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/*! \internal \file
 *
 * \brief Handling of free energy parameters
 *
 * \author Christian Blau <blau@kth.se>
 * \ingroup module_mdlib
 */

#ifndef GMX_MDLIB_FREEENERGYPARAMETERS_H
#define GMX_MDLIB_FREEENERGYPARAMETERS_H

#include <array>

#include "gromacs/mdtypes/md_enums.h"
#include "gromacs/utility/enumerationhelpers.h"
#include "gromacs/utility/real.h"

struct t_lambda;

namespace gmx
{

/*! \brief Evaluate the current lambdas
 *
 * \param[in] step the current simulation step
 * \param[in] fepvals describing the lambda setup
 * \param[in] currentLambdaState the lambda state to use to set the lambdas, -1 if not set
 * \returns the current lambda-value array
 */
gmx::EnumerationArray<FreeEnergyPerturbationCouplingType, real> currentLambdas(int64_t         step,
                                                                               const t_lambda& fepvals,
                                                                               int currentLambdaState);

} // namespace gmx

#endif
