Packet, Auth reworks & Messages

Lib/src/main/java/dev/wiing/gossip/lib/PacketHandler.java

@@ -1,8 +1,9 @@
 package dev.wiing.gossip.lib;
 
-import dev.wiing.gossip.lib.packets.CreateTopicPacket;
+import dev.wiing.gossip.lib.packets.MessageCreatedPacket;
 import dev.wiing.gossip.lib.packets.Packet;
-import dev.wiing.gossip.lib.packets.TopicAddedPacket;
+import dev.wiing.gossip.lib.packets.TopicCreatedPacket;
+import dev.wiing.gossip.lib.packets.TopicUpdatePacket;
 
 import java.util.*;
 import java.util.concurrent.ConcurrentHashMap;
@@ -28,22 +29,30 @@ public class PacketHandler {
         listeners.get(type).remove(listener);
     }
 
-    public <T extends Packet> void runPacket(Class<T> packetClass, T packet) {
+    public <T extends Packet> boolean runPacket(Class<T> packetClass, T packet) {
         Set<PacketListener<T>> result = getListeners(packetClass);
 
-        if (result == null) return;
+        if (result == null || result.isEmpty()) return false;
 
         for (PacketListener<T> packetListener : result) {
             packetListener.onReceive(packet);
         }
+
+        return true;
     }
 
-    public void runPacket(Packet packet) {
+    public boolean runPacket(Packet packet) {
         switch (packet.getType()) {
-            case TopicAddedPacket.TYPE:
-                runPacket(TopicAddedPacket.class, (TopicAddedPacket)packet);
-                break;
+            case TopicCreatedPacket.TYPE:
+                return runPacket(TopicCreatedPacket.class, (TopicCreatedPacket)packet);
+
+            case TopicUpdatePacket.TYPE:
+                return runPacket(TopicUpdatePacket.class, (TopicUpdatePacket)packet);
+
+            case MessageCreatedPacket.TYPE:
+                return runPacket(MessageCreatedPacket.class, (MessageCreatedPacket)packet);
         }
+        return false;
     }
 
     public <T extends Packet> Set<PacketListener<T>> getListeners(Class<T> packetClass) {
@@ -55,4 +64,14 @@ public class PacketHandler {
         }).collect(Collectors.toSet());
     }
 
+    public List<Short> getListeningTypes() {
+        return new ArrayList<>() {
+            {
+                add(TopicCreatedPacket.TYPE);
+                add(TopicUpdatePacket.TYPE);
+                add(MessageCreatedPacket.TYPE);
+            }
+        };
+    }
+
 }

Lib/src/main/java/dev/wiing/gossip/lib/PacketManager.java

@@ -14,15 +14,21 @@ public class PacketManager {
     private final List<Packet> packetList = new ArrayList<>() {
         {
             add(new TestPacket());
+            add(new AckPacket());
 
-            add(new RegisterPacket());
-            add(new CredentialsPacket());
+            add(new RegisterRequestPacket());
+            add(new RegisterCredentialsPacket());
 
-            add(new CreateTopicPacket());
-            add(new TopicAddedPacket());
+            add(new TopicPushPacket());
+            add(new TopicCreatedPacket());
+            add(new TopicJoinPacket());
+            add(new TopicUpdatePacket());
 
-            add(new FetchUserPacket());
+            add(new UserFetchPacket());
             add(new UserDataPacket());
+
+            add(new MessagePushPacket());
+            add(new MessageCreatedPacket());
         }
     };
 

