/***************************************************************************
 *   Copyright (C) 03/2005 by Olaf Rempel                                  *
 *   razzor@kopf-tisch.de                                                  *
 *                                                                         *
 *   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 2 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, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#include <sys/ioctl.h>

#include "event.h"
#include "netpkt.h"
#include "configfile.h"
#include "plugin.h"
#include "scanner.h"
#include "logging.h"
#include "gamelist.h"

static LIST_HEAD(tx_queue);

static int scan_sock;

int pkt_send(struct in_addr *dstip, unsigned int dstport, char *buf, unsigned int size)
{
	struct net_pkt *pkt = malloc(sizeof(struct net_pkt) + size);
	if (pkt == NULL) {
		log_print(LOG_WARN, "pkt_send(): out of memory");
		return -1;
	}

	pkt->addr.sin_family = AF_INET;
	pkt->addr.sin_port = htons(dstport);
	pkt->addr.sin_addr.s_addr = (dstip ? dstip->s_addr : 0xFFFFFFFF);

	memcpy(pkt->buf, buf, size);
	pkt->size = size;

	list_add_tail(&pkt->list, &tx_queue);
	return 0;
}

static int scanner_transmit(void *privdata)
{
	if (list_empty(&tx_queue))
		return -1;

	struct net_pkt *pkt;
	pkt = list_entry(tx_queue.next, struct net_pkt, list);
	list_del(&pkt->list);

	int ret = sendto(scan_sock, pkt->buf, pkt->size, 0, (struct sockaddr *)&pkt->addr, sizeof(pkt->addr));
	if (ret <= 0)
		log_print(LOG_WARN, "scanner_transmit(): sendto()");

	return 0;
}

static int scanner_scan(void *privdata)
{
	plugins_scan();

	struct timeval tv;
	tv.tv_sec = 0;
	tv.tv_usec = 10000;

	event_add_timeout(&tv, scanner_transmit, NULL);
	return 0;
}

static int scanner_receive(int fd, void *privdata)
{
	int recvsize;
	if (ioctl(fd, FIONREAD, &recvsize) == -1) {
		log_print(LOG_WARN, "scanner_receive(): ioctl(FIONREAD)");
		return 0;
	}

	struct net_pkt *pkt = malloc(sizeof(struct net_pkt) + recvsize);
	if (pkt == NULL) {
		log_print(LOG_WARN, "scanner_receive(): out of memory");
		return 0;
	}

	unsigned int i = sizeof(struct sockaddr_in);
	pkt->size = recvfrom(fd, pkt->buf, recvsize, 0, (struct sockaddr *)&pkt->addr, &i);

	if (pkt->size < 0) {
		log_print(LOG_WARN, "scanner_receive(): recvfrom()");
		free(pkt);
		return 0;
	}

	switch (plugins_parse(pkt)) {
	case PARSE_REJECT: {
		char *pkt_str = pkt_print(pkt);
		log_print(LOG_INFO, "scanner_receive(): unknown packet: %s:%d size:%d\n%s",
			inet_ntoa(pkt->addr.sin_addr),
			ntohs(pkt->addr.sin_port),
			pkt->size, pkt_str);

		free(pkt_str);
	}

	case PARSE_ACCEPT:
		free(pkt);

	case PARSE_ACCEPT_FREED:
		break;
	}

	return 0;
}

int scanner_init()
{
	scan_sock = socket(PF_INET, SOCK_DGRAM, 0);
	if (scan_sock < 0) {
		log_print(LOG_ERROR, "scan_init(): socket()");
		return -1;
	}

	struct sockaddr_in src;
	char *addr = config_get_string("global", "scanner_src", "0.0.0.0:7130");
	if (parse_saddr(addr, &src) != 0) {
		log_print(LOG_ERROR, "server_init(): invalid scanner_src '%s'", addr);
		return -1;
	}

	if (bind(scan_sock, (struct sockaddr *)&src, sizeof(src)) < 0) {
		log_print(LOG_ERROR, "scan_init(): bind()");
		return -1;
	}

	int j = 1;
	if (setsockopt(scan_sock, SOL_SOCKET, SO_BROADCAST, &j, sizeof(j))) {
		log_print(LOG_ERROR, "scan_init(): setsockopt(SO_BROADCAST)");
		return -1;
	}

	int rxsize = 1<<20;
	if (setsockopt(scan_sock, SOL_SOCKET, SO_RCVBUF, &rxsize, sizeof(rxsize))) {
		log_print(LOG_ERROR, "scan_init(): setsockopt(SO_RCVBUF)");
		return -1;
	}

	event_add_readfd(scan_sock, scanner_receive, NULL);
	log_print(LOG_INFO, "scan socket initialized (%s:%d)", inet_ntoa(src.sin_addr), ntohs(src.sin_port));

	struct timeval tv;
	tv.tv_sec = config_get_int("global", "scan_interval", 60);
	tv.tv_usec = 0;

	event_add_timeout(&tv, scanner_scan, NULL);

	scanner_scan(NULL);
	return 0;
}