Add option to kick player via plugin messaging

bans-core/src/main/java/space/arim/libertybans/core/config/MainConfig.java

@@ -153,6 +153,24 @@ interface Commands {
 
 	interface Platforms {
 
+		@SubSection
+		Bukkit bukkit();
+
+		interface Bukkit {
+
+			@ConfKey("kick-via-plugin-messaging")
+			@ConfComments({
+					"This option is relevant for backend servers running within a network (BungeeCord or Velocity).",
+					"It instructs the proxy to kick the player from the network via plugin messaging.",
+					"",
+					"If enabled, the player will NOT be kicked by the backend server, so you MUST use a proxy",
+					"otherwise players will not be kicked at all."
+			})
+			@DefaultBoolean(false)
+			boolean kickViaPluginMessaging();
+
+		}
+
 		@SubSection
 		Sponge sponge();
 

bans-env/spigot/pom.xml

@@ -1,3 +1,22 @@
+<!--
+  ~ LibertyBans
+  ~ Copyright © 2023 Anand Beh
+  ~
+  ~ LibertyBans is free software: you can redistribute it and/or modify
+  ~ it under the terms of the GNU Affero General Public License as
+  ~ published by the Free Software Foundation, either version 3 of the
+  ~ License, or (at your option) any later version.
+  ~
+  ~ LibertyBans is distributed in the hope that it will be useful,
+  ~ but WITHOUT ANY WARRANTY; without even the implied warranty of
+  ~ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+  ~ GNU Affero General Public License for more details.
+  ~
+  ~ You should have received a copy of the GNU Affero General Public License
+  ~ along with LibertyBans. If not, see <https://www.gnu.org/licenses/>
+  ~ and navigate to version 3 of the GNU Affero General Public License.
+  -->
+
 <project xmlns="http://maven.apache.org/POM/4.0.0"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
@@ -58,6 +77,10 @@
 			<groupId>space.arim.morepaperlib</groupId>
 			<artifactId>morepaperlib</artifactId>
 		</dependency>
+		<dependency>
+			<groupId>net.kyori</groupId>
+			<artifactId>adventure-text-serializer-legacy</artifactId>
+		</dependency>
 
 		<dependency>
 			<groupId>org.junit.jupiter</groupId>

bans-env/spigot/src/main/java/module-info.java

@@ -4,6 +4,7 @@
 */
 module space.arim.libertybans.env.spigot {
 	requires jakarta.inject;
+	requires net.kyori.adventure.text.serializer.legacy;
 	requires org.slf4j;
 	requires space.arim.api.env;
 	requires space.arim.api.env.bukkit;

bans-env/spigot/src/main/java/space/arim/libertybans/env/spigot/ChannelRegistration.java

@@ -0,0 +1,47 @@
+/*
+ * LibertyBans
+ * Copyright © 2023 Anand Beh
+ *
+ * LibertyBans is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * LibertyBans is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with LibertyBans. If not, see <https://www.gnu.org/licenses/>
+ * and navigate to version 3 of the GNU Affero General Public License.
+ */
+
+package space.arim.libertybans.env.spigot;
+
+import jakarta.inject.Inject;
+import org.bukkit.plugin.Plugin;
+import space.arim.libertybans.core.env.PlatformListener;
+
+public final class ChannelRegistration implements PlatformListener {
+
+	private final Plugin plugin;
+
+	static final String BUNGEE_CHANNEL = "BungeeCord";
+
+	@Inject
+	public ChannelRegistration(Plugin plugin) {
+		this.plugin = plugin;
+	}
+
+	@Override
+	public void register() {
+		plugin.getServer().getMessenger().registerOutgoingPluginChannel(plugin, BUNGEE_CHANNEL);
+	}
+
+	@Override
+	public void unregister() {
+		plugin.getServer().getMessenger().unregisterOutgoingPluginChannel(plugin, BUNGEE_CHANNEL);
+	}
+
+}

bans-env/spigot/src/main/java/space/arim/libertybans/env/spigot/SpigotEnforcer.java

