/*

 * International Chemical Identifier (InChI)

 * Version 1

 * Software version 1.06

 * December 15, 2020

 *

 * The InChI library and programs are free software developed under the

 * auspices of the International Union of Pure and Applied Chemistry (IUPAC).

 * Originally developed at NIST.

 * Modifications and additions by IUPAC and the InChI Trust.

 * Some portions of code were developed/changed by external contributors

 * (either contractor or volunteer) which are listed in the file

 * 'External-contributors' included in this distribution.

 *

 * IUPAC/InChI-Trust Licence No.1.0 for the

 * International Chemical Identifier (InChI)

 * Copyright (C) IUPAC and InChI Trust

 *

 * This library is free software; you can redistribute it and/or modify it

 * under the terms of the IUPAC/InChI Trust InChI Licence No.1.0,

 * or any later version.

 *

 * Please note that this library is distributed WITHOUT ANY WARRANTIES

 * whatsoever, whether expressed or implied.

 * See the IUPAC/InChI-Trust InChI Licence No.1.0 for more details.

 *

 * You should have received a copy of the IUPAC/InChI Trust InChI

 * Licence No. 1.0 with this library; if not, please e-mail:

 *

 * info@inchi-trust.org

 *

 */

#include "mode.h"

#include "ichicomn.h"

/**********************************************************************************/

AT_ISO_SORT_KEY make_iso_sort_key( int iso_atw_diff, int num_1H, int num_2H, int num_3H )

{

    AT_ISO_SORT_KEY iso_sort_key = 0, mult = 1;

    iso_sort_key += mult * num_1H;

    mult *= AT_ISO_SORT_KEY_MULT;

    iso_sort_key += mult * num_2H;

    mult *= AT_ISO_SORT_KEY_MULT;

    iso_sort_key += mult * num_3H;

    mult *= AT_ISO_SORT_KEY_MULT;

    iso_sort_key += mult * iso_atw_diff;

    return iso_sort_key;

}

/****************************************************************************

 Set sp_ATOM isotopic sort keys

****************************************************************************/

int set_atom_iso_sort_keys( int num_at,

                            sp_ATOM *at,

                            T_GROUP_INFO* t_group_info,

                            int *bHasIsotopicInTautomerGroups )

{

    int             i, num_isotopic = 0, bMergedTgroup;

    AT_ISO_SORT_KEY iso_sort_key;

    T_GROUP        *t_group =

        ( t_group_info &&

         t_group_info->t_group &&

         t_group_info->num_t_groups > 0 ) ? t_group_info->t_group : NULL;

    if (bHasIsotopicInTautomerGroups)

    {

        *bHasIsotopicInTautomerGroups = 0;

    }

    for (i = 0; i < num_at; i++)

    {

        bMergedTgroup = ( t_group_info && t_group_info->nIsotopicEndpointAtomNumber && ( at[i].cFlags & AT_FLAG_ISO_H_POINT ) );

        if (( !at[i].endpoint || !t_group ) && !bMergedTgroup)

        {

            iso_sort_key = make_iso_sort_key( at[i].iso_atw_diff, at[i].num_iso_H[0], at[i].num_iso_H[1], at[i].num_iso_H[2] );

        }

        else

        {

             /*  H isotopes go to the tautomer part of the CT (name) */

             /*  if (at[i].endpoint && t_group) ... */

            iso_sort_key = make_iso_sort_key( at[i].iso_atw_diff, 0, 0, 0 );

            if (bHasIsotopicInTautomerGroups)

            {

                *bHasIsotopicInTautomerGroups += ( at[i].num_iso_H[0] || at[i].num_iso_H[1] || at[i].num_iso_H[2] || bMergedTgroup );

            }

        }

        at[i].iso_sort_key = iso_sort_key;

        num_isotopic += ( iso_sort_key != 0 );

    }

    return num_isotopic;

}

#ifdef NEVER

/****************************************************************************/

int unpack_iso_sort_key( AT_ISO_SORT_KEY iso_sort_key,

                         S_CHAR *num_1H,

                         S_CHAR *num_2H,

                         S_CHAR *num_3H,

                         S_CHAR *iso_atw_diff )

{

    int is_negative;

    AT_ISO_SORT_KEY HOnlyAtwPart;

    static const AT_ISO_SORT_KEY MultAtwDiff = AT_ISO_SORT_KEY_MULT*AT_ISO_SORT_KEY_MULT*AT_ISO_SORT_KEY_MULT;

    if (!iso_sort_key)

    {

        *num_1H = *num_2H = *num_3H = *iso_atw_diff = 0;

        return 0;

    }

    else

    {

        if (iso_sort_key < 0)

        {

            is_negative = 1;

            iso_sort_key = -iso_sort_key;

            HOnlyAtwPart = MultAtwDiff - iso_sort_key % MultAtwDiff;

            iso_sort_key += HOnlyAtwPart;

        }

        else

        {

            is_negative = 0;

            HOnlyAtwPart = iso_sort_key % MultAtwDiff;

            iso_sort_key -= HOnlyAtwPart;

        }

    }

    iso_sort_key /= MultAtwDiff;

    *num_1H = (S_CHAR) ( HOnlyAtwPart % AT_ISO_SORT_KEY_MULT );

    HOnlyAtwPart /= AT_ISO_SORT_KEY_MULT;

    *num_2H = (S_CHAR) ( HOnlyAtwPart % AT_ISO_SORT_KEY_MULT );

    HOnlyAtwPart /= AT_ISO_SORT_KEY_MULT;

    *num_3H = (S_CHAR) ( HOnlyAtwPart % AT_ISO_SORT_KEY_MULT );

    *iso_atw_diff = (S_CHAR) ( is_negative ? -iso_sort_key : iso_sort_key );

    return 1;

}

#endif