/*************************************************************************
*    UrBackup - Client/Server backup system
*    Copyright (C) 2011-2016 Martin Raiber
*
*    This program is free software: you can redistribute it and/or modify
*    it under the terms of the GNU Affero General Public License as published by
*    the Free Software Foundation, either version 3 of the License, or
*    (at your option) any later version.
*
*    This program is distributed in the hope that it will be useful,
*    but WITHOUT ANY WARRANTY; without even the implied warranty of
*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
*    GNU Affero General Public License for more details.
*
*    You should have received a copy of the GNU Affero General Public License
*    along with this program.  If not, see <http://www.gnu.org/licenses/>.
**************************************************************************/

#include "vld.h"

#include "AcceptThread.h"
#include "Server.h"
#include "stringtools.h"
#include "SelectThread.h"
#include "Client.h"
#include <memory.h>
#ifndef _WIN32
#include <errno.h>
#endif

extern bool run;

namespace
{
	bool prepareSocket(SOCKET s)
	{
#if !defined(_WIN32) && !defined(SOCK_CLOEXEC)
		fcntl(s, F_SETFD, fcntl(s, F_GETFD, 0) | FD_CLOEXEC);
#endif

		int optval = 1;
		int rc = setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char*)&optval, sizeof(int));
		if (rc == SOCKET_ERROR)
		{
			Server->Log("Failed setting SO_REUSEADDR", LL_ERROR);
			return false;
		}
#ifdef __APPLE__
		optval = 1;
		setsockopt(s, SOL_SOCKET, SO_NOSIGPIPE, (void*)&optval, sizeof(optval));
#endif
		return true;
	}
}

OutputCallback::OutputCallback(SOCKET fd_)
{
	  fd=fd_;
}

OutputCallback::~OutputCallback()
{
    closesocket(fd);
}

void OutputCallback::operator() (const void* buf, size_t count)
{
	size_t sent=0;
	do
	{
		int rc = send(fd, (const char*)buf+sent, static_cast<int>(count-sent), MSG_NOSIGNAL);
		if (rc < 0)
		{
			int ec;
	#ifdef _WIN32
			ec=GetLastError();
	#else
			ec=errno;
	#endif
			Server->Log("Send failed in OutputCallback ec="+convert(ec), LL_INFO);
			throw std::runtime_error("Send failed in OutputCallback");
		}
		else
		{
			sent+=rc;
		}
	}
	while(sent<count);
}

CAcceptThread::CAcceptThread( unsigned int nWorkerThreadsPerMaster, unsigned short int uPort ) 
	: error(false), s_v6(SOCKET_ERROR), s(SOCKET_ERROR)
{
	WorkerThreadsPerMaster=nWorkerThreadsPerMaster;

	bool has_ipv4 = Server->getServerParameter("disable_ipv4").empty();
	bool has_ipv6 = Server->getServerParameter("disable_ipv6").empty();

	if (!has_ipv4 && !has_ipv6)
	{
		Server->Log("CAcceptThread: IPv4 and IPv6 disabled", LL_ERROR);
		error = true;
		return;
	}

	if (has_ipv4)
	{
		if (!init_socket_v4(uPort))
		{
			if (Server->getServerParameter("ipv4_optional").empty()
				|| !has_ipv6)
			{
				error = true;
				return;
			}
		}
	}

	if (has_ipv6)
	{
		if (!init_socket_v6(uPort))
		{
			if (!Server->getServerParameter("ipv6_required").empty()
				|| !has_ipv4)
			{
				error = true;
				return;
			}
		}
	}

	Server->Log("Server started up successfully!",LL_INFO);
}

CAcceptThread::~CAcceptThread()
{
	closesocket(s);
	if (s_v6 != SOCKET_ERROR)
		closesocket(s_v6);
	Server->Log("Deleting SelectThreads..");
	for(size_t i=0;i<SelectThreads.size();++i)
	{
		delete SelectThreads[i];
	}
}

#ifndef _WIN32
void printLinError(void)
{
	switch(errno)
	{
		case EWOULDBLOCK: Server->Log("Reason: EWOULDBLOCK", LL_ERROR); break;
		case EBADF: Server->Log("Reason: EBADF", LL_ERROR); break;
		case ECONNABORTED: Server->Log("Reason: ECONNABORTED", LL_ERROR); break;
		case EINTR: Server->Log("Reason: EINTR", LL_ERROR); break;
		case EINVAL: Server->Log("Reason: EINVAL", LL_ERROR); break;
		case EMFILE: Server->Log("Reason: EMFILE", LL_ERROR); break;
		case ENFILE: Server->Log("Reason: ENFILE", LL_ERROR); break;
		case ENOTSOCK: Server->Log("Reason: ENOTSOCK", LL_ERROR); break;
		case EFAULT: Server->Log("Reason: EFAULT", LL_ERROR); break;
		case ENOBUFS: Server->Log("Reason: ENOBUFS", LL_ERROR); break;
		case ENOMEM: Server->Log("Reason: ENOMEM", LL_ERROR); break;
		case EPROTO: Server->Log("Reason: EPROTO", LL_ERROR); break;
		case EPERM: Server->Log("Reason: EPERM", LL_ERROR); break;
	}
}
#endif

void CAcceptThread::operator()(bool single)
{
	do
	{
		socklen_t addrsize=sizeof(sockaddr_in);

