using Sick.Tim781s.Colab.Commands;
using Sick.Tim781s.Colab.Helpers;
using Sick.Tim781s.Colab.Interfaces;

namespace Sick.Tim781s.Colab;

/// <summary>
/// ColaB session manager for handling send, receive and process telegrams
/// </summary>
public sealed class ColaBSession : IDisposable
{
    private readonly ITcpClient _tcpClient;
    private readonly object _lock = new();
    private bool _disposed;

    public bool IsOpen
    {
        get
        {
            lock (_lock)
            {
                return _tcpClient.IsConnected;
            }
        }
    }

    public ColaBSession(ITcpClient tcpClient)
    {
        _tcpClient = tcpClient ?? throw new ArgumentNullException(nameof(tcpClient));
    }

    /// <summary>
    /// Opens the session (connects to scanner)
    /// </summary>
    public void Open(int timeoutMs = 5000)
    {
        if (_disposed)
            throw new ObjectDisposedException(nameof(ColaBSession));

        if (IsOpen)
            return;

        _tcpClient.Connect(timeoutMs);
    }

    /// <summary>
    /// Closes the session (disconnects from scanner)
    /// </summary>
    public void Close()
    {
        if (_disposed)
            return;

        _tcpClient.Disconnect();
    }

    /// <summary>
    /// Executes a command and waits for reply
    /// </summary>
    public void ExecuteCommand(IColaBCommand command, int timeoutMs = 5000)
    {
        if (_disposed)
            throw new ObjectDisposedException(nameof(ColaBSession));

        if (!IsOpen)
            throw new InvalidOperationException("Session is not open");

        // Create ColaB frame from command
        var commandData = command.GetCommandData();
        var frame = ColaBHelper.CreateFrame(commandData.Span);

        // Send frame
        _tcpClient.Send(frame);

        // Receive reply with retry logic
        byte[]? replyFrame = null;
        int retries = 3;
        for (int i = 0; i < retries; i++)
        {
            try
            {
                replyFrame = _tcpClient.Receive(timeoutMs);
                break;
            }
            catch (TimeoutException) when (i < retries - 1)
            {
                // Retry on timeout
                System.Threading.Thread.Sleep(100);
                continue;
            }
        }

        if (replyFrame == null || replyFrame.Length == 0)
        {
            throw new TimeoutException($"No reply received after {retries} attempts");
        }

        // Parse frame and extract command data
        if (ColaBHelper.TryParseFrame(replyFrame, out var replyData, out _))
        {
            // Process reply
            command.ProcessReply(replyData.ToArray());
        }
        else
        {
            throw new InvalidOperationException($"Failed to parse reply frame. Raw reply: {BitConverter.ToString(replyFrame.Take(64).ToArray())}");
        }
    }

    public void Dispose()
    {
        if (_disposed)
            return;

        Close();
        _disposed = true;
    }
}