Lib/src/main/java/dev/wiing/gossip/lib/data/AuthSecret.java

@@ -0,0 +1,47 @@
+package dev.wiing.gossip.lib.data;
+
+import java.nio.ByteBuffer;
+import java.util.List;
+
+public class AuthSecret {
+
+    public static final int LENGTH = 32;
+
+    private byte[] value = new byte[LENGTH];
+
+    public AuthSecret(byte... value) {
+        if (value.length != LENGTH)
+            throw new RuntimeException("Invalid length");
+
+        this.value = value;
+    }
+
+    public AuthSecret(Byte... value) {
+        if (value.length != LENGTH)
+            throw new RuntimeException("Invalid length");
+
+        for (int i = 0; i < value.length; i++) {
+            this.value[i] = value[i];
+        }
+    }
+
+    public AuthSecret(List<Byte> value) {
+        this(value.toArray(new Byte[32]));
+    }
+
+    public AuthSecret(String value) {
+        this(value.getBytes());
+    }
+
+    public AuthSecret(ByteBuffer buffer) {
+        buffer.get(value);
+    }
+
+    public byte[] getBytes() {
+        return value;
+    }
+
+    public String getString() {
+        return new String(value);
+    }
+}

Lib/src/main/java/dev/wiing/gossip/lib/data/ListData.java

@@ -0,0 +1,60 @@
+package dev.wiing.gossip.lib.data;
+
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.function.Function;
+
+public class ListData<T extends PacketData> implements PacketData {
+
+    @FunctionalInterface
+    public interface ListDataInitializer<U> {
+        U create();
+    }
+
+    private final ListDataInitializer<T> entryInitializer;
+
+    private final List<T> data = new ArrayList<>();
+
+    public ListData(ListDataInitializer<T> entryInitializer) {
+        this.entryInitializer = entryInitializer;
+    }
+
+    public List<T> getData() {
+        return data;
+    }
+
+    @Override
+    public int getLength() {
+        return 4 + data.stream()
+                .map(PacketData::getLength)
+                .reduce(0, Integer::sum);
+    }
+
+    @Override
+    public ByteBuffer getBytes() {
+        ByteBuffer buffer = ByteBuffer.allocate(getLength());
+
+        buffer.putInt(data.size());
+
+        for (T datum : data) {
+            buffer.put(datum.getBytes());
+        }
+
+        return buffer.rewind();
+    }
+
+    @Override
+    public void setBytes(ByteBuffer buffer) {
+        this.data.clear();
+
+        int size = buffer.getInt();
+
+        for (; size > 0; --size) {
+            T entry = entryInitializer.create();
+            entry.setBytes(buffer);
+            this.data.add(entry);
+        }
+    }
+}

Lib/src/main/java/dev/wiing/gossip/lib/data/LongData.java

@@ -0,0 +1,34 @@
+package dev.wiing.gossip.lib.data;
+
+import java.nio.ByteBuffer;
+
+public class LongData implements PacketAtomicData<Long> {
+
+    private long value = 0;
+
+    @Override
+    public Long getValue() {
+        return value;
+    }
+
+    @Override
+    public LongData setValue(Long value) {
+        this.value = value;
+        return this;
+    }
+
+    @Override
+    public int getLength() {
+        return 8;
+    }
+
+    @Override
+    public ByteBuffer getBytes() {
+        return ByteBuffer.allocate(getLength()).putLong(value).rewind();
+    }
+
+    @Override
+    public void setBytes(ByteBuffer buffer) {
+        value = buffer.getLong();
+    }
+}

Lib/src/main/java/dev/wiing/gossip/lib/data/PacketAtomicData.java

@@ -0,0 +1,6 @@
+package dev.wiing.gossip.lib.data;
+
+public interface PacketAtomicData<T> extends PacketData {
+    T getValue();
+    PacketAtomicData<T> setValue(T value);
+}

Lib/src/main/java/dev/wiing/gossip/lib/data/PacketData.java

@@ -1,13 +1,8 @@
 package dev.wiing.gossip.lib.data;
 
-import java.io.ByteArrayInputStream;
 import java.nio.ByteBuffer;
 
-public interface DataType<T> {
-
-    T getValue();
-    void setValue(T val);
-
+public interface PacketData {
     int getLength();
 
     ByteBuffer getBytes();

Lib/src/main/java/dev/wiing/gossip/lib/data/StringData.java

@@ -1,11 +1,9 @@
 package dev.wiing.gossip.lib.data;
 
-import java.io.ByteArrayInputStream;
-import java.io.ByteArrayOutputStream;
 import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
 
