destroyedBy.getUniqueId().equals(ownerUUID)) {
-            destroyedBy.sendMessage("Dieser Pixelblock gehört nicht dir!");
+            destroyedBy.sendMessage(Component.text("Dieser Pixelblock gehört nicht dir!", NamedTextColor.RED));
             return;
         }
 

src/main/resources/plugin.yml

@@ -3,7 +3,20 @@ version: '${version}'
 main: eu.mhsl.minecraft.pixelblocks.Main
 api-version: '1.21'
 commands:
-  createpixelblock:
+  pixelblocks:
-  exitworld:
+    description: Verwaltung von Pixelblöcken
-  givepixelblock:
+    usage: /pixelblocks <create|give|exit|destroyall>
-  destroypixelblocks:
+    aliases: [pb]
+permissions:
+  pixelblocks.command.create:
+    description: Erlaubt das Erstellen eines Pixelblocks per Befehl
+    default: op
+  pixelblocks.command.give:
+    description: Erlaubt das Geben von Pixelblock-Items
+    default: op
+  pixelblocks.command.exit:
+    description: Erlaubt das Verlassen eines Pixelblocks per Befehl
+    default: true
+  pixelblocks.command.destroyall:
+    description: Erlaubt das Zerstören aller Pixelblöcke
+    default: op