namespace ZB.MOM.WW.OtOpcUa.Driver.Modbus;

/// <summary>
///     Raised when a Modbus transport has no live socket and cannot get one for this call: the one
///     in-gate connect attempt failed, the reconnect is inside its backoff window, or auto-reconnect is
///     disabled. It says the ENDPOINT is unreachable, so the driver fails the rest of the batch fast
///     instead of paying the same failure once per tag.
/// </summary>
/// <remarks>
///     Derives from <see cref="IOException"/> so every existing socket-level classifier
///     (<c>ModbusSocketLifecycle.IsSocketLevelFailure</c>, the driver's comms-fault mapping) treats it as
///     a communication failure without extra plumbing.
/// </remarks>
public sealed class ModbusTransportUnavailableException : IOException
{
    /// <summary>Initializes a new instance of the <see cref="ModbusTransportUnavailableException"/> class.</summary>
    /// <param name="message">A human-readable description.</param>
    /// <param name="inner">The originating exception, if any.</param>
    public ModbusTransportUnavailableException(string message, Exception? inner = null)
        : base(message, inner)
    {
    }
}