fix: NMS exceptions being thrown when applying modifiers

Spigot's validation for this is like my hoover: it sucks.

README.md

@@ -5,7 +5,7 @@
         <img src="https://img.shields.io/github/actions/workflow/status/WiIIiam278/HuskSync/ci.yml?branch=master&logo=github"/>
     </a>
     <a href="https://repo.william278.net/#/releases/net/william278/husksync/">
-        <img src="https://repo.william278.net/api/badge/latest/releases/net/william278/husksync?color=00fb9a&name=Maven&prefix=v" />
+        <img src="https://repo.william278.net/api/badge/latest/releases/net/william278/husksync/husksync-common?color=00fb9a&name=Maven&prefix=v" />
     </a>
     <a href="https://discord.gg/tVYhJfyDWG">
         <img src="https://img.shields.io/discord/818135932103557162.svg?label=&logo=discord&logoColor=fff&color=7389D8&labelColor=6A7EC2" />
@@ -44,15 +44,15 @@
 **Ready?** [It's syncing time!](https://william278.net/docs/husksync/setup)
 
 ## Setup
-Requires a MySQL/Mongo/PostgreSQL database, a Redis (v5.0+) server and any number of Spigot-based 1.17.1+ Minecraft servers, running Java 17+.
+Requires a MySQL/Mongo/PostgreSQL database, a Redis (v5.0+) server and a network of Spigot (1.17.1+) or Fabric (1.20.1) Minecraft servers, running Java 17+.
 
-1. Place the plugin jar file in the /plugins/ directory of each Spigot server. You do not need to install HuskSync as a proxy plugin.
+1. Place the plugin jar file in the `/plugins` or `/mods` directory of each Spigot/Fabric server. You do not need to install HuskSync as a proxy plugin.
 2. Start, then stop every server to let HuskSync generate the config file.
-3. Navigate to the HuskSync config file on each server (~/plugins/HuskSync/config.yml) and fill in both your database and Redis server credentials.
+3. Navigate to the HuskSync config file on each server and fill in both your database and Redis server credentials.
 4. Start every server again and synchronization will begin.
 
 ## Development
-To build HuskSync, simply run the following in the root of the repository:
+To build HuskSync, simply run the following in the root of the repository (building requires Java 17). Builds will be output in `/target`:
 
 ```bash
 ./gradlew clean build
@@ -66,7 +66,7 @@ HuskSync is licensed under the Apache 2.0 license.
 Contributions to the project are welcome&mdash;feel free to open a pull request with new features, improvements and/or fixes!
 
 ### Support
-Due to its complexity, official binaries and customer support for HuskSync is provided through a paid model. This means that support is only available to users who have purchased a license to the plugin from Spigot, Polymart, Craftaro, or BuiltByBit and have provided proof of purchase. Please join our Discord server if you have done so and need help!
+Due to its complexity, official binaries and customer support for HuskSync is provided through a paid model. This means that support is only available to users who have purchased a license to the plugin from Spigot, Polymart, or BuiltByBit and have provided proof of purchase. Please join our Discord server if you have done so and need help!
 
 ### Translations
 Translations of the plugin locales are welcome to help make the plugin more accessible. Please submit a pull request with your translations as a `.yml` file.

build.gradle

@@ -3,6 +3,7 @@ import org.apache.tools.ant.filters.ReplaceTokens
 plugins {
     id 'com.github.johnrengelman.shadow' version '8.1.1'
     id 'org.cadixdev.licenser' version '0.6.1' apply false
+    id 'fabric-loom' version '1.7-SNAPSHOT' apply false
     id 'org.ajoberstar.grgit' version '5.2.2'
     id 'maven-publish'
     id 'java'
@@ -69,6 +70,8 @@ allprojects {
     repositories {
         mavenLocal()
         mavenCentral()
+        maven { url 'https://repo.william278.net/releases/' }
+        maven { url 'https://oss.sonatype.org/content/repositories/snapshots' }
         maven { url 'https://hub.spigotmc.org/nexus/content/repositories/snapshots/' }
         maven { url "https://repo.dmulloy2.net/repository/public/" }
         maven { url 'https://repo.codemc.io/repository/maven-public/' }
@@ -77,7 +80,6 @@ allprojects {
         maven { url 'https://jitpack.io' }
         maven { url 'https://mvn-repo.arim.space/lesser-gpl3/' }
         maven { url 'https://libraries.minecraft.net/' }
-        maven { url 'https://repo.william278.net/releases/' }
     }
 
     dependencies {
@@ -105,6 +107,10 @@ allprojects {
 }
 
 subprojects {
+    if (['fabric'].contains(project.name)) {
+        apply plugin: 'fabric-loom'
+    }
+
     version rootProject.version
     archivesBaseName = "${rootProject.name}-${project.name.capitalize()}"
 
@@ -117,8 +123,13 @@ subprojects {
         archiveClassifier.set('')
     }
 
+    // Append the Minecraft to the version for Fabric projects
+    if (project.name == 'fabric') {
+        version += "+mc.${fabric_minecraft_version}"
+    }
+
     // API publishing
-    if (['common', 'bukkit'].contains(project.name)) {
+    if (['common', 'bukkit', 'fabric'].contains(project.name)) {
         java {
             withSourcesJar()
             withJavadocJar()
@@ -157,6 +168,19 @@ subprojects {
                     }
                 }
             }
+
+            if (['fabric'].contains(project.name)) {
+                publications {
+                    mavenJavaFabric(MavenPublication) {
+                        groupId = 'net.william278.husksync'
+                        artifactId = 'husksync-fabric'
+                        version = "$rootProject.version+${fabric_minecraft_version}"
+                        artifact remapJar
+                        artifact sourcesJar
+                        artifact javadocJar
+                    }
+                }
+            }
         }
     }
 

bukkit/build.gradle

@@ -1,18 +1,19 @@
 dependencies {
     implementation project(path: ':common')
 
-    implementation 'org.bstats:bstats-bukkit:3.0.2'
+    implementation 'net.william278.uniform:uniform-bukkit:1.1.8'
     implementation 'net.william278:mpdbdataconverter:1.0.1'
     implementation 'net.william278:hsldataconverter:1.0'
     implementation 'net.william278:mapdataapi:1.0.3'
     implementation 'net.william278:andjam:1.0.2'
-    implementation 'me.lucko:commodore:2.2'
-    implementation 'net.kyori:adventure-platform-bukkit:4.3.2'
-    implementation 'dev.triumphteam:triumph-gui:3.1.7'
+    implementation 'org.bstats:bstats-bukkit:3.0.2'
+    implementation 'net.kyori:adventure-platform-bukkit:4.3.3'
+    implementation 'dev.triumphteam:triumph-gui:3.1.10'
     implementation 'space.arim.morepaperlib:morepaperlib:0.4.4'
-    implementation 'de.tr7zw:item-nbt-api:2.12.4'
+    implementation 'de.tr7zw:item-nbt-api:2.13.1'
 
     compileOnly 'org.spigotmc:spigot-api:1.17.1-R0.1-SNAPSHOT'
+    compileOnly 'com.github.retrooper.packetevents:spigot:2.3.0'
     compileOnly 'com.comphenix.protocol:ProtocolLib:5.1.0'
     compileOnly 'org.projectlombok:lombok:1.18.32'
     compileOnly 'commons-io:commons-io:2.16.1'
@@ -41,6 +42,7 @@ shadowJar {
     relocate 'org.intellij', 'net.william278.husksync.libraries'
     relocate 'com.zaxxer', 'net.william278.husksync.libraries'
     relocate 'de.exlll', 'net.william278.husksync.libraries'
+    relocate 'net.william278.uniform', 'net.william278.husksync.libraries.uniform'
     relocate 'net.william278.desertwell', 'net.william278.husksync.libraries.desertwell'
     relocate 'net.william278.paginedown', 'net.william278.husksync.libraries.paginedown'
     relocate 'net.william278.mapdataapi', 'net.william278.husksync.libraries.mapdataapi'
@@ -50,7 +52,6 @@ shadowJar {
     relocate 'org.json', 'net.william278.husksync.libraries.json'
     relocate 'net.querz', 'net.william278.husksync.libraries.nbtparser'
     relocate 'net.roxeez', 'net.william278.husksync.libraries'
-    relocate 'me.lucko.commodore', 'net.william278.husksync.libraries.commodore'
     relocate 'org.bstats', 'net.william278.husksync.libraries.bstats'
     relocate 'dev.triumphteam.gui', 'net.william278.husksync.libraries.triumphgui'
     relocate 'space.arim.morepaperlib', 'net.william278.husksync.libraries.paperlib'

bukkit/src/main/java/net/william278/husksync/BukkitHuskSync.java

@@ -34,7 +34,7 @@ import net.william278.husksync.adapter.DataAdapter;
 import net.william278.husksync.adapter.GsonAdapter;
 import net.william278.husksync.adapter.SnappyGsonAdapter;
 import net.william278.husksync.api.BukkitHuskSyncAPI;
-import net.william278.husksync.command.BukkitCommand;
+import net.william278.husksync.command.PluginCommand;
 import net.william278.husksync.config.Locales;
 import net.william278.husksync.config.Server;
 import net.william278.husksync.config.Settings;
@@ -46,7 +46,6 @@ import net.william278.husksync.database.PostgresDatabase;
 import net.william278.husksync.event.BukkitEventDispatcher;
 import net.william278.husksync.hook.PlanHook;
 import net.william278.husksync.listener.BukkitEventListener;
-import net.william278.husksync.listener.EventListener;
 import net.william278.husksync.migrator.LegacyMigrator;
 import net.william278.husksync.migrator.Migrator;
 import net.william278.husksync.migrator.MpdbMigrator;
@@ -58,13 +57,15 @@ import net.william278.husksync.util.BukkitLegacyConverter;
 import net.william278.husksync.util.BukkitMapPersister;
 import net.william278.husksync.util.BukkitTask;
 import net.william278.husksync.util.LegacyConverter;
+import net.william278.uniform.Uniform;
+import net.william278.uniform.bukkit.BukkitUniform;
 import org.bstats.bukkit.Metrics;
 import org.bukkit.entity.Player;
 import org.bukkit.map.MapView;
+import org.bukkit.plugin.Plugin;
 import org.bukkit.plugin.java.JavaPlugin;
 import org.jetbrains.annotations.NotNull;
 import space.arim.morepaperlib.MorePaperLib;
-import space.arim.morepaperlib.commands.CommandRegistration;
 import space.arim.morepaperlib.scheduling.AsynchronousScheduler;
 import space.arim.morepaperlib.scheduling.AttachedScheduler;
 import space.arim.morepaperlib.scheduling.GracefulScheduling;
@@ -86,7 +87,9 @@ public class BukkitHuskSync extends JavaPlugin implements HuskSync, BukkitTask.S
     private static final int METRICS_ID = 13140;
     private static final String PLATFORM_TYPE_ID = "bukkit";
 
-    private final Map<Identifier, Serializer<? extends Data>> serializers = Maps.newLinkedHashMap();
+    private final TreeMap<Identifier, Serializer<? extends Data>> serializers = Maps.newTreeMap(
+            SerializerRegistry.DEPENDENCY_ORDER_COMPARATOR
+    );
     private final Map<UUID, Map<Identifier, Data>> playerCustomDataStore = Maps.newConcurrentMap();
     private final Map<Integer, MapView> mapViews = Maps.newConcurrentMap();
     private final List<Migrator> availableMigrators = Lists.newArrayList();
@@ -98,7 +101,7 @@ public class BukkitHuskSync extends JavaPlugin implements HuskSync, BukkitTask.S
     private MorePaperLib paperLib;
     private Database database;
     private RedisManager redisManager;
-    private EventListener eventListener;
+    private BukkitEventListener eventListener;
     private DataAdapter dataAdapter;
     private DataSyncer dataSyncer;
     private LegacyConverter legacyConverter;
@@ -113,11 +116,10 @@ public class BukkitHuskSync extends JavaPlugin implements HuskSync, BukkitTask.S
     private Server serverName;
 
     @Override
-    public void onEnable() {
+    public void onLoad() {
         // Initial plugin setup
         this.disabling = false;
         this.gson = createGson();
-        this.audiences = BukkitAudiences.create(this);
         this.paperLib = new MorePaperLib(this);
 
         // Load settings and locales
@@ -127,6 +129,17 @@ public class BukkitHuskSync extends JavaPlugin implements HuskSync, BukkitTask.S
             loadServer();
         });
 
+        this.eventListener = createEventListener();
+        eventListener.onLoad();
+    }
+
+    @Override
+    public void onEnable() {
+        this.audiences = BukkitAudiences.create(this);
+
+        // Register commands
+        initialize("commands", (plugin) -> getUniform().register(PluginCommand.Type.create(this)));
+
         // Prepare data adapter
         initialize("data adapter", (plugin) -> {
             if (settings.getSynchronization().isCompressData()) {
@@ -138,19 +151,20 @@ public class BukkitHuskSync extends JavaPlugin implements HuskSync, BukkitTask.S
 
         // Prepare serializers
         initialize("data serializers", (plugin) -> {
+            registerSerializer(Identifier.PERSISTENT_DATA, new BukkitSerializer.PersistentData(this));
             registerSerializer(Identifier.INVENTORY, new BukkitSerializer.Inventory(this));
             registerSerializer(Identifier.ENDER_CHEST, new BukkitSerializer.EnderChest(this));
             registerSerializer(Identifier.ADVANCEMENTS, new BukkitSerializer.Advancements(this));
-            registerSerializer(Identifier.LOCATION, new BukkitSerializer.Json<>(this, BukkitData.Location.class));
-            registerSerializer(Identifier.HEALTH, new BukkitSerializer.Json<>(this, BukkitData.Health.class));
-            registerSerializer(Identifier.HUNGER, new BukkitSerializer.Json<>(this, BukkitData.Hunger.class));
-            registerSerializer(Identifier.ATTRIBUTES, new BukkitSerializer.Json<>(this, BukkitData.Attributes.class));
-            registerSerializer(Identifier.GAME_MODE, new BukkitSerializer.Json<>(this, BukkitData.GameMode.class));
-            registerSerializer(Identifier.FLIGHT_STATUS, new BukkitSerializer.Json<>(this, BukkitData.FlightStatus.class));
+            registerSerializer(Identifier.STATISTICS, new Serializer.Json<>(this, BukkitData.Statistics.class));
             registerSerializer(Identifier.POTION_EFFECTS, new BukkitSerializer.PotionEffects(this));
-            registerSerializer(Identifier.STATISTICS, new BukkitSerializer.Json<>(this, BukkitData.Statistics.class));
-            registerSerializer(Identifier.EXPERIENCE, new BukkitSerializer.Json<>(this, BukkitData.Experience.class));
-            registerSerializer(Identifier.PERSISTENT_DATA, new BukkitSerializer.PersistentData(this));
+            registerSerializer(Identifier.GAME_MODE, new Serializer.Json<>(this, BukkitData.GameMode.class));
+            registerSerializer(Identifier.FLIGHT_STATUS, new Serializer.Json<>(this, BukkitData.FlightStatus.class));
+            registerSerializer(Identifier.ATTRIBUTES, new Serializer.Json<>(this, BukkitData.Attributes.class));
+            registerSerializer(Identifier.HEALTH, new Serializer.Json<>(this, BukkitData.Health.class));
+            registerSerializer(Identifier.HUNGER, new Serializer.Json<>(this, BukkitData.Hunger.class));
+            registerSerializer(Identifier.EXPERIENCE, new Serializer.Json<>(this, BukkitData.Experience.class));
+            registerSerializer(Identifier.LOCATION, new Serializer.Json<>(this, BukkitData.Location.class));
+            validateDependencies();
         });
 
         // Setup available migrators
@@ -185,10 +199,7 @@ public class BukkitHuskSync extends JavaPlugin implements HuskSync, BukkitTask.S
         });
 
         // Register events
-        initialize("events", (plugin) -> this.eventListener = createEventListener());
-
-        // Register commands
-        initialize("commands", (plugin) -> BukkitCommand.Type.registerCommands(this));
+        initialize("events", (plugin) -> eventListener.onEnable());
 
         // Register plugin hooks
         initialize("hooks", (plugin) -> {
@@ -255,6 +266,12 @@ public class BukkitHuskSync extends JavaPlugin implements HuskSync, BukkitTask.S
         this.dataSyncer = dataSyncer;
     }
 
+    @Override
+    @NotNull
+    public Uniform getUniform() {
+        return BukkitUniform.getInstance(this);
+    }
+
     @NotNull
     @Override
     public Map<Identifier, Data> getPlayerCustomDataStore(@NotNull OnlineUser user) {
@@ -272,7 +289,8 @@ public class BukkitHuskSync extends JavaPlugin implements HuskSync, BukkitTask.S
 
     @Override
     public boolean isDependencyLoaded(@NotNull String name) {
-        return getServer().getPluginManager().getPlugin(name) != null;
+        final Plugin plugin = getServer().getPluginManager().getPlugin(name);
+        return plugin != null && plugin.isEnabled();
     }
 
     // Register bStats metrics
@@ -284,7 +302,7 @@ public class BukkitHuskSync extends JavaPlugin implements HuskSync, BukkitTask.S
         try {
             new Metrics(this, metricsId);
         } catch (Throwable e) {
-            log(Level.WARNING, "Failed to register bStats metrics (" + e.getMessage() + ")");
+            log(Level.WARNING, "Failed to register bStats metrics (%s)".formatted(e.getMessage()));
         }
     }
 
@@ -342,11 +360,6 @@ public class BukkitHuskSync extends JavaPlugin implements HuskSync, BukkitTask.S
         return getScheduler().entitySpecificScheduler(((BukkitUser) user).getPlayer());
     }
 
-    @NotNull
-    public CommandRegistration getCommandRegistrar() {
-        return paperLib.commandRegistration();
-    }
-
     @Override
     @NotNull
     public Path getConfigDirectory() {

bukkit/src/main/java/net/william278/husksync/api/BukkitHuskSyncAPI.java

@@ -28,6 +28,7 @@ import net.william278.husksync.user.OnlineUser;
 import net.william278.husksync.user.User;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
+import org.bukkit.plugin.java.JavaPlugin;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
@@ -59,6 +60,10 @@ public class BukkitHuskSyncAPI extends HuskSyncAPI {
      */
     @NotNull
     public static BukkitHuskSyncAPI getInstance() {
+        if (!JavaPlugin.getProvidingPlugin(BukkitHuskSyncAPI.class).getName().equals("HuskSync")) {
+            throw new NotRegisteredException("This is likely because you have shaded HuskSync into your plugin JAR " +
+                    "and need to fix your maven/gradle/build script so that it *compiles against* HuskSync instead.");
+        }
         if (instance == null) {
             throw new NotRegisteredException();
         }

bukkit/src/main/java/net/william278/husksync/command/BrigadierUtil.java

@@ -1,60 +0,0 @@
-/*
- * This file is part of HuskSync, licensed under the Apache License 2.0.
- *
- *  Copyright (c) William278 <will27528@gmail.com>
- *  Copyright (c) contributors
- *
- *  Licensed under the Apache License, Version 2.0 (the "License");
- *  you may not use this file except in compliance with the License.
- *  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- *  Unless required by applicable law or agreed to in writing, software
- *  distributed under the License is distributed on an "AS IS" BASIS,
- *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- *  See the License for the specific language governing permissions and
- *  limitations under the License.
- */
-
-package net.william278.husksync.command;
-
-import me.lucko.commodore.CommodoreProvider;
-import me.lucko.commodore.file.CommodoreFileReader;
-import net.william278.husksync.BukkitHuskSync;
-import org.jetbrains.annotations.NotNull;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.util.logging.Level;
-
-public class BrigadierUtil {
-
-    /**
-     * Uses commodore to register command completions.
-     *
-     * @param plugin        instance of the registering Bukkit plugin
-     * @param bukkitCommand the Bukkit PluginCommand to register completions for
-     * @param command       the {@link Command} to register completions for
-     */
-    protected static void registerCommodore(@NotNull BukkitHuskSync plugin,
-                                            @NotNull org.bukkit.command.Command bukkitCommand,
-                                            @NotNull Command command) {
-        final InputStream commodoreFile = plugin.getResource(
-                "commodore/" + bukkitCommand.getName() + ".commodore"
-        );
-        if (commodoreFile == null) {
-            return;
-        }
-        try {
-            CommodoreProvider.getCommodore(plugin).register(bukkitCommand,
-                    CommodoreFileReader.INSTANCE.parse(commodoreFile),
-                    player -> player.hasPermission(command.getPermission()));
-        } catch (IOException e) {
-            plugin.log(Level.SEVERE, String.format(
-                    "Failed to read command commodore completions for %s", bukkitCommand.getName()), e
-            );
-        }
-    }
-
-}

bukkit/src/main/java/net/william278/husksync/command/BukkitCommand.java

@@ -1,164 +0,0 @@
-/*
- * This file is part of HuskSync, licensed under the Apache License 2.0.
- *
- *  Copyright (c) William278 <will27528@gmail.com>
- *  Copyright (c) contributors
- *
- *  Licensed under the Apache License, Version 2.0 (the "License");
- *  you may not use this file except in compliance with the License.
- *  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- *  Unless required by applicable law or agreed to in writing, software
- *  distributed under the License is distributed on an "AS IS" BASIS,
- *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- *  See the License for the specific language governing permissions and
- *  limitations under the License.
- */
-
-package net.william278.husksync.command;
-
-
-import me.lucko.commodore.CommodoreProvider;
-import net.william278.husksync.BukkitHuskSync;
-import net.william278.husksync.user.BukkitUser;
-import net.william278.husksync.user.CommandUser;
-import org.bukkit.command.CommandSender;
-import org.bukkit.entity.Player;
-import org.bukkit.permissions.Permission;
-import org.bukkit.permissions.PermissionDefault;
-import org.bukkit.plugin.PluginManager;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-
-import java.util.*;
-import java.util.function.Function;
-
-public class BukkitCommand extends org.bukkit.command.Command {
-
-    private final BukkitHuskSync plugin;
-    private final Command command;
-
-    public BukkitCommand(@NotNull Command command, @NotNull BukkitHuskSync plugin) {
-        super(command.getName(), command.getDescription(), command.getUsage(), command.getAliases());
-        this.command = command;
-        this.plugin = plugin;
-    }
-
-    @Override
-    public boolean execute(@NotNull CommandSender sender, @NotNull String commandLabel, @NotNull String[] args) {
-        this.command.onExecuted(sender instanceof Player p ? BukkitUser.adapt(p, plugin) : plugin.getConsole(), args);
-        return true;
-    }
-
-    @NotNull
-    @Override
-    public List<String> tabComplete(@NotNull CommandSender sender, @NotNull String alias,
-                                    @NotNull String[] args) throws IllegalArgumentException {
-        if (!(this.command instanceof TabProvider provider)) {
-            return List.of();
-        }
-        final CommandUser user = sender instanceof Player p ? BukkitUser.adapt(p, plugin) : plugin.getConsole();
-        if (getPermission() == null || user.hasPermission(getPermission())) {
-            return provider.getSuggestions(user, args);
-        }
-        return List.of();
-    }
-
-    public void register() {
-        // Register with bukkit
-        plugin.getCommandRegistrar().getServerCommandMap().register("husksync", this);
-
-        // Register permissions
-        BukkitCommand.addPermission(
-                plugin,
-                command.getPermission(),
-                command.getUsage(),
-                BukkitCommand.getPermissionDefault(command.isOperatorCommand())
-        );
-        final List<Permission> childNodes = command.getAdditionalPermissions()
-                .entrySet().stream()
-                .map((entry) -> BukkitCommand.addPermission(
-                        plugin,
-                        entry.getKey(),
-                        "",
-                        BukkitCommand.getPermissionDefault(entry.getValue()))
-                )
-                .filter(Objects::nonNull)
-                .toList();
-        if (!childNodes.isEmpty()) {
-            BukkitCommand.addPermission(
-                    plugin,
-                    command.getPermission("*"),
-                    command.getUsage(),
-                    PermissionDefault.FALSE,
-                    childNodes.toArray(new Permission[0])
-            );
-        }
-
-        // Register commodore TAB completion
-        if (CommodoreProvider.isSupported() && plugin.getSettings().isBrigadierTabCompletion()) {
-            BrigadierUtil.registerCommodore(plugin, this, command);
-        }
-    }
-
-    @Nullable
-    protected static Permission addPermission(@NotNull BukkitHuskSync plugin, @NotNull String node,
-                                              @NotNull String description, @NotNull PermissionDefault permissionDefault,
-                                              @NotNull Permission... children) {
-        final Map<String, Boolean> childNodes = Arrays.stream(children)
-                .map(Permission::getName)
-                .collect(HashMap::new, (map, child) -> map.put(child, true), HashMap::putAll);
-
-        final PluginManager manager = plugin.getServer().getPluginManager();
-        if (manager.getPermission(node) != null) {
-            return null;
-        }
-
-        Permission permission;
-        if (description.isEmpty()) {
-            permission = new Permission(node, permissionDefault, childNodes);
-        } else {
-            permission = new Permission(node, description, permissionDefault, childNodes);
-        }
-        manager.addPermission(permission);
-
-        return permission;
-    }
-
-    @NotNull
-    protected static PermissionDefault getPermissionDefault(boolean isOperatorCommand) {
-        return isOperatorCommand ? PermissionDefault.OP : PermissionDefault.TRUE;
-    }
-
-    /**
-     * Commands available on the Bukkit HuskSync implementation
-     */
-    public enum Type {
-
-        HUSKSYNC_COMMAND(HuskSyncCommand::new),
-        USERDATA_COMMAND(UserDataCommand::new),
-        INVENTORY_COMMAND(InventoryCommand::new),
-        ENDER_CHEST_COMMAND(EnderChestCommand::new);
-
-        public final Function<BukkitHuskSync, Command> commandSupplier;
-
-        Type(@NotNull Function<BukkitHuskSync, Command> supplier) {
-            this.commandSupplier = supplier;
-        }
-
-        @NotNull
-        public Command createCommand(@NotNull BukkitHuskSync plugin) {
-            return commandSupplier.apply(plugin);
-        }
-
-        public static void registerCommands(@NotNull BukkitHuskSync plugin) {
-            Arrays.stream(values())
-                    .map((type) -> type.createCommand(plugin))
-                    .forEach((command) -> new BukkitCommand(command, plugin).register());
-        }
-
-
-    }
-}

bukkit/src/main/java/net/william278/husksync/data/BukkitData.java

@@ -25,7 +25,9 @@ import com.google.gson.annotations.SerializedName;
 import de.tr7zw.changeme.nbtapi.NBTCompound;
 import de.tr7zw.changeme.nbtapi.NBTPersistentDataContainer;
 import lombok.*;
+import net.kyori.adventure.util.TriState;
 import net.william278.desertwell.util.ThrowingConsumer;
+import net.william278.desertwell.util.Version;
 import net.william278.husksync.BukkitHuskSync;
 import net.william278.husksync.HuskSync;
 import net.william278.husksync.adapter.Adaptable;
@@ -34,6 +36,7 @@ import org.bukkit.Bukkit;
 import org.bukkit.Material;
 import org.bukkit.Registry;
 import org.bukkit.Statistic;
+import org.bukkit.NamespacedKey;
 import org.bukkit.advancement.AdvancementProgress;
 import org.bukkit.attribute.AttributeInstance;
 import org.bukkit.attribute.AttributeModifier;
@@ -69,7 +72,6 @@ public abstract class BukkitData implements Data {
         private final @Nullable ItemStack @NotNull [] contents;
 
         private Items(@Nullable ItemStack @NotNull [] contents) {
-
             this.contents = Arrays.stream(contents.clone())
                     .map(i -> i == null || i.getType() == Material.AIR ? null : i)
                     .toArray(ItemStack[]::new);
@@ -127,8 +129,6 @@ public abstract class BukkitData implements Data {
         @Getter
         public static class Inventory extends BukkitData.Items implements Data.Items.Inventory {
 
-            public static final int INVENTORY_SLOT_COUNT = 41;
-
             @Range(from = 0, to = 8)
             private int heldItemSlot;
 
@@ -163,11 +163,15 @@ public abstract class BukkitData implements Data {
             }
 
             private void clearInventoryCraftingSlots(@NotNull Player player) {
-                final org.bukkit.inventory.Inventory inventory = player.getOpenInventory().getTopInventory();
-                if (inventory.getType() == InventoryType.CRAFTING) {
-                    for (int slot = 0; slot < 5; slot++) {
-                        inventory.setItem(slot, null);
+                try {
+                    final org.bukkit.inventory.Inventory inventory = player.getOpenInventory().getTopInventory();
+                    if (inventory.getType() == InventoryType.CRAFTING) {
+                        for (int slot = 0; slot < 5; slot++) {
+                            inventory.setItem(slot, null);
+                        }
                     }
+                } catch (Throwable e) {
+                    // Ignore any exceptions
                 }
             }
 
@@ -175,15 +179,18 @@ public abstract class BukkitData implements Data {
 
         public static class EnderChest extends BukkitData.Items implements Data.Items.EnderChest {
 
-            public static final int ENDER_CHEST_SLOT_COUNT = 27;
-
-            private EnderChest(@NotNull ItemStack[] contents) {
+            private EnderChest(@Nullable ItemStack @NotNull [] contents) {
                 super(contents);
             }
 
             @NotNull
-            public static BukkitData.Items.EnderChest adapt(@NotNull ItemStack[] items) {
-                return new BukkitData.Items.EnderChest(items);
+            public static BukkitData.Items.EnderChest adapt(@Nullable ItemStack @NotNull [] contents) {
+                return new BukkitData.Items.EnderChest(contents);
+            }
+
+            @NotNull
+            public static BukkitData.Items.EnderChest adapt(@NotNull Collection<ItemStack> items) {
+                return adapt(items.toArray(ItemStack[]::new));
             }
 
             @NotNull
@@ -200,7 +207,7 @@ public abstract class BukkitData implements Data {
 
         public static class ItemArray extends BukkitData.Items implements Data.Items {
 
-            private ItemArray(@NotNull ItemStack[] contents) {
+            private ItemArray(@Nullable ItemStack @NotNull [] contents) {
                 super(contents);
             }
 
@@ -210,7 +217,7 @@ public abstract class BukkitData implements Data {
             }
 
             @NotNull
-            public static ItemArray adapt(@NotNull ItemStack[] drops) {
+            public static ItemArray adapt(@Nullable ItemStack @NotNull [] drops) {
                 return new ItemArray(drops);
             }
 
@@ -237,21 +244,20 @@ public abstract class BukkitData implements Data {
 
         @NotNull
         public static BukkitData.PotionEffects adapt(@NotNull Collection<Effect> effects) {
-            return from(
-                    effects.stream()
-                            .map(effect -> new PotionEffect(
-                                    Objects.requireNonNull(
-                                            PotionEffectType.getByName(effect.type()),
-                                            "Invalid potion effect type"
-                                    ),
-                                    effect.duration(),
-                                    effect.amplifier(),
-                                    effect.isAmbient(),
-                                    effect.showParticles(),
-                                    effect.hasIcon()
-                            ))
-                            .toList()
-            );
+            return from(effects.stream()
+                    .map(effect -> {
+                        final PotionEffectType type = matchEffectType(effect.type());
+                        return type != null ? new PotionEffect(
+                                type,
+                                effect.duration(),
+                                effect.amplifier(),
+                                effect.isAmbient(),
+                                effect.showParticles(),
+                                effect.hasIcon()
+                        ) : null;
+                    })
+                    .filter(Objects::nonNull)
+                    .toList());
         }
 
         @NotNull
@@ -342,9 +348,12 @@ public abstract class BukkitData implements Data {
             }));
         }
 
-        private void setAdvancement(@NotNull HuskSync plugin, @NotNull org.bukkit.advancement.Advancement advancement,
-                                    @NotNull Player player, @NotNull BukkitUser user,
-                                    @NotNull Collection<String> toAward, @NotNull Collection<String> toRevoke) {
+        private void setAdvancement(@NotNull HuskSync plugin,
+                                    @NotNull org.bukkit.advancement.Advancement advancement,
+                                    @NotNull Player player,
+                                    @NotNull BukkitUser user,
+                                    @NotNull Collection<String> toAward,
+                                    @NotNull Collection<String> toRevoke) {
             plugin.runSync(() -> {
                 // Track player exp level & progress
                 final int expLevel = player.getLevel();
@@ -356,7 +365,8 @@ public abstract class BukkitData implements Data {
                 toRevoke.forEach(progress::revokeCriteria);
 
                 // Set player experience and level (prevent advancement awards applying twice), reset game rule
-                if (!toAward.isEmpty() && player.getLevel() != expLevel || player.getExp() != expProgress) {
+                if (!toAward.isEmpty()
+                        && (player.getLevel() != expLevel || player.getExp() != expProgress)) {
                     player.setLevel(expLevel);
                     player.setExp(expProgress);
                 }
@@ -557,6 +567,11 @@ public abstract class BukkitData implements Data {
     @NoArgsConstructor(access = AccessLevel.PRIVATE)
     public static class Attributes extends BukkitData implements Data.Attributes, Adaptable {
 
+        private static final String EQUIPMENT_SLOT_GROUP = "org.bukkit.inventory.EquipmentSlotGroup";
+        private static final String EQUIPMENT_SLOT_GROUP$ANY = "ANY";
+        private static final String EQUIPMENT_SLOT$getGroup = "getGroup";
+        private static TriState USE_KEYED_MODIFIERS = TriState.NOT_SET;
+
         private List<Attribute> attributes;
 
         @NotNull
@@ -564,8 +579,8 @@ public abstract class BukkitData implements Data {
             final List<Attribute> attributes = Lists.newArrayList();
             Registry.ATTRIBUTE.forEach(id -> {
                 final AttributeInstance instance = player.getAttribute(id);
-                if (instance == null || instance.getValue() == instance.getDefaultValue() || plugin
-                        .getSettings().getSynchronization().isIgnoredAttribute(id.getKey().toString())) {
+                if (instance == null || Double.compare(instance.getValue(), instance.getDefaultValue()) == 0
+                        || plugin.getSettings().getSynchronization().isIgnoredAttribute(id.getKey().toString())) {
                     // We don't sync unmodified or disabled attributes
                     return;
                 }
@@ -599,7 +614,7 @@ public abstract class BukkitData implements Data {
         @NotNull
         private static Modifier adapt(@NotNull AttributeModifier modifier) {
             return new Modifier(
-                    modifier.getUniqueId(),
+                    getModifierId(modifier),
                     modifier.getName(),
                     modifier.getAmount(),
                     modifier.getOperation().ordinal(),
@@ -607,28 +622,71 @@ public abstract class BukkitData implements Data {
             );
         }
 
-        @Override
-        public void apply(@NotNull BukkitUser user, @NotNull BukkitHuskSync plugin) throws IllegalStateException {
-            Registry.ATTRIBUTE.forEach(id -> applyAttribute(user.getPlayer().getAttribute(id), getAttribute(id).orElse(null)));
+        @Nullable
+        private static UUID getModifierId(@NotNull AttributeModifier modifier) {
+            try {
+                return modifier.getUniqueId();
+            } catch (Throwable e) {
+                return null;
+            }
         }
 
-        private static void applyAttribute(@Nullable AttributeInstance instance, @Nullable Attribute attribute) {
+        private static void applyAttribute(@Nullable AttributeInstance instance, @Nullable Attribute attribute,
+                                           @NotNull HuskSync plugin) {
             if (instance == null) {
                 return;
             }
-            instance.setBaseValue(attribute == null ? instance.getDefaultValue() : instance.getBaseValue());
+            instance.setBaseValue(attribute == null ? instance.getDefaultValue() : attribute.baseValue());
             instance.getModifiers().forEach(instance::removeModifier);
             if (attribute != null) {
-                attribute.modifiers().forEach(modifier -> instance.addModifier(new AttributeModifier(
-                        modifier.uuid(),
-                        modifier.name(),
-                        modifier.amount(),
-                        AttributeModifier.Operation.values()[modifier.operationType()],
-                        modifier.equipmentSlot() != -1 ? EquipmentSlot.values()[modifier.equipmentSlot()] : null
-                )));
+                attribute.modifiers().forEach(modifier -> instance.addModifier(adapt(modifier, plugin)));
             }
         }
 
+        @SuppressWarnings("JavaReflectionMemberAccess")
+        @NotNull
+        private static AttributeModifier adapt(@NotNull Modifier modifier, @NotNull HuskSync plugin) {
+            final int slotId = modifier.equipmentSlot();
+            if (USE_KEYED_MODIFIERS == TriState.NOT_SET) {
+                USE_KEYED_MODIFIERS = TriState.byBoolean(plugin.getMinecraftVersion()
+                        .compareTo(Version.fromString("1.21")) >= 0);
+            }
+            if (USE_KEYED_MODIFIERS == TriState.TRUE) {
+                try {
+                    // Reflexively create a modern keyed attribute modifier instance. Remove in favor of API long-term.
