/* -------------------------------------------------------------------------
 * BKG NTRIP Client
 * -------------------------------------------------------------------------
 *
 * Class:      t_pppSatObs
 *
 * Purpose:    Satellite observations
 *
 * Author:     L. Mervart
 *
 * Created:    29-Jul-2014
 *
 * Changes:
 *
 * -----------------------------------------------------------------------*/


#include <iostream>
#include <cmath>
#include <newmatio.h>

#include "pppSatObs.h"
#include "bncconst.h"
#include "pppEphPool.h"
#include "pppStation.h"
#include "bncutils.h"
#include "bncantex.h"
#include "pppObsPool.h"
#include "pppClient.h"

using namespace BNC_PPP;
using namespace std;

// Constructor
////////////////////////////////////////////////////////////////////////////
t_pppSatObs::t_pppSatObs(const t_satObs& pppSatObs) {
  _prn     = pppSatObs._prn;
  _time    = pppSatObs._time;
  _outlier = false;
  _valid   = true;
  for (unsigned ii = 0; ii < t_frequency::max; ii++) {
    _obs[ii] = 0;
  }
  prepareObs(pppSatObs);
}

// Destructor
////////////////////////////////////////////////////////////////////////////
t_pppSatObs::~t_pppSatObs() {
  for (unsigned iFreq = 1; iFreq < t_frequency::max; iFreq++) {
    delete _obs[iFreq];
  }
}

//
////////////////////////////////////////////////////////////////////////////
void t_pppSatObs::prepareObs(const t_satObs& pppSatObs) {

  _model.reset();

  // Select pseudoranges and phase observations
  // ------------------------------------------
  const string preferredAttrib = "CWPXI_";

  for (unsigned iFreq = 1; iFreq < t_frequency::max; iFreq++) {
    string frqNum = t_frequency::toString(t_frequency::type(iFreq)).substr(1);
    for (unsigned iPref = 0; iPref < preferredAttrib.length(); iPref++) {
      string obsType = (preferredAttrib[iPref] == '_') ? frqNum : frqNum + preferredAttrib[iPref];
      if (_obs[iFreq] == 0) {
        for (unsigned ii = 0; ii < pppSatObs._obs.size(); ii++) {
          const t_frqObs* obs = pppSatObs._obs[ii];
          if (obs->_rnxType2ch == obsType &&
              obs->_codeValid && obs->_code &&
              obs->_phaseValid && obs->_phase) {
            _obs[iFreq] = new t_frqObs(*obs);
          }
        }
      }
    }
  }

  // Used frequency types
  // --------------------
  _fType1 = t_lc::toFreq(_prn.system(),t_lc::l1);
  _fType2 = t_lc::toFreq(_prn.system(),t_lc::l2);

  // Check whether all required frequencies available
  // ------------------------------------------------
  for (unsigned ii = 0; ii < OPT->LCs(_prn.system()).size(); ii++) {
    t_lc::type tLC = OPT->LCs(_prn.system())[ii];
    if (!isValid(tLC)) {
      _valid = false;
      return;
    }
  }

  // Find Glonass Channel Number
  // ---------------------------
  if (_prn.system() == 'R') {
    _channel = PPP_CLIENT->ephPool()->getChannel(_prn);
  }
  else {
    _channel = 0;
  }

  // Compute Satellite Coordinates at Time of Transmission
  // -----------------------------------------------------
  _xcSat.ReSize(4); _xcSat = 0.0;
  _vvSat.ReSize(4); _vvSat = 0.0;
  bool totOK  = false;
  ColumnVector satPosOld(4); satPosOld = 0.0;
  t_lc::type tLC = isValid(t_lc::cIF) ? t_lc::cIF : t_lc::c1;
  double prange = obsValue(tLC);
  for (int ii = 1; ii <= 10; ii++) {
    bncTime ToT = _time - prange / t_CST::c - _xcSat[3];
    if (PPP_CLIENT->ephPool()->getCrd(_prn, ToT, _xcSat, _vvSat) != success) {
      _valid = false;
      return;
    }
    ColumnVector dx = _xcSat - satPosOld;
    dx[3] *= t_CST::c;
    if (dx.norm_Frobenius() < 1.e-4) {
      totOK = true;
      break;
    }
    satPosOld = _xcSat;
  }
  if (totOK) {
    _signalPropagationTime = prange / t_CST::c - _xcSat[3];
    _model._satClkM = _xcSat[3] * t_CST::c;
  }
  else {
    _valid = false;
  }
}

