#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>

#include "intf.h"
#include "net-proxy.h"
#include "debug.h"

static int init_fd(struct tsnif_handle *h, struct tsnif_np_args *args, int server)
{
	struct tsnif_np_handle *nph = &h->np;
	struct sockaddr_in *sa = &args->sa;
	int fd;

	fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
	if (-1 == fd) {
		TSNIF_DEBUG(NP, "failed to create udp socket\n");
		return -1;
	}

	nph->fd_udp = fd;

	if (server) {
		if (-1 == bind(fd, sa, sizeof(*sa))) {
			close(fd);
			TSNIF_DEBUG(NP, "failed to bind\n");
			return -1;
		}
	}

	TSNIF_DEBUG(NP, "socket created %d\n", fd);
	return 0;
}

int udp_init_server(struct tsnif_handle *h, struct tsnif_np_args *args)
{
	TSNIF_DEBUG(NP, "creating server socket\n");
	return init_fd(h, args, 1);
}

int udp_init_client(struct tsnif_handle *h, struct tsnif_np_args *args)
{
	TSNIF_DEBUG(NP, "creating client socket\n");
	return init_fd(h, args, 0);
}

int udp_close(struct tsnif_handle *h)
{
	struct tsnif_np_handle *nph = &h->np;

	TSNIF_DEBUG(NP, "closing client socket\n");
	close(nph->fd_udp);
	return 0;
}

int udp_send(struct tsnif_handle *h, struct trans_msg *msg)
{
	struct tsnif_np_msg *m;
	struct tsnif_np_handle *nph = &h->np;
	int size = sizeof(*msg);

	TSNIF_DEBUG(NP, "sending cmd = %d\n", msg->cmd);

	if (TSNIF_CMD_DATA == msg->cmd)
		size += msg->data.len;

	m = malloc(size);
	if (!m)
		return -1;

	m->msg = *msg;

	if (TSNIF_CMD_DATA == msg->cmd)
		memcpy(m->data, msg->data.ptr, msg->data.len);

	if (TSNIF_NP_UDP_SERVER & TSNIF_NP_FLAGS(nph))
		return sendto(nph->fd_udp, m, size, 0,
			      &nph->udp_client.sa, sizeof(nph->udp_client.sa));

	return sendto(nph->fd_udp, m, size, 0,
			&nph->args->sa, sizeof(nph->args->sa));
}

int udp_process(struct tsnif_handle *h)
{
	struct tsnif_np_handle *nph = &h->np;
	struct trans_msg msg;
	char *data = NULL;
	int ret;
	struct sockaddr_in sa;
	socklen_t sl = sizeof(sa);

	ret = recvfrom(nph->fd_udp, &msg, sizeof(msg), 0,
		       &sa, &sl);
	if (ret <= 0)
		return ret;

	/* just one client supported for now */
	if (memcmp(&nph->udp_client.sa, &sa, sizeof(sa))) {
		TSNIF_DEBUG(NP, "got new client\n");
		memset(&nph->udp_client, 0x0, sizeof(nph->udp_client));
		nph->udp_client.sa = sa;
		nph->udp_client.connected = 1;
	}

	/* receive the data part */
	if (TSNIF_CMD_DATA == msg.cmd) {

		/* XXX some size check would be nice.. */
		data = malloc(msg.data.len);
		if (!data)
			return -1;

		ret = recvfrom(nph->fd_udp, data, msg.data.len, 0,
			       &sa, &sl);
		if (ret <= 0) {
			free(data);
			return ret;
		}

		msg.data.ptr = data;
	}

	ret = tsnif_np_dispatch(h, &msg);

	if (data)
		free(data);

	return ret;
}

struct tsnif_np_prot udp_prot = {
	.init_server = udp_init_server,
	.init_client = udp_init_client,
	.close       = udp_close,
	.send        = udp_send,
	.process     = udp_process,
};