+                    final EquipmentSlot slot = slotId != -1 ? EquipmentSlot.values()[slotId] : null;
+                    final Class<?> slotGroup = Class.forName(EQUIPMENT_SLOT_GROUP);
+                    final String modifierName = modifier.name() == null ? modifier.uuid().toString() : modifier.name();
+                    return AttributeModifier.class.getDeclaredConstructor(
+                            NamespacedKey.class, double.class, AttributeModifier.Operation.class, slotGroup
+                    ).newInstance(
+                            NamespacedKey.fromString(modifierName),
+                            modifier.amount(),
+                            AttributeModifier.Operation.values()[modifier.operationType()],
+                            slot == null ? slotGroup.getField(EQUIPMENT_SLOT_GROUP$ANY).get(null)
+                                    : EquipmentSlot.class.getDeclaredMethod(EQUIPMENT_SLOT$getGroup).invoke(slot)
+                    );
+                } catch (Throwable e) {
+                    plugin.log(Level.WARNING, "Error reflectively creating keyed attribute modifier", e);
+                    USE_KEYED_MODIFIERS = TriState.FALSE;
+                }
+            }
+            return new AttributeModifier(
+                    modifier.uuid(),
+                    modifier.name(),
+                    modifier.amount(),
+                    AttributeModifier.Operation.values()[modifier.operationType()],
+                    slotId != -1 ? EquipmentSlot.values()[slotId] : null
+            );
+        }
+
+        @Override
+        public void apply(@NotNull BukkitUser user, @NotNull BukkitHuskSync plugin) throws IllegalStateException {
+            Registry.ATTRIBUTE.forEach(id -> applyAttribute(
+                    user.getPlayer().getAttribute(id), getAttribute(id).orElse(null), plugin
+            ));
+        }
+
     }
 
     @Getter
@@ -640,24 +698,38 @@ public abstract class BukkitData implements Data {
         private double health;
         @SerializedName("health_scale")
         private double healthScale;
+        @SerializedName("is_health_scaled")
+        private boolean isHealthScaled;
 
         @NotNull
-        public static BukkitData.Health from(double health, double healthScale) {
-            return new BukkitData.Health(health, healthScale);
+        public static BukkitData.Health from(double health, double scale, boolean isScaled) {
+            return new BukkitData.Health(health, scale, isScaled);
         }
 
+        /**
+         * @deprecated Use {@link #from(double, double, boolean)} instead
+         */
+        @NotNull
+        @Deprecated(since = "3.5.4")
+        public static BukkitData.Health from(double health, double scale) {
+            return from(health, scale, false);
+        }
+
+        /**
+         * @deprecated Use {@link #from(double, double, boolean)} instead
+         */
         @NotNull
         @Deprecated(forRemoval = true, since = "3.5")
-        @SuppressWarnings("unused")
-        public static BukkitData.Health from(double health, double maxHealth, double healthScale) {
-            return from(health, healthScale);
+        public static BukkitData.Health from(double health, @SuppressWarnings("unused") double max, double scale) {
+            return from(health, scale, false);
         }
 
         @NotNull
         public static BukkitData.Health adapt(@NotNull Player player) {
             return from(
                     player.getHealth(),
-                    player.isHealthScaled() ? player.getHealthScale() : 0d
+                    player.getHealthScale(),
+                    player.isHealthScaled()
             );
         }
 
@@ -674,16 +746,12 @@ public abstract class BukkitData implements Data {
             }
 
             // Set health scale
+            double scale = healthScale <= 0 ? player.getMaxHealth() : healthScale;
             try {
-                if (healthScale != 0d) {
-                    player.setHealthScaled(true);
-                    player.setHealthScale(healthScale);
-                } else {
-                    player.setHealthScaled(false);
-                    player.setHealthScale(player.getMaxHealth());
-                }
+                player.setHealthScale(scale);
+                player.setHealthScaled(isHealthScaled);
             } catch (Throwable e) {
-                plugin.log(Level.WARNING, "Error setting %s's health scale to %s".formatted(player.getName(), healthScale), e);
+                plugin.log(Level.WARNING, "Error setting %s's health scale to %s".formatted(player.getName(), scale), e);
             }
         }
 

bukkit/src/main/java/net/william278/husksync/data/BukkitSerializer.java

@@ -29,6 +29,7 @@ import de.tr7zw.changeme.nbtapi.utils.DataFixerUtil;
 import lombok.AccessLevel;
 import lombok.AllArgsConstructor;
 import net.william278.desertwell.util.Version;
+import net.william278.husksync.BukkitHuskSync;
 import net.william278.husksync.HuskSync;
 import net.william278.husksync.adapter.Adaptable;
 import net.william278.husksync.api.HuskSyncAPI;
@@ -41,6 +42,8 @@ import org.jetbrains.annotations.Nullable;
 import java.util.List;
 
 import static net.william278.husksync.data.BukkitData.Items.Inventory.INVENTORY_SLOT_COUNT;
+import static net.william278.husksync.data.Data.Items.Inventory.HELD_ITEM_SLOT_TAG;
+import static net.william278.husksync.data.Data.Items.Inventory.ITEMS_TAG;
 
 @AllArgsConstructor(access = AccessLevel.PRIVATE)
 public class BukkitSerializer {
@@ -60,8 +63,6 @@ public class BukkitSerializer {
 
     public static class Inventory extends BukkitSerializer implements Serializer<BukkitData.Items.Inventory>,
             ItemDeserializer {
-        private static final String ITEMS_TAG = "items";
-        private static final String HELD_ITEM_SLOT_TAG = "held_item_slot";
 
         public Inventory(@NotNull HuskSync plugin) {
             super(plugin);
@@ -74,7 +75,7 @@ public class BukkitSerializer {
             final ReadWriteNBT items = root.hasTag(ITEMS_TAG) ? root.getCompound(ITEMS_TAG) : null;
             return BukkitData.Items.Inventory.from(
                     items != null ? getItems(items, dataMcVersion) : new ItemStack[INVENTORY_SLOT_COUNT],
-                    root.getInteger(HELD_ITEM_SLOT_TAG)
+                    root.hasTag(HELD_ITEM_SLOT_TAG) ? root.getInteger(HELD_ITEM_SLOT_TAG) : 0
             );
         }
 
@@ -126,15 +127,15 @@ public class BukkitSerializer {
         @Nullable
         default ItemStack[] getItems(@NotNull ReadWriteNBT tag, @NotNull Version mcVersion) {
             if (mcVersion.compareTo(getPlugin().getMinecraftVersion()) < 0) {
-                return upgradeItemStack((NBTCompound) tag, mcVersion);
+                return upgradeItemStacks((NBTCompound) tag, mcVersion);
             }
             return NBT.itemStackArrayFromNBT(tag);
         }
 
         @NotNull
-        private ItemStack @NotNull [] upgradeItemStack(@NotNull NBTCompound compound, @NotNull Version mcVersion) {
-            final ReadWriteNBTCompoundList items = compound.getCompoundList("items");
-            final ItemStack[] itemStacks = new ItemStack[compound.getInteger("size")];
+        private ItemStack @NotNull [] upgradeItemStacks(@NotNull NBTCompound itemsNbt, @NotNull Version mcVersion) {
+            final ReadWriteNBTCompoundList items = itemsNbt.getCompoundList("items");
+            final ItemStack[] itemStacks = new ItemStack[itemsNbt.getInteger("size")];
             for (int i = 0; i < items.size(); i++) {
                 if (items.get(i) == null) {
                     itemStacks[i] = new ItemStack(Material.AIR);
@@ -163,6 +164,8 @@ public class BukkitSerializer {
                 case "1.19", "1.19.1", "1.19.2" -> DataFixerUtil.VERSION1_19_2;
                 case "1.20", "1.20.1", "1.20.2" -> DataFixerUtil.VERSION1_20_2;
                 case "1.20.3", "1.20.4" -> DataFixerUtil.VERSION1_20_4;
+                case "1.20.5", "1.20.6" -> DataFixerUtil.VERSION1_20_5;
+                case "1.21" -> DataFixerUtil.VERSION1_21;
                 default -> DataFixerUtil.getCurrentVersion();
             };
         }
@@ -237,24 +240,19 @@ public class BukkitSerializer {
 
     }
 
-    public static class Json<T extends Data & Adaptable> extends BukkitSerializer implements Serializer<T> {
+    /**
+     * @deprecated Use {@link Serializer.Json} in the common module instead
+     */
+    @Deprecated(since = "2.6")
+    public class Json<T extends Data & Adaptable> extends Serializer.Json<T> {
 
-        private final Class<T> type;
-
-        public Json(@NotNull HuskSync plugin, Class<T> type) {
-            super(plugin);
-            this.type = type;
-        }
-
-        @Override
-        public T deserialize(@NotNull String serialized) throws DeserializationException {
-            return plugin.getDataAdapter().fromJson(serialized, type);
+        public Json(@NotNull HuskSync plugin, @NotNull Class<T> type) {
+            super(plugin, type);
         }
 
         @NotNull
-        @Override
-        public String serialize(@NotNull T element) throws SerializationException {
-            return plugin.getDataAdapter().toJson(element);
+        public BukkitHuskSync getPlugin() {
+            return (BukkitHuskSync) plugin;
         }
 
     }

bukkit/src/main/java/net/william278/husksync/data/BukkitUserDataHolder.java

@@ -67,9 +67,9 @@ public interface BukkitUserDataHolder extends UserDataHolder {
                 .isSyncDeadPlayersChangingServer())) {
             return Optional.of(BukkitData.Items.Inventory.empty());
         }
-        final PlayerInventory inventory = getBukkitPlayer().getInventory();
+        final PlayerInventory inventory = getPlayer().getInventory();
         return Optional.of(BukkitData.Items.Inventory.from(
-                getMapPersister().persistLockedMaps(inventory.getContents(), getBukkitPlayer()),
+                getMapPersister().persistLockedMaps(inventory.getContents(), getPlayer()),
                 inventory.getHeldItemSlot()
         ));
     }
@@ -78,80 +78,89 @@ public interface BukkitUserDataHolder extends UserDataHolder {
     @Override
     default Optional<Data.Items.EnderChest> getEnderChest() {
         return Optional.of(BukkitData.Items.EnderChest.adapt(
-                getMapPersister().persistLockedMaps(getBukkitPlayer().getEnderChest().getContents(), getBukkitPlayer())
+                getMapPersister().persistLockedMaps(getPlayer().getEnderChest().getContents(), getPlayer())
         ));
     }
 
     @NotNull
     @Override
     default Optional<Data.PotionEffects> getPotionEffects() {
-        return Optional.of(BukkitData.PotionEffects.from(getBukkitPlayer().getActivePotionEffects()));
+        return Optional.of(BukkitData.PotionEffects.from(getPlayer().getActivePotionEffects()));
     }
 
     @NotNull
     @Override
     default Optional<Data.Advancements> getAdvancements() {
-        return Optional.of(BukkitData.Advancements.adapt(getBukkitPlayer()));
+        return Optional.of(BukkitData.Advancements.adapt(getPlayer()));
     }
 
     @NotNull
     @Override
     default Optional<Data.Location> getLocation() {
-        return Optional.of(BukkitData.Location.adapt(getBukkitPlayer().getLocation()));
+        return Optional.of(BukkitData.Location.adapt(getPlayer().getLocation()));
     }
 
     @NotNull
     @Override
     default Optional<Data.Statistics> getStatistics() {
-        return Optional.of(BukkitData.Statistics.adapt(getBukkitPlayer()));
+        return Optional.of(BukkitData.Statistics.adapt(getPlayer()));
     }
 
     @NotNull
     @Override
     default Optional<Data.Health> getHealth() {
-        return Optional.of(BukkitData.Health.adapt(getBukkitPlayer()));
+        return Optional.of(BukkitData.Health.adapt(getPlayer()));
     }
 
     @NotNull
     @Override
     default Optional<Data.Hunger> getHunger() {
-        return Optional.of(BukkitData.Hunger.adapt(getBukkitPlayer()));
+        return Optional.of(BukkitData.Hunger.adapt(getPlayer()));
     }
 
     @NotNull
     @Override
     default Optional<Data.Attributes> getAttributes() {
-        return Optional.of(BukkitData.Attributes.adapt(getBukkitPlayer(), getPlugin()));
+        return Optional.of(BukkitData.Attributes.adapt(getPlayer(), getPlugin()));
     }
 
     @NotNull
     @Override
     default Optional<Data.Experience> getExperience() {
-        return Optional.of(BukkitData.Experience.adapt(getBukkitPlayer()));
+        return Optional.of(BukkitData.Experience.adapt(getPlayer()));
     }
 
     @NotNull
     @Override
     default Optional<Data.GameMode> getGameMode() {
-        return Optional.of(BukkitData.GameMode.adapt(getBukkitPlayer()));
+        return Optional.of(BukkitData.GameMode.adapt(getPlayer()));
     }
 
     @NotNull
     @Override
     default Optional<Data.FlightStatus> getFlightStatus() {
-        return Optional.of(BukkitData.FlightStatus.adapt(getBukkitPlayer()));
+        return Optional.of(BukkitData.FlightStatus.adapt(getPlayer()));
     }
 
     @NotNull
     @Override
     default Optional<Data.PersistentData> getPersistentData() {
-        return Optional.of(BukkitData.PersistentData.adapt(getBukkitPlayer().getPersistentDataContainer()));
+        return Optional.of(BukkitData.PersistentData.adapt(getPlayer().getPersistentDataContainer()));
     }
 
     boolean isDead();
 
     @NotNull
-    Player getBukkitPlayer();
+    Player getPlayer();
+
+    /**
+     * @deprecated Use {@link #getPlayer()} instead
+     */
+    @Deprecated(since = "3.6")
+    @NotNull
+    default Player getBukkitPlayer() {
+        return getPlayer();
+    }
 
     @NotNull
     default BukkitMapPersister getMapPersister() {

bukkit/src/main/java/net/william278/husksync/listener/BukkitEventListener.java

@@ -20,7 +20,6 @@
 package net.william278.husksync.listener;
 
 import net.william278.husksync.BukkitHuskSync;
-import net.william278.husksync.HuskSync;
 import net.william278.husksync.data.BukkitData;
 import net.william278.husksync.user.BukkitUser;
 import net.william278.husksync.user.OnlineUser;
@@ -40,21 +39,38 @@ import java.util.stream.Collectors;
 public class BukkitEventListener extends EventListener implements BukkitJoinEventListener, BukkitQuitEventListener,
         BukkitDeathEventListener, Listener {
 
-    protected final LockedHandler lockedHandler;
+    protected LockedHandler lockedHandler;
 
     public BukkitEventListener(@NotNull BukkitHuskSync plugin) {
         super(plugin);
-        plugin.getServer().getPluginManager().registerEvents(this, plugin);
-        this.lockedHandler = createLockedHandler(plugin);
+    }
+
+    public void onLoad() {
+        this.lockedHandler = createLockedHandler((BukkitHuskSync) plugin);
+    }
+
+    public void onEnable() {
+        getPlugin().getServer().getPluginManager().registerEvents(this, getPlugin());
+        lockedHandler.onEnable();
+    }
+
+    public void handlePluginDisable() {
+        super.handlePluginDisable();
+        lockedHandler.onDisable();
     }
 
     @NotNull
     private LockedHandler createLockedHandler(@NotNull BukkitHuskSync plugin) {
-        if (getPlugin().isDependencyLoaded("ProtocolLib") && getPlugin().getSettings().isCancelPackets()) {
-            return new BukkitLockedPacketListener(plugin);
-        } else {
+        if (!getPlugin().getSettings().isCancelPackets()) {
             return new BukkitLockedEventListener(plugin);
         }
+        if (getPlugin().isDependencyLoaded("PacketEvents")) {
+            return new BukkitPacketEventsLockedPacketListener(plugin);
+        } else if (getPlugin().isDependencyLoaded("ProtocolLib")) {
+            return new BukkitProtocolLibLockedPacketListener(plugin);
+        }
+
+        return new BukkitLockedEventListener(plugin);
     }
 
     @Override
@@ -134,8 +150,8 @@ public class BukkitEventListener extends EventListener implements BukkitJoinEven
 
     @NotNull
     @Override
-    public HuskSync getPlugin() {
-        return plugin;
+    public BukkitHuskSync getPlugin() {
+        return (BukkitHuskSync) plugin;
     }
 
 }

bukkit/src/main/java/net/william278/husksync/listener/BukkitLockedEventListener.java

@@ -50,6 +50,10 @@ public class BukkitLockedEventListener implements LockedHandler, Listener {
 
     protected BukkitLockedEventListener(@NotNull BukkitHuskSync plugin) {
         this.plugin = plugin;
+    }
+
+    @Override
+    public void onEnable() {
         plugin.getServer().getPluginManager().registerEvents(this, plugin);
     }
 

bukkit/src/main/java/net/william278/husksync/listener/BukkitPacketEventsLockedPacketListener.java

@@ -0,0 +1,103 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.listener;
+
+import com.github.retrooper.packetevents.PacketEvents;
+import com.github.retrooper.packetevents.event.PacketListenerAbstract;
+import com.github.retrooper.packetevents.event.PacketListenerPriority;
+import com.github.retrooper.packetevents.event.PacketReceiveEvent;
+import com.github.retrooper.packetevents.protocol.packettype.PacketType;
+import com.google.common.collect.Sets;
+import io.github.retrooper.packetevents.factory.spigot.SpigotPacketEventsBuilder;
+import net.william278.husksync.BukkitHuskSync;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Set;
+import java.util.logging.Level;
+
+public class BukkitPacketEventsLockedPacketListener extends BukkitLockedEventListener implements LockedHandler {
+
+    protected BukkitPacketEventsLockedPacketListener(@NotNull BukkitHuskSync plugin) {
+        super(plugin);
+    }
+
+    @Override
+    public void onLoad() {
+        super.onLoad();
+        PacketEvents.setAPI(SpigotPacketEventsBuilder.build(getPlugin()));
+        PacketEvents.getAPI().getSettings().reEncodeByDefault(false)
+                .checkForUpdates(false)
+                .bStats(true);
+        PacketEvents.getAPI().load();
+    }
+
+    @Override
+    public void onEnable() {
+        super.onEnable();
+        PacketEvents.getAPI().getEventManager().registerListener(new PlayerPacketAdapter(this));
+        PacketEvents.getAPI().init();
+        plugin.log(Level.INFO, "Using PacketEvents to cancel packets for locked players");
+    }
+
+    private static class PlayerPacketAdapter extends PacketListenerAbstract {
+
+        private static final Set<PacketType.Play.Client> ALLOWED_PACKETS = Set.of(
+                PacketType.Play.Client.KEEP_ALIVE, PacketType.Play.Client.PONG, PacketType.Play.Client.PLUGIN_MESSAGE, // Connection packets
+                PacketType.Play.Client.CHAT_MESSAGE, PacketType.Play.Client.CHAT_COMMAND, PacketType.Play.Client.CHAT_SESSION_UPDATE, // Chat / command packets
+                PacketType.Play.Client.PLAYER_POSITION, PacketType.Play.Client.PLAYER_POSITION_AND_ROTATION, PacketType.Play.Client.PLAYER_ROTATION, // Movement packets
+                PacketType.Play.Client.HELD_ITEM_CHANGE, PacketType.Play.Client.ANIMATION, PacketType.Play.Client.TELEPORT_CONFIRM, // Animation packets
+                PacketType.Play.Client.CLIENT_SETTINGS // Video setting packets
+        );
+
+        private static final Set<PacketType.Play.Client> CANCEL_PACKETS = getPacketsToListenFor();
+
+
+        private final BukkitPacketEventsLockedPacketListener listener;
+
+        public PlayerPacketAdapter(@NotNull BukkitPacketEventsLockedPacketListener listener) {
+            super(PacketListenerPriority.HIGH);
+            this.listener = listener;
+        }
+
+        @Override
+        public void onPacketReceive(PacketReceiveEvent event) {
+            if(!(event.getPacketType() instanceof PacketType.Play.Client client)) {
+                return;
+            }
+            if (!CANCEL_PACKETS.contains(client)) {
+                return;
+            }
+            if (listener.cancelPlayerEvent(event.getUser().getUUID())) {
+                event.setCancelled(true);
+            }
+        }
+
+        // Returns the set of ALL Server packets, excluding the set of allowed packets
+        @NotNull
+        private static Set<PacketType.Play.Client> getPacketsToListenFor() {
+            return Sets.difference(
+                    Sets.newHashSet(PacketType.Play.Client.values()),
+                    ALLOWED_PACKETS
+            );
+        }
+
+    }
+
+}

bukkit/src/main/java/net/william278/husksync/listener/BukkitProtocolLibLockedPacketListener.java

@@ -34,10 +34,15 @@ import java.util.stream.Collectors;
 
 import static com.comphenix.protocol.PacketType.Play.Client;
 
-public class BukkitLockedPacketListener extends BukkitLockedEventListener implements LockedHandler {
+public class BukkitProtocolLibLockedPacketListener extends BukkitLockedEventListener implements LockedHandler {
 
-    protected BukkitLockedPacketListener(@NotNull BukkitHuskSync plugin) {
+    protected BukkitProtocolLibLockedPacketListener(@NotNull BukkitHuskSync plugin) {
         super(plugin);
+    }
+
+    @Override
+    public void onEnable() {
+        super.onEnable();
         ProtocolLibrary.getProtocolManager().addPacketListener(new PlayerPacketAdapter(this));
         plugin.log(Level.INFO, "Using ProtocolLib to cancel packets for locked players");
     }
@@ -53,9 +58,9 @@ public class BukkitLockedPacketListener extends BukkitLockedEventListener implem
                 Client.SETTINGS // Video setting packets
         );
 
-        private final BukkitLockedPacketListener listener;
+        private final BukkitProtocolLibLockedPacketListener listener;
 
-        public PlayerPacketAdapter(@NotNull BukkitLockedPacketListener listener) {
+        public PlayerPacketAdapter(@NotNull BukkitProtocolLibLockedPacketListener listener) {
             super(listener.getPlugin(), ListenerPriority.HIGHEST, getPacketsToListenFor());
             this.listener = listener;
         }

bukkit/src/main/java/net/william278/husksync/migrator/LegacyMigrator.java

@@ -330,7 +330,7 @@ public class LegacyMigrator extends Migrator {
                         ))
 
                         // Health, hunger, experience & game mode
-                        .health(BukkitData.Health.from(health, healthScale))
+                        .health(BukkitData.Health.from(health, healthScale, false))
                         .hunger(BukkitData.Hunger.from(hunger, saturation, saturationExhaustion))
                         .experience(BukkitData.Experience.from(totalExp, expLevel, expProgress))
                         .gameMode(BukkitData.GameMode.from(gameMode))

bukkit/src/main/java/net/william278/husksync/user/BukkitUser.java

@@ -62,17 +62,6 @@ public class BukkitUser extends OnlineUser implements BukkitUserDataHolder {
         return new BukkitUser(player, plugin);
     }
 
-    /**
-     * Get the Bukkit {@link Player} instance of this user
-     *
-     * @return the {@link Player} instance
-     * @since 3.0
-     */
-    @NotNull
-    public Player getPlayer() {
-        return player;
-    }
-
     @Override
     public boolean isOffline() {
         return player == null || !player.isOnline();
@@ -132,9 +121,14 @@ public class BukkitUser extends OnlineUser implements BukkitUserDataHolder {
         return player.hasMetadata("NPC");
     }
 
+    /**
+     * Get the Bukkit {@link Player} instance of this user
+     *
+     * @return the {@link Player} instance
+     * @since 3.6
+     */
     @NotNull
-    @Override
-    public Player getBukkitPlayer() {
+    public Player getPlayer() {
         return player;
     }
 

bukkit/src/main/java/net/william278/husksync/util/BukkitKeyedAdapter.java

@@ -19,38 +19,44 @@
 
 package net.william278.husksync.util;
 
-import org.bukkit.Material;
-import org.bukkit.NamespacedKey;
-import org.bukkit.Registry;
-import org.bukkit.Statistic;
+import org.bukkit.*;
 import org.bukkit.attribute.Attribute;
 import org.bukkit.entity.EntityType;
+import org.bukkit.potion.PotionEffectType;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
-import java.util.Objects;
-
 // Utility class for adapting "Keyed" Bukkit objects
 public final class BukkitKeyedAdapter {
 
     @Nullable
     public static Statistic matchStatistic(@NotNull String key) {
-        return Registry.STATISTIC.get(Objects.requireNonNull(NamespacedKey.fromString(key), "Null key"));
+        return getRegistryValue(Registry.STATISTIC, key);
     }
 
     @Nullable
     public static EntityType matchEntityType(@NotNull String key) {
-        return Registry.ENTITY_TYPE.get(Objects.requireNonNull(NamespacedKey.fromString(key), "Null key"));
+        return getRegistryValue(Registry.ENTITY_TYPE, key);
     }
 
     @Nullable
     public static Material matchMaterial(@NotNull String key) {
-        return Registry.MATERIAL.get(Objects.requireNonNull(NamespacedKey.fromString(key), "Null key"));
+        return getRegistryValue(Registry.MATERIAL, key);
     }
 
     @Nullable
     public static Attribute matchAttribute(@NotNull String key) {
-        return Registry.ATTRIBUTE.get(Objects.requireNonNull(NamespacedKey.fromString(key), "Null key"));
+        return getRegistryValue(Registry.ATTRIBUTE, key);
+    }
+
+    @Nullable
+    public static PotionEffectType matchEffectType(@NotNull String key) {
+        return PotionEffectType.getByName(key); // No registry for this in 1.17 API
+    }
+
+    private static <T extends Keyed> T getRegistryValue(@NotNull Registry<T> registry, @NotNull String keyString) {
+        final NamespacedKey key = NamespacedKey.fromString(keyString);
+        return key != null ? registry.get(key) : null;
     }
 
 }

bukkit/src/main/java/net/william278/husksync/util/BukkitLegacyConverter.java

@@ -82,32 +82,33 @@ public class BukkitLegacyConverter extends LegacyConverter {
 
         final JSONObject status = object.getJSONObject("status_data");
         final HashMap<Identifier, Data> containers = Maps.newHashMap();
-        if (shouldImport(Identifier.HEALTH)) {
+        if (Identifier.HEALTH.isEnabled()) {
             containers.put(Identifier.HEALTH, BukkitData.Health.from(
                     status.getDouble("health"),
-                    status.getDouble("health_scale")
+                    status.getDouble("health_scale"),
+                    false
             ));
         }
-        if (shouldImport(Identifier.HUNGER)) {
+        if (Identifier.HUNGER.isEnabled()) {
             containers.put(Identifier.HUNGER, BukkitData.Hunger.from(
                     status.getInt("hunger"),
                     status.getFloat("saturation"),
                     status.getFloat("saturation_exhaustion")
             ));
         }
-        if (shouldImport(Identifier.EXPERIENCE)) {
+        if (Identifier.EXPERIENCE.isEnabled()) {
             containers.put(Identifier.EXPERIENCE, BukkitData.Experience.from(
                     status.getInt("total_experience"),
                     status.getInt("experience_level"),
                     status.getFloat("experience_progress")
             ));
         }
-        if (shouldImport(Identifier.GAME_MODE)) {
+        if (Identifier.GAME_MODE.isEnabled()) {
             containers.put(Identifier.GAME_MODE, BukkitData.GameMode.from(
                     status.getString("game_mode")
             ));
         }
-        if (shouldImport(Identifier.FLIGHT_STATUS)) {
+        if (Identifier.FLIGHT_STATUS.isEnabled()) {
             containers.put(Identifier.FLIGHT_STATUS, BukkitData.FlightStatus.from(
                     status.getBoolean("is_flying"),
                     status.getBoolean("is_flying")
@@ -118,7 +119,7 @@ public class BukkitLegacyConverter extends LegacyConverter {
 
     @NotNull
     private Optional<Data.Items.Inventory> readInventory(@NotNull JSONObject object) {
-        if (!object.has("inventory") || !shouldImport(Identifier.INVENTORY)) {
+        if (!object.has("inventory") || !Identifier.INVENTORY.isEnabled()) {
             return Optional.empty();
         }
 
@@ -130,7 +131,7 @@ public class BukkitLegacyConverter extends LegacyConverter {
 
     @NotNull
     private Optional<Data.Items.EnderChest> readEnderChest(@NotNull JSONObject object) {
-        if (!object.has("ender_chest") || !shouldImport(Identifier.ENDER_CHEST)) {
+        if (!object.has("ender_chest") || !Identifier.ENDER_CHEST.isEnabled()) {
             return Optional.empty();
         }
 
@@ -142,7 +143,7 @@ public class BukkitLegacyConverter extends LegacyConverter {
 
     @NotNull
     private Optional<Data.Location> readLocation(@NotNull JSONObject object) {
-        if (!object.has("location") || !shouldImport(Identifier.LOCATION)) {
+        if (!object.has("location") || !Identifier.LOCATION.isEnabled()) {
             return Optional.empty();
         }
 
@@ -163,7 +164,7 @@ public class BukkitLegacyConverter extends LegacyConverter {
 
     @NotNull
     private Optional<Data.Advancements> readAdvancements(@NotNull JSONObject object) {
-        if (!object.has("advancements") || !shouldImport(Identifier.ADVANCEMENTS)) {
+        if (!object.has("advancements") || !Identifier.ADVANCEMENTS.isEnabled()) {
             return Optional.empty();
         }
 
@@ -186,7 +187,7 @@ public class BukkitLegacyConverter extends LegacyConverter {
 
     @NotNull
     private Optional<Data.Statistics> readStatistics(@NotNull JSONObject object) {
-        if (!object.has("statistics") || !shouldImport(Identifier.STATISTICS)) {
+        if (!object.has("statistics") || !Identifier.STATISTICS.isEnabled()) {
             return Optional.empty();
         }
 
@@ -280,11 +281,6 @@ public class BukkitLegacyConverter extends LegacyConverter {
         return serializedItemStack != null ? ItemStack.deserialize((Map<String, Object>) serializedItemStack) : null;
     }
 
-
-    private boolean shouldImport(@NotNull Identifier type) {
-        return plugin.getSettings().getSynchronization().isFeatureEnabled(type);
-    }
-
     @NotNull
     private Date parseDate(@NotNull String dateString) {
         try {

bukkit/src/main/java/net/william278/husksync/util/BukkitMapPersister.java

@@ -31,8 +31,10 @@ import net.william278.mapdataapi.MapData;
 import org.bukkit.Bukkit;
 import org.bukkit.Material;
 import org.bukkit.World;
+import org.bukkit.block.ShulkerBox;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.meta.BlockStateMeta;
 import org.bukkit.inventory.meta.MapMeta;
 import org.bukkit.map.*;
 import org.jetbrains.annotations.ApiStatus;
@@ -94,6 +96,9 @@ public interface BukkitMapPersister {
             }
             if (item.getType() == Material.FILLED_MAP && item.hasItemMeta()) {
                 items[i] = function.apply(item);
+            } else if (item.getItemMeta() instanceof BlockStateMeta b && b.getBlockState() instanceof ShulkerBox box) {
+                forEachMap(box.getInventory().getContents(), function);
+                b.setBlockState(box);
             }
         }
         return items;
@@ -150,8 +155,8 @@ public interface BukkitMapPersister {
             Optional<String> world = Optional.empty();
             for (String worldUid : mapIds.getKeys()) {
                 world = getPlugin().getServer().getWorlds().stream()
-                        .map(w -> w.getUID().toString()).filter(u -> u.equals(worldUid))
-                        .findFirst();
+                    .map(w -> w.getUID().toString()).filter(u -> u.equals(worldUid))
+                    .findFirst();
                 if (world.isPresent()) {
                     break;
                 }
@@ -174,7 +179,7 @@ public interface BukkitMapPersister {
             try {
                 getPlugin().debug("Deserializing map data from NBT and generating view...");
                 canvasData = MapData.fromByteArray(Objects.requireNonNull(mapData.getByteArray(MAP_PIXEL_DATA_KEY),
-                        "Map pixel data is null"));
+                    "Map pixel data is null"));
             } catch (Throwable e) {
                 getPlugin().log(Level.WARNING, "Failed to deserialize map data from NBT", e);
                 return;
@@ -190,8 +195,8 @@ public interface BukkitMapPersister {
             // Set the map view ID in NBT
             NBT.modify(map, editable -> {
                 Objects.requireNonNull(editable.getCompound(MAP_VIEW_ID_MAPPINGS_KEY),
-                                "Map view ID mappings compound is null")
-                        .setInteger(worldUid, view.getId());
+                        "Map view ID mappings compound is null")
+                    .setInteger(worldUid, view.getId());
             });
             getPlugin().debug(String.format("Generated view (#%s) and updated map (UID: %s)", view.getId(), worldUid));
         });
@@ -321,29 +326,29 @@ public interface BukkitMapPersister {
     @NotNull
     private static MapCursor createBannerCursor(@NotNull MapBanner banner) {
         return new MapCursor(
-                (byte) banner.getPosition().getX(),
-                (byte) banner.getPosition().getZ(),
-                (byte) 8, // Always rotate banners upright
-                switch (banner.getColor().toLowerCase(Locale.ENGLISH)) {
-                    case "white" -> MapCursor.Type.BANNER_WHITE;
-                    case "orange" -> MapCursor.Type.BANNER_ORANGE;
-                    case "magenta" -> MapCursor.Type.BANNER_MAGENTA;
-                    case "light_blue" -> MapCursor.Type.BANNER_LIGHT_BLUE;
-                    case "yellow" -> MapCursor.Type.BANNER_YELLOW;
-                    case "lime" -> MapCursor.Type.BANNER_LIME;
-                    case "pink" -> MapCursor.Type.BANNER_PINK;
-                    case "gray" -> MapCursor.Type.BANNER_GRAY;
-                    case "light_gray" -> MapCursor.Type.BANNER_LIGHT_GRAY;
-                    case "cyan" -> MapCursor.Type.BANNER_CYAN;
-                    case "purple" -> MapCursor.Type.BANNER_PURPLE;
-                    case "blue" -> MapCursor.Type.BANNER_BLUE;
-                    case "brown" -> MapCursor.Type.BANNER_BROWN;
-                    case "green" -> MapCursor.Type.BANNER_GREEN;
-                    case "red" -> MapCursor.Type.BANNER_RED;
-                    default -> MapCursor.Type.BANNER_BLACK;
-                },
-                true,
-                banner.getText().isEmpty() ? null : banner.getText()
+            (byte) banner.getPosition().getX(),
+            (byte) banner.getPosition().getZ(),
+            (byte) 8, // Always rotate banners upright
+            switch (banner.getColor().toLowerCase(Locale.ENGLISH)) {
+                case "white" -> MapCursor.Type.BANNER_WHITE;
+                case "orange" -> MapCursor.Type.BANNER_ORANGE;
+                case "magenta" -> MapCursor.Type.BANNER_MAGENTA;
+                case "light_blue" -> MapCursor.Type.BANNER_LIGHT_BLUE;
+                case "yellow" -> MapCursor.Type.BANNER_YELLOW;
+                case "lime" -> MapCursor.Type.BANNER_LIME;
+                case "pink" -> MapCursor.Type.BANNER_PINK;
+                case "gray" -> MapCursor.Type.BANNER_GRAY;
+                case "light_gray" -> MapCursor.Type.BANNER_LIGHT_GRAY;
+                case "cyan" -> MapCursor.Type.BANNER_CYAN;
+                case "purple" -> MapCursor.Type.BANNER_PURPLE;
+                case "blue" -> MapCursor.Type.BANNER_BLUE;
+                case "brown" -> MapCursor.Type.BANNER_BROWN;
+                case "green" -> MapCursor.Type.BANNER_GREEN;
+                case "red" -> MapCursor.Type.BANNER_RED;
+                default -> MapCursor.Type.BANNER_BLACK;
+            },
+            true,
+            banner.getText().isEmpty() ? null : banner.getText()
         );
     }
 
@@ -425,11 +430,11 @@ public interface BukkitMapPersister {
                 final String type = cursor.getType().name().toLowerCase(Locale.ENGLISH);
                 if (type.startsWith(BANNER_PREFIX)) {
                     banners.add(new MapBanner(
-                            type.replaceAll(BANNER_PREFIX, ""),
-                            cursor.getCaption() == null ? "" : cursor.getCaption(),
-                            cursor.getX(),
-                            mapView.getWorld() != null ? mapView.getWorld().getSeaLevel() : 128,
-                            cursor.getY()
+                        type.replaceAll(BANNER_PREFIX, ""),
+                        cursor.getCaption() == null ? "" : cursor.getCaption(),
+                        cursor.getX(),
+                        mapView.getWorld() != null ? mapView.getWorld().getSeaLevel() : 128,
+                        cursor.getY()
                     ));
                 }
             }

bukkit/src/main/resources/commodore/enderchest.commodore

@@ -1,3 +0,0 @@
-inventory {
-  name brigadier:string single_word;
-}

bukkit/src/main/resources/commodore/husksync.commodore

@@ -1,6 +0,0 @@
-husksync {
-  update;
-  about;
-  status;
-  reload;
-}

bukkit/src/main/resources/commodore/inventory.commodore

@@ -1,3 +0,0 @@
-enderchest {
-  name brigadier:string single_word;
-}

bukkit/src/main/resources/commodore/userdata.commodore

@@ -1,35 +0,0 @@
-userdata {
-  view {
-    name brigadier:string single_word {
-      version brigadier:string single_word;
-    }
-  }
-  list {
-    name brigadier:string single_word {
-      page brigadier:integer;
-    }
-  }
-  delete {
-    name brigadier:string single_word {
-      version brigadier:string single_word;
-    }
-  }
-  restore {
-    name brigadier:string single_word {
-      version brigadier:string single_word;
-    }
-  }
-  pin {
-    name brigadier:string single_word {
-      version brigadier:string single_word;
-    }
-  }
-  dump {
-    name brigadier:string single_word {
-      version brigadier:string single_word {
-        web;
-        file;
-      }
-    }
-  }
-}

bukkit/src/main/resources/plugin.yml

@@ -7,6 +7,7 @@ description: '${description}'
 website: 'https://william278.net'
 folia-supported: true
 softdepend:
+  - 'packetevents'
   - 'ProtocolLib'
   - 'MysqlPlayerDataBridge'
   - 'Plan'

common/build.gradle

@@ -7,7 +7,7 @@ dependencies {
     api 'org.apache.commons:commons-text:1.12.0'
     api 'net.william278:minedown:1.8.2'
     api 'org.json:json:20240303'
-    api 'com.google.code.gson:gson:2.10.1'
+    api 'com.google.code.gson:gson:2.11.0'
     api 'com.fatboyindustrial.gson-javatime-serialisers:gson-javatime-serialisers:1.1.2'
     api 'de.exlll:configlib-yaml:4.5.0'
     api 'net.william278:paginedown:1.1.2'
@@ -16,11 +16,13 @@ dependencies {
         exclude module: 'slf4j-api'
     }
 
+    compileOnly 'net.william278.uniform:uniform-common:1.1.8'
+    compileOnly 'com.mojang:brigadier:1.1.8'
     compileOnly 'org.projectlombok:lombok:1.18.32'
     compileOnly 'org.jetbrains:annotations:24.1.0'
-    compileOnly 'net.kyori:adventure-api:4.16.0'
-    compileOnly 'net.kyori:adventure-platform-api:4.3.2'
-    compileOnly 'com.google.guava:guava:33.2.0-jre'
+    compileOnly 'net.kyori:adventure-api:4.17.0'
+    compileOnly 'net.kyori:adventure-platform-api:4.3.3'
+    compileOnly 'com.google.guava:guava:33.2.1-jre'
     compileOnly 'com.github.plan-player-analytics:Plan:5.5.2272'
     compileOnly "redis.clients:jedis:$jedis_version"
     compileOnly "com.mysql:mysql-connector-j:$mysql_driver_version"
@@ -31,7 +33,7 @@ dependencies {
 
     testImplementation "redis.clients:jedis:$jedis_version"
     testImplementation "org.xerial.snappy:snappy-java:$snappy_version"
-    testImplementation 'com.google.guava:guava:33.2.0-jre'
+    testImplementation 'com.google.guava:guava:33.2.1-jre'
     testImplementation 'com.github.plan-player-analytics:Plan:5.5.2272'
     testCompileOnly 'de.exlll:configlib-yaml:4.5.0'
     testCompileOnly 'org.jetbrains:annotations:24.1.0'

common/src/main/java/net/william278/husksync/HuskSync.java

@@ -31,7 +31,7 @@ import net.william278.husksync.adapter.DataAdapter;
 import net.william278.husksync.config.ConfigProvider;
 import net.william278.husksync.data.Data;
 import net.william278.husksync.data.Identifier;
-import net.william278.husksync.data.Serializer;
+import net.william278.husksync.data.SerializerRegistry;
 import net.william278.husksync.database.Database;
 import net.william278.husksync.event.EventDispatcher;
 import net.william278.husksync.migrator.Migrator;
@@ -41,9 +41,9 @@ import net.william278.husksync.user.ConsoleUser;
 import net.william278.husksync.user.OnlineUser;
 import net.william278.husksync.util.LegacyConverter;
 import net.william278.husksync.util.Task;
+import net.william278.uniform.Uniform;
 import org.jetbrains.annotations.NotNull;
 
-import java.io.File;
 import java.io.InputStream;
 import java.text.SimpleDateFormat;
 import java.util.*;
@@ -52,7 +52,7 @@ import java.util.logging.Level;
 /**
  * Abstract implementation of the HuskSync plugin.
  */
-public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider {
+public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider, SerializerRegistry {
 
     int SPIGOT_RESOURCE_ID = 97144;
 
@@ -86,7 +86,6 @@ public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider
      *
      * @return the {@link RedisManager} implementation
      */
-
     @NotNull
     RedisManager getRedisManager();
 
@@ -98,43 +97,6 @@ public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider
     @NotNull
     DataAdapter getDataAdapter();
 
-    /**
-     * Returns the data serializer for the given {@link Identifier}
-     */
-    @NotNull
-    <T extends Data> Map<Identifier, Serializer<T>> getSerializers();
-
-    /**
-     * Register a data serializer for the given {@link Identifier}
-     *
-     * @param identifier the {@link Identifier}
-     * @param serializer the {@link Serializer}
-     */
-    default void registerSerializer(@NotNull Identifier identifier,
-                                    @NotNull Serializer<? extends Data> serializer) {
-        if (identifier.isCustom()) {
-            log(Level.INFO, String.format("Registered custom data type: %s", identifier));
-        }
-        getSerializers().put(identifier, (Serializer<Data>) serializer);
-    }
-
-    /**
-     * Get the {@link Identifier} for the given key
-     */
-    default Optional<Identifier> getIdentifier(@NotNull String key) {
-        return getSerializers().keySet().stream().filter(identifier -> identifier.toString().equals(key)).findFirst();
-    }
-
-    /**
-     * Get the set of registered data types
-     *
-     * @return the set of registered data types
-     */
-    @NotNull
-    default Set<Identifier> getRegisteredDataTypes() {
-        return getSerializers().keySet();
-    }
-
     /**
      * Returns the data syncer implementation
      *
@@ -150,6 +112,14 @@ public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider
      */
     void setDataSyncer(@NotNull DataSyncer dataSyncer);
 
+    /**
+     * Get the uniform command provider
+     *
+     * @return the command provider
+     */
+    @NotNull
+    Uniform getUniform();
+
     /**
      * Returns a list of available data {@link Migrator}s
      *
@@ -159,7 +129,17 @@ public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider
     List<Migrator> getAvailableMigrators();
 
     @NotNull
-    Map<Identifier, Data> getPlayerCustomDataStore(@NotNull OnlineUser user);
+    Map<UUID, Map<Identifier, Data>> getPlayerCustomDataStore();
+
+    @NotNull
+    default Map<Identifier, Data> getPlayerCustomDataStore(@NotNull OnlineUser user) {
+        if (getPlayerCustomDataStore().containsKey(user.getUuid())) {
+            return getPlayerCustomDataStore().get(user.getUuid());
+        }
+        final Map<Identifier, Data> data = new HashMap<>();
+        getPlayerCustomDataStore().put(user.getUuid(), data);
+        return data;
+    }
 
     /**
      * Initialize a faucet of the plugin.
@@ -193,14 +173,6 @@ public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider
      */
     InputStream getResource(@NotNull String name);
 
-    /**
-     * Returns the plugin data folder
-     *
-     * @return the plugin data folder as a {@link File}
-     */
-    @NotNull
-    File getDataFolder();
-
     /**
      * Log a message to the console
      *
@@ -293,10 +265,10 @@ public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider
     @NotNull
     default UpdateChecker getUpdateChecker() {
         return UpdateChecker.builder()
-                .currentVersion(getPluginVersion())
-                .endpoint(UpdateChecker.Endpoint.SPIGOT)
-                .resource(Integer.toString(SPIGOT_RESOURCE_ID))
-                .build();
+            .currentVersion(getPluginVersion())
+            .endpoint(UpdateChecker.Endpoint.SPIGOT)
+            .resource(Integer.toString(SPIGOT_RESOURCE_ID))
+            .build();
     }
 
     default void checkForUpdates() {
@@ -304,8 +276,8 @@ public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider
             getUpdateChecker().check().thenAccept(checked -> {
                 if (!checked.isUpToDate()) {
                     log(Level.WARNING, String.format(
-                            "A new version of HuskSync is available: v%s (running v%s)",
-                            checked.getLatestVersion(), getPluginVersion())
+                        "A new version of HuskSync is available: v%s (running v%s)",
+                        checked.getLatestVersion(), getPluginVersion())
                     );
                 }
             });
@@ -348,15 +320,15 @@ public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider
     final class FailedToLoadException extends IllegalStateException {
 
         private static final String FORMAT = """
-                HuskSync has failed to load! The plugin will not be enabled and no data will be synchronized.
-                Please make sure the plugin has been setup correctly (https://william278.net/docs/husksync/setup):
-                
-                1) Make sure you've entered your MySQL, MariaDB or MongoDB database details correctly in config.yml
-                2) Make sure your Redis server details are also correct in config.yml
-                3) Make sure your config is up-to-date (https://william278.net/docs/husksync/config-file)
-                4) Check the error below for more details
-                
-                Caused by: %s""";
+            HuskSync has failed to load! The plugin will not be enabled and no data will be synchronized.
