tbf/TBF/Rig/Network/Camera/CJMS11/Camera.cs

///
/// Copyright (c) 2017-2022 Sensus Slovensko a.s.
///
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Linq;
using System.Linq.Expressions;
using System.Net;
using System.Net.Sockets;
using System.Runtime.CompilerServices;
using System.Security.Cryptography;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;
using log4net;
using Renci.SshNet;
using Common;
using Config.Entities;
using FluentNHibernate.Conventions;
using Newtonsoft.Json;
using TBF.Rig.Network.Telnet;
using TBF.Resources;
using TBF.Rig.Generic;
using TBF.Rig.Network.Camera.CJMS11.POJO;
using TBF.Rig.Network.Camera.common;
using TBF.Rig.Network.Camera.RoiForFixedStartCJMS11;
using TBF.UiBridge;

namespace TBF.Rig.Network.Camera.CJMS11
{
	/// <summary>
	/// This class implements: (1) Camera device, (2) Measurement operation
	/// </summary>
	public class Camera : ComponentBase, GenericDevices.ICamera, Generic.IDevice, IOperation
	{
		private static readonly ILog log = LogManager.GetLogger(typeof(Camera));
		public override string ToString()
		{
			return string.Format("{0}: Name={1}, Addr={2}, IP={3}, s/n={4}, SD={5}",
								 this.GetType().Namespace.Substring(8),
								 CameraCfg.Name,
								 CameraCfg.HardwareAddress,
								 CameraCfg.DebugLevel == DebugMode.Simulate ? "simulated" : ((ipAddress == null) ? "not detected" : ipAddress.ToString()),
                                 CameraCfg.DebugLevel == DebugMode.Simulate ? "simulated" : (string.IsNullOrEmpty(cpuSerialNr) ? "not detected" : cpuSerialNr),
                                 CameraCfg.DebugLevel == DebugMode.Simulate ? "simulated" : (string.IsNullOrEmpty(sdCardVer) ? "not detected" : sdCardVer));
		}


		private const int iPort = 32456;
		string ClpUserName = string.Empty;          /// Either "tbf" or "pi" after a successful detection
		const string ClpPassword = "C1ern4V0d4";


		private readonly SemaphoreSlim cameraReadLock = new SemaphoreSlim(1, 1);
		//private readonly SemaphoreSlim cameraWriteLock = new SemaphoreSlim(1, 1);

		///
		/// Properties
		///
		public readonly CameraCfg CameraCfg;
		public readonly AdapterJMS.Netadapter NetAdapter;

		private RoiCfg roiConfiguration;
		public RoiCfg RoiConfiguration
		{
			get { 
				if (roiConfiguration!=null) {return roiConfiguration;}
				else { roiConfiguration = GetFirstRoiCfgChild(); return roiConfiguration; }
			}
			set { if (roiConfiguration == null) roiConfiguration = value;}
		}
		
		private RoiForFixedStartCJMS11.Roi _roi;
		public RoiForFixedStartCJMS11.Roi CamRoi
		{
			get { 
				if (_roi!=null) {return _roi;}
				else { _roi = GetFirstRoiChild(); return _roi; }
			}
			set { if (_roi == null) _roi = value;}
		}

		public IPAddress IPAddress { get { return ipAddress; } }
		IPAddress ipAddress;

		public string CpuHardware { get { return cpuHardware; } }
		string cpuHardware;

		public string CpuRevision { get { return cpuRevision; } }
		string cpuRevision;

		public string CpuSerialNr { get { return cpuSerialNr; } }
		string cpuSerialNr;

		public string SDCardVer { get { return sdCardVer; } }
		string sdCardVer;

		public bool Running { get { return running; } }
		bool running;

        public bool ShowOverlayRect { set { showOverlayRect = value; } }
        bool showOverlayRect = false;

        public Rectangle OverlayRect { set { overlayRect = value; } }
        Rectangle overlayRect;

        public int OverlayThickness { set { overlayThickness = value; } }
        int overlayThickness;

		public int CameraIdx { get { return cameraIdx; } }
		int cameraIdx;
		/// 
		static int nextCameraIdx = 0;

		static int GetCameraIdx() { return nextCameraIdx++; }	/// Used in Initialize()

		///
		/// Telnet support
		///
		const string TelnetPrompt = "$ ";
		const bool   TelnetSkipFirstLine = true;

		private TerminalDlg terminalDlg;
		string sha1sumResponse;
		JmsMessage jmsMessage;
		bool sha1sumResponseProcessed;

		///
		/// scp support
		///

		PasswordConnectionInfo connectionInfo;
		
		
		
		///
		/// MJpeg RTP protocol support
		///
		public bool CameraConnected{ get {return cameraTcpClient != null && cameraTcpClient.Connected;} }
		int cameraTcpLocalPort;
		TcpClient cameraTcpClient;
		private NetworkStream cameraStream = null;
		//private StreamWriter cameraWriter = null;
		private StreamReader cameraReader = null;
		private Image lastImage;
		private bool lockCameraInitialisation = false;

		Thread liveStreamListenerThread;
		private bool stopLiveStreamListenerFlag;
		
		public bool IsGrabImageListenerThreadAlive { get { return grabImageListenerThread != null && grabImageListenerThread.IsAlive; } }
		Thread grabImageListenerThread;
		private bool stopGrabImageListenerFlag;
		public void SetStopGrabImageListenerFlag() { stopGrabImageListenerFlag = true; }

		Thread stopUIListenerThread;
		private bool stopUIListenerFlag;

		Thread saveImageListenerThread;
		private bool stopSaveImageListenerFlag;
		public bool IsSaveImageListenerThreadAlive { get { return saveImageListenerThread != null && saveImageListenerThread.IsAlive; } }

		/// <summary>
		/// Send images part
		/// </summary>
		private Task<IReadOnlyList<TimedCameraImage>> sendImagesTask;
		private CancellationTokenSource sendImagesCts;

		public bool IsSendImagesInProgress => sendImagesTask != null && !sendImagesTask.IsCompleted;
		
		///
		/// ROI related parameters
		///
		RoisAndResults roisAndResults;
		/// 
		public void ClearRoiParams()
		{
			roisAndResults.ClearRoiParams();
		}

		public int RegisterRoi(string roiParams)
		{
			return roisAndResults.RegisterRoi(roiParams);
		}

		public int GetResult(int roiHandle, out long timeMs)
		{
			return roisAndResults.GetResult(roiHandle, out timeMs);
		}


		public Camera() { }

		public Camera(Generic.IComponentCfg cfg, IList<Generic.IComponent> components)
			: base(cfg)
		{
			CameraCfg = cfg as CameraCfg;

           // NetAdapter = TbfComponents.FindComponent(cfg.ParentName, components) as TBF.Rig.Network.AdapterJMS.Netadapter;
			//if (NetAdapter == null) throw new ArgumentNullException("no network adapter");
		}


		public override void Initialize()
		{
			cameraIdx = GetCameraIdx();

            running = false;
            terminalDlg = null;
            roisAndResults = new RoisAndResults();	/// object for measurement results, writes/reads to/from this object are locked

            // if (CameraCfg.DebugLevel == DebugMode.Simulate)
            // {
            //     UiBridge.Bridge.OnCameraInfo(cameraIdx, string.Format("{0}  s/n {1}  si simulated", Name, CameraCfg.HardwareAddress));
            //     return;
            // }

			/// Detect a camera
			CameraDetectionResult cameraDetectionResult = null;
			try
			{
				cameraDetectionResult = Task
					.Run(() => DetectJMSCamera())
					.GetAwaiter()
					.GetResult();
			}
			catch (Exception exc)
			{
				log.Error($"Camera detection failed: {exc.Message}");

				cameraDetectionResult = new CameraDetectionResult
				{
					IsDetected = false
				};
			}
			
			//test
			// var detectJmsCamera1 = DetectJMSCamera("192.168.0.170",32456);
			// var detectJmsCamera2 = DetectJMSCamera("192.168.0.168",32456);
			// Task.WaitAll(detectJmsCamera, detectJmsCamera1, detectJmsCamera2);

			
			if (CameraCfg.DebugLevel == DebugMode.AutoDetect)
			{
				CameraCfg.DebugLevel = cameraDetectionResult.IsDetected ? DebugMode.DetectedOn : DebugMode.DetectedOff;
			}
			else if (!cameraDetectionResult.IsDetected)
			{
				throw new Exception(string.Format("{0}={1}", Strings.Address, CameraCfg.HardwareAddress));
			}

			if (cameraDetectionResult.IsDetected)
			{
				ipAddress = cameraDetectionResult.IpAddress;

				UiBridge.Bridge.OnCameraInfo(
					cameraIdx,
					string.Format(
						"{0}  ver.{1}  {2}  s/n {3}",
						Name,
						sdCardVer,
						ipAddress,
						CameraCfg.HardwareAddress));

				// start live stream, grab image, ...  listener thread
				UiBridge.Bridge.CameraUICmdHandler -= HandleCameraUiCmd;
				UiBridge.Bridge.CameraUICmdHandler += HandleCameraUiCmd;

				//PromptCameraReceivedHandler -= OnPromptReceivedCamera;
				//PromptCameraReceivedHandler += OnPromptReceivedCamera;
				
				ImageCameraHandler -= OnPromptImageReceived;
				ImageCameraHandler += OnPromptImageReceived;
				
				ImagesCameraHandler -= OnPromptImagesReceived;
				ImagesCameraHandler += OnPromptImagesReceived;
				
			}
			else
			{
                UiBridge.Bridge.OnCameraInfo(this.cameraIdx, string.Format("{0}  s/n {1}  was not detected", Name, CameraCfg.HardwareAddress));
                log.FatalFormat("'{0}' NOT detected: Id={1} addr={2}", Name, CameraIdx, CameraCfg.HardwareAddress);
			}
		}

		private void OnPromptImageReceived(object sender, PromptReceivedImageEventArgs e)
		{
			if (e == null || e.image == null || cameraIdx != e.idxCamera)
			{
				return;
			}

			/*
			 * Bridge dostane svoju vlastnú kópiu.
			 */
			Image bridgeImage = CloneImageToBitmap(e.image);

			UiBridge.Bridge.OnImage( e.idxCamera, bridgeImage);

			log.Debug( $"Image received from camera: {e.idxCamera}, pushed to bridge UI!");
		}
		
		private void OnPromptImagesReceived(object sender, PromptReceivedImagesEventArgs e)
		{
			if (e != null && e.image != null)
			{
				if (this.cameraIdx == e.idxCamera)
				{
					UiBridge.Bridge.OnImage(e.idxCamera, e.image);
					log.Debug($"Image received from camera: {e.idxCamera}, pushed to bridge UI!");
				}
			}
		}

		public void StopDevice()
		{
            if ((CameraCfg.DebugLevel != DebugMode.Simulate) && (CameraCfg.DebugLevel != DebugMode.DetectedOff))
            {
                running = false;

                
                stopLiveStreamListenerFlag = true;
                stopGrabImageListenerFlag = true;
                
            }
		}

		public void StopDevice2()
		{
            if ((CameraCfg.DebugLevel != DebugMode.Simulate) && (CameraCfg.DebugLevel != DebugMode.DetectedOff))
            {
                
                if (liveStreamListenerThread != null) liveStreamListenerThread.Join(50);
                if (grabImageListenerThread != null) grabImageListenerThread.Join(50);

                if (cameraTcpClient != null)
                {
                    cameraTcpClient.Close();
                    cameraTcpClient = null;
                }
            }
		}

		public void RunDeviceBefore()
		{
            if ((CameraCfg.DebugLevel != DebugMode.Simulate) && (CameraCfg.DebugLevel != DebugMode.DetectedOff))
            {
                if (sha1sumResponse != null && !sha1sumResponseProcessed)
                {
                    

                    sha1sumResponseProcessed = true;
                }
            }
		}
		public void RunDeviceAfter() { }


		void OnPromptReceived(object sndr, PromptReceivedJMSEventArgs a)
		{
			if (sha1sumResponse == null)
			{
				sha1sumResponse = a.Response;
				jmsMessage = a.Message;
			}
		}
		
		void OnReceivedImageX(object sndr, PromptReceivedImageEventArgs a)
		{
			if (a != null)
			{
				lastImage = a.image;
			}
		}
		
		void OnPromptReceivedCamera(object sndr, PromptReceivedJMSEventArgs a)
		{
			try
			{
				JmsPacket packet = new JmsPacket(a.Response);
				jmsMessage = packet.JmsMessage;
			}catch(Exception exc)
			{
				log.Error(exc.Message);
			}
		}

		void OnReceivedPackage(object sndr, PromptReceivedEventArgs a)
		{
			if (sha1sumResponse == null)
			{
				sha1sumResponse = a.Response;
				try
				{
					JmsPacket packet = new JmsPacket(a.Response);
					jmsMessage = packet.JmsMessage;
				}catch(Exception exc)
				{
					log.Error(exc.Message);
				}
			}
		}

