subprojects part 2

.github/FUNDING.yml

@@ -1 +1 @@
-custom: ['https://viaversion.com/donate', 'https://viaversion.com/backwards', 'https://viaversion.com/rewind', 'https://creeper123123321.keybase.pub/#donate']
+custom: ['https://viaversion.com/donate', 'https://viaversion.com/backwards', 'https://viaversion.com/rewind', 'https://creeper123123321.github.io/#donate']

.github/workflows/build.yml

@@ -18,7 +18,7 @@ jobs:
           java-version: 11
       - name: build
         env:
-          curse_api_key: ${{ secrets.CREEPER_CF }}
+          CURSEFORGE_API_KEY: ${{ secrets.CREEPER_CF }}
         run: ./gradlew
       - name: capture build artifacts
         uses: actions/upload-artifact@v2

build.gradle

@@ -16,7 +16,6 @@ class Globals {
 version = Globals.baseVersion + "+" + (ENV.GITHUB_RUN_NUMBER ? "" : "local-") + getBranch()
 logger.lifecycle("Building ViaFabric: " + version)
 
-import org.apache.commons.codec.digest.DigestUtils
 import net.fabricmc.loom.task.RunClientTask
 import net.fabricmc.loom.task.RunServerTask
 
@@ -118,13 +117,13 @@ allprojects {
     }
 
     jar {
-        classifier = "dev"
+        archiveClassifier = "dev"
     }
 
     afterEvaluate {
         remapJar {
             input = file("${project.buildDir}/libs/$archivesBaseName-${version}-dev.jar")
-            archiveName = "${archivesBaseName}-${version}.jar"
+            archiveFileName = "${archivesBaseName}-${version}.jar"
         }
 
         artifacts {
@@ -220,7 +219,7 @@ subprojects {
 task remapMavenJar(type: net.fabricmc.loom.task.RemapJarTask, dependsOn: jar) {
     afterEvaluate {
         input = file("${project.buildDir}/libs/${archivesBaseName}-${version}-dev.jar")
-        archiveName = "${archivesBaseName}-${version}-maven.jar"
+        archiveFileName = "${archivesBaseName}-${version}-maven.jar"
         addNestedDependencies = false
     }
 }
@@ -279,6 +278,10 @@ dependencies {
     mappings("net.fabricmc:yarn:1.8.9+build.202103291533:v2")
     modCompile("net.fabricmc:fabric-loader:0.10.5+build.213")
 
+    include("com.viaversion:viaversion:4.0.0-21w17a")
+    include("org.yaml:snakeyaml:1.28")
+    include("io.github.cottonmc:cotton-client-commands:1.0.0+1.15.2")
+
     afterEvaluate {
         subprojects.each {
             compile project(path: ":${it.name}", configuration: "dev")
@@ -298,11 +301,16 @@ curseforge {
         id = "391298"
         changelog = "A changelog can be found at https://github.com/ViaVersion/ViaFabric/commits"
         releaseType = "alpha"
-        addGameVersion "1.17"
+        Arrays.<String> asList("1.17", "1.16.5", "1.15.2", "1.14.4", "1.8.9", "Java 8", "Java 9", "Java 10", "Fabric")
-        addGameVersion "Fabric"
+                .forEach { ver -> addGameVersion(ver) }
 
         mainArtifact(file("${project.buildDir}/libs/${archivesBaseName}-${version}.jar")) {
             displayName = "[${getBranch()}] ViaFabric $Globals.baseVersion"
+            relations {
+                requiredDependency("fabric-api")
+                requiredDependency("legacy-fabric-api")
+                embeddedLibrary("cotton-client-commands")
+            }
         }
 
         afterEvaluate {
@@ -314,3 +322,9 @@ curseforge {
         forgeGradleIntegration = false
     }
 }
+
+if (getBranch() == "master" && ENV.CURSEFORGE_API_KEY && !ENV.CURSEFORGE_API_KEY.isEmpty()) {
+    defaultTasks("clean", "build", "curseforge")
+} else {
+    defaultTasks("clean", "build")
+}

settings.gradle

@@ -12,4 +12,6 @@ rootProject.name = "viafabric"
 
 include "viafabric-mc18"
 include "viafabric-mc114"
+include "viafabric-mc115"
+include "viafabric-mc116"
 include "viafabric-mc117"

viafabric-mc114/src/main/resources/fabric.mod.json

@@ -1,6 +1,6 @@
 {
   "schemaVersion": 1,
-  "id": "viafabric-impl",
+  "id": "viafabric-mc114",
   "name": "ViaFabric",
   "version": "@version@",
   "description": "@description@",

viafabric-mc114/src/main/resources/mixins.viafabric.address.json

@@ -1,13 +1,12 @@
 {
   "required": true,
   "compatibilityLevel": "JAVA_8",
-  "package": "com.viaversion.fabric.mc114.mixin.address",
   "mixins": [
   ],
   "client": [
-    "client.MixinConnectScreenThread",
+    "com.viaversion.fabric.mc114.mixin.address.client.MixinConnectScreenThread",
-    "client.MixinServerAddress",
+    "com.viaversion.fabric.mc114.mixin.address.client.MixinServerAddress",
-    "client.MixinServerPinger"
+    "com.viaversion.fabric.mc114.mixin.address.client.MixinServerPinger"
   ],
   "injectors": {
     "defaultRequire": 1

viafabric-mc114/src/main/resources/mixins.viafabric.debug.json

@@ -1,12 +1,11 @@
 {
   "required": true,
   "compatibilityLevel": "JAVA_8",
-  "package": "com.viaversion.fabric.mc114.mixin.debug",
   "mixins": [
   ],
   "client": [
-    "client.MixinClientConnectionAccessor",
+    "com.viaversion.fabric.mc114.mixin.debug.client.MixinClientConnectionAccessor",
-    "client.MixinDebugHud"
+    "com.viaversion.fabric.mc114.mixin.debug.client.MixinDebugHud"
   ],
   "injectors": {
     "defaultRequire": 0

viafabric-mc114/src/main/resources/mixins.viafabric.gui.json

@@ -1,11 +1,10 @@
 {
   "required": true,
   "compatibilityLevel": "JAVA_8",
-  "package": "com.viaversion.fabric.mc114.mixin.gui",
   "mixins": [
   ],
   "client": [
-    "client.MixinMultiplayerScreen"
+    "com.viaversion.fabric.mc114.mixin.gui.client.MixinMultiplayerScreen"
   ],
   "injectors": {
     "defaultRequire": 0

viafabric-mc114/src/main/resources/mixins.viafabric.pipeline.json

@@ -1,13 +1,12 @@
 {
   "required": true,
   "compatibilityLevel": "JAVA_8",
-  "package": "com.viaversion.fabric.mc114.mixin.pipeline",
   "mixins": [
-    "MixinClientConnection",
+    "com.viaversion.fabric.mc114.mixin.pipeline.MixinClientConnection",
-    "MixinServerNetworkIoChInit"
+    "com.viaversion.fabric.mc114.mixin.pipeline.MixinServerNetworkIoChInit"
   ],
   "client": [
-    "client.MixinClientConnectionChInit"
+    "com.viaversion.fabric.mc114.mixin.pipeline.client.MixinClientConnectionChInit"
   ],
   "injectors": {
     "defaultRequire": 1

viafabric-mc115/build.gradle.kts

@@ -1,11 +1,10 @@
 version = rootProject.version
 
 dependencies {
-    minecraft("com.mojang:minecraft:1.14.4")
+    minecraft("com.mojang:minecraft:1.15.2")
-    mappings("net.fabricmc:yarn:1.14.4+build.16:v2")
+    mappings("net.fabricmc:yarn:1.15.2+build.17:v2")
-    modImplementation("net.fabricmc:fabric-loader:0.8.2+build.194")
+    modImplementation("net.fabricmc:fabric-loader:0.9.3+build.207")
 
-    modImplementation("net.fabricmc.fabric-api:fabric-api:0.13.1+build.257-1.14")
+    modImplementation("net.fabricmc.fabric-api:fabric-api:0.19.0+build.325-1.15")
-    modImplementation("io.github.prospector:modmenu:1.7.16.1.14.4+build.128")
+    modImplementation("io.github.prospector:modmenu:1.10.2+build.32")
-    modImplementation("io.github.cottonmc:cotton-client-commands:1.0.0+1.15.2")
 }

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/ViaFabric.java

@@ -0,0 +1,110 @@
+package com.viaversion.fabric.mc115;
+
+import com.viaversion.fabric.mc115.commands.VRCommandHandler;
+import com.viaversion.fabric.mc115.config.VRConfig;
+import com.viaversion.fabric.mc115.platform.VRInjector;
+import com.viaversion.fabric.mc115.platform.VRLoader;
+import com.viaversion.fabric.mc115.platform.VRPlatform;
+import com.viaversion.fabric.mc115.protocol.ViaFabricHostnameProtocol;
+import com.viaversion.fabric.mc115.util.JLoggerToLog4j;
+import com.google.common.collect.Range;
+import com.google.common.util.concurrent.ThreadFactoryBuilder;
+import com.mojang.brigadier.arguments.StringArgumentType;
+import com.mojang.brigadier.builder.LiteralArgumentBuilder;
+import com.mojang.brigadier.builder.RequiredArgumentBuilder;
+import io.netty.channel.DefaultEventLoop;
+import io.netty.channel.EventLoop;
+import net.fabricmc.api.ModInitializer;
+import net.fabricmc.fabric.api.command.v1.CommandRegistrationCallback;
+import net.fabricmc.fabric.api.registry.CommandRegistry;
+import net.fabricmc.loader.api.FabricLoader;
+import net.minecraft.server.command.CommandSource;
+import org.apache.logging.log4j.LogManager;
+import com.viaversion.viaversion.ViaManagerImpl;
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.data.MappingDataLoader;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ThreadFactory;
+import java.util.logging.Logger;
+
+public class ViaFabric implements ModInitializer {
+    public static final Logger JLOGGER = new JLoggerToLog4j(LogManager.getLogger("ViaFabric"));
+    public static final ExecutorService ASYNC_EXECUTOR;
+    public static final EventLoop EVENT_LOOP;
+    public static CompletableFuture<Void> INIT_FUTURE = new CompletableFuture<>();
+    public static VRConfig config;
+
+    static {
+        ThreadFactory factory = new ThreadFactoryBuilder().setDaemon(true).setNameFormat("ViaFabric-%d").build();
+        ASYNC_EXECUTOR = Executors.newFixedThreadPool(8, factory);
+        EVENT_LOOP = new DefaultEventLoop(factory);
+        EVENT_LOOP.submit(INIT_FUTURE::join); // https://github.com/ViaVersion/ViaFabric/issues/53 ugly workaround code but works tm
+    }
+
+    public static String getVersion() {
+        return FabricLoader.getInstance().getModContainer("viafabric")
+                .get().getMetadata().getVersion().getFriendlyString();
+    }
+
+    public static <S extends CommandSource> LiteralArgumentBuilder<S> command(String commandName) {
+        return LiteralArgumentBuilder.<S>literal(commandName)
+                .then(
+                        RequiredArgumentBuilder
+                                .<S, String>argument("args", StringArgumentType.greedyString())
+                                .executes(((VRCommandHandler) Via.getManager().getCommandHandler())::execute)
+                                .suggests(((VRCommandHandler) Via.getManager().getCommandHandler())::suggestion)
+                )
+                .executes(((VRCommandHandler) Via.getManager().getCommandHandler())::execute);
+    }
+
+    @Override
+    public void onInitialize() {
+        Via.init(ViaManagerImpl.builder()
+                .injector(new VRInjector())
+                .loader(new VRLoader())
+                .commandHandler(new VRCommandHandler())
+                .platform(new VRPlatform()).build());
+
+        FabricLoader.getInstance().getModContainer("viabackwards").ifPresent(mod -> MappingDataLoader.enableMappingsCache());
+
+        ((ViaManagerImpl) Via.getManager()).init();
+
+        Via.getManager().getProtocolManager().registerBaseProtocol(ViaFabricHostnameProtocol.INSTANCE, Range.lessThan(Integer.MIN_VALUE));
+        ProtocolVersion.register(-2, "AUTO");
+
+        FabricLoader.getInstance().getEntrypoints("viafabric:via_api_initialized", Runnable.class).forEach(Runnable::run);
+
+        try {
+            registerCommandsV1();
+        } catch (NoClassDefFoundError ignored) {
+            try {
+                registerCommandsV0();
+                JLOGGER.info("Using Fabric Commands V0");
+            } catch (NoClassDefFoundError ignored2) {
+                JLOGGER.info("Couldn't register command as Fabric Commands isn't installed");
+            }
+        }
+
+        config = new VRConfig(FabricLoader.getInstance().getConfigDir().resolve("ViaFabric")
+                .resolve("viafabric.yml").toFile());
+
+        INIT_FUTURE.complete(null);
+    }
+
+    private void registerCommandsV1() {
+        CommandRegistrationCallback.EVENT.register((dispatcher, dedicated) -> dispatcher.register(command("viaversion")));
+        CommandRegistrationCallback.EVENT.register((dispatcher, dedicated) -> dispatcher.register(command("viaver")));
+        CommandRegistrationCallback.EVENT.register((dispatcher, dedicated) -> dispatcher.register(command("vvfabric")));
+    }
+
+    @SuppressWarnings("deprecation")
+    private void registerCommandsV0() {
+        CommandRegistry.INSTANCE.register(false, dispatcher -> dispatcher.register(command("viaversion")));
+        CommandRegistry.INSTANCE.register(false, dispatcher -> dispatcher.register(command("viaver")));
+        CommandRegistry.INSTANCE.register(false, dispatcher -> dispatcher.register(command("vvfabric")));
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/ViaFabricAddress.java

@@ -0,0 +1,77 @@
+package com.viaversion.fabric.mc115;
+
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+
+import java.util.Locale;
+
+public class ViaFabricAddress {
+    public int protocol = 0;
+    public String viaSuffix = null;
+    public String realAddress = null;
+
+    public ViaFabricAddress parse(String address) {
+        if (address == null) return null;
+        String[] parts = address.split("\\.");
+
+        boolean foundDomain = false;
+        boolean foundOptions = false;
+
+        StringBuilder ourParts = new StringBuilder();
+        StringBuilder realAddrBuilder = new StringBuilder();
+
+        for (int i = parts.length - 1; i >= 0; i--) {
+            String part = parts[i];
+            boolean realAddrPart = false;
+            if (foundDomain) {
+                if (!foundOptions) {
+                    if (part.startsWith("_")) {
+                        String arg = part.substring(2);
+                        if (part.toLowerCase(Locale.ROOT).startsWith("_v")) {
+                            try {
+                                protocol = Integer.parseInt(arg);
+                            } catch (NumberFormatException e) {
+                                ProtocolVersion closest = ProtocolVersion.getClosest(arg.replace("_", "."));
+                                if (closest != null) {
+                                    protocol = closest.getVersion();
+                                }
+                            }
+                        }
+                    } else {
+                        foundOptions = true;
+                    }
+                }
+                if (foundOptions) {
+                    realAddrPart = true;
+                }
+            } else if (part.equalsIgnoreCase("viafabric")) {
+                foundDomain = true;
+            }
+            if (realAddrPart) {
+                realAddrBuilder.insert(0, part + ".");
+            } else {
+                ourParts.insert(0, part + ".");
+            }
+        }
+
+        String realAddr = realAddrBuilder.toString().replaceAll("\\.$", "");
+        String suffix = ourParts.toString().replaceAll("\\.$", "");
+
+        if (realAddr.isEmpty()) {
+            this.realAddress = address;
+        } else {
+            this.realAddress = realAddr;
+            this.viaSuffix = suffix;
+        }
+
+        return this;
+    }
+
+    @Override
+    public String toString() {
+        return "ViaFabricAddress{" +
+                "protocol=" + protocol +
+                ", viaSuffix='" + viaSuffix + '\'' +
+                ", realAddress='" + realAddress + '\'' +
+                '}';
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/commands/NMSCommandSender.java

@@ -0,0 +1,61 @@
+package com.viaversion.fabric.mc115.commands;
+
+import io.github.cottonmc.clientcommands.CottonClientCommandSource;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.entity.Entity;
+import net.minecraft.server.command.CommandSource;
+import net.minecraft.server.command.ServerCommandSource;
+import net.minecraft.text.Text;
+import com.viaversion.viaversion.api.command.ViaCommandSender;
+import com.viaversion.viaversion.libs.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
+import com.viaversion.viaversion.libs.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
+
+import java.util.UUID;
+
+public class NMSCommandSender implements ViaCommandSender {
+    private final CommandSource source;
+
+    public NMSCommandSender(CommandSource source) {
+        this.source = source;
+    }
+
+    @Override
+    public boolean hasPermission(String s) {
+        // https://gaming.stackexchange.com/questions/138602/what-does-op-permission-level-do
+        return source.hasPermissionLevel(3);
+    }
+
+    @Override
+    public void sendMessage(String s) {
+        if (source instanceof ServerCommandSource) {
+            ((ServerCommandSource) source).sendFeedback(Text.Serializer.fromJson(legacyToJson(s)), false);
+        } else if (source instanceof CottonClientCommandSource) {
+            ((CottonClientCommandSource) source).sendFeedback(Text.Serializer.fromJson(legacyToJson(s)), false);
+        }
+    }
+
+    private String legacyToJson(String legacy) {
+        return GsonComponentSerializer.gson().serialize(LegacyComponentSerializer.legacySection().deserialize(legacy));
+    }
+
+    @Override
+    public UUID getUUID() {
+        if (source instanceof ServerCommandSource) {
+            Entity entity = ((ServerCommandSource) source).getEntity();
+            if (entity != null) return entity.getUuid();
+        } else if (source instanceof CottonClientCommandSource) {
+            return MinecraftClient.getInstance().player.getUuid();
+        }
+        return UUID.fromString(getName());
+    }
+
+    @Override
+    public String getName() {
+        if (source instanceof ServerCommandSource) {
+            return ((ServerCommandSource) source).getName();
+        } else if (source instanceof CottonClientCommandSource) {
+            return MinecraftClient.getInstance().player.getEntityName();
+        }
+        return "?";
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/commands/UserCommandSender.java

@@ -0,0 +1,35 @@
+package com.viaversion.fabric.mc115.commands;
+
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.command.ViaCommandSender;
+import com.viaversion.viaversion.api.connection.UserConnection;
+
+import java.util.UUID;
+
+public class UserCommandSender implements ViaCommandSender {
+    private UserConnection con;
+
+    public UserCommandSender(UserConnection con) {
+        this.con = con;
+    }
+
+    @Override
+    public boolean hasPermission(String s) {
+        return false;
+    }
+
+    @Override
+    public void sendMessage(String s) {
+        Via.getPlatform().sendMessage(getUUID(), s);
+    }
+
+    @Override
+    public UUID getUUID() {
+        return con.getProtocolInfo().getUuid();
+    }
+
+    @Override
+    public String getName() {
+        return con.getProtocolInfo().getUsername();
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/commands/VRClientCommands.java

@@ -0,0 +1,13 @@
+package com.viaversion.fabric.mc115.commands;
+
+import com.viaversion.fabric.mc115.ViaFabric;
+import com.mojang.brigadier.CommandDispatcher;
+import io.github.cottonmc.clientcommands.ClientCommandPlugin;
+import io.github.cottonmc.clientcommands.CottonClientCommandSource;
+
+public class VRClientCommands implements ClientCommandPlugin {
+    @Override
+    public void registerCommands(CommandDispatcher<CottonClientCommandSource> commandDispatcher) {
+        commandDispatcher.register(ViaFabric.command("viafabricclient"));
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/commands/VRCommandHandler.java

@@ -0,0 +1,55 @@
+package com.viaversion.fabric.mc115.commands;
+
+import com.viaversion.fabric.mc115.commands.subs.LeakDetectSubCommand;
+import com.mojang.brigadier.arguments.StringArgumentType;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.suggestion.Suggestions;
+import com.mojang.brigadier.suggestion.SuggestionsBuilder;
+import net.minecraft.server.command.CommandSource;
+import com.viaversion.viaversion.commands.ViaCommandHandler;
+
+import java.util.concurrent.CompletableFuture;
+
+public class VRCommandHandler extends ViaCommandHandler {
+    {
+        try {
+            registerSubCommand(new LeakDetectSubCommand());
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+
+    public int execute(CommandContext<? extends CommandSource> ctx) {
+        String[] args = new String[0];
+        try {
+            args = StringArgumentType.getString(ctx, "args").split(" ");
+        } catch (IllegalArgumentException ignored) {
+        }
+        onCommand(
+                new NMSCommandSender(ctx.getSource()),
+                args
+        );
+        return 1;
+    }
+
+    public CompletableFuture<Suggestions> suggestion(CommandContext<? extends CommandSource> ctx, SuggestionsBuilder builder) {
+        String[] args;
+        try {
+            args = StringArgumentType.getString(ctx, "args").split(" ", -1);
+        } catch (IllegalArgumentException ignored) {
+            args = new String[]{""};
+        }
+        String[] pref = args.clone();
+        pref[pref.length - 1] = "";
+        String prefix = String.join(" ", pref);
+        onTabComplete(new NMSCommandSender(ctx.getSource()), args)
+                .stream()
+                .map(it -> {
+                    SuggestionsBuilder b = new SuggestionsBuilder(builder.getInput(), prefix.length() + builder.getStart());
+                    b.suggest(it);
+                    return b;
+                })
+                .forEach(builder::add);
+        return builder.buildFuture();
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/commands/subs/LeakDetectSubCommand.java

@@ -0,0 +1,48 @@
+package com.viaversion.fabric.mc115.commands.subs;
+
+import io.netty.util.ResourceLeakDetector;
+import com.viaversion.viaversion.api.command.ViaCommandSender;
+import com.viaversion.viaversion.api.command.ViaSubCommand;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class LeakDetectSubCommand extends ViaSubCommand {
+    @Override
+    public String name() {
+        return "leakdetect";
+    }
+
+    @Override
+    public String description() {
+        return "Sets ResourceLeakDetector level";
+    }
+
+    @Override
+    public boolean execute(ViaCommandSender viaCommandSender, String[] strings) {
+        if (strings.length == 1) {
+            try {
+                ResourceLeakDetector.Level level = ResourceLeakDetector.Level.valueOf(strings[0]);
+                ResourceLeakDetector.setLevel(level);
+                viaCommandSender.sendMessage("Set leak detector level to " + level);
+            } catch (IllegalArgumentException e) {
+                viaCommandSender.sendMessage("Invalid level (" + Arrays.toString(ResourceLeakDetector.Level.values()) + ")");
+            }
+        } else {
+            viaCommandSender.sendMessage("Current leak detection level is " + ResourceLeakDetector.getLevel());
+        }
+        return true;
+    }
+
+    @Override
+    public List<String> onTabComplete(ViaCommandSender sender, String[] args) {
+        if (args.length == 1) {
+            return Arrays.stream(ResourceLeakDetector.Level.values())
+                    .map(Enum::name)
+                    .filter(it -> it.startsWith(args[0]))
+                    .collect(Collectors.toList());
+        }
+        return super.onTabComplete(sender, args);
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/config/VRConfig.java