+            Please make sure the plugin has been setup correctly (https://william278.net/docs/husksync/setup):
+                            
+            1) Make sure you've entered your MySQL, MariaDB or MongoDB database details correctly in config.yml
+            2) Make sure your Redis server details are also correct in config.yml
+            3) Make sure your config is up-to-date (https://william278.net/docs/husksync/config-file)
+            4) Check the error below for more details
+                            
+            Caused by: %s""";
 
         FailedToLoadException(@NotNull String message, @NotNull Throwable cause) {
             super(String.format(FORMAT, message), cause);

common/src/main/java/net/william278/husksync/adapter/GsonAdapter.java

@@ -49,7 +49,7 @@ public class GsonAdapter implements DataAdapter {
 
     @Override
     @NotNull
-    public <A extends Adaptable> A fromBytes(@NotNull byte[] data, @NotNull Class<A> type) throws AdaptionException {
+    public <A extends Adaptable> A fromBytes(byte[] data, @NotNull Class<A> type) throws AdaptionException {
         return this.fromJson(new String(data, StandardCharsets.UTF_8), type);
     }
 

common/src/main/java/net/william278/husksync/adapter/SnappyGsonAdapter.java

@@ -31,7 +31,6 @@ public class SnappyGsonAdapter extends GsonAdapter {
         super(plugin);
     }
 
-    @NotNull
     @Override
     public <A extends Adaptable> byte[] toBytes(@NotNull A data) throws AdaptionException {
         try {
@@ -43,7 +42,7 @@ public class SnappyGsonAdapter extends GsonAdapter {
 
     @NotNull
     @Override
-    public <A extends Adaptable> A fromBytes(@NotNull byte[] data, @NotNull Class<A> type) throws AdaptionException {
+    public <A extends Adaptable> A fromBytes(byte[] data, @NotNull Class<A> type) throws AdaptionException {
         try {
             return super.fromBytes(decompressBytes(data), type);
         } catch (IOException e) {

common/src/main/java/net/william278/husksync/api/HuskSyncAPI.java

@@ -378,6 +378,17 @@ public class HuskSyncAPI {
         plugin.registerSerializer(identifier, serializer);
     }
 
+    /**
+     * Get a registered data serializer by its identifier
+     *
+     * @param identifier The identifier of the data type to get the serializer for
+     * @return The serializer for the given identifier, or an empty optional if the serializer isn't registered
+     * @since 3.5.4
+     */
+    public Optional<Serializer<Data>> getDataSerializer(@NotNull Identifier identifier) {
+        return plugin.getSerializer(identifier);
+    }
+
     /**
      * Get a {@link DataSnapshot.Unpacked} from a {@link DataSnapshot.Packed}
      *
@@ -500,17 +511,19 @@ public class HuskSyncAPI {
      */
     static final class NotRegisteredException extends IllegalStateException {
 
-        private static final String MESSAGE = """
-                Could not access the HuskSync API as it has not yet been registered. This could be because:
+        private static final String REASONS = """
+                This may be because:
                 1) HuskSync has failed to enable successfully
                 2) Your plugin isn't set to load after HuskSync has
                    (Check if it set as a (soft)depend in plugin.yml or to load: BEFORE in paper-plugin.yml?)
-                3) You are attempting to access HuskSync on plugin construction/before your plugin has enabled.
-                4) You have shaded HuskSync into your plugin jar and need to fix your maven/gradle/build script
-                   to only include HuskSync as a dependency and not as a shaded dependency.""";
+                3) You are attempting to access HuskSync on plugin construction/before your plugin has enabled.""";
+
+        NotRegisteredException(@NotNull String reasons) {
+            super("Could not access the HuskSync API as it has not yet been registered. %s".formatted(reasons));
+        }
 
         NotRegisteredException() {
-            super(MESSAGE);
+            this(REASONS);
         }
 
     }

common/src/main/java/net/william278/husksync/command/Command.java

@@ -1,84 +0,0 @@
-/*
- * This file is part of HuskSync, licensed under the Apache License 2.0.
- *
- *  Copyright (c) William278 <will27528@gmail.com>
- *  Copyright (c) contributors
- *
- *  Licensed under the Apache License, Version 2.0 (the "License");
- *  you may not use this file except in compliance with the License.
- *  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- *  Unless required by applicable law or agreed to in writing, software
- *  distributed under the License is distributed on an "AS IS" BASIS,
- *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- *  See the License for the specific language governing permissions and
- *  limitations under the License.
- */
-
-package net.william278.husksync.command;
-
-import com.google.common.collect.Maps;
-import net.william278.husksync.HuskSync;
-import net.william278.husksync.user.CommandUser;
-import org.jetbrains.annotations.NotNull;
-
-import java.util.List;
-import java.util.Map;
-
-public abstract class Command extends Node {
-
-    private final String usage;
-    private final Map<String, Boolean> additionalPermissions;
-
-    protected Command(@NotNull String name, @NotNull List<String> aliases, @NotNull String usage,
-                      @NotNull HuskSync plugin) {
-        super(name, aliases, plugin);
-        this.usage = usage;
-        this.additionalPermissions = Maps.newHashMap();
-    }
-
-    @Override
-    public final void onExecuted(@NotNull CommandUser executor, @NotNull String[] args) {
-        if (!executor.hasPermission(getPermission())) {
-            plugin.getLocales().getLocale("error_no_permission")
-                    .ifPresent(executor::sendMessage);
-            return;
-        }
-        plugin.runAsync(() -> this.execute(executor, args));
-    }
-
-    public abstract void execute(@NotNull CommandUser executor, @NotNull String[] args);
-
-    @NotNull
-    public final String getRawUsage() {
-        return usage;
-    }
-
-    @NotNull
-    public final String getUsage() {
-        return "/" + getName() + " " + getRawUsage();
-    }
-
-    public final void addAdditionalPermissions(@NotNull Map<String, Boolean> permissions) {
-        permissions.forEach((permission, value) -> this.additionalPermissions.put(getPermission(permission), value));
-    }
-
-    @NotNull
-    public final Map<String, Boolean> getAdditionalPermissions() {
-        return additionalPermissions;
-    }
-
-    @NotNull
-    public String getDescription() {
-        return plugin.getLocales().getRawLocale(getName() + "_command_description")
-                .orElse(getUsage());
-    }
-
-    @NotNull
-    public final HuskSync getPlugin() {
-        return plugin;
-    }
-
-}

common/src/main/java/net/william278/husksync/command/EnderChestCommand.java

@@ -37,7 +37,7 @@ import java.util.Optional;
 public class EnderChestCommand extends ItemsCommand {
 
     public EnderChestCommand(@NotNull HuskSync plugin) {
-        super(plugin, List.of("enderchest", "echest", "openechest"));
+        super("enderchest", List.of("echest", "openechest"), plugin);
     }
 
     @Override
@@ -46,29 +46,29 @@ public class EnderChestCommand extends ItemsCommand {
         final Optional<Data.Items.EnderChest> optionalEnderChest = snapshot.getEnderChest();
         if (optionalEnderChest.isEmpty()) {
             plugin.getLocales().getLocale("error_no_data_to_display")
-                    .ifPresent(viewer::sendMessage);
+                .ifPresent(viewer::sendMessage);
             return;
         }
 
         // Display opening message
         plugin.getLocales().getLocale("ender_chest_viewer_opened", user.getUsername(),
-                        snapshot.getTimestamp().format(DateTimeFormatter
-                                .ofLocalizedDateTime(FormatStyle.MEDIUM, FormatStyle.SHORT)))
-                .ifPresent(viewer::sendMessage);
+                snapshot.getTimestamp().format(DateTimeFormatter
+                    .ofLocalizedDateTime(FormatStyle.MEDIUM, FormatStyle.SHORT)))
+            .ifPresent(viewer::sendMessage);
 
         // Show GUI
         final Data.Items.EnderChest enderChest = optionalEnderChest.get();
         viewer.showGui(
-                enderChest,
-                plugin.getLocales().getLocale("ender_chest_viewer_menu_title", user.getUsername())
-                        .orElse(new MineDown(String.format("%s's Ender Chest", user.getUsername()))),
-                allowEdit,
-                enderChest.getSlotCount(),
-                (itemsOnClose) -> {
-                    if (allowEdit && !enderChest.equals(itemsOnClose)) {
-                        plugin.runAsync(() -> this.updateItems(viewer, itemsOnClose, user));
-                    }
+            enderChest,
+            plugin.getLocales().getLocale("ender_chest_viewer_menu_title", user.getUsername())
+                .orElse(new MineDown(String.format("%s's Ender Chest", user.getUsername()))),
+            allowEdit,
+            enderChest.getSlotCount(),
+            (itemsOnClose) -> {
+                if (allowEdit && !enderChest.equals(itemsOnClose)) {
+                    plugin.runAsync(() -> this.updateItems(viewer, itemsOnClose, user));
                 }
+            }
         );
     }
 
@@ -78,7 +78,7 @@ public class EnderChestCommand extends ItemsCommand {
         final Optional<DataSnapshot.Packed> latestData = plugin.getDatabase().getLatestSnapshot(holder);
         if (latestData.isEmpty()) {
             plugin.getLocales().getLocale("error_no_data_to_display")
-                    .ifPresent(viewer::sendMessage);
+                .ifPresent(viewer::sendMessage);
             return;
         }
 
@@ -88,7 +88,7 @@ public class EnderChestCommand extends ItemsCommand {
             data.getEnderChest().ifPresent(enderChest -> enderChest.setContents(items));
             data.setSaveCause(DataSnapshot.SaveCause.ENDERCHEST_COMMAND);
             data.setPinned(
-                    plugin.getSettings().getSynchronization().doAutoPin(DataSnapshot.SaveCause.ENDERCHEST_COMMAND)
+                plugin.getSettings().getSynchronization().doAutoPin(DataSnapshot.SaveCause.ENDERCHEST_COMMAND)
             );
         });
 

common/src/main/java/net/william278/husksync/command/HuskSyncCommand.java

@@ -19,6 +19,8 @@
 
 package net.william278.husksync.command;
 
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
 import de.themoep.minedown.adventure.MineDown;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.JoinConfiguration;
@@ -31,221 +33,219 @@ import net.william278.husksync.HuskSync;
 import net.william278.husksync.database.Database;
 import net.william278.husksync.migrator.Migrator;
 import net.william278.husksync.user.CommandUser;
-import net.william278.husksync.user.OnlineUser;
+import net.william278.uniform.BaseCommand;
+import net.william278.uniform.CommandProvider;
+import net.william278.uniform.Permission;
+import net.william278.uniform.element.ArgumentElement;
 import org.apache.commons.text.WordUtils;
 import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
-import java.util.*;
+import java.util.Arrays;
+import java.util.List;
 import java.util.function.Function;
 import java.util.logging.Level;
 import java.util.stream.Collectors;
 
-public class HuskSyncCommand extends Command implements TabProvider {
-
-    private static final Map<String, Boolean> SUB_COMMANDS = Map.of(
-            "about", false,
-            "status", true,
-            "reload", true,
-            "migrate", true,
-            "update", true
-    );
+public class HuskSyncCommand extends PluginCommand {
 
     private final UpdateChecker updateChecker;
     private final AboutMenu aboutMenu;
 
     public HuskSyncCommand(@NotNull HuskSync plugin) {
-        super("husksync", List.of(), "[" + String.join("|", SUB_COMMANDS.keySet()) + "]", plugin);
-        addAdditionalPermissions(SUB_COMMANDS);
-
+        super("husksync", List.of(), Permission.Default.TRUE, plugin);
         this.updateChecker = plugin.getUpdateChecker();
         this.aboutMenu = AboutMenu.builder()
-                .title(Component.text("HuskSync"))
-                .description(Component.text("A modern, cross-server player data synchronization system"))
-                .version(plugin.getPluginVersion())
-                .credits("Author",
-                        AboutMenu.Credit.of("William278").description("Click to visit website").url("https://william278.net"))
-                .credits("Contributors",
-                        AboutMenu.Credit.of("HarvelsX").description("Code"),
-                        AboutMenu.Credit.of("HookWoods").description("Code"),
-                        AboutMenu.Credit.of("Preva1l").description("Code"))
-                .credits("Translators",
-                        AboutMenu.Credit.of("Namiu").description("Japanese (ja-jp)"),
-                        AboutMenu.Credit.of("anchelthe").description("Spanish (es-es)"),
-                        AboutMenu.Credit.of("Melonzio").description("Spanish (es-es)"),
-                        AboutMenu.Credit.of("Ceddix").description("German (de-de)"),
-                        AboutMenu.Credit.of("Pukejoy_1").description("Bulgarian (bg-bg)"),
-                        AboutMenu.Credit.of("mateusneresrb").description("Brazilian Portuguese (pt-br)"),
-                        AboutMenu.Credit.of("小蔡").description("Traditional Chinese (zh-tw)"),
-                        AboutMenu.Credit.of("Ghost-chu").description("Simplified Chinese (zh-cn)"),
-                        AboutMenu.Credit.of("DJelly4K").description("Simplified Chinese (zh-cn)"),
-                        AboutMenu.Credit.of("Thourgard").description("Ukrainian (uk-ua)"),
-                        AboutMenu.Credit.of("xF3d3").description("Italian (it-it)"),
-                        AboutMenu.Credit.of("cada3141").description("Korean (ko-kr)"),
-                        AboutMenu.Credit.of("Wirayuda5620").description("Indonesian (id-id)"),
-                        AboutMenu.Credit.of("WinTone01").description("Turkish (tr-tr)"),
-                        AboutMenu.Credit.of("IbanEtchep").description("French (fr-fr)"))
-                .buttons(
-                        AboutMenu.Link.of("https://william278.net/docs/husksync").text("Documentation").icon("⛏"),
-                        AboutMenu.Link.of("https://github.com/WiIIiam278/HuskSync/issues").text("Issues").icon("❌").color(TextColor.color(0xff9f0f)),
-                        AboutMenu.Link.of("https://discord.gg/tVYhJfyDWG").text("Discord").icon("⭐").color(TextColor.color(0x6773f5)))
-                .build();
+            .title(Component.text("HuskSync"))
+            .description(Component.text("A modern, cross-server player data synchronization system"))
+            .version(plugin.getPluginVersion())
+            .credits("Author",
+                AboutMenu.Credit.of("William278").description("Click to visit website").url("https://william278.net"))
+            .credits("Contributors",
+                AboutMenu.Credit.of("HarvelsX").description("Code"),
+                AboutMenu.Credit.of("HookWoods").description("Code"),
+                AboutMenu.Credit.of("Preva1l").description("Code"),
+                AboutMenu.Credit.of("hanbings").description("Code (Fabric porting)"),
+                AboutMenu.Credit.of("Stampede2011").description("Code (Fabric mixins)"))
+            .credits("Translators",
+                AboutMenu.Credit.of("Namiu").description("Japanese (ja-jp)"),
+                AboutMenu.Credit.of("anchelthe").description("Spanish (es-es)"),
+                AboutMenu.Credit.of("Melonzio").description("Spanish (es-es)"),
+                AboutMenu.Credit.of("Ceddix").description("German (de-de)"),
+                AboutMenu.Credit.of("Pukejoy_1").description("Bulgarian (bg-bg)"),
+                AboutMenu.Credit.of("mateusneresrb").description("Brazilian Portuguese (pt-br)"),
+                AboutMenu.Credit.of("小蔡").description("Traditional Chinese (zh-tw)"),
+                AboutMenu.Credit.of("Ghost-chu").description("Simplified Chinese (zh-cn)"),
+                AboutMenu.Credit.of("DJelly4K").description("Simplified Chinese (zh-cn)"),
+                AboutMenu.Credit.of("Thourgard").description("Ukrainian (uk-ua)"),
+                AboutMenu.Credit.of("xF3d3").description("Italian (it-it)"),
+                AboutMenu.Credit.of("cada3141").description("Korean (ko-kr)"),
+                AboutMenu.Credit.of("Wirayuda5620").description("Indonesian (id-id)"),
+                AboutMenu.Credit.of("WinTone01").description("Turkish (tr-tr)"),
+                AboutMenu.Credit.of("IbanEtchep").description("French (fr-fr)"))
+            .buttons(
+                AboutMenu.Link.of("https://william278.net/docs/husksync").text("Documentation").icon("⛏"),
+                AboutMenu.Link.of("https://github.com/WiIIiam278/HuskSync/issues").text("Issues").icon("❌").color(TextColor.color(0xff9f0f)),
+                AboutMenu.Link.of("https://discord.gg/tVYhJfyDWG").text("Discord").icon("⭐").color(TextColor.color(0x6773f5)))
+            .build();
     }
 
     @Override
-    public void execute(@NotNull CommandUser executor, @NotNull String[] args) {
-        final String subCommand = parseStringArg(args, 0).orElse("about").toLowerCase(Locale.ENGLISH);
-        if (SUB_COMMANDS.containsKey(subCommand) && !executor.hasPermission(getPermission(subCommand))) {
-            plugin.getLocales().getLocale("error_no_permission")
-                    .ifPresent(executor::sendMessage);
-            return;
-        }
-
-        switch (subCommand) {
-            case "about" -> executor.sendMessage(aboutMenu.toComponent());
-            case "status" -> {
-                getPlugin().getLocales().getLocale("system_status_header").ifPresent(executor::sendMessage);
-                executor.sendMessage(Component.join(
-                        JoinConfiguration.newlines(),
-                        Arrays.stream(StatusLine.values()).map(s -> s.get(plugin)).toList()
-                ));
-            }
-            case "reload" -> {
-                try {
-                    plugin.loadSettings();
-                    plugin.loadLocales();
-                    plugin.loadServer();
-                    plugin.getLocales().getLocale("reload_complete").ifPresent(executor::sendMessage);
-                } catch (Throwable e) {
-                    executor.sendMessage(new MineDown(
-                            "[Error:](#ff3300) [Failed to reload the plugin. Check console for errors.](#ff7e5e)"
-                    ));
-                    plugin.log(Level.SEVERE, "Failed to reload the plugin", e);
-                }
-            }
-            case "migrate" -> {
-                if (executor instanceof OnlineUser) {
-                    plugin.getLocales().getLocale("error_console_command_only")
-                            .ifPresent(executor::sendMessage);
-                    return;
-                }
-                this.handleMigrationCommand(args);
-            }
-            case "update" -> updateChecker.check().thenAccept(checked -> {
-                if (checked.isUpToDate()) {
-                    plugin.getLocales().getLocale("up_to_date", plugin.getPluginVersion().toString())
-                            .ifPresent(executor::sendMessage);
-                    return;
-                }
-                plugin.getLocales().getLocale("update_available", checked.getLatestVersion().toString(),
-                        plugin.getPluginVersion().toString()).ifPresent(executor::sendMessage);
-            });
-            default -> plugin.getLocales().getLocale("error_invalid_syntax", getUsage())
-                    .ifPresent(executor::sendMessage);
-        }
+    public void provide(@NotNull BaseCommand<?> command) {
+        command.setDefaultExecutor((ctx) -> about(command, ctx));
+        command.addSubCommand("about", (sub) -> sub.setDefaultExecutor((ctx) -> about(command, ctx)));
+        command.addSubCommand("status", needsOp("status"), status());
+        command.addSubCommand("reload", needsOp("reload"), reload());
+        command.addSubCommand("update", needsOp("update"), update());
+        command.addSubCommand("migrate", migrate());
     }
 
-    // Handle a migration console command input
-    private void handleMigrationCommand(@NotNull String[] args) {
-        if (args.length < 2) {
-            plugin.log(Level.INFO,
-                    "Please choose a migrator, then run \"husksync migrate <migrator>\"");
-            this.logMigratorList();
-            return;
-        }
+    private void about(@NotNull BaseCommand<?> c, @NotNull CommandContext<?> ctx) {
+        user(c, ctx).getAudience().sendMessage(aboutMenu.toComponent());
+    }
 
-        final Optional<Migrator> selectedMigrator = plugin.getAvailableMigrators().stream()
-                .filter(available -> available.getIdentifier().equalsIgnoreCase(args[1]))
-                .findFirst();
-        selectedMigrator.ifPresentOrElse(migrator -> {
-            if (args.length < 3) {
-                plugin.log(Level.INFO, migrator.getHelpMenu());
+    @NotNull
+    private CommandProvider status() {
+        return (sub) -> sub.setDefaultExecutor((ctx) -> {
+            final CommandUser user = user(sub, ctx);
+            plugin.getLocales().getLocale("system_status_header").ifPresent(user::sendMessage);
+            user.sendMessage(Component.join(
+                JoinConfiguration.newlines(),
+                Arrays.stream(StatusLine.values()).map(s -> s.get(plugin)).toList()
+            ));
+        });
+    }
+
+    @NotNull
+    private CommandProvider reload() {
+        return (sub) -> sub.setDefaultExecutor((ctx) -> {
+            final CommandUser user = user(sub, ctx);
+            try {
+                plugin.loadSettings();
+                plugin.loadLocales();
+                plugin.loadServer();
+                plugin.getLocales().getLocale("reload_complete").ifPresent(user::sendMessage);
+            } catch (Throwable e) {
+                user.sendMessage(new MineDown(
+                    "[Error:](#ff3300) [Failed to reload the plugin. Check console for errors.](#ff7e5e)"
+                ));
+                plugin.log(Level.SEVERE, "Failed to reload the plugin", e);
+            }
+        });
+    }
+
+    @NotNull
+    private CommandProvider update() {
+        return (sub) -> sub.setDefaultExecutor((ctx) -> updateChecker.check().thenAccept(checked -> {
+            final CommandUser user = user(sub, ctx);
+            if (checked.isUpToDate()) {
+                plugin.getLocales().getLocale("up_to_date", plugin.getPluginVersion().toString())
+                    .ifPresent(user::sendMessage);
                 return;
             }
-            switch (args[2]) {
-                case "start" -> migrator.start().thenAccept(succeeded -> {
+            plugin.getLocales().getLocale("update_available", checked.getLatestVersion().toString(),
+                plugin.getPluginVersion().toString()).ifPresent(user::sendMessage);
+        }));
+    }
+
+    @NotNull
+    private CommandProvider migrate() {
+        return (sub) -> {
+            sub.setCondition((ctx) -> sub.getUser(ctx).isConsole());
+            sub.setDefaultExecutor((ctx) -> {
+                plugin.log(Level.INFO, "Please choose a migrator, then run \"husksync migrate <migrator>\"");
+                plugin.log(Level.INFO, String.format(
+                    "List of available migrators:\nMigrator ID / Migrator Name:\n%s",
+                    plugin.getAvailableMigrators().stream()
+                        .map(migrator -> String.format("%s - %s", migrator.getIdentifier(), migrator.getName()))
+                        .collect(Collectors.joining("\n"))
+                ));
+            });
+            sub.addSubCommand("start", (start) -> start.addSyntax((cmd) -> {
+                final Migrator migrator = cmd.getArgument("migrator", Migrator.class);
+                migrator.start().thenAccept(succeeded -> {
                     if (succeeded) {
                         plugin.log(Level.INFO, "Migration completed successfully!");
                     } else {
                         plugin.log(Level.WARNING, "Migration failed!");
                     }
                 });
-                case "set" -> migrator.handleConfigurationCommand(Arrays.copyOfRange(args, 3, args.length));
-                default -> plugin.log(Level.INFO, String.format(
-                        "Invalid syntax. Console usage: \"husksync migrate %s <start/set>", args[1]
-                ));
-            }
-        }, () -> {
-            plugin.log(Level.INFO,
-                    "Please specify a valid migrator.\n" +
-                            "If a migrator is not available, please verify that you meet the prerequisites to use it.");
-            this.logMigratorList();
-        });
-    }
-
-    // Log the list of available migrators
-    private void logMigratorList() {
-        plugin.log(Level.INFO, String.format(
-                "List of available migrators:\nMigrator ID / Migrator Name:\n%s",
-                plugin.getAvailableMigrators().stream()
-                        .map(migrator -> String.format("%s - %s", migrator.getIdentifier(), migrator.getName()))
-                        .collect(Collectors.joining("\n"))
-        ));
-    }
-
-    @Nullable
-    @Override
-    public List<String> suggest(@NotNull CommandUser user, @NotNull String[] args) {
-        return switch (args.length) {
-            case 0, 1 -> SUB_COMMANDS.keySet().stream().sorted().toList();
-            default -> null;
+            }, migrator()));
+            sub.addSubCommand("set", (set) -> set.addSyntax((cmd) -> {
+                final Migrator migrator = cmd.getArgument("migrator", Migrator.class);
+                final String[] args = cmd.getArgument("args", String.class).split(" ");
+                migrator.handleConfigurationCommand(Arrays.copyOfRange(args, 3, args.length));
+            }, migrator(), BaseCommand.greedyString("args")));
         };
     }
 
+    @NotNull
+    private <S> ArgumentElement<S, Migrator> migrator() {
+        return new ArgumentElement<>("migrator", reader -> {
+            final String id = reader.readString();
+            final Migrator migrator = plugin.getAvailableMigrators().stream()
+                .filter(m -> m.getIdentifier().equalsIgnoreCase(id)).findFirst().orElse(null);
+            if (migrator == null) {
+                throw CommandSyntaxException.BUILT_IN_EXCEPTIONS.dispatcherUnknownArgument().createWithContext(reader);
+            }
+            return migrator;
+        }, (context, builder) -> {
+            for (Migrator material : plugin.getAvailableMigrators()) {
+                builder.suggest(material.getIdentifier());
+            }
+            return builder.buildFuture();
+        });
+    }
+
     private enum StatusLine {
         PLUGIN_VERSION(plugin -> Component.text("v" + plugin.getPluginVersion().toStringWithoutMetadata())
-                .appendSpace().append(plugin.getPluginVersion().getMetadata().isBlank() ? Component.empty()
-                        : Component.text("(build " + plugin.getPluginVersion().getMetadata() + ")"))),
+            .appendSpace().append(plugin.getPluginVersion().getMetadata().isBlank() ? Component.empty()
+                : Component.text("(build " + plugin.getPluginVersion().getMetadata() + ")"))),
         PLATFORM_TYPE(plugin -> Component.text(WordUtils.capitalizeFully(plugin.getPlatformType()))),
         LANGUAGE(plugin -> Component.text(plugin.getSettings().getLanguage())),
         MINECRAFT_VERSION(plugin -> Component.text(plugin.getMinecraftVersion().toString())),
         JAVA_VERSION(plugin -> Component.text(System.getProperty("java.version"))),
         JAVA_VENDOR(plugin -> Component.text(System.getProperty("java.vendor"))),
         SYNC_MODE(plugin -> Component.text(WordUtils.capitalizeFully(
-                plugin.getSettings().getSynchronization().getMode().toString()
+            plugin.getSettings().getSynchronization().getMode().toString()
         ))),
         DELAY_LATENCY(plugin -> Component.text(
-                plugin.getSettings().getSynchronization().getNetworkLatencyMilliseconds() + "ms"
+            plugin.getSettings().getSynchronization().getNetworkLatencyMilliseconds() + "ms"
         )),
         SERVER_NAME(plugin -> Component.text(plugin.getServerName())),
         CLUSTER_ID(plugin -> Component.text(plugin.getSettings().getClusterId().isBlank() ? "None" : plugin.getSettings().getClusterId())),
         DATABASE_TYPE(plugin ->
-                Component.text(plugin.getSettings().getDatabase().getType().getDisplayName() +
-                        (plugin.getSettings().getDatabase().getType() == Database.Type.MONGO ?
-                                (plugin.getSettings().getDatabase().getMongoSettings().isUsingAtlas() ? " Atlas" : "") : ""))
+            Component.text(plugin.getSettings().getDatabase().getType().getDisplayName() +
+                (plugin.getSettings().getDatabase().getType() == Database.Type.MONGO ?
+                    (plugin.getSettings().getDatabase().getMongoSettings().isUsingAtlas() ? " Atlas" : "") : ""))
         ),
         IS_DATABASE_LOCAL(plugin -> getLocalhostBoolean(plugin.getSettings().getDatabase().getCredentials().getHost())),
         USING_REDIS_SENTINEL(plugin -> getBoolean(
-                !plugin.getSettings().getRedis().getSentinel().getMaster().isBlank()
+            !plugin.getSettings().getRedis().getSentinel().getMaster().isBlank()
         )),
         USING_REDIS_PASSWORD(plugin -> getBoolean(
-                !plugin.getSettings().getRedis().getCredentials().getPassword().isBlank()
+            !plugin.getSettings().getRedis().getCredentials().getPassword().isBlank()
         )),
         REDIS_USING_SSL(plugin -> getBoolean(
-                plugin.getSettings().getRedis().getCredentials().isUseSsl()
+            plugin.getSettings().getRedis().getCredentials().isUseSsl()
         )),
         IS_REDIS_LOCAL(plugin -> getLocalhostBoolean(
-                plugin.getSettings().getRedis().getCredentials().getHost()
+            plugin.getSettings().getRedis().getCredentials().getHost()
         )),
         DATA_TYPES(plugin -> Component.join(
-                JoinConfiguration.commas(true),
-                plugin.getRegisteredDataTypes().stream().map(i -> {
-                    boolean enabled = plugin.getSettings().getSynchronization().isFeatureEnabled(i);
-                    return Component.textOfChildren(Component
-                                    .text(i.toString()).appendSpace().append(Component.text(enabled ? '✔' : '❌')))
-                            .color(enabled ? NamedTextColor.GREEN : NamedTextColor.RED)
-                            .hoverEvent(HoverEvent.showText(Component.text(enabled ? "Enabled" : "Disabled")));
-                }).toList()
+            JoinConfiguration.commas(true),
+            plugin.getRegisteredDataTypes().stream().map(i -> Component.textOfChildren(Component.text(i.toString())
+                    .appendSpace().append(Component.text(i.isEnabled() ? '✔' : '❌')))
+                .color(i.isEnabled() ? NamedTextColor.GREEN : NamedTextColor.RED)
+                .hoverEvent(HoverEvent.showText(
+                    Component.text(i.isEnabled() ? "Enabled" : "Disabled")
+                        .append(Component.newline())
+                        .append(Component.text("Dependencies: %s".formatted(i.getDependencies()
+                            .isEmpty() ? "(None)" : i.getDependencies().stream()
+                            .map(d -> "%s (%s)".formatted(
+                                d.getKey().value(), d.isRequired() ? "Required" : "Optional"
+                            )).collect(Collectors.joining(", ")))
+                        ).color(NamedTextColor.GRAY))
+                ))).toList()
         ));
 
         private final Function<HuskSync, Component> supplier;
@@ -257,13 +257,13 @@ public class HuskSyncCommand extends Command implements TabProvider {
         @NotNull
         private Component get(@NotNull HuskSync plugin) {
             return Component
-                    .text("•").appendSpace()
-                    .append(Component.text(
-                            WordUtils.capitalizeFully(name().replaceAll("_", " ")),
-                            TextColor.color(0x848484)
-                    ))
-                    .append(Component.text(':')).append(Component.space().color(NamedTextColor.WHITE))
-                    .append(supplier.apply(plugin));
+                .text("•").appendSpace()
+                .append(Component.text(
+                    WordUtils.capitalizeFully(name().replaceAll("_", " ")),
+                    TextColor.color(0x848484)
+                ))
+                .append(Component.text(':')).append(Component.space().color(NamedTextColor.WHITE))
+                .append(supplier.apply(plugin));
         }
 
         @NotNull
@@ -274,7 +274,7 @@ public class HuskSyncCommand extends Command implements TabProvider {
         @NotNull
         private static Component getLocalhostBoolean(@NotNull String value) {
             return getBoolean(value.equals("127.0.0.1") || value.equals("0.0.0.0")
-                    || value.equals("localhost") || value.equals("::1"));
+                || value.equals("localhost") || value.equals("::1"));
         }
     }
 

common/src/main/java/net/william278/husksync/command/InventoryCommand.java

@@ -37,7 +37,7 @@ import java.util.Optional;
 public class InventoryCommand extends ItemsCommand {
 
     public InventoryCommand(@NotNull HuskSync plugin) {
-        super(plugin, List.of("inventory", "invsee", "openinv"));
+        super("inventory", List.of("invsee", "openinv"), plugin);
     }
 
     @Override
@@ -45,30 +45,31 @@ public class InventoryCommand extends ItemsCommand {
                              @NotNull User user, boolean allowEdit) {
         final Optional<Data.Items.Inventory> optionalInventory = snapshot.getInventory();
         if (optionalInventory.isEmpty()) {
+            viewer.sendMessage(new MineDown("what the FUCK is happening"));
             plugin.getLocales().getLocale("error_no_data_to_display")
-                    .ifPresent(viewer::sendMessage);
+                .ifPresent(viewer::sendMessage);
             return;
         }
 
         // Display opening message
         plugin.getLocales().getLocale("inventory_viewer_opened", user.getUsername(),
-                        snapshot.getTimestamp().format(DateTimeFormatter
-                                .ofLocalizedDateTime(FormatStyle.MEDIUM, FormatStyle.SHORT)))
-                .ifPresent(viewer::sendMessage);
+                snapshot.getTimestamp().format(DateTimeFormatter
+                    .ofLocalizedDateTime(FormatStyle.MEDIUM, FormatStyle.SHORT)))
+            .ifPresent(viewer::sendMessage);
 
         // Show GUI
         final Data.Items.Inventory inventory = optionalInventory.get();
         viewer.showGui(
-                inventory,
-                plugin.getLocales().getLocale("inventory_viewer_menu_title", user.getUsername())
-                        .orElse(new MineDown(String.format("%s's Inventory", user.getUsername()))),
-                allowEdit,
-                inventory.getSlotCount(),
-                (itemsOnClose) -> {
-                    if (allowEdit && !inventory.equals(itemsOnClose)) {
-                        plugin.runAsync(() -> this.updateItems(viewer, itemsOnClose, user));
-                    }
+            inventory,
+            plugin.getLocales().getLocale("inventory_viewer_menu_title", user.getUsername())
+                .orElse(new MineDown(String.format("%s's Inventory", user.getUsername()))),
+            allowEdit,
+            inventory.getSlotCount(),
+            (itemsOnClose) -> {
+                if (allowEdit && !inventory.equals(itemsOnClose)) {
+                    plugin.runAsync(() -> this.updateItems(viewer, itemsOnClose, user));
                 }
+            }
         );
     }
 
@@ -78,7 +79,7 @@ public class InventoryCommand extends ItemsCommand {
         final Optional<DataSnapshot.Packed> latestData = plugin.getDatabase().getLatestSnapshot(holder);
         if (latestData.isEmpty()) {
             plugin.getLocales().getLocale("error_no_data_to_display")
-                    .ifPresent(viewer::sendMessage);
+                .ifPresent(viewer::sendMessage);
             return;
         }
 
@@ -88,7 +89,7 @@ public class InventoryCommand extends ItemsCommand {
             data.getInventory().ifPresent(inventory -> inventory.setContents(items));
             data.setSaveCause(DataSnapshot.SaveCause.INVENTORY_COMMAND);
             data.setPinned(
-                    plugin.getSettings().getSynchronization().doAutoPin(DataSnapshot.SaveCause.INVENTORY_COMMAND)
+                plugin.getSettings().getSynchronization().doAutoPin(DataSnapshot.SaveCause.INVENTORY_COMMAND)
             );
         });
 

common/src/main/java/net/william278/husksync/command/ItemsCommand.java

@@ -24,102 +24,90 @@ import net.william278.husksync.data.DataSnapshot;
 import net.william278.husksync.user.CommandUser;
 import net.william278.husksync.user.OnlineUser;
 import net.william278.husksync.user.User;
+import net.william278.uniform.BaseCommand;
+import net.william278.uniform.Permission;
 import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
 import java.util.List;
-import java.util.Map;
 import java.util.Optional;
 import java.util.UUID;
 
-public abstract class ItemsCommand extends Command implements TabProvider {
+public abstract class ItemsCommand extends PluginCommand {
 
-    protected ItemsCommand(@NotNull HuskSync plugin, @NotNull List<String> aliases) {
-        super(aliases.get(0), aliases.subList(1, aliases.size()), "<player> [version_uuid]", plugin);
-        setOperatorCommand(true);
-        addAdditionalPermissions(Map.of("edit", true));
+    protected ItemsCommand(@NotNull String name, @NotNull List<String> aliases, @NotNull HuskSync plugin) {
+        super(name, aliases, Permission.Default.IF_OP, plugin);
     }
 
-
     @Override
-    public void execute(@NotNull CommandUser executor, @NotNull String[] args) {
-        if (!(executor instanceof OnlineUser player)) {
-            plugin.getLocales().getLocale("error_in_game_command_only")
+    public void provide(@NotNull BaseCommand<?> command) {
+        command.addSyntax((ctx) -> {
+            final User user = ctx.getArgument("username", User.class);
+            final UUID version = ctx.getArgument("version", UUID.class);
+            final CommandUser executor = user(command, ctx);
+            if (!(executor instanceof OnlineUser online)) {
+                plugin.getLocales().getLocale("error_in_game_command_only")
                     .ifPresent(executor::sendMessage);
-            return;
-        }
-
-        // Find the user to view the items for
-        final Optional<User> optionalUser = parseStringArg(args, 0)
-                .flatMap(name -> plugin.getDatabase().getUserByName(name));
-        if (optionalUser.isEmpty()) {
-            plugin.getLocales().getLocale(
-                    args.length >= 1 ? "error_invalid_player" : "error_invalid_syntax", getUsage()
-            ).ifPresent(player::sendMessage);
-            return;
-        }
-
-        // Show the user data
-        final User user = optionalUser.get();
-        parseUUIDArg(args, 1).ifPresentOrElse(
-                version -> this.showSnapshotItems(player, user, version),
-                () -> this.showLatestItems(player, user)
-        );
+                return;
+            }
+            this.showSnapshotItems(online, user, version);
+        }, user("username"), uuid("version"));
+        command.addSyntax((ctx) -> {
+            final User user = ctx.getArgument("username", User.class);
+            final CommandUser executor = user(command, ctx);
+            if (!(executor instanceof OnlineUser online)) {
+                plugin.getLocales().getLocale("error_in_game_command_only")
+                    .ifPresent(executor::sendMessage);
+                return;
+            }
+            this.showLatestItems(online, user);
+        }, user("username"));
     }
 
     // View (and edit) the latest user data
     private void showLatestItems(@NotNull OnlineUser viewer, @NotNull User user) {
         plugin.getRedisManager().getUserData(user.getUuid(), user).thenAccept(data -> data
-                .or(() -> plugin.getDatabase().getLatestSnapshot(user))
-                .or(() -> {
-                    plugin.getLocales().getLocale("error_no_data_to_display")
-                            .ifPresent(viewer::sendMessage);
+            .or(() -> plugin.getDatabase().getLatestSnapshot(user))
+            .or(() -> {
+                plugin.getLocales().getLocale("error_no_data_to_display")
+                    .ifPresent(viewer::sendMessage);
+                return Optional.empty();
+            })
+            .flatMap(packed -> {
+                if (packed.isInvalid()) {
+                    plugin.getLocales().getLocale("error_invalid_data", packed.getInvalidReason(plugin))
+                        .ifPresent(viewer::sendMessage);
                     return Optional.empty();
-                })
-                .flatMap(packed -> {
-                    if (packed.isInvalid()) {
-                        plugin.getLocales().getLocale("error_invalid_data", packed.getInvalidReason(plugin))
-                                .ifPresent(viewer::sendMessage);
-                        return Optional.empty();
-                    }
-                    return Optional.of(packed.unpack(plugin));
-                })
-                .ifPresent(snapshot -> this.showItems(
-                        viewer, snapshot, user, viewer.hasPermission(getPermission("edit"))
-                )));
+                }
+                return Optional.of(packed.unpack(plugin));
+            })
+            .ifPresent(snapshot -> this.showItems(
+                viewer, snapshot, user, viewer.hasPermission(getPermission("edit"))
+            )));
     }
 
     // View a specific version of the user data
     private void showSnapshotItems(@NotNull OnlineUser viewer, @NotNull User user, @NotNull UUID version) {
         plugin.getDatabase().getSnapshot(user, version)
-                .or(() -> {
-                    plugin.getLocales().getLocale("error_invalid_version_uuid")
-                            .ifPresent(viewer::sendMessage);
+            .or(() -> {
+                plugin.getLocales().getLocale("error_invalid_version_uuid")
+                    .ifPresent(viewer::sendMessage);
+                return Optional.empty();
+            })
+            .flatMap(packed -> {
+                if (packed.isInvalid()) {
+                    plugin.getLocales().getLocale("error_invalid_data", packed.getInvalidReason(plugin))
+                        .ifPresent(viewer::sendMessage);
                     return Optional.empty();
-                })
-                .flatMap(packed -> {
-                    if (packed.isInvalid()) {
-                        plugin.getLocales().getLocale("error_invalid_data", packed.getInvalidReason(plugin))
-                                .ifPresent(viewer::sendMessage);
-                        return Optional.empty();
-                    }
-                    return Optional.of(packed.unpack(plugin));
-                })
-                .ifPresent(snapshot -> this.showItems(
-                        viewer, snapshot, user, false
-                ));
+                }
+                return Optional.of(packed.unpack(plugin));
+            })
+            .ifPresent(snapshot -> this.showItems(
+                viewer, snapshot, user, false
+            ));
     }
 
     // Show a GUI menu with the correct item data from the snapshot
     protected abstract void showItems(@NotNull OnlineUser viewer, @NotNull DataSnapshot.Unpacked snapshot,
                                       @NotNull User user, boolean allowEdit);
 
-    @Nullable
-    @Override
-    public List<String> suggest(@NotNull CommandUser executor, @NotNull String[] args) {
-        return switch (args.length) {
-            case 0, 1 -> plugin.getOnlineUsers().stream().map(User::getUsername).toList();
-            default -> null;
-        };
-    }
 }

common/src/main/java/net/william278/husksync/command/Node.java

@@ -1,105 +0,0 @@
-/*
- * This file is part of HuskSync, licensed under the Apache License 2.0.
- *
- *  Copyright (c) William278 <will27528@gmail.com>
- *  Copyright (c) contributors
- *
- *  Licensed under the Apache License, Version 2.0 (the "License");
- *  you may not use this file except in compliance with the License.
- *  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- *  Unless required by applicable law or agreed to in writing, software
- *  distributed under the License is distributed on an "AS IS" BASIS,
- *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- *  See the License for the specific language governing permissions and
- *  limitations under the License.