-public class StringType implements DataType<String> {
+public class StringData implements PacketAtomicData<String> {
 
     private String value = "";
 
@@ -15,8 +13,9 @@ public class StringType implements DataType<String> {
     }
 
     @Override
-    public void setValue(String val) {
+    public StringData setValue(String val) {
         this.value = val;
+        return this;
     }
 
     @Override

Lib/src/main/java/dev/wiing/gossip/lib/models/Message.java

@@ -3,15 +3,35 @@ package dev.wiing.gossip.lib.models;
 import java.time.LocalDateTime;
 
 public class Message {
-    private User author;
-    private String message;
-    private LocalDateTime postTime;
+    private final User author;
+    private final Topic topic;
+    private final String contents;
+    private final LocalDateTime postTime;
 
-    public Message(User author, String message, LocalDateTime postTime) {
+    public Message(User author, Topic topic, String contents, LocalDateTime postTime) {
         this.author = author;
-        this.message = message;
+        this.topic = topic;
+        this.contents = contents;
         this.postTime = postTime;
     }
 
+    public Message(User author, Topic topic, String contents) {
+        this(author, topic, contents, LocalDateTime.now());
+    }
 
+    public User getAuthor() {
+        return author;
+    }
+
+    public Topic getTopic() {
+        return topic;
+    }
+
+    public String getContents() {
+        return contents;
+    }
+
+    public LocalDateTime getPostTime() {
+        return postTime;
+    }
 }

Lib/src/main/java/dev/wiing/gossip/lib/models/SecretUser.java

@@ -1,14 +1,17 @@
 package dev.wiing.gossip.lib.models;
 
-public class SecretUser extends User {
-    private final byte[] userSecret;
+import dev.wiing.gossip.lib.data.AuthSecret;
+import dev.wiing.gossip.lib.models.User;
 
-    public SecretUser(String username, int iconID, long userID, byte[] userSecret) {
+public class SecretUser extends User {
+    private final AuthSecret userSecret;
+
+    public SecretUser(String username, int iconID, long userID, AuthSecret userSecret) {
         super(username, iconID, userID);
         this.userSecret = userSecret;
     }
 
-    public byte[] getUserSecret() {
+    public AuthSecret getUserSecret() {
         return userSecret;
     }
 }

Lib/src/main/java/dev/wiing/gossip/lib/models/Topic.java

@@ -2,8 +2,7 @@ package dev.wiing.gossip.lib.models;
 
 import java.beans.PropertyChangeListener;
 import java.beans.PropertyChangeSupport;
-import java.util.Collections;
-import java.util.Map;
+import java.util.*;
 import java.util.concurrent.ConcurrentHashMap;
 
 public class Topic {
@@ -16,6 +15,8 @@ public class Topic {
     private final Map<Long, User> users = new ConcurrentHashMap<>();
     private short color;
 
+    private final List<Message> messages = Collections.synchronizedList(new ArrayList<>());
+
     public Topic(long id, String name, String description, User host, short color) {
         this.id = id;
         this.name = name;
@@ -72,20 +73,30 @@ public class Topic {
         if (this.users.containsKey(user.getUserID())) return;
 
         this.users.put(user.getUserID(), user);
-        this.changeSupport.firePropertyChange("userAdd", null, getUsersReadOnly());
+        this.changeSupport.firePropertyChange("userAdd", user, null);
     }
 
     public void removeUser(User user) {
         if (!this.users.containsKey(user.getUserID())) return;
 
         this.users.remove(user.getUserID());
-        this.changeSupport.firePropertyChange("userRemove", null, getUsersReadOnly());
+        this.changeSupport.firePropertyChange("userRemove", null, user);
     }
 
     public boolean hasUser(User user) {
         return this.users.containsKey(user.getUserID());
     }
 
+    public List<Message> getMessagesReadOnly() {
+        return Collections.unmodifiableList(messages);
+    }
+
+    public void addMessage(Message message) {
+        messages.add(message);
+
+        this.changeSupport.firePropertyChange("messageAdd", null, message);
+    }
+
     public void addChangeListener(PropertyChangeListener listener) {
         this.changeSupport.addPropertyChangeListener(listener);
     }

