//
//  Copyright (C) 2002-2006 Greg Landrum and Rational Discovery LLC
//
//   @@ All Rights Reserved @@
//  This file is part of the RDKit.
//  The contents are covered by the terms of the BSD license
//  which is included in the file license.txt, found at the root
//  of the RDKit source tree.
//
/*! \file BondIterators.h

  \brief various tools for iterating over a molecule's Bonds

   <b>WARNING:</b> If you go changing the molecule underneath one of
   these iterators you will be sad...
*/
#include <RDGeneral/export.h>
#ifndef _RD_BOND_ITERATORS_H
#define _RD_BOND_ITERATORS_H

#include "ROMol.h"

namespace RDKit {

//! \brief iterator for a molecule's bonds, currently BiDirectional,
//! but it theoretically ought to be RandomAccess.
class RDKIT_GRAPHMOL_EXPORT BondIterator_ {
  // FIX: I'm not pleased with the lack of internal testing code
  //  (PREs and the like) in here
 public:
  BondIterator_() {}
  BondIterator_(ROMol *mol);
  BondIterator_(ROMol *mol, ROMol::EDGE_ITER pos);
  BondIterator_(const BondIterator_ &other);
  BondIterator_ &operator=(const BondIterator_ &other);
  bool operator==(const BondIterator_ &other) const;
  bool operator!=(const BondIterator_ &other) const;
  Bond *operator*() const;
  // pre-increment
  BondIterator_ &operator++();
  BondIterator_ operator++(int);
  // pre-decrement
  BondIterator_ &operator--();
  BondIterator_ operator--(int);

 private:
  ROMol::EDGE_ITER _beg, _end, _pos;
  ROMol *_mol{nullptr};
};
//! \brief const iterator for a molecule's bonds, currently BiDirectional,
//! but it theoretically ought to be RandomAccess.
class RDKIT_GRAPHMOL_EXPORT ConstBondIterator_ {
 public:
  ConstBondIterator_() {}
  ConstBondIterator_(ROMol const *mol);
  ConstBondIterator_(ROMol const *mol, ROMol::EDGE_ITER pos);
  ConstBondIterator_(const ConstBondIterator_ &other);
  ConstBondIterator_ &operator=(const ConstBondIterator_ &other);
  bool operator==(const ConstBondIterator_ &other) const;
  bool operator!=(const ConstBondIterator_ &other) const;
  Bond const *operator*() const;
  // pre-increment
  ConstBondIterator_ &operator++();
  ConstBondIterator_ operator++(int);
  // pre-decrement
  ConstBondIterator_ &operator--();
  ConstBondIterator_ operator--(int);

 private:
  ROMol::EDGE_ITER _beg, _end, _pos;
  ROMol const *_mol{nullptr};
};
}  // namespace RDKit

#endif