- */
-
-package net.william278.husksync.command;
-
-import net.william278.husksync.HuskSync;
-import org.jetbrains.annotations.NotNull;
-
-import java.util.List;
-import java.util.Optional;
-import java.util.StringJoiner;
-import java.util.UUID;
-
-public abstract class Node implements Executable {
-
-    protected static final String PERMISSION_PREFIX = "husksync.command";
-
-    protected final HuskSync plugin;
-    private final String name;
-    private final List<String> aliases;
-    private boolean operatorCommand = false;
-
-    protected Node(@NotNull String name, @NotNull List<String> aliases, @NotNull HuskSync plugin) {
-        if (name.isBlank()) {
-            throw new IllegalArgumentException("Command name cannot be blank");
-        }
-        this.name = name;
-        this.aliases = aliases;
-        this.plugin = plugin;
-    }
-
-    @NotNull
-    public String getName() {
-        return name;
-    }
-
-    @NotNull
-    public List<String> getAliases() {
-        return aliases;
-    }
-
-    @NotNull
-    public String getPermission(@NotNull String... child) {
-        final StringJoiner joiner = new StringJoiner(".")
-                .add(PERMISSION_PREFIX)
-                .add(getName());
-        for (final String node : child) {
-            joiner.add(node);
-        }
-        return joiner.toString().trim();
-    }
-
-    public boolean isOperatorCommand() {
-        return operatorCommand;
-    }
-
-    public void setOperatorCommand(boolean operatorCommand) {
-        this.operatorCommand = operatorCommand;
-    }
-
-    protected Optional<String> parseStringArg(@NotNull String[] args, int index) {
-        if (args.length > index) {
-            return Optional.of(args[index]);
-        }
-        return Optional.empty();
-    }
-
-    protected Optional<Integer> parseIntArg(@NotNull String[] args, int index) {
-        return parseStringArg(args, index).flatMap(arg -> {
-            try {
-                return Optional.of(Integer.parseInt(arg));
-            } catch (NumberFormatException e) {
-                return Optional.empty();
-            }
-        });
-    }
-
-    protected Optional<UUID> parseUUIDArg(@NotNull String[] args, int index) {
-        return parseStringArg(args, index).flatMap(arg -> {
-            try {
-                return Optional.of(UUID.fromString(arg));
-            } catch (IllegalArgumentException e) {
-                return Optional.empty();
-            }
-        });
-    }
-
-
-}

common/src/main/java/net/william278/husksync/command/PluginCommand.java

@@ -0,0 +1,129 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.command;
+
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import net.william278.husksync.HuskSync;
+import net.william278.husksync.user.CommandUser;
+import net.william278.husksync.user.User;
+import net.william278.uniform.BaseCommand;
+import net.william278.uniform.Command;
+import net.william278.uniform.Permission;
+import net.william278.uniform.element.ArgumentElement;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.UUID;
+import java.util.function.Function;
+
+public abstract class PluginCommand extends Command {
+
+    protected final HuskSync plugin;
+
+    protected PluginCommand(@NotNull String name, @NotNull List<String> aliases,
+                            @NotNull Permission.Default permissionDefault, @NotNull HuskSync plugin) {
+        super(name, aliases, getDescription(plugin, name), new Permission(createPermission(name), permissionDefault));
+        this.plugin = plugin;
+    }
+
+    private static String getDescription(@NotNull HuskSync plugin, @NotNull String name) {
+        return plugin.getLocales().getRawLocale("%s_command_description".formatted(name)).orElse("");
+    }
+
+    @NotNull
+    private static String createPermission(@NotNull String name, @NotNull String... sub) {
+        return "husksync.command." + name + (sub.length > 0 ? "." + String.join(".", sub) : "");
+    }
+
+    @NotNull
+    protected String getPermission(@NotNull String... sub) {
+        return createPermission(this.getName(), sub);
+    }
+
+    @NotNull
+    @SuppressWarnings("rawtypes")
+    protected CommandUser user(@NotNull BaseCommand base, @NotNull CommandContext context) {
+        return adapt(base.getUser(context.getSource()));
+    }
+
+    @NotNull
+    protected Permission needsOp(@NotNull String... nodes) {
+        return new Permission(getPermission(nodes), Permission.Default.IF_OP);
+    }
+
+    @NotNull
+    protected CommandUser adapt(net.william278.uniform.CommandUser user) {
+        return user.getUuid() == null ? plugin.getConsole() : plugin.getOnlineUser(user.getUuid()).orElseThrow();
+    }
+
+    @NotNull
+    protected <S> ArgumentElement<S, User> user(@NotNull String name) {
+        return new ArgumentElement<>(name, reader -> {
+            final String username = reader.readString();
+            return plugin.getDatabase().getUserByName(username).orElseThrow(
+                    () -> CommandSyntaxException.BUILT_IN_EXCEPTIONS.dispatcherUnknownArgument().createWithContext(reader)
+            );
+        }, (context, builder) -> {
+            plugin.getOnlineUsers().forEach(u -> builder.suggest(u.getUsername()));
+            return builder.buildFuture();
+        });
+    }
+
+    @NotNull
+    protected <S> ArgumentElement<S, UUID> uuid(@NotNull String name) {
+        return new ArgumentElement<>(name, reader -> {
+            try {
+                return UUID.fromString(reader.readString());
+            } catch (IllegalArgumentException e) {
+                throw CommandSyntaxException.BUILT_IN_EXCEPTIONS.dispatcherUnknownArgument().createWithContext(reader);
+            }
+        }, (context, builder) -> builder.buildFuture());
+    }
+
+    public enum Type {
+
+        HUSKSYNC_COMMAND(HuskSyncCommand::new),
+        USERDATA_COMMAND(UserDataCommand::new),
+        INVENTORY_COMMAND(InventoryCommand::new),
+        ENDER_CHEST_COMMAND(EnderChestCommand::new);
+
+        public final Function<HuskSync, PluginCommand> commandSupplier;
+
+        Type(@NotNull Function<HuskSync, PluginCommand> supplier) {
+            this.commandSupplier = supplier;
+        }
+
+        @NotNull
+        public PluginCommand supply(@NotNull HuskSync plugin) {
+            return commandSupplier.apply(plugin);
+        }
+
+        @NotNull
+        public static PluginCommand[] create(@NotNull HuskSync plugin) {
+            return Arrays.stream(values()).map(type -> type.supply(plugin))
+                    .filter(command -> !plugin.getSettings().isCommandDisabled(command))
+                    .toArray(PluginCommand[]::new);
+        }
+
+    }
+
+}

common/src/main/java/net/william278/husksync/command/TabProvider.java

@@ -1,50 +0,0 @@
-/*
- * This file is part of HuskSync, licensed under the Apache License 2.0.
- *
- *  Copyright (c) William278 <will27528@gmail.com>
- *  Copyright (c) contributors
- *
- *  Licensed under the Apache License, Version 2.0 (the "License");
- *  you may not use this file except in compliance with the License.
- *  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- *  Unless required by applicable law or agreed to in writing, software
- *  distributed under the License is distributed on an "AS IS" BASIS,
- *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- *  See the License for the specific language governing permissions and
- *  limitations under the License.
- */
-
-package net.william278.husksync.command;
-
-import net.william278.husksync.user.CommandUser;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-
-import java.util.List;
-
-public interface TabProvider {
-
-    @Nullable
-    List<String> suggest(@NotNull CommandUser user, @NotNull String[] args);
-
-    @NotNull
-    default List<String> getSuggestions(@NotNull CommandUser user, @NotNull String[] args) {
-        List<String> suggestions = suggest(user, args);
-        if (suggestions == null) {
-            suggestions = List.of();
-        }
-        return filter(suggestions, args);
-    }
-
-    @NotNull
-    default List<String> filter(@NotNull List<String> suggestions, @NotNull String[] args) {
-        return suggestions.stream()
-                .filter(suggestion -> args.length == 0 || suggestion.toLowerCase()
-                        .startsWith(args[args.length - 1].toLowerCase().trim()))
-                .toList();
-    }
-
-}

common/src/main/java/net/william278/husksync/command/UserDataCommand.java

@@ -19,6 +19,7 @@
 
 package net.william278.husksync.command;
 
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
 import net.william278.husksync.HuskSync;
 import net.william278.husksync.data.DataSnapshot;
 import net.william278.husksync.redis.RedisKeyType;
@@ -28,83 +29,32 @@ import net.william278.husksync.user.User;
 import net.william278.husksync.util.DataDumper;
 import net.william278.husksync.util.DataSnapshotList;
 import net.william278.husksync.util.DataSnapshotOverview;
+import net.william278.uniform.BaseCommand;
+import net.william278.uniform.CommandProvider;
+import net.william278.uniform.Permission;
+import net.william278.uniform.element.ArgumentElement;
 import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
-import java.util.*;
+import java.util.List;
+import java.util.Locale;
+import java.util.Optional;
+import java.util.UUID;
 import java.util.logging.Level;
 
-public class UserDataCommand extends Command implements TabProvider {
-
-    private static final Map<String, Boolean> SUB_COMMANDS = Map.of(
-            "view", false,
-            "list", false,
-            "delete", true,
-            "restore", true,
-            "pin", true,
-            "dump", true
-    );
+public class UserDataCommand extends PluginCommand {
 
     public UserDataCommand(@NotNull HuskSync plugin) {
-        super("userdata", List.of("playerdata"), String.format(
-                "<%s> [username] [version_uuid]", String.join("/", SUB_COMMANDS.keySet())
-        ), plugin);
-        setOperatorCommand(true);
-        addAdditionalPermissions(SUB_COMMANDS);
+        super("userdata", List.of("playerdata"), Permission.Default.IF_OP, plugin);
     }
 
     @Override
-    public void execute(@NotNull CommandUser executor, @NotNull String[] args) {
-        final String subCommand = parseStringArg(args, 0).orElse("view").toLowerCase(Locale.ENGLISH);
-        final Optional<User> optionalUser = parseStringArg(args, 1)
-                .flatMap(name -> plugin.getDatabase().getUserByName(name))
-                .or(() -> parseStringArg(args, 0).flatMap(name -> plugin.getDatabase().getUserByName(name)))
-                .or(() -> args.length < 2 && executor instanceof User userExecutor
-                        ? Optional.of(userExecutor) : Optional.empty());
-        final Optional<UUID> uuid = parseUUIDArg(args, 2).or(() -> parseUUIDArg(args, 1));
-        if (optionalUser.isEmpty()) {
-            plugin.getLocales().getLocale("error_invalid_player")
-                    .ifPresent(executor::sendMessage);
-            return;
-        }
-
-        final User user = optionalUser.get();
-        switch (subCommand) {
-            case "view" -> uuid.ifPresentOrElse(
-                    version -> viewSnapshot(executor, user, version),
-                    () -> viewLatestSnapshot(executor, user)
-            );
-            case "list" -> listSnapshots(
-                    executor, user, parseIntArg(args, 2).or(() -> parseIntArg(args, 1)).orElse(1)
-            );
-            case "delete" -> uuid.ifPresentOrElse(
-                    version -> deleteSnapshot(executor, user, version),
-                    () -> plugin.getLocales().getLocale("error_invalid_syntax",
-                                    "/userdata delete <username> <version_uuid>")
-                            .ifPresent(executor::sendMessage)
-            );
-            case "restore" -> uuid.ifPresentOrElse(
-                    version -> restoreSnapshot(executor, user, version),
-                    () -> plugin.getLocales().getLocale("error_invalid_syntax",
-                                    "/userdata restore <username> <version_uuid>")
-                            .ifPresent(executor::sendMessage)
-            );
-            case "pin" -> uuid.ifPresentOrElse(
-                    version -> pinSnapshot(executor, user, version),
-                    () -> plugin.getLocales().getLocale("error_invalid_syntax",
-                                    "/userdata pin <username> <version_uuid>")
-                            .ifPresent(executor::sendMessage)
-            );
-            case "dump" -> uuid.ifPresentOrElse(
-                    version -> dumpSnapshot(executor, user, version, parseStringArg(args, 3)
-                            .map(arg -> arg.equalsIgnoreCase("web")).orElse(false)),
-                    () -> plugin.getLocales().getLocale("error_invalid_syntax",
-                                    "/userdata dump <web/file> <username> <version_uuid>")
-                            .ifPresent(executor::sendMessage)
-            );
-            default -> plugin.getLocales().getLocale("error_invalid_syntax", getUsage())
-                    .ifPresent(executor::sendMessage);
-        }
+    public void provide(@NotNull BaseCommand<?> command) {
+        command.addSubCommand("view", needsOp("view"), view());
+        command.addSubCommand("list", needsOp("list"), list());
+        command.addSubCommand("delete", needsOp("delete"), delete());
+        command.addSubCommand("restore", needsOp("restore"), restore());
+        command.addSubCommand("pin", needsOp("pin"), pin());
+        command.addSubCommand("dump", needsOp("dump"), dump());
     }
 
     // Show the latest snapshot
@@ -224,7 +174,8 @@ public class UserDataCommand extends Command implements TabProvider {
     }
 
     // Dump a snapshot
-    private void dumpSnapshot(@NotNull CommandUser executor, @NotNull User user, @NotNull UUID version, boolean webDump) {
+    private void dumpSnapshot(@NotNull CommandUser executor, @NotNull User user, @NotNull UUID version,
+                              @NotNull DumpType type) {
         final Optional<DataSnapshot.Packed> data = plugin.getDatabase().getSnapshot(user, version);
         if (data.isEmpty()) {
             plugin.getLocales().getLocale("error_invalid_version_uuid")
@@ -237,22 +188,99 @@ public class UserDataCommand extends Command implements TabProvider {
         final DataDumper dumper = DataDumper.create(userData, user, plugin);
         try {
             plugin.getLocales().getLocale("data_dumped", userData.getShortId(), user.getUsername(),
-                    (webDump ? dumper.toWeb() : dumper.toFile())).ifPresent(executor::sendMessage);
+                            (type == DumpType.WEB ? dumper.toWeb() : dumper.toFile()))
+                    .ifPresent(executor::sendMessage);
         } catch (Throwable e) {
             plugin.log(Level.SEVERE, "Failed to dump user data", e);
         }
     }
 
-    @Nullable
-    @Override
-    public List<String> suggest(@NotNull CommandUser executor, @NotNull String[] args) {
-        return switch (args.length) {
-            case 0, 1 -> SUB_COMMANDS.keySet().stream().sorted().toList();
-            case 2 -> plugin.getOnlineUsers().stream().map(User::getUsername).toList();
-            case 4 -> parseStringArg(args, 0)
-                    .map(arg -> arg.equalsIgnoreCase("dump") ? List.of("web", "file") : null)
-                    .orElse(null);
-            default -> null;
+    @NotNull
+    private CommandProvider view() {
+        return (sub) -> {
+            sub.addSyntax((ctx) -> {
+                final User user = ctx.getArgument("username", User.class);
+                viewLatestSnapshot(user(sub, ctx), user);
+            }, user("username"));
+            sub.addSyntax((ctx) -> {
+                final User user = ctx.getArgument("username", User.class);
+                final UUID version = ctx.getArgument("version", UUID.class);
+                viewSnapshot(user(sub, ctx), user, version);
+            }, user("username"), uuid("version"));
         };
     }
+
+    @NotNull
+    private CommandProvider list() {
+        return (sub) -> {
+            sub.addSyntax((ctx) -> {
+                final User user = ctx.getArgument("username", User.class);
+                listSnapshots(user(sub, ctx), user, 1);
+            }, user("username"));
+            sub.addSyntax((ctx) -> {
+                final User user = ctx.getArgument("username", User.class);
+                final int page = ctx.getArgument("page", Integer.class);
+                listSnapshots(user(sub, ctx), user, page);
+            }, user("username"), BaseCommand.intNum("page", 1));
+        };
+    }
+
+    @NotNull
+    private CommandProvider delete() {
+        return (sub) -> sub.addSyntax((ctx) -> {
+            final User user = ctx.getArgument("username", User.class);
+            final UUID version = ctx.getArgument("version", UUID.class);
+            deleteSnapshot(user(sub, ctx), user, version);
+        }, user("username"), uuid("version"));
+    }
+
+    @NotNull
+    private CommandProvider restore() {
+        return (sub) -> sub.addSyntax((ctx) -> {
+            final User user = ctx.getArgument("username", User.class);
+            final UUID version = ctx.getArgument("version", UUID.class);
+            restoreSnapshot(user(sub, ctx), user, version);
+        }, user("username"), uuid("version"));
+    }
+
+    @NotNull
+    private CommandProvider pin() {
+        return (sub) -> sub.addSyntax((ctx) -> {
+            final User user = ctx.getArgument("username", User.class);
+            final UUID version = ctx.getArgument("version", UUID.class);
+            pinSnapshot(user(sub, ctx), user, version);
+        }, user("username"), uuid("version"));
+    }
+
+    @NotNull
+    private CommandProvider dump() {
+        return (sub) -> sub.addSyntax((ctx) -> {
+            final User user = ctx.getArgument("username", User.class);
+            final UUID version = ctx.getArgument("version", UUID.class);
+            final DumpType type = ctx.getArgument("type", DumpType.class);
+            dumpSnapshot(user(sub, ctx), user, version, type);
+        }, user("username"), uuid("version"), dumpType());
+    }
+
+    private <S> ArgumentElement<S, DumpType> dumpType() {
+        return new ArgumentElement<>("type", reader -> {
+            final String type = reader.readString();
+            return switch (type.toLowerCase(Locale.ENGLISH)) {
+                case "web" -> DumpType.WEB;
+                case "file" -> DumpType.FILE;
+                default -> throw CommandSyntaxException.BUILT_IN_EXCEPTIONS
+                        .dispatcherUnknownArgument().createWithContext(reader);
+            };
+        }, (context, builder) -> {
+            builder.suggest("web");
+            builder.suggest("file");
+            return builder.buildFuture();
+        });
+    }
+
+    enum DumpType {
+        WEB,
+        FILE
+    }
+
 }

common/src/main/java/net/william278/husksync/config/Settings.java

@@ -25,6 +25,7 @@ import de.exlll.configlib.Configuration;
 import lombok.AccessLevel;
 import lombok.Getter;
 import lombok.NoArgsConstructor;
+import net.william278.husksync.command.PluginCommand;
 import net.william278.husksync.data.DataSnapshot;
 import net.william278.husksync.data.Identifier;
 import net.william278.husksync.database.Database;
@@ -69,15 +70,15 @@ public class Settings {
     @Comment("Enable development debug logging")
     private boolean debugLogging = false;
 
-    @Comment("Whether to provide modern, rich TAB suggestions for commands (if available)")
-    private boolean brigadierTabCompletion = false;
-
     @Comment({"Whether to enable the Player Analytics hook.", "Docs: https://william278.net/docs/husksync/plan-hook"})
     private boolean enablePlanHook = true;
 
-    @Comment("Whether to cancel game event packets directly when handling locked players if ProtocolLib is installed")
+    @Comment("Whether to cancel game event packets directly when handling locked players if ProtocolLib or PacketEvents is installed")
     private boolean cancelPackets = true;
 
+    @Comment("Add HuskSync commands to this list to prevent them from being registered (e.g. ['userdata'])")
+    @Getter(AccessLevel.NONE)
+    private List<String> disabledCommands = Lists.newArrayList();
 
     // Database settings
     @Comment("Database settings")
@@ -185,7 +186,7 @@ public class Settings {
     }
 
     // Synchronization settings
-    @Comment("Redis settings")
+    @Comment("Data syncing settings")
     private SynchronizationSettings synchronization = new SynchronizationSettings();
 
     @Getter
@@ -297,4 +298,10 @@ public class Settings {
         }
     }
 
+    public boolean isCommandDisabled(@NotNull PluginCommand command) {
+        return disabledCommands.stream().map(c -> c.startsWith("/") ? c.substring(1) : c)
+                .anyMatch(c -> c.equalsIgnoreCase(command.getName()) || command.getAliases().contains(c));
+    }
+
+
 }

common/src/main/java/net/william278/husksync/data/Data.java

@@ -21,6 +21,11 @@ package net.william278.husksync.data;
 
 import com.google.common.collect.Sets;
 import com.google.gson.annotations.SerializedName;
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.experimental.Accessors;
 import net.kyori.adventure.key.Key;
 import net.william278.husksync.HuskSync;
 import net.william278.husksync.user.OnlineUser;
@@ -78,6 +83,7 @@ public interface Data {
          */
         interface Inventory extends Items {
 
+            int INVENTORY_SLOT_COUNT = 41;
             String ITEMS_TAG = "items";
             String HELD_ITEM_SLOT_TAG = "held_item_slot";
 
@@ -110,7 +116,7 @@ public interface Data {
          * Data container holding data for ender chests
          */
         interface EnderChest extends Items {
-
+            int ENDER_CHEST_SLOT_COUNT = 27;
         }
 
     }
@@ -149,14 +155,14 @@ public interface Data {
      */
     interface Advancements extends Data {
 
+        String RECIPE_ADVANCEMENT = "minecraft:recipe";
+
         @NotNull
         List<Advancement> getCompleted();
 
         @NotNull
         default List<Advancement> getCompletedExcludingRecipes() {
-            return getCompleted().stream()
-                    .filter(advancement -> !advancement.getKey().startsWith("minecraft:recipe"))
-                    .collect(Collectors.toList());
+            return getCompleted().stream().filter(adv -> !adv.getKey().startsWith(RECIPE_ADVANCEMENT)).toList();
         }
 
         void setCompleted(@NotNull List<Advancement> completed);
@@ -333,17 +339,34 @@ public interface Data {
 
         }
 
-        record Modifier(
-                @NotNull UUID uuid,
-                @NotNull String name,
-                double amount,
-                @SerializedName("operation") int operationType,
-                @SerializedName("equipment_slot") int equipmentSlot
-        ) {
+        @Getter
+        @Accessors(fluent = true)
+        @AllArgsConstructor
+        @NoArgsConstructor
+        final class Modifier {
+            @Getter(AccessLevel.NONE)
+            @Nullable
+            @SerializedName("uuid")
+            private UUID uuid;
+            @SerializedName("name")
+            private String name;
+            @SerializedName("amount")
+            private double amount;
+            @SerializedName("operation")
+            private int operationType;
+            @SerializedName("equipment_slot")
+            private int equipmentSlot;
+
+            public Modifier(@NotNull String name, double amount, int operationType, int equipmentSlot) {
+                this.name = name;
+                this.amount = amount;
+                this.operationType = operationType;
+                this.equipmentSlot = equipmentSlot;
+            }
 
             @Override
             public boolean equals(Object obj) {
-                return obj instanceof Modifier modifier && modifier.uuid.equals(uuid);
+                return obj instanceof Modifier modifier && modifier.uuid().equals(uuid());
             }
 
             public double modify(double value) {
@@ -354,6 +377,12 @@ public interface Data {
                     default -> value;
                 };
             }
+
+            @NotNull
+            public UUID uuid() {
+                return uuid != null ? uuid : UUID.nameUUIDFromBytes(name.getBytes());
+            }
+
         }
 
         default Optional<Attribute> getAttribute(@NotNull Key key) {

common/src/main/java/net/william278/husksync/data/DataHolder.java

@@ -30,8 +30,8 @@ public interface DataHolder {
     @NotNull
     Map<Identifier, Data> getData();
 
-    default Optional<? extends Data> getData(@NotNull Identifier identifier) {
-        return Optional.ofNullable(getData().get(identifier));
+    default Optional<? extends Data> getData(@NotNull Identifier id) {
+        return getData().entrySet().stream().filter(e -> e.getKey().equals(id)).map(Map.Entry::getValue).findFirst();
     }
 
     default void setData(@NotNull Identifier identifier, @NotNull Data data) {

common/src/main/java/net/william278/husksync/data/DataSnapshot.java

@@ -370,7 +370,7 @@ public class DataSnapshot {
     public static class Unpacked extends DataSnapshot implements DataHolder {
 
         @Expose(serialize = false, deserialize = false)
-        private final Map<Identifier, Data> deserialized;
+        private final TreeMap<Identifier, Data> deserialized;
 
         private Unpacked(@NotNull UUID id, boolean pinned, @NotNull OffsetDateTime timestamp,
                          @NotNull String saveCause, @NotNull String serverName, @NotNull Map<String, String> data,
@@ -381,7 +381,7 @@ public class DataSnapshot {
         }
 
         private Unpacked(@NotNull UUID id, boolean pinned, @NotNull OffsetDateTime timestamp,
-                         @NotNull String saveCause, @NotNull String serverName, @NotNull Map<Identifier, Data> data,
+                         @NotNull String saveCause, @NotNull String serverName, @NotNull TreeMap<Identifier, Data> data,
                          @NotNull Version minecraftVersion, @NotNull String platformType, int formatVersion) {
             super(id, pinned, timestamp, saveCause, serverName, Map.of(), minecraftVersion, platformType, formatVersion);
             this.deserialized = data;
@@ -389,25 +389,25 @@ public class DataSnapshot {
 
         @NotNull
         @ApiStatus.Internal
-        private Map<Identifier, Data> deserializeData(@NotNull HuskSync plugin) {
+        private TreeMap<Identifier, Data> deserializeData(@NotNull HuskSync plugin) {
             return data.entrySet().stream()
-                    .map((entry) -> plugin.getIdentifier(entry.getKey()).map(id -> Map.entry(
-                            id, plugin.getSerializers().get(id).deserialize(entry.getValue(), getMinecraftVersion())
-                    )).orElse(null))
-                    .filter(Objects::nonNull)
-                    .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
+                    .filter(e -> plugin.getIdentifier(e.getKey()).isPresent())
+                    .map(entry -> Map.entry(plugin.getIdentifier(entry.getKey()).orElseThrow(), entry.getValue()))
+                    .collect(Collectors.toMap(
+                            Map.Entry::getKey,
+                            entry -> plugin.deserializeData(entry.getKey(), entry.getValue(), getMinecraftVersion()),
+                            (a, b) -> b, () -> Maps.newTreeMap(SerializerRegistry.DEPENDENCY_ORDER_COMPARATOR)
+                    ));
         }
 
         @NotNull
         @ApiStatus.Internal
         private Map<String, String> serializeData(@NotNull HuskSync plugin) {
             return deserialized.entrySet().stream()
-                    .map((entry) -> Map.entry(entry.getKey().toString(),
-                            Objects.requireNonNull(
-                                    plugin.getSerializers().get(entry.getKey()),
-                                    String.format("No serializer found for %s", entry.getKey())
-                            ).serialize(entry.getValue())))
-                    .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
+                    .collect(Collectors.toMap(
+                            entry -> entry.getKey().toString(),
+                            entry -> plugin.serializeData(entry.getKey(), entry.getValue())
+                    ));
         }
 
         /**
@@ -453,12 +453,12 @@ public class DataSnapshot {
         private String serverName;
         private boolean pinned;
         private OffsetDateTime timestamp;
-        private final Map<Identifier, Data> data;
+        private final TreeMap<Identifier, Data> data;
 
         private Builder(@NotNull HuskSync plugin) {
             this.plugin = plugin;
             this.pinned = false;
-            this.data = Maps.newHashMap();
+            this.data = Maps.newTreeMap(SerializerRegistry.DEPENDENCY_ORDER_COMPARATOR);
             this.timestamp = OffsetDateTime.now();
             this.id = UUID.randomUUID();
             this.serverName = plugin.getServerName();

common/src/main/java/net/william278/husksync/data/Identifier.java

@@ -19,40 +19,82 @@
 
 package net.william278.husksync.data;
 
+import lombok.*;
 import net.kyori.adventure.key.InvalidKeyException;
 import net.kyori.adventure.key.Key;
 import org.intellij.lang.annotations.Subst;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
+import java.util.Collections;
+import java.util.Comparator;
 import java.util.Map;
+import java.util.Set;
 import java.util.stream.Stream;
 
 /**
  * Identifiers of different types of {@link Data}s
  */
+@Getter
 public class Identifier {
 
-    public static Identifier INVENTORY = huskSync("inventory", true);
-    public static Identifier ENDER_CHEST = huskSync("ender_chest", true);
-    public static Identifier POTION_EFFECTS = huskSync("potion_effects", true);
-    public static Identifier ADVANCEMENTS = huskSync("advancements", true);
-    public static Identifier LOCATION = huskSync("location", false);
-    public static Identifier STATISTICS = huskSync("statistics", true);
-    public static Identifier HEALTH = huskSync("health", true);
-    public static Identifier HUNGER = huskSync("hunger", true);
-    public static Identifier ATTRIBUTES = huskSync("attributes", true);
-    public static Identifier EXPERIENCE = huskSync("experience", true);
-    public static Identifier GAME_MODE = huskSync("game_mode", true);
-    public static Identifier FLIGHT_STATUS = huskSync("flight_status", true);
-    public static Identifier PERSISTENT_DATA = huskSync("persistent_data", true);
+    // Built-in identifiers
+    public static final Identifier PERSISTENT_DATA = huskSync("persistent_data", true);
+    public static final Identifier INVENTORY = huskSync("inventory", true);
+    public static final Identifier ENDER_CHEST = huskSync("ender_chest", true);
+    public static final Identifier ADVANCEMENTS = huskSync("advancements", true);
+    public static final Identifier STATISTICS = huskSync("statistics", true);
+    public static final Identifier POTION_EFFECTS = huskSync("potion_effects", true);
+    public static final Identifier GAME_MODE = huskSync("game_mode", true);
+    public static final Identifier FLIGHT_STATUS = huskSync("flight_status", true,
+            Dependency.optional("game_mode")
+    );
+    public static final Identifier ATTRIBUTES = huskSync("attributes", true,
+            Dependency.required("potion_effects")
+    );
+    public static final Identifier HEALTH = huskSync("health", true,
+            Dependency.optional("attributes")
+    );
+    public static final Identifier HUNGER = huskSync("hunger", true,
+            Dependency.optional("attributes")
+    );
+    public static final Identifier EXPERIENCE = huskSync("experience", true,
+            Dependency.optional("advancements")
+    );
+    public static final Identifier LOCATION = huskSync("location", false,
+            Dependency.optional("flight_status"),
+            Dependency.optional("potion_effects")
+    );
 
     private final Key key;
-    private final boolean configDefault;
+    private final boolean enabledByDefault;
+    @Getter
+    private final Set<Dependency> dependencies;
+    @Setter
+    @Getter
+    public boolean enabled;
 
-    private Identifier(@NotNull Key key, boolean configDefault) {
+    private Identifier(@NotNull Key key, boolean enabledByDefault, @NotNull Set<Dependency> dependencies) {
         this.key = key;
-        this.configDefault = configDefault;
+        this.enabledByDefault = enabledByDefault;
+        this.enabled = enabledByDefault;
+        this.dependencies = dependencies;
+    }
+
+    /**
+     * Create an identifier from a {@link Key}
+     *
+     * @param key          the key
+     * @param dependencies the dependencies
+     * @return the identifier
+     * @since 3.5.4
+     */
+    @NotNull
+    public static Identifier from(@NotNull Key key, @NotNull Set<Dependency> dependencies) {
+        if (key.namespace().equals("husksync")) {
+            throw new IllegalArgumentException("You cannot register a key with \"husksync\" as the namespace!");
+        }
+        return new Identifier(key, true, dependencies);
     }
 
     /**
@@ -64,10 +106,7 @@ public class Identifier {
      */
     @NotNull
     public static Identifier from(@NotNull Key key) {
-        if (key.namespace().equals("husksync")) {
-            throw new IllegalArgumentException("You cannot register a key with \"husksync\" as the namespace!");
-        }
-        return new Identifier(key, true);
+        return from(key, Collections.emptySet());
     }
 
     /**
@@ -83,25 +122,34 @@ public class Identifier {
         return from(Key.key(plugin, name));
     }
 
+    /**
+     * Create an identifier from a namespace, value, and dependencies
+     *
+     * @param plugin       the namespace
+     * @param name         the value
+     * @param dependencies the dependencies
+     * @return the identifier
+     * @since 3.5.4
+     */
+    @NotNull
+    public static Identifier from(@Subst("plugin") @NotNull String plugin, @Subst("null") @NotNull String name,
+                                  @NotNull Set<Dependency> dependencies) {
+        return from(Key.key(plugin, name), dependencies);
+    }
+
+    // Return an identifier with a HuskSync namespace
     @NotNull
     private static Identifier huskSync(@Subst("null") @NotNull String name,
                                        boolean configDefault) throws InvalidKeyException {
-        return new Identifier(Key.key("husksync", name), configDefault);
+        return new Identifier(Key.key("husksync", name), configDefault, Collections.emptySet());
     }
 
+    // Return an identifier with a HuskSync namespace
     @NotNull
-    @SuppressWarnings("unused")
-    private static Identifier parse(@NotNull String key) throws InvalidKeyException {
-        return huskSync(key, true);
-    }
-
-    public boolean isEnabledByDefault() {
-        return configDefault;
-    }
-
-    @NotNull
-    private Map.Entry<String, Boolean> getConfigEntry() {
-        return Map.entry(getKeyValue(), configDefault);
+    private static Identifier huskSync(@Subst("null") @NotNull String name,
+                                       @SuppressWarnings("SameParameterValue") boolean configDefault,
+                                       @NotNull Dependency... dependents) throws InvalidKeyException {
+        return new Identifier(Key.key("husksync", name), configDefault, Set.of(dependents));
     }
 
     /**
@@ -122,6 +170,17 @@ public class Identifier {
                 .toArray(Map.Entry[]::new));
     }
 
+    /**
+     * Returns {@code true} if the identifier depends on the given identifier
+     *
+     * @param identifier the identifier to check
+     * @return {@code true} if the identifier depends on the given identifier
+     * @since 3.5.4
+     */
+    public boolean dependsOn(@NotNull Identifier identifier) {
+        return dependencies.contains(Dependency.required(identifier.key));
+    }
+
     /**
      * Get the namespace of the identifier
      *
@@ -176,4 +235,85 @@ public class Identifier {
         return false;
     }
 
+    // Get the config entry for the identifier
+    @NotNull
+    private Map.Entry<String, Boolean> getConfigEntry() {
+        return Map.entry(getKeyValue(), enabledByDefault);
+    }
+
+    /**
+     * Compares two identifiers based on their dependencies.
+     * <p>
+     * If this identifier contains a dependency on the other, it should come after & vice versa
+     *
+     * @since 3.5.4
+     */
+    @NoArgsConstructor(access = AccessLevel.PACKAGE)
+    static class DependencyOrderComparator implements Comparator<Identifier> {
+
+        @Override
+        public int compare(@NotNull Identifier i1, @NotNull Identifier i2) {
+            if (i1.equals(i2)) {
+                return 0;
+            }
+            if (i1.dependsOn(i2)) {
+                if (i2.dependsOn(i1)) {
+                    throw new IllegalArgumentException(
+                            "Found circular dependency between %s and %s".formatted(i1.getKey(), i2.getKey())
+                    );
+                }
+                return 1;
+            }
+            return -1;
+        }
+
+    }
+
+    /**
+     * Represents a data dependency of an identifier, used to determine the order in which data is applied to users
+     *
+     * @since 3.5.4
+     */
+    @Getter
+    @AllArgsConstructor(access = AccessLevel.PRIVATE)
+    public static class Dependency {
+        /**
+         * Key of the data dependency see {@code Identifier#key()}
+         */
+        private Key key;
+        /**
+         * Whether the data dependency is required to be present & enabled for the dependant data to enabled
+         */
+        private boolean required;
+
+        @NotNull
+        protected static Dependency required(@NotNull Key identifier) {
+            return new Dependency(identifier, true);
+        }
+
+        @NotNull
+        public static Dependency optional(@NotNull Key identifier) {
+            return new Dependency(identifier, false);
+        }
+
+        @NotNull
+        @SuppressWarnings("SameParameterValue")
+        private static Dependency required(@Subst("null") @NotNull String identifier) {
+            return required(Key.key("husksync", identifier));
+        }
+
+        @NotNull
+        private static Dependency optional(@Subst("null") @NotNull String identifier) {
+            return optional(Key.key("husksync", identifier));
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (obj instanceof Dependency other) {
+                return key.equals(other.key);
+            }
+            return false;
+        }
+    }
+
 }

common/src/main/java/net/william278/husksync/data/Serializer.java

@@ -20,6 +20,8 @@
 package net.william278.husksync.data;
 
 import net.william278.desertwell.util.Version;
+import net.william278.husksync.HuskSync;
+import net.william278.husksync.adapter.Adaptable;
 import org.jetbrains.annotations.NotNull;
 
 public interface Serializer<T extends Data> {
@@ -46,4 +48,26 @@ public interface Serializer<T extends Data> {
     }
 
 
+    class Json<T extends Data & Adaptable> implements Serializer<T> {
+
+        private final HuskSync plugin;
+        private final Class<T> type;
+
+        public Json(@NotNull HuskSync plugin, @NotNull Class<T> type) {
+            this.type = type;
+            this.plugin = plugin;
+        }
+
+        @Override
+        public T deserialize(@NotNull String serialized) throws DeserializationException {
+            return plugin.getDataAdapter().fromJson(serialized, type);
+        }
+
+        @NotNull
+        @Override
+        public String serialize(@NotNull T element) throws SerializationException {
+            return plugin.getDataAdapter().toJson(element);
+        }
+
+    }
 }

common/src/main/java/net/william278/husksync/data/SerializerRegistry.java

@@ -0,0 +1,174 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.data;
+
+import net.william278.desertwell.util.Version;
+import net.william278.husksync.HuskSync;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.*;
+import java.util.logging.Level;
+
+public interface SerializerRegistry {
+
+    // Comparator for ordering identifiers based on dependency
+    @NotNull
+    @ApiStatus.Internal
+    Comparator<Identifier> DEPENDENCY_ORDER_COMPARATOR = new Identifier.DependencyOrderComparator();
+
+    /**
+     * Returns the data serializer for the given {@link Identifier}
+     *
+     * @since 3.0
+     */
+    @NotNull
+    <T extends Data> TreeMap<Identifier, Serializer<T>> getSerializers();
+
+    /**
+     * Register a data serializer for the given {@link Identifier}
+     *
+     * @param id         the {@link Identifier}
+     * @param serializer the {@link Serializer}
+     * @since 3.0
+     */
+    @SuppressWarnings("unchecked")
+    default void registerSerializer(@NotNull Identifier id, @NotNull Serializer<? extends Data> serializer) {
+        if (id.isCustom()) {
+            getPlugin().log(Level.INFO, "Registered custom data type: %s".formatted(id));
+        }
+        id.setEnabled(id.isCustom() || getPlugin().getSettings().getSynchronization().isFeatureEnabled(id));
+        getSerializers().put(id, (Serializer<Data>) serializer);
+    }
+
+    /**
+     * Ensure dependencies for identifiers that have required dependencies are met
+     * <p>
+     * This checks the dependencies of all registered identifiers and throws an {@link IllegalStateException}
+     * if a dependency has not been registered or enabled via the config
+     *
+     * @since 3.5.4
+     */
+    default void validateDependencies() throws IllegalStateException {
+        getSerializers().keySet().stream().filter(Identifier::isEnabled)
+                .forEach(identifier -> {
+                    final List<String> unmet = identifier.getDependencies().stream()
+                            .filter(Identifier.Dependency::isRequired)
+                            .filter(dep -> !isDataTypeAvailable(dep.getKey().asString()))
+                            .map(dep -> dep.getKey().asString()).toList();
+                    if (!unmet.isEmpty()) {
+                        identifier.setEnabled(false);
+                        getPlugin().log(Level.WARNING, "Disabled %s syncing as the following types need to be on: %s"
+                                .formatted(identifier, String.join(", ", unmet)));
+                    }
+                });
+    }
+
+    /**
+     * Get the {@link Identifier} for the given key
+     *
+     * @since 3.0
+     */
+    default Optional<Identifier> getIdentifier(@NotNull String key) {
+        return getSerializers().keySet().stream()
+                .filter(id -> id.getKey().asString().equals(key)).findFirst();
+    }
+
+    /**
+     * Get a data serializer for the given {@link Identifier}
+     *
+     * @param identifier the {@link Identifier} to get the serializer for
+     * @return the {@link Serializer} for the given {@link Identifier}
+     * @since 3.5.4
+     */
+    default Optional<Serializer<Data>> getSerializer(@NotNull Identifier identifier) {
+        return getSerializers().entrySet().stream()
+                .filter(entry -> entry.getKey().getKey().equals(identifier.getKey()))
+                .map(Map.Entry::getValue).findFirst();
+    }
+
+    /**
+     * Serialize data for the given {@link Identifier}
+     *
+     * @param identifier the {@link Identifier} to serialize data for
+     * @param data       the data to serialize
+     * @return the serialized data
+     * @throws IllegalArgumentException if no serializer is found for the given {@link Identifier}
+     * @since 3.5.4
+     */
+    @NotNull
+    default String serializeData(@NotNull Identifier identifier, @NotNull Data data) throws IllegalStateException {
+        return getSerializer(identifier).map(serializer -> serializer.serialize(data))
+                .orElseThrow(() -> new IllegalStateException("No serializer found for %s".formatted(identifier)));
+    }
+
+    /**
+     * Deserialize data of a given {@link Version Minecraft version} for the given {@link Identifier data identifier}
+     *
+     * @param identifier    the {@link Identifier} to deserialize data for
+     * @param data          the data to deserialize
+     * @param dataMcVersion the Minecraft version of the data
+     * @return the deserialized data
+     * @throws IllegalStateException if no serializer is found for the given {@link Identifier}
+     * @since 3.6.4
+     */
+    @NotNull
+    default Data deserializeData(@NotNull Identifier identifier, @NotNull String data,
+                                 @NotNull Version dataMcVersion) throws IllegalStateException {
+        return getSerializer(identifier).map(serializer -> serializer.deserialize(data, dataMcVersion)).orElseThrow(
+                () -> new IllegalStateException("No serializer found for %s".formatted(identifier))
+        );
+    }
+
+    /**
+     * Deserialize data for the given {@link Identifier data identifier}
+     *
+     * @param identifier the {@link Identifier} to deserialize data for
+     * @param data       the data to deserialize
+     * @return the deserialized data
+     * @since 3.5.4
+     * @deprecated Use {@link #deserializeData(Identifier, String, Version)} instead
+     */
+    @NotNull
+    @Deprecated(since = "3.6.5")
+    default Data deserializeData(@NotNull Identifier identifier, @NotNull String data) {
+        return deserializeData(identifier, data, getPlugin().getMinecraftVersion());
+    }
+
+    /**
+     * Get the set of registered data types
+     *
+     * @return the set of registered data types
+     * @since 3.0
+     */
+    @NotNull
+    default Set<Identifier> getRegisteredDataTypes() {
+        return getSerializers().keySet();
+    }
+
+    // Returns if a data type is available and enabled in the config
+    private boolean isDataTypeAvailable(@NotNull String key) {
+        return getIdentifier(key).map(Identifier::isEnabled).orElse(false);
+    }
+
+    @NotNull
+    HuskSync getPlugin();
+
+}

common/src/main/java/net/william278/husksync/data/UserDataHolder.java

@@ -34,7 +34,7 @@ import java.util.logging.Level;
 public interface UserDataHolder extends DataHolder {
 
     /**
-     * Get the data that is enabled for syncing in the config
+     * Get the data enabled for syncing in the config
      *
      * @return the data that is enabled for syncing
      * @since 3.0
@@ -43,7 +43,7 @@ public interface UserDataHolder extends DataHolder {
     @NotNull
     default Map<Identifier, Data> getData() {
         return getPlugin().getRegisteredDataTypes().stream()
-                .filter(type -> type.isCustom() || getPlugin().getSettings().getSynchronization().isFeatureEnabled(type))
+                .filter(Identifier::isEnabled)
                 .map(id -> Map.entry(id, getData(id)))
                 .filter(data -> data.getValue().isPresent())
                 .collect(HashMap::new, (map, data) -> map.put(data.getKey(), data.getValue().get()), HashMap::putAll);
@@ -79,7 +79,8 @@ public interface UserDataHolder extends DataHolder {
      * Deserialize and apply a data snapshot to this data owner
      * <p>
      * This method will deserialize the data on the current thread, then synchronously apply it on
-     * the main server thread.