Lib/src/main/java/dev/wiing/gossip/lib/packets/AckPacket.java

@@ -0,0 +1,41 @@
+package dev.wiing.gossip.lib.packets;
+
+import java.nio.ByteBuffer;
+
+public class AckPacket extends Packet {
+
+    public static final short TYPE = 0x02;
+    public static final int LENGTH = 0x002;
+
+    private short acknowledgement;
+
+    public AckPacket() {
+        super(TYPE, LENGTH);
+    }
+
+    public short getAcknowledgement() {
+        return acknowledgement;
+    }
+
+    public void setAcknowledgement(short acknowledgement) {
+        this.acknowledgement = acknowledgement;
+    }
+
+    public void setAcknowledgement(Packet packet) {
+        setAcknowledgement(packet.getType());
+    }
+
+    @Override
+    public Packet readBytes(ByteBuffer buffer, int size) {
+        AckPacket packet = new AckPacket();
+
+        packet.acknowledgement = buffer.getShort();
+
+        return packet;
+    }
+
+    @Override
+    public void writeBytes(ByteBuffer buffer) {
+        buffer.putShort(acknowledgement);
+    }
+}

Lib/src/main/java/dev/wiing/gossip/lib/packets/AuthRequiredPacket.java

@@ -0,0 +1,19 @@
+package dev.wiing.gossip.lib.packets;
+
+import dev.wiing.gossip.lib.data.AuthSecret;
+
+public abstract class AuthRequiredPacket extends Packet {
+    private AuthSecret auth;
+
+    public AuthRequiredPacket(short type, int length) {
+        super(type, length);
+    }
+
+    public AuthSecret getAuth() {
+        return auth;
+    }
+
+    public void setAuth(AuthSecret auth) {
+        this.auth = auth;
+    }
+}

Lib/src/main/java/dev/wiing/gossip/lib/packets/MessageCreatedPacket.java

@@ -0,0 +1,63 @@
+package dev.wiing.gossip.lib.packets;
+
+import dev.wiing.gossip.lib.data.StringData;
+
+import java.nio.ByteBuffer;
+
+public class MessageCreatedPacket extends Packet {
+
+    public static final short TYPE = 0x32;
+    public static final int LENGTH = 0x014;
+
+    private long authorID;
+    private long topicID;
+    private final StringData contents = new StringData();
+
+    public MessageCreatedPacket() {
+        super(TYPE, LENGTH);
+    }
+
+    public long getAuthorID() {
+        return authorID;
+    }
+
+    public void setAuthorID(long authorID) {
+        this.authorID = authorID;
+    }
+
+    public long getTopicID() {
+        return topicID;
+    }
+
+    public void setTopicID(long topicID) {
+        this.topicID = topicID;
+    }
+
+    public String getContents() {
+        return contents.getValue();
+    }
+
+    public void setContents(String contents) {
+        this.contents.setValue(contents);
+        setLength(16 + this.contents.getLength());
+    }
+
+    @Override
+    public Packet readBytes(ByteBuffer buffer, int size) {
+        MessageCreatedPacket packet = new MessageCreatedPacket();
+        packet.setLength(size);
+
+        packet.authorID = buffer.getLong();
+        packet.topicID = buffer.getLong();
+        packet.contents.setBytes(buffer);
+
+        return packet;
+    }
+
+    @Override
+    public void writeBytes(ByteBuffer buffer) {
+        buffer.putLong(authorID);
+        buffer.putLong(topicID);
+        buffer.put(contents.getBytes());
+    }
+}