#ifdef _WIN32
		fd_set fdset;
		FD_ZERO(&fdset);
		if(s!=SOCKET_ERROR)
			FD_SET(s, &fdset);
		if(s_v6!=SOCKET_ERROR)
			FD_SET(s_v6, &fdset);

		timeval lon;	
		lon.tv_sec=1;
		lon.tv_usec=0;

		_i32 rc=select((int)s+1, &fdset, 0, 0, &lon);
#else
		pollfd conn[2];
		conn[0].fd = s;
		conn[0].events = POLLIN;
		conn[0].revents = 0;
		conn[1].revents = 0;
		nfds_t num_fds = 1;

		if (s_v6 != SOCKET_ERROR)
		{
			conn[1].fd = s_v6;
			conn[1].events = POLLIN;
			num_fds = 2;
		}

		int rc = poll(conn, num_fds, 1000);
#endif
		if (rc<0)
			return;

		if (rc > 0)
		{
			for (size_t n = 0; n < 2; ++n)
			{
#ifdef _WIN32
				SOCKET accept_socket = n == 0 ? s : s_v6;
				if (accept_socket == SOCKET_ERROR)
					continue;
				if (!FD_ISSET(accept_socket, &fdset))
					continue;
#else
				if (conn[n].revents == 0)
					continue;
				SOCKET accept_socket = conn[n].fd;
#endif

				sockaddr_in naddr;
				SOCKET ns = ACCEPT_CLOEXEC(accept_socket, (sockaddr*)&naddr, &addrsize);
				if (ns != SOCKET_ERROR)
				{

#ifdef __APPLE__
					int optval = 1;
					setsockopt(ns, SOL_SOCKET, SO_NOSIGPIPE, (void*)&optval, sizeof(optval));
#endif
					//Server->Log("New Connection incomming", LL_INFO);

					OutputCallback *output = new OutputCallback(ns);
					FCGIProtocolDriver *driver = new FCGIProtocolDriver(*output);

					CClient *client = new CClient();
					client->set(ns, output, driver);

					AddToSelectThread(client);
				}
				else
				{
					Server->Log("Accepting client failed", LL_ERROR);
#ifndef _WIN32
					printLinError();
#endif
					Server->wait(1000);
				}
			}
		}
	}while(!single);
}

void CAcceptThread::AddToSelectThread(CClient *client)
{
	for(size_t i=0;i<SelectThreads.size();++i)
	{
		if( SelectThreads[i]->FreeClients()>0 )
		{
			SelectThreads[i]->AddClient( client );
			return;
		}
	}

	CSelectThread *nt=new CSelectThread(WorkerThreadsPerMaster);
	nt->AddClient( client );

	SelectThreads.push_back( nt );

	Server->createThread(nt, "fastcgi: accept");
}

bool CAcceptThread::init_socket_v4(unsigned short port)
{
	int type = SOCK_STREAM;
#if !defined(_WIN32) && defined(SOCK_CLOEXEC)
	type |= SOCK_CLOEXEC;
#endif
	s = socket(AF_INET, type, 0);
	if (s < 1)
	{
		Server->Log("Creating SOCKET failed. Port " + convert((int)port) + " may already be in use", LL_ERROR);
		return false;
	}

	if (!prepareSocket(s))
	{
		closesocket(s);
		s = SOCKET_ERROR;
		return false;
	}

	sockaddr_in addr;

	memset(&addr, 0, sizeof(sockaddr_in));
	addr.sin_family = AF_INET;
	addr.sin_port = htons(port);
	addr.sin_addr.s_addr = htonl(INADDR_ANY);

	if (Server->getServerParameter("fastcgi_localhost_only") == "1")
	{
		addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
	}

	int rc = bind(s, (sockaddr*)&addr, sizeof(addr));
	if (rc == SOCKET_ERROR)
	{
		Server->Log("Failed binding SOCKET to Port " + convert(port), LL_ERROR);
		closesocket(s);
		s = SOCKET_ERROR;
		return false;
	}

	listen(s, 10000);
	return true;
}

bool CAcceptThread::init_socket_v6(unsigned short port)
{
	int type = SOCK_STREAM;
#if !defined(_WIN32) && defined(SOCK_CLOEXEC)
	type |= SOCK_CLOEXEC;
#endif
	s_v6 = socket(AF_INET6, type, 0);

	if (s_v6<1)
	{
		Server->Log("Creating ipv6 SOCKET failed. Port " + convert((int)port) + " may already be in use", LL_ERROR);
		return false;
	}

	if (!prepareSocket(s_v6))
	{
		closesocket(s_v6);
		s_v6 = SOCKET_ERROR;
		return false;
	}

	int optval = 1;
	setsockopt(s_v6, IPPROTO_IPV6, IPV6_V6ONLY, (char*)&optval, sizeof(optval));

	sockaddr_in6 addr = {};
	addr.sin6_family = AF_INET6;
	addr.sin6_port = htons(port);
	addr.sin6_addr = in6addr_any;

	if (Server->getServerParameter("fastcgi_localhost_only") == "1")
	{
		addr.sin6_addr = in6addr_loopback;
	}

	int rc = bind(s_v6, (sockaddr*)&addr, sizeof(addr));
	if (rc == SOCKET_ERROR)
	{
		Server->Log("Failed binding ipv6 SOCKET to Port " + convert(port), LL_ERROR);
		closesocket(s_v6);
		s_v6 = SOCKET_ERROR;
		return false;
	}

	listen(s_v6, 10000);

	return true;
}

bool CAcceptThread::has_error(void)
{
	return error;
}