Upgrade Paper to 1.21, use Brigadier command system

build.gradle

@@ -27,7 +27,7 @@ processResources {
 }
 
 dependencies {
-    compileOnly "io.papermc.paper:paper-api:1.20.4-R0.1-SNAPSHOT"
+    compileOnly("io.papermc.paper:paper-api:1.21-R0.1-SNAPSHOT")
 }
 
 jar {
@@ -36,7 +36,7 @@ jar {
 }
 
 
-def targetJavaVersion = 17
+def targetJavaVersion = 21
 java {
     def javaVersion = JavaVersion.toVersion(targetJavaVersion)
     sourceCompatibility = javaVersion

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.7-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.11-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME

src/main/java/de/shiewk/smoderation/paper/SModerationPaper.java

@@ -5,13 +5,13 @@ import de.shiewk.smoderation.paper.config.SModerationConfig;
 import de.shiewk.smoderation.paper.input.ChatInputListener;
 import de.shiewk.smoderation.paper.listener.*;
 import de.shiewk.smoderation.paper.storage.PunishmentContainer;
+import io.papermc.paper.command.brigadier.Commands;
+import io.papermc.paper.plugin.lifecycle.event.types.LifecycleEvents;
 import net.kyori.adventure.text.TextComponent;
 import net.kyori.adventure.text.format.NamedTextColor;
 import net.kyori.adventure.text.format.TextColor;
 import net.kyori.adventure.text.logger.slf4j.ComponentLogger;
 import org.bukkit.Bukkit;
-import org.bukkit.command.PluginCommand;
-import org.bukkit.command.TabExecutor;
 import org.bukkit.entity.Player;
 import org.bukkit.plugin.java.JavaPlugin;
 
@@ -34,7 +34,6 @@ public final class SModerationPaper extends JavaPlugin {
     public static final TextColor PRIMARY_COLOR = TextColor.color(212, 0, 255);
     public static final TextColor SECONDARY_COLOR = TextColor.color(52, 143, 255);
     public static final TextColor INACTIVE_COLOR = NamedTextColor.GRAY;
-    public static final TextColor FAIL_COLOR = NamedTextColor.RED;
     public static final TextComponent CHAT_PREFIX = text("SM \u00BB ").color(PRIMARY_COLOR);
 
     @Override
@@ -55,29 +54,31 @@ public final class SModerationPaper extends JavaPlugin {
         getPluginManager().registerEvents(new ChatInputListener(), this);
         getPluginManager().registerEvents(new SocialSpyListener(), this);
 
-        registerCommand("mute", new MuteCommand());
-        registerCommand("ban", new BanCommand());
-        registerCommand("kick", new KickCommand());
-        registerCommand("smod", new SModCommand());
-        registerCommand("modlogs", new ModLogsCommand());
-        registerCommand("unmute", new UnmuteCommand());
-        registerCommand("unban", new UnbanCommand());
-        registerCommand("invsee", new InvseeCommand());
-        registerCommand("enderchestsee", new EnderchestSeeCommand());
-        registerCommand("vanish", new VanishCommand());
-        registerCommand("socialspy", new SocialSpyCommand());
+        getLifecycleManager().registerEventHandler(LifecycleEvents.COMMANDS, event -> {
+            Commands commands = event.registrar();
+
+            registerCommand(commands, new KickCommand());
+            registerCommand(commands, new ModLogsCommand());
+            registerCommand(commands, new SModCommand());
+            registerCommand(commands, new InvseeCommand());
+            registerCommand(commands, new EnderchestSeeCommand());
+            registerCommand(commands, new SocialSpyCommand());
+            registerCommand(commands, new VanishCommand());
+            registerCommand(commands, new UnmuteCommand());
+            registerCommand(commands, new UnbanCommand());
+            registerCommand(commands, new MuteCommand());
+            registerCommand(commands, new BanCommand());
+        });
 
         container.load(SAVE_FILE);
     }
 
-    private void registerCommand(String label, TabExecutor executor){
-        final PluginCommand command = getCommand(label);
-        if (command != null) {
-            command.setExecutor(executor);
-            command.setTabCompleter(executor);
-        } else {
-            LOGGER.warn("Command {} failed to register: This command does not exist", label);
-        }
+    private void registerCommand(Commands commands, CommandProvider provider){
+        commands.register(
+                provider.getCommandNode(),
+                provider.getCommandDescription(),
+                provider.getAliases()
+        );
     }
 
     @Override

src/main/java/de/shiewk/smoderation/paper/command/BanCommand.java

@@ -1,124 +1,95 @@
 package de.shiewk.smoderation.paper.command;
 
+import com.mojang.brigadier.Command;
+import com.mojang.brigadier.arguments.StringArgumentType;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.tree.LiteralCommandNode;
 import de.shiewk.smoderation.paper.SModerationPaper;
+import de.shiewk.smoderation.paper.command.argument.DurationArgument;
+import de.shiewk.smoderation.paper.command.argument.PlayerUUIDArgument;
 import de.shiewk.smoderation.paper.punishments.Punishment;
-import de.shiewk.smoderation.paper.util.PlayerUtil;
-import de.shiewk.smoderation.paper.util.TimeUtil;
-import net.kyori.adventure.text.Component;
-import net.kyori.adventure.text.format.NamedTextColor;
+import de.shiewk.smoderation.paper.util.CommandUtil;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
 import org.bukkit.Bukkit;
-import org.bukkit.command.*;
 import org.bukkit.entity.Player;
-import org.bukkit.util.StringUtil;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
-import java.util.ArrayList;
+import java.util.Collection;
 import java.util.List;
 import java.util.UUID;
 
-import static net.kyori.adventure.text.Component.text;
+import static io.papermc.paper.command.brigadier.Commands.argument;
+import static io.papermc.paper.command.brigadier.Commands.literal;
+
+public final class BanCommand implements CommandProvider {
 
-public class BanCommand implements TabExecutor {
     @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length < 2){
-            return false;
-        } else {
-            UUID senderUUID;
-            if (sender instanceof ConsoleCommandSender){
-                senderUUID = PlayerUtil.UUID_CONSOLE;
-            } else if (sender instanceof Player pl){
-                senderUUID = pl.getUniqueId();
-            } else if (sender instanceof BlockCommandSender){
-                sender.sendMessage(Component.text("Blocks can't execute this command.").color(NamedTextColor.RED));
-                return true;
-            } else {
-                sender.sendMessage(Component.text("Your command sender type is unknown (%s).".formatted(sender.getClass().getName())).color(NamedTextColor.RED));
-                return true;
+    public LiteralCommandNode<CommandSourceStack> getCommandNode() {
+        return literal("ban")
+                .requires(CommandUtil.requirePermission("smod.ban"))
+                .then(argument("player", new PlayerUUIDArgument())
+                        .then(argument("duration", new DurationArgument())
+                                .executes(this::banWithoutReason)
+                                .then(argument("reason", StringArgumentType.greedyString())
+                                        .executes(this::banWithReason)
+                                )
+                        )
+                )
+                .build();
     }
-            String playerName = args[0];
-            UUID uuid = PlayerUtil.offlinePlayerUUIDByName(playerName);
-            if (senderUUID.equals(uuid)) {
-                sender.sendMessage(Component.text("You can't ban yourself.").color(NamedTextColor.RED));
-                return true;
+
+    private int banWithoutReason(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        UUID sender = CommandUtil.getSenderUUID(context.getSource());
+        UUID target = context.getArgument("player", UUID.class);
+        long duration = context.getArgument("duration", Long.class);
+        executeBan(sender, target, duration, Punishment.DEFAULT_REASON);
+        return Command.SINGLE_SUCCESS;
     }
-            if (uuid == null) {
-                sender.sendMessage(Component.text("This player is either offline or was never on this server.").color(NamedTextColor.RED));
-                return true;
-            }
-            final Player toPlayer = Bukkit.getPlayer(uuid);
-            if (toPlayer != null && toPlayer.hasPermission("smod.preventban")){
-                sender.sendMessage(text().content("This player can't be banned.").color(NamedTextColor.RED));
-                return true;
-            }
-            long duration = 0;
-            int p = 1;
-            for (int i = 1 /* start with index 1 to avoid player name */; i < args.length; i++) {
-                String arg = args[i];
-                long parsedDuration = TimeUtil.parseDurationMillisSafely(arg);
-                if (parsedDuration == -1){
-                    p = i;
-                    break;
-                } else {
-                    duration += parsedDuration;
-                }
-                if (i == args.length - 1){ p = args.length; }
+
+    private int banWithReason(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        UUID sender = CommandUtil.getSenderUUID(context.getSource());
+        UUID target = context.getArgument("player", UUID.class);
+        long duration = context.getArgument("duration", Long.class);
+        String reason = StringArgumentType.getString(context, "reason");
+        executeBan(sender, target, duration, reason);
+        return Command.SINGLE_SUCCESS;
     }
+
+    public static void executeBan(UUID sender, UUID target, long duration, String reason) throws CommandSyntaxException {
+        Player targetPlayer = Bukkit.getPlayer(target);
         if (duration == 0){
-                sender.sendMessage(Component.text("Please provide a valid duration.").color(NamedTextColor.RED));
-                return false;
+            if (targetPlayer == null){
+                CommandUtil.error("You can't ban an offline player for less than 1ms.");
+            } else {
+                KickCommand.executeKick(sender, targetPlayer, reason);
             }
-            if (duration < 0){
-                sender.sendMessage(Component.text("Please provide a duration that's longer than 0ms.").color(NamedTextColor.RED));
-                return false;
+            return;
         }
-            StringBuilder reason = new StringBuilder();
-            for (int i = p; i < args.length; i++) {
-                if (!reason.isEmpty()){
-                    reason.append(" ");
-                }
-                reason.append(args[i]);
-            }
-            final Punishment punishment = Punishment.ban(System.currentTimeMillis(), System.currentTimeMillis() + duration, senderUUID, uuid, reason.isEmpty() ? Punishment.DEFAULT_REASON : reason.toString());
+        if (sender.equals(target)) {
+            CommandUtil.error("You can't ban yourself.");
+        } else {
+            if (targetPlayer != null && targetPlayer.hasPermission("smod.preventban")){
+                CommandUtil.error("This player can't be banned.");
+            } else {
+                final Punishment punishment = Punishment.ban(
+                        System.currentTimeMillis(),
+                        System.currentTimeMillis() + duration,
+                        sender,
+                        target,
+                        reason
+                );
                 Punishment.issue(punishment, SModerationPaper.container);
-            return true;
+            }
         }
     }
 
