private static string HandleConsoleCommands(IClientConnectable client, string incomingData)
{
if (client == null)
{
throw new ArgumentNullException("Error: NetworkServer.HandleConsoleCommands null client");
}
if (incomingData == null)
{
throw new ArgumentNullException("Error: NetworkServer.HandleConsoleCommands null data");
}
if (incomingData.Length == 0)
{
throw new ArgumentNullException("Error: NetworkServer.HandleConsoleCommands empty data");
}
List <string> args = new List <string>(incomingData.Split(' '));
if (args.Count > 0)
{
string arg0 = args[0].ToLower();
if (arg0.Contains("help"))
{
return("Console commands: '/disconnect' or '/dcon' disconnects client");
}
else if (arg0.Contains("disconnect") || arg0.Contains("dcon"))
{
DisconnectClient(client, "You have been disconnected from the server.", "client disconnect");
return("Client Disconnect Confirm");
}
}
return($"Unhandled or unknown command: {incomingData}, type '/help' for help.");
}
private static void AddClient(IClientConnectable client)
{
if (client == null)
{
throw new ArgumentNullException("Error: NetworkServer.AddClient null client");
}
lock (Clients)
{
Clients.Add(client);
}
Log($" > {client.Nickname} connected!\n");
}
public static bool TryTransmitToClient(IClientConnectable client, string text)
{
if (client == null)
{
throw new ArgumentNullException("Error: NetworkServer.TransmitToClient null client");
}
if (!Clients.Contains(client))
{
return(false);
}
if (text == null)
{
throw new ArgumentNullException("Error: NetworkServer.TransmitToClient null string");
}
if (text.Length == 0)
{
throw new ArgumentException("Error: NetworkServer.TransmitToClient empty string");
}
if (text.Length > 0)
{
try
{
byte[] msg = Encoding.ASCII.GetBytes(text);
client.Socket.SendAsync(msg, SocketFlags.None);
return(true);
}
catch (SocketException ex)
{
ErrorMessage(ex);
RemoveClient(client, false);
return(false);
}
catch (Exception ex)
{
ErrorMessage(ex);
RemoveClient(client, false);
return(false);
}
}
return(false);
}
private static void RemoveClient(IClientConnectable client, bool wasGraceful, string extraInfo = "")
{
if (client == null)
{
throw new ArgumentNullException("Error: NetworkServer.RemoveClient null client");
}
if (extraInfo == null)
{
extraInfo = "";
}
// extraInfo.Length == 0 OK
if (wasGraceful)
{
if (extraInfo != "")
{
Log($" > {client.Nickname} disconnected: {extraInfo}\n");
}
else
{
Log($" > {client.Nickname} disconnected!\n");
}
}
if (client.Socket.Connected)
{
client.Socket.Close();
}
lock (Clients)
{
if (Clients.Contains(client))
{
Clients.Remove(client);
}
}
}
private static void TryAcceptConnection <T>(IAsyncResult AR) where T : IClientConnectable
{
if (listenerClosed)
{
return;
}
try
{
Socket newSocket = listenerSocket.EndAccept(AR);
IClientConnectable newClient = (T)Activator.CreateInstance(typeof(T), new object[] { newSocket, ++ClientCounter });
AddClient(newClient);
newClient.Socket.BeginReceive(newClient.Buffer, 0, BufferSize, SocketFlags.None, new AsyncCallback(OnReceiveData), newClient);
listenerSocket.BeginAccept(new AsyncCallback(TryAcceptConnection <T>), null);
if (TryTransmitToClient(newClient, "\nYou are now connected to the network server. For connection-related support, type '/help'.\n\n"))
{
TryTransmitToClient(newClient, newClient.GetImmediateReplyForClient());
}
}
catch (Exception ex)
{
ErrorMessage(ex);
}
}
// =======================================================================================
// ASYNC RECEIVER
// =======================================================================================
private static void OnReceiveData(IAsyncResult ar)
{
IClientConnectable thisClient = (IClientConnectable)ar.AsyncState;
if (thisClient == null)
{
return;
}
if (!Clients.Contains(thisClient))
{
Log($"Discarding listener for {thisClient}.\n");
return;
}
int bytesReceived = 0;
if (thisClient.Socket.Connected)
{
try
{
bytesReceived = thisClient.Socket.EndReceive(ar);
if (bytesReceived > 0)
{
string incomingData = Encoding.ASCII.GetString(thisClient.Buffer, 0, bytesReceived).Trim();
if (incomingData.Length > 0 && incomingData.Substring(0, 1) == "/")
{
string feedback = HandleConsoleCommands(thisClient, incomingData);
if (TryTransmitToClient(thisClient, $"{feedback}\n"))
{
thisClient.Socket.BeginReceive(thisClient.Buffer, 0, BufferSize, 0, new AsyncCallback(OnReceiveData), thisClient);
}
}
else
{
Log($"{thisClient.Nickname}: [{incomingData}]\n");
thisClient.HandleInputFromClientToServer(incomingData);
if (TryTransmitToClient(thisClient, thisClient.GetImmediateReplyForClient()))
{
thisClient.Socket.BeginReceive(thisClient.Buffer, 0, BufferSize, 0, new AsyncCallback(OnReceiveData), thisClient);
}
}
}
}
catch (SocketException ex)
{
switch (ex.ErrorCode)
{
case 10054:
Log($"Error ({ex.ErrorCode}): {thisClient.Nickname} dropped!\n");
RemoveClient(thisClient, false);
break;
default:
ErrorMessage($"SocketException ({ex.ErrorCode}): {ex.Message}!", ex);
break;
}
if (thisClient.Socket.Connected)
{
thisClient.Socket.Close();
}
}
catch (Exception ex)
{
ErrorMessage(ex);
}
}
}