@@ -0,0 +1,68 @@
+package com.viaversion.fabric.mc115.config;
+
+import com.viaversion.viaversion.util.Config;
+
+import java.io.File;
+import java.net.URL;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+
+public class VRConfig extends Config {
+    public static final String ENABLE_CLIENT_SIDE = "enable-client-side";
+    public static final String CLIENT_SIDE_VERSION = "client-side-version";
+    public static final String CLIENT_SIDE_FORCE_DISABLE = "client-side-force-disable";
+    public static final String HIDE_BUTTON = "hide-button";
+
+    public VRConfig(File configFile) {
+        super(configFile);
+        reloadConfig();
+    }
+
+    @Override
+    public URL getDefaultConfigURL() {
+        return getClass().getClassLoader().getResource("assets/viafabric/config.yml");
+    }
+
+    @Override
+    protected void handleConfig(Map<String, Object> map) {
+    }
+
+    @Override
+    public List<String> getUnsupportedOptions() {
+        return Collections.emptyList();
+    }
+
+    public boolean isClientSideEnabled() {
+        return getBoolean(ENABLE_CLIENT_SIDE, false);
+    }
+
+    public void setClientSideEnabled(boolean val) {
+        set(ENABLE_CLIENT_SIDE, val);
+    }
+
+    public int getClientSideVersion() {
+        return getInt(CLIENT_SIDE_VERSION, -1);
+    }
+
+    public void setClientSideVersion(int val) {
+        set(CLIENT_SIDE_VERSION, val);
+    }
+
+    public Collection<?> getClientSideForceDisable() {
+        return (List<?>) get(CLIENT_SIDE_FORCE_DISABLE, List.class, Collections.emptyList());
+    }
+
+    public void setHideButton(boolean val) {
+        set(HIDE_BUTTON, val);
+    }
+
+    public boolean isHideButton() {
+        return getBoolean(HIDE_BUTTON, false);
+    }
+
+    public boolean isForcedDisable(String line) {
+        return getClientSideForceDisable().contains(line);
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/gui/ModMenuConfig.java

@@ -0,0 +1,16 @@
+package com.viaversion.fabric.mc115.gui;
+
+import io.github.prospector.modmenu.api.ConfigScreenFactory;
+import io.github.prospector.modmenu.api.ModMenuApi;
+
+public class ModMenuConfig implements ModMenuApi {
+    @Override
+    public String getModId() {
+        return "viafabric";
+    }
+
+    @Override
+    public ConfigScreenFactory<?> getModConfigScreenFactory() {
+        return ViaConfigScreen::new;
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/gui/ViaConfigScreen.java

@@ -0,0 +1,169 @@
+package com.viaversion.fabric.mc115.gui;
+
+import com.viaversion.fabric.mc115.ViaFabric;
+import com.viaversion.fabric.mc115.util.ProtocolUtils;
+import com.viaversion.viaversion.api.Via;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.api.Environment;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.gui.screen.ConfirmScreen;
+import net.minecraft.client.gui.screen.Screen;
+import net.minecraft.client.gui.widget.ButtonWidget;
+import net.minecraft.client.gui.widget.TextFieldWidget;
+import net.minecraft.text.TranslatableText;
+
+import java.util.concurrent.CompletableFuture;
+
+@Environment(EnvType.CLIENT)
+public class ViaConfigScreen extends Screen {
+    private static CompletableFuture<Void> latestProtocolSave;
+    private final Screen parent;
+    private TextFieldWidget protocolVersion;
+
+    public ViaConfigScreen(Screen parent) {
+        super(new TranslatableText("gui.viafabric_config.title"));
+        this.parent = parent;
+    }
+
+    private static int getProtocolTextColor(boolean valid, boolean supported) {
+
+        if (!valid) {
+            return 0xff0000; // Red
+        } else if (!supported) {
+            return 0xFFA500; // Orange
+        }
+        return 0xE0E0E0; // Default
+    }
+
+    @Override
+    protected void init() {
+        int entries = 0;
+
+        this.addButton(new ButtonWidget(this.width / 2 - 155 + entries % 2 * 160,
+                this.height / 6 + 24 * (entries >> 1),
+                150,
+                20, getClientSideText().asString(), this::onClickClientSide));
+        entries++;
+
+        this.addButton(new ButtonWidget(this.width / 2 - 155 + entries % 2 * 160,
+                this.height / 6 + 24 * (entries >> 1),
+                150,
+                20, getHideViaButtonText().asString(), this::onHideViaButton));
+        entries++;
+
+        protocolVersion = new TextFieldWidget(this.font,
+                this.width / 2 - 155 + entries % 2 * 160,
+                this.height / 6 + 24 * (entries >> 1),
+                150,
+                20, new TranslatableText("gui.protocol_version_field.name").asString());
+        entries++;
+
+        protocolVersion.setTextPredicate(ProtocolUtils::isStartOfProtocolText);
+        protocolVersion.setChangedListener(this::onChangeVersionField);
+        int clientSideVersion = ViaFabric.config.getClientSideVersion();
+        protocolVersion.setText(ProtocolUtils.getProtocolName(clientSideVersion));
+
+        this.children.add(protocolVersion);
+
+        //noinspection ConstantConditions
+        if (entries % 2 == 1) {
+            entries++;
+        }
+
+        this.addButton(new ButtonWidget(this.width / 2 - 100, this.height / 6 + 24 * (entries >> 1), 200, 20, new TranslatableText("gui.done").asString(), (buttonWidget) -> MinecraftClient.getInstance().openScreen(this.parent)));
+    }
+
+    private void onChangeVersionField(String text) {
+        protocolVersion.setSuggestion(null);
+        int newVersion = ViaFabric.config.getClientSideVersion();
+
+        Integer parsed = ProtocolUtils.parseProtocolId(text);
+        boolean validProtocol;
+
+        if (parsed != null) {
+            newVersion = parsed;
+            validProtocol = true;
+        } else {
+            validProtocol = false;
+            String[] suggestions = ProtocolUtils.getProtocolSuggestions(text);
+            if (suggestions.length == 1) {
+                protocolVersion.setSuggestion(suggestions[0].substring(text.length()));
+            }
+        }
+
+        protocolVersion.setEditableColor(
+                getProtocolTextColor(ProtocolUtils.isSupported(newVersion, Via.getAPI().getServerVersion().lowestSupportedVersion()),
+                        validProtocol));
+
+        int finalNewVersion = newVersion;
+        if (latestProtocolSave == null) latestProtocolSave = CompletableFuture.completedFuture(null);
+        ViaFabric.config.setClientSideVersion(finalNewVersion);
+        latestProtocolSave = latestProtocolSave.thenRunAsync(ViaFabric.config::saveConfig, ViaFabric.ASYNC_EXECUTOR);
+    }
+
+    private void onClickClientSide(ButtonWidget widget) {
+        if (!ViaFabric.config.isClientSideEnabled()) {
+            MinecraftClient.getInstance().openScreen(new ConfirmScreen(
+                    answer -> {
+                        if (answer) {
+                            ViaFabric.config.setClientSideEnabled(true);
+                            ViaFabric.config.setClientSideVersion(-2); // AUTO
+                            ViaFabric.config.saveConfig();
+                            widget.setMessage(getClientSideText().asString());
+                        }
+                        MinecraftClient.getInstance().openScreen(this);
+                    },
+                    new TranslatableText("gui.enable_client_side.question"),
+                    new TranslatableText("gui.enable_client_side.warning"),
+                    new TranslatableText("gui.enable_client_side.enable").asString(),
+                    new TranslatableText("gui.cancel").asString()
+            ));
+        } else {
+            ViaFabric.config.setClientSideEnabled(false);
+            ViaFabric.config.saveConfig();
+        }
+        widget.setMessage(getClientSideText().asString());
+    }
+
+    @Override
+    public void removed() {
+        ViaFabric.config.saveConfig();
+    }
+
+    @Override
+    public void onClose() {
+        MinecraftClient.getInstance().openScreen(this.parent);
+    }
+
+    private TranslatableText getClientSideText() {
+        return ViaFabric.config.isClientSideEnabled() ?
+                new TranslatableText("gui.client_side.disable")
+                : new TranslatableText("gui.client_side.enable");
+    }
+
+    private TranslatableText getHideViaButtonText() {
+        return ViaFabric.config.isHideButton() ?
+                new TranslatableText("gui.hide_via_button.disable") : new TranslatableText("gui.hide_via_button.enable");
+    }
+
+    private void onHideViaButton(ButtonWidget widget) {
+        ViaFabric.config.setHideButton(!ViaFabric.config.isHideButton());
+        ViaFabric.config.saveConfig();
+        widget.setMessage(getHideViaButtonText().asString());
+    }
+
+    @Override
+    public void render(int mouseX, int mouseY, float delta) {
+        this.renderBackground();
+        drawCenteredString(this.font, this.title.asString(), this.width / 2, 20, 16777215);
+        super.render(mouseX, mouseY, delta);
+        protocolVersion.render(mouseX, mouseY, delta);
+    }
+
+    @Override
+    public void tick() {
+        super.tick();
+        protocolVersion.tick();
+    }
+}
+

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/handler/CommonTransformer.java

@@ -0,0 +1,38 @@
+package com.viaversion.fabric.mc115.handler;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandler;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.ByteToMessageDecoder;
+import io.netty.handler.codec.MessageToByteEncoder;
+import io.netty.handler.codec.MessageToMessageDecoder;
+import com.viaversion.viaversion.util.PipelineUtil;
+
+import java.lang.reflect.InvocationTargetException;
+
+public class CommonTransformer {
+    public static final String HANDLER_DECODER_NAME = "via-decoder";
+    public static final String HANDLER_ENCODER_NAME = "via-encoder";
+
+    public static void decompress(ChannelHandlerContext ctx, ByteBuf buf) throws InvocationTargetException {
+        ChannelHandler handler = ctx.pipeline().get("decompress");
+        ByteBuf decompressed = handler instanceof MessageToMessageDecoder
+                ? (ByteBuf) PipelineUtil.callDecode((MessageToMessageDecoder<?>) handler, ctx, buf).get(0)
+                : (ByteBuf) PipelineUtil.callDecode((ByteToMessageDecoder) handler, ctx, buf).get(0);
+        try {
+            buf.clear().writeBytes(decompressed);
+        } finally {
+            decompressed.release();
+        }
+    }
+
+    public static void compress(ChannelHandlerContext ctx, ByteBuf buf) throws Exception {
+        ByteBuf compressed = ctx.alloc().buffer();
+        try {
+            PipelineUtil.callEncode((MessageToByteEncoder<?>) ctx.pipeline().get("compress"), ctx, buf, compressed);
+            buf.clear().writeBytes(compressed);
+        } finally {
+            compressed.release();
+        }
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/handler/FabricDecodeHandler.java

@@ -0,0 +1,85 @@
+package com.viaversion.fabric.mc115.handler;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandler;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.MessageToMessageDecoder;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.exception.CancelCodecException;
+import com.viaversion.viaversion.exception.CancelDecoderException;
+import com.viaversion.viaversion.util.PipelineUtil;
+
+import java.lang.reflect.InvocationTargetException;
+import java.util.List;
+
+@ChannelHandler.Sharable
+public class FabricDecodeHandler extends MessageToMessageDecoder<ByteBuf> {
+    private final UserConnection info;
+    private boolean handledCompression;
+    private boolean skipDoubleTransform;
+
+    public FabricDecodeHandler(UserConnection info) {
+        this.info = info;
+    }
+
+    public UserConnection getInfo() {
+        return info;
+    }
+
+    // https://github.com/ViaVersion/ViaVersion/blob/master/velocity/src/main/java/us/myles/ViaVersion/velocity/handlers/VelocityDecodeHandler.java
+    @Override
+    protected void decode(ChannelHandlerContext ctx, ByteBuf bytebuf, List<Object> out) throws Exception {
+        if (skipDoubleTransform) {
+            skipDoubleTransform = false;
+            out.add(bytebuf.retain());
+            return;
+        }
+
+        if (!info.checkIncomingPacket()) throw CancelDecoderException.generate(null);
+        if (!info.shouldTransformPacket()) {
+            out.add(bytebuf.retain());
+            return;
+        }
+
+        ByteBuf transformedBuf = ctx.alloc().buffer().writeBytes(bytebuf);
+        try {
+            boolean needsCompress = handleCompressionOrder(ctx, transformedBuf);
+
+            info.transformIncoming(transformedBuf, CancelDecoderException::generate);
+
+            if (needsCompress) {
+                CommonTransformer.compress(ctx, transformedBuf);
+                skipDoubleTransform = true;
+            }
+            out.add(transformedBuf.retain());
+        } finally {
+            transformedBuf.release();
+        }
+    }
+
+    private boolean handleCompressionOrder(ChannelHandlerContext ctx, ByteBuf buf) throws InvocationTargetException {
+        if (handledCompression) return false;
+
+        int decoderIndex = ctx.pipeline().names().indexOf("decompress");
+        if (decoderIndex == -1) return false;
+        handledCompression = true;
+        if (decoderIndex > ctx.pipeline().names().indexOf("via-decoder")) {
+            // Need to decompress this packet due to bad order
+            CommonTransformer.decompress(ctx, buf);
+            ChannelHandler encoder = ctx.pipeline().get("via-encoder");
+            ChannelHandler decoder = ctx.pipeline().get("via-decoder");
+            ctx.pipeline().remove(encoder);
+            ctx.pipeline().remove(decoder);
+            ctx.pipeline().addAfter("compress", "via-encoder", encoder);
+            ctx.pipeline().addAfter("decompress", "via-decoder", decoder);
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+        if (PipelineUtil.containsCause(cause, CancelCodecException.class)) return;
+        super.exceptionCaught(ctx, cause);
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/handler/FabricEncodeHandler.java

@@ -0,0 +1,72 @@
+package com.viaversion.fabric.mc115.handler;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandler;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.MessageToMessageEncoder;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.exception.CancelCodecException;
+import com.viaversion.viaversion.exception.CancelEncoderException;
+import com.viaversion.viaversion.util.PipelineUtil;
+
+import java.lang.reflect.InvocationTargetException;
+import java.util.List;
+
+@ChannelHandler.Sharable
+public class FabricEncodeHandler extends MessageToMessageEncoder<ByteBuf> {
+    private final UserConnection info;
+    private boolean handledCompression;
+
+    public FabricEncodeHandler(UserConnection info) {
+        this.info = info;
+    }
+
+    @Override
+    protected void encode(final ChannelHandlerContext ctx, ByteBuf bytebuf, List<Object> out) throws Exception {
+        if (!info.checkOutgoingPacket()) throw CancelEncoderException.generate(null);
+        if (!info.shouldTransformPacket()) {
+            out.add(bytebuf.retain());
+            return;
+        }
+
+        ByteBuf transformedBuf = ctx.alloc().buffer().writeBytes(bytebuf);
+        try {
+            boolean needsCompress = handleCompressionOrder(ctx, transformedBuf);
+
+            info.transformOutgoing(transformedBuf, CancelEncoderException::generate);
+
+            if (needsCompress) {
+                CommonTransformer.compress(ctx, transformedBuf);
+            }
+            out.add(transformedBuf.retain());
+        } finally {
+            transformedBuf.release();
+        }
+    }
+
+    private boolean handleCompressionOrder(ChannelHandlerContext ctx, ByteBuf buf) throws InvocationTargetException {
+        if (handledCompression) return false;
+
+        int encoderIndex = ctx.pipeline().names().indexOf("compress");
+        if (encoderIndex == -1) return false;
+        handledCompression = true;
+        if (encoderIndex > ctx.pipeline().names().indexOf("via-encoder")) {
+            // Need to decompress this packet due to bad order
+            CommonTransformer.decompress(ctx, buf);
+            ChannelHandler encoder = ctx.pipeline().get("via-encoder");
+            ChannelHandler decoder = ctx.pipeline().get("via-decoder");
+            ctx.pipeline().remove(encoder);
+            ctx.pipeline().remove(decoder);
+            ctx.pipeline().addAfter("compress", "via-encoder", encoder);
+            ctx.pipeline().addAfter("decompress", "via-decoder", decoder);
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+        if (PipelineUtil.containsCause(cause, CancelCodecException.class)) return;
+        super.exceptionCaught(ctx, cause);
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/handler/clientside/ProtocolDetectionHandler.java

@@ -0,0 +1,79 @@
+package com.viaversion.fabric.mc115.handler.clientside;
+
+import com.viaversion.fabric.mc115.ViaFabric;
+import com.viaversion.fabric.mc115.service.ProtocolAutoDetector;
+import com.viaversion.viaversion.util.Pair;
+import io.netty.channel.ChannelDuplexHandler;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelPromise;
+
+import java.net.InetSocketAddress;
+import java.util.ArrayDeque;
+import java.util.Queue;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.TimeUnit;
+
+public class ProtocolDetectionHandler extends ChannelDuplexHandler {
+    private final Queue<Pair<Object, ChannelPromise>> queuedMessages = new ArrayDeque<>();
+    private boolean hold = true;
+    private boolean pendentFlush;
+
+    @Override
+    public void channelActive(ChannelHandlerContext ctx) throws Exception {
+        super.channelActive(ctx);
+        if (ctx.channel().remoteAddress() instanceof InetSocketAddress) {
+            ScheduledFuture<?> timeoutRun = ctx.executor().schedule(() -> {
+                ViaFabric.JLOGGER.warning("Timeout for protocol auto-detection in "
+                        + ctx.channel().remoteAddress() + " server");
+                hold = false;
+                drainQueue(ctx);
+                ctx.pipeline().remove(this);
+            }, 10, TimeUnit.SECONDS);
+            ProtocolAutoDetector.detectVersion(((InetSocketAddress) ctx.channel().remoteAddress()))
+                    .whenComplete((obj, ex) -> {
+                        ctx.pipeline().remove(this);
+                        timeoutRun.cancel(false);
+                    });
+            // Let's cache it before we need it
+        }
+    }
+
+    @Override
+    public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception {
+        if (!hold) {
+            drainQueue(ctx);
+            super.write(ctx, msg, promise);
+        } else {
+            queuedMessages.add(new Pair<>(msg, promise));
+        }
+    }
+
+    @Override
+    public void flush(ChannelHandlerContext ctx) throws Exception {
+        if (!hold) {
+            drainQueue(ctx);
+            super.flush(ctx);
+        } else {
+            pendentFlush = true;
+        }
+    }
+
+    @Override
+    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
+        drainQueue(ctx);
+        super.channelInactive(ctx);
+    }
+
+    private void drainQueue(ChannelHandlerContext ctx) {
+        queuedMessages.forEach(it -> ctx.write(it.getKey(), it.getValue()));
+        queuedMessages.clear();
+        if (pendentFlush) ctx.flush();
+        pendentFlush = false;
+    }
+
+    @Override
+    public void handlerRemoved(ChannelHandlerContext ctx) throws Exception {
+        drainQueue(ctx);
+        super.handlerRemoved(ctx);
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/mixin/address/client/MixinConnectScreenThread.java

@@ -0,0 +1,24 @@
+package com.viaversion.fabric.mc115.mixin.address.client;
+
+import com.viaversion.fabric.mc115.ViaFabricAddress;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Redirect;
+
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
+@Mixin(targets = "net/minecraft/client/gui/screen/ConnectScreen$1", priority = 2000)
+public class MixinConnectScreenThread {
+    @Redirect(method = "run()V", at = @At(value = "INVOKE",
+            target = "Ljava/net/InetAddress;getByName(Ljava/lang/String;)Ljava/net/InetAddress;"))
+    private InetAddress resolveViaFabricAddr(String address) throws UnknownHostException {
+        ViaFabricAddress viaAddr = new ViaFabricAddress().parse(address);
+        if (viaAddr.viaSuffix == null) {
+            return InetAddress.getByName(address);
+        }
+
+        InetAddress resolved = InetAddress.getByName(viaAddr.realAddress);
+        return InetAddress.getByAddress(resolved.getHostName() + "." + viaAddr.viaSuffix, resolved.getAddress());
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/mixin/address/client/MixinServerAddress.java

@@ -0,0 +1,29 @@
+package com.viaversion.fabric.mc115.mixin.address.client;
+
+import com.viaversion.fabric.mc115.ViaFabricAddress;
+import net.minecraft.network.ServerAddress;
+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.Redirect;
+
+@Mixin(ServerAddress.class)
+public abstract class MixinServerAddress {
+    @Shadow
+    private static String[] resolveSrv(String address) {
+        throw new AssertionError();
+    }
+
+    @Redirect(method = "parse", at = @At(value = "INVOKE", target = "Lnet/minecraft/network/ServerAddress;resolveSrv(Ljava/lang/String;)[Ljava/lang/String;"))
+    private static String[] modifySrvAddr(String address) {
+        ViaFabricAddress viaAddr = new ViaFabricAddress().parse(address);
+        if (viaAddr.viaSuffix == null) {
+            return resolveSrv(address);
+        }
+
+        String[] resolvedSrv = resolveSrv(viaAddr.realAddress);
+        resolvedSrv[0] = resolvedSrv[0].replaceAll("\\.$", "") + "." + viaAddr.viaSuffix;
+
+        return resolvedSrv;
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/mixin/address/client/MixinServerPinger.java

@@ -0,0 +1,25 @@
+package com.viaversion.fabric.mc115.mixin.address.client;
+
+import com.viaversion.fabric.mc115.ViaFabricAddress;
+import net.minecraft.client.network.MultiplayerServerListPinger;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Redirect;
+
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
+@Mixin(MultiplayerServerListPinger.class)
+public class MixinServerPinger {
+    @Redirect(method = "add", at = @At(value = "INVOKE",
+            target = "Ljava/net/InetAddress;getByName(Ljava/lang/String;)Ljava/net/InetAddress;"))
+    private InetAddress resolveViaFabricAddr(String address) throws UnknownHostException {
+        ViaFabricAddress viaAddr = new ViaFabricAddress().parse(address);
+        if (viaAddr.viaSuffix == null) {
+            return InetAddress.getByName(address);
+        }
+
+        InetAddress resolved = InetAddress.getByName(viaAddr.realAddress);
+        return InetAddress.getByAddress(resolved.getHostName() + "." + viaAddr.viaSuffix, resolved.getAddress());
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/mixin/debug/client/MixinClientConnectionAccessor.java

@@ -0,0 +1,12 @@
+package com.viaversion.fabric.mc115.mixin.debug.client;
+
+import io.netty.channel.Channel;
+import net.minecraft.network.ClientConnection;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.gen.Accessor;
+
+@Mixin(ClientConnection.class)
+public interface MixinClientConnectionAccessor {
+    @Accessor
+    Channel getChannel();
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/mixin/debug/client/MixinDebugHud.java

@@ -0,0 +1,38 @@
+package com.viaversion.fabric.mc115.mixin.debug.client;
+
+import com.viaversion.fabric.mc115.handler.CommonTransformer;
+import com.viaversion.fabric.mc115.handler.FabricDecodeHandler;
+import com.viaversion.viaversion.api.connection.ProtocolInfo;
+import io.netty.channel.ChannelHandler;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.gui.hud.DebugHud;
+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;
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+
+import java.util.List;
+
+@Mixin(DebugHud.class)
+public class MixinDebugHud {
+    @Inject(at = @At("RETURN"), method = "getLeftText")
+    protected void getLeftText(CallbackInfoReturnable<List<String>> info) {
+        String line = "[ViaFabric] I: " + Via.getManager().getConnectionManager().getConnections().size() + " (F: "
+                + Via.getManager().getConnectionManager().getConnectedClients().size() + ")";
+        @SuppressWarnings("ConstantConditions") ChannelHandler viaDecoder = ((MixinClientConnectionAccessor) MinecraftClient.getInstance().getNetworkHandler()
+                .getConnection()).getChannel().pipeline().get(CommonTransformer.HANDLER_DECODER_NAME);
+        if (viaDecoder instanceof FabricDecodeHandler) {
+            ProtocolInfo protocol = ((FabricDecodeHandler) viaDecoder).getInfo().getProtocolInfo();
+            if (protocol != null) {
+                ProtocolVersion serverVer = ProtocolVersion.getProtocol(protocol.getServerProtocolVersion());
+                ProtocolVersion clientVer = ProtocolVersion.getProtocol(protocol.getProtocolVersion());
+                line += " / C: " + clientVer.getName() + " (" + clientVer.getVersion() + ") S: "
+                        + serverVer.getName() + " (" + serverVer.getVersion() + ") A: " + protocol.getUser().isActive();
+            }
+        }
+
+        info.getReturnValue().add(line);
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/mixin/gui/client/MixinMultiplayerScreen.java

