Added plugin system

EonaCat.Connections.Client/Program.cs

@@ -61,7 +61,7 @@ namespace EonaCat.Connections.Client.Example
                 Console.WriteLine($"Connected to server at {e.RemoteEndPoint}");
 
                 // Set nickname
-                await _client.SetNicknameAsync("TestUser");
+                await _client.SendNicknameAsync("TestUser");
 
                 // Send a message
                 await _client.SendAsync("Hello server!");

EonaCat.Connections/DisconnectReason.cs

@@ -0,0 +1,23 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace EonaCat.Connections
+{
+    // This file is part of the EonaCat project(s) which is released under the Apache License.
+    // See the LICENSE file or go to https://EonaCat.com/license for full license details.
+    public enum DisconnectReason
+    {
+        Unknown,
+        RemoteClosed,
+        LocalClosed,
+        Timeout,
+        Error,
+        ServerShutdown,
+        Reconnect,
+        ClientRequested,
+        Forced
+    }
+}

EonaCat.Connections/EonaCat.Connections.csproj

@@ -11,7 +11,7 @@
     <Copyright>EonaCat (Jeroen Saey)</Copyright>
     <PackageReadmeFile>readme.md</PackageReadmeFile>
     <PackageId>EonaCat.Connections</PackageId>
-    <Version>1.0.7</Version>
+    <Version>1.0.8</Version>
     <Authors>EonaCat (Jeroen Saey)</Authors>
     <PackageLicenseFile>LICENSE</PackageLicenseFile>
     <PackageIcon>EonaCat.png</PackageIcon>
@@ -36,6 +36,7 @@
 
   <ItemGroup>
     <PackageReference Include="EonaCat.Json" Version="1.1.9" />
+    <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.6.3" />
   </ItemGroup>
 
 </Project>

EonaCat.Connections/EventArguments/ConnectionEventArgs.cs

@@ -1,4 +1,5 @@
 using System.Net;
+using System.Net.Sockets;
 
 namespace EonaCat.Connections.EventArguments
 {
@@ -9,8 +10,72 @@ namespace EonaCat.Connections.EventArguments
     {
         public string ClientId { get; set; }
         public string Nickname { get; set; }
-        public bool HasNickname => !string.IsNullOrEmpty(Nickname);
         public IPEndPoint RemoteEndPoint { get; set; }
+        public DisconnectReason Reason { get; set; } = DisconnectReason.Unknown;
+        public Exception Exception { get; set; }
+        public bool HasException => Exception != null;
+
+        public bool IsLocalDisconnect =>
+            Reason == DisconnectReason.LocalClosed
+            || Reason == DisconnectReason.Timeout
+            || Reason == DisconnectReason.ServerShutdown
+            || Reason == DisconnectReason.Reconnect
+            || Reason == DisconnectReason.ClientRequested
+            || Reason == DisconnectReason.Forced;
+
+        public bool IsRemoteDisconnect =>
+            Reason == DisconnectReason.RemoteClosed;
+
+        public bool HasNickname => !string.IsNullOrWhiteSpace(Nickname);
+        public bool HasClientId => !string.IsNullOrWhiteSpace(ClientId);
         public DateTime Timestamp { get; set; } = DateTime.UtcNow;
+        public bool HasRemoteEndPoint => RemoteEndPoint != null;
+        public bool IsRemoteEndPointIPv4 => RemoteEndPoint?.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork;
+        public bool HasRemoteEndPointIPv6 => RemoteEndPoint?.AddressFamily == System.Net.Sockets.AddressFamily.InterNetworkV6;
+        public bool IsRemoteEndPointLoopback => RemoteEndPoint != null && IPAddress.IsLoopback(RemoteEndPoint.Address);
+
+
+        public static DisconnectReason Determine(DisconnectReason reason, Exception ex)
+        {
+            if (ex == null)
+            {
+                return reason;
+            }
+
+            if (ex is SocketException socketEx)
+            {
+                switch (socketEx.SocketErrorCode)
+                {
+                    case SocketError.ConnectionReset:
+                    case SocketError.Shutdown:
+                    case SocketError.Disconnecting:
+                        return DisconnectReason.RemoteClosed;
+
+                    case SocketError.TimedOut:
+                        return DisconnectReason.Timeout;
+
+                    case SocketError.NetworkDown:
+                    case SocketError.NetworkReset:
+                    case SocketError.NetworkUnreachable:
+                        return DisconnectReason.Error;
+
+                    default:
+                        return DisconnectReason.Error;
+                }
+            }
+
+            if (ex is ObjectDisposedException || ex is InvalidOperationException)
+            {
+                return DisconnectReason.LocalClosed;
+            }
+
+            if (ex.Message.Contains("An existing connection was forcibly closed by the remote host")
+                || ex.Message.Contains("The remote party has closed the transport stream"))
+            {
+                return DisconnectReason.RemoteClosed;
+            }
+
+            return DisconnectReason.Error;
+        }
     }
 }

EonaCat.Connections/Helpers/AesCryptoHelpers.cs

@@ -1,105 +0,0 @@
-using System.Security.Cryptography;
-using System.Text;
-
-namespace EonaCat.Connections.Helpers
-{
-    // This file is part of the EonaCat project(s) which is released under the Apache License.
-    // See the LICENSE file or go to https://EonaCat.com/license for full license details.
-
-    public static class AesCryptoHelpers
-    {
-        private static readonly byte[] HmacInfo = Encoding.UTF8.GetBytes("EonaCat.Connections.HMAC");
-
-        public static async Task<byte[]> EncryptDataAsync(byte[] plaintext, Aes aes)
-        {
-            byte[] iv = new byte[aes.BlockSize / 8];
-            using (var rng = RandomNumberGenerator.Create())
-            {
-                rng.GetBytes(iv);
-            }
-
-            byte[] ciphertext;
-            using (var encryptor = aes.CreateEncryptor(aes.Key, iv))
-            using (var ms = new MemoryStream())
-            using (var cs = new CryptoStream(ms, encryptor, CryptoStreamMode.Write))
-            {
-                await cs.WriteAsync(plaintext, 0, plaintext.Length);
-                cs.FlushFinalBlock();
-                ciphertext = ms.ToArray();
-            }
-
-            byte[] hmacKey = DeriveHmacKey(aes.Key);
-            byte[] toAuth = iv.Concat(ciphertext).ToArray();
-            byte[] hmac;
-            using (var h = new HMACSHA256(hmacKey))
-            {
-                hmac = h.ComputeHash(toAuth);
-            }
-
-            return toAuth.Concat(hmac).ToArray();
-        }
-
-        public static async Task<byte[]> DecryptDataAsync(byte[] payload, Aes aes)
-        {
-            int ivLen = aes.BlockSize / 8;
-            int hmacLen = 32;
-
-            if (payload.Length < ivLen + hmacLen)
-            {
-                throw new CryptographicException("Payload too short");
-            }
-
-            byte[] iv = payload.Take(ivLen).ToArray();
-            byte[] ciphertext = payload.Skip(ivLen).Take(payload.Length - ivLen - hmacLen).ToArray();
-            byte[] receivedHmac = payload.Skip(payload.Length - hmacLen).ToArray();
-
-            byte[] hmacKey = DeriveHmacKey(aes.Key);
-            byte[] toAuth = iv.Concat(ciphertext).ToArray();
-            byte[] computed;
-            using (var h = new HMACSHA256(hmacKey))
-            {
-                computed = h.ComputeHash(toAuth);
-            }
-
-            if (!FixedTimeEquals(computed, receivedHmac))
-            {
-                throw new CryptographicException("HMAC validation failed: message tampered or wrong key");
-            }
-
-            byte[] plaintext;
-            using (var decryptor = aes.CreateDecryptor(aes.Key, iv))
-            using (var ms = new MemoryStream(ciphertext))
-            using (var cs = new CryptoStream(ms, decryptor, CryptoStreamMode.Read))
-            using (var result = new MemoryStream())
-            {
-                await cs.CopyToAsync(result);
-                plaintext = result.ToArray();
-            }
-
-            return plaintext;
-        }
-
-        private static byte[] DeriveHmacKey(byte[] aesKey)
-        {
-            using var h = new HMACSHA256(aesKey);
-            return h.ComputeHash(HmacInfo);
-        }
-
-        private static bool FixedTimeEquals(byte[] a, byte[] b)
-        {
-            if (a.Length != b.Length)
-            {
-                return false;
-            }
-
-            int diff = 0;
-            for (int i = 0; i < a.Length; i++)
-            {
-                diff |= a[i] ^ b[i];
-            }
-
-            return diff == 0;
-        }
-    }
-
-}

