#ifndef __JACOUSTICS__JMECHANICS__
#define __JACOUSTICS__JMECHANICS__

#include <istream>
#include <ostream>
#include <fstream>
#include <iomanip>
#include <string>
#include <map>
#include <cmath>

#include "JSystem/JStat.hh"

#include "JLang/JStringStream.hh"
#include "JLang/JManip.hh"
#include "JLang/JException.hh"

#include "Jeep/JeepToolkit.hh"
#include "Jeep/JComment.hh"


/**
 * \file
 *
 * Mechanical modelling of string.
 * \author mdejong
 */
namespace JACOUSTICS {}
namespace JPP { using namespace JACOUSTICS; }

namespace JACOUSTICS {

  using JEEP::JComment;
  using JLANG::JFileOpenException;
 

  /**
   * Auxiliary data structure for parameters of mechanical model.\n
   * This data structure provides for the implementation of the effective height conform the mechanical model of string.
   */
  struct JMechanics {
    /**
     * Default constructor.
     */
    JMechanics() :
      a(0.0),
      b(0.0)
    {}


    /**
     * Constructor.
     *
     * \param  a                        logarithmic term
     * \param  b                        linear      term
     */
    JMechanics(const double a,
	       const double b) :
      a(a),
      b(b)
    {}


    /**
     * Get effective height for given actual height.
     *
     * \param  height                   height
     * \return                          height
     */
    double getHeight(const double height) const
    {
      return height  +  this->b * log(1.0 - this->a * height);
    }


    /**
     * Read parameters from input stream.
     *
     * \param  in                       input stream
     * \param  parameters               parameters
     * \return                          input stream
     */
    friend inline std::istream& operator>>(std::istream& in, JMechanics& parameters)
    {
      return in >> parameters.a >> parameters.b;
    }


    /**
     * Write parameters to output stream.
     *
     * \param  out                      output stream
     * \param  parameters               parameters
     * \return                          output stream
     */
    friend inline std::ostream& operator<<(std::ostream& out, const JMechanics& parameters)
    {
      return out << FIXED(7,5) << parameters.a << ' '
		 << FIXED(7,3) << parameters.b;
    }

    double a;   //!< <tt>0 <= a < (maximal height)⁻1;</tt>    [m^-1]
    double b;   //!< <tt>0 <= b;</tt>                         [m]
  };


  /**
   * Auxiliary data structure for mechanical model parameters of strings in a given detector.
   *
   * Note that the JDetectorMechanics::WILD_CARD acts as default value for the string number.
   */
  struct JDetectorMechanics :
    public std::map<int, JMechanics>
  {
    enum {
      WILD_CARD = -1   //!< wild card for string number.
    };


    /**
     * Get file name with mechanical model parameters for given detector identifier.
     *
     * \param  id                      detector identifier
     * \return                         file name
     */
    static std::string getFilename(const int id)
    {
      return MAKE_STRING("mechanics_" << FILL(8,'0') << id << ".txt");
    }


    /**
     * Load mechanical model parameters from file.
     *
     * \param  file_name               file name
     */
    void load(const std::string& file_name)
    {
      std::ifstream in(file_name.c_str());

      if (!in) {
        THROW(JFileOpenException, "File not opened for reading: " << file_name);
      }

      in >> *this;

      in.close();
    }


    /**
     * Load mechanical model parameters for given detector identifier.
     *
     * \param  id                      detector identifier
     */
    void load(const int id)
    {
      load(getFilename(id));
    }


    /**
     * Get mechanical parameters for given string.
     *
     * \param  string                  string number
     * \return                         mechanical parameters
     */
    const JMechanics& operator()(const int string) const
    {
      static const JMechanics mechanics;

      const_iterator p;

      if      ((p = this->find(string))    != this->end())
	return p->second;
      else if ((p = this->find(WILD_CARD)) != this->end())
	return p->second;
      else
	return mechanics;
    }


    /**
     * Read detector mechanics from input.
     *
     * \param  in           input stream
     * \param  object       detector mechanics
     * \return              input stream
     */
    friend inline std::istream& operator>>(std::istream& in, JDetectorMechanics& object)
    {
      using namespace JPP;

      JStringStream is(in);

      if (getFileStatus(is.str().c_str())) {
        is.load();
      }

      object.clear();
      
      is >> object.comment;
      
      int        string;
      JMechanics mechanics;

      while (is >> string >> mechanics) {
	object[string] = mechanics;
      }

      return in;
    }


    /**
     * Write detector mechanics to output.
     *
     * \param  out          output stream
     * \param  object       detector mechanics
     * \return              output stream
     */
    friend inline std::ostream& operator<<(std::ostream& out, const JDetectorMechanics& object)
    {
      using namespace std;

      out << object.comment;
      
      for (JDetectorMechanics::const_iterator i = object.begin(); i != object.end(); ++i) {
	out << setw(4) << i->first << ' ' << i->second << endl;
      }

      return out;
    }

    JComment comment;
  };


  /**
   * Function object to get string mechanics.
   */
  static JDetectorMechanics getMechanics;
}

#endif