@@ -0,0 +1,38 @@
+package com.viaversion.fabric.mc115.mixin.gui.client;
+
+import com.viaversion.fabric.mc115.ViaFabric;
+import com.viaversion.fabric.mc115.gui.ViaConfigScreen;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.gui.screen.Screen;
+import net.minecraft.client.gui.screen.multiplayer.MultiplayerScreen;
+import net.minecraft.client.gui.widget.ButtonWidget;
+import net.minecraft.client.gui.widget.TexturedButtonWidget;
+import net.minecraft.text.Text;
+import net.minecraft.text.TranslatableText;
+import net.minecraft.util.Identifier;
+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(MultiplayerScreen.class)
+public abstract class MixinMultiplayerScreen extends Screen {
+    protected MixinMultiplayerScreen(Text title, UnsupportedOperationException e) {
+        super(title);
+        throw e;
+    }
+
+    @Inject(method = "init", at = @At("TAIL"), remap = false)
+    private void onInit(CallbackInfo ci) {
+        ButtonWidget enableClientSideViaVersion = new TexturedButtonWidget(this.width / 2 + 113, 10,
+                40, 20, // Size
+                0, 0, // Start pos of texture
+                20, // v Hover offset
+                new Identifier("viafabric:textures/gui/widgets.png"),
+                256, 256, // Texture size
+                it -> MinecraftClient.getInstance().openScreen(new ViaConfigScreen(this)),
+                new TranslatableText("gui.via_button").asString());
+        if (ViaFabric.config.isHideButton()) enableClientSideViaVersion.visible = false;
+        addButton(enableClientSideViaVersion);
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/mixin/pipeline/MixinClientConnection.java

@@ -0,0 +1,31 @@
+package com.viaversion.fabric.mc115.mixin.pipeline;
+
+import io.netty.channel.Channel;
+import net.minecraft.network.ClientConnection;
+import org.apache.logging.log4j.Logger;
+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.Redirect;
+
+
+@Mixin(ClientConnection.class)
+public class MixinClientConnection {
+    @Shadow
+    private Channel channel;
+
+    @Redirect(
+            method = "exceptionCaught",
+            remap = false,
+            at = @At(
+                    value = "INVOKE",
+                    target = "Lorg/apache/logging/log4j/Logger;debug(Ljava/lang/String;Ljava/lang/Throwable;)V"
+            ))
+    private void redirectDebug(Logger logger, String message, Throwable t) {
+        if ("Failed to sent packet".equals(message)) {
+            logger.info(message, t);
+        } else {
+            logger.debug(message, t);
+        }
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/mixin/pipeline/MixinServerNetworkIoChInit.java

@@ -0,0 +1,28 @@
+package com.viaversion.fabric.mc115.mixin.pipeline;
+
+import com.viaversion.fabric.mc115.handler.CommonTransformer;
+import com.viaversion.fabric.mc115.handler.FabricDecodeHandler;
+import com.viaversion.fabric.mc115.handler.FabricEncodeHandler;
+import com.viaversion.viaversion.connection.UserConnectionImpl;
+import com.viaversion.viaversion.protocol.ProtocolPipelineImpl;
+import io.netty.channel.Channel;
+import io.netty.channel.socket.SocketChannel;
+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;
+import com.viaversion.viaversion.api.connection.UserConnection;
+
+@Mixin(targets = "net.minecraft.server.ServerNetworkIo$1")
+public class MixinServerNetworkIoChInit {
+    @Inject(method = "initChannel", at = @At(value = "TAIL"), remap = false)
+    private void onInitChannel(Channel channel, CallbackInfo ci) {
+        if (channel instanceof SocketChannel) {
+            UserConnection user = new UserConnectionImpl(channel);
+            new ProtocolPipelineImpl(user);
+
+            channel.pipeline().addBefore("encoder", CommonTransformer.HANDLER_ENCODER_NAME, new FabricEncodeHandler(user));
+            channel.pipeline().addBefore("decoder", CommonTransformer.HANDLER_DECODER_NAME, new FabricDecodeHandler(user));
+        }
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/mixin/pipeline/client/MixinClientConnectionChInit.java

@@ -0,0 +1,35 @@
+package com.viaversion.fabric.mc115.mixin.pipeline.client;
+
+import com.viaversion.fabric.mc115.ViaFabric;
+import com.viaversion.fabric.mc115.handler.CommonTransformer;
+import com.viaversion.fabric.mc115.handler.FabricDecodeHandler;
+import com.viaversion.fabric.mc115.handler.FabricEncodeHandler;
+import com.viaversion.fabric.mc115.handler.clientside.ProtocolDetectionHandler;
+import com.viaversion.fabric.mc115.protocol.ViaFabricHostnameProtocol;
+import com.viaversion.viaversion.connection.UserConnectionImpl;
+import com.viaversion.viaversion.protocol.ProtocolPipelineImpl;
+import io.netty.channel.Channel;
+import io.netty.channel.socket.SocketChannel;
+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;
+import com.viaversion.viaversion.api.connection.UserConnection;
+
+@Mixin(targets = "net.minecraft.network.ClientConnection$1")
+public class MixinClientConnectionChInit {
+    @Inject(method = "initChannel", at = @At(value = "TAIL"), remap = false)
+    private void onInitChannel(Channel channel, CallbackInfo ci) {
+        if (channel instanceof SocketChannel) {
+            UserConnection user = new UserConnectionImpl(channel, true);
+            new ProtocolPipelineImpl(user).add(ViaFabricHostnameProtocol.INSTANCE);
+
+            channel.pipeline()
+                    .addBefore("encoder", CommonTransformer.HANDLER_ENCODER_NAME, new FabricEncodeHandler(user))
+                    .addBefore("decoder", CommonTransformer.HANDLER_DECODER_NAME, new FabricDecodeHandler(user));
+            if (ViaFabric.config.isClientSideEnabled()) {
+                channel.pipeline().addAfter(CommonTransformer.HANDLER_ENCODER_NAME, "via-autoprotocol", new ProtocolDetectionHandler());
+            }
+        }
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/platform/VRInjector.java

@@ -0,0 +1,61 @@
+package com.viaversion.fabric.mc115.platform;
+
+import com.viaversion.fabric.mc115.handler.CommonTransformer;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.loader.api.FabricLoader;
+import net.minecraft.SharedConstants;
+import com.viaversion.viaversion.api.platform.ViaInjector;
+import com.viaversion.viaversion.util.GsonUtil;
+import com.viaversion.viaversion.libs.gson.JsonObject;
+
+import java.lang.reflect.Method;
+import java.util.Arrays;
+
+public class VRInjector implements ViaInjector {
+    @Override
+    public void inject() {
+        // *looks at Mixins*
+    }
+
+    @Override
+    public void uninject() {
+        // not possible *plays sad violin*
+    }
+
+    @Override
+    public int getServerProtocolVersion() {
+        return SharedConstants.getGameVersion().getProtocolVersion();
+    }
+
+    @Override
+    public String getEncoderName() {
+        return CommonTransformer.HANDLER_ENCODER_NAME;
+    }
+
+    @Override
+    public String getDecoderName() {
+        return CommonTransformer.HANDLER_DECODER_NAME;
+    }
+
+    @Override
+    public JsonObject getDump() {
+        JsonObject obj = new JsonObject();
+        try {
+            obj.add("serverNetworkIOChInit", GsonUtil.getGson().toJsonTree(
+                    Arrays.stream(Class.forName("net.minecraft.class_3242$1").getDeclaredMethods())
+                            .map(Method::toString)
+                            .toArray(String[]::new)));
+        } catch (ClassNotFoundException ignored) {
+        }
+        if (FabricLoader.getInstance().getEnvironmentType() == EnvType.CLIENT) {
+            try {
+                obj.add("clientConnectionChInit", GsonUtil.getGson().toJsonTree(
+                        Arrays.stream(Class.forName("net.minecraft.class_2535$1").getDeclaredMethods())
+                                .map(Method::toString)
+                                .toArray(String[]::new)));
+            } catch (ClassNotFoundException ignored) {
+            }
+        }
+        return obj;
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/platform/VRLoader.java

@@ -0,0 +1,34 @@
+package com.viaversion.fabric.mc115.platform;
+
+import com.viaversion.fabric.mc115.providers.VRHandItemProvider;
+import com.viaversion.fabric.mc115.providers.VRVersionProvider;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.loader.api.FabricLoader;
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.platform.ViaPlatformLoader;
+import com.viaversion.viaversion.bungee.providers.BungeeMovementTransmitter;
+import com.viaversion.viaversion.api.protocol.version.VersionProvider;
+import com.viaversion.viaversion.protocols.protocol1_9to1_8.providers.HandItemProvider;
+import com.viaversion.viaversion.protocols.protocol1_9to1_8.providers.MovementTransmitterProvider;
+
+public class VRLoader implements ViaPlatformLoader {
+    @Override
+    public void load() {
+        Via.getManager().getProviders().use(MovementTransmitterProvider.class, new BungeeMovementTransmitter());
+        Via.getManager().getProviders().use(VersionProvider.class, new VRVersionProvider());
+
+        if (Via.getPlatform().getConf().isItemCache()) {
+            VRHandItemProvider handProvider = new VRHandItemProvider();
+            if (FabricLoader.getInstance().getEnvironmentType() == EnvType.CLIENT) {
+                handProvider.registerClientTick();
+            }
+            handProvider.registerServerTick();
+            Via.getManager().getProviders().use(HandItemProvider.class, handProvider);
+        }
+    }
+
+    @Override
+    public void unload() {
+        // Nothing to do
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/platform/VRPlatform.java

@@ -0,0 +1,272 @@
+package com.viaversion.fabric.mc115.platform;
+
+import com.viaversion.fabric.mc115.ViaFabric;
+import com.viaversion.fabric.mc115.commands.NMSCommandSender;
+import com.viaversion.fabric.mc115.commands.UserCommandSender;
+import com.viaversion.fabric.mc115.util.FutureTaskId;
+import com.viaversion.fabric.mc115.util.JLoggerToLog4j;
+import com.viaversion.viaversion.api.configuration.ViaVersionConfig;
+import com.viaversion.viaversion.api.platform.PlatformTask;
+import io.netty.util.concurrent.Future;
+import io.netty.util.concurrent.GenericFutureListener;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.api.Environment;
+import net.fabricmc.loader.api.FabricLoader;
+import net.fabricmc.loader.api.ModContainer;
+import net.fabricmc.loader.api.Version;
+import net.fabricmc.loader.api.metadata.ModMetadata;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.entity.Entity;
+import net.minecraft.network.MessageType;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.minecraft.text.Text;
+import org.apache.logging.log4j.LogManager;
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.ViaAPI;
+import com.viaversion.viaversion.api.command.ViaCommandSender;
+import com.viaversion.viaversion.api.configuration.ConfigurationProvider;
+import com.viaversion.viaversion.api.platform.ViaPlatform;
+import com.viaversion.viaversion.dump.PluginInfo;
+import com.viaversion.viaversion.util.GsonUtil;
+import com.viaversion.viaversion.libs.gson.JsonObject;
+import com.viaversion.viaversion.libs.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
+import com.viaversion.viaversion.libs.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
+
+import java.io.File;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
+import java.util.concurrent.CancellationException;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.TimeUnit;
+import java.util.function.Supplier;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import java.util.stream.Collectors;
+
+public class VRPlatform implements ViaPlatform<UUID> {
+    private final Logger logger = new JLoggerToLog4j(LogManager.getLogger("ViaVersion"));
+    private final VRViaConfig config;
+    private final File dataFolder;
+    private final ViaAPI<UUID> api;
+
+    public VRPlatform() {
+        Path configDir = FabricLoader.getInstance().getConfigDirectory().toPath().resolve("ViaFabric");
+        config = new VRViaConfig(configDir.resolve("viaversion.yml").toFile());
+        dataFolder = configDir.toFile();
+        api = new VRViaAPI();
+    }
+
+    public static MinecraftServer getServer() {
+        if (FabricLoader.getInstance().getEnvironmentType() == EnvType.CLIENT) {
+            return getIntegratedServer();
+        }
+        return (MinecraftServer) FabricLoader.getInstance().getGameInstance();
+    }
+
+    @Environment(EnvType.CLIENT)
+    private static MinecraftServer getIntegratedServer() {
+        return MinecraftClient.getInstance().getServer();
+    }
+
+    public static String legacyToJson(String legacy) {
+        return GsonComponentSerializer.gson().serialize(LegacyComponentSerializer.legacySection().deserialize(legacy));
+    }
+
+    @Override
+    public Logger getLogger() {
+        return logger;
+    }
+
+    @Override
+    public String getPlatformName() {
+        return "ViaFabric";
+    }
+
+    @Override
+    public String getPlatformVersion() {
+        return ViaFabric.getVersion();
+    }
+
+    @Override
+    public String getPluginVersion() {
+        return FabricLoader.getInstance().getModContainer("viaversion").map(ModContainer::getMetadata)
+                .map(ModMetadata::getVersion).map(Version::getFriendlyString).orElse("UNKNOWN");
+    }
+
+    @Override
+    public FutureTaskId runAsync(Runnable runnable) {
+        return new FutureTaskId(CompletableFuture
+                .runAsync(runnable, ViaFabric.ASYNC_EXECUTOR)
+                .exceptionally(throwable -> {
+                    if (!(throwable instanceof CancellationException)) {
+                        throwable.printStackTrace();
+                    }
+                    return null;
+                })
+        );
+    }
+
+    @Override
+    public FutureTaskId runSync(Runnable runnable) {
+        if (getServer() != null) {
+            return runServerSync(runnable);
+        } else {
+            return runEventLoop(runnable);
+        }
+    }
+
+    private FutureTaskId runServerSync(Runnable runnable) {
+        // Kick task needs to be on main thread, it does already have error logger
+        return new FutureTaskId(CompletableFuture.runAsync(runnable, getServer()));
+    }
+
+    private FutureTaskId runEventLoop(Runnable runnable) {
+        return new FutureTaskId(
+                ViaFabric.EVENT_LOOP
+                        .submit(runnable)
+                        .addListener(errorLogger())
+        );
+    }
+
+    @Override
+    public PlatformTask runSync(Runnable runnable, Long ticks) {
+        // ViaVersion seems to not need to run delayed tasks on main thread
+        return new FutureTaskId(
+                ViaFabric.EVENT_LOOP
+                        .schedule(() -> runSync(runnable), ticks * 50, TimeUnit.MILLISECONDS)
+                        .addListener(errorLogger())
+        );
+    }
+
+    @Override
+    public PlatformTask runRepeatingSync(Runnable runnable, Long ticks) {
+        // ViaVersion seems to not need to run repeating tasks on main thread
+        return new FutureTaskId(
+                ViaFabric.EVENT_LOOP
+                        .scheduleAtFixedRate(() -> runSync(runnable), 0, ticks * 50, TimeUnit.MILLISECONDS)
+                        .addListener(errorLogger())
+        );
+    }
+
+    private <T extends Future<?>> GenericFutureListener<T> errorLogger() {
+        return future -> {
+            if (!future.isCancelled() && future.cause() != null) {
+                future.cause().printStackTrace();
+            }
+        };
+    }
+
+    @Override
+    public ViaCommandSender[] getOnlinePlayers() {
+        MinecraftServer server = getServer();
+        if (server != null && server.isOnThread()) {
+            return getServerPlayers();
+        }
+        return Via.getManager().getConnectionManager().getConnectedClients().values().stream()
+                .map(UserCommandSender::new)
+                .toArray(ViaCommandSender[]::new);
+    }
+
+    private ViaCommandSender[] getServerPlayers() {
+        return getServer().getPlayerManager().getPlayerList().stream()
+                .map(Entity::getCommandSource)
+                .map(NMSCommandSender::new)
+                .toArray(ViaCommandSender[]::new);
+    }
+
+    @Override
+    public void sendMessage(UUID uuid, String s) {
+        sendMessageServer(uuid, s);
+    }
+
+    private void sendMessageServer(UUID uuid, String s) {
+        MinecraftServer server = getServer();
+        if (server == null) return;
+        runServerSync(() -> {
+            ServerPlayerEntity player = server.getPlayerManager().getPlayer(uuid);
+            if (player == null) return;
+            player.sendChatMessage(Text.Serializer.fromJson(legacyToJson(s)), MessageType.SYSTEM);
+        });
+    }
+
+    @Override
+    public boolean kickPlayer(UUID uuid, String s) {
+        return kickServer(uuid, s);
+    }
+
+    private boolean kickServer(UUID uuid, String s) {
+        MinecraftServer server = getServer();
+        if (server == null) return false;
+        Supplier<Boolean> kickTask = () -> {
+            ServerPlayerEntity player = server.getPlayerManager().getPlayer(uuid);
+            if (player == null) return false;
+            player.networkHandler.disconnect(Text.Serializer.fromJson(legacyToJson(s)));
+            return true;
+        };
+        if (server.isOnThread()) {
+            return kickTask.get();
+        } else {
+            ViaFabric.JLOGGER.log(Level.WARNING, "Weird!? Player kicking was called off-thread", new Throwable());
+            runServerSync(kickTask::get);
+        }
+        return false;  // Can't know if it worked
+    }
+
+    @Override
+    public boolean isPluginEnabled() {
+        return true;
+    }
+
+    @Override
+    public ViaAPI<UUID> getApi() {
+        return api;
+    }
+
+    @Override
+    public ViaVersionConfig getConf() {
+        return config;
+    }
+
+    @Override
+    public ConfigurationProvider getConfigurationProvider() {
+        return config;
+    }
+
+    @Override
+    public File getDataFolder() {
+        return dataFolder;
+    }
+
+    @Override
+    public void onReload() {
+        // Nothing to do
+    }
+
+    @Override
+    public JsonObject getDump() {
+        JsonObject platformSpecific = new JsonObject();
+        List<PluginInfo> mods = new ArrayList<>();
+        for (ModContainer mod : FabricLoader.getInstance().getAllMods()) {
+            mods.add(new PluginInfo(true,
+                    mod.getMetadata().getId() + " (" + mod.getMetadata().getName() + ")",
+                    mod.getMetadata().getVersion().getFriendlyString(),
+                    null,
+                    mod.getMetadata().getAuthors().stream()
+                            .map(info -> info.getName()
+                                    + (info.getContact().asMap().isEmpty() ? "" : " " + info.getContact().asMap()))
+                            .collect(Collectors.toList())
+            ));
+        }
+
+        platformSpecific.add("mods", GsonUtil.getGson().toJsonTree(mods));
+        return platformSpecific;
+    }
+
+    @Override
+    public boolean isOldClientsAllowed() {
+        return true;
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/platform/VRViaAPI.java

@@ -0,0 +1,8 @@
+package com.viaversion.fabric.mc115.platform;
+
+import com.viaversion.viaversion.ViaAPIBase;
+
+import java.util.UUID;
+
+public class VRViaAPI extends ViaAPIBase<UUID> {
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/platform/VRViaConfig.java

@@ -0,0 +1,68 @@
+package com.viaversion.fabric.mc115.platform;
+
+import com.viaversion.viaversion.configuration.AbstractViaConfig;
+
+import java.io.File;
+import java.net.URL;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+
+public class VRViaConfig extends AbstractViaConfig {
+    // Based on Sponge ViaVersion
+    private static List<String> UNSUPPORTED = Arrays.asList("anti-xray-patch", "bungee-ping-interval",
+            "bungee-ping-save", "bungee-servers", "quick-move-action-fix", "nms-player-ticking",
+            "velocity-ping-interval", "velocity-ping-save", "velocity-servers",
+            "blockconnection-method", "change-1_9-hitbox", "change-1_14-hitbox");
+
+    public VRViaConfig(File configFile) {
+        super(configFile);
+        // Load config
+        reloadConfig();
+    }
+
+    @Override
+    public URL getDefaultConfigURL() {
+        return getClass().getClassLoader().getResource("assets/viaversion/config.yml");
+    }
+
+    @Override
+    protected void handleConfig(Map<String, Object> config) {
+        // Nothing Currently
+    }
+
+    @Override
+    public List<String> getUnsupportedOptions() {
+        return UNSUPPORTED;
+    }
+
+    @Override
+    public boolean isAntiXRay() {
+        return false;
+    }
+
+    @Override
+    public boolean isNMSPlayerTicking() {
+        return false;
+    }
+
+    @Override
+    public boolean is1_12QuickMoveActionFix() {
+        return false;
+    }
+
+    @Override
+    public String getBlockConnectionMethod() {
+        return "packet";
+    }
+
+    @Override
+    public boolean is1_9HitboxFix() {
+        return false;
+    }
+
+    @Override
+    public boolean is1_14HitboxFix() {
+        return false;
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/protocol/ViaFabricHostnameProtocol.java

@@ -0,0 +1,34 @@
+package com.viaversion.fabric.mc115.protocol;
+
+import com.viaversion.fabric.mc115.ViaFabricAddress;
+import com.viaversion.viaversion.api.protocol.AbstractSimpleProtocol;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.protocol.remapper.PacketRemapper;
+import com.viaversion.viaversion.api.protocol.remapper.ValueTransformer;
+import com.viaversion.viaversion.api.type.Type;
+import com.viaversion.viaversion.api.protocol.packet.State;
+
+public class ViaFabricHostnameProtocol extends AbstractSimpleProtocol {
+    public static final ViaFabricHostnameProtocol INSTANCE = new ViaFabricHostnameProtocol();
+
+    @Override
+    protected void registerPackets() {
+        registerServerbound(State.HANDSHAKE, 0, 0, new PacketRemapper() {
+            @Override
+            public void registerMap() {
+                map(Type.VAR_INT); // Protocol version
+                map(Type.STRING, new ValueTransformer<String, String>(Type.STRING) {
+                    @Override
+                    public String transform(PacketWrapper packetWrapper, String s) {
+                        return new ViaFabricAddress().parse(s).realAddress;
+                    }
+                });
+            }
+        });
+    }
+
+    @Override
+    public boolean isBaseProtocol() {
+        return true;
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/providers/VRHandItemProvider.java