EonaCat.Connections/Helpers/AesKeyExchange.cs

@@ -1,4 +1,5 @@
 using System.Security.Cryptography;
+using System.Text;
 
 namespace EonaCat.Connections.Helpers
 {
@@ -7,72 +8,237 @@ namespace EonaCat.Connections.Helpers
 
     public static class AesKeyExchange
     {
-        private const int _saltSize = 16;
+        // 256-bit salt
-        private const int _keySize = 32;
+        private const int _saltSize = 32;
+
+        // 128-bit IV
         private const int _ivSize = 16;
-        private const int _hmacSize = 32;
-        private const int _pbkdf2Iterations = 100_000;
 
-        // Returns an AES object derived from the password and salt
+        // 256-bit AES key
-        public static async Task<Aes> ReceiveAesKeyAsync(Stream stream, string password)
+        private const int _aesKeySize = 32;
-        {
-            // Read salt
-            byte[] salt = new byte[_saltSize];
-            await stream.ReadExactlyAsync(salt, 0, _saltSize);
 
-            // Derive key
+        // 256-bit HMAC key (key confirmation)
-            byte[] key;
+        private const int _hmacKeySize = 32;
-            using (var kdf = new Rfc2898DeriveBytes(password, salt, _pbkdf2Iterations, HashAlgorithmName.SHA256))
+
+        // PBKDF2 iterations
+        private const int _iterations = 800_000;
+
+        private static readonly byte[] KeyConfirmationLabel = Encoding.UTF8.GetBytes("KEYCONFIRMATION");
+
+        public static async Task<byte[]> EncryptDataAsync(byte[] data, Aes aes)
         {
-                key = kdf.GetBytes(_keySize);
+            using (var encryptor = aes.CreateEncryptor())
+            using (var ms = new MemoryStream())
+            using (var cs = new CryptoStream(ms, encryptor, CryptoStreamMode.Write))
+            {
+                await cs.WriteAsync(data, 0, data.Length);
+                cs.FlushFinalBlock();
+                return ms.ToArray();
+            }
         }
 
-            var aes = Aes.Create();
+        public static async Task<byte[]> DecryptDataAsync(byte[] data, Aes aes)
+        {
+            using (var decryptor = aes.CreateDecryptor())
+            using (var ms = new MemoryStream(data))
+            using (var cs = new CryptoStream(ms, decryptor, CryptoStreamMode.Read))
+            using (var result = new MemoryStream())
+            {
+                await cs.CopyToAsync(result);
+                return result.ToArray();
+            }
+        }
+
+        public static async Task<Aes> SendAesKeyAsync(Stream stream, Aes aes, string password)
+        {
+            if (stream == null)
+            {
+                throw new ArgumentNullException(nameof(stream));
+            }
+
+            if (aes == null)
+            {
+                throw new ArgumentNullException(nameof(aes));
+            }
+
+            if (string.IsNullOrWhiteSpace(password))
+            {
+                throw new ArgumentException("Password/PSK required", nameof(password));
+            }
+
+            var salt = RandomBytes(_saltSize);
+            var iv = RandomBytes(_ivSize);
+
+            // Derive AES key and HMAC key (for key confirmation)
+            var keyMaterial = DeriveKey(password, salt, _aesKeySize + _hmacKeySize);
+            var aesKey = new byte[_aesKeySize];
+            var hmacKey = new byte[_hmacKeySize];
+            Buffer.BlockCopy(keyMaterial, 0, aesKey, 0, _aesKeySize);
+            Buffer.BlockCopy(keyMaterial, _aesKeySize, hmacKey, 0, _hmacKeySize);
+
+            // Compute key confirmation HMAC = HMAC(hmacKey, "KEYCONFIRM" || salt || iv)
+            byte[] keyConfirm;
+            using (var h = new HMACSHA256(hmacKey))
+            {
+                h.TransformBlock(KeyConfirmationLabel, 0, KeyConfirmationLabel.Length, null, 0);
+                h.TransformBlock(salt, 0, salt.Length, null, 0);
+                h.TransformFinalBlock(iv, 0, iv.Length);
+                keyConfirm = h.Hash;
+            }
+
+            // Send: salt, iv, keyConfirm (each length-prefixed 4-byte big-endian)
+            await WriteWithLengthAsync(stream, salt).ConfigureAwait(false);
+            await WriteWithLengthAsync(stream, iv).ConfigureAwait(false);
+            await WriteWithLengthAsync(stream, keyConfirm).ConfigureAwait(false);
+            await stream.FlushAsync().ConfigureAwait(false);
+
+            // Configure AES and return
             aes.KeySize = 256;
-            aes.BlockSize = 128;
             aes.Mode = CipherMode.CBC;
             aes.Padding = PaddingMode.PKCS7;
-            aes.Key = key;
+            aes.Key = aesKey;
+            aes.IV = iv;
 
             return aes;
         }
 
-        // Sends salt (no key) to the other side
+        public static async Task<Aes> ReceiveAesKeyAsync(Stream stream, string password)
-        public static async Task SendAesKeyAsync(Stream stream, Aes aes, string password)
         {
-            // Generate random salt
+            if (stream == null)
-            byte[] salt = new byte[_saltSize];
-            using (var rng = RandomNumberGenerator.Create())
             {
-                rng.GetBytes(salt);
+                throw new ArgumentNullException(nameof(stream));
             }
 
-            // Derive AES key
+            if (string.IsNullOrWhiteSpace(password))
-            byte[] key;
-            using (var kdf = new Rfc2898DeriveBytes(password, salt, _pbkdf2Iterations, HashAlgorithmName.SHA256))
             {
-                key = kdf.GetBytes(_keySize);
+                throw new ArgumentException("Password/PSK required", nameof(password));
-            }
-            aes.Key = key;
-
-            // Send salt only
-            await stream.WriteAsync(salt, 0, salt.Length);
-            await stream.FlushAsync();
             }
 
-        public static async Task ReadExactlyAsync(this Stream stream, byte[] buffer, int offset, int count)
+            var salt = await ReadWithLengthAsync(stream).ConfigureAwait(false);
+            var iv = await ReadWithLengthAsync(stream).ConfigureAwait(false);
+            var keyConfirm = await ReadWithLengthAsync(stream).ConfigureAwait(false);
+
+            if (salt == null || salt.Length != _saltSize)
             {
-            int read = 0;
+                throw new InvalidOperationException("Invalid salt length");
-            while (read < count)
-            {
-                int readBytes = await stream.ReadAsync(buffer, offset + read, count - read);
-                if (readBytes == 0)
-                {
-                    throw new EndOfStreamException();
             }
 