//
////////////////////////////////////////////////////////////////////////////
void t_pppSatObs::lcCoeff(t_lc::type tLC,
                          map<t_frequency::type, double>& codeCoeff,
                          map<t_frequency::type, double>& phaseCoeff) const {

  codeCoeff.clear();
  phaseCoeff.clear();

  double f1 = t_CST::freq(_fType1, _channel);
  double f2 = t_CST::freq(_fType2, _channel);

  switch (tLC) {
  case t_lc::l1:
    phaseCoeff[_fType1] = 1.0;
    return;
  case t_lc::l2:
    phaseCoeff[_fType2] = 1.0;
    return;
  case t_lc::lIF:
    phaseCoeff[_fType1] =  f1 * f1 / (f1 * f1 - f2 * f2);
    phaseCoeff[_fType2] = -f2 * f2 / (f1 * f1 - f2 * f2);
    return;
  case t_lc::MW:
    phaseCoeff[_fType1] =  f1 / (f1 - f2);
    phaseCoeff[_fType2] = -f2 / (f1 - f2);
    codeCoeff[_fType1]  = -f1 / (f1 + f2);
    codeCoeff[_fType2]  = -f2 / (f1 + f2);
    return;
  case t_lc::CL:
    phaseCoeff[_fType1] =  0.5;
    codeCoeff[_fType1]  =  0.5;
    return;
  case t_lc::c1:
    codeCoeff[_fType1] = 1.0;
    return;
  case t_lc::c2:
    codeCoeff[_fType2] = 1.0;
    return;
  case t_lc::cIF:
    codeCoeff[_fType1] =  f1 * f1 / (f1 * f1 - f2 * f2);
    codeCoeff[_fType2] = -f2 * f2 / (f1 * f1 - f2 * f2);
    return;
  case t_lc::dummy:
  case t_lc::maxLc:
    return;
  }
}

//
////////////////////////////////////////////////////////////////////////////
bool t_pppSatObs::isValid(t_lc::type tLC) const {
  bool valid = true;
  obsValue(tLC, &valid);
  return valid;
}
//
////////////////////////////////////////////////////////////////////////////
double t_pppSatObs::obsValue(t_lc::type tLC, bool* valid) const {

  map<t_frequency::type, double> codeCoeff;
  map<t_frequency::type, double> phaseCoeff;
  lcCoeff(tLC, codeCoeff, phaseCoeff);

  double retVal = 0.0;
  if (valid) *valid = true;

  map<t_frequency::type, double>::const_iterator it;
  for (it = codeCoeff.begin(); it != codeCoeff.end(); it++) {
    t_frequency::type tFreq = it->first;
    if (_obs[tFreq] == 0) {
      if (valid) *valid = false;
      return 0.0;
    }
    else {
      retVal += it->second * _obs[tFreq]->_code;
    }
  }
  for (it = phaseCoeff.begin(); it != phaseCoeff.end(); it++) {
    t_frequency::type tFreq = it->first;
    if (_obs[tFreq] == 0) {
      if (valid) *valid = false;
      return 0.0;
    }
    else {
      retVal += it->second * _obs[tFreq]->_phase * t_CST::lambda(tFreq, _channel);
    }
  }

  return retVal;
}

//
////////////////////////////////////////////////////////////////////////////
double t_pppSatObs::lambda(t_lc::type tLC) const {

  double f1 = t_CST::freq(_fType1, _channel);
  double f2 = t_CST::freq(_fType2, _channel);

  if      (tLC == t_lc::l1) {
    return t_CST::c / f1;
  }
  else if (tLC == t_lc::l2) {
    return t_CST::c / f2;
  }
  else if (tLC == t_lc::lIF) {
    return t_CST::c / (f1 + f2);
  }
  else if (tLC == t_lc::MW) {
    return t_CST::c / (f1 - f2);
  }
  else if (tLC == t_lc::CL) {
    return t_CST::c / f1 / 2.0;
  }

