/*
	(c) Copyright  2012 - 2018 Anton Sviridenko
	https://picapica.im

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU 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 General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/
#include "PICA_netconf.h"
#include <stddef.h>

#ifdef HAVE_LIBMINIUPNPC
#include <miniupnpc/miniupnpc.h>
#include <miniupnpc/miniwget.h>
#include <miniupnpc/upnpcommands.h>
#include <miniupnpc/upnperrors.h>
#include <stdio.h>
#endif

#ifndef WIN32
#include <sys/types.h>
#include <ifaddrs.h>
#include <net/if.h>
#endif

#define PREFIX4   htonl(0xf0000000U)
#define PREFIX8   htonl(0xff000000U)
#define PREFIX12 htonl(0xfff00000U)
#define PREFIX16 htonl(0xffff0000U)
#define PREFIX24 htonl(0xffffff00U)

#define MAKEIP(a, b, c, d) (htonl( (a&0xFF) << 24 | (b&0xFF) << 16 | (c&0xFF) << 8 | (d&0xFF) ))


int PICA_is_reserved_addr_ipv4(in_addr_t addr)
{
	if ((addr & PREFIX8)  == 0 //0.0.0.0/8
	        ||  (addr & PREFIX8)  == MAKEIP(10, 0, 0, 0) //10.0.0.0/8
	        ||  (addr & PREFIX8)  == MAKEIP(127, 0, 0, 0)//127.0.0.0/8
	        ||  (addr & PREFIX16) == MAKEIP(169, 254, 0, 0) //169.254.0.0/16
	        ||  (addr & PREFIX12) == MAKEIP(172, 16, 0, 0) //172.16.0.0/12
	        ||  (addr & PREFIX16) == MAKEIP(192, 168, 0, 0) //192.168.0.0/16
	        ||  (addr & PREFIX4)  == MAKEIP(224, 0, 0, 0) //224.0.0.0/4
	        ||  (addr & PREFIX4)  == MAKEIP(240, 0, 0, 0) //240.0.0.0/4
	        ||   addr == INADDR_BROADCAST
	   )
		return 1;

	return 0;
}

in_addr_t PICA_guess_listening_addr_ipv4()
{
	in_addr_t retaddr = INADDR_ANY;
	int found_global = 0;
#ifndef WIN32
	struct ifaddrs *ifaddr, *ifa;

	if (getifaddrs(&ifaddr) == -1)
		return INADDR_ANY;

	for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next)
	{
		if (ifa->ifa_addr == NULL)
			continue;

		if (ifa->ifa_addr->sa_family != AF_INET)
			continue;

		if (ifa->ifa_flags & IFF_LOOPBACK)
			continue;

		if (!((ifa->ifa_flags & IFF_RUNNING) && (ifa->ifa_flags & IFF_UP)))
			continue;

		if (!found_global)
		{
			retaddr = ((struct sockaddr_in*)ifa->ifa_addr)->sin_addr.s_addr;

			if (!PICA_is_reserved_addr_ipv4(retaddr))
				found_global = 1;
		}
	}

	freeifaddrs(ifaddr);
#else
	char databuf[16384];
	ULONG size = sizeof databuf;
	ULONG ret;
	PIP_ADAPTER_ADDRESSES addrs = (PIP_ADAPTER_ADDRESSES)databuf;
	PIP_ADAPTER_ADDRESSES ap;

	ret = GetAdaptersAddresses(AF_INET,
		GAA_FLAG_SKIP_ANYCAST
		| GAA_FLAG_SKIP_MULTICAST
		| GAA_FLAG_SKIP_DNS_SERVER
		| GAA_FLAG_SKIP_FRIENDLY_NAME,
		NULL,
		addrs, &size);

	if (ret != NO_ERROR)
		return INADDR_ANY;

	ap = addrs;
	while(ap)
	{
		retaddr = ((struct sockaddr_in*)ap->FirstUnicastAddress->Address.lpSockaddr)->sin_addr.s_addr;
		if (!PICA_is_reserved_addr_ipv4(retaddr))
			break;
		ap = ap->Next;
	}

#endif
	return retaddr;
}

#ifdef HAVE_LIBMINIUPNPC
int PICA_upnp_autoconfigure_ipv4(int public_port, int local_port, char *public_ip)
{
	struct UPNPDev *devlist = NULL;
	int error = 0;
	struct UPNPUrls urls;
	struct IGDdatas data;
	char lanaddr[64];
	char ppstr[8];
	char lpstr[8];
	int ret;

#if MINIUPNPC_API_VERSION < 14
	devlist = upnpDiscover(2000, 0, 0, 0, 0, &error);
#else
	devlist = upnpDiscover(2000, 0, 0, 0, 0, 2, &error);
#endif


	ret = UPNP_GetValidIGD(devlist, &urls, &data, lanaddr, sizeof(lanaddr));

	if (ret != 1)
	{
		freeUPNPDevlist(devlist);
		return 0;
	}

	ret = UPNP_GetExternalIPAddress(urls.controlURL, data.first.servicetype, public_ip);

	if (ret != UPNPCOMMAND_SUCCESS)
	{
		freeUPNPDevlist(devlist);
	        FreeUPNPUrls(&urls);
		return 0;
	}

	sprintf(ppstr, "%u", public_port);
	sprintf(lpstr, "%u", local_port);

	ret = UPNP_AddPortMapping(urls.controlURL, data.first.servicetype,
					ppstr, lpstr, lanaddr, "Pica Pica", "TCP", 0, "0");


	if (ret != UPNPCOMMAND_SUCCESS)
		ret = 0;
	else
		ret = 1;

	freeUPNPDevlist(devlist);
	FreeUPNPUrls(&urls);
	return ret;
}
#endif