Plugin message helper for the spigot plugin

.circleci/config.yml

@@ -44,4 +44,6 @@ jobs:
           path: target/surefire-reports
 
       - store_artifacts:
-          path: target/PlayerBalancer.jar
+          paths:
+            - target/PlayerBalancer.jar
+            - target/PlayerBalancerAddon.jar

Main Plugin/pom.xml

@@ -36,6 +36,14 @@
                     </execution>
                 </executions>
             </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-jar-plugin</artifactId>
+                <version>2.3.1</version>
+                <configuration>
+                    <outputDirectory>../target</outputDirectory>
+                </configuration>
+            </plugin>
         </plugins>
     </build>
 

Main Plugin/src/main/java/com/jaimemartz/playerbalancer/listener/PluginMessageListener.java

@@ -111,6 +111,29 @@ public class PluginMessageListener implements Listener {
                     sender.sendData("PlayerBalancer", stream.toByteArray());
                     break;
                 }
+
+                case "GetSectionOfPlayer": {
+                    if (event.getReceiver() instanceof ProxiedPlayer) {
+                        ProxiedPlayer player = (ProxiedPlayer) event.getReceiver();
+                        ByteArrayOutputStream stream = new ByteArrayOutputStream();
+                        DataOutputStream out = new DataOutputStream(stream);
+
+                        ServerSection section = plugin.getSectionManager().getByPlayer(player);
+                        if (section == null) {
+                            return;
+                        }
+
+                        try {
+                            String output = gson.toJson(section);
+                            out.writeUTF(output);
+                        } catch (IOException e) {
+                            e.printStackTrace();
+                        }
+
+                        sender.sendData("PlayerBalancer", stream.toByteArray());
+                    }
+                    break;
+                }
             }
         }
     }

Spigot Addon/pom.xml

@@ -12,17 +12,31 @@
     <name>PlayerBalancer Addon</name>
     <artifactId>playerbalancer-addon</artifactId>
 
+    <build>
+        <finalName>PlayerBalancerAddon</finalName>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-jar-plugin</artifactId>
+                <version>2.3.1</version>
+                <configuration>
+                    <outputDirectory>../target</outputDirectory>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
     <repositories>
         <repository>
             <id>spigot-repo</id>
             <url>https://hub.spigotmc.org/nexus/content/repositories/snapshots/</url>
         </repository>
+        <repository>
+            <id>placeholderapi</id>
+            <url>http://repo.extendedclip.com/content/repositories/placeholderapi/</url>
+        </repository>
     </repositories>
 
-    <build>
-        <finalName>PlayerBalancerAddon</finalName>
-    </build>
-
     <dependencies>
         <dependency>
             <groupId>org.spigotmc</groupId>
@@ -30,5 +44,11 @@
             <version>1.12.2-R0.1-SNAPSHOT</version>
             <scope>provided</scope>
         </dependency>
+        <dependency>
+            <groupId>me.clip</groupId>
+            <artifactId>placeholderapi</artifactId>
+            <version>2.8.2</version>
+            <scope>provided</scope>
+        </dependency>
     </dependencies>
 </project>

Spigot Addon/src/main/java/com/jaimemartz/playerbalanceraddon/MainCommand.java

@@ -0,0 +1,18 @@
+package com.jaimemartz.playerbalanceraddon;
+
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandExecutor;
+import org.bukkit.command.CommandSender;
+
+public class MainCommand implements CommandExecutor {
+    private final PlayerBalancerAddon plugin;
+
+    public MainCommand(PlayerBalancerAddon plugin) {
+        this.plugin = plugin;
+    }
+
+    @Override
+    public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args) {
+        return false;
+    }
+}

Spigot Addon/src/main/java/com/jaimemartz/playerbalanceraddon/PlayerBalancerAddon.java

@@ -3,13 +3,20 @@ package com.jaimemartz.playerbalanceraddon;
 import org.bukkit.plugin.java.JavaPlugin;
 
 public class PlayerBalancerAddon extends JavaPlugin {
+    private PluginMessageManager manager;
+
     @Override
     public void onDisable() {
-
+        manager = new PluginMessageManager(this);
+        getCommand("balancer").setExecutor(new MainCommand(this));
     }
 
     @Override
     public void onEnable() {
 
     }
+
+    public PluginMessageManager getManager() {
+        return manager;
+    }
 }

Spigot Addon/src/main/java/com/jaimemartz/playerbalanceraddon/PluginMessageManager.java

