/**
 * \file
 * \copyright
 * Copyright (c) 2012-2021, OpenGeoSys Community (http://www.opengeosys.org)
 *            Distributed under a Modified BSD License.
 *              See accompanying file LICENSE.txt or
 *              http://www.opengeosys.org/project/license
 */

#include "DensityLegacy.h"

namespace
{
// parameters from least squares fit (experimental data)
const double DensityLegacy_c[] = {
    0.34102920966608297,    -0.0013106032830951296, -0.00060754147575378876,
    3.7843404172683339e-07, 4.0107503869519016e-07, 3.1274595098338057e-10,
    -7.610441241719489e-11};

}  // namespace

namespace Adsorption
{
double DensityLegacy::getAdsorbateDensity(const double T_Ads) const
{
    // set reference state for adsorbate EOS in Hauer
    const double T0 = 293.15;
    const double rho0 = 998.084;
    const double alpha0 = 2.06508e-4;  // K; kg/m^3; 1/K

    return (rho0 * (1. - alpha0 * (T_Ads - T0)));  // in kg/m^3
}

// Thermal expansivity model for water found in the works of Hauer
double DensityLegacy::getAlphaT(const double T_Ads) const
{
    // set reference state for adsorbate EOS in Hauer
    const double T0 = 293.15;
    const double alpha0 = 2.06508e-4;  // K; 1/K

    return (alpha0 / (1. - alpha0 * (T_Ads - T0)));  // in 1/K
}

// Characteristic curve. Return W (A)
double DensityLegacy::characteristicCurve(const double A) const
{
    double W = curvePolyfrac(DensityLegacy_c, A);  // cm^3/g

    if (W < 0.0)
    {
        W = 0.0;  // TODO [CL] debug output
    }

    return W / 1.e3;  // m^3/kg
}

double DensityLegacy::dCharacteristicCurve(const double A) const
{
    return dCurvePolyfrac(DensityLegacy_c, A);
}

}  // namespace Adsorption