     @Override
-    public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length < 2){
-            String toComplete = args.length > 0 ? args[0] : "";
-            ArrayList<String> names = new ArrayList<>();
-            for (Player onlinePlayer : Bukkit.getOnlinePlayers()) {
-                names.add(onlinePlayer.getName());
-            }
-            ArrayList<String> completions = new ArrayList<>();
-            StringUtil.copyPartialMatches(toComplete, names, completions);
-            return completions;
-        } else {
-            for (int i = 1; i < args.length; i++) {
-                if (TimeUtil.parseDurationMillisSafely(args[i]) == -1){
-                    try {
-                        Long.parseLong(args[i]);
-                    } catch (NumberFormatException ignored){
-                        if (i != 1){
-                            return List.of();
-                        }
-                    }
-                }
-            }
-            return List.of(
-                    "100ms",
-                    "15s", // some sample completions for duration
-                    "30min", // you can input your own ones as well
-                    "6h",
-                    "1d",
-                    "2w",
-                    "3mo",
-                    "1y"
-            );
+    public String getCommandDescription() {
+        return "Bans a player for a customizable duration.";
     }
+
+    @Override
+    public Collection<String> getAliases() {
+        return List.of("smodban");
     }
 }

src/main/java/de/shiewk/smoderation/paper/command/CommandProvider.java

@@ -0,0 +1,19 @@
+package de.shiewk.smoderation.paper.command;
+
+import com.mojang.brigadier.tree.LiteralCommandNode;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
+
+import java.util.Collection;
+import java.util.List;
+
+public interface CommandProvider {
+
+    LiteralCommandNode<CommandSourceStack> getCommandNode();
+
+    String getCommandDescription();
+
+    default Collection<String> getAliases(){
+        return List.of();
+    }
+
+}

src/main/java/de/shiewk/smoderation/paper/command/EnderchestSeeCommand.java

@@ -1,59 +1,53 @@
 package de.shiewk.smoderation.paper.command;
 
-import de.shiewk.smoderation.paper.util.PlayerUtil;
+import com.mojang.brigadier.Command;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.tree.LiteralCommandNode;
+import de.shiewk.smoderation.paper.util.CommandUtil;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
+import io.papermc.paper.command.brigadier.argument.ArgumentTypes;
 import net.kyori.adventure.text.Component;
-import org.bukkit.Bukkit;
-import org.bukkit.command.Command;
-import org.bukkit.command.CommandSender;
-import org.bukkit.command.TabExecutor;
-import org.bukkit.entity.HumanEntity;
 import org.bukkit.entity.Player;
-import org.bukkit.util.StringUtil;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
-import java.util.ArrayList;
+import java.util.Collection;
 import java.util.List;
 
 import static de.shiewk.smoderation.paper.SModerationPaper.*;
+import static io.papermc.paper.command.brigadier.Commands.argument;
+import static io.papermc.paper.command.brigadier.Commands.literal;
 
-public class EnderchestSeeCommand implements TabExecutor {
-
+public final class EnderchestSeeCommand implements CommandProvider {
 
     @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length < 1) {
-            return false;
+    public LiteralCommandNode<CommandSourceStack> getCommandNode() {
+        return literal("enderchestsee")
+                .requires(CommandUtil.requirePermission("smod.enderchestsee"))
+                .then(argument("player", ArgumentTypes.player())
+                        .executes(this::openEnderChest)
+                )
+                .build();
     }
-        if (sender instanceof HumanEntity human){
-            final Player player = PlayerUtil.findOnlinePlayer(args[0]);
-            if (player != null) {
-                human.sendMessage(CHAT_PREFIX.append(
+
+    private int openEnderChest(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        Player sender = CommandUtil.getExecutingPlayer(context.getSource());
+        Player target = CommandUtil.getPlayerSingle(context, "player");
+        sender.sendMessage(CHAT_PREFIX.append(
                 Component.text("Opening ender chest of ").color(PRIMARY_COLOR)
-                                .append(Component.text(player.getName()).color(SECONDARY_COLOR))
+                        .append(target.teamDisplayName().colorIfAbsent(SECONDARY_COLOR))
                         .append(Component.text("."))
         ));
-                human.openInventory(player.getEnderChest());
-            } else {
-                human.sendMessage(Component.text("This player is not online.").color(FAIL_COLOR));
-            }
-        } else {
-            sender.sendMessage(Component.text("Only an entity that can open inventories can execute this command!").color(FAIL_COLOR));
-        }
-        return true;
+        sender.openInventory(target.getEnderChest());
+        return Command.SINGLE_SUCCESS;
     }
 
     @Override
-    public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length > 1){
-            return List.of();
+    public String getCommandDescription() {
+        return "Views the ender chest of a player.";
     }
-        List<String> available = new ArrayList<>();
-        for (Player onlinePlayer : Bukkit.getOnlinePlayers()) {
-            available.add(onlinePlayer.getName());
-        }
-        List<String> completions = new ArrayList<>();
-        StringUtil.copyPartialMatches(args.length > 0 ? args[0] : "", available, completions);
-        return completions;
+
+    @Override
+    public Collection<String> getAliases() {
+        return List.of("ecsee");
     }
 }

src/main/java/de/shiewk/smoderation/paper/command/InvseeCommand.java

@@ -1,83 +1,81 @@
 package de.shiewk.smoderation.paper.command;
 
