/* A Media Gateway Control Protocol Media Gateway: RFC 3435 */
/* rate-counter implementation */

/*
 * (C) 2009-2012 by Holger Hans Peter Freyther <zecke@selfish.org>
 * (C) 2009-2012 by On-Waves
 * (C) 2017-2020 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
 * All Rights Reserved
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation; either version 3 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#include <errno.h>
#include <osmocom/core/stats.h>
#include <osmocom/mgcp/mgcp_internal.h>
#include <osmocom/mgcp/mgcp_ratectr.h>

static const struct rate_ctr_desc mgcp_general_ctr_desc[] = {
	/* rx_msgs = rx_msgs_retransmitted + rx_msgs_handled + rx_msgs_unhandled + err_rx_msg_parse + err_rx_no_endpoint */
	[MGCP_GENERAL_RX_MSGS_TOTAL] = { "mgcp:rx_msgs", "total number of MGCP messages received." },
	[MGCP_GENERAL_RX_MSGS_RETRANSMITTED] = { "mgcp:rx_msgs_retransmitted", "number of received retransmissions." },
	[MGCP_GENERAL_RX_MSGS_HANDLED] = { "mgcp:rx_msgs_handled", "number of handled MGCP messages." },
	[MGCP_GENERAL_RX_MSGS_UNHANDLED] = { "mgcp:rx_msgs_unhandled", "number of unhandled MGCP messages." },
	[MGCP_GENERAL_RX_FAIL_MSG_PARSE] = { "mgcp:err_rx_msg_parse", "error parsing MGCP message." },
	[MGCP_GENERAL_RX_FAIL_NO_ENDPOINT] =
	    { "mgcp:err_rx_no_endpoint", "can't find MGCP endpoint, probably we've used all allocated endpoints." },
};

const static struct rate_ctr_group_desc mgcp_general_ctr_group_desc = {
	.group_name_prefix = "mgcp",
	.group_description = "mgcp general statistics",
	.class_id = OSMO_STATS_CLASS_GLOBAL,
	.num_ctr = ARRAY_SIZE(mgcp_general_ctr_desc),
	.ctr_desc = mgcp_general_ctr_desc
};

static const struct rate_ctr_desc mgcp_crcx_ctr_desc[] = {
	[MGCP_CRCX_SUCCESS] = { "crcx:success", "CRCX command processed successfully." },
	[MGCP_CRCX_FAIL_BAD_ACTION] = { "crcx:bad_action", "bad action in CRCX command." },
	[MGCP_CRCX_FAIL_UNHANDLED_PARAM] = { "crcx:unhandled_param", "unhandled parameter in CRCX command." },
	[MGCP_CRCX_FAIL_MISSING_CALLID] = { "crcx:missing_callid", "missing CallId in CRCX command." },
	[MGCP_CRCX_FAIL_INVALID_MODE] = { "crcx:invalid_mode", "invalid connection mode in CRCX command." },
	[MGCP_CRCX_FAIL_LIMIT_EXCEEDED] = { "crcx:limit_exceeded", "limit of concurrent connections was reached." },
	[MGCP_CRCX_FAIL_UNKNOWN_CALLID] = { "crcx:unkown_callid", "unknown CallId in CRCX command." },
	[MGCP_CRCX_FAIL_ALLOC_CONN] = { "crcx:alloc_conn_fail", "connection allocation failure." },
	[MGCP_CRCX_FAIL_NO_REMOTE_CONN_DESC] =
	    { "crcx:no_remote_conn_desc", "no opposite end specified for connection." },
	[MGCP_CRCX_FAIL_START_RTP] = { "crcx:start_rtp_failure", "failure to start RTP processing." },
	[MGCP_CRCX_FAIL_REJECTED_BY_POLICY] = { "crcx:conn_rejected", "connection rejected by policy." },
	[MGCP_CRCX_FAIL_NO_OSMUX] = { "crcx:no_osmux", "no osmux offered by peer." },
	[MGCP_CRCX_FAIL_INVALID_CONN_OPTIONS] = { "crcx:conn_opt", "connection options invalid." },
	[MGCP_CRCX_FAIL_CODEC_NEGOTIATION] = { "crcx:codec_nego", "codec negotiation failure." },
	[MGCP_CRCX_FAIL_BIND_PORT] = { "crcx:bind_port", "port bind failure." },
};

const static struct rate_ctr_group_desc mgcp_crcx_ctr_group_desc = {
	.group_name_prefix = "crcx",
	.group_description = "crxc statistics",
	.class_id = OSMO_STATS_CLASS_GLOBAL,
	.num_ctr = ARRAY_SIZE(mgcp_crcx_ctr_desc),
	.ctr_desc = mgcp_crcx_ctr_desc
};