+     * the main server thread. The order data will be applied is determined based on the dependencies of
+     * each data type (see {@link Identifier.Dependency}).
      * </p>
      * The {@code runAfter} callback function will be run after the snapshot has been applied.
      *
@@ -106,12 +107,15 @@ public interface UserDataHolder extends DataHolder {
             try {
                 for (Map.Entry<Identifier, Data> entry : unpacked.getData().entrySet()) {
                     final Identifier identifier = entry.getKey();
-                    if (plugin.getSettings().getSynchronization().isFeatureEnabled(identifier)) {
-                        if (identifier.isCustom()) {
-                            getCustomDataStore().put(identifier, entry.getValue());
-                        }
-                        entry.getValue().apply(this, plugin);
+                    if (!identifier.isEnabled()) {
+                        continue;
                     }
+
+                    // Apply the identified data
+                    if (identifier.isCustom()) {
+                        getCustomDataStore().put(identifier, entry.getValue());
+                    }
+                    entry.getValue().apply(this, plugin);
                 }
             } catch (Throwable e) {
                 plugin.log(Level.SEVERE, String.format("Failed to apply data snapshot to %s", getUsername()), e);

common/src/main/java/net/william278/husksync/database/MongoDbDatabase.java

@@ -107,13 +107,13 @@ public class MongoDbDatabase extends Database {
                         if (!existingUser.getUsername().equals(user.getUsername())) {
                             // Update a user's name if it has changed in the database
                             try {
-                                Document filter = new Document("uuid", existingUser.getUuid().toString());
+                                Document filter = new Document("uuid", existingUser.getUuid());
                                 Document doc = mongoCollectionHelper.getCollection(usersTable).find(filter).first();
                                 if (doc == null) {
                                     throw new MongoException("User document returned null!");
                                 }
 
-                                Bson updates = Updates.set("uuid", user.getUuid().toString());
+                                Bson updates = Updates.set("username", user.getUsername());
                                 mongoCollectionHelper.updateDocument(usersTable, doc, updates);
                             } catch (MongoException e) {
                                 plugin.log(Level.SEVERE, "Failed to insert a user into the database", e);
@@ -123,7 +123,7 @@ public class MongoDbDatabase extends Database {
                     () -> {
                         // Insert new player data into the database
                         try {
-                            Document doc = new Document("uuid", user.getUuid().toString()).append("username", user.getUsername());
+                            Document doc = new Document("uuid", user.getUuid()).append("username", user.getUsername());
                             mongoCollectionHelper.insertDocument(usersTable, doc);
                         } catch (MongoException e) {
                             plugin.log(Level.SEVERE, "Failed to insert a user into the database", e);
@@ -148,8 +148,7 @@ public class MongoDbDatabase extends Database {
             Document filter = new Document("uuid", uuid);
             Document doc = mongoCollectionHelper.getCollection(usersTable).find(filter).first();
             if (doc != null) {
-                return Optional.of(new User(UUID.fromString(doc.getString("uuid")),
-                        doc.getString("username")));
+                return Optional.of(new User(uuid, doc.getString("username")));
             }
             return Optional.empty();
         } catch (MongoException e) {
@@ -171,7 +170,7 @@ public class MongoDbDatabase extends Database {
             Document filter = new Document("username", username);
             Document doc = mongoCollectionHelper.getCollection(usersTable).find(filter).first();
             if (doc != null) {
-                return Optional.of(new User(UUID.fromString(doc.getString("uuid")),
+                return Optional.of(new User(doc.get("uuid", UUID.class),
                         doc.getString("username")));
             }
             return Optional.empty();
@@ -191,12 +190,12 @@ public class MongoDbDatabase extends Database {
     @Override
     public Optional<DataSnapshot.Packed> getLatestSnapshot(@NotNull User user) {
         try {
-            Document filter = new Document("player_uuid", user.getUuid().toString());
+            Document filter = new Document("player_uuid", user.getUuid());
             Document sort = new Document("timestamp", -1); // -1 = Descending
             FindIterable<Document> iterable = mongoCollectionHelper.getCollection(userDataTable).find(filter).sort(sort);
             Document doc = iterable.first();
             if (doc != null) {
-                final UUID versionUuid = UUID.fromString(doc.getString("version_uuid"));
+                final UUID versionUuid = doc.get("version_uuid", UUID.class);
                 final OffsetDateTime timestamp = OffsetDateTime.ofInstant(Instant.ofEpochMilli((long) doc.get("timestamp")), TimeZone.getDefault().toZoneId());
                 final Binary bin = doc.get("data", Binary.class);
                 final byte[] dataByteArray = bin.getData();
@@ -221,11 +220,11 @@ public class MongoDbDatabase extends Database {
     public List<DataSnapshot.Packed> getAllSnapshots(@NotNull User user) {
         try {
             final List<DataSnapshot.Packed> retrievedData = Lists.newArrayList();
-            Document filter = new Document("player_uuid", user.getUuid().toString());
+            Document filter = new Document("player_uuid", user.getUuid());
             Document sort = new Document("timestamp", -1); // -1 = Descending
             FindIterable<Document> iterable = mongoCollectionHelper.getCollection(userDataTable).find(filter).sort(sort);
             for (Document doc : iterable) {
-                final UUID versionUuid = UUID.fromString(doc.getString("version_uuid"));
+                final UUID versionUuid = doc.get("version_uuid", UUID.class);
                 final OffsetDateTime timestamp = OffsetDateTime.ofInstant(Instant.ofEpochMilli((long) doc.get("timestamp")), TimeZone.getDefault().toZoneId());
                 final Binary bin = doc.get("data", Binary.class);
                 final byte[] dataByteArray = bin.getData();
@@ -249,7 +248,7 @@ public class MongoDbDatabase extends Database {
     @Override
     public Optional<DataSnapshot.Packed> getSnapshot(@NotNull User user, @NotNull UUID versionUuid) {
         try {
-            Document filter = new Document("player_uuid", user.getUuid().toString()).append("version_uuid", versionUuid.toString());
+            Document filter = new Document("player_uuid", user.getUuid()).append("version_uuid", versionUuid);
             Document sort = new Document("timestamp", -1); // -1 = Descending
             FindIterable<Document> iterable = mongoCollectionHelper.getCollection(userDataTable).find(filter).sort(sort);
             Document doc = iterable.first();
@@ -281,7 +280,7 @@ public class MongoDbDatabase extends Database {
             final int maxSnapshots = plugin.getSettings().getSynchronization().getMaxUserDataSnapshots();
             if (unpinnedUserData.size() > maxSnapshots) {
 
-                Document filter = new Document("player_uuid", user.getUuid().toString()).append("pinned", false);
+                Document filter = new Document("player_uuid", user.getUuid()).append("pinned", false);
                 Document sort = new Document("timestamp", 1); // 1 = Ascending
                 FindIterable<Document> iterable = mongoCollectionHelper.getCollection(userDataTable)
                         .find(filter)
@@ -307,7 +306,7 @@ public class MongoDbDatabase extends Database {
     @Override
     public boolean deleteSnapshot(@NotNull User user, @NotNull UUID versionUuid) {
         try {
-            Document filter = new Document("player_uuid", user.getUuid().toString()).append("version_uuid", versionUuid.toString());
+            Document filter = new Document("player_uuid", user.getUuid()).append("version_uuid", versionUuid);
             Document doc = mongoCollectionHelper.getCollection(userDataTable).find(filter).first();
             if (doc == null) {
                 return false;
@@ -332,7 +331,7 @@ public class MongoDbDatabase extends Database {
     @Override
     protected void rotateLatestSnapshot(@NotNull User user, @NotNull OffsetDateTime within) {
         try {
-            Document filter = new Document("player_uuid", user.getUuid().toString()).append("pinned", false);
+            Document filter = new Document("player_uuid", user.getUuid()).append("pinned", false);
             Document sort = new Document("timestamp", 1); // 1 = Ascending
             FindIterable<Document> iterable = mongoCollectionHelper.getCollection(userDataTable)
                     .find(filter)
@@ -362,8 +361,8 @@ public class MongoDbDatabase extends Database {
     @Override
     protected void createSnapshot(@NotNull User user, @NotNull DataSnapshot.Packed data) {
         try {
-            Document doc = new Document("player_uuid", user.getUuid().toString())
-                    .append("version_uuid", data.getId().toString())
+            Document doc = new Document("player_uuid", user.getUuid())
+                    .append("version_uuid", data.getId())
                     .append("timestamp", data.getTimestamp().toInstant().toEpochMilli())
                     .append("save_cause", data.getSaveCause().name())
                     .append("pinned", data.isPinned())
@@ -384,7 +383,7 @@ public class MongoDbDatabase extends Database {
     @Override
     public void updateSnapshot(@NotNull User user, @NotNull DataSnapshot.Packed data) {
         try {
-            Document doc = new Document("player_uuid", user.getUuid().toString()).append("version_uuid", data.getId().toString());
+            Document doc = new Document("player_uuid", user.getUuid()).append("version_uuid", data.getId());
             Bson updates = Updates.combine(
                     Updates.set("save_cause", data.getSaveCause().name()),
                     Updates.set("pinned", data.isPinned()),

common/src/main/java/net/william278/husksync/event/Cancellable.java

@@ -19,7 +19,6 @@
 
 package net.william278.husksync.event;
 
-@SuppressWarnings("unused")
 public interface Cancellable extends Event {
 
     default boolean isCancelled() {

common/src/main/java/net/william278/husksync/event/PreSyncEvent.java

@@ -27,7 +27,7 @@ import org.jetbrains.annotations.NotNull;
 import java.util.function.Consumer;
 
 @SuppressWarnings("unused")
-public interface PreSyncEvent extends PlayerEvent {
+public interface PreSyncEvent extends PlayerEvent, Cancellable {
 
     @NotNull
     DataSnapshot.Packed getData();

common/src/main/java/net/william278/husksync/listener/EventListener.java

@@ -107,7 +107,7 @@ public abstract class EventListener {
     /**
      * Handle the plugin disabling
      */
-    public final void handlePluginDisable() {
+    public void handlePluginDisable() {
         // Save for all online players
         plugin.getOnlineUsers().stream()
                 .filter(user -> !plugin.isLocked(user.getUuid()) && !user.isNpc())

common/src/main/java/net/william278/husksync/listener/LockedHandler.java

@@ -54,4 +54,16 @@ public interface LockedHandler {
     @ApiStatus.Internal
     HuskSync getPlugin();
 
+    default void onLoad() {
+
+    }
+
+    default void onEnable() {
+
+    }
+
+    default void onDisable() {
+
+    }
+
 }

common/src/main/java/net/william278/husksync/sync/LockstepDataSyncer.java

@@ -59,16 +59,13 @@ public class LockstepDataSyncer extends DataSyncer {
 
     @Override
     public void saveUserData(@NotNull OnlineUser onlineUser) {
-        plugin.runAsync(() -> {
-            getRedis().setUserServerSwitch(onlineUser);
-            saveData(
-                    onlineUser, onlineUser.createSnapshot(DataSnapshot.SaveCause.DISCONNECT),
-                    (user, data) -> {
-                        getRedis().setUserData(user, data, RedisKeyType.TTL_1_YEAR);
-                        getRedis().setUserCheckedOut(user, false);
-                    }
-            );
-        });
+        plugin.runAsync(() -> saveData(
+                onlineUser, onlineUser.createSnapshot(DataSnapshot.SaveCause.DISCONNECT),
+                (user, data) -> {
+                    getRedis().setUserData(user, data, RedisKeyType.TTL_1_YEAR);
+                    getRedis().setUserCheckedOut(user, false);
+                }
+        ));
     }
 
 }

common/src/main/java/net/william278/husksync/user/CommandUser.java

@@ -24,7 +24,7 @@ import net.kyori.adventure.audience.Audience;
 import net.kyori.adventure.text.Component;
 import org.jetbrains.annotations.NotNull;
 
-public interface CommandUser {
+public interface CommandUser  {
 
     @NotNull
     Audience getAudience();

common/src/main/java/net/william278/husksync/user/ConsoleUser.java

@@ -42,4 +42,6 @@ public final class ConsoleUser implements CommandUser {
     public boolean hasPermission(@NotNull String permission) {
         return true;
     }
+
+
 }

common/src/main/java/net/william278/husksync/util/DataDumper.java

@@ -31,6 +31,8 @@ import java.net.HttpURLConnection;
 import java.net.URL;
 import java.net.URLEncoder;
 import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
 import java.time.format.DateTimeFormatter;
 import java.util.Locale;
 import java.util.StringJoiner;
@@ -133,16 +135,13 @@ public class DataDumper {
      */
     @NotNull
     public String toFile() throws IOException {
-        final File filePath = getFilePath();
-
-        // Write the data from #getString to the file using a writer
-        try (final FileWriter writer = new FileWriter(filePath, StandardCharsets.UTF_8, false)) {
-            writer.write(toString());
+        final Path filePath = getFilePath();
+        try (final FileWriter writer = new FileWriter(filePath.toFile(), StandardCharsets.UTF_8, false)) {
+            writer.write(toString()); // Write the data from #getString to the file using a writer
+            return filePath.toString();
         } catch (IOException e) {
             throw new IOException("Failed to write data to file", e);
         }
-
-        return "~/plugins/HuskSync/dumps/" + filePath.getName();
     }
 
     /**
@@ -152,8 +151,8 @@ public class DataDumper {
      * @throws IOException if the prerequisite dumps parent folder could not be created
      */
     @NotNull
-    private File getFilePath() throws IOException {
-        return new File(getDumpsFolder(), getFileName());
+    private Path getFilePath() throws IOException {
+        return getDumpsFolder().resolve(getFileName());
     }
 
     /**
@@ -163,14 +162,12 @@ public class DataDumper {
      * @throws IOException if the folder could not be created
      */
     @NotNull
-    private File getDumpsFolder() throws IOException {
-        final File dumpsFolder = new File(plugin.getDataFolder(), "dumps");
-        if (!dumpsFolder.exists()) {
-            if (!dumpsFolder.mkdirs()) {
-                throw new IOException("Failed to create user data dumps folder");
-            }
+    private Path getDumpsFolder() throws IOException {
+        final Path dumps = plugin.getConfigDirectory().resolve("dumps");
+        if (!Files.exists(dumps)) {
+            Files.createDirectory(dumps);
         }
-        return dumpsFolder;
+        return dumps;
     }
 
     /**

common/src/main/resources/database/postgresql_schema.sql

@@ -15,7 +15,7 @@ CREATE TABLE IF NOT EXISTS "%user_data_table%"
     timestamp    timestamp   NOT NULL,
     save_cause   varchar(32) NOT NULL,
     pinned       boolean     NOT NULL DEFAULT FALSE,
-    data         longblob       NOT NULL,
+    data         bytea       NOT NULL,
 
     PRIMARY KEY (version_uuid, player_uuid),
     FOREIGN KEY (player_uuid) REFERENCES "%users_table%" (uuid) ON DELETE CASCADE

common/src/main/resources/locales/zh-tw.yml

@@ -1,34 +1,34 @@
 locales:
-  synchronization_complete: '[⏵ 資料已同步!](#00fb9a)'
+  synchronization_complete: '[⏵資料已同步!](#00fb9a)'
   synchronization_failed: '[⏵ 無法同步您的資料! 請聯繫管理員](#ff7e5e)'
   inventory_viewer_menu_title: '&0%1% 的背包'
   ender_chest_viewer_menu_title: '&0%1% 的終界箱'
-  inventory_viewer_opened: '[查看備份](#00fb9a) [%1%](#00fb9a bold) [於 ⌚ %2% 的背包備份](#00fb9a)'
-  ender_chest_viewer_opened: '[查看備份](#00fb9a) [%1%](#00fb9a bold) [於 ⌚ %2% 的終界箱備份](#00fb9a)'
-  data_update_complete: '[🔔 你的數據資料已更新!](#00fb9a)'
-  data_update_failed: '[🔔 無法更新你的數據資料! 請聯繫管理員](#ff7e5e)'
-  user_registration_complete: '[⭐ 用戶註冊完成!](#00fb9a)'
-  data_manager_title: '[正在查看玩家](#00fb9a) [%3%](#00fb9a bold show_text=&7玩家UUID:\n&8%4%) [的數據備份](#00fb9a) [%1%](#00fb9a show_text=&7備份版本UUID:\n&8%2%)[:](#00fb9a)'
-  data_manager_timestamp: '[⌚ %1%](#ffc43b-#f5c962 show_text=&7備份時間:\n&8數據保存時間)'
-  data_manager_pinned: '[※ 被標記的備份](#d8ff2b show_text=&7已標記:\n&8此玩家數據備份不會按照備份時間自動排序)'
-  data_manager_cause: '[⚑ %1%](#23a825-#36f539 show_text=&7保存原因:\n&8導致數據保存的原因)'
-  data_manager_server: '[☁ %1%](#ff87b3-#f5538e show_text=&7伺服器:\n&8數據保存所在伺服器的名稱)'
-  data_manager_size: '[⏏ %1%](color=#62a9f5-#7ab8fa show_text=&7備份大小:\n&8備份的估計文件大小(以KiB為單位))\n'
+  inventory_viewer_opened: '[查看](#00fb9a) [%1%](#00fb9a bold) [於 ⌚ %2% 的背包快照資料](#00fb9a)'
+  ender_chest_viewer_opened: '[查看](#00fb9a) [%1%](#00fb9a bold) [於 ⌚ %2% 的終界箱快照資料](#00fb9a)'
+  data_update_complete: '[🔔 你的資料已更新!](#00fb9a)'
+  data_update_failed: '[🔔 無法更新您的資料！ 請聯繫管理員](#ff7e5e)'
+  user_registration_complete: '[⭐ 使用者註冊成功!](#00fb9a)'
+  data_manager_title: '[查看](#00fb9a) [%3%](#00fb9a bold show_text=&7玩家 UUID:\n&8%4%) [的快照:](#00fb9a) [%1%](#00fb9a show_text=&7Version UUID:\n&8%2%) [:](#00fb9a)'
+  data_manager_timestamp: '[⌚ %1%](#ffc43b-#f5c962 show_text=&7快照時間:\n&8資料儲存時間)'
+  data_manager_pinned: '[※ 被標記的快照](#d8ff2b show_text=&7標記:\n&8此快照資料不會自動輪換)'
+  data_manager_cause: '[⚑ %1%](#23a825-#36f539 show_text=&7保存原因:\n&8觸發儲存的原因)'
+  data_manager_server: '[☁ %1%](#ff87b3-#f5538e show_text=&7伺服器:\n&8儲存資料的伺服器名稱)'
+  data_manager_size: '[⏏ %1%](color=#62a9f5-#7ab8fa show_text=&7快照大小:\n&8快照的預估檔案大小（KiB）)\n'
   data_manger_status: '[%1%](red)[/](gray)[%2%](red)[×](gray)[❤](red show_text=&7血量)   [%3%](yellow)[×](gray)[🍖](yellow show_text=&7飽食度)   [ʟᴠ](green)[.](gray)[%4%](green show_text=&7經驗等級)   [🏹 %5%](dark_aqua show_text=&7遊戲模式)'
-  data_manager_advancements_statistics: '[⭐ 成就: %1%](color=#ffc43b-#f5c962 show_text=&7已獲得的成就:\n&8%2%)   [⌛ 遊玩時間: %3%小時](color=#62a9f5-#7ab8fa show_text=&7在遊戲内遊玩的時間\n&8⚠ 基於遊戲内的統計訊息)\n'
+  data_manager_advancements_statistics: '[⭐ 成就: %1%](color=#ffc43b-#f5c962 show_text=&7已獲得的成就:\n&8%2%)   [⌛ 遊戲時間: %3%ʜʀs](color=#62a9f5-#7ab8fa show_text=&7遊戲內的遊玩時間\n&8⚠ 根據遊戲內統計)\n'
   data_manager_item_buttons: '[查看:](gray) [[🪣 背包…]](color=#a17b5f-#f5b98c show_text=&7點擊查看 run_command=/inventory %1% %2%)   [[⌀ 終界箱…]](#b649c4-#d254ff show_text=&7點擊查看 run_command=/enderchest %1% %2%)'
-  data_manager_management_buttons: '[管理:](gray) [[❌ 刪除…]](#ff3300 show_text=&7點擊刪除此玩家數據的備份.\n&8這不會影響玩家的當前數據.\n&#ff3300&⚠ 此操作無法撤銷! suggest_command=/husksync:userdata delete %1% %2%)   [[⏪ 恢復…]](#00fb9a show_text=&7點擊還原此玩家的數據.\n&8這將會讓用户的數據恢復到此備份.\n&#ff3300&⚠ %1%當前的數據將被覆蓋! suggest_command=/husksync:userdata restore %1% %2%)   [[※ 標記/取消標記…]](#d8ff2b show_text=&7點擊標記或取消標記此玩家數據備份\n&8已標記的備份不會按照備份時間自動排序 run_command=/userdata pin %1% %2%)'
-  data_manager_system_buttons: '[系統:](gray) [[⏷ 本地轉存…]](dark_gray show_text=&7點擊將此玩家數據資料轉存到本地文件中.\n&8轉存的資料可以在以下路徑找到~/plugins/HuskSync/dumps/中找到 run_command=/husksync:userdata dump %1% %2% file)   [[☂ 雲端轉存…]](dark_gray show_text=&7點擊將此玩家數據資料轉存到 mc-logs 服務中\n&8您將獲得一個包含資料的URL. run_command=/husksync:userdata dump %1% %2% web)'
-  data_manager_advancements_preview_remaining: '以及其他 %1%…'
-  data_list_title: '[%1%的玩家數據備份:](#00fb9a) [(%2%-%3% of](#00fb9a) [%4%](#00fb9a bold)[)](#00fb9a)\n'
-  data_list_item: '[%1%](gray show_text=&7玩家數據備份 %2%&8⚡ %4% run_command=/userdata view %2% %3%) [%5%](#d8ff2b show_text=&7已標記:\n&8標記的備份不會自動加載 run_command=/userdata view %2% %3%) [%6%](color=#ffc43b-#f5c962 show_text=&7備份時間:&7\n&8數據保存時間\n&8%7% run_command=/userdata view %2% %3%)   [⚑ %8%](#23a825-#36f539 show_text=&7保存原因:\n&8導致數據保存的原因 run_command=/userdata view %2% %3%)   [⏏ %9%](color=#62a9f5-#7ab8fa show_text=&7備份大小:&7\n&8備份的估計文件大小(以KiB為單位) run_command=/userdata view %2% %3%)'
-  data_list_item_invalid: '[%1%](dark_gray show_text=&7User Data Snapshot for %2%\n&8⚡ %4% suggest_command=/userdata delete %2% %3%) [%5%](dark_gray show_text=&7Pinned:\n&8Pinned snapshots won''t be automatically rotated. suggest_command=/userdata delete %2% %3%) [%6%   ⚑ %8%   ⏏ %9%](gray strikethrough show_text=&#ff3300&Invalid Data Snapshot\n&#ff7e5e&Click to delete\n\n&7⚠ %10% suggest_command=/userdata delete %2% %3%)'
-  data_deleted: '[❌ 成功刪除玩家](#00fb9a) [%3%](#00fb9a show_text=&7玩家 UUID:\n&7%4%) [的數據備份](#00fb9a) [%1%.](#00fb9a show_text=&7備份版本UUID:\n&7%2%)'
-  data_restored: '[⏪ 成功恢復玩家](#00fb9a) [%1%](#00fb9a show_text=&7玩家 UUID:\n&7%2%)[的數據備份](#00fb9a) [%3%.](#00fb9a show_text=&7備份版本UUID:\n&7%4%)'
-  data_pinned: '[※ 成功標記玩家](#00fb9a) [%3%](#00fb9a show_text=&7玩家 UUID:\n&8%4%) [的數據備份](#00fb9a) [%1%.](#00fb9a show_text=&7備份版本UUID:\n&8%2%)'
-  data_unpinned: '[※ 成功取消標記玩家](#00fb9a) [%3%](#00fb9a show_text=&7玩家 UUID:\n&8%4%) [的數據備份](#00fb9a) [%1%.](#00fb9a show_text=&7備份版本UUID:\n&8%2%)'
-  data_dumped: '[☂ 已成功將 %1% 的玩家數據快照 %2% 儲存至:](#00fb9a) &7%3%'
-  list_footer: '\n%1%[頁數](#00fb9a) [%2%](#00fb9a)/[%3%](#00fb9a)%4%   %5%'
+  data_manager_management_buttons: '[管理:](gray) [[❌ 刪除…]](#ff3300 show_text=&7點擊刪除這個快照\n&8這不會影像目前玩家的資料\n&#ff3300&⚠ 此操作不能取消! suggest_command=/husksync:userdata delete %1% %2%)   [[⏪ 恢復…]](#00fb9a show_text=&7點擊將玩家資料覆蓋為此快照\n&8這將導致玩家的資料會被此快照覆蓋\n&#ff3300&⚠ %1% 當前的資料將被覆蓋! suggest_command=/husksync:userdata restore %1% %2%)   [[※ 標記…]](#d8ff2b show_text=&7點擊切換標記狀態\n&8被標記的快照將不會自動輪換更新 run_command=/userdata pin %1% %2%)'
+  data_manager_system_buttons: '[系統:](gray) [[⏷ 本地轉存…]](dark_gray show_text=&7點擊將此玩家資料快照轉存到本地文件中\n&8轉存的資料可以在以下路徑找到 ~/plugins/HuskSync/dumps/ run_command=/husksync:userdata dump %1% %2% file)   [[☂ 雲端轉存…]](dark_gray show_text=&7點擊將此玩家資料快照轉存到 mc-logs 服務\n&8您將獲得一個包含資料的 URL. run_command=/husksync:userdata dump %1% %2% web)'
+  data_manager_advancements_preview_remaining: '還有 %1% …'
+  data_list_title: '[%1% 的玩家資料快照:](#00fb9a) [(%2%-%3% 共](#00fb9a) [%4%](#00fb9a bold)[)](#00fb9a)\n'
+  data_list_item: '[%1%](gray show_text=&7玩家資料快照 %2%\n&8⚡ %4% run_command=/userdata view %2% %3%) [%5%](#d8ff2b show_text=&7已標記:\n&8標記的快照將不會自動輪換。 run_command=/userdata view %2% %3%) [%6%](color=#ffc43b-#f5c962 show_text=&7版本時間戳:\n&8資料儲存時間\n&8%7% run_command=/userdata view %2% %3%) [⚑ %8%](#23a825-#36f539 show_text=&7儲存原因:\n&8觸發儲存的原因 run_command=/userdata view %2% %3%) [⏏ %9%](color=#62a9f5-#7ab8fa show_text=&7快照大小:\n&8快照的預估檔案大小（KiB） run_command=/userdata view %2% %3%)'
+  data_list_item_invalid: '[%1%](dark_gray show_text=&7玩家資料快照 %2%\n&8⚡ %4% suggest_command=/userdata delete %2% %3%) [%5%](dark_gray show_text=&7已標記:\n&8標記的快照將不會自動輪換。 suggest_command=/userdata delete %2% %3%) [%6% ⚑ %8% ⏏ %9%](gray strikethrough show_text=&#ff3300&無效的資料快照\n&#ff7e5e&點擊刪除\n\n&7⚠ %10% suggest_command=/userdata delete %2% %3%)'
+  data_deleted: '[❌ 成功刪除:](#00fb9a) [%3%](#00fb9a show_text=&7玩家 UUID:\n&8%4%) [的快照:](#00fb9a) [%1%](#00fb9a show_text=&7Version UUID:\n&8%2%)'
+  data_restored: '[⏪ 成功將玩家](#00fb9a) [%1%](#00fb9a show_text=&7玩家 UUID:\n&8%2%)[的資料恢復為 快照:](#00fb9a) [%3%.](#00fb9a show_text=&7Version UUID:\n&8%4%)'
+  data_pinned: '[※ 成功標記](#00fb9a) [%3%](#00fb9a show_text=&7玩家 UUID:\n&8%4%) [的快照:](#00fb9a) [%1%](#00fb9a show_text=&7Version UUID:\n&8%2%)'
+  data_unpinned: '[※ 成功解除](#00fb9a) [%3%](#00fb9a show_text=&7玩家 UUID:\n&8%4%) [快照:](#00fb9a) [%1%](#00fb9a show_text=&7Version UUID:\n&8%2%) [的標記](#00fb9a)'
+  data_dumped: '[☂ 成功將 %2% 資料快照 %1% 儲存至:](#00fb9a) &7%3%'
+  list_footer: '\n%1%[頁面](#00fb9a) [%2%](#00fb9a)/[%3%](#00fb9a)%4%   %5%'
   list_previous_page_button: '[◀](white show_text=&7查看上一頁 run_command=%2% %1%) '
   list_next_page_button: ' [▶](white show_text=&7查看下一頁 run_command=%2% %1%)'
   list_page_jumpers: '(%1%)'
@@ -36,30 +36,30 @@ locales:
   list_page_jumper_current_page: '[%1%](#00fb9a)'
   list_page_jumper_separator: ' '
   list_page_jumper_group_separator: '…'
-  save_cause_disconnect: '斷開連接'
-  save_cause_world_save: '保存世界'
+  save_cause_disconnect: '離線'
+  save_cause_world_save: '世界儲存'
   save_cause_death: '死亡'
   save_cause_server_shutdown: '伺服器關閉'
   save_cause_inventory_command: '背包指令'
   save_cause_enderchest_command: '終界箱指令'
   save_cause_backup_restore: '備份還原'
   save_cause_api: 'API'
-  save_cause_mpdb_migration: 'MPDB遷移'
+  save_cause_mpdb_migration: 'MPDB 遷移'
   save_cause_legacy_migration: '舊版遷移'
-  save_cause_converted_from_v2: '從v2轉換'
-  up_to_date: '[HuskSync](#00fb9a bold) [| 您運行的是最新版本的HuskSync(v%1%).](#00fb9a)'
-  update_available: '[HuskSync](#ff7e5e bold) [| 發現可用的新版本:v%1%(當前版本:v%2%).](#ff7e5e)'
-  reload_complete: '[HuskSync](#00fb9a bold) [| 已重新載入配置和訊息文件.](#00fb9a)\n[⚠ 確保所有伺服器上的配置文件都是最新的!](#00fb9a)\n[需要重新啟動配置更改才能生效.](#00fb9a italic)'
+  save_cause_converted_from_v2: '從 v2 轉換'
+  up_to_date: '[HuskSync](#00fb9a bold) [| 您運行的是最新版本的 HuskSync (v%1%).](#00fb9a)'
+  update_available: '[HuskSync](#ff7e5e bold) [| 發現可用的新版本: v%1% (running: v%2%).](#ff7e5e)'
+  reload_complete: '[HuskSync](#00fb9a bold) [| 配置和語言文件已重新加載。](#00fb9a)\n[⚠ 確保所有伺服器上的配置文件都是最新的！](#00fb9a)\n[重啟後配置變更才會生效。](#00fb9a italic)'
   system_status_header: '[HuskSync](#00fb9a bold) [| 系統狀態報告:](#00fb9a)'
   error_invalid_syntax: '[錯誤:](#ff3300) [語法不正確，用法:](#ff7e5e) [%1%](#ff7e5e italic show_text=&#ff7e5e&點擊建議 suggest_command=%1%)'
-  error_invalid_player: '[錯誤:](#ff3300) [找不到這位玩家.](#ff7e5e)'
-  error_invalid_data: '[Error:](#ff3300) [Failed to unpack user data as the snapshot is invalid or corrupt.](#ff7e5e) [(Details…)](gray show_text=&7⚠ %1%)'
+  error_invalid_player: '[錯誤:](#ff3300) [找不到這位玩家](#ff7e5e)'
+  error_invalid_data: '[錯誤:](#ff3300) [無法解壓使用者資料，因為快照無效或已損壞。](#ff7e5e) [(詳細資訊…)](gray show_text=&7⚠ %1%)'
   error_no_permission: '[錯誤:](#ff3300) [您沒有權限執行這個指令](#ff7e5e)'
   error_console_command_only: '[錯誤:](#ff3300) [該指令只能透過 控制台 執行](#ff7e5e)'
-  error_in_game_command_only: '錯誤: 該指令只能在遊戲內執行.'
-  error_no_data_to_display: '[錯誤:](#ff3300) [找不到任何可顯示的玩家數據.](#ff7e5e)'
-  error_invalid_version_uuid: '[錯誤:](#ff3300) [找不到該版本UUID的任何玩家數據.](#ff7e5e)'
-  husksync_command_description: '管理HuskSync插件'
-  userdata_command_description: '查看、管理和恢復玩家用户數據'
-  inventory_command_description: '查看和編輯玩家的背包'
+  error_in_game_command_only: '[錯誤:](#ff3300) [該指令只能在遊戲內執行](#ff7e5e)'
+  error_no_data_to_display: '[錯誤:](#ff3300) [找不到任何可顯示的用戶資料.](#ff7e5e)'
+  error_invalid_version_uuid: '[錯誤:](#ff3300) [找不到正確的 Version UUID.](#ff7e5e)'
+  husksync_command_description: '管理 HuskSync 插件'
+  userdata_command_description: '查看、管理和還原玩家資料'
+  inventory_command_description: '查看和編輯玩家的物品欄'
   enderchest_command_description: '查看和編輯玩家的終界箱'

docs/API-Events.md

@@ -4,11 +4,20 @@ Consult the Javadocs for more information. Please note that carrying out expensi
 
 ## Bukkit Platform Events
 > **Tip:** Don't forget to register your listener when listening for these event calls.
-> 
+ 
 | Bukkit Event class        | Cancellable | Description                                                                                 |
 |---------------------------|:-----------:|---------------------------------------------------------------------------------------------|
 | `BukkitDataSaveEvent`     |      ✅      | Called when player data snapshot is created, saved and cached due to a DataSaveCause        |
 | `BukkitPreSyncEvent`      |      ✅      | Called before a player has their data updated from the cache or database, just after login  |
 | `BukkitSyncCompleteEvent` |      ❌      | Called once a player has completed their data synchronization on login successfully† |
 
+## Fabric Platform Callbacks
+> Access the callback via the static EVENT field in each interface class.
+
+| Fabric Callback              | Cancellable | Description                                                                                 |
+|------------------------------|:-----------:|---------------------------------------------------------------------------------------------|
+| `FabricDataSaveCallback`     |      ✅      | Called when player data snapshot is created, saved and cached due to a DataSaveCause        |
+| `FabricPreSyncCallback`      |      ✅      | Called before a player has their data updated from the cache or database, just after login  |
+| `FabricSyncCompleteCallback` |      ❌      | Called once a player has completed their data synchronization on login successfully† |
+
 †This can also fire when a user's data is updated while the player is logged in; i.e., when an admin rolls back the user, updates their inventory or Ender Chest through the respective commands, or when an API call is made forcing the user to have their data updated.

docs/API.md

@@ -17,6 +17,7 @@ The HuskSync API shares version numbering with the plugin itself for consistency
 The HuskSync API is available for the following platforms:
 
 * `bukkit` - Bukkit, Spigot, Paper, etc. Provides Bukkit API event listeners and adapters to `org.bukkit` objects.
+* `fabric` - Fabric API for Minecraft. Provides Fabric API event listeners and adapters to `net.minecraft` objects.
 * `common` - Common API for all platforms.
 
 
@@ -52,7 +53,7 @@ Add the repository to your `pom.xml` as per below. You can alternatively specify
     </repository>
 </repositories>
 ```
-Add the dependency to your `pom.xml` as per below. Replace `VERSION` with the latest version of HuskSync (without the v): ![Latest version](https://img.shields.io/github/v/tag/WiIIiam278/HuskSync?color=%23282828&label=%20&style=flat-square)
+Add the dependency to your `pom.xml` as per below. Replace `VERSION` with the latest version of HuskSync (without the v): ![Latest version](https://img.shields.io/github/v/tag/WiIIiam278/HuskSync?color=%23282828&label=%20&style=flat-square). Note for Fabric you must append the target Minecraft version to the version number (e.g. `3.6.1+1.20.1`).
 ```xml
 <dependency>
     <groupId>net.william278.husksync</groupId>
@@ -75,7 +76,7 @@ allprojects {
 	}
 }
 ```
-Add the dependency as per below. Replace `VERSION` with the latest version of HuskSync (without the v): ![Latest version](https://img.shields.io/github/v/tag/WiIIiam278/HuskSync?color=%23282828&label=%20&style=flat-square)
+Add the dependency as per below. Replace `VERSION` with the latest version of HuskSync (without the v): ![Latest version](https://img.shields.io/github/v/tag/WiIIiam278/HuskSync?color=%23282828&label=%20&style=flat-square). Note for Fabric you must append the target Minecraft version to the version number (e.g. `3.6.1+1.20.1`).
 
 ```groovy
 dependencies {

docs/Config-File.md

@@ -28,13 +28,13 @@ check_for_updates: true
 cluster_id: ''
 # Enable development debug logging
 debug_logging: true
-# Whether to provide modern, rich TAB suggestions for commands (if available)
-brigadier_tab_completion: false
 # Whether to enable the Player Analytics hook.
 # Docs: https://william278.net/docs/husksync/plan-hook
 enable_plan_hook: true
-# Whether to cancel game event packets directly when handling locked players if ProtocolLib is installed
+# Whether to cancel game event packets directly when handling locked players if ProtocolLib or PacketEvents is installed
 cancel_packets: true
+# Add HuskSync commands to this list to prevent them from being registered (e.g. ['userdata'])
+disabled_commands: []
 # Database settings
 database:
   # Type of database to use (MYSQL, MARIADB, POSTGRES, MONGO)
@@ -78,7 +78,7 @@ redis:
     # List of host:port pairs
     nodes: []
     password: ''
-# Redis settings
+# Data syncing settings
 synchronization:
   # The data synchronization mode to use (LOCKSTEP or DELAY). LOCKSTEP is recommended for most networks.
   # Docs: https://william278.net/docs/husksync/sync-modes

docs/Custom-Data-API.md

@@ -93,7 +93,7 @@ public class LoginParticleData extends BukkitData implements Adaptable {
 public class LoginParticleSerializer extends BukkitSerializer.Json<LoginParticleData> implements Serializer<LoginParticleData> {
     
     // We need to create a constructor that takes our instance of the API
-    public GameMode(@NotNull HuskSyncAPI api) {
+    public LoginParticleSerializer(@NotNull HuskSyncAPI api) {
         super(api, LoginParticleData.class); // We pass the class type here so that Gson knows what class we're serializing
     }
 
@@ -116,12 +116,26 @@ public static Identifier LOGIN_PARTICLES_ID = Identifier.from("myplugin", "login
 huskSyncAPI.registerSerializer(LOGIN_PARTICLES_ID, new LoginParticleSerializer(HuskSyncAPI.getInstance()));
 ```
 
+### 3.1 Identifier dependencies
+* HuskSync lets you specify a set of `Dependency` objects when creating an `Identifier`. These are used to deterministically apply data in a specific order.
+* Dependencies are references to other data type identifiers. HuskSync will apply data in dependency-order; that is, it will apply the data of the dependencies before applying the data of the dependent.
+* This is useful when you have data that relies on other data to be applied first; for example, if you're writing an add-on for additional modded inventory data and you need to apply the base inventory data first.
+* You can specify whether a dependency is required or optional. HuskSync will not sync data of a type that has a required dependency that is missing (for instance, if it is disabled in the config, or - if provided by another plugin - has failed to register).
+* Use `Identifer#from(String, String, Set<Dependency>)` or `Identifier#from(Key, Set<Dependency>)` to create an identifier with dependencies
+* Dependencies can be created with `Dependency.optional(Identifier)` or `Dependency.required(Identifier)` for optional or required dependencies respectively.
+
 ## 4. Setting and getting our Data to/from a User
 * Now that we've registered our `Data` and `Serializer` classes, we can set our data to a user, applying it to them.
 * To do this, we use the `OnlineUser#setData(Identifier, Data)` method.
