/*
 * This file is part of the Owl Positioning System (OwlPS).
 * OwlPS is a project of the University of Franche-Comté
 * (Université de Franche-Comté), France.
 */


#include "frbhmbasic.hh"



Result FRBHMBasic::compute(const Request &_request)
{
  request = &_request ;

  // Select the closest point in SS
  closest_in_ss = &select_point(_request) ;

  compute_ap_distance_circles() ;
  Point3D position(multilaterate_2d(closest_in_ss->get_z())) ;

  return Result(request, name, position) ;
}


/* TODO:
 * It is ugly to duplicate this function from FBCM. We should find a
 * trick to do it prettier. The thing is that FBCM::estimate_distance()
 * will not call FRBHMBasic::friis_index() but FBCM::friis_index(),
 * which is wrong in our case.
 */
float FRBHMBasic::estimate_distance(const Measurement &measurement)
{
  double constant_term = make_constant_term(measurement) ;
  const float &average_ss = measurement.get_average_ss() ;
  const AccessPoint *ap = measurement.get_ap() ;
  return pow(10, (constant_term - average_ss) /
             (10 * friis_index(ap))) ;
}


inline float FRBHMBasic::friis_index(const AccessPoint *const ap) const
{
  return closest_in_ss->friis_index_for_ap(ap->get_mac_addr()) ;
}