@@ -0,0 +1,110 @@
+package com.viaversion.fabric.mc115.providers;
+
+import com.viaversion.fabric.mc115.ViaFabric;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.api.Environment;
+import net.fabricmc.fabric.api.client.event.lifecycle.v1.ClientTickEvents;
+import net.fabricmc.fabric.api.event.lifecycle.v1.ServerTickEvents;
+import net.fabricmc.fabric.api.event.world.WorldTickCallback;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.network.ClientPlayerEntity;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.registry.Registry;
+import net.minecraft.util.Identifier;
+import net.minecraft.world.World;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.minecraft.item.Item;
+import com.viaversion.viaversion.protocols.protocol1_9to1_8.providers.HandItemProvider;
+
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+
+public class VRHandItemProvider extends HandItemProvider {
+    public Item clientItem = null;
+    public Map<UUID, Item> serverPlayers = new ConcurrentHashMap<>();
+
+    @Override
+    public Item getHandItem(UserConnection info) {
+        Item serverItem;
+        if (info.isClientSide()) {
+            return getClientItem();
+        } else if ((serverItem = serverPlayers.get(info.getProtocolInfo().getUuid())) != null) {
+            return new Item(serverItem);
+        }
+        return super.getHandItem(info);
+    }
+
+    private Item getClientItem() {
+        if (clientItem == null) {
+            return new Item(0, (byte) 0, (short) 0, null);
+        }
+        return new Item(clientItem);
+    }
+
+    @Environment(EnvType.CLIENT)
+    public void registerClientTick() {
+        try {
+            ClientTickEvents.END_WORLD_TICK.register(clientWorld -> tickClient());
+        } catch (NoClassDefFoundError ignored) {
+            try {
+                WorldTickCallback.EVENT.register(world -> {
+                    if (world.isClient) {
+                        tickClient();
+                    }
+                });
+            } catch (NoClassDefFoundError ignored2) {
+                ViaFabric.JLOGGER.info("Fabric Lifecycle V0/V1 isn't installed");
+            }
+        }
+    }
+
+    public void registerServerTick() {
+        try {
+            ServerTickEvents.END_WORLD_TICK.register(this::tickServer);
+        } catch (NoClassDefFoundError ignored) {
+            WorldTickCallback.EVENT.register(world -> {
+                if (!world.isClient) {
+                    tickServer(world);
+                }
+            });
+        }
+    }
+
+    private void tickClient() {
+        ClientPlayerEntity p = MinecraftClient.getInstance().player;
+        if (p != null) {
+            clientItem = fromNative(p.inventory.getMainHandStack());
+        }
+    }
+
+    private void tickServer(World world) {
+        serverPlayers.clear();
+        world.getPlayers().forEach(it -> serverPlayers
+                .put(it.getUuid(), fromNative(it.inventory.getMainHandStack())));
+    }
+
+    private Item fromNative(ItemStack original) {
+        Identifier iid = Registry.ITEM.getId(original.getItem());
+        if (iid == null) return new Item(0, (byte) 0, (short) 0, null);
+        int id = swordId(iid.toString());
+        return new Item(id, (byte) original.getCount(), (short) original.getDamage(), null);
+    }
+
+    private int swordId(String id) {
+        // https://github.com/ViaVersion/ViaVersion/blob/8de26a0ad33f5b739f5394ed80f69d14197fddc7/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_9to1_8/Protocol1_9To1_8.java#L86
+        switch (id) {
+            case "minecraft:iron_sword":
+                return 267;
+            case "minecraft:wooden_sword":
+                return 268;
+            case "minecraft:golden_sword":
+                return 272;
+            case "minecraft:diamond_sword":
+                return 276;
+            case "minecraft:stone_sword":
+                return 283;
+        }
+        return 0;
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/providers/VRVersionProvider.java

@@ -0,0 +1,166 @@
+package com.viaversion.fabric.mc115.providers;
+
+import com.viaversion.fabric.mc115.ViaFabric;
+import com.viaversion.fabric.mc115.ViaFabricAddress;
+import com.viaversion.fabric.mc115.service.ProtocolAutoDetector;
+import com.viaversion.fabric.mc115.util.ProtocolUtils;
+import com.google.common.primitives.Ints;
+import com.viaversion.viaversion.api.connection.ProtocolInfo;
+import net.fabricmc.loader.api.FabricLoader;
+import net.minecraft.network.ClientConnection;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+import com.viaversion.viaversion.api.type.Type;
+import com.viaversion.viaversion.exception.CancelException;
+import com.viaversion.viaversion.api.protocol.packet.State;
+import com.viaversion.viaversion.protocols.base.*;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.net.InetSocketAddress;
+import java.net.SocketAddress;
+import java.util.*;
+import java.util.stream.IntStream;
+
+public class VRVersionProvider extends BaseVersionProvider {
+    private int[] multiconnectSupportedVersions = null;
+
+    {
+        try {
+            if (FabricLoader.getInstance().isModLoaded("multiconnect")) {
+                Class<?> mcApiClass = Class.forName("net.earthcomputer.multiconnect.api.MultiConnectAPI");
+                Class<?> iProtocolClass = Class.forName("net.earthcomputer.multiconnect.api.IProtocol");
+                Object mcApiInstance = mcApiClass.getMethod("instance").invoke(null);
+                List<?> protocols = (List<?>) mcApiClass.getMethod("getSupportedProtocols").invoke(mcApiInstance);
+                Method getValue = iProtocolClass.getMethod("getValue");
+                Method isMulticonnectBeta;
+                try {
+                    isMulticonnectBeta = iProtocolClass.getMethod("isMulticonnectBeta");
+                } catch (NoSuchMethodException e) {
+                    isMulticonnectBeta = null;
+                }
+                Set<Integer> vers = new TreeSet<>();
+                for (Object protocol : protocols) {
+                    // Do not use versions with beta multiconnect support, which may have stability issues
+                    if (isMulticonnectBeta == null || !(Boolean) isMulticonnectBeta.invoke(protocol)) {
+                        vers.add((Integer) getValue.invoke(protocol));
+                    }
+                }
+                multiconnectSupportedVersions = vers.stream().mapToInt(Integer::intValue).toArray();
+                ViaFabric.JLOGGER.info("ViaFabric will integrate with multiconnect");
+            }
+        } catch (ClassNotFoundException | IllegalAccessException | InvocationTargetException | NoSuchMethodException
+                | ClassCastException ignored) {
+        }
+    }
+
+    @Override
+    public int getClosestServerProtocol(UserConnection connection) throws Exception {
+        if (connection.isClientSide()) {
+            ProtocolInfo info = Objects.requireNonNull(connection.getProtocolInfo());
+
+            if (!ViaFabric.config.isClientSideEnabled()) {
+                return info.getProtocolVersion();
+            }
+
+            int serverVer = ViaFabric.config.getClientSideVersion();
+            SocketAddress addr = connection.getChannel().remoteAddress();
+
+            if (addr instanceof InetSocketAddress) {
+                int addrVersion = new ViaFabricAddress().parse(((InetSocketAddress) addr).getHostName()).protocol;
+                if (addrVersion != 0) serverVer = addrVersion;
+
+                try {
+                    if (serverVer == -2) {
+                        // Hope protocol was autodetected
+                        ProtocolVersion autoVer =
+                                ProtocolAutoDetector.detectVersion((InetSocketAddress) addr).getNow(null);
+                        if (autoVer != null) {
+                            serverVer = autoVer.getVersion();
+                        }
+                    }
+                } catch (Exception e) {
+                    ViaFabric.JLOGGER.warning("Couldn't auto detect: " + e);
+                }
+            }
+
+            boolean blocked = checkAddressBlocked(addr);
+            boolean supported = ProtocolUtils.isSupported(serverVer, info.getProtocolVersion());
+
+            handleMulticonnectPing(connection, info, blocked, serverVer);
+
+            if (blocked || !supported) serverVer = info.getProtocolVersion();
+
+            return serverVer;
+        }
+        return super.getClosestServerProtocol(connection);
+    }
+
+    private boolean checkAddressBlocked(SocketAddress addr) {
+        return addr instanceof InetSocketAddress && (isDisabled(((InetSocketAddress) addr).getHostString())
+                || ((((InetSocketAddress) addr).getAddress() != null) &&
+                (isDisabled(((InetSocketAddress) addr).getAddress().getHostAddress())
+                        || isDisabled(((InetSocketAddress) addr).getAddress().getHostName()))));
+    }
+
+    private void handleMulticonnectPing(UserConnection connection, ProtocolInfo info, boolean blocked, int serverVer) throws Exception {
+        if (info.getState() == State.STATUS
+                && info.getProtocolVersion() == -1
+                && connection.getChannel().pipeline().get(ClientConnection.class).getPacketListener()
+                .getClass().getName().startsWith("net.earthcomputer.multiconnect")
+                && (blocked || ProtocolUtils.isSupported(serverVer, getVersionForMulticonnect(serverVer)))) { // Intercept the connection
+            int multiconnectSuggestion = blocked ? -1 : getVersionForMulticonnect(serverVer);
+            ViaFabric.JLOGGER.info("Sending " + ProtocolVersion.getProtocol(multiconnectSuggestion) + " for multiconnect version detector");
+            PacketWrapper newAnswer = PacketWrapper.create(0x00, null, connection);
+            newAnswer.write(Type.STRING, "{\"version\":{\"name\":\"viafabric integration\",\"protocol\":" + multiconnectSuggestion + "}}");
+            newAnswer.send(info.getPipeline().contains(BaseProtocol1_16.class) ? BaseProtocol1_16.class : BaseProtocol1_7.class, true, true);
+            throw CancelException.generate();
+        }
+    }
+
+    private int getVersionForMulticonnect(int clientSideVersion) {
+        // https://github.com/ViaVersion/ViaVersion/blob/master/velocity/src/main/java/us/myles/ViaVersion/velocity/providers/VelocityVersionProvider.java
+        int[] compatibleProtocols = multiconnectSupportedVersions;
+
+        if (Arrays.binarySearch(compatibleProtocols, clientSideVersion) >= 0) {
+            return clientSideVersion;
+        }
+
+        if (clientSideVersion < compatibleProtocols[0]) {
+            return compatibleProtocols[0];
+        }
+
+        // TODO: This needs a better fix, i.e checking ProtocolRegistry to see if it would work.
+        for (int i = compatibleProtocols.length - 1; i >= 0; i--) {
+            int protocol = compatibleProtocols[i];
+            if (clientSideVersion > protocol && ProtocolVersion.isRegistered(protocol)) {
+                return protocol;
+            }
+        }
+
+        ViaFabric.JLOGGER.severe("multiconnect integration: Panic, no protocol id found for " + clientSideVersion);
+        return clientSideVersion;
+    }
+
+    private boolean isDisabled(String addr) {
+        String[] parts = addr.split("\\.");
+        boolean isNumericIp = parts.length == 4 && Arrays.stream(parts).map(Ints::tryParse).allMatch(Objects::nonNull);
+        return IntStream.range(0, parts.length).anyMatch(i -> {
+            String query;
+            if (isNumericIp) {
+                query = String.join(".", Arrays.stream(parts, 0, i + 1)
+                        .toArray(String[]::new)) + ((i != 3) ? ".*" : "");
+            } else {
+                query = ((i != 0) ? "*." : "") + String.join(".", Arrays.stream(parts, i, parts.length)
+                        .toArray(String[]::new));
+            }
+            if (ViaFabric.config.isForcedDisable(query)) {
+                ViaFabric.JLOGGER.info(addr + " is force-disabled. (Matches " + query + ")");
+                return true;
+            } else {
+                return false;
+            }
+        });
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/service/ProtocolAutoDetector.java

@@ -0,0 +1,125 @@
+package com.viaversion.fabric.mc115.service;
+
+import com.viaversion.fabric.mc115.ViaFabric;
+import com.viaversion.fabric.mc115.ViaFabricAddress;
+import com.google.common.cache.CacheBuilder;
+import com.google.common.cache.CacheLoader;
+import com.google.common.cache.LoadingCache;
+import io.netty.bootstrap.Bootstrap;
+import io.netty.channel.*;
+import io.netty.channel.socket.nio.NioSocketChannel;
+import io.netty.handler.timeout.ReadTimeoutHandler;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.api.Environment;
+import net.minecraft.network.*;
+import net.minecraft.network.listener.ClientQueryPacketListener;
+import net.minecraft.network.packet.c2s.handshake.HandshakeC2SPacket;
+import net.minecraft.network.packet.c2s.query.QueryRequestC2SPacket;
+import net.minecraft.network.packet.s2c.query.QueryPongS2CPacket;
+import net.minecraft.network.packet.s2c.query.QueryResponseS2CPacket;
+import net.minecraft.server.ServerMetadata;
+import net.minecraft.text.LiteralText;
+import net.minecraft.text.Text;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.UnknownHostException;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+import java.util.logging.Level;
+
+@Environment(EnvType.CLIENT)
+public class ProtocolAutoDetector {
+    private static LoadingCache<InetSocketAddress, CompletableFuture<ProtocolVersion>> SERVER_VER = CacheBuilder.newBuilder()
+            .expireAfterAccess(100, TimeUnit.SECONDS)
+            .build(CacheLoader.from((address) -> {
+                CompletableFuture<ProtocolVersion> future = new CompletableFuture<>();
+
+                try {
+                    final ClientConnection clientConnection = new ClientConnection(NetworkSide.CLIENTBOUND);
+
+                    ChannelFuture ch = new Bootstrap()
+                            .group(ClientConnection.CLIENT_IO_GROUP.get())
+                            .channel(NioSocketChannel.class)
+                            .handler(new ChannelInitializer<Channel>() {
+                                protected void initChannel(Channel channel) {
+                                    try {
+                                        channel.config().setOption(ChannelOption.TCP_NODELAY, true);
+                                        channel.config().setOption(ChannelOption.IP_TOS, 0x18); // Stolen from Velocity, low delay, high reliability
+                                    } catch (ChannelException ignored) {
+                                    }
+
+                                    channel.pipeline()
+                                            .addLast("timeout", new ReadTimeoutHandler(30))
+                                            .addLast("splitter", new SplitterHandler())
+                                            .addLast("decoder", new DecoderHandler(NetworkSide.CLIENTBOUND))
+                                            .addLast("prepender", new SizePrepender())
+                                            .addLast("encoder", new PacketEncoder(NetworkSide.SERVERBOUND))
+                                            .addLast("packet_handler", clientConnection);
+                                }
+                            })
+                            .connect(address);
+
+                    ch.addListener(future1 -> {
+                        if (!future1.isSuccess()) {
+                            future.completeExceptionally(future1.cause());
+                        } else {
+                            ch.channel().eventLoop().execute(() -> { // needs to execute after channel init
+                                clientConnection.setPacketListener(new ClientQueryPacketListener() {
+                                    @Override
+                                    public void onResponse(QueryResponseS2CPacket packet) {
+                                        ServerMetadata meta = packet.getServerMetadata();
+                                        ServerMetadata.Version version;
+                                        if (meta != null && (version = meta.getVersion()) != null) {
+                                            ProtocolVersion ver = ProtocolVersion.getProtocol(version.getProtocolVersion());
+                                            future.complete(ver);
+                                            ViaFabric.JLOGGER.info("Auto-detected " + ver + " for " + address);
+                                        } else {
+                                            future.completeExceptionally(new IllegalArgumentException("Null version in query response"));
+                                        }
+                                        clientConnection.disconnect(new LiteralText(""));
+                                    }
+
+                                    @Override
+                                    public void onPong(QueryPongS2CPacket packet) {
+                                        clientConnection.disconnect(new LiteralText("Pong not requested!"));
+                                    }
+
+                                    @Override
+                                    public void onDisconnected(Text reason) {
+                                        future.completeExceptionally(new IllegalStateException(reason.asString()));
+                                    }
+
+                                    @Override
+                                    public ClientConnection getConnection() {
+                                        return clientConnection;
+                                    }
+                                });
+
+                                clientConnection.send(new HandshakeC2SPacket(address.getHostString(),
+                                        address.getPort(), NetworkState.STATUS));
+                                clientConnection.send(new QueryRequestC2SPacket());
+                            });
+                        }
+                    });
+                } catch (Throwable throwable) {
+                    future.completeExceptionally(throwable);
+                }
+
+                return future;
+            }));
+
+    public static CompletableFuture<ProtocolVersion> detectVersion(InetSocketAddress address) {
+        try {
+            InetSocketAddress real = new InetSocketAddress(InetAddress.getByAddress
+                    (new ViaFabricAddress().parse(address.getHostString()).realAddress,
+                            address.getAddress().getAddress()), address.getPort());
+            return SERVER_VER.get(real);
+        } catch (UnknownHostException | ExecutionException e) {
+            ViaFabric.JLOGGER.log(Level.WARNING, "Protocol auto detector error: ", e);
+            return CompletableFuture.completedFuture(null);
+        }
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/util/FutureTaskId.java

@@ -0,0 +1,23 @@
+package com.viaversion.fabric.mc115.util;
+
+import com.viaversion.viaversion.api.platform.PlatformTask;
+
+import java.util.concurrent.Future;
+
+public class FutureTaskId implements PlatformTask<Future<?>> {
+    private final Future<?> object;
+
+    public FutureTaskId(Future<?> object) {
+        this.object = object;
+    }
+
+    @Override
+    public Future<?> getObject() {
+        return object;
+    }
+
+    @Override
+    public void cancel() {
+        object.cancel(false);
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/util/JLoggerToLog4j.java

@@ -0,0 +1,68 @@
+package com.viaversion.fabric.mc115.util;
+
+import java.text.MessageFormat;
+import java.util.logging.Level;
+import java.util.logging.LogRecord;
+import java.util.logging.Logger;
+
+public class JLoggerToLog4j extends Logger {
+    private final org.apache.logging.log4j.Logger base;
+
+    public JLoggerToLog4j(org.apache.logging.log4j.Logger logger) {
+        super("logger", null);
+        this.base = logger;
+    }
+
+    public void log(LogRecord record) {
+        this.log(record.getLevel(), record.getMessage());
+    }
+
+    public void log(Level level, String msg) {
+        if (level == Level.FINE) {
+            this.base.debug(msg);
+        } else if (level == Level.WARNING) {
+            this.base.warn(msg);
+        } else if (level == Level.SEVERE) {
+            this.base.error(msg);
+        } else if (level == Level.INFO) {
+            this.base.info(msg);
+        } else {
+            this.base.trace(msg);
+        }
+
+    }
+
+    public void log(Level level, String msg, Object param1) {
+        if (level == Level.FINE) {
+            this.base.debug(msg, param1);
+        } else if (level == Level.WARNING) {
+            this.base.warn(msg, param1);
+        } else if (level == Level.SEVERE) {
+            this.base.error(msg, param1);
+        } else if (level == Level.INFO) {
+            this.base.info(msg, param1);
+        } else {
+            this.base.trace(msg, param1);
+        }
+
+    }
+
+    public void log(Level level, String msg, Object[] params) {
+        log(level, MessageFormat.format(msg, params));
+    }
+
+    public void log(Level level, String msg, Throwable params) {
+        if (level == Level.FINE) {
+            this.base.debug(msg, params);
+        } else if (level == Level.WARNING) {
+            this.base.warn(msg, params);
+        } else if (level == Level.SEVERE) {
+            this.base.error(msg, params);
+        } else if (level == Level.INFO) {
+            this.base.info(msg, params);
+        } else {
+            this.base.trace(msg, params);
+        }
+
+    }
+}

viafabric-mc115/src/main/java/com/viaversion/fabric/mc115/util/ProtocolUtils.java

@@ -0,0 +1,60 @@
+package com.viaversion.fabric.mc115.util;
+
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+
+import java.util.Arrays;
+import java.util.stream.Stream;
+
+public class ProtocolUtils {
+    public static boolean isSupported(int server, int client) {
+        return server == client || Via.getManager().getProtocolManager().getProtocolPath(client, server) != null;
+    }
+
+    public static String getProtocolName(int id) {
+        if (!ProtocolVersion.isRegistered(id)) return Integer.toString(id);
+        return ProtocolVersion.getProtocol(id).getName();
+    }
+
+    public static boolean isStartOfProtocolText(String s) {
+        try {
+            Integer.parseInt(s);
+            return true;
+        } catch (NumberFormatException e) {
+            try {
+                Integer.parseInt(s + '0');
+                return true;
+            } catch (NumberFormatException e2) {
+                return ProtocolVersion.getProtocols().stream()
+                        .map(ProtocolVersion::getName)
+                        .flatMap(str -> Stream.concat(
+                                Arrays.stream(str.split("-")),
+                                Arrays.stream(new String[]{str})
+                        ))
+                        .anyMatch(ver -> ver.startsWith(s));
+            }
+        }
+    }
+
+    public static Integer parseProtocolId(String s) {
+        try {
+            return Integer.parseInt(s);
+        } catch (NumberFormatException ignored) {
+            ProtocolVersion closest = ProtocolVersion.getClosest(s);
+            if (closest == null) return null;
+            return closest.getVersion();
+        }
+    }
+
+    public static String[] getProtocolSuggestions(String text) {
+        return ProtocolVersion.getProtocols().stream()
+                .map(ProtocolVersion::getName)
+                .flatMap(str -> Stream.concat(
+                        Arrays.stream(str.split("-")),
+                        Arrays.stream(new String[]{str})
+                ))
+                .distinct()
+                .filter(ver -> ver.startsWith(text))
+                .toArray(String[]::new);
+    }
+}

viafabric-mc115/src/main/resources/fabric.mod.json

@@ -0,0 +1,61 @@
+{
+  "schemaVersion": 1,
+  "id": "viafabric-mc115",
+  "name": "ViaFabric",
+  "version": "@version@",
+  "description": "@description@",
+  "license": "GPL-3.0",
+  "contact": {
+    "homepage": "https://viaversion.com/fabric",
+    "issues": "https://github.com/ViaVersion/ViaFabric/issues",
+    "sources": "https://github.com/ViaVersion/ViaFabric"
+  },
+  "environment": "*",
+  "authors": [
+    {
+      "name": "creeper123123321",
+      "contact": {
+        "homepage": "https://creeper123123321.github.io/"
+      }
+    }
+  ],
+  "contributors": [
+    {
+      "name": "GitHub contributors",
+      "contact": {
+        "homepage": "https://github.com/ViaVersion/ViaFabric/graphs/contributors"
+      }
+    }
+  ],
+  "entrypoints": {
+    "main": [
+      "com.viaversion.fabric.mc115.ViaFabric"
+    ],
+    "cotton-client-commands": [
+      "com.viaversion.fabric.mc115.commands.VRClientCommands"
+    ],
+    "modmenu": [
+      "com.viaversion.fabric.mc115.gui.ModMenuConfig"
+    ]
+  },
+  "depends": {
+    "cotton-client-commands": "*",
+    "fabricloader": ">=0.4.0",
+    "fabric-resource-loader-v0": "*",
+    "minecraft": "1.15.x",
+    "viaversion": ">3.0.1"
+  },
+  "conflicts": {
+    "fabric-registry-sync-v0": "*"
+  },
+  "recommends": {
+    "fabric-command-api-v1": "*"
+  },
+  "icon": "assets/viafabric/textures/logo.png",
+  "mixins": [
+    "mixins.viafabric.address.json",
+    "mixins.viafabric.gui.json",
+    "mixins.viafabric.debug.json",
+    "mixins.viafabric.pipeline.json"
+  ]
+}

viafabric-mc115/src/main/resources/mixins.viafabric.address.json

@@ -0,0 +1,14 @@
+{
+  "required": true,
+  "compatibilityLevel": "JAVA_8",
+  "mixins": [
+  ],
+  "client": [
+    "com.viaversion.fabric.mc115.mixin.address.client.MixinConnectScreenThread",
+    "com.viaversion.fabric.mc115.mixin.address.client.MixinServerAddress",
+    "com.viaversion.fabric.mc115.mixin.address.client.MixinServerPinger"
+  ],
+  "injectors": {
+    "defaultRequire": 1
+  }
+}

viafabric-mc115/src/main/resources/mixins.viafabric.debug.json

@@ -0,0 +1,13 @@
+{
+  "required": true,
+  "compatibilityLevel": "JAVA_8",
+  "mixins": [
+  ],
+  "client": [
+    "com.viaversion.fabric.mc115.mixin.debug.client.MixinClientConnectionAccessor",
+    "com.viaversion.fabric.mc115.mixin.debug.client.MixinDebugHud"
+  ],
+  "injectors": {
+    "defaultRequire": 0
+  }
+}

viafabric-mc115/src/main/resources/mixins.viafabric.gui.json

@@ -0,0 +1,12 @@
+{
+  "required": true,
+  "compatibilityLevel": "JAVA_8",
+  "mixins": [
+  ],
+  "client": [
+    "com.viaversion.fabric.mc115.mixin.gui.client.MixinMultiplayerScreen"
+  ],
+  "injectors": {
+    "defaultRequire": 0
+  }
+}

viafabric-mc115/src/main/resources/mixins.viafabric.pipeline.json

@@ -0,0 +1,14 @@
+{
+  "required": true,
+  "compatibilityLevel": "JAVA_8",
+  "mixins": [
+    "com.viaversion.fabric.mc115.mixin.pipeline.MixinClientConnection",
+    "com.viaversion.fabric.mc115.mixin.pipeline.MixinServerNetworkIoChInit"
+  ],
+  "client": [
+    "com.viaversion.fabric.mc115.mixin.pipeline.client.MixinClientConnectionChInit"
+  ],
+  "injectors": {
+    "defaultRequire": 1
+  }
+}

viafabric-mc116/build.gradle.kts

@@ -1,11 +1,10 @@
 version = rootProject.version
 
 dependencies {
-    minecraft("com.mojang:minecraft:1.14.4")
+    minecraft("com.mojang:minecraft:1.16.5")
-    mappings("net.fabricmc:yarn:1.14.4+build.16:v2")
+    mappings("net.fabricmc:yarn:1.16.5+build.6:v2")
-    modImplementation("net.fabricmc:fabric-loader:0.8.2+build.194")
+    modImplementation("net.fabricmc:fabric-loader:0.11.3")
 
