// Part of BNC, a utility for retrieving decoding and
// converting GNSS data streams from NTRIP broadcasters.
//
// Copyright (C) 2007
// German Federal Agency for Cartography and Geodesy (BKG)
// http://www.bkg.bund.de
// Czech Technical University Prague, Department of Geodesy
// http://www.fsv.cvut.cz
//
// Email: euref-ip@bkg.bund.de
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation, version 2.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

/* -------------------------------------------------------------------------
 * BKG NTRIP Client
 * -------------------------------------------------------------------------
 *
 * Class:      bncGetThread
 *
 * Purpose:    Thread that retrieves data from NTRIP caster
 *
 * Author:     L. Mervart
 *
 * Created:    24-Dec-2005
 *
 * Changes:    
 *
 * -----------------------------------------------------------------------*/

#include <stdlib.h>

#include <QFile>
#include <QTextStream>
#include <QtNetwork>
#include <QTime>

#include "bncgetthread.h"
#include "bnctabledlg.h"
#include "bncapp.h"
#include "bncutils.h"
#include "bncrinex.h"
#include "bnczerodecoder.h"

#include "RTCM/RTCM2Decoder.h"
#include "RTCM3/RTCM3Decoder.h"
#include "RTIGS/RTIGSDecoder.h"

using namespace std;

// Constructor
////////////////////////////////////////////////////////////////////////////
bncGetThread::bncGetThread(const QUrl& mountPoint, 
                           const QByteArray& format,
                           const QByteArray& latitude,
                           const QByteArray& longitude,
                           const QByteArray& nmea, int iMount) {

  setTerminationEnabled(true);

  _decoder    = 0;
  _mountPoint = mountPoint;
  _staID      = mountPoint.path().mid(1).toAscii();
  _staID_orig = _staID;
  _format     = format;
  _latitude   = latitude;
  _longitude  = longitude;
  _nmea       = nmea;
  _socket     = 0;
  _timeOut    = 20*1000;  // 20 seconds
  _nextSleep  =  1;       //  1 second
  _iMount     = iMount;   // index in mountpoints array

  // Check name conflict
  // -------------------
  QSettings settings;
  QListIterator<QString> it(settings.value("mountPoints").toStringList());
  int num = 0;
  int ind = -1;
  while (it.hasNext()) {
    ++ind;
    QStringList hlp = it.next().split(" ");
    if (hlp.size() <= 1) continue;
    QUrl url(hlp[0]);
    if (_mountPoint.path() == url.path()) {
      if (_iMount > ind) {
        ++num;
      }
    }
  }

  if (num > 0) {
    _staID = _staID.left(_staID.length()-1) + QString("%1").arg(num).toAscii();
  }    

  // Notice threshold
  // ----------------
  _inspSegm = 50;
  if ( settings.value("obsRate").toString().isEmpty() ) { _inspSegm = 0; }
  if ( settings.value("obsRate").toString().indexOf("5 Hz") != -1 ) { _inspSegm = 2; }
  if ( settings.value("obsRate").toString().indexOf("1 Hz") != -1 ) { _inspSegm = 10; }
  if ( settings.value("obsRate").toString().indexOf("0.5 Hz") != -1 ) { _inspSegm = 20; }
  if ( settings.value("obsRate").toString().indexOf("0.2 Hz") != -1 ) { _inspSegm = 40; }
  if ( settings.value("obsRate").toString().indexOf("0.1 Hz") != -1 ) { _inspSegm = 50; }
  _adviseFail = settings.value("adviseFail").toInt();
  _adviseReco = settings.value("adviseReco").toInt();
  _adviseScript = settings.value("adviseScript").toString();
  expandEnvVar(_adviseScript);