   * This method will apply the data to the user, and store the data to the plugin player custom data map, to allow the data to be retrieved later and be saved to snapshots.
 * Snapshots created on servers where the data type is registered will now contain our data and synchronise between instances!
 
+```java
+// Create an identifier for our data requiring the user's location to have been set first
+public static Identifier LOGIN_PARTICLES_ID = Identifier.from("myplugin", "login_particles", Set.of(Dependency.optional(Key.key("husksync", "location"))));
+// We can then register this as we did previously (...)
+```
+
 ```java
 // Create an instance of our data
 LoginParticleData loginParticleData = new LoginParticleData("FIREWORKS_SPARK", 10);
@@ -134,7 +148,7 @@ LoginParticleData loginParticleData = (LoginParticleData) huskSyncAPI.getUser(pl
 ```
 
 ### 4.1 Persisting custom data on the DataSaveEvent
-Add an EventListener to the `DataSaveEvent` and use the `#editData` consumer method to apply custom data during standard DataSaves. This will persist data to users any time the data save routine executes (on user logout, server shutdownm, world save, etc).
+Add an EventListener to the `DataSaveEvent` and use the `#editData` consumer method to apply custom data during standard DataSaves. This will persist data to users any time the data save routine executes (on user logout, server shutdown, world save, etc.)
 
 ```java
 @EventHandler

docs/Data-Snapshot-API.md

@@ -213,8 +213,8 @@ huskSyncAPI.getCurrentData(user).thenAccept(optionalSnapshot -> {
     // Get the health data
     Data.Health health = healthOptional.get();
     double currentHealth = health.getCurrentHealth(); // Current health
-    double healthScale = health.getHealthScale(); // Health scale (e.g., 20 for 20 hearts)
-    snapshot.setHealth(BukkitData.Health.from(20, 20));
+    double healthScale = health.getHealthScale(); // Health scale (used to determine health/damage display hearts)
+    snapshot.setHealth(BukkitData.Health.from(20, 20, true));
     // Need max health? Look at the Attributes data type.
     
     // Get the game mode data

docs/FAQs.md

@@ -12,23 +12,29 @@ HuskSync supports synchronising a wide range of different data elements, each of
 <details>
 <summary>&nbsp;<b>Are modded items supported?</b></summary>
 
-If you're running HuskSync on Arclight or similar, please note we will not be able to provide you with support, but have been reported to save & sync correctly with HuskSync v3.x+.
+On Fabric, modded items should usually sync as you would expect with HuskSync. Note that mods which store additional data separate from item NBT on each server may not work as expected. Mod developers &mdash; check out the [[Custom Data API]] for information on how to get your mod's data syncing!
 
-**TL;DR** &mdash; modded items may work, but since we can't guarantee compatibility, we do not officially mark them as supported. Be sure to test thoroughly before deploying on production!
+On Spigot, if you're running HuskSync on Arclight or similar, please note we will not be able to provide you with support, but have been reported to save & sync correctly with HuskSync v3.x+.
+
+Please note we cannot guarantee compatibility with everything &mdash; test thoroughly!
 
 </details>
 
 <details>
 <summary>&nbsp;<b>Are MMOItems / SlimeFun / ItemsAdder items supported?</b></summary>
 
-These plugins, which provide custom items, should be supported as of HuskSync v3.x+; but do note we cannot guarantee compatibility with all methods of injecting custom data to create custom items. Be sure to test thoroughly before deploying on production!
+These custom item Spigot plugins should work as expected provided they inject data into item NBT in a standard way.
+
+Please note we cannot guarantee compatibility with everything &mdash; test thoroughly!
 
 </details>
 
 <details>
 <summary>&nbsp;<b>Is Redis required? What is Redis?</b></summary>
 
-HuskSync requires Redis to operate (for reasons demonstrated below). Redis is an in-memory database server used for caching data at scale and sending messages across a network. You have a Redis server in a similar fashion to the way you have a MySQL database server. If you're using a Minecraft hosting company, you'll want to contact their support and ask if they offer Redis. If you're looking for a host, I have a list of some popular hosts and whether they support Redis [available to read here.](https://william278.net/redis-hosts)
+Yes! HuskSync requires Redis to operate (for reasons demonstrated below).
+
+Redis is an in-memory database server used for caching data at scale and sending messages across a network. You have a Redis server in a similar fashion to the way you have a MySQL database server. If you're using a Minecraft hosting company, you'll want to contact their support and ask if they offer Redis. If you're looking for a host, I have a list of some popular hosts and whether they support Redis [available to read here.](https://william278.net/redis-hosts)
 
 </details>
 

docs/Home.md

@@ -30,5 +30,5 @@ Welcome! This is the plugin documentation for HuskSync v3.x+. Please click throu
 * 📂 [Buy HuskSync](https://william278.net/project/husksync/)
   * 🚰 [Spigot](https://www.spigotmc.org/resources/husksync.97144/)
   * 🛒 [Polymart](https://polymart.org/resource/husksync.1634)
-  * ⚒️ [Craftaro](https://craftaro.com/marketplace/product/husksync.758)
+  * ⚒️ [BuiltByBit](https://craftaro.com/marketplace/product/husksync.758)
 * 💬 [Discord Support](https://discord.gg/tVYhJfyDWG)

docs/Setup.md

@@ -1,50 +1,63 @@
-This will walk you through installing HuskSync on your network of Spigot servers.
+> **Warning:** Fabric support is currently in beta and is not production ready yet. Customers can get in touch on Discord to request the Fabric build, or you can self-compile.
+
+This will walk you through installing HuskSync on your network of Spigot or Fabric servers.
 
 ## Requirements
-> **Note:** If the plugin fails to load, please check that you are not running an [incompatible version combination](Unsupported-Versions)
+> **Warning:** Mixing and matching Fabric/Spigot servers is not supported, and all servers must be running the same Minecraft version.
 
-* A MySQL Database (v8.0+) (MariaDB, PostrgreSQL or MongoDB are also supported)
+> **Note:** Please also note some specific legacy Paper/Purpur versions are [not compatible](Unsupported-Versions) with HuskSync.
+
+* A MySQL Database (v8.0+)
+  * **OR** a MariaDB, PostrgreSQL or MongoDB database, which are also supported
 * A Redis Database (v5.0+) — see [[FAQs]] for more details.
 * Any number of Spigot servers, connected by a BungeeCord or Velocity-based proxy (Minecraft v1.17.1+, running Java 17+)
+  * **OR** a network of Fabric servers, connected by a Fabric proxy (Minecraft v1.20.1, running Java 17+)
 
 ## Setup Instructions
 ### 1. Install the jar
-- Place the plugin jar file in the `/plugins/` directory of each Spigot server.
+- Place the plugin jar file in the `/plugins/` or `/mods/` directory of each Spigot/Fabric server respectively.
 - You do not need to install HuskSync as a proxy plugin.
-- You can additionally install [ProtocolLib](https://www.spigotmc.org/resources/protocollib.1997/) for better locked user handling, and [Plan](https://www.spigotmc.org/resources/plan-player-analytics.32536/) for analytics.
+- _Spigot users_: You can additionally install [ProtocolLib](https://www.spigotmc.org/resources/protocollib.1997/) or [PacketEvents](https://www.spigotmc.org/resources/packetevents-api.80279/) for better locked user handling.
+- _Fabric users_: Ensure the latest Fabric API mod jar is installed! 
 
 ### 2. Restart servers
 - Start, then stop every server to let HuskSync generate the [[config file]].
 - HuskSync will throw an error in the console and disable itself as it is unable to connect to the database. You haven't set the credentials yet, so this is expected.
-- Advanced users: If you'd prefer, you can create one config.yml file and create symbolic links in each `/plugins/HuskSync/` folder to it to make updating it easier.
 
 ### 3. Enter Mysql & Redis database credentials
-- Navigate to the HuskSync config file on each server (`~/plugins/HuskSync/config.yml`)
+- Navigate to the new config file on each server (`~/plugins/HuskSync/config.yml` on Spigot, `~/config/husksync/config.yml` on Fabric)
 - Under `credentials` in the `database` section, enter the credentials of your (MySQL/MariaDB/MongoDB/PostgreSQL) Database. You shouldn't touch the `connection_pool` properties.
 - Under `credentials` in the `redis` section, enter the credentials of your Redis Database. If your Redis server doesn't have a password, leave the password blank as it is.
 - Unless you want to have multiple clusters of servers within your network, each with separate user data, you should not change the value of `cluster_id`.
 
 <details>
-<summary>Important &mdash; MongoDB Users</summary>
+<summary>MongoDB users &mdash; additional instructions</summary>
 
 - Navigate to the HuskSync config file on each server (`~/plugins/HuskSync/config.yml`)
 - Set `type` in the `database` section to `MONGO`
 - Under `credentials` in the `database` section, enter the credentials of your MongoDB Database. You shouldn't touch the `connection_pool` properties.
-<details>
+- Under `parameters` in the `mongo_settings` section, ensure the specified `&authSource=` matches the database you are using (default is `HuskSync`).
 
-<summary>Additional configuration for MongoDB Atlas users</summary>
+#### Additional setup for MongoDB Atlas
 
-- Navigate to the HuskSync config file on each server (`~/plugins/HuskSync/config.yml`)
 - Set `using_atlas` in the `mongo_settings` section to `true`. 
 - Remove `&authSource=HuskSync` from `parameters` in the `mongo_settings`. 
 
 (The `port` setting in `credentials` is disregarded when using Atlas.)
 </details>
 
+<details>
+<summary>Pterodactyl self-hosts &mdash; Redis setup instructions</summary>
+
+If you are hosting your Redis server on the same node as your servers, you need to use `172.18.0.1` as your host (or equivalent if you changed your network settings), and bind it in the Redis config `nano /etc/redis/redis.conf`.
+
+You will also need to uncomment the `requirepass` directive and set a password to allow outside connections, or disable `protected-mode`. Once a password is set and Redis is restarted `systemctl restart redis`, you will also need to update the password in your pterodactyl `.env` (`nano /var/www/pterodactyl/.env`) and refresh the cache `cd /var/www/pterodactyl && php artisan config:clear`.
+
+You may also need to allow connections from your firewall depending on your distribution.
 </details>
 
 ### 4. Set server names in server.yml files
-- Navigate to the HuskSync server name file on each server (`~/plugins/HuskSync/server.yml`)
+- Navigate to the server name file on each server (`~/plugins/HuskSync/server.yml` on Spigot, `~/config/husksync/server.yml` on Fabric)
 - Set the `name:` of the server in this file to the ID of this server as defined in the config of your proxy (e.g., if this is the "hub" server you access with `/server hub`, put `'hub'` here)
 
 ### 5. Start every server again

docs/Sync-Features.md

@@ -38,7 +38,7 @@ Although it's a common request, HuskSync doesn't synchronize economy data for a
 I strongly recommend making use of economy plugins that have cross-server economy balance synchronization built-in, of which there are a multitude of options available. Please see our [[FAQs]] section for more details on this decision.
 
 ## Toggling Sync Features
-All synchronization features, except location and locked map synchronising, are enabled by default. To toggle a feature, navigate to the `features:` section in the `synchronization:` part of your `config.yml` file, and change the option to `true`/`false` respectively.
+All synchronization features, except location and locked map synchronizing, are enabled by default. To toggle a feature, navigate to the `features:` section in the `synchronization:` part of your `config.yml` file, and change the option to `true`/`false` respectively.
 
 <details>
 <summary>Example in config.yml</summary>

docs/_Sidebar.md

@@ -27,6 +27,5 @@
 * 📂 [Buy HuskSync](https://william278.net/project/husksync/)
   * 🚰 [Spigot](https://www.spigotmc.org/resources/husksync.97144/)
   * 🛒 [Polymart](https://polymart.org/resource/husksync.1634)
-  * ⚒️ [Craftaro](https://craftaro.com/marketplace/product/husksync.758)
-  * 🛒 [BuiltByBit](https://craftaro.com/marketplace/product/husksync.758)
+  * ⚒️ [BuiltByBit](https://craftaro.com/marketplace/product/husksync.758)
 * 💬 [Discord Support](https://discord.gg/tVYhJfyDWG)

fabric/build.gradle

@@ -0,0 +1,72 @@
+plugins {
+    id 'fabric-loom' version '1.7-SNAPSHOT'
+}
+
+apply plugin: 'fabric-loom'
+loom.serverOnlyMinecraftJar()
+
+repositories {
+    maven { url 'https://s01.oss.sonatype.org/content/repositories/snapshots/' }
+    maven { url 'https://maven.nucleoid.xyz' }
+}
+
+dependencies {
+    minecraft "com.mojang:minecraft:${fabric_minecraft_version}"
+    mappings "net.fabricmc:yarn:${fabric_yarn_mappings}:v2"
+    modImplementation "net.fabricmc:fabric-loader:${fabric_loader_version}"
+
+    modImplementation include("net.kyori:adventure-platform-fabric:${adventure_platform_fabric_version}")
+    modImplementation include("me.lucko:fabric-permissions-api:${fabric_permissions_api_version}")
+    modImplementation include("eu.pb4:sgui:${sgui_version}")
+    modImplementation include('net.william278.uniform:uniform-fabric:1.1.8+1.20.1')
+    modCompileOnly "net.fabricmc.fabric-api:fabric-api:${fabric_api_version}"
+
+    implementation include('org.apache.commons:commons-pool2:2.12.0')
+    implementation include("redis.clients:jedis:$jedis_version")
+    implementation include("com.mysql:mysql-connector-j:$mysql_driver_version")
+    implementation include("org.mariadb.jdbc:mariadb-java-client:$mariadb_driver_version")
+    implementation include("org.xerial.snappy:snappy-java:$snappy_version")
+
+    compileOnly 'org.jetbrains:annotations:24.1.0'
+    compileOnly 'net.william278:DesertWell:2.0.4'
+    compileOnly 'org.projectlombok:lombok:1.18.32'
+
+    annotationProcessor 'org.projectlombok:lombok:1.18.32'
+
+    shadow project(path: ":common")
+}
+
+shadowJar {
+    configurations = [project.configurations.shadow]
+    destinationDirectory.set(file("$projectDir/build/libs"))
+
+    exclude('net.fabricmc:.*')
+    exclude('net.kyori:.*')
+    exclude '/mappings/*'
+
+    relocate 'org.apache.commons.io', 'net.william278.husksync.libraries.commons.io'
+    relocate 'org.apache.commons.text', 'net.william278.husksync.libraries.commons.text'
+    relocate 'org.apache.commons.lang3', 'net.william278.husksync.libraries.commons.lang3'
+    relocate 'com.google.gson', 'net.william278.husksync.libraries.gson'
+    relocate 'com.fatboyindustrial', 'net.william278.husksync.libraries'
+    relocate 'de.themoep', 'net.william278.husksync.libraries'
+    relocate 'org.jetbrains', 'net.william278.husksync.libraries'
+    relocate 'org.intellij', 'net.william278.husksync.libraries'
+    relocate 'com.zaxxer', 'net.william278.husksync.libraries'
+    relocate 'de.exlll', 'net.william278.husksync.libraries'
+    relocate 'net.william278.desertwell', 'net.william278.husksync.libraries.desertwell'
+    relocate 'net.william278.paginedown', 'net.william278.husksync.libraries.paginedown'
+    relocate 'org.json', 'net.william278.husksync.libraries.json'
+}
+
+remapJar {
+    dependsOn tasks.shadowJar
+    mustRunAfter tasks.shadowJar
+    inputFile = shadowJar.archiveFile.get()
+    addNestedDependencies = true
+
+    destinationDirectory.set(file("$rootDir/target/"))
+    archiveClassifier.set('')
+}
+
+shadowJar.finalizedBy(remapJar)

fabric/src/main/java/net/william278/husksync/FabricHuskSync.java

@@ -0,0 +1,342 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync;
+
+import com.google.common.collect.Lists;
+import com.google.common.collect.Maps;
+import com.google.common.collect.Sets;
+import com.google.gson.Gson;
+import lombok.AccessLevel;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import net.fabricmc.api.DedicatedServerModInitializer;
+import net.fabricmc.fabric.api.event.lifecycle.v1.ServerLifecycleEvents;
+import net.fabricmc.loader.api.FabricLoader;
+import net.fabricmc.loader.api.ModContainer;
+import net.kyori.adventure.platform.AudienceProvider;
+import net.kyori.adventure.platform.fabric.FabricServerAudiences;
+import net.minecraft.server.MinecraftServer;
+import net.william278.desertwell.util.Version;
+import net.william278.husksync.adapter.DataAdapter;
+import net.william278.husksync.adapter.GsonAdapter;
+import net.william278.husksync.adapter.SnappyGsonAdapter;
+import net.william278.husksync.api.FabricHuskSyncAPI;
+import net.william278.husksync.command.PluginCommand;
+import net.william278.husksync.config.Locales;
+import net.william278.husksync.config.Server;
+import net.william278.husksync.config.Settings;
+import net.william278.husksync.data.*;
+import net.william278.husksync.database.Database;
+import net.william278.husksync.database.MongoDbDatabase;
+import net.william278.husksync.database.MySqlDatabase;
+import net.william278.husksync.database.PostgresDatabase;
+import net.william278.husksync.event.FabricEventDispatcher;
+import net.william278.husksync.hook.PlanHook;
+import net.william278.husksync.listener.EventListener;
+import net.william278.husksync.listener.FabricEventListener;
+import net.william278.husksync.migrator.Migrator;
+import net.william278.husksync.redis.RedisManager;
+import net.william278.husksync.sync.DataSyncer;
+import net.william278.husksync.user.ConsoleUser;
+import net.william278.husksync.user.FabricUser;
+import net.william278.husksync.user.OnlineUser;
+import net.william278.husksync.util.FabricTask;
+import net.william278.husksync.util.LegacyConverter;
+import net.william278.uniform.Uniform;
+import net.william278.uniform.fabric.FabricUniform;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.slf4j.spi.LoggingEventBuilder;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.*;
+import java.util.logging.Level;
+
+@Getter
+@NoArgsConstructor
+public class FabricHuskSync implements DedicatedServerModInitializer, HuskSync, FabricTask.Supplier,
+    FabricEventDispatcher {
+
+    private static final String PLATFORM_TYPE_ID = "fabric";
+
+    private final TreeMap<Identifier, Serializer<? extends Data>> serializers = Maps.newTreeMap(
+        SerializerRegistry.DEPENDENCY_ORDER_COMPARATOR
+    );
+    private final Map<UUID, Map<Identifier, Data>> playerCustomDataStore = Maps.newConcurrentMap();
+    private final Map<String, Boolean> permissions = Maps.newHashMap();
+    private final List<Migrator> availableMigrators = Lists.newArrayList();
+    private final Set<UUID> lockedPlayers = Sets.newConcurrentHashSet();
+    private final Map<UUID, FabricUser> playerMap = Maps.newConcurrentMap();
+
+    private Logger logger;
+    private ModContainer mod;
+    private MinecraftServer minecraftServer;
+    private boolean disabling;
+    private Gson gson;
+    private AudienceProvider audiences;
+    private Database database;
+    private RedisManager redisManager;
+    private EventListener eventListener;
+    private DataAdapter dataAdapter;
+    @Setter
+    private DataSyncer dataSyncer;
+    @Setter
+    private Settings settings;
+    @Setter
+    private Locales locales;
+    @Setter
+    @Getter(AccessLevel.NONE)
+    private Server serverName;
+
+    @Override
+    public void onInitializeServer() {
+        // Get the logger and mod container
+        this.logger = LoggerFactory.getLogger("HuskSync");
+        this.mod = FabricLoader.getInstance().getModContainer("husksync").orElseThrow();
+        this.disabling = false;
+        this.gson = createGson();
+
+        // Load settings and locales
+        initialize("plugin config & locale files", (plugin) -> {
+            loadSettings();
+            loadLocales();
+            loadServer();
+        });
+
+        // Register commands
+        initialize("commands", (plugin) -> getUniform().register(PluginCommand.Type.create(this)));
+
+        // Load HuskSync after server startup
+        ServerLifecycleEvents.SERVER_STARTED.register(server -> {
+            this.minecraftServer = server;
+            this.onEnable();
+        });
+
+        // Unload HuskSync before server shutdown
+        ServerLifecycleEvents.SERVER_STOPPING.register(server -> this.onDisable());
+    }
+
+    private void onEnable() {
+        // Initial plugin setup
+        this.audiences = FabricServerAudiences.of(minecraftServer);
+
+        // Prepare data adapter
+        initialize("data adapter", (plugin) -> {
+            if (getSettings().getSynchronization().isCompressData()) {
+                this.dataAdapter = new SnappyGsonAdapter(this);
+            } else {
+                this.dataAdapter = new GsonAdapter(this);
+            }
+        });
+
+        initialize("data serializers", (plugin) -> {
+            // PERSISTENT_DATA is not registered / available on the Fabric platform
+            registerSerializer(Identifier.INVENTORY, new FabricSerializer.Inventory(this));
+            registerSerializer(Identifier.ENDER_CHEST, new FabricSerializer.EnderChest(this));
+            registerSerializer(Identifier.ADVANCEMENTS, new FabricSerializer.Advancements(this));
+            registerSerializer(Identifier.STATISTICS, new Serializer.Json<>(this, FabricData.Statistics.class));
+            registerSerializer(Identifier.POTION_EFFECTS, new FabricSerializer.PotionEffects(this));
+            registerSerializer(Identifier.GAME_MODE, new Serializer.Json<>(this, FabricData.GameMode.class));
+            registerSerializer(Identifier.FLIGHT_STATUS, new Serializer.Json<>(this, FabricData.FlightStatus.class));
+            registerSerializer(Identifier.ATTRIBUTES, new Serializer.Json<>(this, FabricData.Attributes.class));
+            registerSerializer(Identifier.HEALTH, new Serializer.Json<>(this, FabricData.Health.class));
+            registerSerializer(Identifier.HUNGER, new Serializer.Json<>(this, FabricData.Hunger.class));
+            registerSerializer(Identifier.EXPERIENCE, new Serializer.Json<>(this, FabricData.Experience.class));
+            registerSerializer(Identifier.LOCATION, new Serializer.Json<>(this, FabricData.Location.class));
+            validateDependencies();
+        });
+
+        // Initialize the database
+        initialize(getSettings().getDatabase().getType().getDisplayName() + " database connection", (plugin) -> {
+            this.database = switch (settings.getDatabase().getType()) {
+                case MYSQL, MARIADB -> new MySqlDatabase(this);
+                case POSTGRES -> new PostgresDatabase(this);
+                case MONGO -> new MongoDbDatabase(this);
+            };
+            this.database.initialize();
+        });
+
+        // Prepare redis connection
+        initialize("Redis server connection", (plugin) -> {
+            this.redisManager = new RedisManager(this);
+            this.redisManager.initialize();
+        });
+
+        // Prepare data syncer
+        initialize("data syncer", (plugin) -> {
+            dataSyncer = getSettings().getSynchronization().getMode().create(this);
+            dataSyncer.initialize();
+        });
+
+        // Register events
+        initialize("events", (plugin) -> this.eventListener = new FabricEventListener(this));
+
+        // Register plugin hooks
+        initialize("hooks", (plugin) -> {
+            if (isDependencyLoaded("Plan") && getSettings().isEnablePlanHook()) {
+                new PlanHook(this).hookIntoPlan();
+            }
+        });
+
+        // Register API
+        initialize("api", (plugin) -> FabricHuskSyncAPI.register(this));
+
+        // Check for updates
+        this.checkForUpdates();
+    }
+
+    private void onDisable() {
+        // Handle shutdown
+        this.disabling = true;
+
+        // Close the event listener / data syncer
+        if (this.dataSyncer != null) {
+            this.dataSyncer.terminate();
+        }
+        if (this.eventListener != null) {
+            this.eventListener.handlePluginDisable();
+        }
+
+        // Cancel tasks, close audiences
+        if (audiences != null) {
+            this.audiences.close();
+        }
+        this.cancelTasks();
+
+        // Complete shutdown
+        log(Level.INFO, "Successfully disabled HuskSync v" + getPluginVersion());
+    }
+
+
+    @NotNull
+    @Override
+    public String getServerName() {
+        return serverName.getName();
+    }
+
+    @Override
+    public boolean isDependencyLoaded(@NotNull String name) {
+        return FabricLoader.getInstance().isModLoaded(name);
+    }
+
+    @Override
+    @NotNull
+    public Set<OnlineUser> getOnlineUsers() {
+        return Sets.newHashSet(playerMap.values());
+    }
+
+    @Override
+    @NotNull
+    public Optional<OnlineUser> getOnlineUser(@NotNull UUID uuid) {
+        return Optional.ofNullable(playerMap.get(uuid));
+    }
+
+    @Override
+    @NotNull
+    public Uniform getUniform() {
+        return FabricUniform.getInstance(mod.getMetadata().getId());
+    }
+
+    @Override
+    @Nullable
+    public InputStream getResource(@NotNull String name) {
+        return this.mod.findPath(name)
+            .map(path -> {
+                try {
+                    return Files.newInputStream(path);
+                } catch (IOException e) {
+                    log(Level.WARNING, "Failed to load resource: " + name, e);
+                }
+                return null;
+            })
+            .orElse(this.getClass().getClassLoader().getResourceAsStream(name));
+    }
+
+    @Override
+    @NotNull
+    public Path getConfigDirectory() {
+        final Path path = FabricLoader.getInstance().getConfigDir().resolve("husksync");
+        if (!Files.isDirectory(path)) {
+            try {
+                Files.createDirectory(path);
+            } catch (IOException e) {
+                log(Level.SEVERE, "Failed to create config directory", e);
+            }
+        }
+        return path;
+    }
+
+    @Override
+    public void log(@NotNull Level level, @NotNull String message, @NotNull Throwable... throwable) {
+        LoggingEventBuilder logEvent = logger.makeLoggingEventBuilder(
+            switch (level.getName()) {
+                case "WARNING" -> org.slf4j.event.Level.WARN;
+                case "SEVERE" -> org.slf4j.event.Level.ERROR;
+                default -> org.slf4j.event.Level.INFO;
+            }
+        );
+        if (throwable.length >= 1) {
+            logEvent = logEvent.setCause(throwable[0]);
+        }
+        logEvent.log(message);
+    }
+
+    @NotNull
+    @Override
+    public ConsoleUser getConsole() {
+        return new ConsoleUser(audiences);
+    }
+
+    @Override
+    @NotNull
+    public Version getPluginVersion() {
+        return Version.fromString(mod.getMetadata().getVersion().getFriendlyString(), "-");
+    }
+
+    @Override
+    @NotNull
+    public Version getMinecraftVersion() {
+        return Version.fromString(minecraftServer.getVersion());
+    }
+
+    @NotNull
+    @Override
+    public String getPlatformType() {
+        return PLATFORM_TYPE_ID;
+    }
+
+    @Override
+    public Optional<LegacyConverter> getLegacyConverter() {
+        return Optional.empty();
+    }
+
+    @Override
+    @NotNull
+    public FabricHuskSync getPlugin() {
+        return this;
+    }
+
+}

fabric/src/main/java/net/william278/husksync/api/FabricHuskSyncAPI.java

@@ -0,0 +1,260 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.api;
+
+import net.minecraft.item.ItemStack;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.william278.desertwell.util.ThrowingConsumer;
+import net.william278.husksync.FabricHuskSync;
+import net.william278.husksync.data.DataHolder;
+import net.william278.husksync.data.FabricData;
+import net.william278.husksync.user.FabricUser;
+import net.william278.husksync.user.OnlineUser;
+import net.william278.husksync.user.User;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Optional;
+import java.util.concurrent.CompletableFuture;
+import java.util.function.Consumer;
+
+/**
+ * The HuskSync API implementation for the Fabric platform
+ * </p>
+ * Retrieve an instance of the API class via {@link #getInstance()}.
+ */
+@SuppressWarnings("unused")
+public class FabricHuskSyncAPI extends HuskSyncAPI {
+
+    /**
+     * <b>(Internal use only)</b> - Constructor, instantiating the API.
+     */
+    @ApiStatus.Internal
+    private FabricHuskSyncAPI(@NotNull FabricHuskSync plugin) {
+        super(plugin);
+    }
+
+    /**
+     * Entrypoint to the HuskSync API on the Fabric platform - returns an instance of the API
+     *
+     * @return instance of the HuskSync API
+     * @since 3.6
+     */
+    @NotNull
+    public static FabricHuskSyncAPI getInstance() {
+        if (instance == null) {
+            throw new NotRegisteredException();
+        }
+        return (FabricHuskSyncAPI) instance;
+    }
+
+    /**
+     * <b>(Internal use only)</b> - Register the API for this platform.
+     *
+     * @param plugin the plugin instance
+     * @since 3.6
+     */
+    @ApiStatus.Internal
+    public static void register(@NotNull FabricHuskSync plugin) {
+        instance = new FabricHuskSyncAPI(plugin);
+    }
+
+
+    /**
+     * Returns a {@link OnlineUser} instance for the given Fabric {@link ServerPlayerEntity}.
+     *
+     * @param player the Fabric player to get the {@link OnlineUser} instance for
+     * @return the {@link OnlineUser} instance for the given Fabric {@link ServerPlayerEntity}
+     * @since 2.0
+     */
+    @NotNull
+    public FabricUser getUser(@NotNull ServerPlayerEntity player) {
+        return FabricUser.adapt(player, plugin);
+    }
+
+    /**
+     * Get the current {@link FabricData.Items.Inventory} of the given {@link User}
+     *
+     * @param user the user to get the inventory of
+     * @return the {@link FabricData.Items.Inventory} of the given {@link User}
+     * @since 3.6
+     */
+    public CompletableFuture<Optional<FabricData.Items.Inventory>> getCurrentInventory(@NotNull User user) {
+        return getCurrentData(user).thenApply(data -> data.flatMap(DataHolder::getInventory)
+                .map(FabricData.Items.Inventory.class::cast));
+    }
+
+    /**
+     * Get the current {@link FabricData.Items.Inventory} of the given {@link ServerPlayerEntity}
+     *
+     * @param user the user to get the inventory of
+     * @return the {@link FabricData.Items.Inventory} of the given {@link ServerPlayerEntity}
+     * @since 3.6
+     */
+    public CompletableFuture<Optional<ItemStack[]>> getCurrentInventoryContents(@NotNull User user) {
+        return getCurrentInventory(user)
+                .thenApply(inventory -> inventory.map(FabricData.Items.Inventory::getContents));
+    }
+
+    /**
+     * Set the current {@link FabricData.Items.Inventory} of the given {@link User}
+     *
+     * @param user     the user to set the inventory of
+     * @param contents the contents to set the inventory to
+     * @since 3.6
+     */
+    public void setCurrentInventory(@NotNull User user, @NotNull FabricData.Items.Inventory contents) {
+        editCurrentData(user, dataHolder -> dataHolder.setInventory(contents));
+    }
+
+    /**
+     * Set the current {@link FabricData.Items.Inventory} of the given {@link User}
+     *
+     * @param user     the user to set the inventory of
+     * @param contents the contents to set the inventory to
+     * @since 3.6
+     */
+    public void setCurrentInventoryContents(@NotNull User user, @NotNull ItemStack[] contents) {
+        editCurrentData(
+                user,
+                dataHolder -> dataHolder.getInventory().ifPresent(
+                        inv -> inv.setContents(adaptItems(contents))
+                )
+        );
+    }
+
+    /**
+     * Edit the current {@link FabricData.Items.Inventory} of the given {@link User}
+     *
+     * @param user   the user to edit the inventory of
+     * @param editor the editor to apply to the inventory
+     * @since 3.6
+     */
+    public void editCurrentInventory(@NotNull User user, ThrowingConsumer<FabricData.Items.Inventory> editor) {
+        editCurrentData(user, dataHolder -> dataHolder.getInventory()
+                .map(FabricData.Items.Inventory.class::cast)
+                .ifPresent(editor));
+    }
+
+    /**
+     * Edit the current {@link FabricData.Items.Inventory} of the given {@link User}
+     *
+     * @param user   the user to edit the inventory of
+     * @param editor the editor to apply to the inventory
+     * @since 3.6
+     */
+    public void editCurrentInventoryContents(@NotNull User user, ThrowingConsumer<ItemStack[]> editor) {
+        editCurrentData(user, dataHolder -> dataHolder.getInventory()
+                .map(FabricData.Items.Inventory.class::cast)
+                .ifPresent(inventory -> editor.accept(inventory.getContents())));
+    }
+
+    /**
+     * Get the current {@link FabricData.Items.EnderChest} of the given {@link User}
+     *
+     * @param user the user to get the ender chest of
+     * @return the {@link FabricData.Items.EnderChest} of the given {@link User}, or {@link Optional#empty()} if the
+     * user data could not be found
+     * @since 3.6
+     */
+    public CompletableFuture<Optional<FabricData.Items.EnderChest>> getCurrentEnderChest(@NotNull User user) {
+        return getCurrentData(user).thenApply(data -> data.flatMap(DataHolder::getEnderChest)
+                .map(FabricData.Items.EnderChest.class::cast));
+    }
+
+    /**
+     * Get the current {@link FabricData.Items.EnderChest} of the given {@link ServerPlayerEntity}
+     *
+     * @param user the user to get the ender chest of
+     * @return the {@link FabricData.Items.EnderChest} of the given {@link ServerPlayerEntity}, or {@link Optional#empty()} if the
+     * user data could not be found
+     * @since 3.6
+     */
+    public CompletableFuture<Optional<ItemStack[]>> getCurrentEnderChestContents(@NotNull User user) {
+        return getCurrentEnderChest(user)
+                .thenApply(enderChest -> enderChest.map(FabricData.Items.EnderChest::getContents));
+    }
+
+    /**
+     * Set the current {@link FabricData.Items.EnderChest} of the given {@link User}
+     *
+     * @param user     the user to set the ender chest of
+     * @param contents the contents to set the ender chest to
+     * @since 3.6
+     */
+    public void setCurrentEnderChest(@NotNull User user, @NotNull FabricData.Items.EnderChest contents) {
+        editCurrentData(user, dataHolder -> dataHolder.setEnderChest(contents));
+    }
+
+    /**
+     * Set the current {@link FabricData.Items.EnderChest} of the given {@link User}
+     *
+     * @param user     the user to set the ender chest of
+     * @param contents the contents to set the ender chest to
+     * @since 3.6
+     */
+    public void setCurrentEnderChestContents(@NotNull User user, @NotNull ItemStack[] contents) {
+        editCurrentData(
+                user,
+                dataHolder -> dataHolder.getEnderChest().ifPresent(
+                        enderChest -> enderChest.setContents(adaptItems(contents))
+                )
+        );
+    }
+
+    /**
+     * Edit the current {@link FabricData.Items.EnderChest} of the given {@link User}
+     *
+     * @param user   the user to edit the ender chest of
+     * @param editor the editor to apply to the ender chest
+     * @since 3.6
+     */
+    public void editCurrentEnderChest(@NotNull User user, Consumer<FabricData.Items.EnderChest> editor) {
+        editCurrentData(user, dataHolder -> dataHolder.getEnderChest()
+                .map(FabricData.Items.EnderChest.class::cast)
+                .ifPresent(editor));
+    }
+
+    /**
+     * Edit the current {@link FabricData.Items.EnderChest} of the given {@link User}
+     *
+     * @param user   the user to edit the ender chest of
+     * @param editor the editor to apply to the ender chest
+     * @since 3.6
+     */
+    public void editCurrentEnderChestContents(@NotNull User user, Consumer<ItemStack[]> editor) {
+        editCurrentData(user, dataHolder -> dataHolder.getEnderChest()
+                .map(FabricData.Items.EnderChest.class::cast)
+                .ifPresent(enderChest -> editor.accept(enderChest.getContents())));
+    }
+
+    /**
+     * Adapts an array of {@link ItemStack} to a {@link FabricData.Items} instance
+     *
+     * @param contents the contents to adapt
+     * @return the adapted {@link FabricData.Items} instance
+     * @since 3.6
+     */
+    @NotNull
+    public FabricData.Items adaptItems(@NotNull ItemStack[] contents) {
+        return FabricData.Items.ItemArray.adapt(contents);
+    }
+
+}

fabric/src/main/java/net/william278/husksync/data/FabricData.java

@@ -0,0 +1,802 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.data;
+
+import com.google.common.collect.Lists;
+import com.google.common.collect.Maps;
+import com.google.common.collect.Sets;
+import com.google.gson.annotations.SerializedName;
+import lombok.*;
+import net.fabricmc.fabric.api.dimension.v1.FabricDimensions;
+import net.minecraft.advancement.AdvancementProgress;
+import net.minecraft.advancement.PlayerAdvancementTracker;
+import net.minecraft.enchantment.EnchantmentHelper;
+import net.minecraft.entity.attribute.EntityAttribute;
+import net.minecraft.entity.attribute.EntityAttributeInstance;
+import net.minecraft.entity.attribute.EntityAttributeModifier;
+import net.minecraft.entity.effect.StatusEffect;
+import net.minecraft.entity.effect.StatusEffectInstance;
+import net.minecraft.entity.player.HungerManager;
+import net.minecraft.item.ItemStack;
+import net.minecraft.nbt.NbtCompound;
+import net.minecraft.registry.Registries;
+import net.minecraft.registry.Registry;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.minecraft.stat.StatType;
+import net.minecraft.stat.Stats;
+import net.minecraft.util.Identifier;
+import net.minecraft.util.math.Vec3d;
+import net.minecraft.world.TeleportTarget;
+import net.william278.desertwell.util.ThrowingConsumer;
+import net.william278.husksync.FabricHuskSync;
+import net.william278.husksync.HuskSync;
+import net.william278.husksync.adapter.Adaptable;
+import net.william278.husksync.user.FabricUser;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.jetbrains.annotations.Range;
+
+import java.util.*;
+
+import static net.william278.husksync.util.FabricKeyedAdapter.*;
+
+public abstract class FabricData implements Data {
+
+    @Override
+    public void apply(@NotNull UserDataHolder user, @NotNull HuskSync plugin) {
+        this.apply((FabricUser) user, (FabricHuskSync) plugin);
+    }
+
+    protected abstract void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin);
+
+    @Getter
+    public static abstract class Items extends FabricData implements Data.Items {
+
+        private final @Nullable ItemStack @NotNull [] contents;
+
+        private Items(@Nullable ItemStack @NotNull [] contents) {
+            this.contents = Arrays.stream(contents.clone())
+                    .map(i -> i == null || i.isEmpty() ? null : i)
+                    .toArray(ItemStack[]::new);
+        }
+
+        @Nullable
+        @Override
+        public Stack @NotNull [] getStack() {
+            return Arrays.stream(contents)
+                    .map(stack -> stack != null ? new Stack(
+                            stack.getItem().toString(),
+                            stack.getCount(),
+                            stack.getName().getString(),
+                            Optional.ofNullable(stack.getSubNbt(ItemStack.DISPLAY_KEY))
+                                    .flatMap(display -> Optional.ofNullable(display.get(ItemStack.LORE_KEY))
+                                            .map(lore -> ((List<String>) lore).stream().toList())) //todo check this is ok
+                                    .orElse(null),
+                            stack.getEnchantments().stream()
+                                    .map(element -> EnchantmentHelper.getIdFromNbt((NbtCompound) element))
+                                    .filter(Objects::nonNull).map(Identifier::toString)
+                                    .toList()
+                    ) : null)
+                    .toArray(Stack[]::new);
+        }
+
+        @Override
+        public void clear() {
+            Arrays.fill(contents, null);
+        }
+
+        @Override
+        public void setContents(@NotNull Data.Items contents) {
+            this.setContents(((FabricData.Items) contents).getContents());
+        }
+
+        public void setContents(@Nullable ItemStack @NotNull [] contents) {
+            // Ensure the array is the correct length for the inventory
+            if (contents.length != this.contents.length) {
+                contents = Arrays.copyOf(contents, this.contents.length);
+            }
+            System.arraycopy(contents, 0, this.contents, 0, this.contents.length);
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (obj instanceof FabricData.Items items) {
+                return Arrays.equals(contents, items.getContents());
+            }
+            return false;
+        }
+
+        @Setter
+        @Getter
+        public static class Inventory extends FabricData.Items implements Data.Items.Inventory {
+
+            @Range(from = 0, to = 8)
+            private int heldItemSlot;
+
+            public Inventory(@Nullable ItemStack @NotNull [] contents, int heldItemSlot) {
+                super(contents);
+                this.heldItemSlot = heldItemSlot;
+            }
+
+            @NotNull
+            public static FabricData.Items.Inventory from(@Nullable ItemStack @NotNull [] contents, int heldItemSlot) {
+                return new FabricData.Items.Inventory(contents, heldItemSlot);
+            }
+
+            @NotNull
+            public static FabricData.Items.Inventory from(@NotNull Collection<ItemStack> contents, int heldItemSlot) {
+                return from(contents.toArray(ItemStack[]::new), heldItemSlot);
+            }
+
+            @NotNull
+            public static FabricData.Items.Inventory empty() {
+                return new FabricData.Items.Inventory(new ItemStack[INVENTORY_SLOT_COUNT], 0);
+            }
+
+            @Override
+            public int getSlotCount() {
+                return getContents().length;
+            }
+
+            @Override
+            public void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) throws IllegalStateException {
+                final ServerPlayerEntity player = user.getPlayer();
+                player.playerScreenHandler.clearCraftingSlots();
+                player.currentScreenHandler.setCursorStack(ItemStack.EMPTY);
+                final ItemStack[] items = getContents();
+                for (int slot = 0; slot < player.getInventory().size(); slot++) {
+                    player.getInventory().setStack(slot, items[slot] == null ? ItemStack.EMPTY : items[slot]);
+                }
+                player.getInventory().selectedSlot = heldItemSlot;
+                player.playerScreenHandler.sendContentUpdates();
+                player.getInventory().updateItems();
+            }
+
+        }
+
+        public static class EnderChest extends FabricData.Items implements Data.Items.EnderChest {
+
+            private EnderChest(@Nullable ItemStack @NotNull [] contents) {
+                super(contents);
+            }
+
+            @NotNull
+            public static FabricData.Items.EnderChest adapt(@Nullable ItemStack @NotNull [] contents) {
+                return new FabricData.Items.EnderChest(contents);
+            }
+
+            @NotNull
+            public static FabricData.Items.EnderChest adapt(@NotNull Collection<ItemStack> items) {
+                return adapt(items.toArray(ItemStack[]::new));
+            }
+
+            @NotNull
+            public static FabricData.Items.EnderChest empty() {
+                return new FabricData.Items.EnderChest(new ItemStack[ENDER_CHEST_SLOT_COUNT]);
+            }
+
+            @Override
+            public void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) throws IllegalStateException {
+                final ItemStack[] items = getContents();
+                for (int slot = 0; slot < user.getPlayer().getEnderChestInventory().size(); slot++) {
+                    user.getPlayer().getEnderChestInventory().setStack(
+                            slot, items[slot] == null ? ItemStack.EMPTY : items[slot]
+                    );
+                }
+            }
+
+        }
+
+        public static class ItemArray extends FabricData.Items implements Data.Items {
+
+            private ItemArray(@Nullable ItemStack @NotNull [] contents) {
