// Copyright 2023 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#pragma once

#include <boost_wrapper/endian_conversion.h>

namespace DB
{
inline constexpr bool isLittleEndian()
{
    return (boost::endian::order::native == boost::endian::order::little);
}

/// Requires:
///   T is non-bool integral or scoped enumeration type
template <typename T>
inline T toLittleEndian(const T & x)
{
    if constexpr (boost::endian::order::native == boost::endian::order::little)
        return x;
    else
        return boost::endian::endian_reverse(x);
}

/// Requires:
///   T is integral, enumeration, float or double
template <typename T>
inline void toLittleEndianInPlace(T & x)
{
    if constexpr (boost::endian::order::native != boost::endian::order::little)
        boost::endian::endian_reverse_inplace(x);
}

template <typename T>
inline T toBigEndian(const T & x)
{
    if constexpr (boost::endian::order::native == boost::endian::order::little)
        return boost::endian::endian_reverse(x);
    else
        return x;
}

/// Requires:
///   T is integral, enumeration, float or double
template <typename T>
inline void toBigEndianInPlace(T & x)
{
    if constexpr (boost::endian::order::native == boost::endian::order::little)
        boost::endian::endian_reverse_inplace(x);
}

template <typename T>
inline T readLittleEndian(const char * addr)
{
    return toLittleEndian(*(reinterpret_cast<const T *>(addr)));
}

template <typename T>
inline T readBigEndian(const char * addr)
{
    return toBigEndian(*(reinterpret_cast<const T *>(addr)));
}

} // namespace DB