+import com.mojang.brigadier.Command;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.tree.LiteralCommandNode;
 import de.shiewk.smoderation.paper.inventory.InvSeeEquipmentInventory;
-import de.shiewk.smoderation.paper.util.PlayerUtil;
-import net.kyori.adventure.text.Component;
-import org.bukkit.Bukkit;
-import org.bukkit.command.Command;
-import org.bukkit.command.CommandSender;
-import org.bukkit.command.TabExecutor;
-import org.bukkit.entity.HumanEntity;
+import de.shiewk.smoderation.paper.util.CommandUtil;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
+import io.papermc.paper.command.brigadier.argument.ArgumentTypes;
 import org.bukkit.entity.Player;
-import org.bukkit.util.StringUtil;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
-import java.util.ArrayList;
+import java.util.Collection;
 import java.util.List;
 
 import static de.shiewk.smoderation.paper.SModerationPaper.*;
+import static io.papermc.paper.command.brigadier.Commands.argument;
+import static io.papermc.paper.command.brigadier.Commands.literal;
+import static net.kyori.adventure.text.Component.text;
 
-public class InvseeCommand implements TabExecutor {
-
-    private enum InvseeType {
-        INVENTORY,
-        EQUIPMENT
-    }
-
+public final class InvseeCommand implements CommandProvider {
 
     @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length < 1) {
-            return false;
+    public LiteralCommandNode<CommandSourceStack> getCommandNode() {
+        return literal("invsee")
+                .requires(CommandUtil.requirePermission("smod.invsee"))
+                .then(argument("player", ArgumentTypes.player())
+                        .executes(this::invseeInventory)
+                        .then(literal("inventory")
+                                .executes(this::invseeInventory)
+                        )
+                        .then(literal("armor")
+                                .executes(this::invseeEquipment)
+                        )
+                        .then(literal("equipment")
+                                .executes(this::invseeEquipment)
+                        )
+                )
+                .build();
     }
-        final InvseeType type;
-        if (args.length > 1){
-            switch (args[1].toLowerCase()){
-                case "armor", "equipment" -> type = InvseeType.EQUIPMENT;
-                default -> type = InvseeType.INVENTORY;
+
+    private int invseeInventory(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        Player sender = CommandUtil.getExecutingPlayer(context.getSource());
+        Player target = CommandUtil.getPlayerSingle(context, "player");
+        if (sender.equals(target)){
+            CommandUtil.error("You can't open your own inventory.");
         }
-        } else {
-            type = InvseeType.INVENTORY;
-        }
-        if (sender instanceof HumanEntity human){
-            final Player player = PlayerUtil.findOnlinePlayer(args[0]);
-            if (player != null) {
-                if (human.getUniqueId().equals(player.getUniqueId()) && type != InvseeType.EQUIPMENT){
-                    human.sendMessage(Component.text("You can't open your own inventory.").color(FAIL_COLOR));
-                } else {
-                    human.sendMessage(CHAT_PREFIX.append(
-                            Component.text("Opening inventory of ").color(PRIMARY_COLOR)
-                                    .append(Component.text(player.getName()).color(SECONDARY_COLOR))
-                                    .append(Component.text("."))
+        sender.sendMessage(CHAT_PREFIX.append(
+                text("Opening inventory of ").color(PRIMARY_COLOR)
+                        .append(target.teamDisplayName().colorIfAbsent(SECONDARY_COLOR))
+                        .append(text("."))
         ));
-                    switch (type){
-                        case INVENTORY -> human.openInventory(player.getInventory());
-                        case EQUIPMENT -> new InvSeeEquipmentInventory(human, player).open();
+        sender.openInventory(target.getInventory());
+        return Command.SINGLE_SUCCESS;
     }
+
+    private int invseeEquipment(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        Player sender = CommandUtil.getExecutingPlayer(context.getSource());
+        Player target = CommandUtil.getPlayerSingle(context, "player");
+        if (sender.equals(target)){
+            CommandUtil.error("You can't open your own inventory.");
         }
-            } else {
-                human.sendMessage(Component.text("This player is not online.").color(FAIL_COLOR));
-            }
-        } else {
-            sender.sendMessage(Component.text("Only an entity that can open inventories can execute this command!").color(FAIL_COLOR));
-        }
-        return true;
+        sender.sendMessage(CHAT_PREFIX.append(
+                text("Opening inventory of ").color(PRIMARY_COLOR)
+                        .append(target.teamDisplayName().colorIfAbsent(SECONDARY_COLOR))
+                        .append(text("."))
+        ));
+        new InvSeeEquipmentInventory(sender, target).open();
+        return Command.SINGLE_SUCCESS;
     }
 
     @Override
-    public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length > 2){
-            return List.of();
-        } else if (args.length > 1){
-            return List.of("armor", "equipment", "inventory");
+    public String getCommandDescription() {
+        return "Views the inventory of another player.";
     }
-        List<String> available = new ArrayList<>();
-        for (Player onlinePlayer : Bukkit.getOnlinePlayers()) {
-            available.add(onlinePlayer.getName());
-        }
-        List<String> completions = new ArrayList<>();
-        StringUtil.copyPartialMatches(args.length > 0 ? args[0] : "", available, completions);
-        return completions;
+
+    @Override
+    public Collection<String> getAliases() {
+        return List.of("sinvsee", "smodinvsee", "invs");
     }
 }

src/main/java/de/shiewk/smoderation/paper/command/KickCommand.java

@@ -1,81 +1,77 @@
 package de.shiewk.smoderation.paper.command;
 
+import com.mojang.brigadier.Command;
+import com.mojang.brigadier.arguments.StringArgumentType;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.tree.LiteralCommandNode;
 import de.shiewk.smoderation.paper.SModerationPaper;
 import de.shiewk.smoderation.paper.punishments.Punishment;
-import de.shiewk.smoderation.paper.util.PlayerUtil;
-import net.kyori.adventure.text.Component;
-import net.kyori.adventure.text.format.NamedTextColor;
-import org.bukkit.Bukkit;
-import org.bukkit.command.*;
+import de.shiewk.smoderation.paper.util.CommandUtil;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
+import io.papermc.paper.command.brigadier.argument.ArgumentTypes;
 import org.bukkit.entity.Player;
-import org.bukkit.util.StringUtil;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
-import java.util.ArrayList;
+import java.util.Collection;
 import java.util.List;
 import java.util.UUID;
 
-import static net.kyori.adventure.text.Component.text;
+import static io.papermc.paper.command.brigadier.Commands.argument;
+import static io.papermc.paper.command.brigadier.Commands.literal;
+
+public final class KickCommand implements CommandProvider {
 
-public class KickCommand implements TabExecutor {
     @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length < 1){
-            return false;
-        } else {
-            UUID senderUUID;
-            if (sender instanceof ConsoleCommandSender){
-                senderUUID = PlayerUtil.UUID_CONSOLE;
-            } else if (sender instanceof Player pl){
-                senderUUID = pl.getUniqueId();
-            } else if (sender instanceof BlockCommandSender){
-                sender.sendMessage(Component.text("Blocks can't execute this command.").color(NamedTextColor.RED));
-                return true;
-            } else {
-                sender.sendMessage(Component.text("Your command sender type is unknown (%s).".formatted(sender.getClass().getName())).color(NamedTextColor.RED));
-                return true;
+    public LiteralCommandNode<CommandSourceStack> getCommandNode() {
+        return literal("kick")
+                .requires(CommandUtil.requirePermission("smod.kick"))
+                .then(argument("player", ArgumentTypes.player())
+                        .executes(this::kickWithoutReason)
+                        .then(argument("reason", StringArgumentType.greedyString())
+                                .executes(this::kickWithReason)
+                        )
+                )
+                .build();
     }
-            String playerName = args[0];
-            Player player = Bukkit.getPlayer(playerName);
-            if (player == null) {
-                sender.sendMessage(Component.text("This player is not online.").color(NamedTextColor.RED));
-                return true;
+
+    private int kickWithReason(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        UUID sender = CommandUtil.getSenderUUID(context.getSource());
+        Player target = CommandUtil.getPlayerSingle(context, "player");
+        String reason = StringArgumentType.getString(context, "reason");
+        executeKick(sender, target, reason);
+        return Command.SINGLE_SUCCESS;
     }
-            UUID uuid = player.getUniqueId();
-            if (senderUUID.equals(uuid)) {
-                sender.sendMessage(Component.text("You can't kick yourself.").color(NamedTextColor.RED));
-                return true;
+
+    private int kickWithoutReason(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        UUID sender = CommandUtil.getSenderUUID(context.getSource());
+        Player target = CommandUtil.getPlayerSingle(context, "player");
+        executeKick(sender, target, Punishment.DEFAULT_REASON);
+        return Command.SINGLE_SUCCESS;
     }
-            if (player.hasPermission("smod.preventkick")){
-                sender.sendMessage(text().content("This player can't be kicked.").color(NamedTextColor.RED));
-                return true;
+
+    public static void executeKick(UUID sender, Player target, String reason) throws CommandSyntaxException {
+        UUID targetId = target.getUniqueId();
+        if (sender.equals(targetId)) {
+            CommandUtil.error("You can't kick yourself.");
+        } else if (target.hasPermission("smod.preventkick")){
+            CommandUtil.error("This player can't be kicked.");
         }
-            StringBuilder reason = new StringBuilder();
-            for (int i = 1; i < args.length; i++) {
-                if (!reason.isEmpty()){
-                    reason.append(" ");
-                }
-                reason.append(args[i]);
-            }
-            final Punishment punishment = Punishment.kick(System.currentTimeMillis(), senderUUID, uuid, reason.isEmpty() ? Punishment.DEFAULT_REASON : reason.toString());
+        final Punishment punishment = Punishment.kick(
+                System.currentTimeMillis(),
+                sender,
+                targetId,
+                reason
+        );
         Punishment.issue(punishment, SModerationPaper.container);
-            return true;
-        }
     }
 