-    modImplementation("net.fabricmc.fabric-api:fabric-api:0.13.1+build.257-1.14")
+    modImplementation("net.fabricmc.fabric-api:fabric-api:0.32.5+1.16")
-    modImplementation("io.github.prospector:modmenu:1.7.16.1.14.4+build.128")
+    modImplementation("com.terraformersmc:modmenu:1.16.9")
-    modImplementation("io.github.cottonmc:cotton-client-commands:1.0.0+1.15.2")
 }

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/ViaFabric.java

@@ -0,0 +1,115 @@
+package com.viaversion.fabric.mc116;
+
+import com.viaversion.fabric.mc116.commands.VRCommandHandler;
+import com.viaversion.fabric.mc116.config.VRConfig;
+import com.viaversion.fabric.mc116.platform.VRInjector;
+import com.viaversion.fabric.mc116.platform.VRLoader;
+import com.viaversion.fabric.mc116.platform.VRPlatform;
+import com.viaversion.fabric.mc116.protocol.ViaFabricHostnameProtocol;
+import com.viaversion.fabric.mc116.util.JLoggerToLog4j;
+import com.google.common.collect.Range;
+import com.google.common.util.concurrent.ThreadFactoryBuilder;
+import com.mojang.brigadier.arguments.StringArgumentType;
+import com.mojang.brigadier.builder.LiteralArgumentBuilder;
+import com.mojang.brigadier.builder.RequiredArgumentBuilder;
+import io.netty.channel.DefaultEventLoop;
+import io.netty.channel.EventLoop;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.api.ModInitializer;
+import net.fabricmc.fabric.api.client.command.v1.ClientCommandManager;
+import net.fabricmc.fabric.api.command.v1.CommandRegistrationCallback;
+import net.fabricmc.fabric.api.registry.CommandRegistry;
+import net.fabricmc.loader.api.FabricLoader;
+import net.minecraft.command.CommandSource;
+import org.apache.logging.log4j.LogManager;
+import com.viaversion.viaversion.ViaManagerImpl;
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.data.MappingDataLoader;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ThreadFactory;
+import java.util.logging.Logger;
+
+public class ViaFabric implements ModInitializer {
+    public static final Logger JLOGGER = new JLoggerToLog4j(LogManager.getLogger("ViaFabric"));
+    public static final ExecutorService ASYNC_EXECUTOR;
+    public static final EventLoop EVENT_LOOP;
+    public static CompletableFuture<Void> INIT_FUTURE = new CompletableFuture<>();
+    public static VRConfig config;
+
+    static {
+        ThreadFactory factory = new ThreadFactoryBuilder().setDaemon(true).setNameFormat("ViaFabric-%d").build();
+        ASYNC_EXECUTOR = Executors.newFixedThreadPool(8, factory);
+        EVENT_LOOP = new DefaultEventLoop(factory);
+        EVENT_LOOP.submit(INIT_FUTURE::join); // https://github.com/ViaVersion/ViaFabric/issues/53 ugly workaround code but works tm
+    }
+
+    public static String getVersion() {
+        return FabricLoader.getInstance().getModContainer("viafabric")
+                .get().getMetadata().getVersion().getFriendlyString();
+    }
+
+    public static <S extends CommandSource> LiteralArgumentBuilder<S> command(String commandName) {
+        return LiteralArgumentBuilder.<S>literal(commandName)
+                .then(
+                        RequiredArgumentBuilder
+                                .<S, String>argument("args", StringArgumentType.greedyString())
+                                .executes(((VRCommandHandler) Via.getManager().getCommandHandler())::execute)
+                                .suggests(((VRCommandHandler) Via.getManager().getCommandHandler())::suggestion)
+                )
+                .executes(((VRCommandHandler) Via.getManager().getCommandHandler())::execute);
+    }
+
+    @Override
+    public void onInitialize() {
+        Via.init(ViaManagerImpl.builder()
+                .injector(new VRInjector())
+                .loader(new VRLoader())
+                .commandHandler(new VRCommandHandler())
+                .platform(new VRPlatform()).build());
+
+        FabricLoader.getInstance().getModContainer("viabackwards").ifPresent(mod -> MappingDataLoader.enableMappingsCache());
+
+        ((ViaManagerImpl) Via.getManager()).init();
+
+        Via.getManager().getProtocolManager().registerBaseProtocol(ViaFabricHostnameProtocol.INSTANCE, Range.lessThan(Integer.MIN_VALUE));
+        ProtocolVersion.register(-2, "AUTO");
+
+        FabricLoader.getInstance().getEntrypoints("viafabric:via_api_initialized", Runnable.class).forEach(Runnable::run);
+
+        try {
+            registerCommandsV1();
+        } catch (NoClassDefFoundError ignored) {
+            try {
+                registerCommandsV0();
+                JLOGGER.info("Using Fabric Commands V0");
+            } catch (NoClassDefFoundError ignored2) {
+                JLOGGER.info("Couldn't register command as Fabric Commands isn't installed");
+            }
+        }
+
+        config = new VRConfig(FabricLoader.getInstance().getConfigDir().resolve("ViaFabric")
+                .resolve("viafabric.yml").toFile());
+
+        INIT_FUTURE.complete(null);
+    }
+
+    private void registerCommandsV1() {
+        CommandRegistrationCallback.EVENT.register((dispatcher, dedicated) -> dispatcher.register(command("viaversion")));
+        CommandRegistrationCallback.EVENT.register((dispatcher, dedicated) -> dispatcher.register(command("viaver")));
+        CommandRegistrationCallback.EVENT.register((dispatcher, dedicated) -> dispatcher.register(command("vvfabric")));
+        if (FabricLoader.getInstance().getEnvironmentType() == EnvType.CLIENT) {
+            ClientCommandManager.DISPATCHER.register(command("viafabricclient"));
+        }
+    }
+
+    @SuppressWarnings("deprecation")
+    private void registerCommandsV0() {
+        CommandRegistry.INSTANCE.register(false, dispatcher -> dispatcher.register(command("viaversion")));
+        CommandRegistry.INSTANCE.register(false, dispatcher -> dispatcher.register(command("viaver")));
+        CommandRegistry.INSTANCE.register(false, dispatcher -> dispatcher.register(command("vvfabric")));
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/ViaFabricAddress.java

@@ -0,0 +1,77 @@
+package com.viaversion.fabric.mc116;
+
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+
+import java.util.Locale;
+
+public class ViaFabricAddress {
+    public int protocol = 0;
+    public String viaSuffix = null;
+    public String realAddress = null;
+
+    public ViaFabricAddress parse(String address) {
+        if (address == null) return null;
+        String[] parts = address.split("\\.");
+
+        boolean foundDomain = false;
+        boolean foundOptions = false;
+
+        StringBuilder ourParts = new StringBuilder();
+        StringBuilder realAddrBuilder = new StringBuilder();
+
+        for (int i = parts.length - 1; i >= 0; i--) {
+            String part = parts[i];
+            boolean realAddrPart = false;
+            if (foundDomain) {
+                if (!foundOptions) {
+                    if (part.startsWith("_")) {
+                        String arg = part.substring(2);
+                        if (part.toLowerCase(Locale.ROOT).startsWith("_v")) {
+                            try {
+                                protocol = Integer.parseInt(arg);
+                            } catch (NumberFormatException e) {
+                                ProtocolVersion closest = ProtocolVersion.getClosest(arg.replace("_", "."));
+                                if (closest != null) {
+                                    protocol = closest.getVersion();
+                                }
+                            }
+                        }
+                    } else {
+                        foundOptions = true;
+                    }
+                }
+                if (foundOptions) {
+                    realAddrPart = true;
+                }
+            } else if (part.equalsIgnoreCase("viafabric")) {
+                foundDomain = true;
+            }
+            if (realAddrPart) {
+                realAddrBuilder.insert(0, part + ".");
+            } else {
+                ourParts.insert(0, part + ".");
+            }
+        }
+
+        String realAddr = realAddrBuilder.toString().replaceAll("\\.$", "");
+        String suffix = ourParts.toString().replaceAll("\\.$", "");
+
+        if (realAddr.isEmpty()) {
+            this.realAddress = address;
+        } else {
+            this.realAddress = realAddr;
+            this.viaSuffix = suffix;
+        }
+
+        return this;
+    }
+
+    @Override
+    public String toString() {
+        return "ViaFabricAddress{" +
+                "protocol=" + protocol +
+                ", viaSuffix='" + viaSuffix + '\'' +
+                ", realAddress='" + realAddress + '\'' +
+                '}';
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/commands/NMSCommandSender.java

@@ -0,0 +1,61 @@
+package com.viaversion.fabric.mc116.commands;
+
+import com.viaversion.fabric.mc116.platform.VRPlatform;
+import net.fabricmc.fabric.api.client.command.v1.FabricClientCommandSource;
+import net.minecraft.command.CommandSource;
+import net.minecraft.entity.Entity;
+import net.minecraft.server.command.ServerCommandSource;
+import net.minecraft.text.Text;
+import com.viaversion.viaversion.api.command.ViaCommandSender;
+import com.viaversion.viaversion.libs.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
+import com.viaversion.viaversion.libs.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
+
+import java.util.UUID;
+
+public class NMSCommandSender implements ViaCommandSender {
+    private final CommandSource source;
+
+    public NMSCommandSender(CommandSource source) {
+        this.source = source;
+    }
+
+    @Override
+    public boolean hasPermission(String s) {
+        // https://gaming.stackexchange.com/questions/138602/what-does-op-permission-level-do
+        return source.hasPermissionLevel(3);
+    }
+
+    @Override
+    public void sendMessage(String s) {
+        if (source instanceof ServerCommandSource) {
+            ((ServerCommandSource) source).sendFeedback(Text.Serializer.fromJson(VRPlatform.legacyToJson(s)), false);
+        } else if (source instanceof FabricClientCommandSource) {
+            ((FabricClientCommandSource) source).sendFeedback(Text.Serializer.fromJson(VRPlatform.legacyToJson(s)));
+        }
+    }
+
+    private String legacyToJson(String legacy) {
+        return GsonComponentSerializer.gson().serialize(LegacyComponentSerializer.legacySection().deserialize(legacy));
+    }
+
+    @Override
+    public UUID getUUID() {
+        if (source instanceof ServerCommandSource) {
+            Entity entity = ((ServerCommandSource) source).getEntity();
+            if (entity != null) return entity.getUuid();
+        } else if (source instanceof FabricClientCommandSource) {
+            return ((FabricClientCommandSource) source).getPlayer().getUuid();
+        }
+        return UUID.fromString(getName());
+    }
+
+    @Override
+    public String getName() {
+        if (source instanceof ServerCommandSource) {
+            return ((ServerCommandSource) source).getName();
+        } else if (source instanceof FabricClientCommandSource) {
+            return ((FabricClientCommandSource) source).getPlayer().getEntityName();
+        }
+        return "?";
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/commands/UserCommandSender.java

@@ -0,0 +1,35 @@
+package com.viaversion.fabric.mc116.commands;
+
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.command.ViaCommandSender;
+import com.viaversion.viaversion.api.connection.UserConnection;
+
+import java.util.UUID;
+
+public class UserCommandSender implements ViaCommandSender {
+    private UserConnection con;
+
+    public UserCommandSender(UserConnection con) {
+        this.con = con;
+    }
+
+    @Override
+    public boolean hasPermission(String s) {
+        return false;
+    }
+
+    @Override
+    public void sendMessage(String s) {
+        Via.getPlatform().sendMessage(getUUID(), s);
+    }
+
+    @Override
+    public UUID getUUID() {
+        return con.getProtocolInfo().getUuid();
+    }
+
+    @Override
+    public String getName() {
+        return con.getProtocolInfo().getUsername();
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/commands/VRCommandHandler.java

@@ -0,0 +1,55 @@
+package com.viaversion.fabric.mc116.commands;
+
+import com.viaversion.fabric.mc116.commands.subs.LeakDetectSubCommand;
+import com.mojang.brigadier.arguments.StringArgumentType;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.suggestion.Suggestions;
+import com.mojang.brigadier.suggestion.SuggestionsBuilder;
+import net.minecraft.command.CommandSource;
+import com.viaversion.viaversion.commands.ViaCommandHandler;
+
+import java.util.concurrent.CompletableFuture;
+
+public class VRCommandHandler extends ViaCommandHandler {
+    {
+        try {
+            registerSubCommand(new LeakDetectSubCommand());
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+
+    public int execute(CommandContext<? extends CommandSource> ctx) {
+        String[] args = new String[0];
+        try {
+            args = StringArgumentType.getString(ctx, "args").split(" ");
+        } catch (IllegalArgumentException ignored) {
+        }
+        onCommand(
+                new NMSCommandSender(ctx.getSource()),
+                args
+        );
+        return 1;
+    }
+
+    public CompletableFuture<Suggestions> suggestion(CommandContext<? extends CommandSource> ctx, SuggestionsBuilder builder) {
+        String[] args;
+        try {
+            args = StringArgumentType.getString(ctx, "args").split(" ", -1);
+        } catch (IllegalArgumentException ignored) {
+            args = new String[]{""};
+        }
+        String[] pref = args.clone();
+        pref[pref.length - 1] = "";
+        String prefix = String.join(" ", pref);
+        onTabComplete(new NMSCommandSender(ctx.getSource()), args)
+                .stream()
+                .map(it -> {
+                    SuggestionsBuilder b = new SuggestionsBuilder(builder.getInput(), prefix.length() + builder.getStart());
+                    b.suggest(it);
+                    return b;
+                })
+                .forEach(builder::add);
+        return builder.buildFuture();
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/commands/subs/LeakDetectSubCommand.java

@@ -0,0 +1,48 @@
+package com.viaversion.fabric.mc116.commands.subs;
+
+import io.netty.util.ResourceLeakDetector;
+import com.viaversion.viaversion.api.command.ViaCommandSender;
+import com.viaversion.viaversion.api.command.ViaSubCommand;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class LeakDetectSubCommand extends ViaSubCommand {
+    @Override
+    public String name() {
+        return "leakdetect";
+    }
+
+    @Override
+    public String description() {
+        return "Sets ResourceLeakDetector level";
+    }
+
+    @Override
+    public boolean execute(ViaCommandSender viaCommandSender, String[] strings) {
+        if (strings.length == 1) {
+            try {
+                ResourceLeakDetector.Level level = ResourceLeakDetector.Level.valueOf(strings[0]);
+                ResourceLeakDetector.setLevel(level);
+                viaCommandSender.sendMessage("Set leak detector level to " + level);
+            } catch (IllegalArgumentException e) {
+                viaCommandSender.sendMessage("Invalid level (" + Arrays.toString(ResourceLeakDetector.Level.values()) + ")");
+            }
+        } else {
+            viaCommandSender.sendMessage("Current leak detection level is " + ResourceLeakDetector.getLevel());
+        }
+        return true;
+    }
+
+    @Override
+    public List<String> onTabComplete(ViaCommandSender sender, String[] args) {
+        if (args.length == 1) {
+            return Arrays.stream(ResourceLeakDetector.Level.values())
+                    .map(Enum::name)
+                    .filter(it -> it.startsWith(args[0]))
+                    .collect(Collectors.toList());
+        }
+        return super.onTabComplete(sender, args);
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/config/VRConfig.java

@@ -0,0 +1,68 @@
+package com.viaversion.fabric.mc116.config;
+
+import com.viaversion.viaversion.util.Config;
+
+import java.io.File;
+import java.net.URL;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+
+public class VRConfig extends Config {
+    public static final String ENABLE_CLIENT_SIDE = "enable-client-side";
+    public static final String CLIENT_SIDE_VERSION = "client-side-version";
+    public static final String CLIENT_SIDE_FORCE_DISABLE = "client-side-force-disable";
+    public static final String HIDE_BUTTON = "hide-button";
+
+    public VRConfig(File configFile) {
+        super(configFile);
+        reloadConfig();
+    }
+
+    @Override
+    public URL getDefaultConfigURL() {
+        return getClass().getClassLoader().getResource("assets/viafabric/config.yml");
+    }
+
+    @Override
+    protected void handleConfig(Map<String, Object> map) {
+    }
+
+    @Override
+    public List<String> getUnsupportedOptions() {
+        return Collections.emptyList();
+    }
+
+    public boolean isClientSideEnabled() {
+        return getBoolean(ENABLE_CLIENT_SIDE, false);
+    }
+
+    public void setClientSideEnabled(boolean val) {
+        set(ENABLE_CLIENT_SIDE, val);
+    }
+
+    public int getClientSideVersion() {
+        return getInt(CLIENT_SIDE_VERSION, -1);
+    }
+
+    public void setClientSideVersion(int val) {
+        set(CLIENT_SIDE_VERSION, val);
+    }
+
+    public Collection<?> getClientSideForceDisable() {
+        return (List<?>) get(CLIENT_SIDE_FORCE_DISABLE, List.class, Collections.emptyList());
+    }
+
+    public void setHideButton(boolean val) {
+        set(HIDE_BUTTON, val);
+    }
+
+    public boolean isHideButton() {
+        return getBoolean(HIDE_BUTTON, false);
+    }
+
+    public boolean isForcedDisable(String line) {
+        return getClientSideForceDisable().contains(line);
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/gui/ModMenuConfig.java

@@ -0,0 +1,11 @@
+package com.viaversion.fabric.mc116.gui;
+
+import io.github.prospector.modmenu.api.ConfigScreenFactory;
+import io.github.prospector.modmenu.api.ModMenuApi;
+
+public class ModMenuConfig implements ModMenuApi {
+    @Override
+    public ConfigScreenFactory<?> getModConfigScreenFactory() {
+        return ViaConfigScreen::new;
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/gui/ViaConfigScreen.java

@@ -0,0 +1,171 @@
+package com.viaversion.fabric.mc116.gui;
+
+import com.viaversion.fabric.mc116.ViaFabric;
+import com.viaversion.fabric.mc116.util.ProtocolUtils;
+import com.viaversion.viaversion.api.Via;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.api.Environment;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.gui.screen.ConfirmScreen;
+import net.minecraft.client.gui.screen.Screen;
+import net.minecraft.client.gui.screen.ScreenTexts;
+import net.minecraft.client.gui.widget.ButtonWidget;
+import net.minecraft.client.gui.widget.TextFieldWidget;
+import net.minecraft.client.util.math.MatrixStack;
+import net.minecraft.text.TranslatableText;
+
+import java.util.concurrent.CompletableFuture;
+
+@Environment(EnvType.CLIENT)
+public class ViaConfigScreen extends Screen {
+    private static CompletableFuture<Void> latestProtocolSave;
+    private final Screen parent;
+    private TextFieldWidget protocolVersion;
+
+    public ViaConfigScreen(Screen parent) {
+        super(new TranslatableText("gui.viafabric_config.title"));
+        this.parent = parent;
+    }
+
+    private static int getProtocolTextColor(boolean valid, boolean supported) {
+
+        if (!valid) {
+            return 0xff0000; // Red
+        } else if (!supported) {
+            return 0xFFA500; // Orange
+        }
+        return 0xE0E0E0; // Default
+    }
+
+    @Override
+    protected void init() {
+        int entries = 0;
+
+        this.addButton(new ButtonWidget(this.width / 2 - 155 + entries % 2 * 160,
+                this.height / 6 + 24 * (entries >> 1),
+                150,
+                20, getClientSideText(), this::onClickClientSide));
+        entries++;
+
+        this.addButton(new ButtonWidget(this.width / 2 - 155 + entries % 2 * 160,
+                this.height / 6 + 24 * (entries >> 1),
+                150,
+                20, getHideViaButtonText(), this::onHideViaButton));
+        entries++;
+
+        protocolVersion = new TextFieldWidget(this.textRenderer,
+                this.width / 2 - 155 + entries % 2 * 160,
+                this.height / 6 + 24 * (entries >> 1),
+                150,
+                20, new TranslatableText("gui.protocol_version_field.name"));
+        entries++;
+
+        protocolVersion.setTextPredicate(ProtocolUtils::isStartOfProtocolText);
+        protocolVersion.setChangedListener(this::onChangeVersionField);
+        int clientSideVersion = ViaFabric.config.getClientSideVersion();
+        protocolVersion.setText(ProtocolUtils.getProtocolName(clientSideVersion));
+
+        this.children.add(protocolVersion);
+
+        //noinspection ConstantConditions
+        if (entries % 2 == 1) {
+            entries++;
+        }
+
+        this.addButton(new ButtonWidget(this.width / 2 - 100, this.height / 6 + 24 * (entries >> 1), 200, 20, ScreenTexts.DONE, (buttonWidget) -> this.client.openScreen(this.parent)));
+    }
+
+    private void onChangeVersionField(String text) {
+        protocolVersion.setSuggestion(null);
+        int newVersion = ViaFabric.config.getClientSideVersion();
+
+        Integer parsed = ProtocolUtils.parseProtocolId(text);
+        boolean validProtocol;
+
+        if (parsed != null) {
+            newVersion = parsed;
+            validProtocol = true;
+        } else {
+            validProtocol = false;
+            String[] suggestions = ProtocolUtils.getProtocolSuggestions(text);
+            if (suggestions.length == 1) {
+                protocolVersion.setSuggestion(suggestions[0].substring(text.length()));
+            }
+        }
+
+        protocolVersion.setEditableColor(
+                getProtocolTextColor(ProtocolUtils.isSupported(newVersion, Via.getAPI().getServerVersion().lowestSupportedVersion()),
+                        validProtocol));
+
+        int finalNewVersion = newVersion;
+        if (latestProtocolSave == null) latestProtocolSave = CompletableFuture.completedFuture(null);
+        ViaFabric.config.setClientSideVersion(finalNewVersion);
+        latestProtocolSave = latestProtocolSave.thenRunAsync(ViaFabric.config::saveConfig, ViaFabric.ASYNC_EXECUTOR);
+    }
+
+    private void onClickClientSide(ButtonWidget widget) {
+        if (!ViaFabric.config.isClientSideEnabled()) {
+            MinecraftClient.getInstance().openScreen(new ConfirmScreen(
+                    answer -> {
+                        if (answer) {
+                            ViaFabric.config.setClientSideEnabled(true);
+                            ViaFabric.config.setClientSideVersion(-2); // AUTO
+                            ViaFabric.config.saveConfig();
+                            widget.setMessage(getClientSideText());
+                        }
+                        MinecraftClient.getInstance().openScreen(this);
+                    },
+                    new TranslatableText("gui.enable_client_side.question"),
+                    new TranslatableText("gui.enable_client_side.warning"),
+                    new TranslatableText("gui.enable_client_side.enable"),
+                    new TranslatableText("gui.cancel")
+            ));
+        } else {
+            ViaFabric.config.setClientSideEnabled(false);
+            ViaFabric.config.saveConfig();
+        }
+        widget.setMessage(getClientSideText());
+    }
+
+    @Override
+    public void removed() {
+        ViaFabric.config.saveConfig();
+    }
+
+    @Override
+    public void onClose() {
+        this.client.openScreen(this.parent);
+    }
+
+    private TranslatableText getClientSideText() {
+        return ViaFabric.config.isClientSideEnabled() ?
+                new TranslatableText("gui.client_side.disable")
+                : new TranslatableText("gui.client_side.enable");
+    }
+
+    private TranslatableText getHideViaButtonText() {
+        return ViaFabric.config.isHideButton() ?
+                new TranslatableText("gui.hide_via_button.disable") : new TranslatableText("gui.hide_via_button.enable");
+    }
+
+    private void onHideViaButton(ButtonWidget widget) {
+        ViaFabric.config.setHideButton(!ViaFabric.config.isHideButton());
+        ViaFabric.config.saveConfig();
+        widget.setMessage(getHideViaButtonText());
+    }
+
+    @Override
+    public void render(MatrixStack matrices, int mouseX, int mouseY, float delta) {
+        this.renderBackground(matrices);
+        drawCenteredText(matrices, this.textRenderer, this.title, this.width / 2, 20, 16777215);
+        super.render(matrices, mouseX, mouseY, delta);
+        protocolVersion.render(matrices, mouseX, mouseY, delta);
+    }
+
+    @Override
+    public void tick() {
+        super.tick();
+        protocolVersion.tick();
+    }
+}
+