  // Latency interval/average
  // ------------------------
  _latIntr = 86400;
  if ( settings.value("latIntr").toString().isEmpty() ) { _latIntr = 0; }
  if ( settings.value("latIntr").toString().indexOf("1 min") != -1 ) { _latIntr = 60; }
  if ( settings.value("latIntr").toString().indexOf("5 min") != -1 ) { _latIntr = 300; }
  if ( settings.value("latIntr").toString().indexOf("15 min") != -1 ) { _latIntr = 900; }
  if ( settings.value("latIntr").toString().indexOf("1 hour") != -1 ) { _latIntr = 3600; }
  if ( settings.value("latIntr").toString().indexOf("6 hours") != -1 ) { _latIntr = 21600; }
  if ( settings.value("latIntr").toString().indexOf("1 day") != -1 ) { _latIntr = 86400; }

  // RINEX writer
  // ------------
  _samplingRate = settings.value("rnxSampl").toInt();
  if ( settings.value("rnxPath").toString().isEmpty() ) { 
    _rnx = 0;
  }
  else {
    _rnx = new bncRinex(_staID, mountPoint, format, latitude, longitude, nmea);
  }

  msleep(100); //sleep 0.1 sec
}

// Destructor
////////////////////////////////////////////////////////////////////////////
bncGetThread::~bncGetThread() {
  if (_socket) {
    _socket->close();
#if QT_VERSION == 0x040203
    delete _socket;
#else
    _socket->deleteLater();
#endif
  }
  delete _decoder;
  delete _rnx;    
}

#define AGENTVERSION "1.5"
// Connect to Caster, send the Request (static)
////////////////////////////////////////////////////////////////////////////
QTcpSocket* bncGetThread::request(const QUrl& mountPoint,
                                  QByteArray& latitude, QByteArray& longitude,
                                  QByteArray& nmea, int timeOut, 
                                  QString& msg) {

  // Connect the Socket
  // ------------------
  QSettings settings;
  QString proxyHost = settings.value("proxyHost").toString();
  int     proxyPort = settings.value("proxyPort").toInt();
 
  QTcpSocket* socket = new QTcpSocket();
  if ( proxyHost.isEmpty() ) {
    socket->connectToHost(mountPoint.host(), mountPoint.port());
  }
  else {
    socket->connectToHost(proxyHost, proxyPort);
  }
  if (!socket->waitForConnected(timeOut)) {
    msg += "Connect timeout\n";
    delete socket;
    return 0;
  }

  // Send Request
  // ------------
  QString uName = QUrl::fromPercentEncoding(mountPoint.userName().toAscii());
  QString passW = QUrl::fromPercentEncoding(mountPoint.password().toAscii());
  QByteArray userAndPwd;

  if(!uName.isEmpty() || !passW.isEmpty())
  {
    userAndPwd = "Authorization: Basic " + (uName.toAscii() + ":" +
    passW.toAscii()).toBase64() + "\r\n";
  }

  QUrl hlp;
  hlp.setScheme("http");
  hlp.setHost(mountPoint.host());
  hlp.setPort(mountPoint.port());
  hlp.setPath(mountPoint.path());

  QByteArray reqStr;
  if ( proxyHost.isEmpty() ) {
   if (hlp.path().indexOf("/") != 0) hlp.setPath("/");
     reqStr = "GET " + hlp.path().toAscii() + " HTTP/1.0\r\n";
   } else {
     reqStr = "GET " + hlp.toEncoded() + " HTTP/1.0\r\n";
  }
  reqStr += "User-Agent: NTRIP BNC/" AGENTVERSION "\r\n"
  "Host: " + hlp.host().toAscii() + "\r\n"
  + userAndPwd + "\r\n";

// NMEA string to handle VRS stream
// --------------------------------

  double lat, lon;

  lat = strtod(latitude,NULL);
  lon = strtod(longitude,NULL);

