/***
    Copyright (C) 2022 J Reece Wilson (a/k/a "Reece"). All rights reserved.

    File: auEndianness.hpp
    Date: 2022-2-6
    Author: Reece
***/
#pragma once

template <class T>
struct AuEndianUtils
{
    static T Swap(T in);
};

template <class T>
inline T AuEndianUtils<T>::Swap(T in)
{
    if constexpr (sizeof(T) == 8) 
        return   (T(in) & 0xFF) << T(56) |
                (T(in >> T(8)) & T(0xFF)) <<  T(48) |
                (T(in >> T(16)) & T(0xFF)) << T(40) |
                (T(in >> T(24)) & T(0xFF)) << T(32) |
                (T(in >> T(32)) & T(0xFF)) << T(24) |
                (T(in >> T(40)) & T(0xFF)) << T(16) |
                (T(in >> T(48)) & T(0xFF)) << T(8) |
                (T(in >> T(56)) & T(0xFF));

    if constexpr (sizeof(T) == 4) 
        return   T(in & 0xFF) << 24 |
                (T(in >> 8) & 0xFF) << 16 |
                (T(in >> 16) & 0xFF) << 8 |
                (T(in >> 24) & 0xFF);

    if constexpr (sizeof(T) == 2) 
        return   (in & 0xFF) << 8 |
                ((in >> 8) & 0xFF);
   
    return in;
}

#if defined(AURORA_COMPILER_MSVC)

template <>
inline AuUInt64 AuEndianUtils<AuUInt64>::Swap(AuUInt64 in)
{
    return _byteswap_uint64(in);
}

template <>
inline AuUInt32 AuEndianUtils<AuUInt32>::Swap(AuUInt32 in)
{
    return _byteswap_ulong(in);
}

template <>
inline unsigned long AuEndianUtils<unsigned long>::Swap(unsigned long in)
{
    return _byteswap_ulong(in);
}

template <>
inline AuUInt16 AuEndianUtils<AuUInt16>::Swap(AuUInt16 in)
{
    return _byteswap_ushort(in);
}

#elif defined(AURORA_COMPILER_CLANG)

template <>
inline AuUInt64 AuEndianUtils<AuUInt64>::Swap(AuUInt64 in)
{
    return __builtin_bswap64(in);
}

template <>
inline AuUInt32 AuEndianUtils<AuUInt32>::Swap(AuUInt32 in)
{
    return __builtin_bswap32(in);
}

template <>
inline AuUInt16 AuEndianUtils<AuUInt16>::Swap(AuUInt16 in)
{
    return __builtin_bswap16(in);
}

#endif

template <class Type_t>
inline auline Type_t AuFlipEndian(Type_t in)
{
    return AuEndianUtils<Type_t>::Swap(in);
}

template <class Type_t>
inline auline Type_t AuEndianFlip(Type_t in)
{
    return AuEndianUtils<Type_t>::Swap(in);
}

template <class Type_t>
inline auline Type_t AuEndianNormalizeLittle(Type_t in)
{
#if defined(AU_CPU_ENDIAN_LITTLE)
    return (in);
#else
    return AuFlipEndian(in);
#endif
}

template <class Type_t>
inline auline Type_t AuEndianNormalizeBig(Type_t in)
{
#if defined(AU_CPU_ENDIAN_LITTLE)
    return AuFlipEndian(in);
#else
    return (in);
#endif
}