// SPDX-License-Identifier: BSD-2-Clause
// author: Max Kellermann <max.kellermann@gmail.com>

#include "IPv6Address.hxx"
#include "IPv4Address.hxx"

#include <cassert>

#include <string.h>

IPv6Address::IPv6Address(SocketAddress src) noexcept
	:address(src.CastTo<struct sockaddr_in6>())
{
	assert(!src.IsNull());
	assert(src.GetFamily() == AF_INET6);
}

bool
IPv6Address::IsAny() const noexcept
{
	assert(IsValid());

	return memcmp(&address.sin6_addr,
		      &in6addr_any, sizeof(in6addr_any)) == 0;
}

IPv4Address
IPv6Address::UnmapV4() const noexcept
{
	assert(IsV4Mapped());

	struct sockaddr_in buffer{};
	buffer.sin_family = AF_INET;
	memcpy(&buffer.sin_addr, ((const char *)&address.sin6_addr) + 12,
	       sizeof(buffer.sin_addr));
	buffer.sin_port = address.sin6_port;

	return buffer;
}

template<typename T>
static void
BitwiseAndT(T *dest, const T *a, const T *b, size_t n)
{
	while (n-- > 0)
		*dest++ = *a++ & *b++;
}

static void
BitwiseAnd32(void *dest, const void *a, const void *b, size_t n)
{
	using value_type = uint32_t;
	using pointer = value_type *;
	using const_pointer = const value_type *;

	BitwiseAndT(pointer(dest), const_pointer(a), const_pointer(b),
		    n / sizeof(value_type));
}

IPv6Address
IPv6Address::operator&(const IPv6Address &other) const
{
	IPv6Address result;
	BitwiseAnd32(&result, this, &other,
		     sizeof(result));
	return result;
}