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/handler/CommonTransformer.java

@@ -0,0 +1,38 @@
+package com.viaversion.fabric.mc116.handler;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandler;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.ByteToMessageDecoder;
+import io.netty.handler.codec.MessageToByteEncoder;
+import io.netty.handler.codec.MessageToMessageDecoder;
+import com.viaversion.viaversion.util.PipelineUtil;
+
+import java.lang.reflect.InvocationTargetException;
+
+public class CommonTransformer {
+    public static final String HANDLER_DECODER_NAME = "via-decoder";
+    public static final String HANDLER_ENCODER_NAME = "via-encoder";
+
+    public static void decompress(ChannelHandlerContext ctx, ByteBuf buf) throws InvocationTargetException {
+        ChannelHandler handler = ctx.pipeline().get("decompress");
+        ByteBuf decompressed = handler instanceof MessageToMessageDecoder
+                ? (ByteBuf) PipelineUtil.callDecode((MessageToMessageDecoder<?>) handler, ctx, buf).get(0)
+                : (ByteBuf) PipelineUtil.callDecode((ByteToMessageDecoder) handler, ctx, buf).get(0);
+        try {
+            buf.clear().writeBytes(decompressed);
+        } finally {
+            decompressed.release();
+        }
+    }
+
+    public static void compress(ChannelHandlerContext ctx, ByteBuf buf) throws Exception {
+        ByteBuf compressed = ctx.alloc().buffer();
+        try {
+            PipelineUtil.callEncode((MessageToByteEncoder<?>) ctx.pipeline().get("compress"), ctx, buf, compressed);
+            buf.clear().writeBytes(compressed);
+        } finally {
+            compressed.release();
+        }
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/handler/FabricDecodeHandler.java

@@ -0,0 +1,85 @@
+package com.viaversion.fabric.mc116.handler;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandler;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.MessageToMessageDecoder;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.exception.CancelCodecException;
+import com.viaversion.viaversion.exception.CancelDecoderException;
+import com.viaversion.viaversion.util.PipelineUtil;
+
+import java.lang.reflect.InvocationTargetException;
+import java.util.List;
+
+@ChannelHandler.Sharable
+public class FabricDecodeHandler extends MessageToMessageDecoder<ByteBuf> {
+    private final UserConnection info;
+    private boolean handledCompression;
+    private boolean skipDoubleTransform;
+
+    public FabricDecodeHandler(UserConnection info) {
+        this.info = info;
+    }
+
+    public UserConnection getInfo() {
+        return info;
+    }
+
+    // https://github.com/ViaVersion/ViaVersion/blob/master/velocity/src/main/java/us/myles/ViaVersion/velocity/handlers/VelocityDecodeHandler.java
+    @Override
+    protected void decode(ChannelHandlerContext ctx, ByteBuf bytebuf, List<Object> out) throws Exception {
+        if (skipDoubleTransform) {
+            skipDoubleTransform = false;
+            out.add(bytebuf.retain());
+            return;
+        }
+
+        if (!info.checkIncomingPacket()) throw CancelDecoderException.generate(null);
+        if (!info.shouldTransformPacket()) {
+            out.add(bytebuf.retain());
+            return;
+        }
+
+        ByteBuf transformedBuf = ctx.alloc().buffer().writeBytes(bytebuf);
+        try {
+            boolean needsCompress = handleCompressionOrder(ctx, transformedBuf);
+
+            info.transformIncoming(transformedBuf, CancelDecoderException::generate);
+
+            if (needsCompress) {
+                CommonTransformer.compress(ctx, transformedBuf);
+                skipDoubleTransform = true;
+            }
+            out.add(transformedBuf.retain());
+        } finally {
+            transformedBuf.release();
+        }
+    }
+
+    private boolean handleCompressionOrder(ChannelHandlerContext ctx, ByteBuf buf) throws InvocationTargetException {
+        if (handledCompression) return false;
+
+        int decoderIndex = ctx.pipeline().names().indexOf("decompress");
+        if (decoderIndex == -1) return false;
+        handledCompression = true;
+        if (decoderIndex > ctx.pipeline().names().indexOf("via-decoder")) {
+            // Need to decompress this packet due to bad order
+            CommonTransformer.decompress(ctx, buf);
+            ChannelHandler encoder = ctx.pipeline().get("via-encoder");
+            ChannelHandler decoder = ctx.pipeline().get("via-decoder");
+            ctx.pipeline().remove(encoder);
+            ctx.pipeline().remove(decoder);
+            ctx.pipeline().addAfter("compress", "via-encoder", encoder);
+            ctx.pipeline().addAfter("decompress", "via-decoder", decoder);
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+        if (PipelineUtil.containsCause(cause, CancelCodecException.class)) return;
+        super.exceptionCaught(ctx, cause);
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/handler/FabricEncodeHandler.java

@@ -0,0 +1,72 @@
+package com.viaversion.fabric.mc116.handler;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandler;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.MessageToMessageEncoder;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.exception.CancelCodecException;
+import com.viaversion.viaversion.exception.CancelEncoderException;
+import com.viaversion.viaversion.util.PipelineUtil;
+
+import java.lang.reflect.InvocationTargetException;
+import java.util.List;
+
+@ChannelHandler.Sharable
+public class FabricEncodeHandler extends MessageToMessageEncoder<ByteBuf> {
+    private final UserConnection info;
+    private boolean handledCompression;
+
+    public FabricEncodeHandler(UserConnection info) {
+        this.info = info;
+    }
+
+    @Override
+    protected void encode(final ChannelHandlerContext ctx, ByteBuf bytebuf, List<Object> out) throws Exception {
+        if (!info.checkOutgoingPacket()) throw CancelEncoderException.generate(null);
+        if (!info.shouldTransformPacket()) {
+            out.add(bytebuf.retain());
+            return;
+        }
+
+        ByteBuf transformedBuf = ctx.alloc().buffer().writeBytes(bytebuf);
+        try {
+            boolean needsCompress = handleCompressionOrder(ctx, transformedBuf);
+
+            info.transformOutgoing(transformedBuf, CancelEncoderException::generate);
+
+            if (needsCompress) {
+                CommonTransformer.compress(ctx, transformedBuf);
+            }
+            out.add(transformedBuf.retain());
+        } finally {
+            transformedBuf.release();
+        }
+    }
+
+    private boolean handleCompressionOrder(ChannelHandlerContext ctx, ByteBuf buf) throws InvocationTargetException {
+        if (handledCompression) return false;
+
+        int encoderIndex = ctx.pipeline().names().indexOf("compress");
+        if (encoderIndex == -1) return false;
+        handledCompression = true;
+        if (encoderIndex > ctx.pipeline().names().indexOf("via-encoder")) {
+            // Need to decompress this packet due to bad order
+            CommonTransformer.decompress(ctx, buf);
+            ChannelHandler encoder = ctx.pipeline().get("via-encoder");
+            ChannelHandler decoder = ctx.pipeline().get("via-decoder");
+            ctx.pipeline().remove(encoder);
+            ctx.pipeline().remove(decoder);
+            ctx.pipeline().addAfter("compress", "via-encoder", encoder);
+            ctx.pipeline().addAfter("decompress", "via-decoder", decoder);
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+        if (PipelineUtil.containsCause(cause, CancelCodecException.class)) return;
+        super.exceptionCaught(ctx, cause);
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/handler/clientside/ProtocolDetectionHandler.java

@@ -0,0 +1,79 @@
+package com.viaversion.fabric.mc116.handler.clientside;
+
+import com.viaversion.fabric.mc116.ViaFabric;
+import com.viaversion.fabric.mc116.service.ProtocolAutoDetector;
+import com.viaversion.viaversion.util.Pair;
+import io.netty.channel.ChannelDuplexHandler;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelPromise;
+
+import java.net.InetSocketAddress;
+import java.util.ArrayDeque;
+import java.util.Queue;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.TimeUnit;
+
+public class ProtocolDetectionHandler extends ChannelDuplexHandler {
+    private final Queue<Pair<Object, ChannelPromise>> queuedMessages = new ArrayDeque<>();
+    private boolean hold = true;
+    private boolean pendentFlush;
+
+    @Override
+    public void channelActive(ChannelHandlerContext ctx) throws Exception {
+        super.channelActive(ctx);
+        if (ctx.channel().remoteAddress() instanceof InetSocketAddress) {
+            ScheduledFuture<?> timeoutRun = ctx.executor().schedule(() -> {
+                ViaFabric.JLOGGER.warning("Timeout for protocol auto-detection in "
+                        + ctx.channel().remoteAddress() + " server");
+                hold = false;
+                drainQueue(ctx);
+                ctx.pipeline().remove(this);
+            }, 10, TimeUnit.SECONDS);
+            ProtocolAutoDetector.detectVersion(((InetSocketAddress) ctx.channel().remoteAddress()))
+                    .whenComplete((obj, ex) -> {
+                        ctx.pipeline().remove(this);
+                        timeoutRun.cancel(false);
+                    });
+            // Let's cache it before we need it
+        }
+    }
+
+    @Override
+    public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception {
+        if (!hold) {
+            drainQueue(ctx);
+            super.write(ctx, msg, promise);
+        } else {
+            queuedMessages.add(new Pair<>(msg, promise));
+        }
+    }
+
+    @Override
+    public void flush(ChannelHandlerContext ctx) throws Exception {
+        if (!hold) {
+            drainQueue(ctx);
+            super.flush(ctx);
+        } else {
+            pendentFlush = true;
+        }
+    }
+
+    @Override
+    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
+        drainQueue(ctx);
+        super.channelInactive(ctx);
+    }
+
+    private void drainQueue(ChannelHandlerContext ctx) {
+        queuedMessages.forEach(it -> ctx.write(it.getKey(), it.getValue()));
+        queuedMessages.clear();
+        if (pendentFlush) ctx.flush();
+        pendentFlush = false;
+    }
+
+    @Override
+    public void handlerRemoved(ChannelHandlerContext ctx) throws Exception {
+        drainQueue(ctx);
+        super.handlerRemoved(ctx);
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/mixin/address/client/MixinConnectScreenThread.java

@@ -0,0 +1,24 @@
+package com.viaversion.fabric.mc116.mixin.address.client;
+
+import com.viaversion.fabric.mc116.ViaFabricAddress;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Redirect;
+
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
+@Mixin(targets = "net/minecraft/client/gui/screen/ConnectScreen$1", priority = 2000)
+public class MixinConnectScreenThread {
+    @Redirect(method = "run()V", at = @At(value = "INVOKE",
+            target = "Ljava/net/InetAddress;getByName(Ljava/lang/String;)Ljava/net/InetAddress;"))
+    private InetAddress resolveViaFabricAddr(String address) throws UnknownHostException {
+        ViaFabricAddress viaAddr = new ViaFabricAddress().parse(address);
+        if (viaAddr.viaSuffix == null) {
+            return InetAddress.getByName(address);
+        }
+
+        InetAddress resolved = InetAddress.getByName(viaAddr.realAddress);
+        return InetAddress.getByAddress(resolved.getHostName() + "." + viaAddr.viaSuffix, resolved.getAddress());
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/mixin/address/client/MixinServerAddress.java

@@ -0,0 +1,27 @@
+package com.viaversion.fabric.mc116.mixin.address.client;
+
+import com.viaversion.fabric.mc116.ViaFabricAddress;
+import com.mojang.datafixers.util.Pair;
+import net.minecraft.network.ServerAddress;
+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.Redirect;
+
+@Mixin(ServerAddress.class)
+public abstract class MixinServerAddress {
+    @Shadow
+    private static Pair<String, Integer> resolveServer(String address) {
+        throw new AssertionError();
+    }
+
+    @Redirect(method = "parse", at = @At(value = "INVOKE", target = "Lnet/minecraft/network/ServerAddress;resolveServer(Ljava/lang/String;)Lcom/mojang/datafixers/util/Pair;"))
+    private static Pair<String, Integer> modifySrvAddr(String address) {
+        ViaFabricAddress viaAddr = new ViaFabricAddress().parse(address);
+        if (viaAddr.viaSuffix == null) {
+            return resolveServer(address);
+        }
+
+        return resolveServer(viaAddr.realAddress).mapFirst(it -> it.replaceAll("\\.$", "") + "." + viaAddr.viaSuffix);
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/mixin/address/client/MixinServerPinger.java

@@ -0,0 +1,25 @@
+package com.viaversion.fabric.mc116.mixin.address.client;
+
+import com.viaversion.fabric.mc116.ViaFabricAddress;
+import net.minecraft.client.network.MultiplayerServerListPinger;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Redirect;
+
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
+@Mixin(MultiplayerServerListPinger.class)
+public class MixinServerPinger {
+    @Redirect(method = "add", at = @At(value = "INVOKE",
+            target = "Ljava/net/InetAddress;getByName(Ljava/lang/String;)Ljava/net/InetAddress;"))
+    private InetAddress resolveViaFabricAddr(String address) throws UnknownHostException {
+        ViaFabricAddress viaAddr = new ViaFabricAddress().parse(address);
+        if (viaAddr.viaSuffix == null) {
+            return InetAddress.getByName(address);
+        }
+
+        InetAddress resolved = InetAddress.getByName(viaAddr.realAddress);
+        return InetAddress.getByAddress(resolved.getHostName() + "." + viaAddr.viaSuffix, resolved.getAddress());
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/mixin/debug/client/MixinClientConnectionAccessor.java

@@ -0,0 +1,12 @@
+package com.viaversion.fabric.mc116.mixin.debug.client;
+
+import io.netty.channel.Channel;
+import net.minecraft.network.ClientConnection;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.gen.Accessor;
+
+@Mixin(ClientConnection.class)
+public interface MixinClientConnectionAccessor {
+    @Accessor
+    Channel getChannel();
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/mixin/debug/client/MixinDebugHud.java

@@ -0,0 +1,38 @@
+package com.viaversion.fabric.mc116.mixin.debug.client;
+
+import com.viaversion.fabric.mc116.handler.CommonTransformer;
+import com.viaversion.fabric.mc116.handler.FabricDecodeHandler;
+import com.viaversion.viaversion.api.connection.ProtocolInfo;
+import io.netty.channel.ChannelHandler;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.gui.hud.DebugHud;
+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;
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+
+import java.util.List;
+
+@Mixin(DebugHud.class)
+public class MixinDebugHud {
+    @Inject(at = @At("RETURN"), method = "getLeftText")
+    protected void getLeftText(CallbackInfoReturnable<List<String>> info) {
+        String line = "[ViaFabric] I: " + Via.getManager().getConnectionManager().getConnections().size() + " (F: "
+                + Via.getManager().getConnectionManager().getConnectedClients().size() + ")";
+        @SuppressWarnings("ConstantConditions") ChannelHandler viaDecoder = ((MixinClientConnectionAccessor) MinecraftClient.getInstance().getNetworkHandler()
+                .getConnection()).getChannel().pipeline().get(CommonTransformer.HANDLER_DECODER_NAME);
+        if (viaDecoder instanceof FabricDecodeHandler) {
+            ProtocolInfo protocol = ((FabricDecodeHandler) viaDecoder).getInfo().getProtocolInfo();
+            if (protocol != null) {
+                ProtocolVersion serverVer = ProtocolVersion.getProtocol(protocol.getServerProtocolVersion());
+                ProtocolVersion clientVer = ProtocolVersion.getProtocol(protocol.getProtocolVersion());
+                line += " / C: " + clientVer.getName() + " (" + clientVer.getVersion() + ") S: "
+                        + serverVer.getName() + " (" + serverVer.getVersion() + ") A: " + protocol.getUser().isActive();
+            }
+        }
+
+        info.getReturnValue().add(line);
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/mixin/gui/client/MixinMultiplayerScreen.java

@@ -0,0 +1,38 @@
+package com.viaversion.fabric.mc116.mixin.gui.client;
+
+import com.viaversion.fabric.mc116.ViaFabric;
+import com.viaversion.fabric.mc116.gui.ViaConfigScreen;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.gui.screen.Screen;
+import net.minecraft.client.gui.screen.multiplayer.MultiplayerScreen;
+import net.minecraft.client.gui.widget.ButtonWidget;
+import net.minecraft.client.gui.widget.TexturedButtonWidget;
+import net.minecraft.text.Text;
+import net.minecraft.text.TranslatableText;
+import net.minecraft.util.Identifier;
+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(MultiplayerScreen.class)
+public abstract class MixinMultiplayerScreen extends Screen {
+    protected MixinMultiplayerScreen(Text title, UnsupportedOperationException e) {
+        super(title);
+        throw e;
+    }
+
+    @Inject(method = "init", at = @At("TAIL"))
+    private void onInit(CallbackInfo ci) {
+        ButtonWidget enableClientSideViaVersion = new TexturedButtonWidget(this.width / 2 + 113, 10,
+                40, 20, // Size
+                0, 0, // Start pos of texture
+                20, // v Hover offset
+                new Identifier("viafabric:textures/gui/widgets.png"),
+                256, 256, // Texture size
+                it -> MinecraftClient.getInstance().openScreen(new ViaConfigScreen(this)),
+                new TranslatableText("gui.via_button"));
+        if (ViaFabric.config.isHideButton()) enableClientSideViaVersion.visible = false;
+        addButton(enableClientSideViaVersion);
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/mixin/pipeline/MixinClientConnection.java

@@ -0,0 +1,31 @@
+package com.viaversion.fabric.mc116.mixin.pipeline;
+
+import io.netty.channel.Channel;
+import net.minecraft.network.ClientConnection;
+import org.apache.logging.log4j.Logger;
+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.Redirect;
+
+
+@Mixin(ClientConnection.class)
+public class MixinClientConnection {
+    @Shadow
+    private Channel channel;
+
+    @Redirect(
+            method = "exceptionCaught",
+            remap = false,
+            at = @At(
+                    value = "INVOKE",
+                    target = "Lorg/apache/logging/log4j/Logger;debug(Ljava/lang/String;Ljava/lang/Throwable;)V"
+            ))
+    private void redirectDebug(Logger logger, String message, Throwable t) {
+        if ("Failed to sent packet".equals(message)) {
+            logger.info(message, t);
+        } else {
+            logger.debug(message, t);
+        }
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/mixin/pipeline/MixinServerNetworkIoChInit.java

@@ -0,0 +1,28 @@
+package com.viaversion.fabric.mc116.mixin.pipeline;
+
+import com.viaversion.fabric.mc116.handler.CommonTransformer;
+import com.viaversion.fabric.mc116.handler.FabricDecodeHandler;
+import com.viaversion.fabric.mc116.handler.FabricEncodeHandler;
+import com.viaversion.viaversion.connection.UserConnectionImpl;
+import com.viaversion.viaversion.protocol.ProtocolPipelineImpl;
+import io.netty.channel.Channel;
+import io.netty.channel.socket.SocketChannel;
+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;
+import com.viaversion.viaversion.api.connection.UserConnection;
+
+@Mixin(targets = "net.minecraft.server.ServerNetworkIo$1")
+public class MixinServerNetworkIoChInit {
+    @Inject(method = "initChannel", at = @At(value = "TAIL"), remap = false)
+    private void onInitChannel(Channel channel, CallbackInfo ci) {
+        if (channel instanceof SocketChannel) {
+            UserConnection user = new UserConnectionImpl(channel);
+            new ProtocolPipelineImpl(user);
+
+            channel.pipeline().addBefore("encoder", CommonTransformer.HANDLER_ENCODER_NAME, new FabricEncodeHandler(user));
+            channel.pipeline().addBefore("decoder", CommonTransformer.HANDLER_DECODER_NAME, new FabricDecodeHandler(user));
+        }
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/mixin/pipeline/client/MixinClientConnectionChInit.java

@@ -0,0 +1,35 @@
+package com.viaversion.fabric.mc116.mixin.pipeline.client;
+
+import com.viaversion.fabric.mc116.ViaFabric;
+import com.viaversion.fabric.mc116.handler.CommonTransformer;
+import com.viaversion.fabric.mc116.handler.FabricDecodeHandler;
+import com.viaversion.fabric.mc116.handler.FabricEncodeHandler;
+import com.viaversion.fabric.mc116.handler.clientside.ProtocolDetectionHandler;
+import com.viaversion.fabric.mc116.protocol.ViaFabricHostnameProtocol;
+import com.viaversion.viaversion.connection.UserConnectionImpl;
+import com.viaversion.viaversion.protocol.ProtocolPipelineImpl;
+import io.netty.channel.Channel;
+import io.netty.channel.socket.SocketChannel;
+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;
+import com.viaversion.viaversion.api.connection.UserConnection;
+
+@Mixin(targets = "net.minecraft.network.ClientConnection$1")
+public class MixinClientConnectionChInit {
+    @Inject(method = "initChannel", at = @At(value = "TAIL"), remap = false)
+    private void onInitChannel(Channel channel, CallbackInfo ci) {
+        if (channel instanceof SocketChannel) {
+            UserConnection user = new UserConnectionImpl(channel, true);
+            new ProtocolPipelineImpl(user).add(ViaFabricHostnameProtocol.INSTANCE);
+
+            channel.pipeline()
+                    .addBefore("encoder", CommonTransformer.HANDLER_ENCODER_NAME, new FabricEncodeHandler(user))
+                    .addBefore("decoder", CommonTransformer.HANDLER_DECODER_NAME, new FabricDecodeHandler(user));
+            if (ViaFabric.config.isClientSideEnabled()) {
+                channel.pipeline().addAfter(CommonTransformer.HANDLER_ENCODER_NAME, "via-autoprotocol", new ProtocolDetectionHandler());
+            }
+        }
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/platform/VRInjector.java

