Density.h

/***************************************************************************
 *   Copyright (C) 2023 by Stefan Kebekus                                  *
 *   stefan.kebekus@gmail.com                                              *
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 *   it under the terms of the GNU General Public License as published by  *
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 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
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 *   GNU General Public License for more details.                          *
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 ***************************************************************************/
 
#pragma once
 
#include <QObject>
#include <QQmlEngine>
#include <QtMath>
 
 
namespace Units {

class Density {
    Q_GADGET
    QML_VALUE_TYPE(density)
 
public:
    static constexpr auto fromKgPerCubeMeter(double densityInKgPerCubeMeter) -> Density
    {
        Density result;
        result.m_densityInKgPerCubeMeter = densityInKgPerCubeMeter;
        return result;
    }
 

    [[nodiscard]] Q_INVOKABLE bool isFinite() const
    {
        return std::isfinite(m_densityInKgPerCubeMeter);
    }

    [[nodiscard]] Q_INVOKABLE std::partial_ordering operator<=>(const Units::Density& rhs) const = default;

    [[nodiscard]] Q_INVOKABLE double toKgPerCubeMeter() const
    {
        return m_densityInKgPerCubeMeter;
    }
 
 
private:
    // Density in kg per m³
    double m_densityInKgPerCubeMeter{ NAN };
};
} // namespace Units
 
 
// Declare meta types
Q_DECLARE_METATYPE(Units::Density)