     @Override
-    public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length < 2){
-            String toComplete = args.length > 0 ? args[0] : "";
-            ArrayList<String> names = new ArrayList<>();
-            for (Player onlinePlayer : Bukkit.getOnlinePlayers()) {
-                names.add(onlinePlayer.getName());
+    public String getCommandDescription() {
+        return "Kicks a player";
     }
-            ArrayList<String> completions = new ArrayList<>();
-            StringUtil.copyPartialMatches(toComplete, names, completions);
-            return completions;
-        }
-        return List.of();
+
+    @Override
+    public Collection<String> getAliases() {
+        return List.of("smodkick");
     }
 }

src/main/java/de/shiewk/smoderation/paper/command/ModLogsCommand.java

@@ -1,51 +1,47 @@
 package de.shiewk.smoderation.paper.command;
 
+import com.mojang.brigadier.Command;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.tree.LiteralCommandNode;
 import de.shiewk.smoderation.paper.SModerationPaper;
+import de.shiewk.smoderation.paper.command.argument.PlayerUUIDArgument;
 import de.shiewk.smoderation.paper.punishments.Punishment;
 import de.shiewk.smoderation.paper.punishments.PunishmentType;
+import de.shiewk.smoderation.paper.util.CommandUtil;
 import de.shiewk.smoderation.paper.util.PlayerUtil;
 import de.shiewk.smoderation.paper.util.TimeUtil;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
 import net.kyori.adventure.text.Component;
-import net.kyori.adventure.text.format.NamedTextColor;
-import org.bukkit.Bukkit;
-import org.bukkit.command.Command;
 import org.bukkit.command.CommandSender;
-import org.bukkit.command.TabExecutor;
-import org.bukkit.entity.Player;
-import org.bukkit.util.StringUtil;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
-import java.util.ArrayList;
+import java.util.Collection;
 import java.util.List;
 import java.util.UUID;
 
 import static de.shiewk.smoderation.paper.SModerationPaper.*;
+import static io.papermc.paper.command.brigadier.Commands.argument;
+import static io.papermc.paper.command.brigadier.Commands.literal;
+
+public final class ModLogsCommand implements CommandProvider {
 
-public class ModLogsCommand implements TabExecutor {
     @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length < 1){
-            return false;
-        } else {
-            String playername = args[0];
-            String name;
-            UUID uuid;
-            try {
-                uuid = UUID.fromString(playername);
-            } catch (IllegalArgumentException ignored){
-                uuid = PlayerUtil.offlinePlayerUUIDByName(playername);
+    public LiteralCommandNode<CommandSourceStack> getCommandNode() {
+        return literal("modlogs")
+                .requires(CommandUtil.requirePermission("smod.logs"))
+                .then(argument("player", new PlayerUUIDArgument())
+                        .executes(this::showModLogs)
+                )
+                .build();
     }
-            if (uuid == null){
-                sender.sendMessage(Component.text("This player was not found. Try running /%s with an UUID instead.".formatted(label)).color(NamedTextColor.RED));
-                return true;
-            }
-            name = PlayerUtil.offlinePlayerName(uuid);
+
+    private int showModLogs(CommandContext<CommandSourceStack> context) {
+        CommandSender sender = context.getSource().getSender();
+        UUID uuid = context.getArgument("player", UUID.class);
+        String name = PlayerUtil.offlinePlayerName(uuid);
         sender.sendMessage(CHAT_PREFIX.append(Component.text("Player ").color(PRIMARY_COLOR)
                 .append(Component.text(name).color(SECONDARY_COLOR))
                 .append(Component.text(" (%s)".formatted(uuid)).color(INACTIVE_COLOR))));
-            UUID finalUuid = uuid;
-            final List<Punishment> punishments = SModerationPaper.container.findAll(p -> p.to.equals(finalUuid) && p.isActive());
+        final List<Punishment> punishments = SModerationPaper.container.findAll(p -> p.to.equals(uuid) && p.isActive());
         for (Punishment punishment : punishments) {
             sender.sendMessage(Component.text("- is currently ").color(PRIMARY_COLOR)
                     .append(Component.text(punishment.type == PunishmentType.BAN ? "banned" : "muted").color(SECONDARY_COLOR))
@@ -58,22 +54,16 @@ public class ModLogsCommand implements TabExecutor {
         if (punishments.isEmpty()){
             sender.sendMessage(Component.text("- has no punishments.").color(PRIMARY_COLOR));
         }
-            return true;
-        }
+        return Command.SINGLE_SUCCESS;
     }
 
     @Override
-    public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length > 1){
-            return List.of();
+    public String getCommandDescription() {
+        return "Views all current punishments of a player.";
     }
-        String search = args.length > 0 ? args[0] : "";
-        List<String> playernames = new ArrayList<>();
-        for (Player onlinePlayer : Bukkit.getOnlinePlayers()) {
-            playernames.add(onlinePlayer.getName());
-        }
-        List<String> completions = new ArrayList<>();
-        StringUtil.copyPartialMatches(search, playernames, completions);
-        return completions;
+
+    @Override
+    public Collection<String> getAliases() {
+        return List.of("logs", "seen", "smodlogs");
     }
 }

src/main/java/de/shiewk/smoderation/paper/command/MuteCommand.java

@@ -1,123 +1,87 @@
 package de.shiewk.smoderation.paper.command;
 
+import com.mojang.brigadier.Command;
+import com.mojang.brigadier.arguments.StringArgumentType;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.tree.LiteralCommandNode;
 import de.shiewk.smoderation.paper.SModerationPaper;
+import de.shiewk.smoderation.paper.command.argument.DurationArgument;
+import de.shiewk.smoderation.paper.command.argument.PlayerUUIDArgument;
 import de.shiewk.smoderation.paper.punishments.Punishment;
-import de.shiewk.smoderation.paper.util.PlayerUtil;
-import de.shiewk.smoderation.paper.util.TimeUtil;
-import net.kyori.adventure.text.format.NamedTextColor;
+import de.shiewk.smoderation.paper.util.CommandUtil;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
 import org.bukkit.Bukkit;
-import org.bukkit.command.*;
 import org.bukkit.entity.Player;
-import org.bukkit.util.StringUtil;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
-import java.util.ArrayList;
+import java.util.Collection;
 import java.util.List;
 import java.util.UUID;
 
-import static net.kyori.adventure.text.Component.text;
+import static io.papermc.paper.command.brigadier.Commands.argument;
+import static io.papermc.paper.command.brigadier.Commands.literal;
 
