/*
 * 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 "fbcm.hh"
#include "stock.hh"
#include "configuration.hh"



Result FBCM::compute(const Request &_request)
{
  // If the autocalibration is activated, we have to regenerate the
  // Friis indexes each time we calculate a position
  if (Configuration::bool_value("positioning.generate-reference-points"))
    Stock::update_all_friis_indexes() ;
  return MultilaterationAlgorithm::compute(_request) ;
}


float FBCM::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 FBCM::friis_index(const AccessPoint *const ap) const
{
  return ap->get_friis_index() ;
}