-                read += readBytes;
+            if (iv == null || iv.Length != _ivSize)
+            {
+                throw new InvalidOperationException("Invalid IV length");
             }
+
+            var keyMaterial = DeriveKey(password, salt, _aesKeySize + _hmacKeySize);
+            var aesKey = new byte[_aesKeySize];
+            var hmacKey = new byte[_hmacKeySize];
+            Buffer.BlockCopy(keyMaterial, 0, aesKey, 0, _aesKeySize);
+            Buffer.BlockCopy(keyMaterial, _aesKeySize, hmacKey, 0, _hmacKeySize);
+
+            byte[] expected;
+            using (var h = new HMACSHA256(hmacKey))
+            {
+                h.TransformBlock(KeyConfirmationLabel, 0, KeyConfirmationLabel.Length, null, 0);
+                h.TransformBlock(salt, 0, salt.Length, null, 0);
+                h.TransformFinalBlock(iv, 0, iv.Length);
+                expected = h.Hash;
+            }
+
+            if (!FixedTimeEquals(expected, keyConfirm))
+            {
+                throw new CryptographicException("Key confirmation failed - wrong password or tampered data");
+            }
+
+            var aes = Aes.Create();
+            aes.KeySize = 256;
+            aes.Mode = CipherMode.CBC;
+            aes.Padding = PaddingMode.PKCS7;
+            aes.Key = aesKey;
+            aes.IV = iv;
+
+            return aes;
+        }
+
+
+        private static async Task WriteWithLengthAsync(Stream stream, byte[] data)
+        {
+            var byteLength = BitConverter.GetBytes(data.Length);
+            if (BitConverter.IsLittleEndian)
+            {
+                Array.Reverse(byteLength);
+            }
+
+            await stream.WriteAsync(byteLength, 0, 4).ConfigureAwait(false);
+            await stream.WriteAsync(data, 0, data.Length).ConfigureAwait(false);
+        }
+
+        private static async Task<byte[]> ReadWithLengthAsync(Stream stream)
+        {
+            var bufferLength = new byte[4];
+            await ReadExactlyAsync(stream, bufferLength, 0, 4).ConfigureAwait(false);
+            if (BitConverter.IsLittleEndian)
+            {
+                Array.Reverse(bufferLength);
+            }
+
+            int length = BitConverter.ToInt32(bufferLength, 0);
+            if (length < 0 || length > 10_000_000)
+            {
+                throw new InvalidOperationException("Invalid length");
+            }
+
+            var buffer = new byte[length];
+            await ReadExactlyAsync(stream, buffer, 0, length).ConfigureAwait(false);
+            return buffer;
+        }
+
+        private static async Task ReadExactlyAsync(Stream stream, byte[] buffer, int offset, int count)
+        {
+            int total = 0;
+            while (total < count)
+            {
+                int read = await stream.ReadAsync(buffer, offset + total, count - total).ConfigureAwait(false);
+                if (read == 0)
+                {
+                    throw new EndOfStreamException("Stream ended prematurely");
+                }
+
+                total += read;
+            }
+        }
+
+        private static byte[] DeriveKey(string password, byte[] salt, int size)
+        {
+            using (var pbkdf2 = new Rfc2898DeriveBytes(password, salt, _iterations, HashAlgorithmName.SHA256))
+            {
+                return pbkdf2.GetBytes(size);
+            }
+        }
+
+        private static byte[] RandomBytes(int n)
+        {
+            var b = new byte[n];
+            using (var random = RandomNumberGenerator.Create())
+            {
+                random.GetBytes(b);
+            }
+
+            return b;
+        }
+
+        private static bool FixedTimeEquals(byte[] a, byte[] b)
+        {
+            if (a == null || b == null || a.Length != b.Length)
+            {
+                return false;
+            }
+
+            int difference = 0;
+            for (int i = 0; i < a.Length; i++)
+            {
+                difference |= a[i] ^ b[i];
+            }
+
+            return difference == 0;
         }
     }
 }

EonaCat.Connections/IClientPlugin.cs

@@ -0,0 +1,17 @@
+namespace EonaCat.Connections
+{
+    // This file is part of the EonaCat project(s) which is released under the Apache License.
+    // See the LICENSE file or go to https://EonaCat.com/license for full license details.
+
+    public interface IClientPlugin
+    {
+        string Name { get; }
+
+        void OnClientStarted(NetworkClient client);
+        void OnClientConnected(NetworkClient client);
+        void OnClientDisconnected(NetworkClient client, DisconnectReason reason, Exception exception);
+        void OnDataReceived(NetworkClient client, byte[] data, string stringData, bool isBinary);
+        void OnError(NetworkClient client, Exception exception, string message);
+        void OnClientStopped(NetworkClient client);
+    }
+}

EonaCat.Connections/IServerPlugin.cs

@@ -0,0 +1,55 @@
+using EonaCat.Connections.Models;
+
+namespace EonaCat.Connections
+{
+    // This file is part of the EonaCat project(s) which is released under the Apache License.
+    // See the LICENSE file or go to https://EonaCat.com/license for full license details.
+
+    /// <summary>
+    /// Defines the contract for plugins that extend the behavior of the NetworkServer.
+    /// Implement this interface to hook into server events such as
+    /// client connections, disconnections, message handling, and lifecycle events.
+    /// </summary>
+    public interface IServerPlugin
+    {
+        /// <summary>
+        /// Gets the unique name of this plugin (used for logging/error reporting).
+        /// </summary>
+        string Name { get; }
+
+        /// <summary>
+        /// Called when the server has started successfully.
+        /// </summary>
+        /// <param name="server">The server instance that started.</param>
+        void OnServerStarted(NetworkServer server);
+
+        /// <summary>
+        /// Called when the server has stopped.
+        /// </summary>
+        /// <param name="server">The server instance that stopped.</param>
+        void OnServerStopped(NetworkServer server);
+
+        /// <summary>
+        /// Called when a client successfully connects.
+        /// </summary>
+        /// <param name="client">The connected client.</param>
+        void OnClientConnected(Connection client);
+
+        /// <summary>
+        /// Called when a client disconnects.
+        /// </summary>
+        /// <param name="client">The client that disconnected.</param>
+        /// <param name="reason">The reason for disconnection.</param>
+        /// <param name="exception">Optional exception if the disconnect was caused by an error.</param>
+        void OnClientDisconnected(Connection client, DisconnectReason reason, Exception exception);
+
+        /// <summary>
+        /// Called when data is received from a client.
+        /// </summary>
+        /// <param name="client">The client that sent the data.</param>
+        /// <param name="data">The raw bytes received.</param>
+        /// <param name="stringData">The decoded string (if text-based, otherwise null).</param>
+        /// <param name="isBinary">True if the message is binary data, false if text.</param>
+        void OnDataReceived(Connection client, byte[] data, string stringData, bool isBinary);
+    }
+}

EonaCat.Connections/Models/Connection.cs

@@ -40,14 +40,26 @@ namespace EonaCat.Connections.Models
             }
         }
 
