annotations/Azaion.Common/Services/GpsMatcher/GpsMatcherClient.cs

using System.Diagnostics;
using System.IO;
using Azaion.Common.DTO;
using Azaion.Common.Events;
using MediatR;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using NetMQ;
using NetMQ.Sockets;

namespace Azaion.Common.Services;

public interface IGpsMatcherClient : IDisposable
{
    Task StartMatching(StartMatchingEvent startEvent);
    void Stop();
}

public class StartMatchingEvent
{
    public string      RouteDir           { get; set; } = null!;
    public string      SatelliteImagesDir { get; set; } = null!;
    public int         ImagesCount        { get; set; }
    public GeoPoint      GeoPoint             { get; set; } = null!;
    public int         Altitude           { get; set; } = 400;
    public double      CameraSensorWidth  { get; set; } = 23.5;
    public double      CameraFocalLength  { get; set; } = 24;

    public override string ToString() =>
        $"{RouteDir},{SatelliteImagesDir},{ImagesCount},{GeoPoint.Lat},{GeoPoint.Lon},{Altitude},{CameraSensorWidth},{CameraFocalLength}";
}

public class GpsMatcherClient : IGpsMatcherClient
{
    private readonly IMediator _mediator;
    private readonly ILogger<GpsMatcherClient> _logger;
    private readonly string _requestAddress;
    private readonly RequestSocket _requestSocket = new();
    private readonly string _subscriberAddress;
    private readonly SubscriberSocket _subscriberSocket = new();
    private readonly NetMQPoller _poller = new();

    public GpsMatcherClient(IMediator mediator, IOptions<GpsDeniedClientConfig> gpsConfig, ILogger<GpsMatcherClient> logger)
    {
        _mediator = mediator;
        _logger = logger;
        try
        {
            using var process = new Process();
            process.StartInfo = new ProcessStartInfo
            {
                FileName = Constants.ExternalGpsDeniedPath,
                Arguments = $"zeromq --rep {gpsConfig.Value.ZeroMqPort} --pub {gpsConfig.Value.ZeroMqReceiverPort}",
                WorkingDirectory = Constants.EXTERNAL_GPS_DENIED_FOLDER,
                CreateNoWindow = true
            };
            process.Start();
        }
        catch (Exception e)
        {
            _logger.LogError(e, e.ToString());
        }

        _requestAddress = $"tcp://{gpsConfig.Value.ZeroMqHost}:{gpsConfig.Value.ZeroMqPort}";
        _requestSocket.Connect(_requestAddress);

        _subscriberAddress = $"tcp://{gpsConfig.Value.ZeroMqHost}:{gpsConfig.Value.ZeroMqReceiverPort}";
        _subscriberSocket.Connect(_subscriberAddress);
        _subscriberSocket.Subscribe("");
        _subscriberSocket.ReceiveReady += async (sender, e) => await ProcessClientCommand(sender, e);

        _poller.Add(_subscriberSocket);
        _poller.RunAsync();
    }

    private async Task ProcessClientCommand(object? sender, NetMQSocketEventArgs e)
    {
        while (e.Socket.TryReceiveFrameString(TimeSpan.FromMilliseconds(100), out var str))
        {
            try
            {
                if (string.IsNullOrEmpty(str))
                    continue;

                switch (str)
                {
                    case "FINISHED":
                        await _mediator.Publish(new GPSMatcherFinishedEvent());
                        break;
                    case "OK":
                        await _mediator.Publish(new GPSMatcherJobAcceptedEvent());
                        break;
                    default:
                        var parts = str.Split(',');
                        if (parts.Length != 6)
                            throw new Exception("Matching Result Failed");

                        var filename = Path.GetFileNameWithoutExtension(parts[1]);
                        await _mediator.Publish(new GPSMatcherResultEvent
                        {
                            Index = int.Parse(parts[0]),
                            Image = filename,
                            GeoPoint = new GeoPoint(double.Parse(parts[2]), double.Parse(parts[3])),
                            KeyPoints = int.Parse(parts[4]),
                            MatchType = Enum.TryParse<MatchTypeEnum>(parts[5], out var type) ? type : MatchTypeEnum.None
                        });
                        break;
                }
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, ex.Message);
            }
        }
    }

    public async Task StartMatching(StartMatchingEvent e)
    {
        _requestSocket.SendFrame(e.ToString());
        _requestSocket.TryReceiveFrameString(TimeSpan.FromMilliseconds(300), out var response);
        if (response != "OK")
        {
            _logger.LogError(response);
            await _mediator.Publish(new SetStatusTextEvent(response ?? "", true));
        }
    }

    public void Stop() => _requestSocket.SendFrame("STOP");

    public void Dispose()
    {
        _poller.Stop();
        _poller.Dispose();

        _requestSocket.SendFrame("EXIT");
        _requestSocket.Disconnect(_requestAddress);
        _requestSocket.Dispose();

        _subscriberSocket.Disconnect(_subscriberAddress);
        _subscriberSocket.Dispose();
    }
}