//-----------------------------------------------------------------------------
/** @file libpentobi_base/Color.h
    @author Markus Enzenberger
    @copyright GNU General Public License version 3 or later */
//-----------------------------------------------------------------------------

#ifndef LIBPENTOBI_BASE_COLOR_H
#define LIBPENTOBI_BASE_COLOR_H

#include <cstdint>
#include "libboardgame_base/Assert.h"

namespace libpentobi_base {

using namespace std;

//-----------------------------------------------------------------------------

class Color
{
public:
    using IntType = uint_fast8_t;

    class Iterator
    {
    public:
        explicit Iterator(IntType i) { m_i = i; }

        bool operator==(Iterator it) const { return m_i == it.m_i; }

        bool operator!=(Iterator it) const { return m_i != it.m_i; }

        void operator++() { ++m_i; }

        Color operator*() const { return Color(m_i); }

    private:
        IntType m_i;
    };

    class Range
    {
    public:
        explicit Range(IntType nu_colors)
            : m_nu_colors(nu_colors)
        { }

        Iterator begin() const { return Iterator(0); }

        Iterator end() const { return Iterator(m_nu_colors); }

    private:
        IntType m_nu_colors;
    };

    static constexpr IntType range = 4;

    Color();

    explicit Color(IntType i);

    bool operator==(Color c) const;

    bool operator!=(Color c) const { return ! operator==(c); }

    bool operator<(Color c) const;

    IntType to_int() const;

    Color get_next(IntType nu_colors) const;

    Color get_previous(IntType nu_colors) const;

private:
    static constexpr IntType value_uninitialized = range;

    IntType m_i;

#ifdef LIBBOARDGAME_DEBUG
    bool is_initialized() const { return m_i < value_uninitialized; }
#endif
};


inline Color::Color()
{
#ifdef LIBBOARDGAME_DEBUG
    m_i = value_uninitialized;
#endif
}

inline Color::Color(IntType i)
{
    LIBBOARDGAME_ASSERT(i < range);
    m_i = i;
}

inline bool Color::operator==(Color c) const
{
    LIBBOARDGAME_ASSERT(is_initialized());
    LIBBOARDGAME_ASSERT(c.is_initialized());
    return m_i == c.m_i;
}

inline bool Color::operator<(Color c) const
{
    LIBBOARDGAME_ASSERT(is_initialized());
    LIBBOARDGAME_ASSERT(c.is_initialized());
    return m_i < c.m_i;
}

inline Color Color::get_next(IntType nu_colors) const
{
    return Color(static_cast<IntType>(m_i + 1) % nu_colors);
}

inline Color Color::get_previous(IntType nu_colors) const
{
    return Color(static_cast<IntType>(m_i + nu_colors - 1) % nu_colors);
}

inline Color::IntType Color::to_int() const
{
    LIBBOARDGAME_ASSERT(is_initialized());
    return m_i;
}

//-----------------------------------------------------------------------------

/** Unrolled loop over all colors. */
template<class FUNCTION>
inline void for_each_color(FUNCTION f)
{
    static_assert(Color::range == 4);
    f(Color(0));
    f(Color(1));
    f(Color(2));
    f(Color(3));
}

//-----------------------------------------------------------------------------

} // namespace libpentobi_base

#endif // LIBPENTOBI_BASE_COLOR_H