        #region Configuration Change Handling

        public static void OnCfgChange(object sender, CfgChangeArgs args)
        {
            if (CfgChangeHandler == null) return;
            try { CfgChangeHandler(sender, args); }
            catch (Exception e) { log.Error("CfgChangeHandler(...) failed", e); }
        }

        public static event EventHandler<CfgChangeArgs> CfgChangeHandler;

        public override void StartChangeHandler()
        {
            CfgChangeHandler += delegate(object sender, CfgChangeArgs args)
            {
                CameraCfg tmpcfg = args.Cfg as CameraCfg;
                if (tmpcfg != null && tmpcfg.Name.Equals(Name))
                {
                    if (args.Command == CfgChangeCmd.CfgChange)
                    {
						CameraCfg.TestImagesMode = tmpcfg.TestImagesMode;
                        CameraCfg.TestImagesCount = tmpcfg.TestImagesCount;
                        CameraCfg.IPAddressCJMS = tmpcfg.IPAddressCJMS;
                    }
                }
            };
        }

        #endregion Configuration Change Handling


        public class CameraDetectionResult
        {
	        public bool IsDetected { get; set; }
	        public IPAddress IpAddress { get; set; }
	        public string Hardware { get; set; }
	        public string Revision { get; set; }
	        public string Serial { get; set; }
	        public string SdCardVersion { get; set; }
	        public string Response { get; set; }
	        public double Duration_ms { get; set; }
        }

        async Task<CameraDetectionResult> DetectJMSCamera()
        {
	        return await DetectJMSCamera(CameraCfg.IPAddressCJMS, iPort);
        }

        async Task<CameraDetectionResult> DetectJMSCamera( string ipAddressParam, int portParam) 
        {
	        var result = new CameraDetectionResult
	        {
		        IsDetected = false,
		        IpAddress = null,
		        Hardware = null,
		        Revision = null,
		        Serial = null,
		        SdCardVersion = null
	        };

	        if (CameraCfg.DebugLevel == DebugMode.Simulate)
	        {
		        result.IsDetected = true;
		        return result;
	        }

	        if (string.IsNullOrWhiteSpace(ipAddressParam))
	        {
		        log.Error( $"Camera {CameraCfg.Name}: IP address is missing.");
		        return result;
	        }

	        var detectionStopwatch = Stopwatch.StartNew();

	        try
	        {
		        using (var client = new TcpClient())
		        {
			        Task connectTask =
				        client.ConnectAsync(
					        ipAddressParam,
					        portParam);

			        Task timeoutTask =
				        Task.Delay(TimeSpan.FromSeconds(1));

			        Task completedTask =
				        await Task.WhenAny(
						        connectTask,
						        timeoutTask)
					        .ConfigureAwait(false);

			        if (completedTask == timeoutTask)
			        {
				        client.Close();
				        throw new TimeoutException( $"Camera connection timeout after 1 second: {ipAddressParam}:{portParam}");
			        }

			        // Vyhodí SocketException, ak ConnectAsync zlyhal.
			        await connectTask.ConfigureAwait(false);

			        if (!client.Connected)
			        {
				        throw new IOException( $"Camera connection was not established: {ipAddressParam}:{portParam}"); 
			        }

			        log.Debug( $"Camera connected: name={CameraCfg.Name}, IP={ipAddressParam}, port={portParam}");

			        using (NetworkStream stream = client.GetStream())
			        {
				        // Jeden reader pre celé spojenie.
				        var reader = new CameraLineReader( stream, 64 * 1024);

				        this.ipAddress = IPAddress.Parse(ipAddressParam);

				        /*
				         * 1. Nastavenie typu kamery
				         */
				        string configMessage = getConfigMessage();

				        JmsPacket typeCameraAnswer =
					        await SendCommandAndWaitToAnswerAsync(
							        stream,
							        reader,
							        CommandM.type_camera_,
							        configMessage,
							        5000,
							        CancellationToken.None)
						        .ConfigureAwait(false);

				        if (typeCameraAnswer == null || typeCameraAnswer.JmsMessage.Status != MessageStatus.ACK)
				        {
					        log.Warn( $"type_camera failed: " + $"camera={CameraCfg.Name}, " + $"IP={ipAddressParam}, " + $"answer={FormatPacketForLog(typeCameraAnswer)}");
				        }

				        /*
				         * 2. Prepare camera
				         */
				        JmsPacket prepareAnswer =
					        await SendCommandAndWaitToAnswerAsync(
							        stream,
							        reader,
							        CommandM.prepare_camera_,
							        null,
							        3000,
							        CancellationToken.None)
						        .ConfigureAwait(false);

				        bool alreadyOpened =
					        prepareAnswer != null &&
					        prepareAnswer.JmsMessage.Status ==
					        MessageStatus.NACK &&
					        !string.IsNullOrEmpty(
						        prepareAnswer.JmsMessage.Payload) &&
					        prepareAnswer.JmsMessage.Payload.Contains(
						        "OPENED");

				        if (alreadyOpened)
				        {
					        log.Debug( $"Camera already opened: " + $"name={CameraCfg.Name}, " + $"IP={ipAddressParam}"); 
				        }
				        else if (prepareAnswer == null || prepareAnswer.JmsMessage.Status != MessageStatus.ACK)
				        {
					        log.Warn( $"Prepare camera failed: " + $"camera={CameraCfg.Name}, " + $"IP={ipAddressParam}, " + $"answer={FormatPacketForLog(prepareAnswer)}");

					        /*
					         * Pokus o reset:
					         * close -> prepare
					         */
					        await SendCommandAndWaitToAnswerAsync(
							        stream,
							        reader,
							        CommandM.close_,
							        null,
							        2000,
							        CancellationToken.None)
						        .ConfigureAwait(false);

					        prepareAnswer =
						        await SendCommandAndWaitToAnswerAsync(
								        stream,
								        reader,
								        CommandM.prepare_camera_,
								        null,
								        3000,
								        CancellationToken.None)
							        .ConfigureAwait(false);

					        bool restartSucceeded =
						        prepareAnswer != null &&
						        (
							        prepareAnswer.JmsMessage.Status ==
							        MessageStatus.ACK ||
							        (
								        prepareAnswer.JmsMessage.Status ==
								        MessageStatus.NACK &&
								        !string.IsNullOrEmpty(
									        prepareAnswer.JmsMessage.Payload) &&
								        prepareAnswer.JmsMessage.Payload.Contains(
									        "OPENED")
							        )
						        );

					        if (!restartSucceeded)
					        {
						        log.Error(
							        $"Camera prepare restart failed: " +
							        $"camera={CameraCfg.Name}, " +
							        $"IP={ipAddressParam}, " +
							        $"answer={FormatPacketForLog(prepareAnswer)}");
					        }
				        }

				        /*
				         * 3.1 Warm-up grab after type_camera + prepare_camera.
				         *
				         * Hardvér po inicializácii potrebuje vytvoriť aspoň jeden obrázok.
				         * Obrázok pri detekcii nepotrebujeme ukladať ani posielať do UI.
				         */
				        JmsPacket grabAnswer =
					        await SendCommandAndWaitToAnswerAsync(
							        stream,
							        reader,
							        CommandM.grab_image_,
							        null,
							        10000,
							        CancellationToken.None)
						        .ConfigureAwait(false);

				        if (grabAnswer == null || grabAnswer.JmsMessage == null || grabAnswer.JmsMessage.Status != MessageStatus.ACK)
				        {
					        throw new IOException( $"Camera initialization grab failed: camera={CameraCfg.Name}, " +
						        $"IP={ipAddressParam}, answer={FormatPacketForLog(grabAnswer)}");
				        }

				        try
				        {
					        ParsedImage initializationImage =
						        grabAnswer.JmsMessage.getImage();

					        if (initializationImage == null)
					        {
						        throw new IOException( "Initialization grab returned no parsed image.");
					        }

					        if (initializationImage.Encoding != ImageType.BASE_64)
					        {
						        throw new IOException( $"Initialization grab returned unsupported encoding: " + $"{initializationImage.Encoding}");
					        }

					        // Vyvolá Base64 dekódovanie a tým overí, že obrázok je platný.
					        using (Image warmUpImage = initializationImage.Image)
					        {
						        if (warmUpImage == null)
						        {
							        throw new IOException(
								        "Initialization grab returned a null image.");
						        }

						        log.Debug(
							        $"Initialization image captured: " +
							        $"camera={CameraCfg.Name}, " +
							        $"IP={ipAddressParam}, " +
							        $"size={warmUpImage.Width}x{warmUpImage.Height}");
					        }
				        }
				        catch (Exception exc)
				        {
					        throw new IOException( $"Cannot process initialization image: camera={CameraCfg.Name}, " +
						        $"IP={ipAddressParam}, error={exc.Message}", exc);
				        }
				        
				        
				        
				        
				        /*
				         * 3.2 Status
				         */
				        JmsPacket statusAnswer =
					        await SendCommandAndWaitToAnswerAsync(
							        stream,
							        reader,
							        CommandM.status_,
							        null,
							        3000,
							        CancellationToken.None)
						        .ConfigureAwait(false);

				        if (statusAnswer == null ||
				            statusAnswer.JmsMessage.Status !=
				            MessageStatus.ACK)
				        {
					        log.Warn(
						        $"Camera status failed: " +
						        $"camera={CameraCfg.Name}, " +
						        $"IP={ipAddressParam}, " +
						        $"answer={FormatPacketForLog(statusAnswer)}");
				        }

				        /*
				         * 4. Get configuration
				         */
				        JmsPacket configAnswer =
					        await SendCommandAndWaitToAnswerAsync(
							        stream,
							        reader,
							        CommandM.get_cfg_,
							        null,
							        3000,
							        CancellationToken.None)
						        .ConfigureAwait(false);

				        if (configAnswer == null ||
				            configAnswer.JmsMessage.Status !=
				            MessageStatus.ACK)
				        {
					        throw new IOException(
						        $"Camera get_cfg failed: " +
						        $"camera={CameraCfg.Name}, " +
						        $"IP={ipAddressParam}, " +
						        $"answer={FormatPacketForLog(configAnswer)}");
				        }

				        result.IpAddress =
					        IPAddress.Parse(ipAddressParam);

				        result.Hardware = string.Empty;
				        result.Revision = string.Empty;
				        result.Serial = string.Empty;
				        result.SdCardVersion = string.Empty;
				        result.Response = configAnswer.ToString();
				        result.IsDetected = true;

				        string origin =
					        string.IsNullOrEmpty(configAnswer.MessageOrigin)
						        ? "unknown origin"
						        : configAnswer.MessageOrigin;

				        detectionStopwatch.Stop();
				        result.Duration_ms =
					        detectionStopwatch.Elapsed.TotalMilliseconds;

				        log.Debug(
					        $"Camera detected: " +
					        $"name={CameraCfg.Name}, " +
					        $"duration={result.Duration_ms:F0} ms, " +
					        $"HWAddress={CameraCfg.HardwareAddress}, " +
					        $"IP={ipAddressParam}, " +
					        $"origin={origin}");