Lib/src/main/java/dev/wiing/gossip/lib/packets/MessagePushPacket.java

@@ -0,0 +1,54 @@
+package dev.wiing.gossip.lib.packets;
+
+import dev.wiing.gossip.lib.data.AuthSecret;
+import dev.wiing.gossip.lib.data.StringData;
+
+import java.nio.ByteBuffer;
+
+public class MessagePushPacket extends AuthRequiredPacket {
+    public static final short TYPE = 0x31;
+    public static final int LENGTH = 0x02C;
+
+    private long topicID;
+    private final StringData message = new StringData();
+
+    public MessagePushPacket() {
+        super(TYPE, LENGTH);
+    }
+
+    public long getTopicID() {
+        return topicID;
+    }
+
+    public void setTopicID(long topicID) {
+        this.topicID = topicID;
+    }
+
+    public String getMessage() {
+        return message.getValue();
+    }
+
+    public void setMessage(String message) {
+        this.message.setValue(message);
+        setLength(40 + this.message.getLength());
+    }
+
+    @Override
+    public Packet readBytes(ByteBuffer buffer, int size) {
+        MessagePushPacket packet = new MessagePushPacket();
+        packet.setLength(size);
+
+        packet.setAuth(new AuthSecret(buffer));
+        packet.topicID = buffer.getLong();
+        packet.message.setBytes(buffer);
+
+        return packet;
+    }
+
+    @Override
+    public void writeBytes(ByteBuffer buffer) {
+        buffer.put(getAuth().getBytes());
+        buffer.putLong(topicID);
+        buffer.put(message.getBytes());
+    }
+}

Lib/src/main/java/dev/wiing/gossip/lib/packets/RegisterCredentialsPacket.java

@@ -1,24 +1,26 @@
 package dev.wiing.gossip.lib.packets;
 
+import dev.wiing.gossip.lib.data.AuthSecret;
+
 import java.nio.ByteBuffer;
 
-public class CredentialsPacket extends Packet {
+public class RegisterCredentialsPacket extends Packet {
 
-    public static short TYPE = 0x03;
+    public static short TYPE = 0x04;
     public static int LENGTH = 0x028;
 
-    private byte[] secret = new byte[32];
+    private AuthSecret secret;
     private long uID;
 
-    public CredentialsPacket() {
+    public RegisterCredentialsPacket() {
         super(TYPE, LENGTH);
     }
 
-    public byte[] getSecret() {
+    public AuthSecret getSecret() {
         return secret;
     }
 
-    public void setSecret(byte[] secret) {
+    public void setSecret(AuthSecret secret) {
         this.secret = secret;
     }
 
@@ -32,9 +34,9 @@ public class CredentialsPacket extends Packet {
 
     @Override
     public Packet readBytes(ByteBuffer buffer, int size) {
-        CredentialsPacket packet = new CredentialsPacket();
+        RegisterCredentialsPacket packet = new RegisterCredentialsPacket();
 
-        buffer.get(packet.secret);
+        packet.secret = new AuthSecret(buffer);
         packet.setUID(buffer.getLong());
 
         return packet;
@@ -42,7 +44,7 @@ public class CredentialsPacket extends Packet {
 
     @Override
     public void writeBytes(ByteBuffer buffer) {
-        buffer.put(getSecret());
+        buffer.put(getSecret().getBytes());
         buffer.putLong(getUID());
     }
 }

Lib/src/main/java/dev/wiing/gossip/lib/packets/RegisterRequestPacket.java

@@ -1,24 +1,24 @@
 package dev.wiing.gossip.lib.packets;
 
-import dev.wiing.gossip.lib.data.StringType;
+import dev.wiing.gossip.lib.data.StringData;
 
 import java.nio.ByteBuffer;
 
-public class RegisterPacket extends Packet {
+public class RegisterRequestPacket extends Packet {
 
-    public static final short TYPE = 0x02;
+    public static final short TYPE = 0x03;
     public static final int SIZE = 0x0005;
 
-    private final StringType username = new StringType();
+    private final StringData username = new StringData();
     private byte avatarID;
 
-    public RegisterPacket() {
+    public RegisterRequestPacket() {
         super(TYPE, SIZE);
     }
 
     @Override
     public Packet readBytes(ByteBuffer buffer, int size) {
-        RegisterPacket packet = new RegisterPacket();
+        RegisterRequestPacket packet = new RegisterRequestPacket();
         packet.setLength(size);
 
         packet.username.setBytes(buffer);