  if ((nmea == "yes") && (hlp.path().length() > 2) && (hlp.path().indexOf(".skl") < 0)) {
    const char* flagN="N";
    const char* flagE="E";
    if (lon >180.) {lon=(lon-360.)*(-1.); flagE="W";}
    if ((lon < 0.) && (lon >= -180.))  {lon=lon*(-1.); flagE="W";}
    if (lon < -180.)  {lon=(lon+360.); flagE="E";}
    if (lat < 0.)  {lat=lat*(-1.); flagN="S";}
    QTime ttime(QDateTime::currentDateTime().toUTC().time());
    int lat_deg = (int)lat;  
    double lat_min=(lat-lat_deg)*60.;
    int lon_deg = (int)lon;  
    double lon_min=(lon-lon_deg)*60.;
    int hh = 0 , mm = 0;
    double ss = 0.0;
    hh=ttime.hour();
    mm=ttime.minute();
    ss=(double)ttime.second()+0.001*ttime.msec();
    QString gga;
    gga += "GPGGA,";
    gga += QString("%1%2%3,").arg((int)hh, 2, 10, QLatin1Char('0')).arg((int)mm, 2, 10, QLatin1Char('0')).arg((int)ss, 2, 10, QLatin1Char('0'));
    gga += QString("%1%2,").arg((int)lat_deg,2, 10, QLatin1Char('0')).arg(lat_min, 7, 'f', 4, QLatin1Char('0'));
    gga += flagN;
    gga += QString(",%1%2,").arg((int)lon_deg,3, 10, QLatin1Char('0')).arg(lon_min, 7, 'f', 4, QLatin1Char('0'));
    gga += flagE + QString(",1,05,1.00,+00100,M,10.000,M,,");
    int xori;
    char XOR = 0;
    char *Buff =gga.toAscii().data();
    int iLen = strlen(Buff);
    for (xori = 0; xori < iLen; xori++) {
      XOR ^= (char)Buff[xori];
    }
    gga += QString("*%1").arg(XOR, 2, 16, QLatin1Char('0'));
    reqStr += "$";
    reqStr += gga;
    reqStr += "\r\n";
  }

  msg += reqStr;

  socket->write(reqStr, reqStr.length());

  if (!socket->waitForBytesWritten(timeOut)) {
    msg += "Write timeout\n";
    delete socket;
    return 0;
  }

  return socket;
}

// Init Run
////////////////////////////////////////////////////////////////////////////
t_irc bncGetThread::initRun() {

  // Initialize Socket
  // -----------------
  QString msg;
  _socket = this->request(_mountPoint, _latitude, _longitude, 
                          _nmea, _timeOut, msg);
  if (!_socket) {
    return failure;
  }

  // Read Caster Response
  // --------------------
  _socket->waitForReadyRead(_timeOut);
  if (_socket->canReadLine()) {
    QString line = _socket->readLine();

    // Skip messages from proxy server
    // -------------------------------
    if (line.indexOf("ICY 200 OK") == -1 && 
        line.indexOf("200 OK")     != -1 ) {
      bool proxyRespond = true;
      while (true) {
        if (_socket->canReadLine()) {
          line = _socket->readLine();
          if (!proxyRespond) {
            break;
          }
          if (line.trimmed().isEmpty()) {
            proxyRespond = false;
          }
        }
        else {
          _socket->waitForReadyRead(_timeOut);
          if (_socket->bytesAvailable() <= 0) {
            break;
          }
        }
      }
    }

    if (line.indexOf("Unauthorized") != -1) {
      QStringList table;
      bncTableDlg::getFullTable(_mountPoint.host(), _mountPoint.port(), table);
      QString net;
      QStringListIterator it(table);
      while (it.hasNext()) {
        QString line = it.next();
        if (line.indexOf("STR") == 0) {
          QStringList tags = line.split(";");
          if (tags.at(1) == _staID_orig) {
            net = tags.at(7);
            break;
          }
        }
      }

      QString reg;
      it.toFront();
      while (it.hasNext()) {
        QString line = it.next();
        if (line.indexOf("NET") == 0) {
          QStringList tags = line.split(";");
          if (tags.at(1) == net) {
            reg = tags.at(7);
            break;
          }          
        }
      }
      emit(newMessage((_staID + ": Caster Response: " + line + 
                       "          Adjust User-ID and Password Register, see"
                       "\n          " + reg).toAscii()));
      return fatal;
    }
    if (line.indexOf("ICY 200 OK") != 0) {
      emit(newMessage((_staID + ": Wrong Caster Response:\n" + line).toAscii()));
      return failure;
    }
  }
  else {
    emit(newMessage(_staID + ": Response Timeout"));
    return failure;
  }