				        /*
				         * Voliteľný cleanup.
				         *
				         * Ak má kamera po detekcii zostať otvorená,
				         * túto časť odstráň.
				         */
				        try
				        {
					        JmsPacket closeAnswer =
						        await SendCommandAndWaitToAnswerAsync(
								        stream,
								        reader,
								        CommandM.close_,
								        null,
								        2000,
								        CancellationToken.None)
							        .ConfigureAwait(false);

					        bool closeAccepted =
						        closeAnswer != null &&
						        (
							        closeAnswer.JmsMessage.Status == MessageStatus.ACK ||
							        (
								        closeAnswer.JmsMessage.Status == MessageStatus.NACK &&
								        !string.IsNullOrEmpty(closeAnswer.JmsMessage.Payload) &&
								        closeAnswer.JmsMessage.Payload.Contains(
									        "Close command already in progress")
							        )
						        );

					        if (!closeAccepted)
					        {
						        log.Warn(
							        $"Close after detection was not confirmed: " +
							        $"camera={CameraCfg.Name}, " +
							        $"answer={FormatPacketForLog(closeAnswer)}");
					        }
				        }
				        catch (Exception closeException)
				        {
					        log.Warn(
						        $"Camera close after detection failed: " +
						        $"{closeException.Message}");
				        }
						/*
						 * Disconnect after detection.
						 */
				        try
				        {
					        await SendCommandAsync(
							        stream,
							        CommandM.disconnect_,
							        CancellationToken.None,
							        null)
						        .ConfigureAwait(false);

					        log.Debug(
						        $"Disconnect command sent after detection: " +
						        $"camera={CameraCfg.Name}, IP={ipAddressParam}");
				        }
				        catch (Exception disconnectException)
				        {
					        log.Warn(
						        $"Camera disconnect after detection failed: " +
						        $"{disconnectException.Message}");
				        }

				        return result;
			        }
		        }
	        }
	        catch (TimeoutException exc)
	        {
		        detectionStopwatch.Stop();
		        result.Duration_ms =
			        detectionStopwatch.Elapsed.TotalMilliseconds;

		        log.Error(
			        $"Camera detection timeout: " +
			        $"name={CameraCfg.Name}, " +
			        $"HWAddress={CameraCfg.HardwareAddress}, " +
			        $"IP={ipAddressParam}, " +
			        $"port={portParam}, " +
			        $"duration={result.Duration_ms:F0} ms, " +
			        $"error={exc.Message}");
	        }
	        catch (SocketException exc)
	        {
		        detectionStopwatch.Stop();
		        result.Duration_ms =
			        detectionStopwatch.Elapsed.TotalMilliseconds;

		        log.Error(
			        $"Camera socket connection failed: " +
			        $"name={CameraCfg.Name}, " +
			        $"IP={ipAddressParam}, " +
			        $"port={portParam}, " +
			        $"socketError={exc.SocketErrorCode}, " +
			        $"error={exc.Message}");
	        }
	        catch (Exception exc)
	        {
		        detectionStopwatch.Stop();
		        result.Duration_ms =
			        detectionStopwatch.Elapsed.TotalMilliseconds;

		        log.Error(
			        $"Camera detection failed: " +
			        $"name={CameraCfg.Name}, " +
			        $"HWAddress={CameraCfg.HardwareAddress}, " +
			        $"IP={ipAddressParam}, " +
			        $"port={portParam}, " +
			        $"duration={result.Duration_ms:F0} ms, " +
			        $"error={exc.Message}",
			        exc);
	        }

	        result.IsDetected = false;
	        result.IpAddress = null;
	        result.Hardware = null;
	        result.Revision = null;
	        result.Serial = null;
	        result.SdCardVersion = null;

	        return result;
        }
        
        private static string FormatPacketForLog( JmsPacket packet)
        {
	        if (packet == null)
		        return "<null>";

	        if (packet.JmsMessage == null)
		        return "<packet without message>";

	        string payload = packet.JmsMessage.Payload;

	        if (!string.IsNullOrEmpty(payload) && payload.Length > 200) 
	        {
		        payload = payload.Substring(0, 200) + "...";
	        }

	        return $"command={packet.JmsMessage.Command}, " + $"status={packet.JmsMessage.Status}, " + $"payload={payload}";
        }

        private async Task ClearPendingResponsesAsync(StreamReader reader)
		{
			await cameraReadLock.WaitAsync();

			try
			{
				while (reader.Peek() >= 0)
				{
					string oldLine = reader.ReadLine();
					log.Debug("Discarded old camera response: " + oldLine);
				}
			}
			catch (IOException)
			{
			}
			catch (Exception exc)
			{
				log.Warn("ClearPendingResponses failed: " + exc.Message);
			}
			finally
			{
				cameraReadLock.Release();
			}
		}

		class SensorConfig{
			public string type { get; set; } = "all";
			public int width { get; set; } = 640;
			public int height { get; set; } = 480;
			public int fps { get; set; } = 10;
			public int exposure { get; set; } = 2000;
			public float brightness { get; set; } = 0.5f;
			public float contrast { get; set; } = 1.5f;
			public int nBuffersOverload { get; set; } = 5;

			public static string  getJsonString(SensorConfig sensorConfig)
			{
				string returnStr = JsonConvert.SerializeObject(sensorConfig, Formatting.Indented);
			
				returnStr = returnStr.Replace("\n", "");
				returnStr = returnStr.Replace("\r", "");
				return returnStr;	
			}
		}

		private RoiCfg  GetFirstRoiCfgChild()
		{
			/// Load the list of components from the database
			var session = TBF.DB.CreateSession(DBKind.Config);
			var cmptnEntities = session.QueryOver<Config.Entities.Component>().OrderBy(x => x.ItemNr).Asc.List();
			
		
			List<RoiCfg>  cfgs = new List<RoiCfg>();
			IList<IComponent> components = new List<Rig.Generic.IComponent>();
			foreach (var component in cmptnEntities)
			{
				if (String.Compare(component.Parent, Name, StringComparison.Ordinal) == 0)
				{
					IComponentFactory cmpntFactory = Rig.TbfComponents.CmpntFactoryFromClassName(component.ClassName);
					if (cmpntFactory == null) continue;
		
					IList<IComponent> tbfComponents = Rig.TbfComponents.LoadComponentsFromDB(cmptnEntities);
					IComponentCfg cmpntCfgFromCmpntEntity = cmpntFactory.CmpntCfgFromCmpntEntity(component);
		
					IComponent cmpnt = cmpntFactory.GetComponent(cmpntCfgFromCmpntEntity, components);
		
					RoiForFixedStartCJMS11.RoiCfg roi = cmpntCfgFromCmpntEntity as RoiForFixedStartCJMS11.RoiCfg;
		
					if (roi != null)
					{
						cfgs.Add(roi);
					}
				}
			}
		
			/// get fist found configuration 
			return cfgs.First();
		}
		
		private RoiForFixedStartCJMS11.Roi GetFirstRoiChild()
		{
			using (var session = TBF.DB.CreateSession(DBKind.Config))
			{
				var componentEntities = session
					.QueryOver<Config.Entities.Component>()
					.OrderBy(x => x.ItemNr)
					.Asc
					.List();

				IList<IComponent> components =
					Rig.TbfComponents.LoadComponentsFromDB(componentEntities);

				var roi = components
					.OfType<RoiForFixedStartCJMS11.Roi>()
					.FirstOrDefault(x =>
						x.Cfg != null &&
						string.Equals(
							x.Cfg.ParentName,
							Name,
							StringComparison.Ordinal));

				if (roi == null)
				{
					log.WarnFormat(
						"No ROI child was found for camera '{0}'.",
						Name);

					return null;
				}

				var roiCfg = roi.Cfg as RoiForFixedStartCJMS11.RoiCfg;

				if (roiCfg == null)
				{
					log.WarnFormat(
						"ROI '{0}' has an invalid configuration type.",
						roi.Name);

					return roi;
				}

				LoadProcedureParams(session, roiCfg);

				return roi;
			}
		}
		
		private void LoadProcedureParams(
			NHibernate.ISession session,
			RoiForFixedStartCJMS11.RoiCfg roiCfg)
		{
			if (roiCfg == null)
			{
				return;
			}

			var currentProcedure = StateMachine.Procedure;

			if (currentProcedure == null)
			{
				log.WarnFormat(
					"Cannot load procedure parameters for ROI '{0}': " +
					"current procedure is null.",
					roiCfg.Name);

				return;
			}

			var dbParams = session
				.QueryOver<ComponentProcedure>()
				.Where(x => x.CmpntName == roiCfg.Name)
				.And(x => x.Procedure == currentProcedure)
				.SingleOrDefault();

			if (dbParams == null)
			{
				log.WarnFormat(
					"No procedure parameters found for ROI '{0}', procedure '{1}'. " +
					"Using default values.",
					roiCfg.Name,
					currentProcedure);

				return;
			}

			if (roiCfg.ProcParams == null)
			{
				roiCfg.ProcParams = new ProcedureParams();
			}

			if (!roiCfg.ProcParams.UpdateFromDbEntity(dbParams))
			{
				log.WarnFormat(
					"Failed to deserialize procedure parameters for ROI '{0}', " +
					"procedure '{1}'.",
					roiCfg.Name,
					currentProcedure);

				return;
			}

			log.DebugFormat(
				"Loaded ROI procedure parameters: ROI='{0}', procedure='{1}', " +
				"RoiPicCount={2}, RoiDeltaTimeMs={3}.",
				roiCfg.Name,
				currentProcedure,
				roiCfg.ProcParams.RoiPicCount,
				roiCfg.ProcParams.RoiDeltaTimeMs);
		}
		
		private string getConfigMessage()
		{
			//CameraCfg
			SensorConfig sensorConfig = new SensorConfig();
			sensorConfig.height = RoiConfiguration.ImageFrame.Height;
			sensorConfig.width = RoiConfiguration.ImageFrame.Width;
			return SensorConfig.getJsonString(sensorConfig);
		}


		void CameraInfoRequest(UdpClient udpClient, int hardwareAddress)
		{
			string strToSend = string.Format("getinfo {0}", hardwareAddress);

		}

		void SetDateTime(UdpClient udpClient, DateTime dateTime)
		{
			string strToSend = string.Format("setdatetime {0:yyMMddHHmmss}", dateTime);

		}


		private CameraUICmd lockBrich = CameraUICmd.None;

		// Define the handler method
		private void HandleCameraUiCmd(object sender, CameraUICmdEventArgs e)
		{
			if(lockBrich != CameraUICmd.None && e.CameraUICmd != CameraUICmd.Stop)
				return;

			if (!(e.CameraIdx == -1 || e.CameraIdx == cameraIdx))
			{
				return;
			}

			try
			{
				//lock
				lockBrich = e.CameraUICmd;
				// Example reaction to event
				if (e.CameraUICmd == CameraUICmd.Live)
				{
					if (stopLiveStreamListenerFlag == false && liveStreamListenerThread != null &&
					    liveStreamListenerThread.IsAlive)
						return;
					log.Debug("Handle CameraUICmd received - Live");
					stopLiveStreamListenerFlag = false;
					stopUIListenerFlag = true;
					StartLiveStreamListener();
					//StartLiveStreamListener(IPAddress, iPort);
				}
				else if (e.CameraUICmd == CameraUICmd.Stop)
				{
					StopUiThreads();
					stopUIListenerFlag = true;
					log.Debug("Handle CameraUICmd received - Stop Live");
				}
				else if (e.CameraUICmd == CameraUICmd.Grab)
				{
					log.Debug($"Handle CameraUICmd received - GrabImage - camera idx: {cameraIdx}");
					//stopUIListenerFlag = true;
					StopUiThreads();
					StartGrabImageListener();
				}
				else if (e.CameraUICmd == CameraUICmd.SaveImage)
				{
					log.Debug("Handle CameraUICmd received - SaveImage - will end Live Stream");
					StopUiThreads();
					StartSaveImageListener();
				}
				else
				{

				}

				//Unlock - if is not in live - live will finish only by CameraUICmd.Stop
				if (lockBrich != CameraUICmd.Live)
					lockBrich = CameraUICmd.None;
			}
			catch (Exception exc)
			{
				lockBrich = CameraUICmd.None; //Unlock - solve hard lock
				stopUIListenerFlag = true;
			}
			
