#ifndef PROPAGATION_LOSS_MODEL_H

#define PROPAGATION_LOSS_MODEL_H

#include "ns3/object.h"

namespace ns3 {

class RandomVariable;

class PropagationLossModel : public Object

{

public:

  virtual ~PropagationLossModel ();

  virtual double GetRxPower (double txPowerDbm,

			     double distance) const = 0;

  static Ptr<PropagationLossModel> CreateDefault (void);

};

class RandomPropagationLossModel : public PropagationLossModel

{

public:

  RandomPropagationLossModel ();

  RandomPropagationLossModel (const RandomVariable &variable);

  virtual ~RandomPropagationLossModel ();

  virtual double GetRxPower (double txPowerDbm,

			     double distance) const;

private:

  RandomVariable *m_variable;

};

class FriisPropagationLossModel : public PropagationLossModel

{

public:

  FriisPropagationLossModel ();

  void SetLambda (double frequency, double speed);

  void SetLambda (double lambda);

  void SetSystemLoss (double systemLoss);

  double GetLambda (void) const;

  double GetSystemLoss (void) const;

  virtual double GetRxPower (double txPowerDbm,

			     double distance) const;

private:

  double DbmToW (double dbm) const;

  double DbmFromW (double w) const;

  static const double PI;

  double m_lambda;

  double m_systemLoss;

};

class PathLossPropagationLossModel : public PropagationLossModel

{

public:

  PathLossPropagationLossModel ();

  void SetPathLossExponent (double n);

  double GetPathLossExponent (void) const;

  void SetReferenceModel (Ptr<PropagationLossModel> model);

  virtual double GetRxPower (double txPowerDbm,

			     double distance) const;

private:

  double DbToW (double db) const;

  static Ptr<PropagationLossModel> CreateDefaultReference (void);

  double m_exponent;

  Ptr<PropagationLossModel> m_reference;

};

} // namespace ns3

#endif /* PROPAGATION_LOSS_MODEL_H */