Lib/src/main/java/dev/wiing/gossip/lib/packets/TestPacket.java

@@ -1,8 +1,7 @@
 package dev.wiing.gossip.lib.packets;
 
-import dev.wiing.gossip.lib.data.StringType;
+import dev.wiing.gossip.lib.data.StringData;
 
-import java.io.ByteArrayInputStream;
 import java.nio.ByteBuffer;
 
 public class TestPacket extends Packet {
@@ -10,7 +9,7 @@ public class TestPacket extends Packet {
     public static final short TYPE = 0x01;
     public static final int SIZE = 0x0000;
 
-    private final StringType message = new StringType();
+    private final StringData message = new StringData();
 
     public TestPacket() {
         super(TYPE, SIZE);

Lib/src/main/java/dev/wiing/gossip/lib/packets/TopicCreatedPacket.java

@@ -1,21 +1,21 @@
 package dev.wiing.gossip.lib.packets;
 
-import dev.wiing.gossip.lib.data.StringType;
+import dev.wiing.gossip.lib.data.StringData;
 
 import java.nio.ByteBuffer;
 
-public class TopicAddedPacket extends Packet {
+public class TopicCreatedPacket extends Packet {
 
     public static final short TYPE = 0x12;
     public static final int LENGTH = 0x014;
 
     private long topicID;
     private long hostID;
-    private final StringType topicName = new StringType();
-    private final StringType topicDescription = new StringType();
+    private final StringData topicName = new StringData();
+    private final StringData topicDescription = new StringData();
     private short topicColor;
 
-    public TopicAddedPacket() {
+    public TopicCreatedPacket() {
         super(TYPE, LENGTH);
     }
 
@@ -73,7 +73,7 @@ public class TopicAddedPacket extends Packet {
 
     @Override
     public Packet readBytes(ByteBuffer buffer, int size) {
-        TopicAddedPacket packet = new TopicAddedPacket();
+        TopicCreatedPacket packet = new TopicCreatedPacket();
         setLength(size);
 
         packet.topicID = buffer.getLong();

Lib/src/main/java/dev/wiing/gossip/lib/packets/TopicJoinPacket.java

@@ -0,0 +1,41 @@
+package dev.wiing.gossip.lib.packets;
+
+import dev.wiing.gossip.lib.data.AuthSecret;
+
+import java.nio.ByteBuffer;
+
+public class TopicJoinPacket extends AuthRequiredPacket {
+
+    public static final short TYPE = 0x13;
+    public static final int LENGTH = 0x028;
+
+    private long topicID;
+
+    public TopicJoinPacket() {
+        super(TYPE, LENGTH);
+    }
+
+    public long getTopicID() {
+        return topicID;
+    }
+
+    public void setTopicID(long topicID) {
+        this.topicID = topicID;
+    }
+
+    @Override
+    public Packet readBytes(ByteBuffer buffer, int size) {
+        TopicJoinPacket packet = new TopicJoinPacket();
+
+        packet.setAuth(new AuthSecret(buffer));
+        packet.topicID = buffer.getLong();
+
+        return packet;
+    }
+
+    @Override
+    public void writeBytes(ByteBuffer buffer) {
+        buffer.put(getAuth().getBytes());
+        buffer.putLong(topicID);
+    }
+}

Lib/src/main/java/dev/wiing/gossip/lib/packets/TopicPushPacket.java

@@ -1,19 +1,19 @@
 package dev.wiing.gossip.lib.packets;
 
-import dev.wiing.gossip.lib.data.StringType;
+import dev.wiing.gossip.lib.data.AuthSecret;
+import dev.wiing.gossip.lib.data.StringData;
 
 import java.nio.ByteBuffer;
 
-public class CreateTopicPacket extends Packet {
+public class TopicPushPacket extends AuthRequiredPacket {
 
     public static final short TYPE = 0x11;
     public static final int LENGTH = 0x022;
 
