#include "config.h"
#include <assert.h>
#include <pcap.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/types.h>

#include <netinet/in.h>

#include <linux/if_arp.h>
#include <linux/if_ether.h>
#include <linux/if_packet.h>

#include "test_module.h"
#include "utils.h"


/***********************************************************************
 * hook for the test module to signal that the test is done
 **/

int oflops_end_test(struct oflops_context *ctx,int should_continue)
{
	ctx->should_end = 1;
	ctx->should_continue = should_continue;
	return 0;
}

/**********************************************************************
 * hook for the test module to get access to a raw file descriptor bound
 * 	to the data channel's device
 **/

int oflops_get_channel_raw_fd(struct oflops_context * ctx, oflops_channel_name ch)
{
	struct ifreq ifr;
	struct sockaddr_ll saddrll;
	struct channel_info * ch_info;
	if(ch >= ctx->n_channels)
		return -1;	// no such channel
	ch_info = &ctx->channels[ch];
	if(ch_info->raw_sock != -1)	// already allocated?
		return ch_info->raw_sock;
	// else, setup raw socket
	ch_info->raw_sock = socket(AF_PACKET,SOCK_RAW, htons(ETH_P_ALL));
	if( ch_info->raw_sock == -1)
		perror_and_exit("raw socket(AF_PACKET,SOCK_RAW,htons(ETH_P_ALL))",1);
	// bind to a specific port
	strncpy(ifr.ifr_name,ch_info->dev,IFNAMSIZ);
	if( ioctl( ch_info->raw_sock, SIOCGIFINDEX, &ifr)  == -1 )
		perror_and_exit("ioctl()",1);
	memset(&saddrll, 0, sizeof(saddrll));
	saddrll.sll_family = AF_PACKET;
	saddrll.sll_protocol = ETH_P_ALL;
	saddrll.sll_ifindex = ifr.ifr_ifindex;
	if ( bind(ch_info->raw_sock, (struct sockaddr *) &saddrll, sizeof(struct sockaddr_ll)) == -1 )
		perror_and_exit("bind()",1);
	return ch_info->raw_sock;
}

/**********************************************************************
 * hook for the test module to get access to a udp file descriptor bound
 * 	to the data channel's device
 **/
int oflops_get_channel_fd(struct oflops_context * ctx, oflops_channel_name ch)
{
	struct ifreq ifr;
	struct channel_info * ch_info;
	if(ch >= ctx->n_channels)
		return -1;	// no such channel
	ch_info = &ctx->channels[ch];
	if(ch_info->sock != -1)	// already allocated?
		return ch_info->sock;
	// else, setup raw socket
	ch_info->sock = socket(AF_INET,SOCK_DGRAM,0);	// UDP socket
	if( ch_info->sock == -1)
		perror_and_exit("udp socket(AF_INET,SOCK_DGRAM,0)",1);
	// bind to a specific port
	strncpy(ifr.ifr_name,ch_info->dev,IFNAMSIZ);
	if( ioctl( ch_info->sock, SIOCGIFINDEX, &ifr)  == -1 )
		perror_and_exit("ioctl() bind to dev",1);
	return ch_info->sock;
}

/***************************************************************************
 * hook for the test module to schedule an timer_event to be called back into the module
 **/

int oflops_schedule_timer_event(struct oflops_context *ctx, struct timeval *tv, void * arg)
{
	return wc_event_add(ctx->timers, NULL, arg, *tv);
}


/*****************************************************************************
 * hook for the test module to send an openflow mesgs across the control channel 
 * 	to the switch
 * 	FIXME: assert()'s that the message doesn't block -- if this is a problem
 * 	we need to implement some buffering and mod the select() call to open for
 * 	writing
 **/
size_t oflops_send_of_mesgs(struct oflops_context *ctx, char * buf, size_t buflen)
{
	msgbuf_push(ctx->control_outgoing, buf, buflen);
    return buflen;
}
/*****************************************************************************
 * hook for the test module to send an openflow mesg across the control channel 
 * 	to the switch
 * 	FIXME: assert()'s that the message doesn't block -- if this is a problem
 * 	we need to implement some buffering and mod the select() call to open for
 * 	writing
 **/
int oflops_send_of_mesg(struct oflops_context *ctx, struct ofp_header * ofph)
{
	int len = ntohs(ofph->length);

	msgbuf_push(ctx->control_outgoing, (void *) ofph, len);
	return len;
}

/********************************************************************************
 * hook for the test module to send a raw message out a certain data channel
 * 	here, "raw" means with ethernet header
 **/

int oflops_send_raw_mesg(struct oflops_context *ctx, oflops_channel_name ch, void * msg, int len)
{
	struct sockaddr_ll socket_address;
	int ret;
	oflops_get_channel_raw_fd(ctx,ch);  // ensure that a raw sock is allocated

	ctx->channels[ch].packet_len = len;

	bzero(&socket_address,sizeof(socket_address));
	socket_address.sll_family   = PF_PACKET;
	socket_address.sll_protocol = htons(ETH_P_ALL);
	/*index of the network device
	 *          * see full code later how to retrieve it*/
	socket_address.sll_ifindex  = ctx->channels[ch].ifindex;
	/********************* do we need any of this? */
	socket_address.sll_hatype   = ARPHRD_ETHER; //don't need?
	socket_address.sll_halen    = ETH_ALEN;
	socket_address.sll_pkttype  = PACKET_OTHERHOST;
	//*/
	
	/*queue the packet*/
	ret = write( ctx->channels[ch].raw_sock, msg, len);
	//msgbuf_push(ctx->channels[ch].outgoing, msg, len);
	//send_result = sendto(sock, msg, len, 0,  ***** old code
	//		     (struct sockaddr*)&socket_address, sizeof(socket_address));
	//	sendto(ctx->channels[ch].raw_sock, msg, len, 0, 
	//(struct sockaddr*)&socket_address, sizeof(socket_address));
        if ( ret < 0 && errno != ENOBUFS ) {
	  fprintf(stderr, "sending of data failed\n");
        }
	
	return len;;
}

/**************************************************************************************
 * hook to get high accuracy pcap timestamp for this data
 * @return zero if not found, one if found
 **/
int oflops_get_timestamp(struct oflops_context * ctx, void * data, int len, struct pcap_pkthdr * hdr, oflops_channel_name ofc)
{
	channel_info * ch  = &ctx->channels[ofc];
	if(ch->timestamps == NULL)
        return 0;       // not requested
	return ptrack_lookup(ch->timestamps,data,len,hdr);
}

int oflops_snmp_get(struct oflops_context * ctx, oid query[], size_t len)
{
	struct snmp_channel* ch = ctx->snmp_channel_info;
	struct snmp_session* sess;

	//Open session for async request
	if(!(sess = snmp_open(&(ch->session))))
	{
		snmp_perror("snmp_open");
		return 1;
	}

	//Build and send packet
	if (ch->req != NULL)
		snmp_free_pdu(ch->req);
	ch->req = snmp_pdu_create(SNMP_MSG_GET);
	snmp_add_null_var(ch->req, query, len);
	if (!snmp_send(sess, ch->req))
		snmp_perror("snmp_send");

	return 0;
}