-public class MuteCommand implements TabExecutor {
-    @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length < 2){
-            return false;
-        } else {
-            UUID senderUUID;
-            if (sender instanceof ConsoleCommandSender){
-                senderUUID = PlayerUtil.UUID_CONSOLE;
-            } else if (sender instanceof Player pl){
-                senderUUID = pl.getUniqueId();
-            } else if (sender instanceof BlockCommandSender){
-                sender.sendMessage(text("Blocks can't execute this command.").color(NamedTextColor.RED));
-                return true;
-            } else {
-                sender.sendMessage(text("Your command sender type is unknown (%s).".formatted(sender.getClass().getName())).color(NamedTextColor.RED));
-                return true;
-            }
-            String playerName = args[0];
-            UUID uuid = PlayerUtil.offlinePlayerUUIDByName(playerName);
-            if (senderUUID.equals(uuid)) {
-                sender.sendMessage(text("You can't mute yourself.").color(NamedTextColor.RED));
-                return true;
-            }
-            if (uuid == null) {
-                sender.sendMessage(text("This player is either offline or was never on this server.").color(NamedTextColor.RED));
-                return true;
-            }
-            final Player toPlayer = Bukkit.getPlayer(uuid);
-            if (toPlayer != null && toPlayer.hasPermission("smod.preventmute")){
-                sender.sendMessage(text().content("This player can't be muted.").color(NamedTextColor.RED));
-                return true;
-            }
-            long duration = 0;
-            int p = 1;
-            for (int i = 1 /* start with index 1 to avoid player name */; i < args.length; i++) {
-                String arg = args[i];
-                long parsedDuration = TimeUtil.parseDurationMillisSafely(arg);
-                if (parsedDuration == -1){
-                    p = i;
-                    break;
-                } else {
-                    duration += parsedDuration;
-                }
-                if (i == args.length - 1){ p = args.length; }
-            }
-            if (duration == 0){
-                sender.sendMessage(text("Please provide a valid duration.").color(NamedTextColor.RED));
-                return false;
-            }
-            if (duration < 0){
-                sender.sendMessage(text("Please provide a duration that's longer than 0ms.").color(NamedTextColor.RED));
-                return false;
-            }
-            StringBuilder reason = new StringBuilder();
-            for (int i = p; i < args.length; i++) {
-                if (!reason.isEmpty()){
-                    reason.append(" ");
-                }
-                reason.append(args[i]);
-            }
-            final Punishment punishment = Punishment.mute(System.currentTimeMillis(), System.currentTimeMillis() + duration, senderUUID, uuid, reason.isEmpty() ? Punishment.DEFAULT_REASON : reason.toString());
-            Punishment.issue(punishment, SModerationPaper.container);
-            return true;
-        }
-    }
+public final class MuteCommand implements CommandProvider {
 
     @Override
-    public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length < 2){
-            String toComplete = args.length > 0 ? args[0] : "";
-            ArrayList<String> names = new ArrayList<>();
-            for (Player onlinePlayer : Bukkit.getOnlinePlayers()) {
-                names.add(onlinePlayer.getName());
+    public LiteralCommandNode<CommandSourceStack> getCommandNode() {
+        return literal("mute")
+                .requires(CommandUtil.requirePermission("smod.mute"))
+                .then(argument("player", new PlayerUUIDArgument())
+                        .then(argument("duration", new DurationArgument())
+                                .executes(this::muteWithoutReason)
+                                .then(argument("reason", StringArgumentType.greedyString())
+                                        .executes(this::muteWithReason)
+                                )
+                        )
+                )
+                .build();
     }
-            ArrayList<String> completions = new ArrayList<>();
-            StringUtil.copyPartialMatches(toComplete, names, completions);
-            return completions;
+
+    private int muteWithoutReason(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        UUID sender = CommandUtil.getSenderUUID(context.getSource());
+        UUID target = context.getArgument("player", UUID.class);
+        long duration = context.getArgument("duration", Long.class);
+        executeMute(sender, target, duration, Punishment.DEFAULT_REASON);
+        return Command.SINGLE_SUCCESS;
+    }
+
+    private int muteWithReason(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        UUID sender = CommandUtil.getSenderUUID(context.getSource());
+        UUID target = context.getArgument("player", UUID.class);
+        long duration = context.getArgument("duration", Long.class);
+        String reason = StringArgumentType.getString(context, "reason");
+        executeMute(sender, target, duration, reason);
+        return Command.SINGLE_SUCCESS;
+    }
+
+    public static void executeMute(UUID sender, UUID target, long duration, String reason) throws CommandSyntaxException {
+        if (sender.equals(target)) {
+            CommandUtil.error("You can't mute yourself.");
         } else {
-            for (int i = 1; i < args.length; i++) {
-                if (TimeUtil.parseDurationMillisSafely(args[i]) == -1){
-                    try {
-                        Long.parseLong(args[i]);
-                    } catch (NumberFormatException ignored){
-                        if (i != 1){
-                            return List.of();
-                        }
-                    }
-                }
-            }
-            return List.of(
-                    "100ms",
-                    "15s", // some sample completions for duration
-                    "30min", // you can input your own ones as well
-                    "6h",
-                    "1d",
-                    "2w",
-                    "3mo",
-                    "1y"
+            Player targetPlayer = Bukkit.getPlayer(target);
+            if (targetPlayer != null && targetPlayer.hasPermission("smod.preventmute")){
+                CommandUtil.error("This player can't be muted.");
+            } else {
+                final Punishment punishment = Punishment.mute(
+                        System.currentTimeMillis(),
+                        System.currentTimeMillis() + duration,
+                        sender,
+                        target,
+                        reason
                 );
+                Punishment.issue(punishment, SModerationPaper.container);
             }
         }
+    }
+
+    @Override
+    public String getCommandDescription() {
+        return "Mutes a player for a customizable duration.";
+    }
+
+    @Override
+    public Collection<String> getAliases() {
+        return List.of("smodmute");
+    }
 }

src/main/java/de/shiewk/smoderation/paper/command/SModCommand.java

@@ -1,27 +1,43 @@
 package de.shiewk.smoderation.paper.command;
 
+import com.mojang.brigadier.Command;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.tree.LiteralCommandNode;
 import de.shiewk.smoderation.paper.SModerationPaper;
 import de.shiewk.smoderation.paper.inventory.SModMenu;
-import org.bukkit.command.Command;
-import org.bukkit.command.CommandSender;
-import org.bukkit.command.TabExecutor;
+import de.shiewk.smoderation.paper.util.CommandUtil;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
 import org.bukkit.entity.Player;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
+import java.util.Collection;
 import java.util.List;
 
-public class SModCommand implements TabExecutor {
+import static io.papermc.paper.command.brigadier.Commands.literal;
+
+public final class SModCommand implements CommandProvider {
+
     @Override
-    public boolean onCommand(@NotNull CommandSender commandSender, @NotNull Command command, @NotNull String s, @NotNull String[] strings) {
-        if (commandSender instanceof Player player){
-            new SModMenu(player, SModerationPaper.container).open();
+    public LiteralCommandNode<CommandSourceStack> getCommandNode() {
+        return literal("smod")
+                .requires(CommandUtil.requirePermission("smod.menu"))
+                .executes(this::openMenu)
+                .build();
     }
-        return true;
+
+    private int openMenu(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        Player player = CommandUtil.getExecutingPlayer(context.getSource());
+        new SModMenu(player, SModerationPaper.container).open();
+        return Command.SINGLE_SUCCESS;
     }
 
     @Override
-    public @Nullable List<String> onTabComplete(@NotNull CommandSender commandSender, @NotNull Command command, @NotNull String s, @NotNull String[] strings) {
-        return List.of();
+    public String getCommandDescription() {
+        return "Shows the SModeration menu.";
+    }
+
+    @Override
+    public Collection<String> getAliases() {
+        return List.of("smodmenu", "smoderation");
     }
 }

src/main/java/de/shiewk/smoderation/paper/command/SocialSpyCommand.java

@@ -1,32 +1,49 @@
 package de.shiewk.smoderation.paper.command;
 
+import com.mojang.brigadier.Command;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.tree.LiteralCommandNode;
 import de.shiewk.smoderation.paper.listener.SocialSpyListener;
+import de.shiewk.smoderation.paper.util.CommandUtil;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
 import net.kyori.adventure.text.format.NamedTextColor;
-import org.bukkit.command.Command;
 import org.bukkit.command.CommandSender;
-import org.bukkit.command.TabExecutor;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
+import java.util.Collection;
 import java.util.List;
 
 import static de.shiewk.smoderation.paper.SModerationPaper.CHAT_PREFIX;
+import static io.papermc.paper.command.brigadier.Commands.literal;
 import static net.kyori.adventure.text.Component.text;
 
