/*
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * Copyright 2022, Danny Robson <danny@nerdcruft.net>
 */

#pragma once

#include <cruft/util/view.hpp>

#include <cstddef>


namespace cruft::serialise {
    template <typename ValueT>
    struct converter {
        static
        cruft::view<std::byte*>
        to_bytes [[nodiscard]] (
            cruft::view<std::byte*> dst,
            ValueT const &src
        );

        static
        ValueT
        from_bytes (cruft::view<std::byte*> &src);

        static std::size_t size (ValueT const&);
    };

    template <typename ValueT> struct converter<ValueT const> : public converter<ValueT> {};
    template <typename ValueT> struct converter<ValueT     &> : public converter<ValueT> {};

    template <typename ValueT>
    requires (std::is_trivial_v<ValueT>)
    struct converter<ValueT> {
        static
        cruft::view<std::byte*>
        to_bytes [[nodiscard]] (
            cruft::view<std::byte*> dst,
            ValueT const &src
        ) {
            if (dst.size () < sizeof (ValueT))
                throw std::bad_alloc ();

            return write (dst, src);
        }

        static
        ValueT
        from_bytes (cruft::view<std::byte*> &src)
        {
            return read<ValueT> (src);
        }


        static std::size_t size (ValueT const&) { return sizeof (ValueT); }
    };
}