/*
 * This file is part of the Owl Positioning System (OwlPS).
 * OwlPS is a project of the University of Franche-Comte
 * (Université de Franche-Comté), France.
 *
 * Copyright © Université de Franche-Comté 2007-2012.
 *
 * Corresponding author: Matteo Cypriani <mcy@lm7.fr>
 *
 ***********************************************************************
 *
 * This software is governed by the CeCILL license under French law and
 * abiding by the rules of distribution of free software. You can use,
 * modify and/or redistribute the software under the terms of the CeCILL
 * license as circulated by CEA, CNRS and INRIA at the following URL:
 * http://www.cecill.info
 *
 * As a counterpart to the access to the source code and rights to copy,
 * modify and redistribute granted by the license, users are provided
 * only with a limited warranty and the software's authors, the holder
 * of the economic rights, and the successive licensors have only
 * limited liability.
 *
 * In this respect, the user's attention is drawn to the risks
 * associated with loading, using, modifying and/or developing or
 * reproducing the software by the user in light of its specific status
 * of free software, that may mean that it is complicated to manipulate,
 * and that also therefore means that it is reserved for developers and
 * experienced professionals having in-depth computer knowledge. Users
 * are therefore encouraged to load and test the software's suitability
 * as regards their requirements in conditions enabling the security of
 * their systems and/or data to be ensured and, more generally, to use
 * and operate it in the same conditions as regards security.
 *
 * The fact that you are presently reading this means that you have had
 * knowledge of the CeCILL license and that you accept its terms.
 *
 ***********************************************************************
 */


#ifndef _OWLPS_POSITIONING_AUTOCALIBRATION_HH_
#define _OWLPS_POSITIONING_AUTOCALIBRATION_HH_

class AccessPoint ;
class Point3D ;

#include "measurement.hh"

#include <vector>
#include <boost/tr1/unordered_map.hpp>

/**
 * The class Autocalibration contains the code used to generate single
 * reference points from the autocalibration measurements.
 */
class Autocalibration
{
private:
  struct ap
  {
    const AccessPoint *ap ;
    float weight ; // Weight of the AP in percents
    float angle ;
  } ;

  /// Current AP to generate a SS for
  std::tr1::unordered_map<std::string, AccessPoint>::const_iterator rx ;
  /// Angle P-RX-O, O being the origin of the trigonometric circle
  float origin_angle ;
  /// Selected transmitter APs
  std::vector<ap> ref_aps ;
  /// \brief Angles of the transmitter APs (before M on the trigonometric
  /// circle)
  /**
   * Note that the angles are stored in absolute value.
   */
  std::multimap<double,
      std::pair<double,
      std::tr1::unordered_map<
      std::string, AccessPoint>::const_iterator> >
      sorted_negative_angles ;
  /// Angles of the transmitter APs (after M on the trigonometric circle)
  std::multimap<double,
      std::pair<double,
      std::tr1::unordered_map<
      std::string, AccessPoint>::const_iterator> >
      sorted_positive_angles ;
  /// Characteristics of the virtual mobile
  double vmob_gain, vmob_pow ;
  /// Generated measurements' list
  std::tr1::unordered_map<std::string, Measurement> measurements ;

protected:
  /// Number of generated "virtual" mobiles
  static uint32_t nb_virtual_mobiles ;

  /// The coordinates of the reference point to generate
  const Point3D &point ;

  /// Generates the SSs for all the APs
  void generate_ss(void) ;
  /// Sorts the reference APs for a receiver AP
  void sort_reference_aps(void) ;
  /// Computes the weight of the selected AP(s)
  void weight_aps(void) ;
  void init_ap(
    std::map<double, std::pair<double, std::tr1::unordered_map<
    std::string, AccessPoint>::const_iterator> >::const_iterator s) ;
  /// Weights two APs according to their angles
  void weight_2_aps(void) ;
  /// Computes the SS of the virtual mobile
  void compute_ss(void) ;
  /// Computes a SS with several packets in it
  void compute_multi_packet_ss(void) ;
  /// Computes a SS with only one packet in it
  bool compute_single_packet_ss(pkt_id_t pkt_id) ;
  /// Computes a SS according to the weight of the AP
  double compute_weighted_ss(
    unsigned int ap_idx, pkt_id_t pkt_id, float point_dst) ;

public:
  Autocalibration(const Point3D &_point): point(_point) {}

  /// Generates a single reference point
  void generate_reference_point(void) ;
} ;

#endif // _OWLPS_POSITIONING_AUTOCALIBRATION_HH_