/**
  * Websocket interface to participant positions
  * $Id$
  * $HeadURL$
  * $Author$
  * Created by Justus Hertel, SLSE, 2020-07-08
  */

#include "web_socket_handler.h"

#include <QWebSocket>
#include <QJsonObject>
#include <QJsonDocument>

#include <ParticipantManagement/ppm.hpp>

namespace ParticipantManagement
{

WebSocketHandler::WebSocketHandler(QObject *parent)
  : QObject(parent)
  , m_webSocketServer(new QWebSocketServer(QStringLiteral("ParticipantPositionsSocket"), QWebSocketServer::NonSecureMode, this))
  , m_logger(getLogger(QStringLiteral("WebSocketHandler")))
{}

WebSocketHandler::~WebSocketHandler()
{
  for (const auto& ws : qAsConst(m_webSockets))
  {
    ws->disconnect(this);
  }
  m_webSockets.clear();
}

bool WebSocketHandler::init(quint16 listenPort)
{
  if (!m_webSocketServer->listen(QHostAddress::Any, listenPort))
  {
    WARNING_LOG(m_logger) << "Can not listen on port " << listenPort << " - aborting";
    return false;
  }

  connect(m_webSocketServer, &QWebSocketServer::newConnection,
          this, &WebSocketHandler::onNewConnection);

  INFO_LOG(m_logger) << "Listening on port " << m_webSocketServer->serverPort();
  return true;
}

bool WebSocketHandler::init(const QPair<quint16, quint16> &portRange)
{
  for (quint16 currentPort = portRange.first; currentPort <= portRange.second; ++currentPort)
  {
    if (init(currentPort))
      return true;
  }

  return init();
}

bool WebSocketHandler::sendTelegramInternal(const ParticipantPosition &pos, int eqNo) const
{
  QJsonObject obj;
  obj[QStringLiteral("participantId")]   = pos.participantId();
  obj[QStringLiteral("equipmentNumber")] = eqNo;
  obj[QStringLiteral("lat")]             = pos.pos().lat();
  obj[QStringLiteral("lon")]             = pos.pos().lon();
  obj[QStringLiteral("height")]          = pos.pos().z();

  const QString jsonStr = QString::fromUtf8(QJsonDocument(obj).toJson(QJsonDocument::Compact));

  bool ret = false;
  for (const auto &wsw : qAsConst(m_webSockets))
  {
    if (wsw->sendTextMessage(jsonStr))
      ret = true;
  }
  return ret;
}

void WebSocketHandler::onNewConnection()
{
  QWebSocket *ws = m_webSocketServer->nextPendingConnection();
  if (!ws)
    return;

  connect(ws, &QWebSocket::disconnected,
          this, &WebSocketHandler::onWebSocketDisconnected);

  m_webSockets += ws;

  INFO_LOG(m_logger) << "New websocket connected";
}

void WebSocketHandler::onWebSocketDisconnected()
{
  QWebSocket *ws = qobject_cast<QWebSocket *>(sender());
  if (!ws)
    return;

  m_webSockets.removeAll(ws);
  ws->deleteLater();

  INFO_LOG(m_logger) << "A websocket disconnected";
}

bool WebSocketHandler::sendPosition(const ParticipantPosition &participantPosition, int equipmentNumber) const
{
  if (!isConnected() || m_webSockets.isEmpty())
    return false;

  return sendTelegramInternal(participantPosition, equipmentNumber);
}

}