#ifndef BOOST_QVM_QUAT_HPP_INCLUDED
#define BOOST_QVM_QUAT_HPP_INCLUDED

// Copyright 2008-2022 Emil Dotchevski and Reverge Studios, Inc.

// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

#include <boost/qvm/detail/quat_assign.hpp>
#include <boost/qvm/assert.hpp>
#include <boost/qvm/static_assert.hpp>

namespace boost { namespace qvm {

template <class T>
struct
quat
    {
    T a[4];
    template <class R
#if __cplusplus >= 201103L
        , class = typename enable_if<is_quat<R> >::type
#endif
    >
    operator R() const
        {
        R r;
        assign(r,*this);
        return r;
        }
    };

template <class Q>
struct quat_traits;

template <class T>
struct
quat_traits< quat<T> >
    {
    typedef quat<T> this_quaternion;
    typedef T scalar_type;

    template <int I>
    static
    BOOST_QVM_CONSTEXPR BOOST_QVM_INLINE_CRITICAL
    scalar_type
    read_element( this_quaternion const & x )
        {
        BOOST_QVM_STATIC_ASSERT(I>=0);
        BOOST_QVM_STATIC_ASSERT(I<4);
        return x.a[I];
        }

    template <int I>
    static
    BOOST_QVM_CONSTEXPR BOOST_QVM_INLINE_CRITICAL
    scalar_type &
    write_element( this_quaternion & x )
        {
        BOOST_QVM_STATIC_ASSERT(I>=0);
        BOOST_QVM_STATIC_ASSERT(I<4);
        return x.a[I];
        }
    };

} }

#endif
