/*
	(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, version 3.

	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 wanaddr[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

#if MINIUPNPC_API_VERSION < 18
	ret = UPNP_GetValidIGD(devlist, &urls, &data, lanaddr, sizeof(lanaddr));
#else
	ret = UPNP_GetValidIGD(devlist, &urls, &data, lanaddr, sizeof(lanaddr), wanaddr, sizeof(wanaddr));
#endif
	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