@@ -0,0 +1,61 @@
+package com.viaversion.fabric.mc116.platform;
+
+import com.viaversion.fabric.mc116.handler.CommonTransformer;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.loader.api.FabricLoader;
+import net.minecraft.SharedConstants;
+import com.viaversion.viaversion.api.platform.ViaInjector;
+import com.viaversion.viaversion.util.GsonUtil;
+import com.viaversion.viaversion.libs.gson.JsonObject;
+
+import java.lang.reflect.Method;
+import java.util.Arrays;
+
+public class VRInjector implements ViaInjector {
+    @Override
+    public void inject() {
+        // *looks at Mixins*
+    }
+
+    @Override
+    public void uninject() {
+        // not possible *plays sad violin*
+    }
+
+    @Override
+    public int getServerProtocolVersion() {
+        return SharedConstants.getGameVersion().getProtocolVersion();
+    }
+
+    @Override
+    public String getEncoderName() {
+        return CommonTransformer.HANDLER_ENCODER_NAME;
+    }
+
+    @Override
+    public String getDecoderName() {
+        return CommonTransformer.HANDLER_DECODER_NAME;
+    }
+
+    @Override
+    public JsonObject getDump() {
+        JsonObject obj = new JsonObject();
+        try {
+            obj.add("serverNetworkIOChInit", GsonUtil.getGson().toJsonTree(
+                    Arrays.stream(Class.forName("net.minecraft.class_3242$1").getDeclaredMethods())
+                            .map(Method::toString)
+                            .toArray(String[]::new)));
+        } catch (ClassNotFoundException ignored) {
+        }
+        if (FabricLoader.getInstance().getEnvironmentType() == EnvType.CLIENT) {
+            try {
+                obj.add("clientConnectionChInit", GsonUtil.getGson().toJsonTree(
+                        Arrays.stream(Class.forName("net.minecraft.class_2535$1").getDeclaredMethods())
+                                .map(Method::toString)
+                                .toArray(String[]::new)));
+            } catch (ClassNotFoundException ignored) {
+            }
+        }
+        return obj;
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/platform/VRLoader.java

@@ -0,0 +1,34 @@
+package com.viaversion.fabric.mc116.platform;
+
+import com.viaversion.fabric.mc116.providers.VRHandItemProvider;
+import com.viaversion.fabric.mc116.providers.VRVersionProvider;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.loader.api.FabricLoader;
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.platform.ViaPlatformLoader;
+import com.viaversion.viaversion.bungee.providers.BungeeMovementTransmitter;
+import com.viaversion.viaversion.api.protocol.version.VersionProvider;
+import com.viaversion.viaversion.protocols.protocol1_9to1_8.providers.HandItemProvider;
+import com.viaversion.viaversion.protocols.protocol1_9to1_8.providers.MovementTransmitterProvider;
+
+public class VRLoader implements ViaPlatformLoader {
+    @Override
+    public void load() {
+        Via.getManager().getProviders().use(MovementTransmitterProvider.class, new BungeeMovementTransmitter());
+        Via.getManager().getProviders().use(VersionProvider.class, new VRVersionProvider());
+
+        if (Via.getPlatform().getConf().isItemCache()) {
+            VRHandItemProvider handProvider = new VRHandItemProvider();
+            if (FabricLoader.getInstance().getEnvironmentType() == EnvType.CLIENT) {
+                handProvider.registerClientTick();
+            }
+            handProvider.registerServerTick();
+            Via.getManager().getProviders().use(HandItemProvider.class, handProvider);
+        }
+    }
+
+    @Override
+    public void unload() {
+        // Nothing to do
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/platform/VRPlatform.java

@@ -0,0 +1,273 @@
+package com.viaversion.fabric.mc116.platform;
+
+import com.viaversion.fabric.mc116.ViaFabric;
+import com.viaversion.fabric.mc116.commands.NMSCommandSender;
+import com.viaversion.fabric.mc116.commands.UserCommandSender;
+import com.viaversion.fabric.mc116.util.FutureTaskId;
+import com.viaversion.fabric.mc116.util.JLoggerToLog4j;
+import com.viaversion.viaversion.api.configuration.ViaVersionConfig;
+import com.viaversion.viaversion.api.platform.PlatformTask;
+import io.netty.util.concurrent.Future;
+import io.netty.util.concurrent.GenericFutureListener;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.api.Environment;
+import net.fabricmc.loader.api.FabricLoader;
+import net.fabricmc.loader.api.ModContainer;
+import net.fabricmc.loader.api.Version;
+import net.fabricmc.loader.api.metadata.ModMetadata;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.entity.Entity;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.minecraft.text.Text;
+import org.apache.logging.log4j.LogManager;
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.ViaAPI;
+import com.viaversion.viaversion.api.command.ViaCommandSender;
+import com.viaversion.viaversion.api.configuration.ConfigurationProvider;
+import com.viaversion.viaversion.api.platform.ViaPlatform;
+import com.viaversion.viaversion.dump.PluginInfo;
+import com.viaversion.viaversion.util.GsonUtil;
+import com.viaversion.viaversion.libs.gson.JsonObject;
+import com.viaversion.viaversion.libs.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
+import com.viaversion.viaversion.libs.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
+
+import java.io.File;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
+import java.util.concurrent.CancellationException;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.TimeUnit;
+import java.util.function.Supplier;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import java.util.stream.Collectors;
+
+public class VRPlatform implements ViaPlatform<UUID> {
+    private final Logger logger = new JLoggerToLog4j(LogManager.getLogger("ViaVersion"));
+    private final VRViaConfig config;
+    private final File dataFolder;
+    private final ViaAPI<UUID> api;
+
+    public VRPlatform() {
+        Path configDir = FabricLoader.getInstance().getConfigDirectory().toPath().resolve("ViaFabric");
+        config = new VRViaConfig(configDir.resolve("viaversion.yml").toFile());
+        dataFolder = configDir.toFile();
+        api = new VRViaAPI();
+    }
+
+    public static MinecraftServer getServer() {
+        if (FabricLoader.getInstance().getEnvironmentType() == EnvType.CLIENT) {
+            return getIntegratedServer();
+        }
+        return (MinecraftServer) FabricLoader.getInstance().getGameInstance();
+    }
+
+    @Environment(EnvType.CLIENT)
+    private static MinecraftServer getIntegratedServer() {
+        return MinecraftClient.getInstance().getServer();
+    }
+
+    public static String legacyToJson(String legacy) {
+        return GsonComponentSerializer.gson().serialize(LegacyComponentSerializer.legacySection().deserialize(legacy));
+    }
+
+    @Override
+    public Logger getLogger() {
+        return logger;
+    }
+
+    @Override
+    public String getPlatformName() {
+        return "ViaFabric";
+    }
+
+    @Override
+    public String getPlatformVersion() {
+        return ViaFabric.getVersion();
+    }
+
+    @Override
+    public String getPluginVersion() {
+        return FabricLoader.getInstance().getModContainer("viaversion").map(ModContainer::getMetadata)
+                .map(ModMetadata::getVersion).map(Version::getFriendlyString).orElse("UNKNOWN");
+    }
+
+    @Override
+    public FutureTaskId runAsync(Runnable runnable) {
+        return new FutureTaskId(CompletableFuture
+                .runAsync(runnable, ViaFabric.ASYNC_EXECUTOR)
+                .exceptionally(throwable -> {
+                    if (!(throwable instanceof CancellationException)) {
+                        throwable.printStackTrace();
+                    }
+                    return null;
+                })
+        );
+    }
+
+    @Override
+    public FutureTaskId runSync(Runnable runnable) {
+        if (getServer() != null) {
+            return runServerSync(runnable);
+        } else {
+            return runEventLoop(runnable);
+        }
+    }
+
+    private FutureTaskId runServerSync(Runnable runnable) {
+        // Kick task needs to be on main thread, it does already have error logger
+        return new FutureTaskId(CompletableFuture.runAsync(runnable, getServer()));
+    }
+
+    private FutureTaskId runEventLoop(Runnable runnable) {
+        return new FutureTaskId(
+                ViaFabric.EVENT_LOOP
+                        .submit(runnable)
+                        .addListener(errorLogger())
+        );
+    }
+
+    @Override
+    public PlatformTask runSync(Runnable runnable, Long ticks) {
+        // ViaVersion seems to not need to run delayed tasks on main thread
+        return new FutureTaskId(
+                ViaFabric.EVENT_LOOP
+                        .schedule(() -> runSync(runnable), ticks * 50, TimeUnit.MILLISECONDS)
+                        .addListener(errorLogger())
+        );
+    }
+
+    @Override
+    public PlatformTask runRepeatingSync(Runnable runnable, Long ticks) {
+        // ViaVersion seems to not need to run repeating tasks on main thread
+        return new FutureTaskId(
+                ViaFabric.EVENT_LOOP
+                        .scheduleAtFixedRate(() -> runSync(runnable), 0, ticks * 50, TimeUnit.MILLISECONDS)
+                        .addListener(errorLogger())
+        );
+    }
+
+    private <T extends Future<?>> GenericFutureListener<T> errorLogger() {
+        return future -> {
+            if (!future.isCancelled() && future.cause() != null) {
+                future.cause().printStackTrace();
+            }
+        };
+    }
+
+    @Override
+    public ViaCommandSender[] getOnlinePlayers() {
+        MinecraftServer server = getServer();
+        if (server != null && server.isOnThread()) {
+            return getServerPlayers();
+        }
+        return Via.getManager().getConnectionManager().getConnectedClients().values().stream()
+                .map(UserCommandSender::new)
+                .toArray(ViaCommandSender[]::new);
+    }
+
+    private ViaCommandSender[] getServerPlayers() {
+        return getServer().getPlayerManager().getPlayerList().stream()
+                .map(Entity::getCommandSource)
+                .map(NMSCommandSender::new)
+                .toArray(ViaCommandSender[]::new);
+    }
+
+    @Override
+    public void sendMessage(UUID uuid, String s) {
+        sendMessageServer(uuid, s);
+    }
+
+    private void sendMessageServer(UUID uuid, String s) {
+        MinecraftServer server = getServer();
+        if (server == null) return;
+        runServerSync(() -> {
+            ServerPlayerEntity player = server.getPlayerManager().getPlayer(uuid);
+            if (player == null) return;
+            player.sendMessage(Text.Serializer.fromJson(
+                    legacyToJson(s)
+            ), false);
+        });
+    }
+
+    @Override
+    public boolean kickPlayer(UUID uuid, String s) {
+        return kickServer(uuid, s);
+    }
+
+    private boolean kickServer(UUID uuid, String s) {
+        MinecraftServer server = getServer();
+        if (server == null) return false;
+        Supplier<Boolean> kickTask = () -> {
+            ServerPlayerEntity player = server.getPlayerManager().getPlayer(uuid);
+            if (player == null) return false;
+            player.networkHandler.disconnect(Text.Serializer.fromJson(legacyToJson(s)));
+            return true;
+        };
+        if (server.isOnThread()) {
+            return kickTask.get();
+        } else {
+            ViaFabric.JLOGGER.log(Level.WARNING, "Weird!? Player kicking was called off-thread", new Throwable());
+            runServerSync(kickTask::get);
+        }
+        return false;  // Can't know if it worked
+    }
+
+    @Override
+    public boolean isPluginEnabled() {
+        return true;
+    }
+
+    @Override
+    public ViaAPI<UUID> getApi() {
+        return api;
+    }
+
+    @Override
+    public ViaVersionConfig getConf() {
+        return config;
+    }
+
+    @Override
+    public ConfigurationProvider getConfigurationProvider() {
+        return config;
+    }
+
+    @Override
+    public File getDataFolder() {
+        return dataFolder;
+    }
+
+    @Override
+    public void onReload() {
+        // Nothing to do
+    }
+
+    @Override
+    public JsonObject getDump() {
+        JsonObject platformSpecific = new JsonObject();
+        List<PluginInfo> mods = new ArrayList<>();
+        for (ModContainer mod : FabricLoader.getInstance().getAllMods()) {
+            mods.add(new PluginInfo(true,
+                    mod.getMetadata().getId() + " (" + mod.getMetadata().getName() + ")",
+                    mod.getMetadata().getVersion().getFriendlyString(),
+                    null,
+                    mod.getMetadata().getAuthors().stream()
+                            .map(info -> info.getName()
+                                    + (info.getContact().asMap().isEmpty() ? "" : " " + info.getContact().asMap()))
+                            .collect(Collectors.toList())
+            ));
+        }
+
+        platformSpecific.add("mods", GsonUtil.getGson().toJsonTree(mods));
+        return platformSpecific;
+    }
+
+    @Override
+    public boolean isOldClientsAllowed() {
+        return true;
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/platform/VRViaAPI.java

@@ -0,0 +1,8 @@
+package com.viaversion.fabric.mc116.platform;
+
+import com.viaversion.viaversion.ViaAPIBase;
+
+import java.util.UUID;
+
+public class VRViaAPI extends ViaAPIBase<UUID> {
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/platform/VRViaConfig.java

@@ -0,0 +1,68 @@
+package com.viaversion.fabric.mc116.platform;
+
+import com.viaversion.viaversion.configuration.AbstractViaConfig;
+
+import java.io.File;
+import java.net.URL;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+
+public class VRViaConfig extends AbstractViaConfig {
+    // Based on Sponge ViaVersion
+    private static List<String> UNSUPPORTED = Arrays.asList("anti-xray-patch", "bungee-ping-interval",
+            "bungee-ping-save", "bungee-servers", "quick-move-action-fix", "nms-player-ticking",
+            "velocity-ping-interval", "velocity-ping-save", "velocity-servers",
+            "blockconnection-method", "change-1_9-hitbox", "change-1_14-hitbox");
+
+    public VRViaConfig(File configFile) {
+        super(configFile);
+        // Load config
+        reloadConfig();
+    }
+
+    @Override
+    public URL getDefaultConfigURL() {
+        return getClass().getClassLoader().getResource("assets/viaversion/config.yml");
+    }
+
+    @Override
+    protected void handleConfig(Map<String, Object> config) {
+        // Nothing Currently
+    }
+
+    @Override
+    public List<String> getUnsupportedOptions() {
+        return UNSUPPORTED;
+    }
+
+    @Override
+    public boolean isAntiXRay() {
+        return false;
+    }
+
+    @Override
+    public boolean isNMSPlayerTicking() {
+        return false;
+    }
+
+    @Override
+    public boolean is1_12QuickMoveActionFix() {
+        return false;
+    }
+
+    @Override
+    public String getBlockConnectionMethod() {
+        return "packet";
+    }
+
+    @Override
+    public boolean is1_9HitboxFix() {
+        return false;
+    }
+
+    @Override
+    public boolean is1_14HitboxFix() {
+        return false;
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/protocol/ViaFabricHostnameProtocol.java

@@ -0,0 +1,34 @@
+package com.viaversion.fabric.mc116.protocol;
+
+import com.viaversion.fabric.mc116.ViaFabricAddress;
+import com.viaversion.viaversion.api.protocol.AbstractSimpleProtocol;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.protocol.remapper.PacketRemapper;
+import com.viaversion.viaversion.api.protocol.remapper.ValueTransformer;
+import com.viaversion.viaversion.api.type.Type;
+import com.viaversion.viaversion.api.protocol.packet.State;
+
+public class ViaFabricHostnameProtocol extends AbstractSimpleProtocol {
+    public static final ViaFabricHostnameProtocol INSTANCE = new ViaFabricHostnameProtocol();
+
+    @Override
+    protected void registerPackets() {
+        registerServerbound(State.HANDSHAKE, 0, 0, new PacketRemapper() {
+            @Override
+            public void registerMap() {
+                map(Type.VAR_INT); // Protocol version
+                map(Type.STRING, new ValueTransformer<String, String>(Type.STRING) {
+                    @Override
+                    public String transform(PacketWrapper packetWrapper, String s) {
+                        return new ViaFabricAddress().parse(s).realAddress;
+                    }
+                });
+            }
+        });
+    }
+
+    @Override
+    public boolean isBaseProtocol() {
+        return true;
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/providers/VRHandItemProvider.java

@@ -0,0 +1,110 @@
+package com.viaversion.fabric.mc116.providers;
+
+import com.viaversion.fabric.mc116.ViaFabric;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.api.Environment;
+import net.fabricmc.fabric.api.client.event.lifecycle.v1.ClientTickEvents;
+import net.fabricmc.fabric.api.event.lifecycle.v1.ServerTickEvents;
+import net.fabricmc.fabric.api.event.world.WorldTickCallback;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.network.ClientPlayerEntity;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.registry.Registry;
+import net.minecraft.util.Identifier;
+import net.minecraft.world.World;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.minecraft.item.Item;
+import com.viaversion.viaversion.protocols.protocol1_9to1_8.providers.HandItemProvider;
+
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+
+public class VRHandItemProvider extends HandItemProvider {
+    public Item clientItem = null;
+    public Map<UUID, Item> serverPlayers = new ConcurrentHashMap<>();
+
+    @Override
+    public Item getHandItem(UserConnection info) {
+        Item serverItem;
+        if (info.isClientSide()) {
+            return getClientItem();
+        } else if ((serverItem = serverPlayers.get(info.getProtocolInfo().getUuid())) != null) {
+            return new Item(serverItem);
+        }
+        return super.getHandItem(info);
+    }
+
+    private Item getClientItem() {
+        if (clientItem == null) {
+            return new Item(0, (byte) 0, (short) 0, null);
+        }
+        return new Item(clientItem);
+    }
+
+    @Environment(EnvType.CLIENT)
+    public void registerClientTick() {
+        try {
+            ClientTickEvents.END_WORLD_TICK.register(clientWorld -> tickClient());
+        } catch (NoClassDefFoundError ignored) {
+            try {
+                WorldTickCallback.EVENT.register(world -> {
+                    if (world.isClient) {
+                        tickClient();
+                    }
+                });
+            } catch (NoClassDefFoundError ignored2) {
+                ViaFabric.JLOGGER.info("Fabric Lifecycle V0/V1 isn't installed");
+            }
+        }
+    }
+
+    public void registerServerTick() {
+        try {
+            ServerTickEvents.END_WORLD_TICK.register(this::tickServer);
+        } catch (NoClassDefFoundError ignored) {
+            WorldTickCallback.EVENT.register(world -> {
+                if (!world.isClient) {
+                    tickServer(world);
+                }
+            });
+        }
+    }
+
+    private void tickClient() {
+        ClientPlayerEntity p = MinecraftClient.getInstance().player;
+        if (p != null) {
+            clientItem = fromNative(p.inventory.getMainHandStack());
+        }
+    }
+
+    private void tickServer(World world) {
+        serverPlayers.clear();
+        world.getPlayers().forEach(it -> serverPlayers
+                .put(it.getUuid(), fromNative(it.inventory.getMainHandStack())));
+    }
+
+    private Item fromNative(ItemStack original) {
+        Identifier iid = Registry.ITEM.getId(original.getItem());
+        if (iid == null) return new Item(0, (byte) 0, (short) 0, null);
+        int id = swordId(iid.toString());
+        return new Item(id, (byte) original.getCount(), (short) original.getDamage(), null);
+    }
+
+    private int swordId(String id) {
+        // https://github.com/ViaVersion/ViaVersion/blob/8de26a0ad33f5b739f5394ed80f69d14197fddc7/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_9to1_8/Protocol1_9To1_8.java#L86
+        switch (id) {
+            case "minecraft:iron_sword":
+                return 267;
+            case "minecraft:wooden_sword":
+                return 268;
+            case "minecraft:golden_sword":
+                return 272;
+            case "minecraft:diamond_sword":
+                return 276;
+            case "minecraft:stone_sword":
+                return 283;
+        }
+        return 0;
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/providers/VRVersionProvider.java

@@ -0,0 +1,166 @@
+package com.viaversion.fabric.mc116.providers;
+
+import com.viaversion.fabric.mc116.ViaFabric;
+import com.viaversion.fabric.mc116.ViaFabricAddress;
+import com.viaversion.fabric.mc116.service.ProtocolAutoDetector;
+import com.viaversion.fabric.mc116.util.ProtocolUtils;
+import com.google.common.primitives.Ints;
+import com.viaversion.viaversion.api.connection.ProtocolInfo;
+import net.fabricmc.loader.api.FabricLoader;
+import net.minecraft.network.ClientConnection;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+import com.viaversion.viaversion.api.type.Type;
+import com.viaversion.viaversion.exception.CancelException;
+import com.viaversion.viaversion.api.protocol.packet.State;
+import com.viaversion.viaversion.protocols.base.*;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.net.InetSocketAddress;
+import java.net.SocketAddress;
+import java.util.*;
+import java.util.stream.IntStream;
+
+public class VRVersionProvider extends BaseVersionProvider {
+    private int[] multiconnectSupportedVersions = null;
+
+    {
+        try {
+            if (FabricLoader.getInstance().isModLoaded("multiconnect")) {
+                Class<?> mcApiClass = Class.forName("net.earthcomputer.multiconnect.api.MultiConnectAPI");
+                Class<?> iProtocolClass = Class.forName("net.earthcomputer.multiconnect.api.IProtocol");
+                Object mcApiInstance = mcApiClass.getMethod("instance").invoke(null);
+                List<?> protocols = (List<?>) mcApiClass.getMethod("getSupportedProtocols").invoke(mcApiInstance);
+                Method getValue = iProtocolClass.getMethod("getValue");
+                Method isMulticonnectBeta;
+                try {
+                    isMulticonnectBeta = iProtocolClass.getMethod("isMulticonnectBeta");
+                } catch (NoSuchMethodException e) {
+                    isMulticonnectBeta = null;
+                }
+                Set<Integer> vers = new TreeSet<>();
+                for (Object protocol : protocols) {
+                    // Do not use versions with beta multiconnect support, which may have stability issues
+                    if (isMulticonnectBeta == null || !(Boolean) isMulticonnectBeta.invoke(protocol)) {
+                        vers.add((Integer) getValue.invoke(protocol));
+                    }
+                }
+                multiconnectSupportedVersions = vers.stream().mapToInt(Integer::intValue).toArray();
+                ViaFabric.JLOGGER.info("ViaFabric will integrate with multiconnect");
+            }
+        } catch (ClassNotFoundException | IllegalAccessException | InvocationTargetException | NoSuchMethodException
+                | ClassCastException ignored) {
+        }
+    }
+
+    @Override
+    public int getClosestServerProtocol(UserConnection connection) throws Exception {
+        if (connection.isClientSide()) {
+            ProtocolInfo info = Objects.requireNonNull(connection.getProtocolInfo());
+
+            if (!ViaFabric.config.isClientSideEnabled()) {
+                return info.getProtocolVersion();
+            }
+
+            int serverVer = ViaFabric.config.getClientSideVersion();
+            SocketAddress addr = connection.getChannel().remoteAddress();
+
+            if (addr instanceof InetSocketAddress) {
+                int addrVersion = new ViaFabricAddress().parse(((InetSocketAddress) addr).getHostName()).protocol;
+                if (addrVersion != 0) serverVer = addrVersion;
+
+                try {
+                    if (serverVer == -2) {
+                        // Hope protocol was autodetected
+                        ProtocolVersion autoVer =
+                                ProtocolAutoDetector.detectVersion((InetSocketAddress) addr).getNow(null);
+                        if (autoVer != null) {
+                            serverVer = autoVer.getVersion();
+                        }
+                    }
+                } catch (Exception e) {
+                    ViaFabric.JLOGGER.warning("Couldn't auto detect: " + e);
+                }
+            }
+
+            boolean blocked = checkAddressBlocked(addr);
+            boolean supported = ProtocolUtils.isSupported(serverVer, info.getProtocolVersion());
+
+            handleMulticonnectPing(connection, info, blocked, serverVer);
+
+            if (blocked || !supported) serverVer = info.getProtocolVersion();
+
+            return serverVer;
+        }
+        return super.getClosestServerProtocol(connection);
+    }
+
+    private boolean checkAddressBlocked(SocketAddress addr) {
+        return addr instanceof InetSocketAddress && (isDisabled(((InetSocketAddress) addr).getHostString())
+                || ((((InetSocketAddress) addr).getAddress() != null) &&
+                (isDisabled(((InetSocketAddress) addr).getAddress().getHostAddress())
+                        || isDisabled(((InetSocketAddress) addr).getAddress().getHostName()))));
+    }
+
+    private void handleMulticonnectPing(UserConnection connection, ProtocolInfo info, boolean blocked, int serverVer) throws Exception {
+        if (info.getState() == State.STATUS
+                && info.getProtocolVersion() == -1
+                && connection.getChannel().pipeline().get(ClientConnection.class).getPacketListener()
+                .getClass().getName().startsWith("net.earthcomputer.multiconnect")
+                && (blocked || ProtocolUtils.isSupported(serverVer, getVersionForMulticonnect(serverVer)))) { // Intercept the connection
+            int multiconnectSuggestion = blocked ? -1 : getVersionForMulticonnect(serverVer);
+            ViaFabric.JLOGGER.info("Sending " + ProtocolVersion.getProtocol(multiconnectSuggestion) + " for multiconnect version detector");
+            PacketWrapper newAnswer = PacketWrapper.create(0x00, null, connection);
+            newAnswer.write(Type.STRING, "{\"version\":{\"name\":\"viafabric integration\",\"protocol\":" + multiconnectSuggestion + "}}");
+            newAnswer.send(info.getPipeline().contains(BaseProtocol1_16.class) ? BaseProtocol1_16.class : BaseProtocol1_7.class, true, true);
+            throw CancelException.generate();
+        }
+    }
+
+    private int getVersionForMulticonnect(int clientSideVersion) {
+        // https://github.com/ViaVersion/ViaVersion/blob/master/velocity/src/main/java/us/myles/ViaVersion/velocity/providers/VelocityVersionProvider.java
+        int[] compatibleProtocols = multiconnectSupportedVersions;
+
+        if (Arrays.binarySearch(compatibleProtocols, clientSideVersion) >= 0) {
+            return clientSideVersion;
+        }
+
+        if (clientSideVersion < compatibleProtocols[0]) {
+            return compatibleProtocols[0];
+        }
+
+        // TODO: This needs a better fix, i.e checking ProtocolRegistry to see if it would work.
+        for (int i = compatibleProtocols.length - 1; i >= 0; i--) {
+            int protocol = compatibleProtocols[i];
+            if (clientSideVersion > protocol && ProtocolVersion.isRegistered(protocol)) {
+                return protocol;
+            }
+        }
+
+        ViaFabric.JLOGGER.severe("multiconnect integration: Panic, no protocol id found for " + clientSideVersion);
+        return clientSideVersion;
+    }
+
+    private boolean isDisabled(String addr) {
+        String[] parts = addr.split("\\.");
+        boolean isNumericIp = parts.length == 4 && Arrays.stream(parts).map(Ints::tryParse).allMatch(Objects::nonNull);
+        return IntStream.range(0, parts.length).anyMatch(i -> {
+            String query;
+            if (isNumericIp) {
+                query = String.join(".", Arrays.stream(parts, 0, i + 1)
+                        .toArray(String[]::new)) + ((i != 3) ? ".*" : "");
+            } else {
+                query = ((i != 0) ? "*." : "") + String.join(".", Arrays.stream(parts, i, parts.length)
+                        .toArray(String[]::new));
+            }
+            if (ViaFabric.config.isForcedDisable(query)) {
+                ViaFabric.JLOGGER.info(addr + " is force-disabled. (Matches " + query + ")");
+                return true;
+            } else {
+                return false;
+            }
+        });
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/service/ProtocolAutoDetector.java

