/****************************************************************************
** Copyright (c) 2021, Fougue Ltd. <http://www.fougue.pro>
** All rights reserved.
** See license at https://github.com/fougue/mayo/blob/master/LICENSE.txt
****************************************************************************/

#pragma once

namespace Mayo {

enum class Unit {
    None,

    // Base
    Length, // Meter(m)
    Mass,   // Kilogram(kg)
    Time,   // Second(s)
    ElectricCurrent,   // Ampere(A)
    ThermodynamicTemperature, // Kelvin(K)
    AmountOfSubstance, // Mole(mol)
    LuminousIntensity, // Candela(cd)
    Angle,  // Radian(rad)

    // Derived
    Area,     // m²
    Volume,   // m^3
    Velocity, // m/s
    Acceleration, // m/s²
    Density,  // kg/m^3
    Pressure  // kg/m.s² (or N/m²)
};

enum LengthUnit {
    // SI
    Nanometer, Micrometer, Millimeter, Centimeter, Decimeter, Meter, Kilometer,
    NauticalMile,
    // Imperial UK
    Thou, Inch, Link, Foot, Yard, Rod, Chain, Furlong, Mile, League
};

enum AngleUnit {
    Radian, Degree
};

enum AreaUnit {
    // SI
    SquareMillimeter, SquareCentimeter, SquareMeter, SquareKilometer,
    // Imperial UK
    SquareInch, SquareFoot, SquareYard, SquareMile
};

enum VolumeUnit {
    // SI
    CubicMillimeter, CubicCentimeter, CubicMeter,
    // Imperial UK
    CubicInch, CubicFoot,
    // Others
    Liter, ImperialGallon, USGallon
};

#if 0
enum class BaseUnit {
    Length = 0, // Meter(m)
    Mass,       // Kilogram(kg)
    Time,       // Second(s)
    ElectricCurrent,   // Ampere(A)
    ThermodynamicTemperature, // Kelvin(K)
    AmountOfSubstance, // Mole(mol)
    LuminousIntensity, // Candela(cd)
    Angle       // Degree(°)
};

class Unit {
public:
    static const Unit None;

    static const Unit Length;
    static const Unit Mass;
    static const Unit Time;
    static const Unit Angle;

    static const Unit Area;
    static const Unit Volume;

    static const Unit Velocity;
    static const Unit Acceleration;

    static const Unit Density;
    static const Unit Pressure;

    const std::string& symbol() const;

private:
    using ArrayPowBaseUnit = std::array<int8_t, 8>;

    Unit() = default;
    Unit(BaseUnit base);
    Unit(const ArrayPowBaseUnit& arrayPow);
    Unit& operator=(BaseUnit base);
    Unit& operator=(const Unit& unit) = delete;

    void buildSymbol();

    friend Unit operator*(const Unit& unit, BaseUnit baseUnit);
    friend Unit operator*(const Unit& lhs, const Unit& rhs);
    friend Unit operator/(const Unit& unit, BaseUnit baseUnit);
    friend Unit operator/(const Unit& lhs, const Unit& rhs);

    ArrayPowBaseUnit m_powBaseUnit = {};
    std::string m_symbol;
};
#endif

} // namespace Mayo