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 */
#include "gmxpre.h"

#include "units.h"

#include <cstdio>

#include "gromacs/utility/cstringutil.h"

double convert2gmx(double x, int unit)
{
    switch (unit)
    {
        case eg2cAngstrom: return x * A2NM;
        case eg2cNm: return x;
        case eg2cBohr: return x * BOHR2NM;
        case eg2cKcal_Mole: return x / CAL2JOULE;
        case eg2cHartree: return x * ONE_4PI_EPS0 / BOHR2NM; // NOLINT bugprone-branch-clone
        case eg2cHartree_e: return x * ONE_4PI_EPS0 / BOHR2NM;
        case eg2cAngstrom3: return x * A2NM * A2NM * A2NM;
        case eg2cCoulomb: return x / E_CHARGE;
        case eg2cDebye: return x * DEBYE2ENM;
        case eg2cElectron: return x;
        case eg2cBuckingham: return x * A2NM * DEBYE2ENM;
        default: fprintf(stderr, "Unknown unit %d, not converting.\n", unit);
    }
    return x;
}

double gmx2convert(double x, int unit)
{
    switch (unit)
    {
        case eg2cAngstrom: return x / A2NM;
        case eg2cNm: return x;
        case eg2cBohr: return x / BOHR2NM;
        case eg2cKcal_Mole: return x * CAL2JOULE;
        case eg2cHartree: return x / (ONE_4PI_EPS0 / BOHR2NM); // NOLINT bugprone-branch-clone
        case eg2cHartree_e: return x / (ONE_4PI_EPS0 / BOHR2NM);
        case eg2cAngstrom3: return x / (A2NM * A2NM * A2NM);
        case eg2cCoulomb: return x * E_CHARGE;
        case eg2cDebye: return x / DEBYE2ENM;
        case eg2cElectron: return x;
        case eg2cBuckingham: return x / (A2NM * DEBYE2ENM);
        default: fprintf(stderr, "Unknown unit %d, not converting.\n", unit);
    }
    return x;
}

/* This has to have the same order as the enums. */
static const char* eg2c_names[eg2cNR] = { "Angstrom", "Nm",        "Bohr",      "Kcal_Mole",
                                          "Hartree",  "Hartree_e", "Angstrom3", "Coulomb",
                                          "Debye",    "Electron",  "Buckingham" };

int string2unit(char* string)
{
    int i;

    for (i = 0; (i < eg2cNR); i++)
    {
        if (gmx_strcasecmp(string, eg2c_names[i]) == 0)
        {
            return i;
        }
    }
    return -1;
}

const char* unit2string(int unit)
{
    if ((unit >= 0) && (unit < eg2cNR))
    {
        return eg2c_names[unit];
    }

    return nullptr;
}
