#pragma once

#ifdef _MSC_VER
#include <stdlib.h>
#endif

enum class Endian
{
    Little,
    Big
};

// Reverses the byte order of a primitive value of any typical size
template <typename T>
inline constexpr T ReverseBytes(T n)
{
    // 1 byte, cannot reverse
    if constexpr (sizeof(T) == 1) return n;

#ifdef __GNUC__
    // GCC intrinsic byte swaps
    // https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#index-_005f_005fbuiltin_005fbswap16
    
    if constexpr (sizeof(T) == 2)      return __builtin_bswap16(n); // 2 bytes
    else if constexpr (sizeof(T) == 4) return __builtin_bswap32(n); // 4 bytes
    else if constexpr (sizeof(T) == 8) return __builtin_bswap64(n); // 8 bytes

#elif defined(_MSC_VER)
    // MSVC intrinsic byteswaps
    // https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/byteswap-uint64-byteswap-ulong-byteswap-ushort

    if constexpr (sizeof(T) == 2)      return _byteswap_ushort(n); // 2 bytes
    else if constexpr (sizeof(T) == 4) return _byteswap_ulong(n);  // 4 bytes
    else if constexpr (sizeof(T) == 8) return _byteswap_uint64(n); // 8 bytes
#endif
    //else static_assert(false, "Attempted to call ReverseBytes() on type with unusual size.");
}