#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include "logging.h"
#include "multisock.h"

#define DEFAULT_PORT 7130

#define DEVFILE "/proc/net/dev"
#define BUFSIZE 256


MultiSock::Socket::Socket()
{
	if ((fd = socket(PF_INET, SOCK_DGRAM, 0)) < 0)
		LogSystem::log(LOG_CRIT, "Socket: socket()");
}

MultiSock::Socket::~Socket()
{
	close(fd);
}

bool MultiSock::Socket::bindToDevice(const char* name)
{
	strncpy(devname, name, sizeof(devname));
	
	int ret = setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, devname, sizeof(devname));

	if (ret < 0) {
		LogSystem::log(LOG_WARNING, "Socket: setsockopt(SO_BINDTODEVICE) %s", devname);
		return false;
	}

	return true;
}

bool MultiSock::Socket::bindToPort(int port)
{
	struct ifreq ifr;
	
	strncpy(ifr.ifr_name, devname, sizeof(ifr.ifr_name));
	
	if (ioctl(fd, SIOCGIFADDR, &ifr) != 0) {
		LogSystem::log(LOG_WARNING, "Socket: ioctl(SIOCGIFADDR) %s", devname);
		return false;
	}
	
	memcpy(&addr, &ifr.ifr_addr, sizeof(addr));
	addr.sin_port = htons(port);

	if (bind(fd, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
		LogSystem::log(LOG_WARNING, "Socket: bind() %s", devname);
		return false;
	}

	int bcast = 1;
	if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &bcast, sizeof(bcast))) {
		LogSystem::log(LOG_WARNING, "Socket: setsockopt(SO_BROADCAST) %s", devname);
		return false;
	}

	return true;
}


int MultiSock::Socket::show(char* buf, int size)
{
	return snprintf(buf, size, "%s (%s:%d) ", devname,
		inet_ntoa(addr.sin_addr), ntohs(addr.sin_port));
}

MultiSock::Socket* MultiSock::Socket::createSocket(const char* name, int port)
{
	Socket* sock = new Socket();
	
	if (sock->fd < 0) {
		delete sock;
		return NULL;
	}
	
	struct ifreq ifr;
	strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));

	if (ioctl(sock->fd, SIOCGIFFLAGS, &ifr) != 0) {
		LogSystem::log(LOG_WARNING, "Socket: ioctl(SIOCGIFFLAGS) %s", name);
		delete sock;
		return NULL;
	}

	if (!(ifr.ifr_flags & IFF_UP) || (ifr.ifr_flags & (IFF_LOOPBACK | IFF_POINTOPOINT))) {
		delete sock;
		return NULL;
	}

	sock->bindToDevice(name);
	
	if (!sock->bindToPort(port)) {
		delete sock;
		return NULL;
	}
	
	return sock;
}


MultiSock::MultiSock(Config& conf)
{
	char* buf = (char*)malloc(BUFSIZE);
	if (buf == NULL) {
		LogSystem::log(LOG_CRIT, "MultiSock(): out of memory");
		return;
	}

	FILE* fp = fopen(DEVFILE, "r");
	if (fp == NULL) {
		LogSystem::log(LOG_CRIT, "MultiSock(): can not open " DEVFILE);
		free(buf);
		return;
	}
	
	fgets(buf, BUFSIZE, fp);
	fgets(buf, BUFSIZE, fp);
	
	int port = conf.getInteger("global", "scan_port", DEFAULT_PORT);
	FD_ZERO(&fdsel);

	while (fgets(buf, BUFSIZE, fp) != NULL) {
		char* tok = strtok(buf, " :");

		// TODO: check against config list
		
		Socket* sock = Socket::createSocket(tok, port);
		if (sock) {
			FD_SET(sock->getFD(), &fdsel);
			
			sock->show(buf, BUFSIZE);
			LogSystem::log(LOG_NOTICE, "adding Interface %s", buf);
			
			ifaceList.add(sock);
		}
	}

	fclose(fp);
	free(buf);
}

MultiSock::~MultiSock()
{
	while (!ifaceList.isEmpty())
		delete ifaceList.get();
}


int MultiSock::getRecvSocket()
{
	fd_set fdcpy;

	while (1) {
		memcpy(&fdcpy, &fdsel, sizeof(fdcpy));

		select(FD_SETSIZE, &fdcpy, NULL, NULL, NULL);
		
		Iterator<Socket>* it = ifaceList.createIterator();
		while (it->hasNext()) {
			Socket* sock = it->next();
			if (FD_ISSET(sock->getFD(), &fdcpy)) {
				delete it;
				return sock->getFD();
			}
		}
		delete it;

		LogSystem::log(LOG_ERROR, "getRecvSocket(): select()");
	}

	return -1;
}