// ************************************************************************** //
//
//  BornAgain: simulate and fit scattering at grazing incidence
//
//! @file      Core/Material/MaterialUtils.h
//! @brief     Declares functions in namespace MaterialUtils
//!
//! @homepage  http://www.bornagainproject.org
//! @license   GNU General Public License v3 or higher (see COPYING)
//! @copyright Forschungszentrum Jülich GmbH 2018
//! @authors   Scientific Computing Group at MLZ (see CITATION, AUTHORS)
//
// ************************************************************************** //

#ifndef BORNAGAIN_CORE_MATERIAL_MATERIALUTILS_H
#define BORNAGAIN_CORE_MATERIAL_MATERIALUTILS_H

#include "Core/Basics/Complex.h"
#include "Core/Material/Material.h"
#include "Core/Vector/EigenCore.h"
#include "Core/Vector/Vectors3D.h"

//! A number of materials-related helper functions for internal use
//! @ingroup materials

namespace MaterialUtils
{

//! Function for calculating the reduced potential, used for obtaining the Fresnel coefficients
//! (non-polarized material case)

BA_CORE_API_ complex_t ScalarReducedPotential(complex_t n, kvector_t k, double n_ref);

//! Function for calculating the reduced potential, used for obtaining the Fresnel coefficients
//! (polarized material case)

BA_CORE_API_ Eigen::Matrix2cd PolarizedReducedPotential(complex_t n, kvector_t b_field, kvector_t k,
                                                        double n_ref);

//! Utility to compute magnetization correction for reduced potential and scattering length density

template <typename T>
BA_CORE_API_ Eigen::Matrix2cd MagnetizationCorrection(complex_t unit_factor, double magnetic_factor,
                                                      BasicVector3D<T> polarization);

//! Checks if all non-default materials in _materials_ are of the same type and returns this type.
//! If several types of materials are involved, InvalidMaterialType identifier is returned.

BA_CORE_API_ MATERIAL_TYPES checkMaterialTypes(const std::vector<const Material*>& materials);

} // namespace MaterialUtils

#endif // BORNAGAIN_CORE_MATERIAL_MATERIALUTILS_H