///////////////////////////////////////////////////////////////////////////////
/// \class OscProb::PremModel
///
/// \brief Implements an earth model with spherical shells
///
/// This class implements a spherically symmetric model of the earth
/// using PremLayer's to store spherical shells with different properties.
///
/// The class is then able to produce path sequences through the different
/// earth layers as a function of the cosine of the zenith angle with
/// respect to the detector.
///
/// The detector can be positioned at any radius within the model and
/// the path sequences will take into account the fact that some layers
/// are above the detector.
///
/// By default this implements the model stored in PremTables/prem_default.txt
/// with the detector at the bottom of the ocean layer (radius = 6368 km).
///
/// This class inherits from EarthModelBase and can be saved in ROOT files.
///
/// \author jcoelho\@apc.in2p3.fr
///////////////////////////////////////////////////////////////////////////////

#ifndef PREMMODEL_H
#define PREMMODEL_H

#include "Definitions.h"
#include "EarthModelBase.h"

namespace OscProb {

  class PremModel : public EarthModelBase {
    public:
      PremModel(std::string filename = ""); ///< Constructor
      virtual ~PremModel();                 ///< Destructor

      void SetDetPos(double rad, double lat = 0,
                     double lon = 0); ///< Set the detector position (rad =
                                      ///< radius in km, lat/lon in deg)

      int FillPath(double cosT,
                   double phi = 0); ///< Fill the path sequence in a vector

      virtual void LoadModel(
          std::string filename); ///< Load an earth model from a file

      virtual std::vector<PremLayer> GetPremLayers(); ///< Get the set of earth
                                                      ///< layers

      virtual void SetLayerZoA(
          int layer, double zoa); ///< Set Z/A of all layers of a given type
      virtual double GetLayerZoA(
          int layer); ///< Get Z/A of all layers of a given type

      virtual void SetTopLayerSize(
          double thick); ///< Set the outermost layer thickness in km

    protected:
      virtual void ClearModel(); ///< Clear the earth model information

      virtual void AddLayer(double radius, double density, double zoa,
                            double layer); ///< Add a layer to the model

      virtual void AddPath(
          double length, PremLayer pl); ///< Add a path segment to the sequence

      virtual void AddDetLayer();    ///< Add the detector layer
      virtual void CleanIdentical(); ///< Clear identical consecutive layers

      std::vector<PremLayer> fPremLayers; ///< The layers in the earth model

      int fDetLayer; ///< The layer index of the detector

      std::string fFilename; ///< The input filename

      static const double
          DET_TOL; ///< The detector position tolerance near boundaries

      // Required for saving in ROOT files
      ClassDef(PremModel, 1);
  };

} // namespace OscProb

#endif