@@ -0,0 +1,125 @@
+package com.viaversion.fabric.mc116.service;
+
+import com.viaversion.fabric.mc116.ViaFabric;
+import com.viaversion.fabric.mc116.ViaFabricAddress;
+import com.google.common.cache.CacheBuilder;
+import com.google.common.cache.CacheLoader;
+import com.google.common.cache.LoadingCache;
+import io.netty.bootstrap.Bootstrap;
+import io.netty.channel.*;
+import io.netty.channel.socket.nio.NioSocketChannel;
+import io.netty.handler.timeout.ReadTimeoutHandler;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.api.Environment;
+import net.minecraft.network.*;
+import net.minecraft.network.listener.ClientQueryPacketListener;
+import net.minecraft.network.packet.c2s.handshake.HandshakeC2SPacket;
+import net.minecraft.network.packet.c2s.query.QueryRequestC2SPacket;
+import net.minecraft.network.packet.s2c.query.QueryPongS2CPacket;
+import net.minecraft.network.packet.s2c.query.QueryResponseS2CPacket;
+import net.minecraft.server.ServerMetadata;
+import net.minecraft.text.LiteralText;
+import net.minecraft.text.Text;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.UnknownHostException;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+import java.util.logging.Level;
+
+@Environment(EnvType.CLIENT)
+public class ProtocolAutoDetector {
+    private static LoadingCache<InetSocketAddress, CompletableFuture<ProtocolVersion>> SERVER_VER = CacheBuilder.newBuilder()
+            .expireAfterAccess(100, TimeUnit.SECONDS)
+            .build(CacheLoader.from((address) -> {
+                CompletableFuture<ProtocolVersion> future = new CompletableFuture<>();
+
+                try {
+                    final ClientConnection clientConnection = new ClientConnection(NetworkSide.CLIENTBOUND);
+
+                    ChannelFuture ch = new Bootstrap()
+                            .group(ClientConnection.CLIENT_IO_GROUP.get())
+                            .channel(NioSocketChannel.class)
+                            .handler(new ChannelInitializer<Channel>() {
+                                protected void initChannel(Channel channel) {
+                                    try {
+                                        channel.config().setOption(ChannelOption.TCP_NODELAY, true);
+                                        channel.config().setOption(ChannelOption.IP_TOS, 0x18); // Stolen from Velocity, low delay, high reliability
+                                    } catch (ChannelException ignored) {
+                                    }
+
+                                    channel.pipeline()
+                                            .addLast("timeout", new ReadTimeoutHandler(30))
+                                            .addLast("splitter", new SplitterHandler())
+                                            .addLast("decoder", new DecoderHandler(NetworkSide.CLIENTBOUND))
+                                            .addLast("prepender", new SizePrepender())
+                                            .addLast("encoder", new PacketEncoder(NetworkSide.SERVERBOUND))
+                                            .addLast("packet_handler", clientConnection);
+                                }
+                            })
+                            .connect(address);
+
+                    ch.addListener(future1 -> {
+                        if (!future1.isSuccess()) {
+                            future.completeExceptionally(future1.cause());
+                        } else {
+                            ch.channel().eventLoop().execute(() -> { // needs to execute after channel init
+                                clientConnection.setPacketListener(new ClientQueryPacketListener() {
+                                    @Override
+                                    public void onResponse(QueryResponseS2CPacket packet) {
+                                        ServerMetadata meta = packet.getServerMetadata();
+                                        ServerMetadata.Version version;
+                                        if (meta != null && (version = meta.getVersion()) != null) {
+                                            ProtocolVersion ver = ProtocolVersion.getProtocol(version.getProtocolVersion());
+                                            future.complete(ver);
+                                            ViaFabric.JLOGGER.info("Auto-detected " + ver + " for " + address);
+                                        } else {
+                                            future.completeExceptionally(new IllegalArgumentException("Null version in query response"));
+                                        }
+                                        clientConnection.disconnect(LiteralText.EMPTY);
+                                    }
+
+                                    @Override
+                                    public void onPong(QueryPongS2CPacket packet) {
+                                        clientConnection.disconnect(new LiteralText("Pong not requested!"));
+                                    }
+
+                                    @Override
+                                    public void onDisconnected(Text reason) {
+                                        future.completeExceptionally(new IllegalStateException(reason.asString()));
+                                    }
+
+                                    @Override
+                                    public ClientConnection getConnection() {
+                                        return clientConnection;
+                                    }
+                                });
+
+                                clientConnection.send(new HandshakeC2SPacket(address.getHostString(),
+                                        address.getPort(), NetworkState.STATUS));
+                                clientConnection.send(new QueryRequestC2SPacket());
+                            });
+                        }
+                    });
+                } catch (Throwable throwable) {
+                    future.completeExceptionally(throwable);
+                }
+
+                return future;
+            }));
+
+    public static CompletableFuture<ProtocolVersion> detectVersion(InetSocketAddress address) {
+        try {
+            InetSocketAddress real = new InetSocketAddress(InetAddress.getByAddress
+                    (new ViaFabricAddress().parse(address.getHostString()).realAddress,
+                            address.getAddress().getAddress()), address.getPort());
+            return SERVER_VER.get(real);
+        } catch (UnknownHostException | ExecutionException e) {
+            ViaFabric.JLOGGER.log(Level.WARNING, "Protocol auto detector error: ", e);
+            return CompletableFuture.completedFuture(null);
+        }
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/util/FutureTaskId.java

@@ -0,0 +1,23 @@
+package com.viaversion.fabric.mc116.util;
+
+import com.viaversion.viaversion.api.platform.PlatformTask;
+
+import java.util.concurrent.Future;
+
+public class FutureTaskId implements PlatformTask<Future<?>> {
+    private final Future<?> object;
+
+    public FutureTaskId(Future<?> object) {
+        this.object = object;
+    }
+
+    @Override
+    public Future<?> getObject() {
+        return object;
+    }
+
+    @Override
+    public void cancel() {
+        object.cancel(false);
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/util/JLoggerToLog4j.java

@@ -0,0 +1,68 @@
+package com.viaversion.fabric.mc116.util;
+
+import java.text.MessageFormat;
+import java.util.logging.Level;
+import java.util.logging.LogRecord;
+import java.util.logging.Logger;
+
+public class JLoggerToLog4j extends Logger {
+    private final org.apache.logging.log4j.Logger base;
+
+    public JLoggerToLog4j(org.apache.logging.log4j.Logger logger) {
+        super("logger", null);
+        this.base = logger;
+    }
+
+    public void log(LogRecord record) {
+        this.log(record.getLevel(), record.getMessage());
+    }
+
+    public void log(Level level, String msg) {
+        if (level == Level.FINE) {
+            this.base.debug(msg);
+        } else if (level == Level.WARNING) {
+            this.base.warn(msg);
+        } else if (level == Level.SEVERE) {
+            this.base.error(msg);
+        } else if (level == Level.INFO) {
+            this.base.info(msg);
+        } else {
+            this.base.trace(msg);
+        }
+
+    }
+
+    public void log(Level level, String msg, Object param1) {
+        if (level == Level.FINE) {
+            this.base.debug(msg, param1);
+        } else if (level == Level.WARNING) {
+            this.base.warn(msg, param1);
+        } else if (level == Level.SEVERE) {
+            this.base.error(msg, param1);
+        } else if (level == Level.INFO) {
+            this.base.info(msg, param1);
+        } else {
+            this.base.trace(msg, param1);
+        }
+
+    }
+
+    public void log(Level level, String msg, Object[] params) {
+        log(level, MessageFormat.format(msg, params));
+    }
+
+    public void log(Level level, String msg, Throwable params) {
+        if (level == Level.FINE) {
+            this.base.debug(msg, params);
+        } else if (level == Level.WARNING) {
+            this.base.warn(msg, params);
+        } else if (level == Level.SEVERE) {
+            this.base.error(msg, params);
+        } else if (level == Level.INFO) {
+            this.base.info(msg, params);
+        } else {
+            this.base.trace(msg, params);
+        }
+
+    }
+}

viafabric-mc116/src/main/java/com/viaversion/fabric/mc116/util/ProtocolUtils.java

@@ -0,0 +1,60 @@
+package com.viaversion.fabric.mc116.util;
+
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+
+import java.util.Arrays;
+import java.util.stream.Stream;
+
+public class ProtocolUtils {
+    public static boolean isSupported(int server, int client) {
+        return server == client || Via.getManager().getProtocolManager().getProtocolPath(client, server) != null;
+    }
+
+    public static String getProtocolName(int id) {
+        if (!ProtocolVersion.isRegistered(id)) return Integer.toString(id);
+        return ProtocolVersion.getProtocol(id).getName();
+    }
+
+    public static boolean isStartOfProtocolText(String s) {
+        try {
+            Integer.parseInt(s);
+            return true;
+        } catch (NumberFormatException e) {
+            try {
+                Integer.parseInt(s + '0');
+                return true;
+            } catch (NumberFormatException e2) {
+                return ProtocolVersion.getProtocols().stream()
+                        .map(ProtocolVersion::getName)
+                        .flatMap(str -> Stream.concat(
+                                Arrays.stream(str.split("-")),
+                                Arrays.stream(new String[]{str})
+                        ))
+                        .anyMatch(ver -> ver.startsWith(s));
+            }
+        }
+    }
+
+    public static Integer parseProtocolId(String s) {
+        try {
+            return Integer.parseInt(s);
+        } catch (NumberFormatException ignored) {
+            ProtocolVersion closest = ProtocolVersion.getClosest(s);
+            if (closest == null) return null;
+            return closest.getVersion();
+        }
+    }
+
+    public static String[] getProtocolSuggestions(String text) {
+        return ProtocolVersion.getProtocols().stream()
+                .map(ProtocolVersion::getName)
+                .flatMap(str -> Stream.concat(
+                        Arrays.stream(str.split("-")),
+                        Arrays.stream(new String[]{str})
+                ))
+                .distinct()
+                .filter(ver -> ver.startsWith(text))
+                .toArray(String[]::new);
+    }
+}

viafabric-mc116/src/main/resources/fabric.mod.json

@@ -0,0 +1,57 @@
+{
+  "schemaVersion": 1,
+  "id": "viafabric-mc116",
+  "name": "ViaFabric",
+  "version": "@version@",
+  "description": "@description@",
+  "license": "GPL-3.0",
+  "contact": {
+    "homepage": "https://viaversion.com/fabric",
+    "issues": "https://github.com/ViaVersion/ViaFabric/issues",
+    "sources": "https://github.com/ViaVersion/ViaFabric"
+  },
+  "environment": "*",
+  "authors": [
+    {
+      "name": "creeper123123321",
+      "contact": {
+        "homepage": "https://creeper123123321.github.io/"
+      }
+    }
+  ],
+  "contributors": [
+    {
+      "name": "GitHub contributors",
+      "contact": {
+        "homepage": "https://github.com/ViaVersion/ViaFabric/graphs/contributors"
+      }
+    }
+  ],
+  "entrypoints": {
+    "main": [
+      "com.viaversion.fabric.mc116.ViaFabric"
+    ],
+    "modmenu": [
+      "com.viaversion.fabric.mc116.gui.ModMenuConfig"
+    ]
+  },
+  "depends": {
+    "fabricloader": ">=0.4.0",
+    "fabric-resource-loader-v0": "*",
+    "minecraft": "1.16.x",
+    "viaversion": ">3.0.1"
+  },
+  "conflicts": {
+    "fabric-registry-sync-v0": "*"
+  },
+  "recommends": {
+    "fabric-command-api-v1": "*"
+  },
+  "icon": "assets/viafabric/textures/logo.png",
+  "mixins": [
+    "mixins.viafabric.address.json",
+    "mixins.viafabric.gui.json",
+    "mixins.viafabric.debug.json",
+    "mixins.viafabric.pipeline.json"
+  ]
+}

viafabric-mc116/src/main/resources/mixins.viafabric.address.json

@@ -0,0 +1,14 @@
+{
+  "required": true,
+  "compatibilityLevel": "JAVA_8",
+  "mixins": [
+  ],
+  "client": [
+    "com.viaversion.fabric.mc116.mixin.address.client.MixinConnectScreenThread",
+    "com.viaversion.fabric.mc116.mixin.address.client.MixinServerAddress",
+    "com.viaversion.fabric.mc116.mixin.address.client.MixinServerPinger"
+  ],
+  "injectors": {
+    "defaultRequire": 1
+  }
+}

viafabric-mc116/src/main/resources/mixins.viafabric.debug.json

@@ -0,0 +1,13 @@
+{
+  "required": true,
+  "compatibilityLevel": "JAVA_8",
+  "mixins": [
+  ],
+  "client": [
+    "com.viaversion.fabric.mc116.mixin.debug.client.MixinClientConnectionAccessor",
+    "com.viaversion.fabric.mc116.mixin.debug.client.MixinDebugHud"
+  ],
+  "injectors": {
+    "defaultRequire": 0
+  }
+}

viafabric-mc116/src/main/resources/mixins.viafabric.gui.json

@@ -0,0 +1,12 @@
+{
+  "required": true,
+  "compatibilityLevel": "JAVA_8",
+  "mixins": [
+  ],
+  "client": [
+    "com.viaversion.fabric.mc116.mixin.gui.client.MixinMultiplayerScreen"
+  ],
+  "injectors": {
+    "defaultRequire": 0
+  }
+}

viafabric-mc116/src/main/resources/mixins.viafabric.pipeline.json

@@ -0,0 +1,14 @@
+{
+  "required": true,
+  "compatibilityLevel": "JAVA_8",
+  "mixins": [
+    "com.viaversion.fabric.mc116.mixin.pipeline.MixinClientConnection",
+    "com.viaversion.fabric.mc116.mixin.pipeline.MixinServerNetworkIoChInit"
+  ],
+  "client": [
+    "com.viaversion.fabric.mc116.mixin.pipeline.client.MixinClientConnectionChInit"
+  ],
+  "injectors": {
+    "defaultRequire": 1
+  }
+}

viafabric-mc117/src/main/resources/fabric.mod.json

@@ -1,6 +1,6 @@
 {
   "schemaVersion": 1,
-  "id": "viafabric-impl",
+  "id": "viafabric-mc117",
   "name": "ViaFabric",
   "version": "@version@",
   "description": "@description@",
@@ -8,8 +8,7 @@
   "contact": {
     "homepage": "https://viaversion.com/fabric",
     "issues": "https://github.com/ViaVersion/ViaFabric/issues",
-    "sources": "https://github.com/ViaVersion/ViaFabric",
+    "sources": "https://github.com/ViaVersion/ViaFabric"
-    "discord": "https://discord.gg/viaversion"
   },
   "environment": "*",
   "authors": [

viafabric-mc117/src/main/resources/mixins.viafabric.address.json

@@ -1,13 +1,12 @@
 {
   "required": true,
   "compatibilityLevel": "JAVA_8",
-  "package": "com.viaversion.fabric.mc117.mixin.address",
   "mixins": [
   ],
   "client": [
-    "client.MixinConnectScreenThread",
+    "com.viaversion.fabric.mc117.mixin.address.client.MixinConnectScreenThread",
-    "client.MixinServerAddress",
+    "com.viaversion.fabric.mc117.mixin.address.client.MixinServerAddress",
-    "client.MixinServerPinger"
+    "com.viaversion.fabric.mc117.mixin.address.client.MixinServerPinger"
   ],
   "injectors": {
     "defaultRequire": 1

viafabric-mc117/src/main/resources/mixins.viafabric.debug.json

@@ -1,12 +1,11 @@
 {
   "required": true,
   "compatibilityLevel": "JAVA_8",
-  "package": "com.viaversion.fabric.mc117.mixin.debug",
   "mixins": [
   ],
   "client": [
-    "client.MixinClientConnectionAccessor",
+    "com.viaversion.fabric.mc117.mixin.debug.client.MixinClientConnectionAccessor",
-    "client.MixinDebugHud"
+    "com.viaversion.fabric.mc117.mixin.debug.client.MixinDebugHud"
   ],
   "injectors": {
     "defaultRequire": 0

viafabric-mc117/src/main/resources/mixins.viafabric.gui.json

@@ -1,11 +1,10 @@
 {
   "required": true,
   "compatibilityLevel": "JAVA_8",
-  "package": "com.viaversion.fabric.mc117.mixin.gui",
   "mixins": [
   ],
   "client": [
-    "client.MixinMultiplayerScreen"
+    "com.viaversion.fabric.mc117.mixin.gui.client.MixinMultiplayerScreen"
   ],
   "injectors": {
     "defaultRequire": 0

viafabric-mc117/src/main/resources/mixins.viafabric.pipeline.json

@@ -1,13 +1,12 @@
 {
   "required": true,
   "compatibilityLevel": "JAVA_8",
-  "package": "com.viaversion.fabric.mc117.mixin.pipeline",
   "mixins": [
-    "MixinClientConnection",
+    "com.viaversion.fabric.mc117.mixin.pipeline.MixinClientConnection",
-    "MixinServerNetworkIoChInit"
+    "com.viaversion.fabric.mc117.mixin.pipeline.MixinServerNetworkIoChInit"
   ],
   "client": [
-    "client.MixinClientConnectionChInit"
+    "com.viaversion.fabric.mc117.mixin.pipeline.client.MixinClientConnectionChInit"
   ],
   "injectors": {
     "defaultRequire": 1

viafabric-mc18/build.gradle.kts

@@ -1,3 +1,4 @@
+import java.util.function.Function as JFun
 version = rootProject.version
 
 dependencies {
@@ -8,3 +9,9 @@ dependencies {
 	modImplementation("net.legacyfabric.legacy-fabric-api:legacy-fabric-api:1.1.0+1.8.9")
 	modImplementation("io.github.boogiemonster1o1:modmenu:0.1.0+1.8.9")
 }
+
+minecraft {
+	intermediaryUrl = JFun {
+		"https://maven.legacyfabric.net/net/fabricmc/intermediary/$it/intermediary-$it-v2.jar"
+	}
+}

viafabric-mc18/src/main/resources/fabric.mod.json

@@ -1,6 +1,6 @@
 {
   "schemaVersion": 1,
-  "id": "viafabric-impl",
+  "id": "viafabric-mc18",
   "name": "ViaFabric",
   "version": "@version@",
   "description": "@description@",

viafabric-mc18/src/main/resources/mixins.viafabric.address.json

@@ -1,13 +1,12 @@
 {
   "required": true,
   "compatibilityLevel": "JAVA_8",
-  "package": "com.viaversion.fabric.mc18.mixin.address",
   "mixins": [
   ],
   "client": [
-    "client.MixinConnectScreenThread",
+    "com.viaversion.fabric.mc18.mixin.address.client.MixinConnectScreenThread",
-    "client.MixinServerAddress",
+    "com.viaversion.fabric.mc18.mixin.address.client.MixinServerAddress",
-    "client.MixinServerPinger"
+    "com.viaversion.fabric.mc18.mixin.address.client.MixinServerPinger"
   ],
   "injectors": {
     "defaultRequire": 1

viafabric-mc18/src/main/resources/mixins.viafabric.debug.json

@@ -1,12 +1,11 @@
 {
   "required": true,
   "compatibilityLevel": "JAVA_8",
-  "package": "com.viaversion.fabric.mc18.mixin.debug",
   "mixins": [
   ],
   "client": [
-    "client.MixinClientConnectionAccessor",
+    "com.viaversion.fabric.mc18.mixin.debug.client.MixinClientConnectionAccessor",
-    "client.MixinDebugHud"
+    "com.viaversion.fabric.mc18.mixin.debug.client.MixinDebugHud"
   ],
   "injectors": {
     "defaultRequire": 0

viafabric-mc18/src/main/resources/mixins.viafabric.gui.json

@@ -1,11 +1,10 @@
 {
   "required": true,
   "compatibilityLevel": "JAVA_8",
-  "package": "com.viaversion.fabric.mc18.mixin.gui",
   "mixins": [
   ],
   "client": [
-    "client.MixinMultiplayerScreen"
+    "com.viaversion.fabric.mc18.mixin.gui.client.MixinMultiplayerScreen"
   ],
   "injectors": {
     "defaultRequire": 0