  return 0.0;
}

//
////////////////////////////////////////////////////////////////////////////
double t_pppSatObs::sigma(t_lc::type tLC) const {

  map<t_frequency::type, double> codeCoeff;
  map<t_frequency::type, double> phaseCoeff;
  lcCoeff(tLC, codeCoeff, phaseCoeff);

  double retVal = 0.0;

  map<t_frequency::type, double>::const_iterator it;
  for (it = codeCoeff.begin(); it != codeCoeff.end(); it++) {
    retVal += it->second * it->second * OPT->_sigmaC1 * OPT->_sigmaC1;
  }
  for (it = phaseCoeff.begin(); it != phaseCoeff.end(); it++) {
    retVal += it->second * it->second * OPT->_sigmaL1 * OPT->_sigmaL1;
  }

  retVal = sqrt(retVal);

  // De-Weight GLONASS
  // -----------------
  if (_prn.system() == 'R') {
    retVal *= 5.0;
  }

  // Elevation-Dependent Weighting
  // -----------------------------
  double cEle = 1.0;
  if ( (OPT->_eleWgtCode  && t_lc::includesCode(tLC)) ||
       (OPT->_eleWgtPhase && t_lc::includesPhase(tLC)) ) {
    double eleD = eleSat()*180.0/M_PI;
    double hlp  = fabs(90.0 - eleD);
    cEle = (1.0 + hlp*hlp*hlp*0.000004);
  }

  return cEle * retVal;
}

//
////////////////////////////////////////////////////////////////////////////
double t_pppSatObs::maxRes(t_lc::type tLC) const {

  map<t_frequency::type, double> codeCoeff;
  map<t_frequency::type, double> phaseCoeff;
  lcCoeff(tLC, codeCoeff, phaseCoeff);

  double retVal = 0.0;

  map<t_frequency::type, double>::const_iterator it;
  for (it = codeCoeff.begin(); it != codeCoeff.end(); it++) {
    retVal += it->second * it->second * OPT->_maxResC1 * OPT->_maxResC1;
  }
  for (it = phaseCoeff.begin(); it != phaseCoeff.end(); it++) {
    retVal += it->second * it->second * OPT->_maxResL1 * OPT->_maxResL1;
  }

  return sqrt(retVal);
}


//
////////////////////////////////////////////////////////////////////////////
t_irc t_pppSatObs::cmpModel(const t_pppStation* station) {

  // Reset all model values
  // ----------------------
  _model.reset();

  // Topocentric Satellite Position
  // ------------------------------
  ColumnVector rSat = _xcSat.Rows(1,3);
  ColumnVector rhoV = rSat - station->xyzApr();
  _model._rho = rhoV.norm_Frobenius();

  ColumnVector neu(3);
  xyz2neu(station->ellApr().data(), rhoV.data(), neu.data());

  _model._eleSat = acos( sqrt(neu[0]*neu[0] + neu[1]*neu[1]) / _model._rho );
  if (neu[2] < 0) {
    _model._eleSat *= -1.0;
  }
  _model._azSat  = atan2(neu[1], neu[0]);

  // Satellite Clocks
  // ----------------
  _model._satClkM = _xcSat[3] * t_CST::c;

  // Receiver Clocks
  // ---------------
  _model._recClkM = station->dClk() * t_CST::c;

  // Sagnac Effect (correction due to Earth rotation)
  // ------------------------------------------------
  ColumnVector Omega(3);
  Omega[0] = 0.0;
  Omega[1] = 0.0;
  Omega[2] = t_CST::omega / t_CST::c;
  _model._sagnac = DotProduct(Omega, crossproduct(rSat, station->xyzApr()));

  // Antenna Eccentricity
  // --------------------
  _model._antEcc = -DotProduct(station->xyzEcc(), rhoV) / _model._rho;