+        public bool HasNickname => !string.IsNullOrWhiteSpace(_nickName) && _nickName != Id;
+
         public DateTime ConnectedAt { get; set; }
         public DateTime LastActive { get; set; }
         public bool IsSecure { get; set; }
         public bool IsEncrypted { get; set; }
         public Aes AesEncryption { get; set; }
         public CancellationTokenSource CancellationToken { get; set; }
-        public long BytesSent { get; set; }
+        private long _bytesReceived;
-        public long BytesReceived { get; set; }
+        private long _bytesSent;
-        public SemaphoreSlim SendLock { get; internal set; }
+        public long BytesReceived => Interlocked.Read(ref _bytesReceived);
+        public long BytesSent => Interlocked.Read(ref _bytesSent);
+
+        public void AddBytesReceived(long count) => Interlocked.Add(ref _bytesReceived, count);
+        public void AddBytesSent(long count) => Interlocked.Add(ref _bytesSent, count);
+
+        public SemaphoreSlim SendLock { get; } = new SemaphoreSlim(1, 1);
+        public SemaphoreSlim ReadLock { get; } = new SemaphoreSlim(1, 1);
+
+        private int _disconnected;
+        public bool MarkDisconnected() => Interlocked.Exchange(ref _disconnected, 1) == 0;
     }
 }

EonaCat.Connections/NetworkClient.cs

@@ -11,6 +11,9 @@ using ErrorEventArgs = EonaCat.Connections.EventArguments.ErrorEventArgs;
 
 namespace EonaCat.Connections
 {
+    // This file is part of the EonaCat project(s) which is released under the Apache License.
+    // See the LICENSE file or go to https://EonaCat.com/license for full license details.
+
     public class NetworkClient : IDisposable
     {
         private readonly Configuration _config;
@@ -21,27 +24,20 @@ namespace EonaCat.Connections
         private CancellationTokenSource _cancellation;
         private bool _isConnected;
 
-        private readonly object _stateLock = new object();
+        public bool IsConnected => _isConnected;
-        private readonly SemaphoreSlim _sendLock = new SemaphoreSlim(1, 1);
+        public bool IsSecure => _config != null && (_config.UseSsl || _config.UseAesEncryption);
+        public bool IsEncrypted => _config != null && _config.UseAesEncryption;
+        public bool IsTcp => _config != null && _config.Protocol == ProtocolType.TCP;
 
-        private readonly HashSet<string> _joinedRooms = new();
+        private readonly SemaphoreSlim _sendLock = new(1, 1);
+        private readonly SemaphoreSlim _connectLock = new(1, 1);
+        private readonly SemaphoreSlim _readLock = new(1, 1);
 
-        public bool IsConnected
+        public DateTime ConnectionTime { get; private set; }
-        {
+        public DateTime StartTime { get; set; }
-            get { lock (_stateLock)
+        public TimeSpan Uptime => DateTime.UtcNow - ConnectionTime;
-                {
-                    return _isConnected;
-                }
-            }
-            private set { lock (_stateLock)
-                {
-                    _isConnected = value;
-                }
-            }
-        }
-
-        public bool IsAutoReconnecting { get; private set; }
 
+        private bool _disposed;
         public event EventHandler<ConnectionEventArgs> OnConnected;
         public event EventHandler<DataReceivedEventArgs> OnDataReceived;
         public event EventHandler<ConnectionEventArgs> OnDisconnected;
@@ -49,18 +45,19 @@ namespace EonaCat.Connections
         public event EventHandler<ErrorEventArgs> OnEncryptionError;
         public event EventHandler<ErrorEventArgs> OnGeneralError;
 
-        public string IpAddress => _config?.Host ?? string.Empty;
+        private readonly List<IClientPlugin> _plugins = new();
-        public int Port => _config?.Port ?? 0;
 
-        public NetworkClient(Configuration config) => _config = config;
+        public NetworkClient(Configuration config)
+        {
+            _config = config ?? throw new ArgumentNullException(nameof(config));
+        }
 
         public async Task ConnectAsync()
         {
-            lock (_stateLock)
+            await _connectLock.WaitAsync();
+            try
             {
-                _cancellation?.Cancel();
                 _cancellation = new CancellationTokenSource();
-            }
 
                 if (_config.Protocol == ProtocolType.TCP)
                 {
@@ -71,30 +68,46 @@ namespace EonaCat.Connections
                     await ConnectUdpAsync();
                 }
             }
+            catch (Exception ex)
+            {
+                OnGeneralError?.Invoke(this, new ErrorEventArgs { Exception = ex, Message = "Connection error" });
+                NotifyError(ex, "General error");
+                if (_config.EnableAutoReconnect)
+                {
+                    _ = Task.Run(() => AutoReconnectAsync());
+                }
+            }
+            finally
+            {
+                _connectLock.Release();
+            }
+        }
 
         private async Task ConnectTcpAsync()
         {
-            try
+            _tcpClient = new TcpClient();
-            {
+            await _tcpClient.ConnectAsync(_config.Host, _config.Port);
-                var client = new TcpClient();
-                await client.ConnectAsync(_config.Host, _config.Port);
 
-                Stream stream = client.GetStream();
+            Stream stream = _tcpClient.GetStream();
 
+            // Setup SSL if required
             if (_config.UseSsl)
             {
                 try
                 {
-                        var sslStream = new SslStream(stream, false, _config.GetRemoteCertificateValidationCallback());
+                    var sslStream = new SslStream(stream, false, userCertificateValidationCallback: _config.GetRemoteCertificateValidationCallback());
                     if (_config.Certificate != null)
                     {
-                            sslStream.AuthenticateAsClient(_config.Host, new X509CertificateCollection { _config.Certificate }, _config.CheckCertificateRevocation);
+                        await sslStream.AuthenticateAsClientAsync(
+                            _config.Host,
+                            new X509CertificateCollection { _config.Certificate },
+                            _config.CheckCertificateRevocation
+                        );
                     }
                     else
                     {
-                            sslStream.AuthenticateAsClient(_config.Host);
+                        await sslStream.AuthenticateAsClientAsync(_config.Host);
                     }
-
                     stream = sslStream;
                 }
                 catch (Exception ex)
@@ -104,6 +117,7 @@ namespace EonaCat.Connections
                 }
             }
 
+            // Setup AES encryption if required
             if (_config.UseAesEncryption)
             {
                 try
@@ -117,52 +131,86 @@ namespace EonaCat.Connections
                 }
             }
 
-                lock (_stateLock)
-                {
-                    _tcpClient = client;
             _stream = stream;
-                    IsConnected = true;
+            _isConnected = true;
-                }
+            ConnectionTime = DateTime.UtcNow;
-
             OnConnected?.Invoke(this, new ConnectionEventArgs { ClientId = "self", RemoteEndPoint = new IPEndPoint(IPAddress.Parse(_config.Host), _config.Port) });
+            NotifyConnected();
 
-                _ = Task.Run(() => ReceiveDataAsync(_cancellation.Token), _cancellation.Token);
+            // Start receiving data
+            _ = Task.Run(() => ReceiveDataAsync(), _cancellation.Token);
         }
-            catch (Exception ex)
+
+        public void RegisterPlugin(IClientPlugin plugin)
         {
-                IsConnected = false;
+            if (_plugins.Any(p => p.Name == plugin.Name))
-                OnGeneralError?.Invoke(this, new ErrorEventArgs { Exception = ex, Message = "Failed to connect" });
+                return;
-                _ = Task.Run(() => AutoReconnectAsync());
+
+            _plugins.Add(plugin);
+            plugin.OnClientStarted(this);
+        }
+
+        public void UnregisterPlugin(IClientPlugin plugin)
+        {
+            if (_plugins.Remove(plugin))
+            {
+                plugin.OnClientStopped(this);
             }
         }
 