-public class SocialSpyCommand implements TabExecutor {
+public final class SocialSpyCommand implements CommandProvider {
+
     @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
+    public LiteralCommandNode<CommandSourceStack> getCommandNode() {
+        return literal("socialspy")
+                .requires(CommandUtil.requirePermission("smod.socialspy"))
+                .executes(this::toggleSocialSpy)
+                .build();
+    }
+
+    private int toggleSocialSpy(CommandContext<CommandSourceStack> context) {
+        CommandSender sender = context.getSource().getSender();
         final boolean enabled = SocialSpyListener.toggle(sender);
         sender.sendMessage(CHAT_PREFIX.append(text("SocialSpy ").append(
                 enabled ?
                         text("enabled").color(NamedTextColor.GREEN) :
                         text("disabled").color(NamedTextColor.RED)
         ).append(text("."))));
-        return true;
+        return Command.SINGLE_SUCCESS;
     }
 
     @Override
-    public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        return List.of();
+    public String getCommandDescription() {
+        return "Enables socialspy mode (you can see private messages of other players)";
+    }
+
+    @Override
+    public Collection<String> getAliases() {
+        return List.of("smodsocialspy");
     }
 }

src/main/java/de/shiewk/smoderation/paper/command/UnbanCommand.java

@@ -1,64 +1,56 @@
 package de.shiewk.smoderation.paper.command;
 
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.tree.LiteralCommandNode;
 import de.shiewk.smoderation.paper.SModerationPaper;
+import de.shiewk.smoderation.paper.command.argument.PlayerUUIDArgument;
 import de.shiewk.smoderation.paper.punishments.Punishment;
 import de.shiewk.smoderation.paper.punishments.PunishmentType;
-import de.shiewk.smoderation.paper.util.PlayerUtil;
-import net.kyori.adventure.text.Component;
-import net.kyori.adventure.text.format.NamedTextColor;
-import org.bukkit.command.*;
-import org.bukkit.entity.Player;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
+import de.shiewk.smoderation.paper.util.CommandUtil;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
 
+import java.util.Collection;
 import java.util.List;
 import java.util.UUID;
 
-public class UnbanCommand implements TabExecutor {
+import static io.papermc.paper.command.brigadier.Commands.argument;
+import static io.papermc.paper.command.brigadier.Commands.literal;
+
+public final class UnbanCommand implements CommandProvider {
+
     @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length < 1){
-            return false;
-        } else {
-
-            UUID senderUUID;
-            if (sender instanceof ConsoleCommandSender){
-                senderUUID = PlayerUtil.UUID_CONSOLE;
-            } else if (sender instanceof Player pl){
-                senderUUID = pl.getUniqueId();
-            } else if (sender instanceof BlockCommandSender){
-                sender.sendMessage(Component.text("Blocks can't execute this command.").color(NamedTextColor.RED));
-                return true;
-            } else {
-                sender.sendMessage(Component.text("Your command sender type is unknown (%s).".formatted(sender.getClass().getName())).color(NamedTextColor.RED));
-                return true;
+    public LiteralCommandNode<CommandSourceStack> getCommandNode() {
+        return literal("unban")
+                .requires(CommandUtil.requirePermission("smod.unban"))
+                .then(argument("player", new PlayerUUIDArgument())
+                        .executes(this::unbanPlayer)
+                )
+                .build();
     }
 
-            String nameArg = args[0];
-            UUID uuid;
-            try {
-                uuid = UUID.fromString(nameArg);
-            } catch (IllegalArgumentException ignored){
-                uuid = PlayerUtil.offlinePlayerUUIDByName(nameArg);
-            }
-            if (uuid == null){
-                sender.sendMessage(Component.text("This player was not found. Try running /%s with an UUID instead.".formatted(label)).color(NamedTextColor.RED));
-                return true;
-            }
-            UUID finalUuid = uuid;
-            final Punishment punishment = SModerationPaper.container.find(p -> p.to.equals(finalUuid) && p.isActive() && p.type == PunishmentType.BAN);
+    private int unbanPlayer(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        UUID senderUUID = CommandUtil.getSenderUUID(context.getSource());
+        UUID target = context.getArgument("player", UUID.class);
+        final Punishment punishment = SModerationPaper.container.find(
+                p -> p.to.equals(target) && p.isActive() && p.type == PunishmentType.BAN
+        );
         if (punishment != null) {
             punishment.undo(senderUUID);
             punishment.broadcastUndo(SModerationPaper.container);
         } else {
-                sender.sendMessage(Component.text("This player is not banned.").color(NamedTextColor.RED));
-            }
-            return true;
+            CommandUtil.error("This player is not banned.");
         }
+        return com.mojang.brigadier.Command.SINGLE_SUCCESS;
     }
 
     @Override
-    public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        return List.of();
+    public String getCommandDescription() {
+        return "Unbans a banned player.";
+    }
+
+    @Override
+    public Collection<String> getAliases() {
+        return List.of("smodunban");
     }
 }

src/main/java/de/shiewk/smoderation/paper/command/UnmuteCommand.java

@@ -1,64 +1,57 @@
 package de.shiewk.smoderation.paper.command;
 
+import com.mojang.brigadier.Command;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.tree.LiteralCommandNode;
 import de.shiewk.smoderation.paper.SModerationPaper;
+import de.shiewk.smoderation.paper.command.argument.PlayerUUIDArgument;
 import de.shiewk.smoderation.paper.punishments.Punishment;
 import de.shiewk.smoderation.paper.punishments.PunishmentType;
-import de.shiewk.smoderation.paper.util.PlayerUtil;
-import net.kyori.adventure.text.Component;
-import net.kyori.adventure.text.format.NamedTextColor;
-import org.bukkit.command.*;
-import org.bukkit.entity.Player;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
+import de.shiewk.smoderation.paper.util.CommandUtil;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
 
+import java.util.Collection;
 import java.util.List;
 import java.util.UUID;
 
-public class UnmuteCommand implements TabExecutor {
+import static io.papermc.paper.command.brigadier.Commands.argument;
+import static io.papermc.paper.command.brigadier.Commands.literal;
+
+public final class UnmuteCommand implements CommandProvider {
+
     @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length < 1){
-            return false;
-        } else {
-
-            UUID senderUUID;
-            if (sender instanceof ConsoleCommandSender){
-                senderUUID = PlayerUtil.UUID_CONSOLE;
-            } else if (sender instanceof Player pl){
-                senderUUID = pl.getUniqueId();
-            } else if (sender instanceof BlockCommandSender){
-                sender.sendMessage(Component.text("Blocks can't execute this command.").color(NamedTextColor.RED));
-                return true;
-            } else {
-                sender.sendMessage(Component.text("Your command sender type is unknown (%s).".formatted(sender.getClass().getName())).color(NamedTextColor.RED));
-                return true;
+    public LiteralCommandNode<CommandSourceStack> getCommandNode() {
+        return literal("unmute")
+                .requires(CommandUtil.requirePermission("smod.unmute"))
+                .then(argument("player", new PlayerUUIDArgument())
+                        .executes(this::unmutePlayer)
+                )
+                .build();
     }
 
-            String nameArg = args[0];
-            UUID uuid;
-            try {
-                uuid = UUID.fromString(nameArg);
-            } catch (IllegalArgumentException ignored){
-                uuid = PlayerUtil.offlinePlayerUUIDByName(nameArg);
-            }
-            if (uuid == null){
-                sender.sendMessage(Component.text("This player was not found. Try running /%s with an UUID instead.".formatted(label)).color(NamedTextColor.RED));
-                return true;
-            }
-            UUID finalUuid = uuid;
-            final Punishment punishment = SModerationPaper.container.find(p -> p.to.equals(finalUuid) && p.isActive() && p.type == PunishmentType.MUTE);
+    private int unmutePlayer(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        UUID senderUUID = CommandUtil.getSenderUUID(context.getSource());
+        UUID target = context.getArgument("player", UUID.class);
+        final Punishment punishment = SModerationPaper.container.find(
+                p -> p.to.equals(target) && p.isActive() && p.type == PunishmentType.MUTE
+        );
         if (punishment != null) {
             punishment.undo(senderUUID);
             punishment.broadcastUndo(SModerationPaper.container);
         } else {
-                sender.sendMessage(Component.text("This player is not muted.").color(NamedTextColor.RED));
-            }
-            return true;
+            CommandUtil.error("This player is not muted.");
         }
+        return Command.SINGLE_SUCCESS;
     }
 