-    private byte[] userSecret = new byte[32];
-    private final StringType topicName = new StringType();
-    private final StringType topicDescription = new StringType();
+    private final StringData topicName = new StringData();
+    private final StringData topicDescription = new StringData();
 
-    public CreateTopicPacket() {
+    public TopicPushPacket() {
         super(TYPE, LENGTH);
     }
 
@@ -25,14 +25,6 @@ public class CreateTopicPacket extends Packet {
         );
     }
 
-    public byte[] getUserSecret() {
-        return userSecret;
-    }
-
-    public void setUserSecret(byte[] userSecret) {
-        this.userSecret = userSecret;
-    }
-
     public String getTopicName() {
         return topicName.getValue();
     }
@@ -53,10 +45,10 @@ public class CreateTopicPacket extends Packet {
 
     @Override
     public Packet readBytes(ByteBuffer buffer, int size) {
-        CreateTopicPacket packet = new CreateTopicPacket();
+        TopicPushPacket packet = new TopicPushPacket();
         packet.setLength(size);
 
-        buffer.get(packet.userSecret);
+        packet.setAuth(new AuthSecret(buffer));
         packet.topicName.setBytes(buffer);
         packet.topicDescription.setBytes(buffer);
 
@@ -65,7 +57,7 @@ public class CreateTopicPacket extends Packet {
 
     @Override
     public void writeBytes(ByteBuffer buffer) {
-        buffer.put(userSecret);
+        buffer.put(getAuth().getBytes());
         buffer.put(topicName.getBytes());
         buffer.put(topicDescription.getBytes());
     }

