/*
 * BondVectors.hpp
 *
 *  Created on: Jun 13, 2017
 *      Author: heber
 */


#ifndef DYNAMICS_BONDVECTORS_HPP_
#define DYNAMICS_BONDVECTORS_HPP_

// include config.h
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <map>
#include <vector>

#include "CodePatterns/Assert.hpp"

#include "LinearAlgebra/Vector.hpp"

#include "Bond/bond.hpp"

/** This class represents all bond vectors, i.e. the normalized direction
 * along a list of bonds, and provides means to extract them from a set of
 * atoms such that for an arbitrary bond the vector can be quickly retrieved.
 */
class BondVectors
{
public:
  //!> typedef for the internal container of the bonds
  typedef std::vector<bond::ptr> container_t;

  //!> typedef for the association of bonds to bond vectors
  typedef std::map<bond::ptr, Vector> mapped_t;

  /** Prepares the internal container from the bonds of a range of atoms.
   *
   * \param _start start of range
   * \param _end end of range
   * \param _step time step to request bonds for
   */
  template <class T>
  void setFromAtomRange(
      typename T::iterator _start,
      typename T::iterator _end,
      const size_t &_step);

  /** Getter for the sorted bonds.
   *
   * \return const ref to internal container
   */
  const container_t& getSorted() const
  {
    ASSERT( !container.empty(),
        "BondVectors::getSorted() - empty internal container, not set properly?");
    return container;
  }

  /** Calculates the bond vector for each bond in the internal container and
   * returns them in same order as the internal container.
   *
   * \param _step time step for which the bond vector is request
   * \return a map from bond to bond vector
   */
  mapped_t getBondVectorsAtStep(const size_t &_step) const;

  /** Get the position in the internal container for a specific bond.
   *
   * \param _bond given bond
   * \return position in the vector, -1 if not present
   */
  size_t getIndexForBond(const bond::ptr &_bond) const;

private:
  //!> internal container for sorted bonds
  container_t container;
};

#include "BondVectors_impl.hpp"

#endif /* DYNAMICS_BONDVECTORS_HPP_ */