+                super(contents);
+            }
+
+            @NotNull
+            public static ItemArray adapt(@NotNull Collection<ItemStack> drops) {
+                return new ItemArray(drops.toArray(ItemStack[]::new));
+            }
+
+            @NotNull
+            public static ItemArray adapt(@Nullable ItemStack @NotNull [] drops) {
+                return new ItemArray(drops);
+            }
+
+            @Override
+            public void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) throws IllegalStateException {
+                throw new UnsupportedOperationException("A generic item array cannot be applied to a player");
+            }
+
+        }
+
+    }
+
+    @Getter
+    @AllArgsConstructor(access = AccessLevel.PRIVATE)
+    public static class PotionEffects extends FabricData implements Data.PotionEffects {
+
+        private final Collection<StatusEffectInstance> effects;
+
+        @NotNull
+        public static FabricData.PotionEffects from(@NotNull Collection<StatusEffectInstance> effects) {
+            return new FabricData.PotionEffects(effects);
+        }
+
+        @NotNull
+        public static FabricData.PotionEffects adapt(@NotNull Collection<Effect> effects) {
+            return from(effects.stream()
+                    .map(effect -> {
+                        final StatusEffect type = matchEffectType(effect.type());
+                        return type != null ? new StatusEffectInstance(
+                                type,
+                                effect.duration(),
+                                effect.amplifier(),
+                                effect.isAmbient(),
+                                effect.showParticles(),
+                                effect.hasIcon()
+                        ) : null;
+                    })
+                    .filter(Objects::nonNull)
+                    .toList()
+            );
+        }
+
+        @NotNull
+        @SuppressWarnings("unused")
+        public static FabricData.PotionEffects empty() {
+            return new FabricData.PotionEffects(List.of());
+        }
+
+        @Override
+        public void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) throws IllegalStateException {
+            final ServerPlayerEntity player = user.getPlayer();
+            player.getActiveStatusEffects().forEach((effect, instance) -> player.removeStatusEffect(effect));
+            getEffects().forEach(player::addStatusEffect);
+        }
+
+        @NotNull
+        @Override
+        public List<Effect> getActiveEffects() {
+            return effects.stream()
+                    .map(potionEffect -> {
+                        final String key = getEffectId(potionEffect.getEffectType());
+                        return key != null ? new Effect(
+                                key,
+                                potionEffect.getAmplifier(),
+                                potionEffect.getDuration(),
+                                potionEffect.isAmbient(),
+                                potionEffect.shouldShowParticles(),
+                                potionEffect.shouldShowIcon()
+                        ) : null;
+                    })
+                    .filter(Objects::nonNull)
+                    .toList();
+        }
+
+    }
+
+    @Getter
+    @Setter
+    @AllArgsConstructor(access = AccessLevel.PRIVATE)
+    @NoArgsConstructor(access = AccessLevel.PRIVATE)
+    public static class Advancements extends FabricData implements Data.Advancements {
+
+        private List<Advancement> completed;
+
+        @NotNull
+        public static FabricData.Advancements adapt(@NotNull ServerPlayerEntity player) {
+            final MinecraftServer server = Objects.requireNonNull(player.getServer(), "Server is null");
+            final List<Advancement> advancements = Lists.newArrayList();
+            forEachAdvancement(server, advancement -> {
+                final AdvancementProgress advancementProgress = player.getAdvancementTracker().getProgress(advancement);
+                final Map<String, Date> awardedCriteria = Maps.newHashMap();
+
+                advancementProgress.getObtainedCriteria().forEach((criteria) -> awardedCriteria.put(criteria,
+                        advancementProgress.getEarliestProgressObtainDate()));
+
+                // Only save the advancement if criteria has been completed
+                if (!awardedCriteria.isEmpty()) {
+                    advancements.add(Advancement.adapt(advancement.getId().toString(), awardedCriteria));
+                }
+            });
+            return new FabricData.Advancements(advancements);
+        }
+
+        @NotNull
+        public static FabricData.Advancements from(@NotNull List<Advancement> advancements) {
+            return new FabricData.Advancements(advancements);
+        }
+
+        @Override
+        public void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) throws IllegalStateException {
+            final ServerPlayerEntity player = user.getPlayer();
+            final MinecraftServer server = Objects.requireNonNull(player.getServer(), "Server is null");
+            plugin.runAsync(() -> forEachAdvancement(server, advancement -> {
+                final AdvancementProgress progress = player.getAdvancementTracker().getProgress(advancement);
+                final Optional<Advancement> record = completed.stream()
+                        .filter(r -> r.getKey().equals(advancement.getId().toString()))
+                        .findFirst();
+                if (record.isEmpty()) {
+                    return;
+                }
+
+                final Map<String, Date> criteria = record.get().getCompletedCriteria();
+                final List<String> awarded = Lists.newArrayList(progress.getObtainedCriteria());
+                this.setAdvancement(
+                        plugin, advancement, player, user,
+                        criteria.keySet().stream().filter(key -> !awarded.contains(key)).toList(),
+                        awarded.stream().filter(key -> !criteria.containsKey(key)).toList()
+                );
+            }));
+        }
+
+        private void setAdvancement(@NotNull FabricHuskSync plugin,
+                                    @NotNull net.minecraft.advancement.Advancement advancement,
+                                    @NotNull ServerPlayerEntity player,
+                                    @NotNull FabricUser user,
+                                    @NotNull List<String> toAward,
+                                    @NotNull List<String> toRevoke) {
+            plugin.runSync(() -> {
+                // Track player exp level & progress
+                final int expLevel = player.experienceLevel;
+                final float expProgress = player.experienceProgress;
+
+                // Award and revoke advancement criteria
+                final PlayerAdvancementTracker progress = player.getAdvancementTracker();
+                toAward.forEach(a -> progress.grantCriterion(advancement, a));
+                toRevoke.forEach(r -> progress.revokeCriterion(advancement, r));
+
+                // Restore player exp level & progress
+                if (!toAward.isEmpty()
+                        && (player.experienceLevel != expLevel || player.experienceProgress != expProgress)) {
+                    player.setExperienceLevel(expLevel);
+                    player.setExperiencePoints((int) (player.getNextLevelExperience() * expProgress));
+                }
+            });
+        }
+
+        // Performs a consuming function for every advancement registered on the server
+        private static void forEachAdvancement(@NotNull MinecraftServer server,
+                                               @NotNull ThrowingConsumer<net.minecraft.advancement.Advancement> con) {
+            server.getAdvancementLoader().getAdvancements().forEach(con);
+        }
+
+    }
+
+    @Getter
+    @Setter
+    @NoArgsConstructor(access = AccessLevel.PRIVATE)
+    @AllArgsConstructor(access = AccessLevel.PRIVATE)
+    public static class Location extends FabricData implements Data.Location, Adaptable {
+        @SerializedName("x")
+        private double x;
+        @SerializedName("y")
+        private double y;
+        @SerializedName("z")
+        private double z;
+        @SerializedName("yaw")
+        private float yaw;
+        @SerializedName("pitch")
+        private float pitch;
+        @SerializedName("world")
+        private World world;
+
+        @NotNull
+        public static FabricData.Location from(double x, double y, double z,
+                                               float yaw, float pitch, @NotNull World world) {
+            return new FabricData.Location(x, y, z, yaw, pitch, world);
+        }
+
+        @NotNull
+        public static FabricData.Location adapt(@NotNull ServerPlayerEntity player) {
+            return from(
+                    player.getX(),
+                    player.getY(),
+                    player.getZ(),
+                    player.getYaw(),
+                    player.getPitch(),
+                    new World(
+                            Objects.requireNonNull(
+                                    player.getWorld(), "World is null"
+                            ).getRegistryKey().getValue().toString(),
+                            UUID.nameUUIDFromBytes(
+                                    player.getWorld().getDimensionKey().getValue().toString().getBytes()
+                            ),
+                            player.getWorld().getDimensionKey().getValue().toString()
+                    )
+            );
+        }
+
+        @Override
+        public void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) throws IllegalStateException {
+            final ServerPlayerEntity player = user.getPlayer();
+            final MinecraftServer server = plugin.getMinecraftServer();
+            try {
+                player.dismountVehicle();
+                FabricDimensions.teleport(
+                        player,
+                        server.getWorld(server.getWorldRegistryKeys().stream()
+                                .filter(key -> key.getValue().equals(Identifier.tryParse(world.name())))
+                                .findFirst().orElseThrow(
+                                        () -> new IllegalStateException("Invalid world")
+                                )),
+                        new TeleportTarget(
+                                new Vec3d(x, y, z),
+                                Vec3d.ZERO,
+                                yaw,
+                                pitch
+                        )
+                );
+            } catch (Throwable e) {
+                throw new IllegalStateException("Failed to apply location", e);
+            }
+        }
+
+    }
+
+    @Getter
+    @AllArgsConstructor(access = AccessLevel.PRIVATE)
+    @NoArgsConstructor(access = AccessLevel.PRIVATE)
+    public static class Statistics extends FabricData implements Data.Statistics, Adaptable {
+
+        private static final String BLOCK_STAT_TYPE = "block";
+        private static final String ITEM_STAT_TYPE = "item";
+        private static final String ENTITY_STAT_TYPE = "entity_type";
+
+        @SerializedName("generic")
+        private Map<String, Integer> genericStatistics;
+        @SerializedName("blocks")
+        private Map<String, Map<String, Integer>> blockStatistics;
+        @SerializedName("items")
+        private Map<String, Map<String, Integer>> itemStatistics;
+        @SerializedName("entities")
+        private Map<String, Map<String, Integer>> entityStatistics;
+
+        @NotNull
+        public static FabricData.Statistics adapt(@NotNull ServerPlayerEntity player) throws IllegalStateException {
+            // Adapt typed stats
+            final Map<String, Map<String, Integer>> blocks = Maps.newHashMap(),
+                    items = Maps.newHashMap(), entities = Maps.newHashMap();
+            Registries.STAT_TYPE.getEntrySet().forEach(stat -> {
+                final Registry<?> registry = stat.getValue().getRegistry();
+
+                final String registryId = registry.getKey().getValue().getPath();
+                if (registryId.equals("custom_stat")) {
+                    return;
+                }
+                final Map<String, Integer> map = (switch (registryId) {
+                    case BLOCK_STAT_TYPE -> blocks;
+                    case ITEM_STAT_TYPE -> items;
+                    case ENTITY_STAT_TYPE -> entities;
+                    default -> throw new IllegalStateException("Unexpected value: %s".formatted(registryId));
+                }).compute(stat.getKey().getValue().toString(), (k, v) -> v == null ? Maps.newHashMap() : v);
+
+                registry.getEntrySet().forEach(entry -> {
+                    @SuppressWarnings({"unchecked", "rawtypes"}) final int value = player.getStatHandler()
+                            .getStat((StatType) stat.getValue(), entry.getValue());
+                    if (value != 0) {
+                        map.put(entry.getKey().getValue().toString(), value);
+                    }
+                });
+            });
+
+            // Add generic stats
+            final Map<String, Integer> generic = Maps.newHashMap();
+            Registries.CUSTOM_STAT.getEntrySet().forEach(stat -> {
+                final int value = player.getStatHandler().getStat(Stats.CUSTOM.getOrCreateStat(stat.getValue()));
+                if (value != 0) {
+                    generic.put(stat.getKey().getValue().toString(), value);
+                }
+            });
+
+            return new FabricData.Statistics(generic, blocks, items, entities);
+        }
+
+        @NotNull
+        public static FabricData.Statistics from(@NotNull Map<String, Integer> generic,
+                                                 @NotNull Map<String, Map<String, Integer>> blocks,
+                                                 @NotNull Map<String, Map<String, Integer>> items,
+                                                 @NotNull Map<String, Map<String, Integer>> entities) {
+            return new FabricData.Statistics(generic, blocks, items, entities);
+        }
+
+        @Override
+        public void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) {
+            final ServerPlayerEntity player = user.getPlayer();
+            genericStatistics.forEach((id, v) -> applyStat(player, id, null, v));
+            blockStatistics.forEach((id, m) -> m.forEach((b, v) -> applyStat(player, id, BLOCK_STAT_TYPE, v, b)));
+            itemStatistics.forEach((id, m) -> m.forEach((i, v) -> applyStat(player, id, ITEM_STAT_TYPE, v, i)));
+            entityStatistics.forEach((id, m) -> m.forEach((e, v) -> applyStat(player, id, ENTITY_STAT_TYPE, v, e)));
+            player.getStatHandler().updateStatSet();
+            player.getStatHandler().sendStats(player);
+        }
+
+        @SuppressWarnings("unchecked")
+        private <T> void applyStat(@NotNull ServerPlayerEntity player, @NotNull String id,
+                                   @Nullable String type, int value, @NotNull String... key) {
+            final Identifier statId = Identifier.tryParse(id);
+            if (statId == null) {
+                return;
+            }
+            if (type == null) {
+                player.getStatHandler().setStat(
+                        player,
+                        Stats.CUSTOM.getOrCreateStat(Registries.CUSTOM_STAT.get(statId)),
+                        value
+                );
+                return;
+            }
+            final Identifier typeId = Identifier.tryParse(type);
+            final StatType<T> statType = (StatType<T>) Registries.STAT_TYPE.get(typeId);
+            if (statType == null) {
+                return;
+            }
+
+            final Registry<T> typeReg = statType.getRegistry();
+            final T typeInstance = typeReg.get(Identifier.tryParse(key[0]));
+            if (typeInstance == null) {
+                return;
+            }
+
+            player.getStatHandler().setStat(player, statType.getOrCreateStat(typeInstance), value);
+        }
+
+    }
+
+    @Getter
+    @AllArgsConstructor(access = AccessLevel.PRIVATE)
+    @NoArgsConstructor(access = AccessLevel.PRIVATE)
+    public static class Attributes extends FabricData implements Data.Attributes, Adaptable {
+
+        private List<Attribute> attributes;
+
+        @NotNull
+        public static FabricData.Attributes adapt(@NotNull ServerPlayerEntity player, @NotNull HuskSync plugin) {
+            final List<Attribute> attributes = Lists.newArrayList();
+            Registries.ATTRIBUTE.forEach(id -> {
+                final EntityAttributeInstance instance = player.getAttributeInstance(id);
+                final Identifier key = Registries.ATTRIBUTE.getId(id);
+                if (instance == null || key == null) {
+                    return;
+                }
+                final Set<Modifier> modifiers = Sets.newHashSet();
+                instance.getModifiers().forEach(modifier -> modifiers.add(new Modifier(
+                        modifier.getId(),
+                        modifier.getName(),
+                        modifier.getValue(),
+                        modifier.getOperation().getId(),
+                        -1
+                )));
+                attributes.add(new Attribute(
+                        key.toString(),
+                        instance.getBaseValue(),
+                        modifiers
+                ));
+            });
+            return new FabricData.Attributes(attributes);
+        }
+
+        public Optional<Attribute> getAttribute(@NotNull EntityAttribute id) {
+            return Optional.ofNullable(Registries.ATTRIBUTE.getId(id)).map(Identifier::toString)
+                    .flatMap(key -> attributes.stream().filter(attribute -> attribute.name().equals(key)).findFirst());
+        }
+
+        @SuppressWarnings("unused")
+        public Optional<Attribute> getAttribute(@NotNull String key) {
+            final EntityAttribute attribute = matchAttribute(key);
+            if (attribute == null) {
+                return Optional.empty();
+            }
+            return getAttribute(attribute);
+        }
+
+        @Override
+        protected void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) {
+            Registries.ATTRIBUTE.forEach(id -> applyAttribute(
+                    user.getPlayer().getAttributeInstance(id),
+                    getAttribute(id).orElse(null)
+            ));
+
+        }
+
+        private static void applyAttribute(@Nullable EntityAttributeInstance instance,
+                                           @Nullable Attribute attribute) {
+            if (instance == null) {
+                return;
+            }
+            instance.setBaseValue(attribute == null ? instance.getAttribute().getDefaultValue() : attribute.baseValue());
+            instance.getModifiers().forEach(instance::removeModifier);
+            if (attribute != null) {
+                attribute.modifiers().forEach(modifier -> instance.addPersistentModifier(new EntityAttributeModifier(
+                        modifier.uuid(),
+                        modifier.name(),
+                        modifier.amount(),
+                        EntityAttributeModifier.Operation.fromId(modifier.operationType())
+                )));
+            }
+        }
+
+    }
+
+    @Getter
+    @Setter
+    @AllArgsConstructor(access = AccessLevel.PRIVATE)
+    @NoArgsConstructor(access = AccessLevel.PRIVATE)
+    public static class Health extends FabricData implements Data.Health, Adaptable {
+        @SerializedName("health")
+        private double health;
+        @SerializedName("health_scale")
+        private double healthScale;
+        @SerializedName("is_health_scaled")
+        private boolean isHealthScaled;
+
+
+        @NotNull
+        public static FabricData.Health from(double health, double scale, boolean isScaled) {
+            return new FabricData.Health(health, scale, isScaled);
+        }
+
+        @NotNull
+        public static FabricData.Health adapt(@NotNull ServerPlayerEntity player) {
+            return from(
+                    player.getHealth(),
+                    20.0f, false // Health scale is a Bukkit API feature, not used in Fabric
+            );
+        }
+
+        @Override
+        public void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) throws IllegalStateException {
+            final ServerPlayerEntity player = user.getPlayer();
+            player.setHealth((float) health);
+        }
+
+    }
+
+
+    @Getter
+    @Setter
+    @AllArgsConstructor(access = AccessLevel.PRIVATE)
+    @NoArgsConstructor(access = AccessLevel.PRIVATE)
+    public static class Hunger extends FabricData implements Data.Hunger, Adaptable {
+
+        @SerializedName("food_level")
+        private int foodLevel;
+        @SerializedName("saturation")
+        private float saturation;
+        @SerializedName("exhaustion")
+        private float exhaustion;
+
+        @NotNull
+        public static FabricData.Hunger adapt(@NotNull ServerPlayerEntity player) {
+            final HungerManager hunger = player.getHungerManager();
+            return from(hunger.getFoodLevel(), hunger.getSaturationLevel(), hunger.getExhaustion());
+        }
+
+        @NotNull
+        public static FabricData.Hunger from(int foodLevel, float saturation, float exhaustion) {
+            return new FabricData.Hunger(foodLevel, saturation, exhaustion);
+        }
+
+        @Override
+        public void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) throws IllegalStateException {
+            final ServerPlayerEntity player = user.getPlayer();
+            final HungerManager hunger = player.getHungerManager();
+            hunger.setFoodLevel(foodLevel);
+            hunger.setSaturationLevel(saturation);
+            hunger.setExhaustion(exhaustion);
+        }
+
+    }
+
+    @Getter
+    @Setter
+    @AllArgsConstructor(access = AccessLevel.PRIVATE)
+    @NoArgsConstructor(access = AccessLevel.PRIVATE)
+    public static class Experience extends FabricData implements Data.Experience, Adaptable {
+
+        @SerializedName("total_experience")
+        private int totalExperience;
+
+        @SerializedName("exp_level")
+        private int expLevel;
+
+        @SerializedName("exp_progress")
+        private float expProgress;
+
+        @NotNull
+        public static FabricData.Experience from(int totalExperience, int expLevel, float expProgress) {
+            return new FabricData.Experience(totalExperience, expLevel, expProgress);
+        }
+
+        @NotNull
+        public static FabricData.Experience adapt(@NotNull ServerPlayerEntity player) {
+            return from(player.totalExperience, player.experienceLevel, player.experienceProgress);
+        }
+
+        @Override
+        public void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) throws IllegalStateException {
+            final ServerPlayerEntity player = user.getPlayer();
+            player.totalExperience = totalExperience;
+            player.setExperienceLevel(expLevel);
+            player.setExperiencePoints((int) (player.getNextLevelExperience() * expProgress));
+        }
+
+    }
+
+    @Getter
+    @Setter
+    @AllArgsConstructor(access = AccessLevel.PRIVATE)
+    @NoArgsConstructor(access = AccessLevel.PRIVATE)
+    public static class GameMode extends FabricData implements Data.GameMode, Adaptable {
+
+        @SerializedName("game_mode")
+        private String gameMode;
+
+        @NotNull
+        public static FabricData.GameMode from(@NotNull String gameMode) {
+            return new FabricData.GameMode(gameMode);
+        }
+
+        @NotNull
+        public static FabricData.GameMode adapt(@NotNull ServerPlayerEntity player) {
+            return from(player.interactionManager.getGameMode().asString());
+        }
+
+        @Override
+        public void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) throws IllegalStateException {
+            user.getPlayer().changeGameMode(net.minecraft.world.GameMode.byName(gameMode));
+        }
+
+    }
+
+    @Getter
+    @Setter
+    @AllArgsConstructor(access = AccessLevel.PRIVATE)
+    @NoArgsConstructor(access = AccessLevel.PRIVATE)
+    public static class FlightStatus extends FabricData implements Data.FlightStatus, Adaptable {
+
+        @SerializedName("allow_flight")
+        private boolean allowFlight;
+        @SerializedName("is_flying")
+        private boolean flying;
+
+        @NotNull
+        public static FabricData.FlightStatus from(boolean allowFlight, boolean flying) {
+            return new FabricData.FlightStatus(allowFlight, allowFlight && flying);
+        }
+
+        @NotNull
+        public static FabricData.FlightStatus adapt(@NotNull ServerPlayerEntity player) {
+            return from(player.getAbilities().allowFlying, player.getAbilities().flying);
+        }
+
+        @Override
+        public void apply(@NotNull FabricUser user, @NotNull FabricHuskSync plugin) throws IllegalStateException {
+            final ServerPlayerEntity player = user.getPlayer();
+            player.getAbilities().allowFlying = allowFlight;
+            player.getAbilities().flying = allowFlight && flying;
+            player.sendAbilitiesUpdate();
+        }
+
+    }
+
+}

fabric/src/main/java/net/william278/husksync/data/FabricSerializer.java

@@ -0,0 +1,289 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.data;
+
+import com.google.gson.reflect.TypeToken;
+import com.mojang.serialization.Dynamic;
+import com.mojang.serialization.DynamicOps;
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import net.minecraft.datafixer.TypeReferences;
+import net.minecraft.item.ItemStack;
+import net.minecraft.nbt.*;
+import net.william278.desertwell.util.Version;
+import net.william278.husksync.FabricHuskSync;
+import net.william278.husksync.HuskSync;
+import net.william278.husksync.api.HuskSyncAPI;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Arrays;
+import java.util.List;
+
+import static net.william278.husksync.data.Data.Items.Inventory.*;
+
+@AllArgsConstructor(access = AccessLevel.PRIVATE)
+public abstract class FabricSerializer {
+
+    @ApiStatus.Internal
+    protected final HuskSync plugin;
+
+    @SuppressWarnings("unused")
+    public FabricSerializer(@NotNull HuskSyncAPI api) {
+        this.plugin = api.getPlugin();
+    }
+
+    @ApiStatus.Internal
+    @NotNull
+    public HuskSync getPlugin() {
+        return plugin;
+    }
+
+    public static class Inventory extends FabricSerializer implements Serializer<FabricData.Items.Inventory>,
+        ItemDeserializer {
+
+        public Inventory(@NotNull HuskSync plugin) {
+            super(plugin);
+        }
+
+        @Override
+        public FabricData.Items.Inventory deserialize(@NotNull String serialized, @NotNull Version dataMcVersion)
+            throws DeserializationException {
+            // Read item NBT from string
+            final FabricHuskSync plugin = (FabricHuskSync) getPlugin();
+            final NbtCompound root;
+            try {
+                root = StringNbtReader.parse(serialized);
+            } catch (Throwable e) {
+                throw new DeserializationException("Failed to read item NBT from string (%s)".formatted(serialized), e);
+            }
+
+            // Deserialize the inventory data
+            final NbtCompound items = root.contains(ITEMS_TAG) ? root.getCompound(ITEMS_TAG) : null;
+            return FabricData.Items.Inventory.from(
+                items != null ? getItems(items, dataMcVersion, plugin) : new ItemStack[INVENTORY_SLOT_COUNT],
+                root.contains(HELD_ITEM_SLOT_TAG) ? root.getInt(HELD_ITEM_SLOT_TAG) : 0
+            );
+        }
+
+        @Override
+        public FabricData.Items.Inventory deserialize(@NotNull String serialized) {
+            return deserialize(serialized, plugin.getMinecraftVersion());
+        }
+
+        @NotNull
+        @Override
+        public String serialize(@NotNull FabricData.Items.Inventory data) throws SerializationException {
+            try {
+                final NbtCompound root = new NbtCompound();
+                root.put(ITEMS_TAG, serializeItemArray(data.getContents()));
+                root.putInt(HELD_ITEM_SLOT_TAG, data.getHeldItemSlot());
+                return root.toString();
+            } catch (Throwable e) {
+                throw new SerializationException("Failed to serialize inventory item NBT to string", e);
+            }
+        }
+
+    }
+
+    public static class EnderChest extends FabricSerializer implements Serializer<FabricData.Items.EnderChest>,
+        ItemDeserializer {
+
+        public EnderChest(@NotNull HuskSync plugin) {
+            super(plugin);
+        }
+
+        @Override
+        public FabricData.Items.EnderChest deserialize(@NotNull String serialized, @NotNull Version dataMcVersion)
+            throws DeserializationException {
+            final FabricHuskSync plugin = (FabricHuskSync) getPlugin();
+            try {
+                final NbtCompound items = StringNbtReader.parse(serialized);
+                return FabricData.Items.EnderChest.adapt(getItems(items, dataMcVersion, plugin));
+            } catch (Throwable e) {
+                throw new DeserializationException("Failed to read item NBT from string (%s)".formatted(serialized), e);
+            }
+        }
+
+        @Override
+        public FabricData.Items.EnderChest deserialize(@NotNull String serialized) {
+            return deserialize(serialized, plugin.getMinecraftVersion());
+        }
+
+        @NotNull
+        @Override
+        public String serialize(@NotNull FabricData.Items.EnderChest data) throws SerializationException {
+            try {
+                return serializeItemArray(data.getContents()).toString();
+            } catch (Throwable e) {
+                throw new SerializationException("Failed to serialize ender chest item NBT to string", e);
+            }
+        }
+    }
+
+    private interface ItemDeserializer {
+
+        int VERSION1_16_5 = 2586;
+        int VERSION1_17_1 = 2730;
+        int VERSION1_18_2 = 2975;
+        int VERSION1_19_2 = 3120;
+        int VERSION1_19_4 = 3337;
+        int VERSION1_20_1 = 3465;
+        int VERSION1_20_2 = 3578; // Future
+        int VERSION1_20_4 = 3700; // Future
+        int VERSION1_20_5 = 3837; // Future
+        int VERSION1_21 = 3953; // Future
+
+        @NotNull
+        default ItemStack[] getItems(@NotNull NbtCompound tag, @NotNull Version mcVersion, @NotNull FabricHuskSync plugin) {
+            try {
+                if (mcVersion.compareTo(plugin.getMinecraftVersion()) < 0) {
+                    return upgradeItemStacks(tag, mcVersion, plugin);
+                }
+
+                final ItemStack[] contents = new ItemStack[tag.getInt("size")];
+                final NbtList itemList = tag.getList("items", NbtElement.COMPOUND_TYPE);
+                itemList.forEach(element -> {
+                    final NbtCompound compound = (NbtCompound) element;
+                    contents[compound.getInt("Slot")] = ItemStack.fromNbt(compound);
+                });
+                plugin.debug(Arrays.toString(contents));
+                return contents;
+            } catch (Throwable e) {
+                throw new Serializer.DeserializationException("Failed to read item NBT string (%s)".formatted(tag), e);
+            }
+        }
+
+        // Serialize items slot-by-slot
+        @NotNull
+        default NbtCompound serializeItemArray(@Nullable ItemStack @NotNull [] items) {
+            final NbtCompound container = new NbtCompound();
+            container.putInt("size", items.length);
+            final NbtList itemList = new NbtList();
+            for (int i = 0; i < items.length; i++) {
+                final ItemStack item = items[i];
+                if (item == null || item.isEmpty()) {
+                    continue;
+                }
+                NbtCompound entry = new NbtCompound();
+                entry.putInt("Slot", i);
+                item.writeNbt(entry);
+                itemList.add(entry);
+            }
+            container.put(ITEMS_TAG, itemList);
+            return container;
+        }
+
+        @NotNull
+        private ItemStack @NotNull [] upgradeItemStacks(@NotNull NbtCompound items, @NotNull Version mcVersion,
+                                                        @NotNull FabricHuskSync plugin) {
+            final int size = items.getInt("size");
+            final NbtList list = items.getList("items", NbtElement.COMPOUND_TYPE);
+            final ItemStack[] itemStacks = new ItemStack[size];
+            Arrays.fill(itemStacks, ItemStack.EMPTY);
+            for (int i = 0; i < size; i++) {
+                if (list.getCompound(i) == null) {
+                    continue;
+                }
+                final NbtCompound compound = list.getCompound(i);
+                final int slot = compound.getInt("Slot");
+                itemStacks[slot] = ItemStack.fromNbt(upgradeItemData(list.getCompound(i), mcVersion, plugin));
+            }
+            return itemStacks;
+        }
+
+
+        @NotNull
+        @SuppressWarnings({"rawtypes", "unchecked"}) // For NBTOps lookup
+        private NbtCompound upgradeItemData(@NotNull NbtCompound tag, @NotNull Version mcVersion,
+                                            @NotNull FabricHuskSync plugin) {
+            return (NbtCompound) plugin.getMinecraftServer().getDataFixer().update(
+                TypeReferences.ITEM_STACK, new Dynamic<Object>((DynamicOps) NbtOps.INSTANCE, tag),
+                getDataVersion(mcVersion), getDataVersion(plugin.getMinecraftVersion())
+            ).getValue();
+        }
+
+        private int getDataVersion(@NotNull Version mcVersion) {
+            return switch (mcVersion.toStringWithoutMetadata()) {
+                case "1.16", "1.16.1", "1.16.2", "1.16.3", "1.16.4", "1.16.5" -> VERSION1_16_5;
+                case "1.17", "1.17.1" -> VERSION1_17_1;
+                case "1.18", "1.18.1", "1.18.2" -> VERSION1_18_2;
+                case "1.19", "1.19.1", "1.19.2" -> VERSION1_19_2;
+                case "1.19.4" -> VERSION1_19_4;
+                case "1.20", "1.20.1" -> VERSION1_20_1;
+                case "1.20.2" -> VERSION1_20_2; // Future
+                case "1.20.4" -> VERSION1_20_4; // Future
+                case "1.20.5", "1.20.6" -> VERSION1_20_5; // Future
+                case "1.21" -> VERSION1_21; // Future
+                default -> VERSION1_20_1; // Current supported ver
+            };
+        }
+
+    }
+
+    public static class PotionEffects extends FabricSerializer implements Serializer<FabricData.PotionEffects> {
+
+        private static final TypeToken<List<Data.PotionEffects.Effect>> TYPE = new TypeToken<>() {
+        };
+
+        public PotionEffects(@NotNull HuskSync plugin) {
+            super(plugin);
+        }
+
+        @Override
+        public FabricData.PotionEffects deserialize(@NotNull String serialized) throws DeserializationException {
+            return FabricData.PotionEffects.adapt(
+                plugin.getGson().fromJson(serialized, TYPE.getType())
+            );
+        }
+
+        @NotNull
+        @Override
+        public String serialize(@NotNull FabricData.PotionEffects element) throws SerializationException {
+            return plugin.getGson().toJson(element.getActiveEffects());
+        }
+
+    }
+
+    public static class Advancements extends FabricSerializer implements Serializer<FabricData.Advancements> {
+
+        private static final TypeToken<List<Data.Advancements.Advancement>> TYPE = new TypeToken<>() {
+        };
+
+        public Advancements(@NotNull HuskSync plugin) {
+            super(plugin);
+        }
+
+        @Override
+        public FabricData.Advancements deserialize(@NotNull String serialized) throws DeserializationException {
+            return FabricData.Advancements.from(
+                plugin.getGson().fromJson(serialized, TYPE.getType())
+            );
+        }
+
+        @NotNull
+        @Override
+        public String serialize(@NotNull FabricData.Advancements element) throws SerializationException {
+            return plugin.getGson().toJson(element.getCompleted());
+        }
+    }
+
+}

fabric/src/main/java/net/william278/husksync/data/FabricUserDataHolder.java

@@ -0,0 +1,186 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.data;
+
+import net.minecraft.entity.player.PlayerInventory;
+import net.minecraft.item.ItemStack;
+import net.minecraft.server.network.ServerPlayerEntity;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Map;
+import java.util.Optional;
+
+import static net.william278.husksync.config.Settings.SynchronizationSettings.SaveOnDeathSettings;
+
+public interface FabricUserDataHolder extends UserDataHolder {
+
+    @Override
+    default Optional<? extends Data> getData(@NotNull Identifier id) {
+        if (!id.isCustom()) {
+            try {
+                return switch (id.getKeyValue()) {
+                    case "inventory" -> getInventory();
+                    case "ender_chest" -> getEnderChest();
+                    case "potion_effects" -> getPotionEffects();
+                    case "advancements" -> getAdvancements();
+                    case "location" -> getLocation();
+                    case "statistics" -> getStatistics();
+                    case "health" -> getHealth();
+                    case "hunger" -> getHunger();
+                    case "attributes" -> getAttributes();
+                    case "experience" -> getExperience();
+                    case "game_mode" -> getGameMode();
+                    case "flight_status" -> getFlightStatus();
+                    case "persistent_data" -> getPersistentData();
+                    default -> throw new IllegalStateException(String.format("Unexpected data type: %s", id));
+                };
+            } catch (Throwable e) {
+                getPlugin().debug("Failed to get data for key: " + id.getKeyValue(), e);
+            }
+        }
+        return Optional.ofNullable(getCustomDataStore().get(id));
+    }
+
+    @Override
+    default void setData(@NotNull Identifier id, @NotNull Data data) {
+        if (id.isCustom()) {
+            getCustomDataStore().put(id, data);
+        }
+        UserDataHolder.super.setData(id, data);
+    }
+
+    @NotNull
+    @Override
+    default Optional<Data.Items.Inventory> getInventory() {
+        final SaveOnDeathSettings death = getPlugin().getSettings().getSynchronization().getSaveOnDeath();
+        if ((isDead() && !death.isSyncDeadPlayersChangingServer())) {
+            return Optional.of(FabricData.Items.Inventory.empty());
+        }
+        final PlayerInventory inventory = getPlayer().getInventory();
+        return Optional.of(FabricData.Items.Inventory.from(
+                getCombinedInventory(inventory),
+                inventory.selectedSlot
+        ));
+    }
+
+    // Gets the player's combined inventory; their inventory, plus offhand and armor.
+    @Nullable
+    private ItemStack @NotNull [] getCombinedInventory(@NotNull PlayerInventory inv) {
+        final ItemStack[] combined = new ItemStack[inv.main.size() + inv.armor.size() + inv.offHand.size()];
+        System.arraycopy(
+                inv.main.toArray(new ItemStack[0]), 0, combined,
+                0, inv.main.size()
+        );
+        System.arraycopy(
+                inv.armor.toArray(new ItemStack[0]), 0, combined,
+                inv.main.size(), inv.armor.size()
+        );
+        System.arraycopy(
+                inv.offHand.toArray(new ItemStack[0]), 0, combined,
+                inv.main.size() + inv.armor.size(), inv.offHand.size()
+        );
+        return combined;
+    }
+
+    @NotNull
+    @Override
+    default Optional<Data.Items.EnderChest> getEnderChest() {
+        return Optional.of(FabricData.Items.EnderChest.adapt(
+                getPlayer().getEnderChestInventory().stacks
+        ));
+    }
+
+    @NotNull
+    @Override
+    default Optional<Data.PotionEffects> getPotionEffects() {
+        return Optional.of(FabricData.PotionEffects.from(getPlayer().getActiveStatusEffects().values()));
+    }
+
+    @NotNull
+    @Override
+    default Optional<Data.Advancements> getAdvancements() {
+        return Optional.of(FabricData.Advancements.adapt(getPlayer()));
+    }
+
+    @NotNull
+    @Override
+    default Optional<Data.Location> getLocation() {
+        return Optional.of(FabricData.Location.adapt(getPlayer()));
+    }
+
+    @NotNull
+    @Override
+    default Optional<Data.Statistics> getStatistics() {
+        return Optional.of(FabricData.Statistics.adapt(getPlayer()));
+    }
+
+    @Override
+    @NotNull
+    default Optional<Data.Attributes> getAttributes() {
+        return Optional.of(FabricData.Attributes.adapt(getPlayer(), getPlugin()));
+    }
+
+    @NotNull
+    @Override
+    default Optional<Data.Health> getHealth() {
+        return Optional.of(FabricData.Health.adapt(getPlayer()));
+    }
+
+    @NotNull
+    @Override
+    default Optional<Data.Hunger> getHunger() {
+        return Optional.of(FabricData.Hunger.adapt(getPlayer()));
+    }
+
+    @NotNull
+    @Override
+    default Optional<Data.Experience> getExperience() {
+        return Optional.of(FabricData.Experience.adapt(getPlayer()));
+    }
+
+    @NotNull
+    @Override
+    default Optional<Data.GameMode> getGameMode() {
+        return Optional.of(FabricData.GameMode.adapt(getPlayer()));
+    }
+
+    @NotNull
+    @Override
+    default Optional<Data.FlightStatus> getFlightStatus() {
+        return Optional.of(FabricData.FlightStatus.adapt(getPlayer()));
+    }
+
+    @NotNull
+    @Override
+    default Optional<Data.PersistentData> getPersistentData() {
+        return Optional.empty(); // Not implemented on Fabric, but maybe we'll do data keys or something
+    }
+
+    boolean isDead();
+
+    @NotNull
+    ServerPlayerEntity getPlayer();
+
+    @NotNull
+    @Override
+    Map<Identifier, Data> getCustomDataStore();
+
+}

fabric/src/main/java/net/william278/husksync/event/FabricDataSaveCallback.java

@@ -0,0 +1,90 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.event;
+
+import net.fabricmc.fabric.api.event.Event;
+import net.fabricmc.fabric.api.event.EventFactory;
+import net.minecraft.util.ActionResult;
+import net.william278.husksync.HuskSync;
+import net.william278.husksync.data.DataSnapshot;
+import net.william278.husksync.user.User;
+import org.apache.commons.lang3.function.TriFunction;
+import org.jetbrains.annotations.NotNull;
+
+public interface FabricDataSaveCallback extends FabricEventCallback<DataSaveEvent> {
+
+    @NotNull
+    Event<FabricDataSaveCallback> EVENT = EventFactory.createArrayBacked(FabricDataSaveCallback.class,
+            (listeners) -> (event) -> {
+                for (FabricDataSaveCallback listener : listeners) {
+                    final ActionResult result = listener.invoke(event);
+                    if (event.isCancelled()) {
+                        return ActionResult.CONSUME;
+                    } else if (result != ActionResult.PASS) {
+                        event.setCancelled(true);
+                        return result;
+                    }
+                }
+
+                return ActionResult.PASS;
+            });
+
+    @NotNull
+    TriFunction<User, DataSnapshot.Packed, HuskSync, DataSaveEvent> SUPPLIER = (user, data, plugin) ->
+
+            new DataSaveEvent() {
+                private boolean cancelled = false;
+
+                @Override
+                public boolean isCancelled() {
+                    return cancelled;
+                }
+
+                @Override
+                public void setCancelled(boolean cancelled) {
+                    this.cancelled = cancelled;
+                }
+
+                @NotNull
+                @Override
+                public DataSnapshot.Packed getData() {
+                    return data;
+                }
+
+                @NotNull
+                @Override
+                public HuskSync getPlugin() {
+                    return plugin;
+                }
+
+                @NotNull
+                @Override
+                public User getUser() {
+                    return user;
+                }
+
+                @NotNull
+                @SuppressWarnings("unused")
+                public Event<FabricDataSaveCallback> getEvent() {
+                    return EVENT;
+                }
+            };
+
+}

fabric/src/main/java/net/william278/husksync/event/FabricEventCallback.java

@@ -17,13 +17,14 @@
  *  limitations under the License.