		}
		
		void SaveImageToFile(Image imageToSave)
		{

			
			if (imageToSave == null)
			{
				log.Error("Nothing to save in SaveImageToFile");
				return; // nothing to save
			}
			
			using (SaveFileDialog dialog = new SaveFileDialog())
			{
				dialog.Title = "Save Image As";
				dialog.Filter = "PNG Image|*.png|JPEG Image|*.jpg|Bitmap Image|*.bmp";
				dialog.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.MyPictures);
				dialog.FileName = "my_image.png";

				if (dialog.ShowDialog() == DialogResult.OK)
				{
					// Choose format based on extension
					var ext = System.IO.Path.GetExtension(dialog.FileName).ToLower();
					System.Drawing.Imaging.ImageFormat format = System.Drawing.Imaging.ImageFormat.Png;
					if (ext == ".jpg") format = System.Drawing.Imaging.ImageFormat.Jpeg;
					else if (ext == ".bmp") format = System.Drawing.Imaging.ImageFormat.Bmp;

					try
					{
						SaveImageToFile(imageToSave, dialog.FileName);
						MessageBox.Show("Image saved to: " + dialog.FileName);
					}catch(Exception exc)
					{
						MessageBox.Show("Error saving image: " + exc.Message);
					}
				}
			}
		}
		
		public void SaveImageToFile(
			Image imageToSave,
			string fileNamePath)
		{
			if (imageToSave == null)
			{
				throw new ArgumentNullException(nameof(imageToSave));
			}

			if (string.IsNullOrWhiteSpace(fileNamePath))
			{
				throw new ArgumentException(
					"Path to save is missing.",
					nameof(fileNamePath));
			}

			string directory =
				Path.GetDirectoryName(fileNamePath);

			if (!string.IsNullOrWhiteSpace(directory))
			{
				Directory.CreateDirectory(directory);
			}

			ImageFormat format =
				GetImageFormatFromFileName(fileNamePath);

			using (var clonedImage = CloneImageToBitmap(imageToSave))
			{
				clonedImage.Save(fileNamePath, format);
			}

			log.Debug("Image saved to: " + fileNamePath);
		}

		private static ImageFormat GetImageFormatFromFileName(
			string fileName)
		{
			string extension =
				Path.GetExtension(fileName)?.ToLowerInvariant();

			switch (extension)
			{
				case ".bmp":
					return ImageFormat.Bmp;

				case ".jpg":
				case ".jpeg":
					return ImageFormat.Jpeg;

				case ".png":
				default:
					return ImageFormat.Png;
			}
		}
		
		private static ImageCodecInfo GetEncoder(ImageFormat format)
		{
			return ImageCodecInfo.GetImageDecoders().FirstOrDefault(codec => codec.FormatID == format.Guid);
		}


		private Bitmap CloneImageToBitmap(Image originalImage)
		{
			return new Bitmap(originalImage);
		}
		private Image CloneImage(Image originalImage)
		{
			
			using (var ms = new MemoryStream())
			{
				originalImage.Save(ms, ImageFormat.Png); // Use a safe format for copying
				ms.Position = 0;
				return Image.FromStream(ms);
			}
		}

		public void StartSaveImageToFileListener(Image imageToSave, string fileName)
		{
			saveImageListenerThread = new Thread(() => SaveImageToFile(imageToSave, fileName));
			saveImageListenerThread.Start();
		}
		
		private Task saveImageTask;

		public bool IsSaveImageInProgress =>
			saveImageTask != null &&
			!saveImageTask.IsCompleted;
		
		public Task StartSaveImageToFileAsync( Image image, string fileName)
		{
			if (image == null)
				throw new ArgumentNullException(nameof(image));

			if (string.IsNullOrWhiteSpace(fileName))
				throw new ArgumentException(
					"File name is required.",
					nameof(fileName));

			if (saveImageTask != null && !saveImageTask.IsCompleted)
			{
				log.Warn( $"Image save already running: cameraIdx={cameraIdx}, file={fileName}");
				return saveImageTask;
			}

			saveImageTask = Task.Run( () => SaveImageToFile(image, fileName));

			return saveImageTask;
		}
		
		private void StartSaveImageListener()
		{
			Task<Image> saveImageTask = Task.Run(() => SaveImageListenerAsynch());
			var timeoutAnswerTask = Task.Delay(TimeSpan.FromSeconds(1));
			var completedAnswerTask = Task.WhenAny(saveImageTask, timeoutAnswerTask).Result;
			if (completedAnswerTask == timeoutAnswerTask)
			{
				log.Error("Connection attempt timed out after 1 second.");
				return;
			}
			try
			{
				SaveImageToFile(saveImageTask.Result);
			}
			catch (Exception exc)
			{
				MessageBox.Show("Error saving image: " + exc.Message);
			}
		}
		
		public void StartSaveImageListener(string filePath)
		{
			Task<Image> saveImageTask = Task.Run(() => SaveImageListenerAsynch());
			var timeoutAnswerTask = Task.Delay(TimeSpan.FromSeconds(1));
			var completedAnswerTask = Task.WhenAny(saveImageTask, timeoutAnswerTask).Result;
			if (completedAnswerTask == timeoutAnswerTask)
			{
				log.Error("Connection attempt timed out after 1 second.");
				return;
			}
			try
			{
				SaveImageToFile(saveImageTask.Result);
			}
			catch (Exception exc)
			{
				MessageBox.Show("Error saving image: " + exc.Message);
			}
		}
		
		private void EstablishCameraConnection(ref TcpClient camTcpClient, string localIP, int localPort)
		{
			
			var connectTask = camTcpClient.ConnectAsync(localIP, localPort);
			var timeoutTask = Task.Delay(TimeSpan.FromSeconds(1));
					
			var completedTask = Task.WhenAny(connectTask, timeoutTask).Result;

			if (completedTask == timeoutTask)
			{
				throw new TimeoutException("Connection attempt timed out after 1 second.");
			}
		}
		
		private void EstablishCameraConnectionRepeticaly(ref TcpClient camTcpClient, string localIP, int localPort)
		{
			int[] timeoutIntervals = new int[] { 500, 1000 };

			foreach (int interval in timeoutIntervals)
			{
				// Dispose previous TcpClient if needed
				//camTcpClient?.Close();
				//camTcpClient = new TcpClient();

				try
				{
					// Begin connection attempt
					var connectTask = camTcpClient.ConnectAsync(localIP, localPort);
					var timeoutTask = Task.Delay(interval);

					var completedTask = Task.WhenAny(connectTask, timeoutTask).GetAwaiter().GetResult();

					if (completedTask == timeoutTask)
					{
						// Timed out
						continue;
					}

					// Check if the connect task completed successfully
					//connectTask.GetAwaiter().GetResult()); // Throws if failed

					if (camTcpClient.Connected)
					{
						// Connected successfully
						return;
					}
				}
				catch (Exception e)
				{
					// Ignore and continue to next retry interval
					continue;
				}
			}

			// If we reach here, all attempts failed
			throw new TimeoutException("Connection attempt timed out after multiple retries.");
		}
		private void EstablishCameraConnectionX(ref TcpClient camTcpClient, string localIP, int localPort)
		{
			Task connectTask = null;
			Task timeoutTask = null;
			Task completedTask = null;

			int[] timeoutIntervals = new int[] {100, 300, 500, 1000};

			foreach (int interval in timeoutIntervals)
			{
				if (camTcpClient.Connected)
				{
					return;
				}
				try
				{
					connectTask = camTcpClient.ConnectAsync(localIP, localPort);
					timeoutTask = Task.Delay(TimeSpan.FromMilliseconds(interval));

					completedTask = Task.WhenAny(connectTask, timeoutTask).Result;

					if (completedTask == timeoutTask)
					{
						continue;
					}
					break;
				}
				catch (Exception exc)
				{
					continue;
				}
			}
			
			if (completedTask == timeoutTask)
			{
				throw new TimeoutException("Connection attempt timed out after 1 second.");
			}

			if (connectTask == null || connectTask.IsFaulted || connectTask.IsCanceled)
			{
				throw new Exception("Connection attempt failed: " + connectTask.Exception.Message);
			}
			
			if (camTcpClient.Connected == false)
			{
				throw new Exception("Connection attempt failed: " + camTcpClient.Client.RemoteEndPoint.ToString());
			}
			
		}
		
		
		private async Task<TcpClient> ConnectCameraAsync(int timeoutMs, CancellationToken ct)
		{
			var client = new TcpClient();

			var connectTask = client.ConnectAsync(CameraCfg.IPAddressCJMS, iPort);
			var timeoutTask = Task.Delay(timeoutMs, ct);

			var completed = await Task.WhenAny(connectTask, timeoutTask);

			if (completed == timeoutTask)
			{
				client.Close();
				throw new TimeoutException($"Connection timeout after {timeoutMs} ms.");
			}

			await connectTask;

			log.Debug($"Camera connected to server {CameraCfg.IPAddressCJMS}:{iPort}.");
			ipAddress = IPAddress.Parse(CameraCfg.IPAddressCJMS);

			return client;
		}

		private async Task<TcpClient> ConnectCameraAsync(
			int timeoutMs,
			CancellationToken ct,
			int maxAttempts = 3,
			int retryDelayMs = 300)
		{
			Exception lastException = null;

			for (int attempt = 1; attempt <= maxAttempts; attempt++)
			{
				ct.ThrowIfCancellationRequested();

				var client = new TcpClient();

				try
				{
					log.Debug( $"Connecting to camera: cameraIdx={cameraIdx}, IP={CameraCfg.IPAddressCJMS}, port={iPort}, " +
						$"attempt={attempt}/{maxAttempts}");

					Task connectTask = client.ConnectAsync( CameraCfg.IPAddressCJMS, iPort);
					Task timeoutTask = Task.Delay( timeoutMs, ct);

					Task completedTask = await Task.WhenAny(connectTask, timeoutTask).ConfigureAwait(false);

					if (completedTask == timeoutTask)
					{
						ct.ThrowIfCancellationRequested();

						client.Close();

						throw new TimeoutException( $"Connection timeout after {timeoutMs} ms. Attempt {attempt}/{maxAttempts}.");
					}

					// Dôležité: načíta prípadnú SocketException.
					await connectTask.ConfigureAwait(false);

					if (!client.Connected)
					{
						throw new SocketException(
							(int)SocketError.NotConnected);
					}

					client.NoDelay = true;

					log.Debug( $"Camera connected: cameraIdx={cameraIdx}, IP={CameraCfg.IPAddressCJMS}, port={iPort}, " +
						$"attempt={attempt}");

					ipAddress =
						IPAddress.Parse(
							CameraCfg.IPAddressCJMS);

					return client;
				}
				catch (OperationCanceledException)
				{
					client.Close();
					throw;
				}
				catch (Exception exc)
				{
					client.Close();
					lastException = exc;

					log.Warn( $"Camera connection attempt failed: cameraIdx={cameraIdx}, IP={CameraCfg.IPAddressCJMS}, " +
						$"attempt={attempt}/{maxAttempts}, error={exc.Message}");

					if (attempt < maxAttempts)
					{
						await Task.Delay(
								retryDelayMs,
								ct)
							.ConfigureAwait(false);
					}
				}
			}

			throw new IOException(
				$"Unable to connect to camera {CameraCfg.IPAddressCJMS}:{iPort} after {maxAttempts} attempts.",
				lastException);
		}

		public async Task<Image> SaveImageListenerAsynch()
		{
			saveCts?.Cancel();
			saveCts = new CancellationTokenSource();

			return await SaveImageListenerAsynch(saveCts.Token);
		}

		public async Task<Image> SaveImageListenerAsynch(CancellationToken ct)
		{
			Image imageToReturn = null;

			await cameraOperationLock.WaitAsync(ct);

			try
			{
				using (TcpClient client = await ConnectCameraAsync(1000, ct))
				using (NetworkStream stream = client.GetStream())
				{
					var reader = new CameraLineReader(
						stream,
						64 * 1024);
					
					JmsPacket prepareAnswer =
						await SendCommandAndWaitToAnswerAsync(
								stream,
								reader,
								CommandM.prepare_camera_,
								null,
								3000,
								ct)
							.ConfigureAwait(false);
					bool alreadyOpened =
						prepareAnswer != null &&
						prepareAnswer.JmsMessage.Status ==
						MessageStatus.NACK &&
						!string.IsNullOrEmpty(
							prepareAnswer.JmsMessage.Payload) &&
						prepareAnswer.JmsMessage.Payload.Contains(
							"OPENED");

					if (alreadyOpened)
					{
						log.Debug( $"Camera already OPENED: " + $"cameraIdx={cameraIdx}, " + $"IP={CameraCfg.IPAddressCJMS}");
					}
					else if (prepareAnswer == null || prepareAnswer.JmsMessage.Status != MessageStatus.ACK)
					{
						log.Error( $"Prepare camera failed: " + $"cameraIdx={cameraIdx}, " + $"IP={CameraCfg.IPAddressCJMS}");
						return null;
					}