+        private void NotifyConnected()
+        {
+            foreach (var plugin in _plugins)
+            {
+                plugin.OnClientConnected(this);
+            }
+        }
+
+        private void NotifyDisconnected(DisconnectReason reason, Exception exception)
+        {
+            foreach (var plugin in _plugins)
+            {
+                plugin.OnClientDisconnected(this, reason, exception);
+            }
+        }
+
+        private void NotifyData(byte[] data, string stringData, bool isBinary)
+        {
+            foreach (var plugin in _plugins)
+            {
+                plugin.OnDataReceived(this, data, stringData, isBinary);
+            }
+        }
+
+        private void NotifyError(Exception ex, string message)
+        {
+            foreach (var plugin in _plugins)
+            {
+                plugin.OnError(this, ex, message);
+            }
+        }
+
+        public string IpAddress => _config != null ? _config.Host : string.Empty;
+        public int Port => _config != null ? _config.Port : 0;
+
+        public bool IsAutoReconnectRunning { get; private set; }
+
         private async Task ConnectUdpAsync()
         {
-            try
+            _udpClient = new UdpClient();
-            {
+            _udpClient.Connect(_config.Host, _config.Port);
-                var client = new UdpClient();
+            _isConnected = true;
-                client.Connect(_config.Host, _config.Port);
+            ConnectionTime = DateTime.UtcNow;
-
-                lock (_stateLock)
-                {
-                    _udpClient = client;
-                    IsConnected = true;
-                }
-
             OnConnected?.Invoke(this, new ConnectionEventArgs { ClientId = "self", RemoteEndPoint = new IPEndPoint(IPAddress.Parse(_config.Host), _config.Port) });
 
-                _ = Task.Run(() => ReceiveUdpDataAsync(_cancellation.Token), _cancellation.Token);
+            // Start receiving data
-            }
+            _ = Task.Run(() => ReceiveUdpDataAsync(), _cancellation.Token);
-            catch (Exception ex)
+            await Task.CompletedTask;
-            {
-                IsConnected = false;
-                OnGeneralError?.Invoke(this, new ErrorEventArgs { Exception = ex, Message = "Failed to connect UDP" });
-            }
         }
 
-        private async Task ReceiveDataAsync(CancellationToken ct)
+        private async Task ReceiveDataAsync()
         {
-            while (!ct.IsCancellationRequested && IsConnected)
+            while (!_cancellation.Token.IsCancellationRequested && _isConnected)
             {
                 try
                 {
@@ -171,7 +219,8 @@ namespace EonaCat.Connections
                     if (_config.UseAesEncryption && _aesEncryption != null)
                     {
                         var lengthBuffer = new byte[4];
-                        if (await ReadExactAsync(_stream, lengthBuffer, 4, ct) == 0)
+                        int read = await ReadExactAsync(_stream, lengthBuffer, 4, _cancellation.Token).ConfigureAwait(false);
+                        if (read == 0)
                         {
                             break;
                         }
@@ -182,19 +231,33 @@ namespace EonaCat.Connections
                         }
 
                         int length = BitConverter.ToInt32(lengthBuffer, 0);
+                        if (length <= 0)
+                        {
+                            throw new InvalidDataException("Invalid packet length");
+                        }
 
                         var encrypted = new byte[length];
-                        await ReadExactAsync(_stream, encrypted, length, ct);
+                        await ReadExactAsync(_stream, encrypted, length, _cancellation.Token).ConfigureAwait(false);
-
+                        data = await AesKeyExchange.DecryptDataAsync(encrypted, _aesEncryption).ConfigureAwait(false);
-                        data = await AesCryptoHelpers.DecryptDataAsync(encrypted, _aesEncryption);
                     }
                     else
                     {
                         data = new byte[_config.BufferSize];
-                        int bytesRead = await _stream.ReadAsync(data, 0, data.Length, ct);
+                        int bytesRead;
+                        await _readLock.WaitAsync(_cancellation.Token);
+                        try
+                        {
+                            bytesRead = await _stream.ReadAsync(data, 0, data.Length, _cancellation.Token);
+                        }
+                        finally
+                        {
+                            _readLock.Release();
+                        }
+
                         if (bytesRead == 0)
                         {
-                            break;
+                            await DisconnectAsync(DisconnectReason.RemoteClosed);
+                            return;
                         }
 
                         if (bytesRead < data.Length)
@@ -207,12 +270,21 @@ namespace EonaCat.Connections
 
                     await ProcessReceivedDataAsync(data);
                 }
+                catch (IOException ioEx)
+                {
+                    await DisconnectAsync(DisconnectReason.RemoteClosed, ioEx);
+                }
+                catch (SocketException sockEx)
+                {
+                    await DisconnectAsync(DisconnectReason.Error, sockEx);
+                }
+                catch (OperationCanceledException)
+                {
+                    await DisconnectAsync(DisconnectReason.Timeout);
+                }
                 catch (Exception ex)
                 {
-                    IsConnected = false;
+                    await DisconnectAsync(DisconnectReason.Error, ex);
-                    OnGeneralError?.Invoke(this, new ErrorEventArgs { Exception = ex, Message = "Error receiving data" });
-                    _ = Task.Run(() => AutoReconnectAsync());
-                    break;
                 }
             }
 
@@ -222,6 +294,9 @@ namespace EonaCat.Connections
         private async Task<int> ReadExactAsync(Stream stream, byte[] buffer, int length, CancellationToken ct)
         {
             int offset = 0;
+            await _readLock.WaitAsync(ct);
+            try
+            {
                 while (offset < length)
                 {
                     int read = await stream.ReadAsync(buffer, offset, length - offset, ct);
@@ -229,15 +304,19 @@ namespace EonaCat.Connections
                     {
                         return 0;
                     }
-
                     offset += read;
                 }
                 return offset;
             }
-
+            finally
-        private async Task ReceiveUdpDataAsync(CancellationToken ct)
             {
-            while (!ct.IsCancellationRequested && IsConnected)
+                _readLock.Release();
+            }
+        }
+
+        private async Task ReceiveUdpDataAsync()
+        {
+            while (!_cancellation.Token.IsCancellationRequested && _isConnected)
             {
                 try
                 {
@@ -246,8 +325,10 @@ namespace EonaCat.Connections
                 }
                 catch (Exception ex)
                 {
-                    OnGeneralError?.Invoke(this, new ErrorEventArgs { Exception = ex, Message = "Error receiving UDP data" });
+                    OnGeneralError?.Invoke(this, new ErrorEventArgs { Exception = ex, Message = "Error receiving data" });
-                    IsConnected = false;
+                    NotifyError(ex, "General error");
+                    _isConnected = false;
+                    ConnectionTime = DateTime.MinValue;
                     _ = Task.Run(() => AutoReconnectAsync());
                     break;
                 }
@@ -258,15 +339,27 @@ namespace EonaCat.Connections
         {
             try
             {
-                string stringData = null;
                 bool isBinary = true;
+                string stringData = null;
 
                 try
                 {
                     stringData = Encoding.UTF8.GetString(data);
-                    isBinary = Encoding.UTF8.GetBytes(stringData).Length != data.Length;
+                    if (Encoding.UTF8.GetBytes(stringData).Length == data.Length)
+                    {
+                        isBinary = false;
+                    }
+                }
+                catch
+                {
+                    // Keep as binary
+                }
+
+                if (!isBinary && stringData != null && stringData.Equals("DISCONNECT", StringComparison.OrdinalIgnoreCase))
+                {
+                    await DisconnectAsync(DisconnectReason.RemoteClosed);
+                    return;
                 }
-                catch { }
 