  */
 
-package net.william278.husksync.command;
+package net.william278.husksync.event;
 
-import net.william278.husksync.user.CommandUser;
+import net.minecraft.util.ActionResult;
 import org.jetbrains.annotations.NotNull;
 
-public interface Executable {
+public interface FabricEventCallback<E extends Event> {
 
-    void onExecuted(@NotNull CommandUser executor, @NotNull String[] args);
+    @NotNull
+    ActionResult invoke(@NotNull E event);
 
 }

fabric/src/main/java/net/william278/husksync/event/FabricEventDispatcher.java

@@ -0,0 +1,70 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.event;
+
+import net.minecraft.util.ActionResult;
+import net.william278.husksync.data.DataSnapshot;
+import net.william278.husksync.user.OnlineUser;
+import net.william278.husksync.user.User;
+import org.jetbrains.annotations.NotNull;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.logging.Level;
+
+public interface FabricEventDispatcher extends EventDispatcher {
+
+    @SuppressWarnings("unchecked")
+    @Override
+    default <T extends Event> boolean fireIsCancelled(@NotNull T event) {
+        try {
+            final Method field = event.getClass().getDeclaredMethod("getEvent");
+            field.setAccessible(true);
+
+            net.fabricmc.fabric.api.event.Event<?> fabricEvent =
+                    (net.fabricmc.fabric.api.event.Event<?>) field.invoke(event);
+
+            final FabricEventCallback<T> invoker = (FabricEventCallback<T>) fabricEvent.invoker();
+            return invoker.invoke(event) == ActionResult.FAIL;
+        } catch (InvocationTargetException | NoSuchMethodException | IllegalAccessException e) {
+            getPlugin().log(Level.WARNING, "Failed to fire event (" + event.getClass().getName() + ")", e);
+            return false;
+        }
+    }
+
+    @NotNull
+    @Override
+    default PreSyncEvent getPreSyncEvent(@NotNull OnlineUser user, @NotNull DataSnapshot.Packed userData) {
+        return FabricPreSyncCallback.SUPPLIER.apply(user, userData, getPlugin());
+    }
+
+    @NotNull
+    @Override
+    default DataSaveEvent getDataSaveEvent(@NotNull User user, @NotNull DataSnapshot.Packed saveCause) {
+        return FabricDataSaveCallback.SUPPLIER.apply(user, saveCause, getPlugin());
+    }
+
+    @NotNull
+    @Override
+    default SyncCompleteEvent getSyncCompleteEvent(@NotNull OnlineUser user) {
+        return FabricSyncCompleteCallback.SUPPLIER.apply(user, getPlugin());
+    }
+
+}

fabric/src/main/java/net/william278/husksync/event/FabricPreSyncCallback.java

@@ -0,0 +1,90 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.event;
+
+import net.fabricmc.fabric.api.event.Event;
+import net.fabricmc.fabric.api.event.EventFactory;
+import net.minecraft.util.ActionResult;
+import net.william278.husksync.HuskSync;
+import net.william278.husksync.data.DataSnapshot;
+import net.william278.husksync.user.OnlineUser;
+import org.apache.commons.lang3.function.TriFunction;
+import org.jetbrains.annotations.NotNull;
+
+public interface FabricPreSyncCallback extends FabricEventCallback<PreSyncEvent> {
+
+    @NotNull
+    Event<FabricPreSyncCallback> EVENT = EventFactory.createArrayBacked(FabricPreSyncCallback.class,
+            (listeners) -> (event) -> {
+                for (FabricPreSyncCallback listener : listeners) {
+                    final ActionResult result = listener.invoke(event);
+                    if (event.isCancelled()) {
+                        return ActionResult.CONSUME;
+                    } else if (result != ActionResult.PASS) {
+                        event.setCancelled(true);
+                        return result;
+                    }
+                }
+
+                return ActionResult.PASS;
+            });
+
+    @NotNull
+    TriFunction<OnlineUser, DataSnapshot.Packed, HuskSync, PreSyncEvent> SUPPLIER = (user, data, plugin) ->
+
+            new PreSyncEvent() {
+                private boolean cancelled = false;
+
+                @Override
+                public boolean isCancelled() {
+                    return cancelled;
+                }
+
+                @Override
+                public void setCancelled(boolean cancelled) {
+                    this.cancelled = cancelled;
+                }
+
+                @NotNull
+                @Override
+                public DataSnapshot.Packed getData() {
+                    return data;
+                }
+
+                @NotNull
+                @Override
+                public HuskSync getPlugin() {
+                    return plugin;
+                }
+
+                @NotNull
+                @Override
+                public OnlineUser getUser() {
+                    return user;
+                }
+
+                @NotNull
+                @SuppressWarnings("unused")
+                public Event<FabricPreSyncCallback> getEvent() {
+                    return EVENT;
+                }
+            };
+
+}

fabric/src/main/java/net/william278/husksync/event/FabricSyncCompleteCallback.java

@@ -0,0 +1,61 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.event;
+
+import net.fabricmc.fabric.api.event.Event;
+import net.fabricmc.fabric.api.event.EventFactory;
+import net.minecraft.util.ActionResult;
+import net.william278.husksync.HuskSync;
+import net.william278.husksync.user.OnlineUser;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.function.BiFunction;
+
+public interface FabricSyncCompleteCallback extends FabricEventCallback<SyncCompleteEvent> {
+
+    @NotNull
+    Event<FabricSyncCompleteCallback> EVENT = EventFactory.createArrayBacked(FabricSyncCompleteCallback.class,
+            (listeners) -> (event) -> {
+                for (FabricSyncCompleteCallback listener : listeners) {
+                    listener.invoke(event);
+                }
+
+                return ActionResult.PASS;
+            });
+
+    @NotNull
+    BiFunction<OnlineUser, HuskSync, SyncCompleteEvent> SUPPLIER = (user, plugin) ->
+
+            new SyncCompleteEvent() {
+
+                @NotNull
+                @Override
+                public OnlineUser getUser() {
+                    return user;
+                }
+
+                @NotNull
+                @SuppressWarnings("unused")
+                public Event<FabricSyncCompleteCallback> getEvent() {
+                    return EVENT;
+                }
+            };
+
+}

fabric/src/main/java/net/william278/husksync/event/InventoryClickCallback.java

@@ -0,0 +1,48 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.event;
+
+import net.fabricmc.fabric.api.event.Event;
+import net.fabricmc.fabric.api.event.EventFactory;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.ActionResult;
+import org.jetbrains.annotations.NotNull;
+
+public interface InventoryClickCallback {
+
+    @NotNull
+    Event<InventoryClickCallback> EVENT = EventFactory.createArrayBacked(InventoryClickCallback.class,
+            (listeners) -> (player, itemStack) -> {
+                for (InventoryClickCallback listener : listeners) {
+                    ActionResult result = listener.interact(player, itemStack);
+
+                    if (result != ActionResult.PASS) {
+                        return result;
+                    }
+                }
+
+                return ActionResult.PASS;
+            });
+
+    @NotNull
+    ActionResult interact(PlayerEntity player, ItemStack sheep);
+
+}

fabric/src/main/java/net/william278/husksync/event/ItemDropCallback.java

@@ -0,0 +1,48 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.event;
+
+import net.fabricmc.fabric.api.event.Event;
+import net.fabricmc.fabric.api.event.EventFactory;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.ActionResult;
+import org.jetbrains.annotations.NotNull;
+
+public interface ItemDropCallback {
+
+    @NotNull
+    Event<ItemDropCallback> EVENT = EventFactory.createArrayBacked(ItemDropCallback.class,
+            (listeners) -> (player, itemStack) -> {
+                for (ItemDropCallback listener : listeners) {
+                    ActionResult result = listener.interact(player, itemStack);
+
+                    if (result != ActionResult.PASS) {
+                        return result;
+                    }
+                }
+
+                return ActionResult.PASS;
+            });
+
+    @NotNull
+    ActionResult interact(PlayerEntity player, ItemStack sheep);
+
+}

fabric/src/main/java/net/william278/husksync/event/ItemPickupCallback.java

@@ -0,0 +1,48 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.event;
+
+import net.fabricmc.fabric.api.event.Event;
+import net.fabricmc.fabric.api.event.EventFactory;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.ActionResult;
+import org.jetbrains.annotations.NotNull;
+
+public interface ItemPickupCallback {
+
+    @NotNull
+    Event<ItemPickupCallback> EVENT = EventFactory.createArrayBacked(ItemPickupCallback.class,
+            (listeners) -> (player, itemStack) -> {
+                for (ItemPickupCallback listener : listeners) {
+                    ActionResult result = listener.interact(player, itemStack);
+
+                    if (result != ActionResult.PASS) {
+                        return result;
+                    }
+                }
+
+                return ActionResult.PASS;
+            });
+
+    @NotNull
+    ActionResult interact(PlayerEntity player, ItemStack sheep);
+
+}

fabric/src/main/java/net/william278/husksync/event/PlayerCommandCallback.java

@@ -0,0 +1,47 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.event;
+
+import net.fabricmc.fabric.api.event.Event;
+import net.fabricmc.fabric.api.event.EventFactory;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.util.ActionResult;
+import org.jetbrains.annotations.NotNull;
+
+public interface PlayerCommandCallback {
+
+    @NotNull
+    Event<PlayerCommandCallback> EVENT = EventFactory.createArrayBacked(PlayerCommandCallback.class,
+            (listeners) -> (player, command) -> {
+                for (PlayerCommandCallback listener : listeners) {
+                    ActionResult result = listener.interact(player, command);
+
+                    if (result != ActionResult.PASS) {
+                        return result;
+                    }
+                }
+
+                return ActionResult.PASS;
+            });
+
+    @NotNull
+    ActionResult interact(PlayerEntity player, String command);
+
+}

fabric/src/main/java/net/william278/husksync/event/PlayerDeathDropsCallback.java

@@ -0,0 +1,44 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.event;
+
+import net.fabricmc.fabric.api.event.Event;
+import net.fabricmc.fabric.api.event.EventFactory;
+import net.minecraft.item.ItemStack;
+import net.minecraft.server.network.ServerPlayerEntity;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Arrays;
+
+public interface PlayerDeathDropsCallback {
+
+    @NotNull
+    Event<PlayerDeathDropsCallback> EVENT = EventFactory.createArrayBacked(
+            PlayerDeathDropsCallback.class,
+            (listeners) -> (player, itemsToKeep, itemsToDrop) -> Arrays.stream(listeners)
+                    .forEach(listener -> listener.drops(player, itemsToKeep, itemsToDrop))
+    );
+
+    void drops(@NotNull ServerPlayerEntity player,
+               @Nullable ItemStack @NotNull [] itemsToKeep,
+               @Nullable ItemStack @NotNull [] itemsToDrop);
+
+}

fabric/src/main/java/net/william278/husksync/event/WorldSaveCallback.java

@@ -0,0 +1,39 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.event;
+
+import net.fabricmc.fabric.api.event.Event;
+import net.fabricmc.fabric.api.event.EventFactory;
+import net.minecraft.server.world.ServerWorld;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Arrays;
+
+public interface WorldSaveCallback {
+
+    @NotNull
+    Event<WorldSaveCallback> EVENT = EventFactory.createArrayBacked(
+            WorldSaveCallback.class,
+            (listeners) -> (world) -> Arrays.stream(listeners).forEach(listener -> listener.save(world))
+    );
+
+    void save(@NotNull ServerWorld world);
+
+}

fabric/src/main/java/net/william278/husksync/listener/FabricEventListener.java

@@ -0,0 +1,158 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.listener;
+
+import net.fabricmc.fabric.api.entity.event.v1.ServerLivingEntityEvents;
+import net.fabricmc.fabric.api.event.player.PlayerBlockBreakEvents;
+import net.fabricmc.fabric.api.event.player.UseBlockCallback;
+import net.fabricmc.fabric.api.event.player.UseEntityCallback;
+import net.fabricmc.fabric.api.event.player.UseItemCallback;
+import net.fabricmc.fabric.api.networking.v1.PacketSender;
+import net.fabricmc.fabric.api.networking.v1.ServerPlayConnectionEvents;
+import net.minecraft.block.BlockState;
+import net.minecraft.block.entity.BlockEntity;
+import net.minecraft.entity.Entity;
+import net.minecraft.entity.LivingEntity;
+import net.minecraft.entity.damage.DamageSource;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.item.ItemStack;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.network.ServerPlayNetworkHandler;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.minecraft.server.world.ServerWorld;
+import net.minecraft.util.ActionResult;
+import net.minecraft.util.Hand;
+import net.minecraft.util.TypedActionResult;
+import net.minecraft.util.hit.BlockHitResult;
+import net.minecraft.util.hit.EntityHitResult;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.World;
+import net.william278.husksync.FabricHuskSync;
+import net.william278.husksync.HuskSync;
+import net.william278.husksync.config.Settings.SynchronizationSettings.SaveOnDeathSettings;
+import net.william278.husksync.data.FabricData;
+import net.william278.husksync.event.*;
+import net.william278.husksync.user.FabricUser;
+import net.william278.husksync.user.OnlineUser;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.stream.Collectors;
+
+public class FabricEventListener extends EventListener implements LockedHandler {
+
+    public FabricEventListener(@NotNull HuskSync plugin) {
+        super(plugin);
+        this.registerEvents();
+    }
+
+    public void registerEvents() {
+        ServerPlayConnectionEvents.JOIN.register(this::handlePlayerJoin);
+        ServerPlayConnectionEvents.DISCONNECT.register(this::handlePlayerQuit);
+        WorldSaveCallback.EVENT.register(this::handleWorldSave);
+        PlayerDeathDropsCallback.EVENT.register(this::handlePlayerDeathDrops);
+
+        // Locked events handling
+        ItemPickupCallback.EVENT.register(this::handleItemPickup);
+        ItemDropCallback.EVENT.register(this::handleItemDrop);
+        UseBlockCallback.EVENT.register(this::handleBlockInteract);
+        UseEntityCallback.EVENT.register(this::handleEntityInteract);
+        UseItemCallback.EVENT.register(this::handleItemInteract);
+        PlayerBlockBreakEvents.BEFORE.register(this::handleBlockBreak);
+        ServerLivingEntityEvents.ALLOW_DAMAGE.register(this::handleEntityDamage);
+        InventoryClickCallback.EVENT.register(this::handleInventoryClick);
+        PlayerCommandCallback.EVENT.register(this::handlePlayerCommand);
+    }
+
+    private void handlePlayerJoin(@NotNull ServerPlayNetworkHandler handler, @NotNull PacketSender sender,
+                                  @NotNull MinecraftServer server) {
+        final FabricUser user = FabricUser.adapt(handler.player, plugin);
+        ((FabricHuskSync) plugin).getPlayerMap().put(handler.player.getUuid(), user);
+        handlePlayerJoin(user);
+    }
+
+    private void handlePlayerQuit(@NotNull ServerPlayNetworkHandler handler, @NotNull MinecraftServer server) {
+        ((FabricHuskSync) plugin).getPlayerMap().remove(handler.player.getUuid());
+        handlePlayerQuit(FabricUser.adapt(handler.player, plugin));
+    }
+
+    private void handleWorldSave(@NotNull ServerWorld world) {
+        this.saveOnWorldSave(
+                world.getPlayers().stream().map(player -> (OnlineUser) FabricUser.adapt(player, plugin)).toList()
+        );
+    }
+
+    private void handlePlayerDeathDrops(@NotNull ServerPlayerEntity player, @Nullable ItemStack @NotNull [] toKeep,
+                                        @Nullable ItemStack @NotNull [] toDrop) {
+        final SaveOnDeathSettings settings = plugin.getSettings().getSynchronization().getSaveOnDeath();
+        this.saveOnPlayerDeath(
+                FabricUser.adapt(player, plugin),
+                FabricData.Items.ItemArray.adapt(
+                        settings.getItemsToSave() == SaveOnDeathSettings.DeathItemsMode.DROPS ? toDrop : toKeep
+                )
+        );
+    }
+
+    private ActionResult handleItemPickup(PlayerEntity player, ItemStack itemStack) {
+        return (cancelPlayerEvent(player.getUuid())) ? ActionResult.FAIL : ActionResult.PASS;
+    }
+
+    private ActionResult handleItemDrop(PlayerEntity player, ItemStack itemStack) {
+        return (cancelPlayerEvent(player.getUuid())) ? ActionResult.FAIL : ActionResult.PASS;
+    }
+
+    private ActionResult handleBlockInteract(PlayerEntity player, World world, Hand hand, BlockHitResult blockHitResult) {
+        return (cancelPlayerEvent(player.getUuid())) ? ActionResult.FAIL : ActionResult.PASS;
+    }
+
+    private ActionResult handleEntityInteract(PlayerEntity player, World world, Hand hand, Entity entity, EntityHitResult entityHitResult) {
+        return (cancelPlayerEvent(player.getUuid())) ? ActionResult.FAIL : ActionResult.PASS;
+    }
+
+    private TypedActionResult<ItemStack> handleItemInteract(PlayerEntity player, World world, Hand hand) {
+        ItemStack stackInHand = player.getStackInHand(hand);
+        return (cancelPlayerEvent(player.getUuid())) ? TypedActionResult.fail(stackInHand) : TypedActionResult.pass(stackInHand);
+    }
+
+    private boolean handleBlockBreak(World world, PlayerEntity player, BlockPos blockPos, BlockState blockState, BlockEntity blockEntity) {
+        return !cancelPlayerEvent(player.getUuid());
+    }
+
+    private boolean handleEntityDamage(LivingEntity livingEntity, DamageSource damageSource, float v) {
+        if (livingEntity instanceof ServerPlayerEntity player) {
+            return !cancelPlayerEvent(player.getUuid());
+        }
+        return true;
+    }
+
+    private ActionResult handleInventoryClick(PlayerEntity player, ItemStack itemStack) {
+        return (cancelPlayerEvent(player.getUuid())) ? ActionResult.FAIL : ActionResult.PASS;
+    }
+
+    private ActionResult handlePlayerCommand(PlayerEntity player, String s) {
+        return (cancelPlayerEvent(player.getUuid())) ? ActionResult.FAIL : ActionResult.PASS;
+    }
+
+    @Override
+    @NotNull
+    public HuskSync getPlugin() {
+        return plugin;
+    }
+}

fabric/src/main/java/net/william278/husksync/mixins/ItemEntityMixin.java

@@ -0,0 +1,45 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.mixins;
+
+import net.minecraft.entity.ItemEntity;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.ActionResult;
+import net.william278.husksync.event.ItemPickupCallback;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(ItemEntity.class)
+public class ItemEntityMixin {
+
+    @Inject(method = "onPlayerCollision", at = @At("HEAD"), cancellable = true)
+    private void onPlayerPickupItem(PlayerEntity player, CallbackInfo ci) {
+        final ItemStack stack = ((ItemEntity) (Object) this).getStack();
+        final ActionResult result = ItemPickupCallback.EVENT.invoker().interact(player, stack);
+
+        if (result == ActionResult.FAIL) {
+            ci.cancel();
+        }
+    }
+
+}

fabric/src/main/java/net/william278/husksync/mixins/PlayerEntityMixin.java

@@ -0,0 +1,81 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.mixins;
+
+import net.minecraft.enchantment.EnchantmentHelper;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.entity.player.PlayerInventory;
+import net.minecraft.item.ItemStack;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.william278.husksync.event.PlayerDeathDropsCallback;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.Unique;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(PlayerEntity.class)
+public class PlayerEntityMixin {
+
+    @Final
+    @Shadow
+    private PlayerInventory inventory;
+
+    @Inject(method = "dropInventory", at = @At(value = "INVOKE", target = "Lnet/minecraft/entity/player/PlayerEntity;vanishCursedItems()V"))
+    protected void dropInventory(@NotNull CallbackInfo ci) {
+        final PlayerEntity player = (PlayerEntity) (Object) this;
+        PlayerDeathDropsCallback.EVENT.invoker().drops((ServerPlayerEntity) player, getItemsToKeep(), getItemsToDrop());
+    }
+
+    @Unique
+    @Nullable
+    private ItemStack @NotNull [] getItemsToKeep() {
+        final @Nullable ItemStack @NotNull [] toKeep = new ItemStack[inventory.size()];
+        for (int i = 0; i < inventory.size(); ++i) {
+            ItemStack itemStack = inventory.getStack(i);
+            if (!itemStack.isEmpty() && EnchantmentHelper.hasVanishingCurse(itemStack)) {
+                toKeep[i] = null;
+                continue;
+            }
+            toKeep[i] = itemStack;
+        }
+        return toKeep;
+    }
+
+    @Unique
+    @Nullable
+    private ItemStack @NotNull [] getItemsToDrop() {
+        final @Nullable ItemStack @NotNull [] toDrop = new ItemStack[inventory.size()];
+        for (int i = 0; i < inventory.size(); ++i) {
+            ItemStack itemStack = inventory.getStack(i);
+            if (!itemStack.isEmpty() && EnchantmentHelper.hasVanishingCurse(itemStack)) {
+                toDrop[i] = itemStack;
+                continue;
+            }
+            toDrop[i] = null;
+        }
+        return toDrop;
+    }
+
+}

fabric/src/main/java/net/william278/husksync/mixins/ServerPlayNetworkHandlerMixin.java

@@ -0,0 +1,107 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.mixins;
+
+import net.minecraft.item.ItemStack;
+import net.minecraft.network.packet.Packet;
+import net.minecraft.network.packet.c2s.play.ClickSlotC2SPacket;
+import net.minecraft.network.packet.c2s.play.CommandExecutionC2SPacket;
+import net.minecraft.network.packet.c2s.play.CreativeInventoryActionC2SPacket;
+import net.minecraft.network.packet.c2s.play.PlayerActionC2SPacket;
+import net.minecraft.network.packet.s2c.play.ScreenHandlerSlotUpdateS2CPacket;
+import net.minecraft.server.network.ServerPlayNetworkHandler;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.minecraft.util.ActionResult;
+import net.minecraft.util.Hand;
+import net.william278.husksync.event.ItemDropCallback;
+import net.william278.husksync.event.PlayerCommandCallback;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+// Adapted from simplerauth (https://github.com/lolicode-org/simplerauth), which is licensed under the MIT License
+@Mixin(ServerPlayNetworkHandler.class)
+public abstract class ServerPlayNetworkHandlerMixin {
+    @Shadow
+    public ServerPlayerEntity player;
+
+    @Shadow
+    public abstract void sendPacket(Packet<?> packet);
+
+    @Inject(method = "onPlayerAction", at = @At("HEAD"), cancellable = true)
+    public void onPlayerAction(PlayerActionC2SPacket packet, CallbackInfo ci) {
+        if (packet.getAction() == PlayerActionC2SPacket.Action.DROP_ITEM
+                || packet.getAction() == PlayerActionC2SPacket.Action.DROP_ALL_ITEMS) {
+            ItemStack stack = player.getStackInHand(Hand.MAIN_HAND);
+            ActionResult result = ItemDropCallback.EVENT.invoker().interact(player, stack);
+
+            if (result == ActionResult.FAIL) {
+                ci.cancel();
+                this.sendPacket(new ScreenHandlerSlotUpdateS2CPacket(
+                        -2,
+                        1,
+                        player.getInventory().getSlotWithStack(stack),
+                        stack
+                ));
+            }
+        }
+    }
+
+    @Inject(method = "onClickSlot", at = @At("HEAD"), cancellable = true)
+    public void onClickSlot(ClickSlotC2SPacket packet, CallbackInfo ci) {
+        int slot = packet.getSlot();
+        if (slot < 0) return;
+
+        ItemStack stack = this.player.getInventory().getStack(slot);
+        ActionResult result = ItemDropCallback.EVENT.invoker().interact(player, stack);
+
+        if (result == ActionResult.FAIL) {
+            ci.cancel();
+            this.sendPacket(new ScreenHandlerSlotUpdateS2CPacket(-2, 1, slot, stack));
+            this.sendPacket(new ScreenHandlerSlotUpdateS2CPacket(-1, 1, -1, ItemStack.EMPTY));
+        }
+    }
+
+    @Inject(method = "onCreativeInventoryAction", at = @At("HEAD"), cancellable = true)
+    public void onCreativeInventoryAction(CreativeInventoryActionC2SPacket packet, CallbackInfo ci) {
+        int slot = packet.getSlot();
+        if (slot < 0) return;
+
+        ItemStack stack = this.player.getInventory().getStack(slot);
+        ActionResult result = ItemDropCallback.EVENT.invoker().interact(player, stack);
+
+        if (result == ActionResult.FAIL) {
+            ci.cancel();
+            this.sendPacket(new ScreenHandlerSlotUpdateS2CPacket(-2, 1, slot, stack));
+            this.sendPacket(new ScreenHandlerSlotUpdateS2CPacket(-1, 1, -1, ItemStack.EMPTY));
+        }
+    }
+
+    @Inject(method = "onCommandExecution", at = @At("HEAD"), cancellable = true)
+    public void onCommandExecution(CommandExecutionC2SPacket packet, CallbackInfo ci) {
+        ActionResult result = PlayerCommandCallback.EVENT.invoker().interact(player, packet.command());
+
+        if (result == ActionResult.FAIL) {
+            ci.cancel();
+        }
+    }
+}

fabric/src/main/java/net/william278/husksync/mixins/ServerPlayerEntityMixin.java

@@ -0,0 +1,47 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.mixins;
+
+import net.minecraft.entity.ItemEntity;
+import net.minecraft.item.ItemStack;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.minecraft.util.ActionResult;
+import net.william278.husksync.event.ItemDropCallback;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+@Mixin(ServerPlayerEntity.class)
+public class ServerPlayerEntityMixin {
+
+    @Inject(method = "dropItem", at = @At("HEAD"), cancellable = true)
+    private void onPlayerDropItem(ItemStack stack, boolean dropAtFeet, boolean saveThrower,
+                                  final CallbackInfoReturnable<ItemEntity> ci) {
+        final ServerPlayerEntity player = (ServerPlayerEntity) (Object) this;
+        final ActionResult result = ItemDropCallback.EVENT.invoker().interact(player, stack);
+
+        if (result == ActionResult.FAIL) {
+            ci.cancel();
+        }
+    }
+
+}

fabric/src/main/java/net/william278/husksync/mixins/ServerWorldMixin.java

@@ -0,0 +1,47 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.mixins;
+
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.world.ServerWorld;
+import net.william278.husksync.event.WorldSaveCallback;
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(ServerWorld.class)
+public class ServerWorldMixin {
+
+    @Final
+    @Shadow
+    private MinecraftServer server;
+
+    @Inject(method = "saveLevel", at = @At("HEAD"))
+    public void saveLevel(CallbackInfo ci) {
+        if (server.isStopping() || server.isStopped()) {
+            return;
+        }
+        WorldSaveCallback.EVENT.invoker().save((ServerWorld) (Object) this);
+    }
+
+}

fabric/src/main/java/net/william278/husksync/user/FabricUser.java

@@ -0,0 +1,175 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.user;
+
+import de.themoep.minedown.adventure.MineDown;
+import eu.pb4.sgui.api.ClickType;
+import eu.pb4.sgui.api.elements.GuiElementInterface;
+import eu.pb4.sgui.api.gui.SimpleGui;
+import me.lucko.fabric.api.permissions.v0.Permissions;
+import net.kyori.adventure.audience.Audience;
+import net.kyori.adventure.platform.fabric.FabricServerAudiences;
+import net.minecraft.item.ItemStack;
+import net.minecraft.screen.GenericContainerScreenHandler;
+import net.minecraft.screen.ScreenHandlerType;
+import net.minecraft.screen.slot.SlotActionType;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.william278.husksync.FabricHuskSync;
+import net.william278.husksync.HuskSync;
+import net.william278.husksync.data.Data;
+import net.william278.husksync.data.FabricData;
+import net.william278.husksync.data.FabricUserDataHolder;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.function.Consumer;
+
+public class FabricUser extends OnlineUser implements FabricUserDataHolder {
+
+    private final HuskSync plugin;
+    private final ServerPlayerEntity player;
+
+    private FabricUser(@NotNull ServerPlayerEntity player, @NotNull HuskSync plugin) {
+        super(player.getUuid(), player.getName().getString());
+        this.player = player;
+        this.plugin = plugin;
+    }
+
+    @NotNull
+    @ApiStatus.Internal
+    public static FabricUser adapt(@NotNull ServerPlayerEntity player, @NotNull HuskSync plugin) {
+        return new FabricUser(player, plugin);
+    }
+
+    @Override
+    public boolean isOffline() {
+        return player == null || player.isDisconnected();
+    }
+
+    @NotNull
+    @Override
+    public Audience getAudience() {
+        return plugin.getAudiences().player(player.getUuid());
+    }
+
+    @Override
+    public void sendToast(@NotNull MineDown title, @NotNull MineDown description, @NotNull String iconMaterial,
+                          @NotNull String backgroundType) {
+        getAudience().sendActionBar(title.toComponent()); // Toasts unimplemented for now
+    }
+
+    @Override
+    public void showGui(@NotNull Data.Items.Items items, @NotNull MineDown title, boolean editable, int size,
+                        @NotNull Consumer<Data.Items> onClose) {
+        plugin.runSync(
+                () -> new ItemViewerGui(size, player, title, (FabricData.Items) items, onClose, editable, plugin).open()
+        );
+    }
+
+    private static class ItemViewerGui extends SimpleGui {
+
+        private final Consumer<Data.Items> onClose;
+        private final int size;
+        private final boolean editable;
+
+        public ItemViewerGui(int size, @NotNull ServerPlayerEntity player, @NotNull MineDown title,
+                             @NotNull FabricData.Items items, @NotNull Consumer<Data.Items> onClose,
+                             boolean editable, @NotNull HuskSync plugin) {
+            super(getScreenHandler(size), player, false);
+            this.onClose = onClose;
+            this.size = size;
+            this.editable = editable;
+
+            // Set title, items
+            this.setTitle(((FabricServerAudiences) plugin.getAudiences()).toNative(title.toComponent()));
+            this.setLockPlayerInventory(!editable);
+            for (int i = 0; i < size; i++) {
+                final ItemStack item = items.getContents()[i];
+                this.setSlot(i, item == null ? ItemStack.EMPTY : item);
+            }
+        }
+
+        @Override
+        public void onClose() {
+            final ItemStack[] contents = new ItemStack[size];
+            for (int i = 0; i < size; i++) {
+                contents[i] = this.getSlot(i) == null ? null : this.getSlot(i).getItemStack();
+            }
+            onClose.accept(FabricData.Items.ItemArray.adapt(contents));
+        }
+
+        @Override
+        public boolean onAnyClick(int index, @NotNull ClickType type, @NotNull SlotActionType action) {
+            return editable;
+        }
+
+        @Override
+        public boolean onClick(int index, @NotNull ClickType type, @NotNull SlotActionType action,
+                               @NotNull GuiElementInterface element) {
+            return editable;
+        }
+
+        @NotNull
+        private static ScreenHandlerType<GenericContainerScreenHandler> getScreenHandler(int size) {
+            return switch (size / 9 + (size % 9 == 0 ? 0 : 1)) {
+                case 3 -> ScreenHandlerType.GENERIC_9X3;
+                case 4 -> ScreenHandlerType.GENERIC_9X4;
+                case 5 -> ScreenHandlerType.GENERIC_9X5;
+                default -> ScreenHandlerType.GENERIC_9X6;
+            };
+        }
+    }
+
+    @Override
+    public boolean hasPermission(@NotNull String node) {
+        final boolean requiresOp = Boolean.TRUE.equals(
+                ((FabricHuskSync) plugin).getPermissions().getOrDefault(node, true)
+        );
+        return Permissions.check(player, node, !requiresOp || player.hasPermissionLevel(3));
+    }
+
+    @Override
+    public boolean isDead() {
+        return player.getHealth() <= 0.0f;
+    }
+
+    @Override
+    public boolean isLocked() {
+        return plugin.getLockedPlayers().contains(player.getUuid());
+    }
+
+    @Override
+    public boolean isNpc() {
+        return false;
+    }
+
+    @Override
+    @NotNull
+    public ServerPlayerEntity getPlayer() {
+        return player;
+    }
+
+    @NotNull
+    @Override
+    @ApiStatus.Internal
+    public HuskSync getPlugin() {
+        return plugin;
+    }
+}

fabric/src/main/java/net/william278/husksync/util/FabricKeyedAdapter.java

@@ -0,0 +1,76 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.util;
+
+import net.minecraft.entity.EntityType;
+import net.minecraft.entity.attribute.EntityAttribute;
+import net.minecraft.entity.effect.StatusEffect;
+import net.minecraft.registry.Registries;
+import net.minecraft.registry.Registry;
+import net.minecraft.util.Identifier;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+// Utility class for adapting "Keyed" Minecraft objects
+public final class FabricKeyedAdapter {
+
+    @Nullable
+    public static EntityType<?> matchEntityType(@NotNull String key) {
+        return getRegistryValue(Registries.ENTITY_TYPE, key);
+    }
+
+    @Nullable
+    public static String getEntityTypeId(@NotNull EntityType<?> entityType) {
+        return getRegistryKey(Registries.ENTITY_TYPE, entityType);
+    }
+
+    @Nullable
+    public static EntityAttribute matchAttribute(@NotNull String key) {
+        return getRegistryValue(Registries.ATTRIBUTE, key);
+    }
+
+    @Nullable
+    public static String getAttributeId(@NotNull EntityAttribute attribute) {
+        return getRegistryKey(Registries.ATTRIBUTE, attribute);
+    }
+
+    @Nullable
+    public static StatusEffect matchEffectType(@NotNull String key) {
+        return getRegistryValue(Registries.STATUS_EFFECT, key);
+    }
+
+    @Nullable
+    public static String getEffectId(@NotNull StatusEffect effect) {
+        return getRegistryKey(Registries.STATUS_EFFECT, effect);
+    }
+
+    @Nullable
+    private static <T> T getRegistryValue(@NotNull Registry<T> registry, @NotNull String keyString) {
+        final Identifier key = Identifier.tryParse(keyString);
+        return key != null ? registry.get(key) : null;
+    }
+
+    @Nullable
+    private static <T> String getRegistryKey(@NotNull Registry<T> registry, @NotNull T value) {
+        final Identifier key = registry.getId(value);
+        return key != null ? key.toString() : null;
+    }
+
+}

fabric/src/main/java/net/william278/husksync/util/FabricTask.java

@@ -0,0 +1,137 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.util;
+
+import net.william278.husksync.FabricHuskSync;
+import net.william278.husksync.HuskSync;
+import net.william278.husksync.data.UserDataHolder;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.TimeUnit;
+
+public interface FabricTask extends Task {
+
+    class Sync extends Task.Sync implements FabricTask {
+
+        protected Sync(@NotNull HuskSync plugin, @NotNull Runnable runnable, long delayTicks) {
+            super(plugin, runnable, delayTicks);
+        }
+
+        @Override
+        public void cancel() {
+            super.cancel();
+        }
+
+        @Override
+        public void run() {
+            if (!cancelled) {
+                Executors.newSingleThreadScheduledExecutor().schedule(
+                        () -> ((FabricHuskSync) getPlugin()).getMinecraftServer().executeSync(runnable),
+                        delayTicks * 50,
+                        TimeUnit.MILLISECONDS
+                );
+            }
+        }
+    }
+
+    class Async extends Task.Async implements FabricTask {
+        private CompletableFuture<Void> task;
+
+        protected Async(@NotNull HuskSync plugin, @NotNull Runnable runnable, long delayTicks) {
+            super(plugin, runnable, delayTicks);
+        }
+
+        @Override
+        public void cancel() {
+            if (task != null && !cancelled) {
+                task.cancel(true);
+            }
+            super.cancel();
+        }
+
+        @Override
+        public void run() {
+            if (!cancelled) {
+                this.task = CompletableFuture.runAsync(runnable, ((FabricHuskSync) getPlugin()).getMinecraftServer());
+            }
+        }
+    }
+
+    class Repeating extends Task.Repeating implements FabricTask {
+
+        private ScheduledFuture<?> task;
+
+        protected Repeating(@NotNull HuskSync plugin, @NotNull Runnable runnable, long repeatingTicks) {
+            super(plugin, runnable, repeatingTicks);
+        }
+
+        @Override
+        public void cancel() {
+            if (task != null && !cancelled) {
+                task.cancel(true);
+            }
+            super.cancel();
+        }
+
+        @Override
+        public void run() {
+            if (!cancelled) {
+                this.task = Executors.newSingleThreadScheduledExecutor().scheduleAtFixedRate(
+                        runnable,
+                        0,
+                        repeatingTicks * 50,
+                        TimeUnit.MILLISECONDS
+                );
+            }
+        }
+    }
+
+    interface Supplier extends Task.Supplier {
+
+        @NotNull
+        @Override
+        default Task.Sync getSyncTask(@NotNull Runnable runnable, @Nullable UserDataHolder user, long delayTicks) {
+            return new Sync(getPlugin(), runnable, delayTicks);
+        }
+
+        @NotNull
+        @Override
+        default Task.Async getAsyncTask(@NotNull Runnable runnable, long delayTicks) {
+            return new Async(getPlugin(), runnable, delayTicks);
+        }
+
+        @NotNull
+        @Override
+        default Task.Repeating getRepeatingTask(@NotNull Runnable runnable, long repeatingTicks) {
+            return new Repeating(getPlugin(), runnable, repeatingTicks);
+        }
+
+        @Override
+        default void cancelTasks() {
+            // Do nothing
+        }
+
+    }
+
+}

fabric/src/main/resources/fabric.mod.json

@@ -0,0 +1,55 @@
+{
+  "schemaVersion": 1,
+  "id": "husksync",
+  "version": "${version}",
+  "name": "husksync",
+  "icon": "assets/husksync/icon.png",
+  "description": "${description}",
+  "authors": [
+    {
+      "name": "William278",
+      "contact": {
+        "sources": "https://github.com/WiIIiam278",
+        "homepage": "https://william278.net"
+      }
+    },
+    {
+      "name": "hanbings",
+      "contact": {
+        "sources": "https://github.com/hanbings"
+      }
+    },
+    {
+      "name": "Stampede2011",
+      "contact": {
+        "sources": "https://github.com/Stampede2011"
+      }
+    }
+  ],
+  "license": "Apache-2.0",
+  "contact": {
+    "homepage": "https://william278.net/project/husksync",
+    "repo": "https://github.com/WiIIiam278/HuskSync",
+    "issues": "https://github.com/WiIIiam278/HuskSync/issues"
+  },
+  "environment": "server",
+  "entrypoints": {
+    "server": [
+      "net.william278.husksync.FabricHuskSync"
+    ]
+  },
+  "depends": {
+    "fabricloader": ">=${fabric_loader_version}",
+    "minecraft": ">=${fabric_minecraft_version}",
+    "fabric-api": "*"
+  },
+  "suggests": {
+    "plan": "*"
+  },
+  "mixins": [
+    "husksync.mixins.json"
+  ],
+  "custom": {
+    "modmenu:api": true
+  }
+}

fabric/src/main/resources/husksync.mixins.json

@@ -0,0 +1,17 @@
+{
+  "required": true,
+  "minVersion": "0.8",
+  "package": "net.william278.husksync.mixins",
+  "compatibilityLevel": "JAVA_17",
+  "server": [
+    "ItemEntityMixin",
+    "PlayerEntityMixin",
+    "ServerPlayerEntityMixin",
+    "ServerPlayNetworkHandlerMixin",
+    "ServerWorldMixin"
+  ],
+  "client": [],
+  "injectors": {
+    "defaultRequire": 1
+  }
+}

gradle.properties

@@ -3,13 +3,21 @@ org.gradle.jvmargs='-Dfile.encoding=UTF-8'
 org.gradle.daemon=true
 javaVersion=17
 
-plugin_version=3.5.1
+plugin_version=3.6.5
 plugin_archive=husksync
 plugin_description=A modern, cross-server player data synchronization system
 
-jedis_version=5.1.2
-mysql_driver_version=8.3.0
-mariadb_driver_version=3.3.3
+jedis_version=5.1.3
+mysql_driver_version=8.4.0
+mariadb_driver_version=3.4.0
 postgres_driver_version=42.7.3
-mongodb_driver_version=5.0.1
+mongodb_driver_version=5.1.0
 snappy_version=1.1.10.5
+
+fabric_minecraft_version=1.20.1
+fabric_loader_version=0.15.11
+fabric_yarn_mappings=1.20.1+build.10
+fabric_api_version=0.92.2+1.20.1
+adventure_platform_fabric_version=5.9.0
+fabric_permissions_api_version=0.2-SNAPSHOT
+sgui_version=1.2.2+1.20

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,7 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.0.2-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.8-bin.zip
 networkTimeout=10000
+validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

gradlew

@@ -83,10 +83,8 @@ done
 # This is normally unused
 # shellcheck disable=SC2034
 APP_BASE_NAME=${0##*/}
-APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
-
-# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
+APP_HOME=$( cd "${APP_HOME:-./}" > /dev/null && pwd -P ) || exit
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD=maximum
@@ -133,10 +131,13 @@ location of your Java installation."
     fi
 else
     JAVACMD=java
-    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+    if ! command -v java >/dev/null 2>&1
+    then
+        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
 
 Please set the JAVA_HOME variable in your environment to match the
 location of your Java installation."
+    fi
 fi
 
 # Increase the maximum file descriptors if we can.
@@ -144,7 +145,7 @@ if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
     case $MAX_FD in #(
       max*)
         # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
-        # shellcheck disable=SC3045
+        # shellcheck disable=SC2039,SC3045
         MAX_FD=$( ulimit -H -n ) ||
             warn "Could not query maximum file descriptor limit"
     esac
@@ -152,7 +153,7 @@ if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
       '' | soft) :;; #(
       *)
         # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
-        # shellcheck disable=SC3045
+        # shellcheck disable=SC2039,SC3045
         ulimit -n "$MAX_FD" ||
             warn "Could not set maximum file descriptor limit to $MAX_FD"
     esac
@@ -197,11 +198,15 @@ if "$cygwin" || "$msys" ; then
     done
 fi
 
-# Collect all arguments for the java command;
-#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
-#     shell script including quotes and variable substitutions, so put them in
-#     double quotes to make sure that they get re-expanded; and
-#   * put everything else in single quotes, so that it's not re-expanded.
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Collect all arguments for the java command:
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#     and any embedded shellness will be escaped.
+#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
+#     treated as '${Hostname}' itself on the command line.
 
 set -- \
         "-Dorg.gradle.appname=$APP_BASE_NAME" \