  // Instantiate the filter
  // ----------------------
  if (!_decoder) { 
    if      (_format.indexOf("RTCM_2") != -1) {
      emit(newMessage("Get Data: " + _staID + " in RTCM 2.x format"));
      _decoder = new RTCM2Decoder();
    }
    else if (_format.indexOf("RTCM_3") != -1) {
      emit(newMessage("Get Data: " + _staID + " in RTCM 3.x format"));
      _decoder = new RTCM3Decoder();
    }
    else if (_format.indexOf("RTIGS") != -1) {
      emit(newMessage("Get Data: " + _staID + " in RTIGS format"));
      _decoder = new RTIGSDecoder();
    }
    else if (_format.indexOf("SP3") != -1 || _format.indexOf("ZERO") != -1) {
      emit(newMessage("Get Data: " + _staID + " in original format"));
      _decoder = new bncZeroDecoder(_staID);
    }
    else {
      emit(newMessage(_staID + ": Unknown data format " + _format));
      return fatal;
    }
  }
  return success;
}

// Run
////////////////////////////////////////////////////////////////////////////
void bncGetThread::run() {

  const double maxDt = 600.0;  // Check observation epoch
  bool wrongEpoch = false;
  bool decode = true;
  int numSucc = 0;
  int secSucc = 0;
  int secFail = 0;
  int initPause = 30;  // Initial pause for corrupted streams
  int currPause = 0;
  bool begCorrupt = false;
  bool endCorrupt = false;
  int oldSec= 0;
  int newSec = 0;
  int numLat = 0;
  double sumLat = 0.;
  double minLat = maxDt;
  double maxLat = -maxDt;
  double curLat = 0.;
  double leapsec = 14.;  // Leap second for latency estimation

  _decodeTime = QDateTime::currentDateTime();
  _decodeSucc = QDateTime::currentDateTime();
  t_irc irc = initRun();

  if      (irc == fatal) {
    QThread::exit(1);
    return;
  }
  else if (irc != success) {
    emit(newMessage(_staID + ": initRun failed, reconnecting"));
    tryReconnect();
  }

  if (initPause < _inspSegm) {
    initPause = _inspSegm;
  }
  currPause = initPause;

  // Read Incoming Data
  // ------------------
  while (true) {
    try {
      if (_socket->state() != QAbstractSocket::ConnectedState) {
        emit(newMessage(_staID + ": Socket not connected, reconnecting"));
        tryReconnect();
      }

      QListIterator<p_obs> it(_decoder->_obsList);
      while (it.hasNext()) {
        delete it.next();
      }
      _decoder->_obsList.clear();

      _socket->waitForReadyRead(_timeOut);
      qint64 nBytes = _socket->bytesAvailable();
      if (nBytes > 0) {
        emit newBytes(_staID, nBytes);

        char* data = new char[nBytes];
        _socket->read(data, nBytes);

      if (_inspSegm<1) {
        _decoder->Decode(data, nBytes);
      }
      else {

        // Decode data
        // -----------
        if (!_decodePause.isValid() || 
          _decodePause.secsTo(QDateTime::currentDateTime()) >= currPause )  {

          if (decode) { 
            if ( _decoder->Decode(data, nBytes) == success ) { 
              numSucc += 1;
            } 
            if ( _decodeTime.secsTo(QDateTime::currentDateTime()) > _inspSegm ) {
              decode = false;
            }
          }