                 OnDataReceived?.Invoke(this, new DataReceivedEventArgs
                 {
@@ -275,17 +368,25 @@ namespace EonaCat.Connections
                     StringData = stringData,
                     IsBinary = isBinary
                 });
+                NotifyData(data, stringData, isBinary);
             }
             catch (Exception ex)
             {
-                var handler = _config.UseAesEncryption ? OnEncryptionError : OnGeneralError;
+                if (_config.UseAesEncryption)
-                handler?.Invoke(this, new ErrorEventArgs { Exception = ex, Message = "Error processing data" });
+                {
+                    OnEncryptionError?.Invoke(this, new ErrorEventArgs { Exception = ex, Message = "Error processing data" });
+                }
+                else
+                {
+                    OnGeneralError?.Invoke(this, new ErrorEventArgs { Exception = ex, Message = "Error processing data" });
+                    NotifyError(ex, "General error");
+                }
             }
         }
 
         public async Task SendAsync(byte[] data)
         {
-            if (!IsConnected)
+            if (!_isConnected)
             {
                 return;
             }
@@ -295,7 +396,7 @@ namespace EonaCat.Connections
             {
                 if (_config.UseAesEncryption && _aesEncryption != null)
                 {
-                    data = await AesCryptoHelpers.EncryptDataAsync(data, _aesEncryption);
+                    data = await AesKeyExchange.EncryptDataAsync(data, _aesEncryption);
 
                     var lengthPrefix = BitConverter.GetBytes(data.Length);
                     if (BitConverter.IsLittleEndian)
@@ -321,8 +422,15 @@ namespace EonaCat.Connections
             }
             catch (Exception ex)
             {
-                var handler = _config.UseAesEncryption ? OnEncryptionError : OnGeneralError;
+                if (_config.UseAesEncryption)
-                handler?.Invoke(this, new ErrorEventArgs { Exception = ex, Message = "Error sending data" });
+                {
+                    OnEncryptionError?.Invoke(this, new ErrorEventArgs { Exception = ex, Message = "Error encrypting/sending data" });
+                }
+                else
+                {
+                    OnGeneralError?.Invoke(this, new ErrorEventArgs { Exception = ex, Message = "Error sending data" });
+                    NotifyError(ex, "General error");
+                }
             }
             finally
             {
@@ -330,121 +438,140 @@ namespace EonaCat.Connections
             }
         }
 
-        /// <summary>Join a room (server should recognize this command)</summary>
+        public async Task SendAsync(string message)
-        public async Task JoinRoomAsync(string roomName)
         {
-            if (string.IsNullOrWhiteSpace(roomName) || _joinedRooms.Contains(roomName))
+            await SendAsync(Encoding.UTF8.GetBytes(message));
-            {
-                return;
         }
 
-            _joinedRooms.Add(roomName);
+        public async Task SendNicknameAsync(string nickname)
-            await SendAsync($"JOIN_ROOM:{roomName}");
-        }
-
-        public async Task LeaveRoomAsync(string roomName)
         {
-            if (string.IsNullOrWhiteSpace(roomName) || !_joinedRooms.Contains(roomName))
+            await SendAsync($"NICKNAME:{nickname}");
-            {
-                return;
         }
 
-            _joinedRooms.Remove(roomName);
-            await SendAsync($"LEAVE_ROOM:{roomName}");
-        }
-
-        public async Task SendToRoomAsync(string roomName, string message)
-        {
-            if (string.IsNullOrWhiteSpace(roomName) || !_joinedRooms.Contains(roomName))
-            {
-                return;
-            }
-
-            await SendAsync($"ROOM_MSG:{roomName}:{message}");
-        }
-
-        public IReadOnlyCollection<string> GetJoinedRooms()
-        {
-            return _joinedRooms.ToList().AsReadOnly();
-        }
-
-        public async Task SendAsync(string message) => await SendAsync(Encoding.UTF8.GetBytes(message));
-        private async Task SendNicknameAsync(string nickname) => await SendAsync($"NICKNAME:{nickname}");
-
         private async Task AutoReconnectAsync()
         {
-            if (!_config.EnableAutoReconnect || IsAutoReconnecting)
+            if (!_config.EnableAutoReconnect)
+            {
+                return;
+            }
+
+            if (IsAutoReconnectRunning)
             {
                 return;
             }
 
             int attempt = 0;
-            IsAutoReconnecting = true;
 
-            while (!IsConnected && (_config.MaxReconnectAttempts == 0 || attempt < _config.MaxReconnectAttempts))
+            while (_config.EnableAutoReconnect && !_isConnected && (_config.MaxReconnectAttempts == 0 || attempt < _config.MaxReconnectAttempts))
             {
                 attempt++;
+
                 try
                 {
-                    OnGeneralError?.Invoke(this, new ErrorEventArgs { Message = $"Reconnecting attempt {attempt}" });
+                    OnGeneralError?.Invoke(this, new ErrorEventArgs { Message = $"Attempting to reconnect (Attempt {attempt})" });
+                    IsAutoReconnectRunning = true;
                     await ConnectAsync();
-                    if (IsConnected)
+
+                    if (_isConnected)
                     {
-                        OnGeneralError?.Invoke(this, new ErrorEventArgs { Message = $"Reconnected after {attempt} attempt(s)" });
+                        OnGeneralError?.Invoke(this, new ErrorEventArgs { Message = $"Reconnected successfully after {attempt} attempt(s)" });
+                        IsAutoReconnectRunning = false;
                         break;
                     }
                 }
-                catch { }
+                catch
+                {
+                    // Do nothing
+                }
 
                 await Task.Delay(_config.ReconnectDelayMs);
             }
 
-            if (!IsConnected)
+            if (!_isConnected)
             {
                 OnGeneralError?.Invoke(this, new ErrorEventArgs { Message = "Failed to reconnect" });
             }
-
-            IsAutoReconnecting = false;
         }
 
-        private string _nickname;
+        public async Task DisconnectAsync(
-        public async Task SetNicknameAsync(string nickname)
+    DisconnectReason reason = DisconnectReason.LocalClosed,
+    Exception exception = null,
+    bool forceDisconnection = false)
         {
-            _nickname = nickname;
+            await _connectLock.WaitAsync();
-            await SendNicknameAsync(nickname);
+            try
-        }
-
-        public string Nickname => _nickname;
-
-
-        public async Task DisconnectAsync()
             {
-            lock (_stateLock)
+                if (!_isConnected)
-            {
-                if (!IsConnected)
                 {
                     return;
                 }
 
-                IsConnected = false;
+                _isConnected = false;
-                _cancellation?.Cancel();
+                ConnectionTime = DateTime.MinValue;
-            }
 
+                _cancellation?.Cancel();
                 _tcpClient?.Close();
                 _udpClient?.Close();
                 _stream?.Dispose();
                 _aesEncryption?.Dispose();
-            _joinedRooms?.Clear();
 
