using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace Love2DBackend
{
    class Program
    {
        static async Task Main(string[] args)
        {
            Console.WriteLine("LÖVE2D Backend - UDP Server");
            Console.WriteLine("Starting server on port 7777...");

            using (var udpServer = new UdpClient(7777))
            {
                Console.WriteLine("Server listening on 0.0.0.0:7777");

                var cts = new CancellationTokenSource();

                // Handle Ctrl+C gracefully
                Console.CancelKeyPress += (s, e) =>
                {
                    e.Cancel = true;
                    cts.Cancel();
                };

                try
                {
                    while (!cts.Token.IsCancellationRequested)
                    {
                        var result = await udpServer.ReceiveAsync(cts.Token);
                        var message = Encoding.UTF8.GetString(result.Buffer);
                        var clientEndpoint = result.RemoteEndPoint;

                        Console.WriteLine($"[{clientEndpoint}] {message}");

                        // Echo back
                        var response = Encoding.UTF8.GetBytes($"Echo: {message}");
                        await udpServer.SendAsync(response, response.Length, clientEndpoint);
                    }
                }
                catch (OperationCanceledException)
                {
                    Console.WriteLine("Server stopped.");
                }
            }
        }
    }
}