     @Override
-    public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        return List.of();
+    public String getCommandDescription() {
+        return "Unmutes a muted player.";
+    }
+
+    @Override
+    public Collection<String> getAliases() {
+        return List.of("smodunmute");
     }
 }

src/main/java/de/shiewk/smoderation/paper/command/VanishCommand.java

@@ -1,66 +1,83 @@
 package de.shiewk.smoderation.paper.command;
 
+import com.mojang.brigadier.Command;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.tree.LiteralCommandNode;
 import de.shiewk.smoderation.paper.SModerationPaper;
 import de.shiewk.smoderation.paper.event.VanishToggleEvent;
-import de.shiewk.smoderation.paper.util.PlayerUtil;
+import de.shiewk.smoderation.paper.util.CommandUtil;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
+import io.papermc.paper.command.brigadier.argument.ArgumentTypes;
+import io.papermc.paper.command.brigadier.argument.resolvers.selector.PlayerSelectorArgumentResolver;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 import it.unimi.dsi.fastutil.objects.ObjectListIterator;
 import net.kyori.adventure.text.Component;
-import net.kyori.adventure.text.format.NamedTextColor;
 import org.bukkit.Bukkit;
-import org.bukkit.command.Command;
 import org.bukkit.command.CommandSender;
-import org.bukkit.command.TabExecutor;
 import org.bukkit.entity.Player;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
+import java.util.Collection;
 import java.util.List;
 
 import static de.shiewk.smoderation.paper.SModerationPaper.*;
+import static io.papermc.paper.command.brigadier.Commands.argument;
+import static io.papermc.paper.command.brigadier.Commands.literal;
 import static net.kyori.adventure.text.Component.text;
 
-public class VanishCommand implements TabExecutor {
+public final class VanishCommand implements CommandProvider {
 
     @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length == 0 || args[0].equalsIgnoreCase("toggle")){
-            Player player = null;
-            if (args.length > 1){
-                player = PlayerUtil.findOnlinePlayer(args[1]);
-            } else if (sender instanceof Player){
-                player = (Player) sender;
+    public LiteralCommandNode<CommandSourceStack> getCommandNode() {
+        return literal("vanish")
+                .requires(CommandUtil.requirePermission("smod.vanish"))
+                .executes(this::toggleVanishSelf)
+                .then(literal("toggle")
+                        .executes(this::toggleVanishSelf)
+                        .then(argument("targets", ArgumentTypes.players())
+                                .executes(this::toggleVanishForTargets)
+                        )
+                )
+                .then(literal("list")
+                        .requires(CommandUtil.requirePermission("smod.vanish.see"))
+                        .executes(this::listVanishedPlayers)
+                )
+                .build();
     }
-            if (player != null){
-                toggleVanish(player);
-                return true;
+
+    private int toggleVanishForTargets(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        List<Player> targets = context.getArgument("targets", PlayerSelectorArgumentResolver.class).resolve(context.getSource());
+        if (targets.isEmpty()){
+            CommandUtil.error("No player was found.");
         } else {
-                return false;
+            for (Player target : targets) {
+                toggleVanish(target);
             }
-        } else if (args[0].equalsIgnoreCase("list")) {
-            if (sender.hasPermission("smod.vanish.see")){
-                listVanishedPlayersTo(sender);
-            } else {
-                sender.sendMessage(text().color(NamedTextColor.RED).content("You do not have permission to list all vanished players."));
         }
-            return true;
-        } else {
-            return false;
+        return Command.SINGLE_SUCCESS;
     }
+
+    private int toggleVanishSelf(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
+        toggleVanish(CommandUtil.getExecutingPlayer(context.getSource()));
+        return Command.SINGLE_SUCCESS;
+    }
+
+    private int listVanishedPlayers(CommandContext<CommandSourceStack> context) {
+        listVanishedPlayersTo(context.getSource().getSender());
+        return Command.SINGLE_SUCCESS;
     }
 
     @Override
-    public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if (args.length < 2){
-            return List.of("list", "toggle");
-        }
-        if (args.length < 3 && args[0].equalsIgnoreCase("toggle")){
-            return PlayerUtil.listPlayerNames(args[1]);
-        }
-        return List.of();
+    public String getCommandDescription() {
+        return "Toggles vanish mode which prevents other players from seeing you're online";
     }
 
-    private static final ObjectArrayList<Player> vanishedPlayers = new ObjectArrayList<>();
+    @Override
+    public Collection<String> getAliases() {
+        return List.of("smvanish", "smodvanish", "v", "smv");
+    }
+
+    private static final ObjectArrayList<Player> vanishedPlayers = new ObjectArrayList<>(1);
 
     public static void toggleVanish(Player player){
         final boolean newStatus = !isVanished(player);
@@ -73,10 +90,8 @@ public class VanishCommand implements TabExecutor {
             vanishedPlayers.add(player);
             for (CommandSender sender : SModerationPaper.container.collectBroadcastTargets()) {
                 sender.sendMessage(CHAT_PREFIX.append(
-                        player.displayName()
-                                .colorIfAbsent(SECONDARY_COLOR)
-                ).append(
-                        text()
+                        player.displayName().colorIfAbsent(SECONDARY_COLOR)
+                ).append(text()
                         .content(" vanished.")
                         .color(PRIMARY_COLOR)
                 ));
@@ -92,10 +107,8 @@ public class VanishCommand implements TabExecutor {
             vanishedPlayers.remove(player);
             for (CommandSender sender : container.collectBroadcastTargets()) {
                 sender.sendMessage(CHAT_PREFIX.append(
-                        player.displayName()
-                                .colorIfAbsent(SECONDARY_COLOR)
-                ).append(
-                        text()
+                        player.displayName().colorIfAbsent(SECONDARY_COLOR)
+                ).append(text()
                         .content(" re-appeared.")
                         .color(PRIMARY_COLOR)
                 ));

src/main/java/de/shiewk/smoderation/paper/command/argument/DurationArgument.java

@@ -0,0 +1,74 @@
+package de.shiewk.smoderation.paper.command.argument;
+
+import com.mojang.brigadier.arguments.ArgumentType;
+import com.mojang.brigadier.arguments.StringArgumentType;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.suggestion.Suggestions;
+import com.mojang.brigadier.suggestion.SuggestionsBuilder;
+import de.shiewk.smoderation.paper.util.CommandUtil;
+import io.papermc.paper.command.brigadier.argument.CustomArgumentType;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.regex.MatchResult;
+import java.util.regex.Pattern;
+
+public final class DurationArgument implements CustomArgumentType.Converted<Long, String> {
+
+    public static final Pattern DURATION_PATTERN = Pattern.compile("([0-9]{1,9})(ms|s|min|h|d|w|mo|y)");
+    public static final Pattern VALIDATION_PATTERN = Pattern.compile("(([0-9]{1,9})(ms|s|min|h|d|w|mo|y))+");
+
+    @Override
+    public @NotNull Long convert(@NotNull String nativeType) throws CommandSyntaxException {
+        if (!VALIDATION_PATTERN.matcher(nativeType).matches()){
+            CommandUtil.error("Please provide a valid duration, e.g. '1d6h30min'");
+        }
+        AtomicLong totalDuration = new AtomicLong();
+        for (MatchResult result : DURATION_PATTERN.matcher(nativeType).results().toList()) {
+            long amount = Long.parseLong(result.group(1));
+            long timeSpan = switch (result.group(2)) {
+                case "ms" -> 1;
+                case "s" -> 1000;
+                case "min" -> 60_000;
+                case "h" -> 3600_000;
+                case "d" -> 86400_000;
+                case "w" -> 604800_000;
+                case "mo" -> 2_592_000_000L;
+                case "y" -> 31_536_000_000L;
+                default -> {
+                    CommandUtil.error("Invalid time span '%s'".formatted(result.group(2)));
+                    throw new UnknownError(); // can't happen
+                }
+            };
+            totalDuration.addAndGet(amount*timeSpan);
+        }
+        return totalDuration.get();
+    }
+
+    @Override
+    public @NotNull ArgumentType<String> getNativeType() {
+        return StringArgumentType.word();
+    }
+
+    @Override
+    public @NotNull <S> CompletableFuture<Suggestions> listSuggestions(@NotNull CommandContext<S> context, @NotNull SuggestionsBuilder builder) {
+        if (builder.getRemaining().isBlank()){
+            List.of(
+                    "100ms",
+                    "15s",
+                    "2min",
+                    "3h",
+                    "7d",
+                    "1w",
+                    "3mo",
+                    "1y",
+                    "1mo15d",
+                    "2h30min"
+            ).forEach(builder::suggest);
+        }
+        return builder.buildFuture();
+    }
+}

src/main/java/de/shiewk/smoderation/paper/command/argument/PlayerUUIDArgument.java