  // Antenna Phase Center Offsets and Variations
  // -------------------------------------------
  if (PPP_CLIENT->antex()) {
    for (unsigned ii = 0; ii < t_frequency::max; ii++) {
      t_frequency::type frqType = static_cast<t_frequency::type>(ii);
      bool found;
      _model._antPCO[ii] = PPP_CLIENT->antex()->rcvCorr(station->antName(), frqType,
                                                        _model._eleSat, _model._azSat, found);
    }
  }

  // Tropospheric Delay
  // ------------------
  _model._tropo = t_tropo::delay_saast(station->xyzApr(), _model._eleSat);

  // Phase Wind-Up
  // -------------
  _model._windUp = station->windUp(_time, _prn, rSat);

  // Code Biases
  // -----------
  const t_satCodeBias* satCodeBias = PPP_CLIENT->obsPool()->satCodeBias(_prn);
  if (satCodeBias) {
    for (unsigned ii = 0; ii < satCodeBias->_bias.size(); ii++) {
      const t_frqCodeBias& bias = satCodeBias->_bias[ii];
      for (unsigned iFreq = 1; iFreq < t_frequency::max; iFreq++) {
        const t_frqObs* obs = _obs[iFreq];
        if (obs && obs->_rnxType2ch == bias._rnxType2ch) {
          _model._codeBias[iFreq]  = bias._value;
        }
      }
    }
  }

  // Phase Biases
  // -----------
  // TODO: consideration of fix indicators, yaw angle and jump counter
  const t_satPhaseBias* satPhaseBias = PPP_CLIENT->obsPool()->satPhaseBias(_prn);
  if (satPhaseBias) {
    for (unsigned ii = 0; ii < satPhaseBias->_bias.size(); ii++) {
      const t_frqPhaseBias& bias = satPhaseBias->_bias[ii];
      for (unsigned iFreq = 1; iFreq < t_frequency::max; iFreq++) {
        const t_frqObs* obs = _obs[iFreq];
        if (obs && obs->_rnxType2ch == bias._rnxType2ch) {
          _model._phaseBias[iFreq]  = bias._value;
        }
      }
    }
  }

  // Tidal Correction
  // ----------------
  _model._tide = -DotProduct(station->tideDspl(), rhoV) / _model._rho;

  // Ionospheric Delay
  // -----------------
  const t_vTec* vTec = PPP_CLIENT->obsPool()->vTec();
  bool vTecUsage = true;
  for (unsigned ii = 0; ii < OPT->LCs(_prn.system()).size(); ii++) {
    t_lc::type tLC = OPT->LCs(_prn.system())[ii];
    if (tLC == t_lc::cIF || tLC == t_lc::lIF) {
      vTecUsage = false;
    }
  }
  if (vTecUsage && vTec) {
    double stec = station->stec(vTec, _signalPropagationTime, rSat);
    for (unsigned iFreq = 1; iFreq < t_frequency::max; iFreq++) {
      t_frequency::type frqType = static_cast<t_frequency::type>(iFreq);
      _model._ionoCodeDelay[iFreq] = 40.3E16 / pow(t_CST::freq(frqType, _channel), 2) * stec;
    }
  }

  // Ocean Loading
  // -------------
  // TODO

  // Set Model Set Flag
  // ------------------
  _model._set = true;

  //printModel();

  return success;
}

//
////////////////////////////////////////////////////////////////////////////
void t_pppSatObs::printModel() const {

