#:package System.IO.Ports@10.0.8
#:property LangVersion=latest
#:property Nullable=enable

using System;
using System.Linq;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
using System.IO.Ports;

namespace ResponseTester
{
    class Program
    {
        private static int spamCounter = 2048;

        static private Dictionary<string, DateTime> commands = Enumerable.Range(1, spamCounter).ToDictionary(i => $"{i}:ping\n", i => DateTime.MaxValue);
        static private Dictionary<string, DateTime> responses = new Dictionary<string, DateTime>();

        static private void SerialReader(SerialPort serialPort, CancellationToken ct)
        {
            var responseCounter = 0;
            var timeout = DateTime.Now.AddSeconds(10);
            while (!ct.IsCancellationRequested && responseCounter < spamCounter && DateTime.Now < timeout)
            {
                try
                {
                    var response = serialPort.ReadLine();
                    responses[response] = DateTime.Now;
                    Console.WriteLine($"Received response: {response.Trim()}");
                    responseCounter++;
                }
                catch (TimeoutException)
                {
                    // Ignore timeout exceptions
                }
            }
        }

        static void Main(string[] args)
        {
            Console.WriteLine("Starting response tester...");

            var portName = "COM30";
            var baudrate = 115200;

            using var serialPort = new SerialPort(portName, baudrate, Parity.None, 8, StopBits.One);
            serialPort.ReadTimeout = 100;
            serialPort.DtrEnable = true;          // ← neu
            serialPort.RtsEnable = true;          // ← neu (manche Stacks brauchen es)
            serialPort.NewLine = "\n";            // ← neu, sonst erwartet ReadLine "\r\n"
            try
            {
                serialPort.Open();
            }
            catch (Exception ex)
            {
                Console.WriteLine($"Failed to open serial port: {ex.Message}");
                return;
            }

            CancellationTokenSource cts = new();
            var task = Task.Run(() => SerialReader(serialPort, cts.Token), cts.Token);

            var burst = 16;
            var counter = 0;
            foreach(var command in commands.Keys.ToList())
            {
                serialPort.Write(command);
                commands[command] = DateTime.Now;
                Console.WriteLine($"Sent command: {command.Trim()}");
                
                counter++;
                if (counter % burst == 0)                {
                    Thread.Sleep(10);
                }
            }

            task.Wait();
            cts.Dispose();

            var latencies = new List<TimeSpan>();
            foreach(var command in commands)
            {
                var prefix = command.Key.Split(':')[0] + ":";
                var response = responses.Keys.FirstOrDefault(r => r.StartsWith(prefix));
                if (response != null)
                {
                    var latency = responses[response] - command.Value;
                    latencies.Add(latency);
                    Console.WriteLine($"Command: {command.Key.Trim()} | Response: {response.Trim()} | Latency: {latency.TotalMilliseconds} ms");
                }
                else Console.WriteLine($"Command: {command.Key.Trim()} | Response: No response received");
            }

            var averageLatency = latencies.Count > 0 ? TimeSpan.FromMilliseconds(latencies.Average(l => l.TotalMilliseconds)) : TimeSpan.Zero;
            Console.WriteLine($"Average Latency: {averageLatency.TotalMilliseconds} ms");
        }
    }
}