-            OnDisconnected?.Invoke(this, new ConnectionEventArgs { ClientId = "self" });
+                OnDisconnected?.Invoke(this, new ConnectionEventArgs
+                {
+                    ClientId = "self",
+                    RemoteEndPoint = new IPEndPoint(IPAddress.Parse(_config.Host), _config.Port),
+                    Reason = ConnectionEventArgs.Determine(reason, exception),
+                    Exception = exception
+                });
+                NotifyDisconnected(reason, exception);
+
+                if (!forceDisconnection && reason != DisconnectReason.Forced)
+                {
+                    _ = Task.Run(() => AutoReconnectAsync());
+                }
+                else
+                {
+                    Console.WriteLine("Auto-reconnect disabled due to forced disconnection.");
+                    _config.EnableAutoReconnect = false;
+                }
+            }
+            finally
+            {
+                _connectLock.Release();
+            }
+        }
+
+
+        public async ValueTask DisposeAsync()
+        {
+            if (_disposed)
+            {
+                return;
+            }
+
+            _disposed = true;
+
+            await DisconnectAsync(forceDisconnection: true);
+
+            foreach (var plugin in _plugins.ToList())
+            {
+                plugin.OnClientStopped(this);
+            }
+
+            _cancellation?.Dispose();
+            _sendLock.Dispose();
+            _connectLock.Dispose();
+            _readLock.Dispose();
         }
 
         public void Dispose()
         {
-            _cancellation?.Cancel();
+            if (_disposed)
-            DisconnectAsync().Wait();
+            {
-            _cancellation?.Dispose();
+                return;
-            _sendLock.Dispose();
+            }
+
+            _disposed = true;
+            DisposeAsync().AsTask().GetAwaiter().GetResult();
         }
     }
 }

EonaCat.Connections/Plugins/Client/ClientHttpMetricsPlugin.cs

@@ -0,0 +1,112 @@
+using EonaCat.Json;
+using System.Net;
+
+namespace EonaCat.Connections.Plugins.Client
+{
+    // This file is part of the EonaCat project(s) which is released under the Apache License.
+    // See the LICENSE file or go to https://EonaCat.com/license for full license details.
+
+    public class ClientHttpMetricsPlugin : IClientPlugin
+    {
+        public string Name => "ClientMetricsPlugin";
+
+        private NetworkClient _client;
+        private long _bytesSent;
+        private long _bytesReceived;
+        private long _messagesSent;
+        private long _messagesReceived;
+
+        private readonly int _httpPort;
+        private HttpListener _httpListener;
+        private CancellationTokenSource _cts;
+
+        public ClientHttpMetricsPlugin(int httpPort = 8080)
+        {
+            _httpPort = httpPort;
+        }
+
+        public void OnClientStarted(NetworkClient client)
+        {
+            _client = client;
+            _cts = new CancellationTokenSource();
+            StartHttpServer(_cts.Token);
+        }
+
+        public void OnClientConnected(NetworkClient client)
+        {
+            Console.WriteLine($"[{Name}] Connected to server at {client.IpAddress}:{client.Port}");
+        }
+
+        public void OnClientDisconnected(NetworkClient client, DisconnectReason reason, Exception exception)
+        {
+            Console.WriteLine($"[{Name}] Disconnected: {reason} {exception?.Message}");
+        }
+
+        public void OnDataReceived(NetworkClient client, byte[] data, string stringData, bool isBinary)
+        {
+            _bytesReceived += data.Length;
+            _messagesReceived++;
+        }
+
+        public void OnError(NetworkClient client, Exception exception, string message)
+        {
+            Console.WriteLine($"[{Name}] Error: {message} - {exception?.Message}");
+        }
+
+        public void OnClientStopped(NetworkClient client)
+        {
+            _cts.Cancel();
+            _httpListener?.Stop();
+            Console.WriteLine($"[{Name}] Plugin stopped.");
+        }
+
+        public void IncrementSent(byte[] data)
+        {
+            _bytesSent += data.Length;
+            _messagesSent++;
+        }
+
+        private void StartHttpServer(CancellationToken token)
+        {
+            _httpListener = new HttpListener();
+            _httpListener.Prefixes.Add($"http://*:{_httpPort}/metrics/");
+            _httpListener.Start();
+
+            Task.Run(async () =>
+            {
+                while (!token.IsCancellationRequested)
+                {
+                    try
+                    {
+                        var context = await _httpListener.GetContextAsync();
+                        var response = context.Response;
+
+                        var metrics = new
+                        {
+                            IsConnected = _client.IsConnected,
+                            Ip = _client.IpAddress,
+                            Port = _client.Port,
+                            Uptime = _client.Uptime.TotalSeconds,
+                            BytesSent = _bytesSent,
+                            BytesReceived = _bytesReceived,
+                            MessagesSent = _messagesSent,
+                            MessagesReceived = _messagesReceived
+                        };
+
+                        var json = JsonHelper.ToJson(metrics, Formatting.Indented);
+                        var buffer = System.Text.Encoding.UTF8.GetBytes(json);
+
+                        response.ContentType = "application/json";
+                        response.ContentLength64 = buffer.Length;
+                        await response.OutputStream.WriteAsync(buffer, 0, buffer.Length, token);
+                        response.Close();
+                    }
+                    catch (Exception)
+                    {
+                        // ignore
+                    }
+                }
+            }, token);
+        }
+    }
+}

EonaCat.Connections/Plugins/Server/HttpMetricsPlugin.cs

@@ -0,0 +1,106 @@
+using EonaCat.Connections.Models;
+using EonaCat.Json;
+using System.Net;
+using System.Text;
+
+namespace EonaCat.Connections.Plugins.Server
+{
+    // This file is part of the EonaCat project(s) which is released under the Apache License.
+    // See the LICENSE file or go to https://EonaCat.com/license for full license details.
+
+    public class HttpMetricsPlugin : IServerPlugin
+    {
+        public string Name => "HttpMetricsPlugin";
+
+        private readonly int _port;
+        private HttpListener _httpListener;
+        private CancellationTokenSource _cts;
+        private NetworkServer _server;
+
+        public HttpMetricsPlugin(int port = 9100)
+        {
+            _port = port;
+        }
+
+        public void OnServerStarted(NetworkServer server)
+        {
+            _server = server;
+            _cts = new CancellationTokenSource();
+            _httpListener = new HttpListener();
+            _httpListener.Prefixes.Add($"http://*:{_port}/metrics/");
+
+            try
+            {
+                _httpListener.Start();
+                Console.WriteLine($"[{Name}] Metrics endpoint running at http://localhost:{_port}/metrics/");
+            }
+            catch (HttpListenerException ex)
+            {
+                Console.WriteLine($"[{Name}] Failed to start HTTP listener: {ex.Message}");
+                return;
+            }
+
+            Task.Run(async () =>
+            {
+                while (!_cts.IsCancellationRequested)
+                {
+                    try
+                    {
+                        var context = await _httpListener.GetContextAsync();
+
+                        if (context.Request.Url.AbsolutePath == "/metrics")
+                        {
+                            var stats = _server.GetStats();
+
+                            var responseObj = new
+                            {
+                                uptime = stats.Uptime.ToString(),
+                                startTime = stats.StartTime,
+                                activeConnections = stats.ActiveConnections,
+                                totalConnections = stats.TotalConnections,
+                                bytesSent = stats.BytesSent,
+                                bytesReceived = stats.BytesReceived,
+                                messagesSent = stats.MessagesSent,
+                                messagesReceived = stats.MessagesReceived,
+                                messagesPerSecond = stats.MessagesPerSecond
+                            };
+
+                            var json = JsonHelper.ToJson(responseObj, Formatting.Indented);
+                            var buffer = Encoding.UTF8.GetBytes(json);
+
+                            context.Response.ContentType = "application/json";
+                            context.Response.StatusCode = 200;
+                            await context.Response.OutputStream.WriteAsync(buffer, 0, buffer.Length);
+                            context.Response.OutputStream.Close();
+                        }
+                        else
+                        {
+                            context.Response.StatusCode = 404;
+                            context.Response.Close();
+                        }
+                    }
+                    catch (ObjectDisposedException) { }
+                    catch (HttpListenerException) { }
+                    catch (Exception ex)
+                    {
+                        Console.WriteLine($"[{Name}] Error: {ex}");
+                    }
+                }
+            }, _cts.Token);
+        }
+
+        public void OnServerStopped(NetworkServer server)
+        {
+            _cts?.Cancel();
+            if (_httpListener != null && _httpListener.IsListening)
+            {
+                _httpListener.Stop();
+                _httpListener.Close();
+            }
+        }
+
+        public void OnClientConnected(Connection client) { }
+        public void OnClientDisconnected(Connection client, DisconnectReason reason, Exception exception) { }
+        public void OnDataReceived(Connection client, byte[] data, string stringData, bool isBinary) { }
+    }
+}