@@ -0,0 +1,51 @@
+package de.shiewk.smoderation.paper.command.argument;
+
+import com.mojang.brigadier.arguments.ArgumentType;
+import com.mojang.brigadier.arguments.StringArgumentType;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.suggestion.Suggestions;
+import com.mojang.brigadier.suggestion.SuggestionsBuilder;
+import de.shiewk.smoderation.paper.util.CommandUtil;
+import io.papermc.paper.command.brigadier.argument.CustomArgumentType;
+import org.bukkit.Bukkit;
+import org.bukkit.OfflinePlayer;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
+
+public final class PlayerUUIDArgument implements CustomArgumentType.Converted<UUID, String> {
+
+    @Override
+    public @NotNull UUID convert(@NotNull String nativeType) throws CommandSyntaxException {
+        try {
+            return UUID.fromString(nativeType);
+        } catch (IllegalArgumentException e) {
+            OfflinePlayer player = Bukkit.getOfflinePlayerIfCached(nativeType);
+            if (player != null){
+                return player.getUniqueId();
+            } else {
+                CommandUtil.error("This player is not cached. Try providing an UUID instead.");
+                throw new UnknownError(); // can't happen
+            }
+        }
+    }
+
+    @Override
+    public @NotNull ArgumentType<String> getNativeType() {
+        return StringArgumentType.word();
+    }
+
+    @Override
+    public @NotNull <S> CompletableFuture<Suggestions> listSuggestions(@NotNull CommandContext<S> context, @NotNull SuggestionsBuilder builder) {
+        Bukkit.getOnlinePlayers()
+                .stream()
+                .map(Player::getName)
+                .filter(name -> name.toLowerCase().startsWith(builder.getRemainingLowerCase()))
+                .forEach(builder::suggest);
+        return builder.buildFuture();
+    }
+
+}

src/main/java/de/shiewk/smoderation/paper/util/CommandUtil.java

@@ -0,0 +1,66 @@
+package de.shiewk.smoderation.paper.util;
+
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.exceptions.SimpleCommandExceptionType;
+import io.papermc.paper.command.brigadier.CommandSourceStack;
+import io.papermc.paper.command.brigadier.MessageComponentSerializer;
+import io.papermc.paper.command.brigadier.argument.resolvers.selector.PlayerSelectorArgumentResolver;
+import net.kyori.adventure.text.Component;
+import org.bukkit.command.CommandSender;
+import org.bukkit.command.ConsoleCommandSender;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+import java.util.UUID;
+import java.util.function.Predicate;
+
+import static de.shiewk.smoderation.paper.util.PlayerUtil.UUID_CONSOLE;
+
+public abstract class CommandUtil {
+    private CommandUtil(){}
+
+    public static Predicate<CommandSourceStack> requirePermission(String permission) {
+        return stack -> stack.getSender().hasPermission(permission);
+    }
+
+    public static Player getExecutingPlayer(CommandSourceStack stack) throws CommandSyntaxException {
+        CommandSender sender = stack.getSender();
+        if (sender instanceof Player player) {
+            return player;
+        } else {
+            error("Only players can execute this command.");
+            throw new UnknownError(); // can't happen
+        }
+    }
+
+    public static UUID getSenderUUID(CommandSourceStack stack) throws CommandSyntaxException {
+        CommandSender sender = stack.getSender();
+        if (sender instanceof Player player) {
+            return player.getUniqueId();
+        } else if (sender instanceof ConsoleCommandSender){
+            return UUID_CONSOLE;
+        } else {
+            error("Only players and the console can execute this command.");
+            throw new UnknownError(); // can't happen
+        }
+    }
+
+    public static Player getPlayerSingle(CommandContext<CommandSourceStack> context, String name) throws CommandSyntaxException {
+        @NotNull List<Player> players = context.getArgument(name, PlayerSelectorArgumentResolver.class).resolve(context.getSource());
+        if (players.isEmpty()){
+            CommandUtil.error("Please provide a valid player.");
+        }
+        return players.getFirst();
+    }
+
+    public static void error(String message) throws CommandSyntaxException {
+        throw new CommandSyntaxException(
+                new SimpleCommandExceptionType(null),
+                MessageComponentSerializer.message().serialize(
+                        Component.text(message)
+                )
+        );
+    }
+}

src/main/resources/plugin.yml

@@ -1,94 +1,11 @@
 name: SModeration
 version: '${version}'
 main: de.shiewk.smoderation.paper.SModerationPaper
-api-version: '1.20'
+api-version: '1.21'
 load: STARTUP
 authors:
   - Shiewk
 description: "SModeration is an easy-to-use minecraft plugin for moderating your server."
-commands:
-  modlogs:
-    usage: "§cUsage: /modlogs <player|uuid>"
-    aliases:
-      - logs
-      - seen
-      - smodlogs
-    permission: smod.logs
-  mute:
-    usage: "§cUsage: /mute <player> <duration> <reason>"
-    aliases:
-      - smodmute
-    permission: smod.mute
-    description: Mutes a player, either temporarily or permanently.
-  ban:
-    usage: "§cUsage: /ban <player> <duration> <reason>"
-    aliases:
-      - smodban
-      - tempban
-    permission: smod.ban
-    description: Bans a player, either temporarily or permanently.
-  kick:
-    usage: "§cUsage: /kick <player> <reason>"
-    aliases:
-      - smodkick
-    permission: smod.kick
-    description: Kicks a player
-  smod:
-    usage: "§cUsage: /smod"
-    aliases:
-      - smodmenu
-      - smoderation
-    permission: smod.menu
-    description: Shows the SModeration menu.
-  unmute:
-    usage: "§cUsage: /unmute <player|uuid>"
-    aliases:
-      - sunmute
-    permission: smod.unmute
-    description: Unmutes a muted player.
-  unban:
-    usage: "§cUsage: /unban <player|uuid>"
-    aliases:
-      - sunban
-      - pardon
-      - spardon
-    permission: smod.unban
-    description: Unbans a banned player.
-  invsee:
-    usage: "§cUsage: /invsee <player>"
-    aliases:
-      - sinvsee
-      - smodinvsee
-      - invs
-    permission: smod.invsee
-    description: Views the inventory of another player.
-  enderchestsee:
-    usage: "§cUsage: /enderchestsee <player>"
-    aliases:
-      - secsee
-      - senderchestsee
-      - ecsee
-      - ecs
-    permission: smod.enderchestsee
-    description: Views the ender chest of another player.
-  vanish:
-    usage: "§cUsage: /vanish list or /vanish toggle <player>"
-    aliases:
-      - smvanish
-      - smodvanish
-      - v
-      - smv
-    permission: smod.vanish
-    description: Toggles vanish mode which prevents other players from seeing you're online
-  socialspy:
-    usage: "§cUsage: /socialspy"
-    description: Enables socialspy mode (you can see private messages of other players)
-    permission: smod.socialspy
-    aliases:
-      - smodsocialspy
-      - smsocialspy
-      - smss
-      - ss
 permissions:
   smod.mute:
     default: op
@@ -140,10 +57,10 @@ permissions:
     description: Prevents the player from being muted (if online)
   smod.preventkick:
     default: op
-    description: Prevents the player from being muted (if online)
+    description: Prevents the player from being kicked (if online)
   smod.preventban:
     default: op
-    description: Prevents the player from being muted (if online)
+    description: Prevents the player from being banned (if online)
   smod.vanish:
     default: op
     description: Allows the player to use /vanish