          // Check - once per inspect segment
          // --------------------------------
          if (!decode) {
            _decodeTime = QDateTime::currentDateTime();
            if (numSucc>0) {
              secSucc += _inspSegm;
              _decodeSucc = QDateTime::currentDateTime();
              if (secSucc > _adviseReco * 60) {
                secSucc = _adviseReco * 60 + 1;
              }
              numSucc = 0;
              currPause = initPause;
              _decodePause.setDate(QDate());
              _decodePause.setTime(QTime());
            }
            else {
              secFail += _inspSegm;
              secSucc = 0;
              if (secFail > _adviseFail * 60) { 
                secFail = _adviseFail * 60 + 1;
              }
              if (!_decodePause.isValid()) {
                _decodePause = QDateTime::currentDateTime();
              }
              else {
                _decodePause.setDate(QDate());
                _decodePause.setTime(QTime());
                secFail = secFail + currPause - _inspSegm;
                currPause = currPause * 2;
                if (currPause > 960) {
                currPause = 960;
                }
              }
            }

            // End corrupt threshold
            // ---------------------
            if ( begCorrupt && !endCorrupt && secSucc > _adviseReco * 60 ) {
              _endDateCor = QDateTime::currentDateTime().addSecs(- _adviseReco * 60).toUTC().date().toString("yy-MM-dd");
              _endTimeCor = QDateTime::currentDateTime().addSecs(- _adviseReco * 60).toUTC().time().toString("hh:mm:ss");
              emit(newMessage((_staID + ": Recovery threshold exceeded, corruption ended " + _endDateCor + " " + _endTimeCor).toAscii()));
              callScript(("End_Corrupted " + _endDateCor + " " + _endTimeCor + " Begin was " + _begDateCor + " " + _begTimeCor).toAscii());
              endCorrupt = true;
              begCorrupt = false;
              secFail = 0;
            } 
            else {

              // Begin corrupt threshold
              // -----------------------
              if ( !begCorrupt && secFail > _adviseFail * 60 ) {
                _begDateCor = _decodeSucc.toUTC().date().toString("yy-MM-dd");
                _begTimeCor = _decodeSucc.toUTC().time().toString("hh:mm:ss");
                emit(newMessage((_staID + ": Failure threshold exceeded, corrupted since " + _begDateCor + " " + _begTimeCor).toAscii()));
                callScript(("Begin_Corrupted " + _begDateCor + " " + _begTimeCor).toAscii());
                begCorrupt = true;
                endCorrupt = false;
                secSucc = 0;
                numSucc = 0;
              }
            }
            decode = true;
          }
        }
      }

      // End outage threshold
      // --------------------
      if ( _decodeStart.isValid() && _decodeStart.secsTo(QDateTime::currentDateTime()) > _adviseReco * 60 ) {
        _decodeStart.setDate(QDate());
        _decodeStart.setTime(QTime());
        if (_inspSegm>0) {
          _endDateOut = QDateTime::currentDateTime().addSecs(- _adviseReco * 60).toUTC().date().toString("yy-MM-dd");
          _endTimeOut = QDateTime::currentDateTime().addSecs(- _adviseReco * 60).toUTC().time().toString("hh:mm:ss");
          emit(newMessage((_staID + ": Recovery threshold exceeded, outage ended " + _endDateOut + " " + _endTimeOut).toAscii()));
          callScript(("End_Outage " + _endDateOut + " " + _endTimeOut + " Begin was " + _begDateOut + " " + _begTimeOut).toAscii());
        }
      }

        delete [] data;
        
        QListIterator<p_obs> it(_decoder->_obsList);
        while (it.hasNext()) {
          p_obs obs = it.next();

          // Check observation epoch
          // -----------------------
          int    week;
          double sec;
          currentGPSWeeks(week, sec);
          
          const double secPerWeek = 7.0 * 24.0 * 3600.0;

          if (week < obs->_o.GPSWeek) {
            week += 1;
            sec  -= secPerWeek;
          }
          if (week > obs->_o.GPSWeek) {
            week -= 1;
            sec  += secPerWeek;
          }
          double dt = fabs(sec - obs->_o.GPSWeeks);
          if (week != obs->_o.GPSWeek || dt > maxDt) {
            if  (!wrongEpoch) {
              emit( newMessage(_staID + ": Wrong observation epoch") );
              wrongEpoch = true;
            }
            delete obs;
            continue;
          }
          else {
            wrongEpoch = false;