Lib/src/main/java/dev/wiing/gossip/lib/packets/TopicUpdatePacket.java

@@ -0,0 +1,138 @@
+package dev.wiing.gossip.lib.packets;
+
+import dev.wiing.gossip.lib.data.ListData;
+import dev.wiing.gossip.lib.data.LongData;
+import dev.wiing.gossip.lib.data.StringData;
+
+import java.nio.ByteBuffer;
+import java.util.List;
+
+public class TopicUpdatePacket extends Packet {
+    public static final short TYPE = 0x14;
+    public static final int LENGTH = 0x009;
+
+    private long topicID;
+    private byte updateFlags = 0;
+
+    // FLAG 0b0001 == 0x1
+    public static final byte FLAG_TOPIC_NAME_UPDATED = 0b1;
+    private final StringData topicName = new StringData();
+
+    // FLAG 0b0010 == 0x2
+    public static final byte FLAG_TOPIC_DESCRIPTION_UPDATED = 0b10;
+    private final StringData topicDescription = new StringData();
+
+    // FLAG 0b0100 == 0x4
+    public static final byte FLAG_USERS_JOINED = 0b100;
+    private final ListData<LongData> usersJoined = new ListData<>(LongData::new);
+
+    // FLAG 0b1000 == 0x8
+    public static final byte FLAG_USERS_LEFT = 0b1000;
+    private final ListData<LongData> usersLeft = new ListData<>(LongData::new);
+
+    public TopicUpdatePacket() {
+        super(TYPE, LENGTH);
+    }
+
+    private void updateLength() {
+        if (!usersJoined.getData().isEmpty()) {
+            updateFlags |= FLAG_USERS_JOINED;
+        }
+        if (!usersLeft.getData().isEmpty()) {
+            updateFlags |= FLAG_USERS_LEFT;
+        }
+
+        setLength(9 +
+                (isTopicNameModified() ? topicName.getLength() : 0) +
+                (isTopicDescriptionModified() ? topicDescription.getLength() : 0) +
+                (haveUsersJoined() ? usersJoined.getLength() : 0) +
+                (haveUsersLeft() ? usersLeft.getLength() : 0));
+    }
+
+    @Override
+    public int getLength() {
+        updateLength();
+        return super.getLength();
+    }
+
+    public long getTopicID() {
+        return topicID;
+    }
+
+    public void setTopicID(long topicID) {
+        this.topicID = topicID;
+    }
+
+    public boolean isTopicNameModified() {
+        return (updateFlags & FLAG_TOPIC_NAME_UPDATED) > 0;
+    }
+
+    public boolean isTopicDescriptionModified() {
+        return (updateFlags & FLAG_TOPIC_DESCRIPTION_UPDATED) > 0;
+    }
+
+    public boolean haveUsersJoined() {
+        return (updateFlags & FLAG_USERS_JOINED) > 0;
+    }
+
+    public boolean haveUsersLeft() {
+        return (updateFlags & FLAG_USERS_LEFT) > 0;
+    }
+
+    public String getTopicName() {
+        return topicName.getValue();
+    }
+
+    public void setTopicName(String topicName) {
+        this.topicName.setValue(topicName);
+        this.updateFlags |= FLAG_TOPIC_NAME_UPDATED;
+        updateLength();
+    }
+
+    public String getTopicDescription() {
+        return topicDescription.getValue();
+    }
+
+    public void setTopicDescription(String topicDescription) {
+        this.topicDescription.setValue(topicDescription);
+        this.updateFlags |= FLAG_TOPIC_DESCRIPTION_UPDATED;
+        updateLength();
+    }
+
+    public List<LongData> getUsersJoined() {
+        return usersJoined.getData();
+    }
+
+    public List<LongData> getUsersLeft() {
+        return usersLeft.getData();
+    }
+
+    @Override
+    public Packet readBytes(ByteBuffer buffer, int size) {
+        TopicUpdatePacket packet = new TopicUpdatePacket();
+        packet.setLength(size);
+
+        packet.topicID = buffer.getLong();
+        packet.updateFlags = buffer.get();
+
+        if (packet.isTopicNameModified()) packet.topicName.setBytes(buffer);
+        if (packet.isTopicDescriptionModified()) packet.topicDescription.setBytes(buffer);
+        if (packet.haveUsersJoined()) packet.usersJoined.setBytes(buffer);
+        if (packet.haveUsersLeft()) packet.usersLeft.setBytes(buffer);
+
+        return packet;
+    }
+
+    @Override
+    public void writeBytes(ByteBuffer buffer) {
+        updateLength();
+
+        buffer.putLong(topicID);
+        buffer.put(updateFlags);
+
+        if (isTopicNameModified()) buffer.put(topicName.getBytes());
+        if (isTopicDescriptionModified()) buffer.put(topicDescription.getBytes());
+        if (haveUsersJoined()) buffer.put(usersJoined.getBytes());
+        if (haveUsersLeft()) buffer.put(usersLeft.getBytes());
+    }
+}

Lib/src/main/java/dev/wiing/gossip/lib/packets/UserDataPacket.java

@@ -1,6 +1,6 @@
 package dev.wiing.gossip.lib.packets;
 
-import dev.wiing.gossip.lib.data.StringType;
+import dev.wiing.gossip.lib.data.StringData;
 
 import java.nio.ByteBuffer;
 
@@ -10,7 +10,7 @@ public class UserDataPacket extends Packet {
     public static final int LENGTH = 0x00a;
 
     private long userID;
-    private final StringType username = new StringType();
+    private final StringData username = new StringData();
     private byte avatarID;
 
     public UserDataPacket() {

Lib/src/main/java/dev/wiing/gossip/lib/packets/UserFetchPacket.java

@@ -2,14 +2,14 @@ package dev.wiing.gossip.lib.packets;
 
 import java.nio.ByteBuffer;
 
-public class FetchUserPacket extends Packet {
+public class UserFetchPacket extends Packet {
 
     public static final short TYPE = 0x21;
     public static final int LENGTH = 0x008;
 
     private long userID;
 
-    public FetchUserPacket() {
+    public UserFetchPacket() {
         super(TYPE, LENGTH);
     }
 
@@ -23,7 +23,7 @@ public class FetchUserPacket extends Packet {
 
     @Override
     public Packet readBytes(ByteBuffer buffer, int size) {
-        FetchUserPacket packet = new FetchUserPacket();
+        UserFetchPacket packet = new UserFetchPacket();
 
         packet.userID = buffer.getLong();