source: binary-improvements/7dtd-server-fixes/src/TelnetCommands/PrivateMassageConnections.cs@ 123

using System;
using System.Collections.Generic;

public class PrivateMassageConnections
{
        private static Dictionary<ClientInfo, ClientInfo> senderOfLastPM = new Dictionary<ClientInfo, ClientInfo>();

        public static void SetLastPMSender(ClientInfo _sender, ClientInfo _receiver) {
                if (senderOfLastPM.ContainsKey(_receiver))
                        senderOfLastPM[_receiver] = _sender;
                else
                        senderOfLastPM.Add(_receiver, _sender);
        }

        public static ClientInfo GetLastPMSenderForPlayer(ClientInfo _player) {
                if (senderOfLastPM.ContainsKey(_player))
                        return senderOfLastPM[_player];
                return null;
        }
}