            // Latency
            // -------
            if (_latIntr>0) {
              newSec = static_cast<int>(sec);
              if (newSec != oldSec) {
                if (newSec % _latIntr < oldSec % _latIntr) {
                  if (numLat>0) {
                    emit( newMessage(QString("%1: %2 sec mean latency, min %3, max %4")
                      .arg(_staID.data())
                      .arg(int(sumLat/numLat*100)/100.)
                      .arg(int(minLat*100)/100.)
                      .arg(int(maxLat*100)/100.)
                      .toAscii()) );
                  }
                  sumLat = 0.;
                  numLat = 0;
                  minLat = maxDt;
                  maxLat = -maxDt;
                }
                curLat = sec - obs->_o.GPSWeeks + leapsec;
                sumLat += curLat;
                if (curLat < minLat) minLat = curLat;
                if (curLat >= maxLat) maxLat = curLat;
                numLat += 1;
                oldSec = newSec;
              }
            }
          }

          // RINEX Output
          // ------------
          if (_rnx) {
             long iSec    = long(floor(obs->_o.GPSWeeks+0.5));
             long newTime = obs->_o.GPSWeek * 7*24*3600 + iSec;
            if (_samplingRate == 0 || iSec % _samplingRate == 0) {
              _rnx->deepCopy(obs);
            }
            _rnx->dumpEpoch(newTime);
          }

          bool firstObs = (obs == _decoder->_obsList.first());
          obs->_status = t_obs::posted;
          emit newObs(_staID, firstObs, obs);
        }
        _decoder->_obsList.clear();
      }
      else {
        emit(newMessage(_staID + ": Data Timeout, reconnecting"));
        tryReconnect();
      }
    }
    catch (const char* msg) {
      emit(newMessage(_staID + msg));
      tryReconnect();
    }
  }
}

// Exit
////////////////////////////////////////////////////////////////////////////
void bncGetThread::exit(int exitCode) {
  if (exitCode!= 0) {
    emit error(_staID);
  }
  QThread::exit(exitCode);
  terminate();
}

// Try Re-Connect 
////////////////////////////////////////////////////////////////////////////
void bncGetThread::tryReconnect() {
  if (_rnx) {
    _rnx->setReconnectFlag(true);
  }
  if ( !_decodeStart.isValid()) {
    _decodeStop = QDateTime::currentDateTime();
  }
  while (1) {
    delete _socket; _socket = 0;
    sleep(_nextSleep);
    if ( initRun() == success ) {
      if ( !_decodeStop.isValid()) {
        _decodeStart = QDateTime::currentDateTime();
      }
      break;
    }
    else {

      // Begin outage threshold
      // ----------------------
      if ( _decodeStop.isValid() && _decodeStop.secsTo(QDateTime::currentDateTime()) > _adviseFail * 60 ) {
        _decodeStop.setDate(QDate());
        _decodeStop.setTime(QTime());
        if (_inspSegm>0) {
          _begDateOut = _decodeTime.toUTC().date().toString("yy-MM-dd");
          _begTimeOut = _decodeTime.toUTC().time().toString("hh:mm:ss");
          emit(newMessage((_staID + ": Failure threshold exceeded, outage since " + _begDateOut + " " + _begTimeOut).toAscii()));
          callScript(("Begin_Outage " + _begDateOut + " " + _begTimeOut).toAscii());
        }
      }
      _nextSleep *= 2;
      if (_nextSleep > 256) {
        _nextSleep = 256;
      }
      _nextSleep += rand() % 6;
    }
  }
  _nextSleep = 1;
}

// Call advisory notice script    
////////////////////////////////////////////////////////////////////////////
void bncGetThread::callScript(const char* _comment) {
  QMutexLocker locker(&_mutex);
  if (!_adviseScript.isEmpty()) {
    msleep(1);
#ifdef WIN32
    QProcess::startDetached(_adviseScript, QStringList() << _staID << _comment) ;
#else
    QProcess::startDetached("nohup", QStringList() << _adviseScript << _staID << _comment) ;
#endif
  }
}