@@ -0,0 +1,136 @@
+package com.jaimemartz.playerbalanceraddon;
+
+import com.google.common.collect.ArrayListMultimap;
+import com.google.common.collect.Iterables;
+import com.google.common.collect.LinkedListMultimap;
+import com.google.common.collect.Multimap;
+import com.google.common.io.ByteArrayDataInput;
+import com.google.common.io.ByteArrayDataOutput;
+import com.google.common.io.ByteStreams;
+import org.bukkit.Bukkit;
+import org.bukkit.entity.Player;
+import org.bukkit.plugin.messaging.Messenger;
+import org.bukkit.plugin.messaging.PluginMessageListener;
+
+import java.io.ByteArrayOutputStream;
+import java.io.DataInputStream;
+import java.util.*;
+import java.util.function.Consumer;
+
+public class PluginMessageManager implements PluginMessageListener {
+    private final Multimap<MessageContext, Consumer<ByteArrayDataInput>> contexts = LinkedListMultimap.create();
+    private final PlayerBalancerAddon plugin;
+
+    public PluginMessageManager(PlayerBalancerAddon plugin) {
+        this.plugin = plugin;
+
+        plugin.getServer().getMessenger().registerIncomingPluginChannel(plugin, "PlayerBalancer", this);
+        plugin.getServer().getMessenger().registerOutgoingPluginChannel(plugin, "PlayerBalancer");
+
+        //In case we need to use BungeeCord channels
+        plugin.getServer().getMessenger().registerIncomingPluginChannel(plugin, "BungeeCord", this);
+        plugin.getServer().getMessenger().registerOutgoingPluginChannel(plugin, "BungeeCord");
+    }
+
+    @Override
+    public void onPluginMessageReceived(String channel, Player player, byte[] message) {
+        if (channel.equals("PlayerBalancer")) {
+            ByteArrayDataInput in = ByteStreams.newDataInput(message);
+            String subchannel = in.readUTF();
+
+            contexts.get(new MessageContext(channel, subchannel, player))
+                    .stream().findFirst().ifPresent(a -> a.accept(in));
+        }
+    }
+
+    public void connectPlayer(Player player, String section) {
+        ByteArrayDataOutput out = ByteStreams.newDataOutput();
+        out.writeUTF("Connect");
+        out.writeUTF(section);
+        player.sendPluginMessage(plugin, "PlayerBalancer", out.toByteArray());
+    }
+
+    public boolean getSectionByName(String section, Consumer<String> consumer) {
+        Player player = Iterables.getFirst(plugin.getServer().getOnlinePlayers(), null);
+        if (player == null) {
+            return false;
+        }
+
+        ByteArrayDataOutput out = ByteStreams.newDataOutput();
+        out.writeUTF("GetSectionByName");
+        out.writeUTF(section);
+        player.sendPluginMessage(plugin, "PlayerBalancer", out.toByteArray());
+
+        contexts.put(new MessageContext(
+                "PlayerBalancer",
+                "GetSectionByName",
+                player
+        ), ByteArrayDataInput::readUTF);
+
+        return true;
+    }
+
+    public boolean getSectionByServer(String server, Consumer<String> consumer) {
+        Player player = Iterables.getFirst(plugin.getServer().getOnlinePlayers(), null);
+        if (player == null) {
+            return false;
+        }
+
+        ByteArrayDataOutput out = ByteStreams.newDataOutput();
+        out.writeUTF("GetSectionByServer");
+        out.writeUTF(server);
+        player.sendPluginMessage(plugin, "PlayerBalancer", out.toByteArray());
+
+        contexts.put(new MessageContext(
+                "PlayerBalancer",
+                "GetSectionByServer",
+                player
+        ), ByteArrayDataInput::readUTF);
+        return true;
+    }
+
+    public void getSectionOfPlayer(Player player, Consumer<String> consumer) {
+        ByteArrayDataOutput out = ByteStreams.newDataOutput();
+        out.writeUTF("GetSectionOfPlayer");
+        out.writeUTF(player.getName());
+        player.sendPluginMessage(plugin, "PlayerBalancer", out.toByteArray());
+
+        contexts.put(new MessageContext(
+                "PlayerBalancer",
+                "GetSectionOfPlayer",
+                player
+        ), ByteArrayDataInput::readUTF);
+    }
+
+    private final class MessageContext {
+        private final String channel;
+        private final String subchannel;
+        private final Player player;
+
+        public MessageContext(String channel, String subchannel, Player player) {
+            this.channel = channel;
+            this.subchannel = subchannel;
+            this.player = player;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (o == null || getClass() != o.getClass()) return false;
+
+            MessageContext that = (MessageContext) o;
+
+            if (channel != null ? !channel.equals(that.channel) : that.channel != null) return false;
+            if (subchannel != null ? !subchannel.equals(that.subchannel) : that.subchannel != null) return false;
+            return player != null ? player.equals(that.player) : that.player == null;
+        }
+
+        @Override
+        public int hashCode() {
+            int result = channel != null ? channel.hashCode() : 0;
+            result = 31 * result + (subchannel != null ? subchannel.hashCode() : 0);
+            result = 31 * result + (player != null ? player.hashCode() : 0);
+            return result;
+        }
+    }
+}