@@ -1,6 +1,6 @@
 /*
  * LibertyBans
- * Copyright © 2022 Anand Beh
+ * Copyright © 2023 Anand Beh
  *
  * LibertyBans is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
@@ -22,32 +22,40 @@
 import jakarta.inject.Inject;
 import jakarta.inject.Singleton;
 import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
 import org.bukkit.Server;
 import org.bukkit.command.CommandSender;
 import org.bukkit.entity.Player;
 import space.arim.api.env.AudienceRepresenter;
+import space.arim.libertybans.core.config.Configs;
 import space.arim.libertybans.core.config.InternalFormatter;
 import space.arim.libertybans.core.env.AbstractEnvEnforcer;
 import space.arim.libertybans.core.env.Interlocutor;
 import space.arim.morepaperlib.adventure.MorePaperLibAdventure;
 import space.arim.omnibus.util.concurrent.CentralisedFuture;
 import space.arim.omnibus.util.concurrent.FactoryOfTheFuture;
 
+import java.io.ByteArrayOutputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.io.UncheckedIOException;
 import java.net.InetAddress;
 import java.util.UUID;
 import java.util.function.Consumer;
 
 @Singleton
 public class SpigotEnforcer extends AbstractEnvEnforcer<Player> {
 
+	private final Configs configs;
 	private final Server server;
 	private final MorePaperLibAdventure morePaperLibAdventure;
 
 	@Inject
 	public SpigotEnforcer(FactoryOfTheFuture futuresFactory, InternalFormatter formatter,
 						  Interlocutor interlocutor, AudienceRepresenter<CommandSender> audienceRepresenter,
-						  Server server, MorePaperLibAdventure morePaperLibAdventure) {
+						  Configs configs, Server server, MorePaperLibAdventure morePaperLibAdventure) {
 		super(futuresFactory, formatter, interlocutor, audienceRepresenter);
+		this.configs = configs;
 		this.server = server;
 		this.morePaperLibAdventure = morePaperLibAdventure;
 	}
@@ -69,7 +77,26 @@ protected CentralisedFuture<Void> doForAllPlayers(Consumer<Player> callback) {
 
 	@Override
 	public void kickPlayer(Player player, Component message) {
-		morePaperLibAdventure.kickPlayer(player, message);
+		if (configs.getMainConfig().platforms().bukkit().kickViaPluginMessaging()) {
+			byte[] kickData;
+			try (ByteArrayOutputStream kickDataStream = new ByteArrayOutputStream();
+				 DataOutputStream write = new DataOutputStream(kickDataStream)) {
+
+				write.writeUTF("KickPlayer");
+				write.writeUTF(player.getName());
+				write.writeUTF(LegacyComponentSerializer.legacySection().serialize(message));
+				kickData = kickDataStream.toByteArray();
+			} catch (IOException ex) {
+				throw new UncheckedIOException(ex);
+			}
+			player.sendPluginMessage(
+					morePaperLibAdventure.getMorePaperLib().getPlugin(),
+					ChannelRegistration.BUNGEE_CHANNEL,
+					kickData
+			);
+		} else {
+			morePaperLibAdventure.kickPlayer(player, message);
+		}
 	}
 
 	@Override

bans-env/spigot/src/main/java/space/arim/libertybans/env/spigot/SpigotEnv.java

@@ -1,6 +1,6 @@
 /*
  * LibertyBans
- * Copyright © 2022 Anand Beh
+ * Copyright © 2023 Anand Beh
  *
  * LibertyBans is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
@@ -32,22 +32,24 @@ public final class SpigotEnv implements Environment {
 	private final Provider<ConnectionListener> connectionListener;
 	private final Provider<ChatListener> chatListener;
 	private final CommandHandler.CommandHelper commandHelper;
+	private final ChannelRegistration channelRegistration;
 
 	@Inject
-	public SpigotEnv(Provider<ConnectionListener> connectionListener,
-					 Provider<ChatListener> chatListener,
-					 CommandHandler.CommandHelper commandHelper) {
+	public SpigotEnv(Provider<ConnectionListener> connectionListener, Provider<ChatListener> chatListener,
+					 CommandHandler.CommandHelper commandHelper, ChannelRegistration channelRegistration) {
 		this.connectionListener = connectionListener;
 		this.chatListener = chatListener;
 		this.commandHelper = commandHelper;
+		this.channelRegistration = channelRegistration;
 	}
 
 	@Override
 	public Set<PlatformListener> createListeners() {
 		return Set.of(
 				connectionListener.get(),
 				chatListener.get(),
-				new CommandHandler(commandHelper, Commands.BASE_COMMAND_NAME, false)
+				new CommandHandler(commandHelper, Commands.BASE_COMMAND_NAME, false),
+				channelRegistration
 		);
 	}