					JmsPacket grabAnswer =
						await SendCommandAndWaitToAnswerAsync(
								stream,
								reader,
								CommandM.grab_image_,
								null,
								10000,
								ct)
							.ConfigureAwait(false);

					if (grabAnswer == null || grabAnswer.JmsMessage.Status != MessageStatus.ACK)
					{
						log.Error( $"Grab image failed: " + $"cameraIdx={cameraIdx}, " + $"IP={CameraCfg.IPAddressCJMS}");
						return null;
					}

					ParsedImage parsedImage = grabAnswer.JmsMessage.getImage();
					
					if (parsedImage == null)
					{
						log.Error( $"Parsed image is null: " + $"cameraIdx={cameraIdx}");
						return null;
					}
					
					if (parsedImage.Encoding != ImageType.BASE_64)
					{
						log.Error( $"Unsupported image encoding: " + $"cameraIdx={cameraIdx}, " + $"encoding={parsedImage.Encoding}");
						return null;
					}



					imageToReturn = parsedImage.Image;

					if (imageToReturn == null)
					{
						log.Error( $"Decoded image is null: " + $"cameraIdx={cameraIdx}");
						return null;
					}

					DrawOverlay(imageToReturn);

					await TryCloseCameraAsync( stream, reader).ConfigureAwait(false);

					return imageToReturn;
				}
			}
			catch (OperationCanceledException)
			{
				log.Debug( $"Save image cancelled: cameraIdx={cameraIdx}");
				return null;
			}
			catch (TimeoutException exc)
			{
				log.Error( $"Save image timeout: cameraIdx={cameraIdx}, IP={CameraCfg.IPAddressCJMS}, error={exc.Message}");
				return null;
			}
			catch (Exception exc)
			{
				log.Error( $"Save image exception: cameraIdx={cameraIdx}, IP={CameraCfg.IPAddressCJMS}, error={exc.Message}", exc);
				return null;
			}
			finally
			{
				cameraOperationLock.Release();
			}
		}


		void StopUiThreads()
		{
			liveCts?.Cancel();
			grabCts?.Cancel();
			saveCts?.Cancel();
			sendImagesCts?.Cancel();
			
			stopLiveStreamListenerFlag = true;
			stopGrabImageListenerFlag = true;
			stopUIListenerFlag = true;
			
			
			log.Debug("Handle CameraUICmd StopUIListener");
			var taskStopUi = Task.Run(StopUiListener);
			var timeoutTask = Task.Delay(TimeSpan.FromSeconds(5));
					
			var completedTask = Task.WhenAny(taskStopUi, timeoutTask).Result;

			if (completedTask == timeoutTask)
			{
				stopUIListenerFlag = true;
				throw new TimeoutException("Connection attempt timed out after 5 second.");
			}
			CloseCameraResources();
		}

		void StopUiListener()
		{
			stopUIListenerFlag = false;
			while (!stopUIListenerFlag)
			{
				stopLiveStreamListenerFlag = true;
				stopGrabImageListenerFlag = true;

				if ((liveStreamListenerThread != null && liveStreamListenerThread.IsAlive) ||
				    (grabImageListenerThread != null && grabImageListenerThread.IsAlive))
				{ 
					Thread.Sleep(100);		
				}
				else
				{
					stopUIListenerFlag = true;
				}
			}
			//stopLiveStreamListenerFlag = false;
			//stopGrabImageListenerFlag = false;
		}
		
		
		

		public bool IsGrabImageInProgress
		{
			get
			{
				return grabImageTask != null &&
				       !grabImageTask.IsCompleted;
			}
		}

		public Task GrabImageTask
		{
			get { return grabImageTask; }
		}
		
		public void StartGrabImageListener()
		{
		 
			_ = StartGrabImageListenerAsync();
		}
		
		
		public Task<Image> StartGrabImageListenerAsync(
			bool retryUntilValidImage = false,
			int maxAttempts = 1,
			int retryDelayMs = 200)
		{
			if (grabImageTask != null && !grabImageTask.IsCompleted)
			{
				log.Warn(
					$"Grab already running: cameraIdx={cameraIdx}, " +
					$"IP={CameraCfg.IPAddressCJMS}");

				return grabImageTask;
			}

			grabCts?.Cancel();
			grabCts?.Dispose();

			grabCts = new CancellationTokenSource();

			if (!retryUntilValidImage)
			{
				maxAttempts = 1;
			}

			maxAttempts = Math.Max(1, maxAttempts);
			retryDelayMs = Math.Max(0, retryDelayMs);

			grabImageTask = GrabImageListenerWithRetryAsync(
				grabCts.Token,
				maxAttempts,
				retryDelayMs);

			return grabImageTask;
		}
		
		private async Task EstablishCameraConnectionAsync(
			TcpClient client,
			string ip,
			int port,
			int timeoutMs)
		{
			Task connectTask = client.ConnectAsync(ip, port);
			Task timeoutTask = Task.Delay(timeoutMs);

			Task completedTask = await Task.WhenAny(connectTask, timeoutTask);

			if (completedTask == timeoutTask)
				throw new TimeoutException($"Connection attempt timed out after {timeoutMs} ms.");

			await connectTask;
		}
		
		private Task<Image> grabImageTask;
		private CancellationTokenSource grabCts;
		//private CancellationTokenSource liveCts;
		private CancellationTokenSource saveCts;

		private readonly SemaphoreSlim cameraOperationLock = new SemaphoreSlim(1, 1);



		private async Task<Image> GrabImageListenerWithRetryAsync(
			CancellationToken ct,
			int maxAttempts,
			int retryDelayMs)
		{
			bool lockAcquired = false;

			try
			{
				await cameraOperationLock.WaitAsync(ct).ConfigureAwait(false);

				lockAcquired = true;

				for (int attempt = 1;
				     attempt <= maxAttempts;
				     attempt++)
				{
					ct.ThrowIfCancellationRequested();

					Image image = null;

					try
					{
						log.Debug( $"Starting grab image attempt: cameraIdx={cameraIdx}, attempt={attempt}/{maxAttempts}");

						image = await GrabImageSingleAttemptAsync(ct).ConfigureAwait(false);

						if (IsValidGrabbedImage(image))
						{
							/*
							 * Obrázok upravíme ešte predtým,
							 * než ho sprístupníme iným threadom.
							 */
							ImageUtils.Rotate(
								image,
								RoiConfiguration.ImageRotation);

							DrawOverlay(image);

							/*
							 * UI dostane vlastnú Image inštanciu.
							 * Originál zostáva pre návrat z Task<Image>
							 * a následné uloženie do súboru.
							 */
							Image imageForUi = CloneImageToBitmap(image);

							try
							{
								OnImageReceived( this, cameraIdx, imageForUi, ImageRotation.None);
							}
							catch
							{
								imageForUi.Dispose();
								throw;
							}

							log.Debug( $"Valid image received: cameraIdx={cameraIdx}, attempt={attempt}/{maxAttempts}, " +
								$"size={image.Width}x{image.Height}");

							return image;
						}
						image?.Dispose();

						log.Warn(
							$"Invalid image received: " +
							$"cameraIdx={cameraIdx}, " +
							$"attempt={attempt}/{maxAttempts}");
					}
					catch (OperationCanceledException)
					{
						image?.Dispose();
						throw;
					}
					catch (Exception exc)
					{
						image?.Dispose();

						log.Warn(
							$"Grab image attempt failed: " +
							$"cameraIdx={cameraIdx}, " +
							$"attempt={attempt}/{maxAttempts}, " +
							$"error={exc.Message}");
					}

					if (attempt < maxAttempts &&
					    retryDelayMs > 0)
					{
						await Task.Delay(retryDelayMs, ct)
							.ConfigureAwait(false);
					}
				}

				log.Error(
					$"No valid image received after all attempts: " +
					$"cameraIdx={cameraIdx}, " +
					$"attempts={maxAttempts}");

				UiBridge.Bridge.OnImage(cameraIdx, null);

				return null;
			}
			catch (OperationCanceledException)
			{
				log.Debug(
					$"Grab image cancelled: " +
					$"cameraIdx={cameraIdx}");

				throw;
			}
			finally
			{
				if (lockAcquired)
				{
					cameraOperationLock.Release();
				}
			}
		}
		
		private static bool IsValidGrabbedImage(Image image)
		{
			if (image == null)
			{
				return false;
			}

			try
			{
				if (image.Width <= 0 ||
				    image.Height <= 0)
				{
					return false;
				}

				// Vytvorenie Bitmap zároveň preverí,
				// či je obrázok použiteľný cez GDI+.
				using (var bitmap = new Bitmap(image))
				{
					return bitmap.Width > 0 &&
					       bitmap.Height > 0;
				}
			}
			catch
			{
				return false;
			}
		}

		private async Task<Image> GrabImageSingleAttemptAsync(
			CancellationToken ct)
		{
			TcpClient client = null;
			NetworkStream stream = null;
			CameraLineReader reader = null;

			try
			{
				client =
					await ConnectCameraAsync(5000, ct)
						.ConfigureAwait(false);

				stream = client.GetStream();

				reader = new CameraLineReader(
					stream,
					64 * 1024);

				JmsPacket prepareAnswer =
					await SendCommandAndWaitToAnswerAsync(
							stream,
							reader,
							CommandM.prepare_camera_,
							null,
							3000,
							ct)
						.ConfigureAwait(false);

				bool alreadyOpened =
					prepareAnswer != null &&
					prepareAnswer.JmsMessage != null &&
					prepareAnswer.JmsMessage.Status ==
					MessageStatus.NACK &&
					!string.IsNullOrEmpty(
						prepareAnswer.JmsMessage.Payload) &&
					prepareAnswer.JmsMessage.Payload.Contains(
						"OPENED");

				bool prepared =
					prepareAnswer != null &&
					prepareAnswer.JmsMessage != null &&
					prepareAnswer.JmsMessage.Status ==
					MessageStatus.ACK;

				if (!prepared && !alreadyOpened)
				{
					log.Warn(
						$"Prepare camera failed: " +
						$"cameraIdx={cameraIdx}, " +
						$"answer={FormatPacketForLog(prepareAnswer)}");

					return null;
				}

				if (alreadyOpened)
				{
					log.Debug(
						$"Camera already OPENED: " +
						$"cameraIdx={cameraIdx}");
				}

				await SendCommandAsync(
						stream,
						CommandM.grab_image_,
						ct,
						null)
					.ConfigureAwait(false);

				while (true)
				{
					ct.ThrowIfCancellationRequested();

					string response =
						await reader.ReadLineAsync(10000, ct)
							.ConfigureAwait(false);

					if (string.IsNullOrWhiteSpace(response))
					{
						continue;
					}

					JmsPacket packet;

					try
					{
						packet = new JmsPacket(response);
					}
					catch (Exception exc)
					{
						log.Warn(
							$"Cannot parse grab response: " +
							$"cameraIdx={cameraIdx}, " +
							$"error={exc.Message}");

						continue;
					}

					if (packet.JmsMessage == null)
					{
						continue;
					}

					if (packet.JmsMessage.Command !=
					    CommandM.grab_image_)
					{
						log.Debug(
							$"Unexpected response during grab: " +
							$"cameraIdx={cameraIdx}, " +
							$"command={packet.JmsMessage.Command}");

						continue;
					}

					if (packet.JmsMessage.Status !=
					    MessageStatus.ACK)
					{
						log.Warn(
							$"Grab image returned NACK: " +
							$"cameraIdx={cameraIdx}, " +
							$"payload={packet.JmsMessage.Payload}");

						return null;
					}

					ParsedImage parsedImage =
						packet.JmsMessage.getImage();

					if (parsedImage == null)
					{
						log.Warn(
							$"Parsed image is null: " +
							$"cameraIdx={cameraIdx}");

						return null;
					}

					if (parsedImage.Encoding !=
					    ImageType.BASE_64)
					{
						log.Warn(
							$"Unsupported image encoding: " +
							$"cameraIdx={cameraIdx}, " +
							$"encoding={parsedImage.Encoding}");

						return null;
					}

					Image image = parsedImage.Image;

					if (image == null)
					{
						log.Warn(
							$"Decoded image is null: " +
							$"cameraIdx={cameraIdx}");

						return null;
					}

					return image;
				}
			}
			catch (OperationCanceledException)
			{
				log.Debug(
					$"Grab image attempt cancelled: " +
					$"cameraIdx={cameraIdx}");

