using System.Net;
using System.Net.Sockets;
using System.Text;

namespace Server
{
	internal class Server
	{
		private static readonly int BUFFER_SIZE = 256;

		static async Task Main(string[] args)
		{
			Socket serverSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
			IPEndPoint endPoint = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 20000);
			serverSocket.Bind(endPoint);
			serverSocket.Listen(1000);

			while (true)
			{
				Socket clientSocket = await serverSocket.AcceptAsync();
				Console.WriteLine(clientSocket.RemoteEndPoint);
				ThreadPool.QueueUserWorkItem(ReadAsync, clientSocket);
			}
		}

		private static async void ReadAsync(object? state)
		{
			if (state == null)
				return;

			Socket clientSocket = (Socket)state;
			while (true)
			{
				byte[] buffer = new byte[BUFFER_SIZE];
				int n1 = await clientSocket.ReceiveAsync(buffer, SocketFlags.None);
				if (n1 < 1)
				{
					Console.WriteLine("Client is disconnected...");
					clientSocket.Dispose();
					return;
				}

				Console.WriteLine(Encoding.UTF8.GetString(buffer));
			}
		}
	}
}