/**
  * Connection Handler for the serial connection to the sfm
  * $Id$
  * $HeadURL$
  * $Author$
  * Created by Philipp Dassow, NLST, 2018-01-29
  */

#include "connection_handler_tcp.h"

#include <QTimer>

#include "settings.h"

namespace TrainingAreaBaseOC
{

ConnectionHandlerTcp::ConnectionHandlerTcp()
  : m_timer(new QTimer(this))
  , m_logger(getLogger("ConnectionHandlerTcp"))
{
  m_timer->setInterval(5000);
  connect(m_timer, &QTimer::timeout, this, &ConnectionHandlerTcp::open);
}

ConnectionHandlerTcp::~ConnectionHandlerTcp()
{
  m_socket->close();

  delete m_socket;
}

bool ConnectionHandlerTcp::init()
{
  m_socket = new QTcpSocket();

  connect(m_socket, &QTcpSocket::readyRead, this, &ConnectionHandlerTcp::read);
  connect(m_socket, QOverload<QAbstractSocket::SocketError>::of(&QAbstractSocket::error), this, &ConnectionHandlerTcp::handleError);
  connect(m_socket, &QTcpSocket::disconnected, this, &ConnectionHandlerTcp::open);
  connect(m_socket, &QTcpSocket::disconnected, this, &ConnectionHandlerTcp::disconnectedFromEq);
  open();

  return true;
}

bool ConnectionHandlerTcp::send(const LtsUtils::SfmMessage &message)
{
  if (!m_socket)
    return false;

  if (!m_socket->isOpen())
  {
    ERROR_LOG(m_logger) << "Port is not opened!";
    return false;
  }

  QByteArray data = LtsUtils::byteStreamFromSfmMessage(message);

  DEBUG_LOG(m_logger) << "Sending frame: " << data.toHex(' ');

  const qint64 byteswritten = m_socket->write(data);

  if (byteswritten == -1)
  {
    ERROR_LOG(m_logger) << "Failed to write data to port " << m_socket->peerPort() << " error: " << m_socket->errorString();
    m_timer->start();
    return false;
  }
  else if (byteswritten != data.size())
  {
    ERROR_LOG(m_logger) << "Failed to write all data to port " << m_socket->peerPort() << " error: " << m_socket->errorString();
    return false;
  }

  return true;
}

bool ConnectionHandlerTcp::open()
{
  m_timer->stop();
  m_socket->connectToHost(Settings::hostName(), Settings::port());
  if (!m_socket->waitForConnected())
  {
    ERROR_LOG(m_logger) << "Could not (re)open tcp destination " << m_socket->peerName() << ":" << m_socket->peerPort() << ", error: " << m_socket->errorString();
    return false;
  }
  INFO_LOG(m_logger) << "(Re)openend tcp destination " << m_socket->peerName() << ":" <<  Settings::port();
  return true;
}

void ConnectionHandlerTcp::close()
{
  m_socket->close();
}

bool ConnectionHandlerTcp::isOpen() const
{
  return m_socket->isOpen();
}

void ConnectionHandlerTcp::read()
{
  const QByteArray ba = m_socket->readAll();
  m_currentDataRead.append(ba);

  DEBUG_LOG(m_logger) << "Binary data from sfm: " << ba.toHex(' ');

  int idxStart = -1;
  int idxEnd = -1;
  while ((idxStart = m_currentDataRead.indexOf(0x02)) >= 0 &&
         (idxEnd = m_currentDataRead.indexOf(0x03)) >= 0) // while complete message frame in buffer
  {
    QByteArray message = m_currentDataRead.mid(idxStart, (idxEnd - idxStart) + 1);

    LtsUtils::SfmMessage sfmMsg;
    DEBUG_LOG(m_logger) << "Frame from sfm as binary " << message.toHex();

    try
    {
      sfmMsg = LtsUtils::byteStreamToSfmMessage(message);
    }
    catch (const LtsUtils::ConversionError &ex)
    {
      ERROR_LOG(m_logger) << "Error converting QByteArray into LtsUtils::SfmMessage: " << ex.what();
      ERROR_LOG(m_logger) << "Faulty Data from sfm as binary " << message.toHex();
    }

    INFO_LOG(m_logger) << "Decoded message from sfm Id: " << sfmMsg.id() << " RTR: " << sfmMsg.rtr() << " Data: " << sfmMsg.payload().toHex();

    m_currentDataRead = m_currentDataRead.mid(idxEnd + 1);

    emit received(sfmMsg);
  }

  if (m_socket->bytesAvailable() > 0)
    DEBUG_LOG(m_logger) << "Still " << m_socket->bytesAvailable() << " available to be read";
}

void ConnectionHandlerTcp::handleError(QAbstractSocket::SocketError error)
{
  DEBUG_LOG(m_logger) << "Spontaneous error " << error << " doesn't have to be an error ...";

  const QString errStr(QStringLiteral("QTcpSocket::SocketError ") + QString::number(error) +
                       QStringLiteral(" from tcp port ") + QString::number(m_socket->peerPort()) +
                       QStringLiteral(" error: ") + m_socket->errorString());

  switch (error)
  {
  case QTcpSocket::SocketError::ConnectionRefusedError:
  case QTcpSocket::SocketError::SocketAccessError:
  case QTcpSocket::SocketError::SocketResourceError:
  {
    ERROR_LOG(m_logger) << "Closing port trying to reopen it.";
    close();
    m_timer->start();
    Q_FALLTHROUGH();
  }
  case QTcpSocket::SocketError::RemoteHostClosedError:
  {
    ERROR_LOG(m_logger) << "Host closed trying to reopen.";
    m_timer->start();
    break;
  }
  default:
  {
    ERROR_LOG(m_logger) << errStr;
    close();
    m_timer->start();
    break;
  }
  }
}

} // namespace TrainingAreaBaseOC