				throw;
			}
			catch (TimeoutException exc)
			{
				log.Warn(
					$"Grab image attempt timeout: " +
					$"cameraIdx={cameraIdx}, " +
					$"error={exc.Message}");

				return null;
			}
			catch (Exception exc)
			{
				log.Warn(
					$"Grab image attempt failed: " +
					$"cameraIdx={cameraIdx}, " +
					$"error={exc.Message}",
					exc);

				return null;
			}
			finally
			{
				if (stream != null &&
				    reader != null)
				{
					try
					{
						await TryCloseCameraAsync(
								stream,
								reader)
							.ConfigureAwait(false);
					}
					catch (Exception exc)
					{
						log.Warn(
							$"Grab cleanup failed: " +
							$"cameraIdx={cameraIdx}, " +
							$"error={exc.Message}");
					}
				}

				try
				{
					stream?.Dispose();
				}
				catch
				{
				}

				try
				{
					client?.Close();
					client?.Dispose();
				}
				catch
				{
				}
			}
		}


		private async Task TryCloseCameraAsync(
			NetworkStream stream,
			CameraLineReader reader)
		{
			/*
			 * CLOSE
			 *
			 * Na close ešte odpoveď očakávame.
			 */
			try
			{
				JmsPacket closeResponse =
					await SendCommandAndWaitToAnswerAsync(
							stream,
							reader,
							CommandM.close_,
							null,
							2000,
							CancellationToken.None)
						.ConfigureAwait(false);

				if (closeResponse == null ||
				    closeResponse.JmsMessage == null)
				{
					log.Warn(
						$"No close response: " +
						$"cameraIdx={cameraIdx}");

					return;
				}

				bool closeAccepted =
					closeResponse.JmsMessage.Status ==
					MessageStatus.ACK;

				bool closeAlreadyInProgress =
					closeResponse.JmsMessage.Status ==
					MessageStatus.NACK &&
					!string.IsNullOrEmpty(
						closeResponse.JmsMessage.Payload) &&
					closeResponse.JmsMessage.Payload.Contains(
						"Close command already in progress");

				if (closeAlreadyInProgress)
				{
					log.Debug(
						$"Camera close already in progress: " +
						$"cameraIdx={cameraIdx}");
				}
				else if (!closeAccepted)
				{
					log.Warn(
						$"Camera close returned NACK: " +
						$"cameraIdx={cameraIdx}, " +
						$"payload={closeResponse.JmsMessage.Payload}");
				}
			}
			catch (TimeoutException exc)
			{
				log.Warn(
					$"Close camera timeout: " +
					$"cameraIdx={cameraIdx}, " +
					$"error={exc.Message}");
			}
			catch (Exception exc)
			{
				log.Warn(
					$"Close camera failed: " +
					$"cameraIdx={cameraIdx}, " +
					$"error={exc.Message}");
			}

			/*
			 * DISCONNECT
			 *
			 * Dôležité: príkaz iba odošleme.
			 * Na odpoveď nečakáme.
			 */
			try
			{
				if (stream.CanWrite)
				{
					await SendCommandAsync(
							stream,
							CommandM.disconnect_,
							CancellationToken.None,
							null)
						.ConfigureAwait(false);

					log.Debug(
						$"Disconnect command sent: " +
						$"cameraIdx={cameraIdx}");
				}
			}
			catch (Exception exc)
			{
				log.Warn(
					$"Disconnect camera failed: " +
					$"cameraIdx={cameraIdx}, " +
					$"error={exc.Message}");
			}
		}


		private void CloseCameraResources()
		{
			cameraReader?.Close();
			cameraReader = null;
			//cameraWriter?.Close();
			//cameraWriter = null;
			cameraStream?.Close();
			cameraStream = null;
			cameraTcpClient?.Close();
			cameraTcpClient?.Dispose();
			cameraTcpClient = null;
		}

		public void CancelGrabImage()
		{
			try
			{
				grabCts?.Cancel();
			}
			catch (ObjectDisposedException)
			{
				// CTS už bolo uvoľnené.
			}
		}

		/// <summary>
		/// listener for multiple - repetetive image receiving
		/// </summary>
		/// <detail>
		/// method uses reader to receive data from camera
		/// </detail>
		/// <param name="localIP"></param>
		/// <param name="localPort"></param>

		// private void StartLiveStreamListener(IPAddress localIP, int localPort)
		// {
		// 	liveStreamListenerThread = new Thread(new ThreadStart(LiveStreamListener));
		// 	liveStreamListenerThread.Start();
		// }
		
		private CancellationTokenSource liveCts;
		private Task liveStreamTask;
		private static int maxAttempts = 4;
		private static int retryDelayMs = 1000;

		public void StartLiveStreamListener()
		{
			if (liveStreamTask != null && !liveStreamTask.IsCompleted)
			{
				log.Warn( $"Live stream already running: cameraIdx={cameraIdx}");
				return;
			}

			liveCts?.Cancel();
			liveCts?.Dispose();

			liveCts = new CancellationTokenSource();

			liveStreamTask = LiveStreamListenerAsync(liveCts.Token);
		}


		private async Task LiveStreamListenerAsync(
			CancellationToken ct)
		{
			bool lockAcquired = false;
			TcpClient client = null;
			NetworkStream stream = null;
			CameraLineReader reader = null;
			bool streamStarted = false;

			try
			{
				log.Debug(
					$"Live stream waiting for camera lock: " +
					$"cameraIdx={cameraIdx}");

				await cameraOperationLock
					.WaitAsync(ct)
					.ConfigureAwait(false);

				lockAcquired = true;

				log.Debug(
					$"Live stream acquired camera lock: " +
					$"cameraIdx={cameraIdx}");

				client = await ConnectCameraAsync(
							timeoutMs: 3000,
							ct: ct,
							maxAttempts: 3,
							retryDelayMs: 300)
						.ConfigureAwait(false);

				stream = client.GetStream();

				reader = new CameraLineReader( stream, 64 * 1024);

				JmsPacket prepare =
					await SendCommandAndWaitToAnswerAsync(
							stream,
							reader,
							CommandM.prepare_camera_,
							null,
							3000,
							ct)
						.ConfigureAwait(false);

				bool alreadyOpened =
					prepare != null &&
					prepare.JmsMessage != null &&
					prepare.JmsMessage.Status ==
					MessageStatus.NACK &&
					!string.IsNullOrEmpty(
						prepare.JmsMessage.Payload) &&
					prepare.JmsMessage.Payload.Contains(
						"OPENED");

				bool prepared =
					prepare != null &&
					prepare.JmsMessage != null &&
					prepare.JmsMessage.Status ==
					MessageStatus.ACK;

				if (!prepared && !alreadyOpened)
				{
					log.Error( $"Prepare camera for live stream failed: cameraIdx={cameraIdx}, answer={FormatPacketForLog(prepare)}");
					return;
				}

				if (alreadyOpened)
				{
					log.Debug( $"Camera already opened for live stream: cameraIdx={cameraIdx}");
				}

				JmsPacket start =
					await SendCommandAndWaitToAnswerAsync(
							stream,
							reader,
							CommandM.start_stream_images_,
							null,
							5000,
							ct)
						.ConfigureAwait(false);

				if (start == null || start.JmsMessage == null || start.JmsMessage.Status != MessageStatus.ACK)
				{
					log.Error( $"Unable to start live stream: cameraIdx={cameraIdx}, answer={FormatPacketForLog(start)}");
					return;
				}

				streamStarted = true;

				log.Debug( $"Live stream started: cameraIdx={cameraIdx}");

				while (!ct.IsCancellationRequested)
				{
					string response =
						await reader.ReadLineAsync(
								10000,
								ct)
							.ConfigureAwait(false);

					if (string.IsNullOrWhiteSpace(response))
						continue;

					JmsPacket packet =
						new JmsPacket(response);

					if (packet.JmsMessage == null)
						continue;

					if (packet.JmsMessage.Command !=
					    CommandM.grab_image_)
					{
						log.Debug( $"Unexpected packet during live stream: cameraIdx={cameraIdx}, command={packet.JmsMessage.Command}");
						continue;
					}

					if (packet.JmsMessage.Status !=
					    MessageStatus.ACK)
					{
						log.Warn( $"Live frame returned NACK: cameraIdx={cameraIdx}, payload={packet.JmsMessage.Payload}");
						continue;
					}

					ParsedImage parsed = packet.JmsMessage.getImage();

					if (parsed == null || parsed.Encoding != ImageType.BASE_64)
					{
						continue;
					}

					Image image = parsed.Image;

					if (image == null)
						continue;

					DrawOverlay(image);

					OnImageReceived(
						this,
						cameraIdx,
						image,
						RoiConfiguration.ImageRotation,
						0,
						1);
				}
			}
			catch (OperationCanceledException)
			{
				log.Debug( $"Live stream cancelled: cameraIdx={cameraIdx}");
			}
			catch (TimeoutException exc)
			{
				log.Error( $"Live stream timeout: cameraIdx={cameraIdx}, IP={CameraCfg.IPAddressCJMS}, error={exc.Message}");
			}
			catch (SocketException exc)
			{
				log.Error( $"Live stream socket error: cameraIdx={cameraIdx}, IP={CameraCfg.IPAddressCJMS}, socketError={exc.SocketErrorCode}, " +
					$"error={exc.Message}");
			}
			catch (Exception exc)
			{
				log.Error( $"Live stream exception: cameraIdx={cameraIdx}, error={exc.Message}", exc);
				UiBridge.Bridge.OnImage( cameraIdx, null);
			}
			finally
			{
				/*
				 * Cleanup nesmie používať zrušený ct.
				 */
				if (stream != null &&
				    reader != null)
				{
					if (streamStarted)
					{
						try
						{
							await SendCommandAndWaitToAnswerAsync(
									stream,
									reader,
									CommandM.stop_stream_images_,
									null,
									2000,
									CancellationToken.None)
								.ConfigureAwait(false);
						}
						catch (Exception exc)
						{
							log.Warn(
								$"Stop live stream failed: " +
								$"cameraIdx={cameraIdx}, " +
								$"error={exc.Message}");
						}
					}

					try
					{
						await TryCloseCameraAsync(
								stream,
								reader)
							.ConfigureAwait(false);
					}
					catch (Exception exc)
					{
						log.Warn(
							$"Live stream cleanup failed: " +
							$"cameraIdx={cameraIdx}, " +
							$"error={exc.Message}");
					}
				}

				try
				{
					stream?.Dispose();
				}
				catch
				{
				}

				try
				{
					client?.Close();
					client?.Dispose();
				}
				catch
				{
				}

				if (lockAcquired)
				{
					cameraOperationLock.Release();
				}

				log.Debug( $"Live stream finished: cameraIdx={cameraIdx}");
			}
		}

		private void DrawOverlay(Image image)
		{
			if (image == null)
				return;

			if (!showOverlayRect || overlayThickness <= 0)
				return;

			using (Graphics g = Graphics.FromImage(image))
			using (Pen pen = new Pen(Color.Green, overlayThickness))
			{
				g.DrawRectangle(pen, overlayRect);
			}
		}


		//public void OnMeasurementDataReceived(object sender, MeasuredDataEventArgs msrmtData)
		//{
		//    string[] pulsesArr = msrmtData.MeasuredData.Split(new char[] { ';' });

		//    uint uiVal;
		//    if (result != null && result.Length + 1 == pulsesArr.Length && uint.TryParse(pulsesArr[0], out uiVal))
		//    {
		//        cameraTimeMs = (long)uiVal;

		//        for (int i = 0; i < result.Length; i++)
		//        {
		//            int val;
		//            if (int.TryParse(pulsesArr[i + 1], out val))
		//            {
		//                result[i] = Math.Abs(val);
		//            }
		//        }
		//    }
		//}


		public IOperation LiveStreamOp(bool hiRes)
		{
			int wid = hiRes ? 1280 : 640;
			int hgh = hiRes ? 960 : 480;
   
