/*
 * Copyright (c) 2012 Jiri Svoboda
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup loopip
 * @{
 */
/**
 * @file
 * @brief Loopback IP link provider
 */

#include <adt/prodcons.h>
#include <async.h>
#include <errno.h>
#include <str_error.h>
#include <inet/iplink_srv.h>
#include <inet/addr.h>
#include <io/log.h>
#include <loc.h>
#include <stdio.h>
#include <stdlib.h>
#include <str.h>
#include <task.h>

#define NAME  "loopip"

static errno_t loopip_open(iplink_srv_t *srv);
static errno_t loopip_close(iplink_srv_t *srv);
static errno_t loopip_send(iplink_srv_t *srv, iplink_sdu_t *sdu);
static errno_t loopip_send6(iplink_srv_t *srv, iplink_sdu6_t *sdu);
static errno_t loopip_get_mtu(iplink_srv_t *srv, size_t *mtu);
static errno_t loopip_get_mac48(iplink_srv_t *srv, addr48_t *mac);
static errno_t loopip_addr_add(iplink_srv_t *srv, inet_addr_t *addr);
static errno_t loopip_addr_remove(iplink_srv_t *srv, inet_addr_t *addr);

static void loopip_client_conn(ipc_callid_t iid, ipc_call_t *icall, void *arg);

static iplink_ops_t loopip_iplink_ops = {
	.open = loopip_open,
	.close = loopip_close,
	.send = loopip_send,
	.send6 = loopip_send6,
	.get_mtu = loopip_get_mtu,
	.get_mac48 = loopip_get_mac48,
	.addr_add = loopip_addr_add,
	.addr_remove = loopip_addr_remove
};

static iplink_srv_t loopip_iplink;
static prodcons_t loopip_rcv_queue;

typedef struct {
	link_t link;

	/* XXX Version should be part of SDU */
	ip_ver_t ver;
	iplink_recv_sdu_t sdu;
} rqueue_entry_t;

static errno_t loopip_recv_fibril(void *arg)
{
	while (true) {
		log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_recv_fibril(): Wait for one item");
		link_t *link = prodcons_consume(&loopip_rcv_queue);
		rqueue_entry_t *rqe =
		    list_get_instance(link, rqueue_entry_t, link);

		(void) iplink_ev_recv(&loopip_iplink, &rqe->sdu, rqe->ver);

		free(rqe->sdu.data);
		free(rqe);
	}

	return 0;
}

static errno_t loopip_init(void)
{
	async_set_fallback_port_handler(loopip_client_conn, NULL);

	errno_t rc = loc_server_register(NAME);
	if (rc != EOK) {
		log_msg(LOG_DEFAULT, LVL_ERROR, "Failed registering server.");
		return rc;
	}

	iplink_srv_init(&loopip_iplink);
	loopip_iplink.ops = &loopip_iplink_ops;
	loopip_iplink.arg = NULL;

	prodcons_initialize(&loopip_rcv_queue);

	const char *svc_name = "net/loopback";
	service_id_t sid;
	rc = loc_service_register(svc_name, &sid);
	if (rc != EOK) {
		log_msg(LOG_DEFAULT, LVL_ERROR, "Failed registering service %s.",
		    svc_name);
		return rc;
	}

	category_id_t iplink_cat;
	rc = loc_category_get_id("iplink", &iplink_cat, IPC_FLAG_BLOCKING);
	if (rc != EOK) {
		log_msg(LOG_DEFAULT, LVL_ERROR, "Failed resolving category 'iplink'.");
		return rc;
	}

	rc = loc_service_add_to_cat(sid, iplink_cat);
	if (rc != EOK) {
		log_msg(LOG_DEFAULT, LVL_ERROR, "Failed adding %s to category.",
		    svc_name);
		return rc;
	}

	fid_t fid = fibril_create(loopip_recv_fibril, NULL);
	if (fid == 0)
		return ENOMEM;

	fibril_add_ready(fid);

	return EOK;
}

static void loopip_client_conn(ipc_callid_t iid, ipc_call_t *icall, void *arg)
{
	log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_client_conn()");
	iplink_conn(iid, icall, &loopip_iplink);
}

static errno_t loopip_open(iplink_srv_t *srv)
{
	log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_open()");
	return EOK;
}

static errno_t loopip_close(iplink_srv_t *srv)
{
	log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_close()");
	return EOK;
}

static errno_t loopip_send(iplink_srv_t *srv, iplink_sdu_t *sdu)
{
	log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_send()");

	rqueue_entry_t *rqe = calloc(1, sizeof(rqueue_entry_t));
	if (rqe == NULL)
		return ENOMEM;

	/*
	 * Clone SDU
	 */
	rqe->ver = ip_v4;
	rqe->sdu.data = malloc(sdu->size);
	if (rqe->sdu.data == NULL) {
		free(rqe);
		return ENOMEM;
	}

	memcpy(rqe->sdu.data, sdu->data, sdu->size);
	rqe->sdu.size = sdu->size;

	/*
	 * Insert to receive queue
	 */
	prodcons_produce(&loopip_rcv_queue, &rqe->link);

	return EOK;
}

static errno_t loopip_send6(iplink_srv_t *srv, iplink_sdu6_t *sdu)
{
	log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip6_send()");

	rqueue_entry_t *rqe = calloc(1, sizeof(rqueue_entry_t));
	if (rqe == NULL)
		return ENOMEM;

	/*
	 * Clone SDU
	 */
	rqe->ver = ip_v6;
	rqe->sdu.data = malloc(sdu->size);
	if (rqe->sdu.data == NULL) {
		free(rqe);
		return ENOMEM;
	}

	memcpy(rqe->sdu.data, sdu->data, sdu->size);
	rqe->sdu.size = sdu->size;

	/*
	 * Insert to receive queue
	 */
	prodcons_produce(&loopip_rcv_queue, &rqe->link);

	return EOK;
}

static errno_t loopip_get_mtu(iplink_srv_t *srv, size_t *mtu)
{
	log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_get_mtu()");
	*mtu = 1500;
	return EOK;
}

static errno_t loopip_get_mac48(iplink_srv_t *src, addr48_t *mac)
{
	log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_get_mac48()");
	return ENOTSUP;
}

static errno_t loopip_addr_add(iplink_srv_t *srv, inet_addr_t *addr)
{
	return EOK;
}

static errno_t loopip_addr_remove(iplink_srv_t *srv, inet_addr_t *addr)
{
	return EOK;
}

int main(int argc, char *argv[])
{
	printf("%s: HelenOS loopback IP link provider\n", NAME);

	errno_t rc = log_init(NAME);
	if (rc != EOK) {
		printf("%s: Failed to initialize logging: %s.\n", NAME, str_error(rc));
		return rc;
	}

	rc = loopip_init();
	if (rc != EOK) {
		printf("%s: Failed to initialize loopip: %s.\n", NAME, str_error(rc));
		return rc;
	}

	printf("%s: Accepting connections.\n", NAME);
	task_retval(0);
	async_manager();

	/* Not reached */
	return 0;
}

/** @}
 */