EonaCat.Connections/Plugins/Server/IdleTimeoutPlugin.cs

@@ -0,0 +1,53 @@
+using EonaCat.Connections.Models;
+
+namespace EonaCat.Connections.Plugins.Server
+{
+    // This file is part of the EonaCat project(s) which is released under the Apache License.
+    // See the LICENSE file or go to https://EonaCat.com/license for full license details.
+
+    public class IdleTimeoutPlugin : IServerPlugin
+    {
+        public string Name => "IdleTimeoutPlugin";
+
+        private readonly TimeSpan _timeout;
+        private CancellationTokenSource _cts;
+
+        public IdleTimeoutPlugin(TimeSpan timeout)
+        {
+            _timeout = timeout;
+        }
+
+        public void OnServerStarted(NetworkServer server)
+        {
+            _cts = new CancellationTokenSource();
+
+            // Background task to check idle clients
+            Task.Run(async () =>
+            {
+                while (!_cts.IsCancellationRequested)
+                {
+                    foreach (var kvp in server.GetClients())
+                    {
+                        var client = kvp.Value;
+                        if (DateTime.UtcNow - client.LastActive > _timeout)
+                        {
+                            Console.WriteLine($"[{Name}] Disconnecting idle client {client.RemoteEndPoint}");
+                            _ = server.DisconnectClientAsync(client.Id, DisconnectReason.Timeout);
+                        }
+                    }
+
+                    await Task.Delay(5000, _cts.Token); // Check every 5s
+                }
+            }, _cts.Token);
+        }
+
+        public void OnServerStopped(NetworkServer server)
+        {
+            _cts?.Cancel();
+        }
+
+        public void OnClientConnected(Connection client) { }
+        public void OnClientDisconnected(Connection client, DisconnectReason reason, Exception exception) { }
+        public void OnDataReceived(Connection client, byte[] data, string stringData, bool isBinary) { }
+    }
+}

EonaCat.Connections/Plugins/Server/MetricsPlugin.cs

@@ -0,0 +1,65 @@
+using EonaCat.Connections.Models;
+
+namespace EonaCat.Connections.Plugins.Server
+{
+    // This file is part of the EonaCat project(s) which is released under the Apache License.
+    // See the LICENSE file or go to https://EonaCat.com/license for full license details.
+
+    public class MetricsPlugin : IServerPlugin
+    {
+        public string Name => "MetricsPlugin";
+
+        private readonly TimeSpan _interval;
+        private CancellationTokenSource _cts;
+        private NetworkServer _server;
+
+        public MetricsPlugin(TimeSpan interval)
+        {
+            _interval = interval;
+        }
+
+        public void OnServerStarted(NetworkServer server)
+        {
+            _server = server;
+            _cts = new CancellationTokenSource();
+
+            Task.Run(async () =>
+            {
+                while (!_cts.IsCancellationRequested)
+                {
+                    try
+                    {
+                        var stats = server.GetStats();
+
+                        Console.WriteLine(
+                            $"[{Name}] Uptime: {stats.Uptime:g} | " +
+                            $"Active: {stats.ActiveConnections} | " +
+                            $"Total: {stats.TotalConnections} | " +
+                            $"Msgs In: {stats.MessagesReceived} | " +
+                            $"Msgs Out: {stats.MessagesSent} | " +
+                            $"Bytes In: {stats.BytesReceived} | " +
+                            $"Bytes Out: {stats.BytesSent} | " +
+                            $"Msg/s: {stats.MessagesPerSecond:F2}"
+                        );
+
+                        await Task.Delay(_interval, _cts.Token);
+                    }
+                    catch (TaskCanceledException) { }
+                    catch (Exception ex)
+                    {
+                        Console.WriteLine($"[{Name}] Error logging metrics: {ex}");
+                    }
+                }
+            }, _cts.Token);
+        }
+
+        public void OnServerStopped(NetworkServer server)
+        {
+            _cts?.Cancel();
+        }
+
+        public void OnClientConnected(Connection client) { }
+        public void OnClientDisconnected(Connection client, DisconnectReason reason, Exception exception) { }
+        public void OnDataReceived(Connection client, byte[] data, string stringData, bool isBinary) { }
+    }
+}

EonaCat.Connections/Plugins/Server/RateLimiterPlugin.cs

@@ -0,0 +1,57 @@
+using EonaCat.Connections.Models;
+using System.Collections.Concurrent;
+
+namespace EonaCat.Connections.Plugins.Server
+{
+    // This file is part of the EonaCat project(s) which is released under the Apache License.
+    // See the LICENSE file or go to https://EonaCat.com/license for full license details.
+
+    public class RateLimiterPlugin : IServerPlugin
+    {
+        public string Name => "RateLimiterPlugin";
+
+        private readonly int _maxMessages;
+        private readonly TimeSpan _interval;
+        private readonly ConcurrentDictionary<string, ConcurrentQueue<DateTime>> _messageTimestamps;
+
+        public RateLimiterPlugin(int maxMessages, TimeSpan interval)
+        {
+            _maxMessages = maxMessages;
+            _interval = interval;
+            _messageTimestamps = new ConcurrentDictionary<string, ConcurrentQueue<DateTime>>();
+        }
+
+        public void OnServerStarted(NetworkServer server) { }
+        public void OnServerStopped(NetworkServer server) { }
+
+        public void OnClientConnected(Connection client)
+        {
+            _messageTimestamps[client.Id] = new ConcurrentQueue<DateTime>();
+        }
+
+        public void OnClientDisconnected(Connection client, DisconnectReason reason, Exception exception)
+        {
+            _messageTimestamps.TryRemove(client.Id, out _);
+        }
+
+        public void OnDataReceived(Connection client, byte[] data, string stringData, bool isBinary)
+        {
+            if (!_messageTimestamps.TryGetValue(client.Id, out var queue)) return;
+
+            var now = DateTime.UtcNow;
+            queue.Enqueue(now);
+
+            // Remove old timestamps
+            while (queue.TryPeek(out var oldest) && now - oldest > _interval)
+                queue.TryDequeue(out _);
+
+            if (queue.Count > _maxMessages)
+            {
+                Console.WriteLine($"[{Name}] Client {client.RemoteEndPoint} exceeded rate limit. Disconnecting...");
+                
+                // Force disconnect
+                client.TcpClient?.Close();
+            }
+        }
+    }
+}

EonaCat.Connections/Processors/JsonDataProcessor.cs

@@ -7,6 +7,9 @@ using Timer = System.Timers.Timer;
 
 namespace EonaCat.Connections.Processors
 {
+    // This file is part of the EonaCat project(s) which is released under the Apache License.
+    // See the LICENSE file or go to https://EonaCat.com/license for full license details.
+
     /// <summary>
     /// Processes incoming data streams into JSON or text messages per client buffer.
     /// </summary>