            //string command = string.Format("~/userland/build/bin/raspivid -t 0 -cd MJPEG -w {0} -h {1} -fps 30 -b 8000000 -o - | gst-launch-1.0 fdsrc ! \"image/jpeg,framerate=30/1\" ! jpegparse ! rtpjpegpay ! udpsink host={2} port={3}",
            //                               wid, hgh, NetAdapter.IPAddress, rtpUdpLocalPort);

			return new LiveStreamOp(this, command);
		}


		public IOperation GrabImagesOp(string[] imgFileNames, bool blackAndWhite, bool lowResolution, ImageRotation imageRotation)
		{
			return new GrabImagesOp(this, imgFileNames, blackAndWhite, lowResolution, imageRotation);
		}


		public IOperation MeasurementOp()
		{
			return null;
		}

		string command;
		bool measurementCommandSent;


		

		private void SendCommand(CommandM command)
		{
			try
			{
				if (cameraStream != null && cameraStream.CanWrite)
				{
					string commandStr = CommandMEnum.GetVal(command) + "\n";
					byte[] bytes = Encoding.ASCII.GetBytes(commandStr);

					cameraStream.Write(bytes, 0, bytes.Length);
					cameraStream.Flush();
				}
			}
			catch (Exception exc)
			{
				log.ErrorFormat("{0} SendCommand: {1}", Name, exc.Message);
			}
		}
		
		
		//
		private async Task<JmsPacket> SendCommandAndWaitToAnswerAsync(
    NetworkStream stream,
    CameraLineReader reader,
    CommandM command,
    string payload = null,
    int timeoutMs = 1000,
    CancellationToken ct = default)
{
    await SendCommandAsync( stream, command, ct, payload).ConfigureAwait(false);
    
    try
    {
        for (int iReads = 0; iReads < 6; iReads++)
        {
            string responseAnswer = await reader.ReadLineAsync( timeoutMs, ct).ConfigureAwait(false);

            if (string.IsNullOrWhiteSpace(responseAnswer))
                continue;

            log.Debug( $"Received from camera: idx={cameraIdx}, expected={command}, length={responseAnswer.Length}, prefix={GetLogPrefix(responseAnswer, 200)}");

            JmsPacket result;

            try
            {
                result = new JmsPacket(responseAnswer);
            }
            catch (Exception exc)
            {
                log.Warn( $"Cannot parse camera response: idx={cameraIdx}, length={responseAnswer.Length}, error={exc.Message}");
                continue;
            }

            if (result.JmsMessage == null)
            {
                log.Warn( $"Parsed packet contains no JmsMessage: idx={cameraIdx}");
                continue;
            }

            if (result.JmsMessage.Command == command)
            {
                return result;
            }

            log.Debug( $"Unexpected response command: idx={cameraIdx}, expected={command}, received={result.JmsMessage.Command}. Reading next response.");
        }

        log.Error( $"Expected camera response not received: idx={cameraIdx}, command={command}");
        return null;
    }
    catch (OperationCanceledException)
    {
        throw;
    }
    catch (TimeoutException)
    {
        throw;
    }
    catch (IOException ioEx)
    {
        log.Error( $"IO error while reading from camera: idx={cameraIdx}, command={command}, error={ioEx.Message}");
        return null;
    }
    catch (Exception exc)
    {
        log.Error( $"Error while reading from camera: idx={cameraIdx}, command={command}, error={exc.Message}", exc);
        return null;
    }
}
		
		private static string GetLogPrefix(
			string value,
			int maximumLength)
		{
			if (string.IsNullOrEmpty(value))
				return string.Empty;

			if (value.Length <= maximumLength)
				return value;

			return value.Substring(0, maximumLength) +
			       "...";
		}

		public void Start()
		{
			///Prepare communication with the camera
			log.DebugFormat("Camera Start() - JMCameras.CameraCfg.IPAddressCJMS: {0}, CameraCfg.Port: {1}! ");
			StopUiListener();
			this.cameraTcpClient = new TcpClient();
			lockCameraInitialisation = true;

			try
			{
				EstablishCameraConnection(ref this.cameraTcpClient, CameraCfg.IPAddressCJMS, iPort);
			}catch(Exception exc)
			{
				log.ErrorFormat("Camera Start() - JMCameras.CameraCfg.IPAddressCJMS: {0}, CameraCfg.Port: {1}! Exception: {2}", CameraCfg.IPAddressCJMS, iPort, exc.Message);
				return;
			}

		}
		
		public Event Run()
		{

			return Event.None;
		}

		public void Stop()
		{
			if (measurementCommandSent)
			{
                log.WarnFormat("{0} SEND_COMMAND: cancel", Name);
                if (cameraStream.CanWrite)
                {
	                SendCommand(CommandM.close_);
	                SendCommand(CommandM.disconnect_);
                }
			}
		}
		
		
		///
		/// PromptReceviedEventHandler delegate and handler
		///
		public delegate void PromptCameraReceivedEventHandler(object sender, PromptReceivedJMSEventArgs e);
		public static event PromptCameraReceivedEventHandler PromptCameraReceivedHandler;
		
		/// <summary>
		/// This method is called from within this class when
		/// a prompt string was received from the telnet server.
		/// </summary>
		public static void OnPromptReceived(object sender, string response, JmsPacket package)
		{
			
			log.Info("Prompt received, response:" + Environment.NewLine + response);

			if (null != PromptCameraReceivedHandler)
			{
				try
				{
					PromptCameraReceivedHandler(sender, new PromptReceivedJMSEventArgs(response, package.JmsMessage));
				}
				catch (Exception e)
				{
					log.Info("Internal error: PromptReceivedHandler exception: " + e.Message);
				}
			}
		}
		
		///
		/// PromptReceviedEventHandler delegate and handler
		///
		public delegate void PromptImagesReceivedEventHandler(object sender, PromptReceivedImagesEventArgs e);
		public static event EventHandler<PromptReceivedImagesEventArgs> ImagesCameraHandler;
		public static event EventHandler<PromptReceivedImageEventArgs> ImageCameraHandler;
		
		
		public static void OnImageReceived(
			object sender,
			int idxImage,
			Image image,
			int iImageIdx = 0,
			int imageCount = 1)
		{
			if (image == null)
			{
				return;
			}

			log.Info( $"Image received from camera: {idxImage}, iImageIdx: {iImageIdx}, imageCount: {imageCount}");

			EventHandler<PromptReceivedImageEventArgs> handler = ImageCameraHandler;

			if (handler == null)
			{
				image.Dispose();
				return;
			}

			try
			{
				handler( sender, new PromptReceivedImageEventArgs( idxImage, image));
				log.Info( $"ImageCameraHandler reached camera: {idxImage}, iImageIdx: {iImageIdx}, imageCount: {imageCount}");
			}
			catch (Exception exc)
			{
				log.Error( $"ImageCameraHandler exception: cameraIdx={idxImage}, error={exc.Message}", exc);
				image.Dispose();
			}
		}
		
		/// <summary>
		/// This method is called from within this class when
		/// a prompt string was received from the telnet server.
		/// </summary>
		public static void OnImageReceived(object sender, int idxImage, Image image, ImageRotation imageRotation, int iImageIdx = 0, int imageCount = 1)
		{
			
			log.Info($"Image received from camera: {idxImage}, iImageIdx: {iImageIdx}, imageCount: {imageCount}");

			if (null != ImageCameraHandler)
			{
				try
				{
					//rotation
					ImageUtils.Rotate(image, imageRotation);
					
					//Send image to bridge
					ImageCameraHandler(sender, new PromptReceivedImageEventArgs(idxImage, image));
					log.Info($"ImageCameraHandler reached camera: {idxImage}, iImageIdx: {iImageIdx}, imageCount: {imageCount}");
				}
				catch (Exception ex)
				{
					log.Info("Internal error: PromptReceivedHandler exception: " + ex.Message);
				}
			}
		}
		
		/// <summary>
		/// This method is called from within this class when
		/// a prompt string was received from the telnet server.
		/// </summary>
		public static void OnImagesReceived(
			object sender,
			int cameraIndex,
			Image image,
			int imageIndex,
			int imageCount,
			DateTimeOffset? frameTime)
		{
			if (image == null)
			{
				return;
			}

			log.Info( $"Images received from camera: {cameraIndex}, imageIndex={imageIndex}, " +
			          $"imageCount={imageCount}, frameTime={frameTime:O}");

			EventHandler<PromptReceivedImagesEventArgs> handler = ImagesCameraHandler;

			if (handler == null)
			{
				image.Dispose();
				return;
			}

			try
			{
				handler( sender,
					new PromptReceivedImagesEventArgs(
						cameraIndex,
						imageIndex,
						imageCount,
						image,
						frameTime));

				log.Info( $"ImagesCameraHandler reached camera: {cameraIndex}, imageIndex={imageIndex}, " +
					$"imageCount={imageCount}");
			}
			catch (Exception exc)
			{
				log.Error( $"ImagesCameraHandler failed: cameraIdx={cameraIndex}, imageIndex={imageIndex}, " +
					$"error={exc.Message}", exc);
				image.Dispose();
			}
		}
		
		private async Task<string> ReadCameraLineAsync(
			NetworkStream stream, 
			int timeoutMs,  
			CancellationToken ct)
		{
			await cameraReadLock.WaitAsync(ct);

			try
			{
				var line = new List<byte>();
				var buffer = new byte[1];

				while (true)
				{
					Task<int> readTask = stream.ReadAsync(buffer, 0, 1, ct);
					Task timeoutTask = Task.Delay(timeoutMs, ct);

					Task completed = await Task.WhenAny(readTask, timeoutTask);

					if (completed == timeoutTask)
					{
						ct.ThrowIfCancellationRequested();
						throw new TimeoutException($"Camera {cameraIdx} read timeout after {timeoutMs} ms.");
					}

					int read = await readTask;

					if (read == 0)
						throw new IOException("Camera connection closed.");

					if (buffer[0] == '\n')
						break;

					if (buffer[0] != '\r')
						line.Add(buffer[0]);
				}

				return Encoding.ASCII.GetString(line.ToArray());
			}
			finally
			{
				cameraReadLock.Release();
			}
		}
		
		private readonly object cameraReadSyncLock = new object();
		
		private string ReadCameraLine(NetworkStream stream, int timeoutMs)
		{
			lock (cameraReadSyncLock)
			{
				stream.ReadTimeout = timeoutMs;

				var line = new List<byte>();

				while (true)
				{
					int b = stream.ReadByte(); // tu funguje ReadTimeout

					if (b == -1)
						throw new IOException("Camera connection closed.");

					if (b == '\n')
						break;

					if (b != '\r')
						line.Add((byte)b);
				}

				return Encoding.ASCII.GetString(line.ToArray());
			}
		}
		
		
		private async Task SendCommandAsync(NetworkStream stream, CommandM command, CancellationToken ct, string payload = null)
		{
			string commandStr = CommandMEnum.GetVal(command);

			if (!string.IsNullOrEmpty(payload))
			{
				commandStr += "=" + payload;
			}

			//commandStr += " ";
			byte[] bytes = Encoding.ASCII.GetBytes(commandStr + "\n");

			//await cameraWriteLock.WaitAsync();

			
				log.Info($"Sending command: '{commandStr}'");
				await stream.WriteAsync(bytes, 0, bytes.Length);
				await stream.FlushAsync();
				//stream.Write(bytes, 0, bytes.Length);
				//stream.Flush();
				
				//await stream.WriteLineAsync(commandStr);
				//await stream.FlushAsync();
				log.Info($"Command sent: '{commandStr}'");
			
