#ifndef __JPHYSICS_JIONIZATION__
#define __JPHYSICS_JIONIZATION__

#include "JLang/JException.hh"

/**
 * \author vcarretero
 */

namespace JPHYSICS {}
namespace JPP { using namespace JPHYSICS; }

namespace JPHYSICS {

  using JLANG::JValueOutOfRange;

  /**
   * Struct for the Sternheimer coefficients.\n
   * Reference: R.M. Sternheimer, M.J. Berger, S.M. Seltzer. Density effect for the ionization loss of charged particles in various substances, Atomic Data and Nuclear Data Tables, Volume 30, Issue 2, 1984, Pages 261-271,ISSN 0092-640X, https://doi.org/10.1016/0092-640X(84)90002-0.
   */
  struct JSter {
    double I;          //!< Ionization potentian [GeV]
    double X0;         //!< Correction density parameter
    double X1;         //!< Correction density parameter
    double a;          //!< Correction density parameter
    double m;          //!< Correction density parameter
    double C;          //!< Correction density parameter  
  };


  /**
   * Auxiliary data structure Ster coefficients as a function of proton number.
   */
  struct JSterCoefficient :                                            
    public std::map<int, JSter>
  {
    /**
     * Default constructor.
     */     
    JSterCoefficient()
    {
      (*this)[ 1] = {  21.8e-9, 0.4400, 1.8856, 0.1348, 5.6249, -3.0977};  // H
      (*this)[ 8] = {  95.0e-9, 0.2868, 2.0000, 0.5223, 3.0000, -3.9471};  // O
      (*this)[11] = { 149.0e-9, 0.2880, 3.1962, 0.0777, 3.6452, -5.0526};  // Na
      (*this)[17] = { 174.0e-9, 0.2000, 3.0000, 0.1802, 3.0000, -4.8776};  // Cl
      (*this)[ 6] = {  78.0e-9,-0.0090, 2.4817, 0.2076, 2.9532, -2.8926};  // C
      (*this)[12] = { 156.0e-9, 0.1499, 3.0668, 0.0816, 3.6166, -4.5297};  // Mg
      (*this)[19] = { 190.0e-9, 0.3851, 3.1724, 0.1983, 2.9233, -5.6423};  // K
      (*this)[16] = { 180.0e-9, 0.1580, 2.7159, 0.3399, 2.6456, -4.6659};  // S
      (*this)[14] = { 173.0e-9, 0.2015, 2.8716, 0.1492, 3.2546, -4.4355};  // Si
      (*this)[13] = { 166.0e-9, 0.1708, 3.0127, 0.0802, 3.6345, -4.2395};  // Al
      (*this)[26] = { 286.0e-9,-0.0012, 3.1531, 0.1468, 2.9632, -4.2911};  // Fe
      (*this)[22] = { 233.0e-9, 0.0957, 3.0386, 0.1566, 3.0302, -4.4450};  // Ti 
      (*this)[20] = { 191.0e-9, 0.3228, 3.1191, 0.1564, 3.0745, -5.0396};  // Ca
      (*this)[35] = { 357.0e-9, 0.3669, 3.0000, 0.2211, 3.0000, -5.7268};  // Br
    }


    /**
     * Get Ster coefficients for given proton number.
     *
     * \param  Z        proton number
     * \return          Ster coefficients
     */
    const JSter& operator()(const int Z) const
    {
      const_iterator i = this->find(Z);

      if (i != this->end())
	return i->second;
      else
	THROW(JValueOutOfRange, "Invalid proton number " << Z);
    }
  };
    
  
  /**
   * Function object for Ster coefficients.
   */
  static JSterCoefficient getSterCoefficient;
}

#endif