// This file is originally from Trantor - Socket.cc

// Copyright (c) 2016-2021, Tao An.  All rights reserved.

// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
//   * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//   * Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//   * Neither the name of Tao An nor the names of other contributors
// may be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "socket.h"
#include <assert.h>
#include <sys/types.h>
#include "core/log/logger.h"
#ifdef _WIN32
#include <ws2tcpip.h>
#else
#include <netinet/tcp.h>
#include <sys/socket.h>
#endif

using namespace trantor;

bool Socket::isSelfConnect(int sockfd) {
	struct sockaddr_in6 localaddr = getLocalAddr(sockfd);
	struct sockaddr_in6 peeraddr = getPeerAddr(sockfd);
	if (localaddr.sin6_family == AF_INET) {
		const struct sockaddr_in *laddr4 =
				reinterpret_cast<struct sockaddr_in *>(&localaddr);
		const struct sockaddr_in *raddr4 =
				reinterpret_cast<struct sockaddr_in *>(&peeraddr);
		return laddr4->sin_port == raddr4->sin_port &&
			   laddr4->sin_addr.s_addr == raddr4->sin_addr.s_addr;
	} else if (localaddr.sin6_family == AF_INET6) {
		return localaddr.sin6_port == peeraddr.sin6_port &&
			   memcmp(&localaddr.sin6_addr,
					   &peeraddr.sin6_addr,
					   sizeof localaddr.sin6_addr) == 0;
	} else {
		return false;
	}
}

void Socket::bindAddress(const InetAddress &localaddr) {
	assert(sockFd_ > 0);
	int ret;
	if (localaddr.isIpV6())
		ret = ::bind(sockFd_, localaddr.getSockAddr(), sizeof(sockaddr_in6));
	else
		ret = ::bind(sockFd_, localaddr.getSockAddr(), sizeof(sockaddr_in));

	if (ret == 0)
		return;
	else {
		LOG_SYSERR << ", Bind address failed at " << localaddr.toIpPort();
		exit(1);
	}
}
void Socket::listen() {
	assert(sockFd_ > 0);
	int ret = ::listen(sockFd_, SOMAXCONN);
	if (ret < 0) {
		LOG_SYSERR << "listen failed";
		exit(1);
	}
}
int Socket::accept(InetAddress *peeraddr) {
	struct sockaddr_in6 addr6;
	memset(&addr6, 0, sizeof(addr6));
	socklen_t size = sizeof(addr6);
#ifdef __linux__
	int connfd = ::accept4(sockFd_,
			(struct sockaddr *)&addr6,
			&size,
			SOCK_NONBLOCK | SOCK_CLOEXEC);
#else
	int connfd =
			static_cast<int>(::accept(sockFd_, (struct sockaddr *)&addr6, &size));
	setNonBlockAndCloseOnExec(connfd);
#endif
	if (connfd >= 0) {
		peeraddr->setSockAddrInet6(addr6);
	}
	return connfd;
}
void Socket::closeWrite() {
#ifndef _WIN32
	if (::shutdown(sockFd_, SHUT_WR) < 0)
#else
	if (::shutdown(sockFd_, SD_SEND) < 0)
#endif
	{
		LOG_SYSERR << "sockets::shutdownWrite";
	}
}
int Socket::read(char *buffer, uint64_t len) {
#ifndef _WIN32
	return ::read(sockFd_, buffer, len);
#else
	return recv(sockFd_, buffer, static_cast<int>(len), 0);
#endif
}

struct sockaddr_in6 Socket::getLocalAddr(int sockfd) {
	struct sockaddr_in6 localaddr;
	memset(&localaddr, 0, sizeof(localaddr));
	socklen_t addrlen = static_cast<socklen_t>(sizeof localaddr);
	if (::getsockname(sockfd,
				static_cast<struct sockaddr *>((void *)(&localaddr)),
				&addrlen) < 0) {
		LOG_SYSERR << "sockets::getLocalAddr";
	}
	return localaddr;
}

struct sockaddr_in6 Socket::getPeerAddr(int sockfd) {
	struct sockaddr_in6 peeraddr;
	memset(&peeraddr, 0, sizeof(peeraddr));
	socklen_t addrlen = static_cast<socklen_t>(sizeof peeraddr);
	if (::getpeername(sockfd,
				static_cast<struct sockaddr *>((void *)(&peeraddr)),
				&addrlen) < 0) {
		LOG_SYSERR << "sockets::getPeerAddr";
	}
	return peeraddr;
}

void Socket::setTcpNoDelay(bool on) {
#ifdef _WIN32
	char optval = on ? 1 : 0;
#else
	int optval = on ? 1 : 0;
#endif
	::setsockopt(sockFd_,
			IPPROTO_TCP,
			TCP_NODELAY,
			&optval,
			static_cast<socklen_t>(sizeof optval));
	// TODO CHECK
}

void Socket::setReuseAddr(bool on) {
#ifdef _WIN32
	char optval = on ? 1 : 0;
#else
	int optval = on ? 1 : 0;
#endif
	::setsockopt(sockFd_,
			SOL_SOCKET,
			SO_REUSEADDR,
			&optval,
			static_cast<socklen_t>(sizeof optval));
	// TODO CHECK
}

void Socket::setReusePort(bool on) {
#ifdef SO_REUSEPORT
#ifdef _WIN32
	char optval = on ? 1 : 0;
#else
	int optval = on ? 1 : 0;
#endif
	int ret = ::setsockopt(sockFd_,
			SOL_SOCKET,
			SO_REUSEPORT,
			&optval,
			static_cast<socklen_t>(sizeof optval));
	if (ret < 0 && on) {
		LOG_SYSERR << "SO_REUSEPORT failed.";
	}
#else
	if (on) {
		LOG_ERROR << "SO_REUSEPORT is not supported.";
	}
#endif
}

void Socket::setKeepAlive(bool on) {
#ifdef _WIN32
	char optval = on ? 1 : 0;
#else
	int optval = on ? 1 : 0;
#endif
	::setsockopt(sockFd_,
			SOL_SOCKET,
			SO_KEEPALIVE,
			&optval,
			static_cast<socklen_t>(sizeof optval));
	// TODO CHECK
}

int Socket::getSocketError() {
#ifdef _WIN32
	char optval;
#else
	int optval;
#endif
	socklen_t optlen = static_cast<socklen_t>(sizeof optval);

	if (::getsockopt(sockFd_, SOL_SOCKET, SO_ERROR, &optval, &optlen) < 0) {
		return errno;
	} else {
		return optval;
	}
}

Socket::~Socket() {
	LOG_TRACE << "Socket deconstructed:" << sockFd_;
	if (sockFd_ >= 0)
#ifndef _WIN32
		close(sockFd_);
#else
		closesocket(sockFd_);
#endif
}