		}
		
		
		private async Task<string> ReadCameraLineWithTimeout(NetworkStream stream, int timeoutMs)
		{
			var readTask = Task.Run(() => ReadCameraLine(stream, timeoutMs));
			var timeoutTask = Task.Delay(timeoutMs);

			var completed = await Task.WhenAny(readTask, timeoutTask);

			if (completed == timeoutTask)
			{
				try { stream.Close(); } catch { }
				try { cameraTcpClient?.Close(); } catch { }

				throw new TimeoutException($"Camera read timeout after {timeoutMs} ms.");
			}

			return await readTask;
		}

		
		//------------------------------ SEND PART --------------------------------------
		
		public Task<IReadOnlyList<TimedCameraImage>> StartSendImagesPreviewAsync(
				int count,
				int delayMs,
				string taskId)
		{
			if (count <= 0)
			{
				throw new ArgumentOutOfRangeException(
					nameof(count),
					"Image count must be greater than zero.");
			}

			if (delayMs < 0)
			{
				throw new ArgumentOutOfRangeException(
					nameof(delayMs),
					"Delay cannot be negative.");
			}

			if (string.IsNullOrWhiteSpace(taskId))
			{
				throw new ArgumentException(
					"Task ID is required.",
					nameof(taskId));
			}

			if (sendImagesTask != null &&
			    !sendImagesTask.IsCompleted)
			{
				log.Warn(
					$"Send images preview already running: " +
					$"cameraIdx={cameraIdx}, taskId={taskId}");

				return sendImagesTask;
			}

			sendImagesCts?.Cancel();
			sendImagesCts?.Dispose();

			sendImagesCts =
				new CancellationTokenSource();

			sendImagesTask =
				SendImagesPreviewListenerAsync(
					count,
					delayMs,
					taskId,
					sendImagesCts.Token);

			return sendImagesTask;
		}
		
		public void CancelSendImagesPreview()
		{
			try
			{
				sendImagesCts?.Cancel();
			}
			catch (ObjectDisposedException)
			{
			}
		}

		private async Task<IReadOnlyList<TimedCameraImage>> SendImagesPreviewListenerAsync(
				int requestedCount,
				int delayMs,
				string taskId,
				CancellationToken ct)
		{
			bool lockAcquired = false;
			TcpClient client = null;
			NetworkStream stream = null;
			CameraLineReader reader = null;

			var imagesByIndex = new Dictionary<int, TimedCameraImage>();

			try
			{
				await cameraOperationLock.WaitAsync(ct).ConfigureAwait(false);

				lockAcquired = true;

				client = await ConnectCameraAsync( timeoutMs: 5000, ct: ct).ConfigureAwait(false);
				stream = client.GetStream();

				reader = new CameraLineReader( stream, 64 * 1024);

				/*
				 * Kamera musí byť pripravená.
				 */
				JmsPacket prepareAnswer = await SendCommandAndWaitToAnswerAsync( 
							stream, 
							reader, 
							CommandM.prepare_camera_,
							null,
							3000,
							ct)
						.ConfigureAwait(false);

				bool prepared = prepareAnswer != null && 
				                prepareAnswer.JmsMessage != null && 
				                prepareAnswer.JmsMessage.Status == MessageStatus.ACK;

				bool alreadyOpened = 
					prepareAnswer != null && 
					prepareAnswer.JmsMessage != null && 
					prepareAnswer.JmsMessage.Status == MessageStatus.NACK &&
					!string.IsNullOrEmpty( prepareAnswer.JmsMessage.Payload) &&
					prepareAnswer.JmsMessage.Payload.Contains( "OPENED");

				if (!prepared && !alreadyOpened)
				{
					throw new IOException( $"Prepare camera for send failed: cameraIdx={cameraIdx}, " +
						$"answer={FormatPacketForLog(prepareAnswer)}");
				}

				var request = new SendImagesRequest { Count = requestedCount, Delay = delayMs, TaskId = taskId };
				string requestPayload = JsonConvert.SerializeObject( request, Formatting.None);

				log.Debug( $"Starting send images preview: cameraIdx={cameraIdx}, count={requestedCount}, " +
					$"delay={delayMs}, taskId={taskId}");

				/*
				 * Pri send_ neposielame cez
				 * SendCommandAndWaitToAnswerAsync(),
				 * pretože očakávame viac odpovedí.
				 */
				await SendCommandAsync(
						stream,
						CommandM.send_,
						ct,
						requestPayload)
					.ConfigureAwait(false);

				/*
				 * Timeout musí zahŕňať plánovaný čas snímania.
				 *
				 * count=5, delay=2050:
				 * približne 4 * 2050 ms medzi prvým a posledným frame
				 * plus rezerva na prenos Base64 obrázkov.
				 */
				int totalTimeoutMs = CalculateSendTimeout( requestedCount, delayMs);

				using (var timeoutCts = CancellationTokenSource.CreateLinkedTokenSource(ct))
				{
					timeoutCts.CancelAfter(totalTimeoutMs);

					while (imagesByIndex.Count < requestedCount)
					{
						timeoutCts.Token.ThrowIfCancellationRequested();

						string response = await reader.ReadLineAsync( 10000, timeoutCts.Token).ConfigureAwait(false);

						if (string.IsNullOrWhiteSpace(response))
						{
							continue;
						}

						JmsPacket packet;

						try
						{
							packet = new JmsPacket(response);
						}
						catch (Exception exc)
						{
							log.Warn( $"Cannot parse send response: cameraIdx={cameraIdx}, error={exc.Message}");
							continue;
						}

						if (packet.JmsMessage == null)
						{
							continue;
						}

						if (packet.JmsMessage.Command != CommandM.send_)
						{
							log.Debug( $"Unexpected packet during send: cameraIdx={cameraIdx}, command={packet.JmsMessage.Command}");
							continue;
						}

						if (packet.JmsMessage.Status != MessageStatus.ACK)
						{
							log.Warn( $"Send image returned NACK: cameraIdx={cameraIdx}, payload={packet.JmsMessage.Payload}");
							continue;
						}

						string payload = packet.JmsMessage.Payload;

						if (string.IsNullOrWhiteSpace(payload))
						{
							continue;
						}

						/*
						 * Posledný sumarizačný packet nemá
						 * pictureBase64 ani workerId.
						 */
						if (!PayloadContainsImage(payload))
						{
							TryLogSendSummary( payload, cameraIdx);
							continue;
						}

						SendImagePayload imagePayload;

						try
						{
							imagePayload = JsonConvert.DeserializeObject<SendImagePayload>(payload);
						}
						catch (Exception exc)
						{
							log.Warn( $"Cannot deserialize send image: cameraIdx={cameraIdx}, error={exc.Message}");
							continue;
						}

						if (imagePayload == null || string.IsNullOrWhiteSpace( imagePayload.PictureBase64))
						{
							continue;
						}

						if (!string.Equals( imagePayload.Status, "SUCCESSFUL", StringComparison.OrdinalIgnoreCase))
						{
							log.Warn( $"Send image status is not successful: cameraIdx={cameraIdx}, " +
								$"workerId={imagePayload.WorkerId}, status={imagePayload.Status}");
							continue;
						}

						/*
						 * workerId je podľa logu 1..count.
						 */
						int imageIndex = imagePayload.WorkerId;

						if (imageIndex <= 0)
						{
							log.Warn( $"Invalid send image index: cameraIdx={cameraIdx}, workerId={imageIndex}");
							continue;
						}

						/*
						 * Duplicitný packet ignorujeme.
						 */
						if (imagesByIndex.ContainsKey( imageIndex))
						{
							log.Warn( $"Duplicate send image: cameraIdx={cameraIdx}, workerId={imageIndex}");
							continue;
						}

						Image image = DecodeBase64Image( imagePayload.PictureBase64);

						if (!IsValidGrabbedImage(image))
						{
							image?.Dispose();

							log.Warn(
								$"Invalid send image: " +
								$"cameraIdx={cameraIdx}, " +
								$"workerId={imageIndex}");

							continue;
						}

						DateTimeOffset? frameTime =
							ParseFrameTime(
								imagePayload.FrameTime);

						/*
						 * Úpravy obrázka dokončíme ešte predtým,
						 * než ho odovzdáme UI.
						 */
						ImageUtils.Rotate(
							image,
							RoiConfiguration.ImageRotation);

						DrawOverlay(image);

						var timedImage =
							new TimedCameraImage
							{
								Index = imageIndex,
								TaskId =
									imagePayload.TaskId,
								FrameTime = frameTime,
								FrameTimeMillis =
									imagePayload.FrameTimeMillis,
								FrameGap =
									imagePayload.FrameGap,
								Image = image
							};

						imagesByIndex.Add(
							imageIndex,
							timedImage);

						/*
						 * UI dostane klon.
						 * Originál zostáva vo výslednom zozname.
						 */
						Image imageForUi = CloneImageToBitmap(image);

						OnImagesReceived(
							this,
							cameraIdx,
							imageForUi,
							imageIndex,
							requestedCount,
							frameTime);

						log.Debug( $"Send image received: cameraIdx={cameraIdx}, workerId={imageIndex}, " +
									$"received={imagesByIndex.Count}/{requestedCount}, frameTime={frameTime:O}, " +
									$"size={image.Width}x{image.Height}");
					}
				}

				List<TimedCameraImage> result =
					imagesByIndex
						.OrderBy(x => x.Key)
						.Select(x => x.Value)
						.ToList();

				log.Debug(
					$"Send images preview completed: " +
					$"cameraIdx={cameraIdx}, " +
					$"received={result.Count}, " +
					$"taskId={taskId}");

				return result;
			}
			catch (OperationCanceledException)
			{
				foreach (TimedCameraImage image
				         in imagesByIndex.Values)
				{
					image.Image?.Dispose();
				}

				log.Debug(
					$"Send images preview cancelled: " +
					$"cameraIdx={cameraIdx}, " +
					$"taskId={taskId}");

				throw;
			}
			catch (Exception exc)
			{
				foreach (TimedCameraImage image
				         in imagesByIndex.Values)
				{
					image.Image?.Dispose();
				}

				log.Error(
					$"Send images preview failed: " +
					$"cameraIdx={cameraIdx}, " +
					$"taskId={taskId}, " +
					$"error={exc.Message}",
					exc);

				UiBridge.Bridge.OnImage(
					cameraIdx,
					null);

				throw;
			}
			finally
			{
				if (stream != null &&
				    reader != null)
				{
					try
					{
						await TryCloseCameraAsync(
								stream,
								reader)
							.ConfigureAwait(false);
					}
					catch (Exception exc)
					{
						log.Warn(
							$"Send preview cleanup failed: " +
							$"cameraIdx={cameraIdx}, " +
							$"error={exc.Message}");
					}
				}

				try
				{
					stream?.Dispose();
				}
				catch
				{
				}

				try
				{
					client?.Close();
					client?.Dispose();
				}
				catch
				{
				}

				if (lockAcquired)
				{
					cameraOperationLock.Release();
				}
			}
		}
		
		private static int CalculateSendTimeout(
			int count,
			int delayMs)
		{
			/*
			 * Medzi count obrázkami je count - 1 intervalov.
			 * Pridáme 15 sekúnd rezervu na capture,
			 * Base64 a sieťový prenos.
			 */
			long captureDuration =
				(long)Math.Max(0, count - 1) *
				delayMs;

			long timeout =
				captureDuration + 15000L;

			return timeout > int.MaxValue
				? int.MaxValue
				: (int)timeout;
		}
		
		private static Image DecodeBase64Image( string pictureBase64)
		{
			if (string.IsNullOrWhiteSpace( pictureBase64))
			{
				return null;
			}

			try
			{
				byte[] imageBytes = Convert.FromBase64String( pictureBase64);

				using (var stream = new MemoryStream(imageBytes))
				using (Image decoded = Image.FromStream( stream, useEmbeddedColorManagement: false, validateImageData: true))
				{
					/*
					 * Bitmap odpojí výsledok od MemoryStream.
					 */
					return new Bitmap(decoded);
				}
			}
			catch
			{
				return null;
			}
		}
		
		private static bool PayloadContainsImage( string payload)
		{
			if (string.IsNullOrWhiteSpace(payload))
			{
				return false;
			}

			return payload.IndexOf( "\"pictureBase64\"", StringComparison.OrdinalIgnoreCase) >= 0;
		}
		
		private static DateTimeOffset? ParseFrameTime( string value)
		{
			if (string.IsNullOrWhiteSpace(value))
			{
				return null;
			}

			DateTimeOffset parsed;

			if (DateTimeOffset.TryParse(
				    value,
				    System.Globalization.CultureInfo.InvariantCulture,
				    System.Globalization.DateTimeStyles.RoundtripKind,
				    out parsed))
			{
				return parsed;
			}

			return null;
		}
		
		private static void TryLogSendSummary( string payload, int cameraIdx)
		{
			try
			{
				SendSummaryPayload summary = JsonConvert.DeserializeObject<SendSummaryPayload>(payload);

				if (summary == null)
				{
					return;
				}

				log.Debug( $"Send summary received: cameraIdx={cameraIdx}, picCount={summary.PictureCount}, " +
					$"delay={summary.Delay}, timeStamp={summary.TimeStamp}");
			}
			catch (Exception exc)
			{
				log.Debug( $"Payload is not a send summary: cameraIdx={cameraIdx}, error={exc.Message}");
			}
		}
		
		

	}
}