/* -*-  Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2009 CTTC
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation;
 *
 * 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
 *
 * Author: Nicola Baldo <nbaldo@cttc.es>
 */

#ifndef SPECTRUM_PROPAGATION_LOSS_MODEL_H
#define SPECTRUM_PROPAGATION_LOSS_MODEL_H


#include <ns3/object.h>
#include <ns3/mobility-model.h>
#include <ns3/spectrum-value.h>

namespace ns3 {




/**
 * \brief spectrum-aware propagation loss model
 *
 * Interface for propagation loss models to be adopted when
 * transmissions are modeled with a power spectral density by means of
 * the SpectrumValue class.
 *
 */
class SpectrumPropagationLossModel : public Object
{
public:
  SpectrumPropagationLossModel ();
  virtual ~SpectrumPropagationLossModel ();

  static TypeId GetTypeId ();


  /**
   * used to chain various instances of SpectrumPropagationLossModel
   *
   * @param next
   */
  void SetNext (Ptr<SpectrumPropagationLossModel> next);

  /**
   * This method is to be called to calculate
   *
   * @param txPsd the SpectrumValue representing the power spectral
   * density of the transmission. Watt units are to be used for radio
   * communications, and Pascal units for acoustic communications
   * (e.g. underwater).
   *
   * @param a sender mobility
   * @param b receiver mobility
   *
   * @return set of values vs frequency representing the received
   * power in the same units used for the txPower parameter.
   */
  Ptr<SpectrumValue> CalcRxPowerSpectralDensity (Ptr<const SpectrumValue> txPsd,
                                                 Ptr<const MobilityModel> a,
                                                 Ptr<const MobilityModel> b) const;

protected:
  virtual void DoDispose ();
  

private:
  /**
   *
   *
   * @param txPsd set of values vs frequency representing the
   * transmission power. See SpectrumChannel for details.
   * @param a sender mobility
   * @param b receiver mobility
   *
   * @return set of values vs frequency representing the received
   * power in the same units used for the txPower parameter.
   */
  virtual Ptr<SpectrumValue> DoCalcRxPowerSpectralDensity (Ptr<const SpectrumValue> txPsd,
                                                           Ptr<const MobilityModel> a,
                                                           Ptr<const MobilityModel> b) const = 0;

  Ptr<SpectrumPropagationLossModel> m_next;
};






} // namespace ns3

#endif /* SPECTRUM_PROPAGATION_LOSS_MODEL_H */