  LOG.setf(ios::fixed);
  LOG << "MODEL for Satellite " << _prn.toString() << endl
      << "RHO:        " << setw(12) << setprecision(3) << _model._rho     << endl
      << "ELE:        " << setw(12) << setprecision(3) << _model._eleSat * 180.0 / M_PI << endl
      << "AZI:        " << setw(12) << setprecision(3) << _model._azSat  * 180.0 / M_PI << endl
      << "SATCLK:     " << setw(12) << setprecision(3) << _model._satClkM << endl
      << "RECCLK:     " << setw(12) << setprecision(3) << _model._recClkM << endl
      << "SAGNAC:     " << setw(12) << setprecision(3) << _model._sagnac  << endl
      << "ANTECC:     " << setw(12) << setprecision(3) << _model._antEcc  << endl
      << "TROPO:      " << setw(12) << setprecision(3) << _model._tropo   << endl
      << "WINDUP:     " << setw(12) << setprecision(3) << _model._windUp  << endl
      << "TIDES:      " << setw(12) << setprecision(3) << _model._tide    << endl;
  for (unsigned iFreq = 1; iFreq < t_frequency::max; iFreq++) {
    if (_obs[iFreq]) {
      string frqStr = t_frequency::toString(t_frequency::type(iFreq));
      if (_prn.system() == frqStr[0]) {
      LOG << "PCO           : " << frqStr << setw(12) << setprecision(3) << _model._antPCO[iFreq]    << endl
          << "BIAS CODE     : " << frqStr << setw(12) << setprecision(3) << _model._codeBias[iFreq]  << endl
          << "BIAS PHASE    : " << frqStr << setw(12) << setprecision(3) << _model._phaseBias[iFreq]  << endl
          << "IONO CODEDELAY: " << frqStr << setw(12) << setprecision(3) << _model._ionoCodeDelay[iFreq] << endl;
      }
    }
  }
  for (unsigned ii = 0; ii < OPT->LCs(_prn.system()).size(); ii++) {
    t_lc::type tLC = OPT->LCs(_prn.system())[ii];
    LOG << "OBS-CMP " << t_lc::toString(tLC) << ": " << _prn.toString() << " "
        << setw(12) << setprecision(3) << obsValue(tLC) << " "
        << setw(12) << setprecision(3) << cmpValue(tLC) << " "
        << setw(12) << setprecision(3) << obsValue(tLC) - cmpValue(tLC) << endl;

  }
  LOG << "OBS-CMP MW: " << _prn.toString() << " "
      << setw(12) << setprecision(3) << obsValue(t_lc::MW) << " "
      << setw(12) << setprecision(3) << cmpValue(t_lc::MW) << " "
      << setw(12) << setprecision(3) << obsValue(t_lc::MW) - cmpValue(t_lc::MW) << endl;
}

//
////////////////////////////////////////////////////////////////////////////
double t_pppSatObs::cmpValueForBanc(t_lc::type tLC) const {
  return cmpValue(tLC) - _model._rho - _model._sagnac - _model._recClkM;
}

//
////////////////////////////////////////////////////////////////////////////
double t_pppSatObs::cmpValue(t_lc::type tLC) const {

  if (!isValid(tLC)) {
    return 0.0;
  }

  // Non-Dispersive Part
  // -------------------
  double nonDisp = _model._rho    + _model._recClkM - _model._satClkM
                 + _model._sagnac + _model._antEcc  + _model._tropo
                 + _model._tide;

  // Add Dispersive Part
  // -------------------
  map<t_frequency::type, double> codeCoeff;
  map<t_frequency::type, double> phaseCoeff;
  lcCoeff(tLC, codeCoeff, phaseCoeff);

  double dispPart = 0.0;

  map<t_frequency::type, double>::const_iterator it;
  for (it = codeCoeff.begin(); it != codeCoeff.end(); it++) {
    t_frequency::type tFreq = it->first;
    dispPart += it->second * (_model._antPCO[tFreq] - _model._codeBias[tFreq] +
                              _model._ionoCodeDelay[tFreq]);
  }
  for (it = phaseCoeff.begin(); it != phaseCoeff.end(); it++) {
    t_frequency::type tFreq = it->first;
    dispPart += it->second * (_model._antPCO[tFreq] - _model._phaseBias[tFreq] +
                              _model._windUp * t_CST::lambda(tFreq, _channel)  -
                              _model._ionoCodeDelay[tFreq]);
  }

    return nonDisp + dispPart;
}

//
////////////////////////////////////////////////////////////////////////////
void t_pppSatObs::setRes(t_lc::type tLC, double res) {
  _res[tLC] = res;
}

//
////////////////////////////////////////////////////////////////////////////
double t_pppSatObs::getRes(t_lc::type tLC) const {
  map<t_lc::type, double>::const_iterator it = _res.find(tLC);
  if (it != _res.end()) {
    return it->second;
  }
  else {
    return 0.0;
  }
}