static const struct rate_ctr_desc mgcp_mdcx_ctr_desc[] = {
	[MGCP_MDCX_SUCCESS] = { "mdcx:success", "MDCX command processed successfully." },
	[MGCP_MDCX_FAIL_WILDCARD] = { "mdcx:wildcard", "wildcard endpoint names in MDCX commands are unsupported." },
	[MGCP_MDCX_FAIL_NO_CONN] = { "mdcx:no_conn", "endpoint specified in MDCX command has no active connections." },
	[MGCP_MDCX_FAIL_INVALID_CALLID] = { "mdcx:callid", "invalid CallId specified in MDCX command." },
	[MGCP_MDCX_FAIL_INVALID_CONNID] = { "mdcx:connid", "invalid connection ID specified in MDCX command." },
	[MGCP_MDCX_FAIL_UNHANDLED_PARAM] = { "crcx:unhandled_param", "unhandled parameter in MDCX command." },
	[MGCP_MDCX_FAIL_NO_CONNID] = { "mdcx:no_connid", "no connection ID specified in MDCX command." },
	[MGCP_MDCX_FAIL_CONN_NOT_FOUND] =
	    { "mdcx:conn_not_found", "connection specified in MDCX command does not exist." },
	[MGCP_MDCX_FAIL_INVALID_MODE] = { "mdcx:invalid_mode", "invalid connection mode in MDCX command." },
	[MGCP_MDCX_FAIL_INVALID_CONN_OPTIONS] = { "mdcx:conn_opt", "connection options invalid." },
	[MGCP_MDCX_FAIL_NO_REMOTE_CONN_DESC] =
	    { "mdcx:no_remote_conn_desc", "no opposite end specified for connection." },
	[MGCP_MDCX_FAIL_START_RTP] = { "mdcx:start_rtp_failure", "failure to start RTP processing." },
	[MGCP_MDCX_FAIL_REJECTED_BY_POLICY] = { "mdcx:conn_rejected", "connection rejected by policy." },
	[MGCP_MDCX_DEFERRED_BY_POLICY] = { "mdcx:conn_deferred", "connection deferred by policy." },
};

const static struct rate_ctr_group_desc mgcp_mdcx_ctr_group_desc = {
	.group_name_prefix = "mdcx",
	.group_description = "mdcx statistics",
	.class_id = OSMO_STATS_CLASS_GLOBAL,
	.num_ctr = ARRAY_SIZE(mgcp_mdcx_ctr_desc),
	.ctr_desc = mgcp_mdcx_ctr_desc
};

static const struct rate_ctr_desc mgcp_dlcx_ctr_desc[] = {
	[MGCP_DLCX_SUCCESS] = { "dlcx:success", "DLCX command processed successfully." },
	[MGCP_DLCX_FAIL_WILDCARD] = { "dlcx:wildcard", "wildcard names in DLCX commands are unsupported." },
	[MGCP_DLCX_FAIL_NO_CONN] = { "dlcx:no_conn", "endpoint specified in DLCX command has no active connections." },
	[MGCP_DLCX_FAIL_INVALID_CALLID] =
	    { "dlcx:callid", "CallId specified in DLCX command mismatches endpoint's CallId ." },
	[MGCP_DLCX_FAIL_INVALID_CONNID] =
	    { "dlcx:connid", "connection ID specified in DLCX command does not exist on endpoint." },
	[MGCP_DLCX_FAIL_UNHANDLED_PARAM] = { "dlcx:unhandled_param", "unhandled parameter in DLCX command." },
	[MGCP_DLCX_FAIL_REJECTED_BY_POLICY] = { "dlcx:rejected", "connection deletion rejected by policy." },
	[MGCP_DLCX_DEFERRED_BY_POLICY] = { "dlcx:deferred", "connection deletion deferred by policy." },
};

const static struct rate_ctr_group_desc mgcp_dlcx_ctr_group_desc = {
	.group_name_prefix = "dlcx",
	.group_description = "dlcx statistics",
	.class_id = OSMO_STATS_CLASS_GLOBAL,
	.num_ctr = ARRAY_SIZE(mgcp_dlcx_ctr_desc),
	.ctr_desc = mgcp_dlcx_ctr_desc
};

const static struct rate_ctr_group_desc all_rtp_conn_rate_ctr_group_desc = {
	.group_name_prefix = "all_rtp_conn",
	.group_description = "aggregated statistics for all rtp connections",
	.class_id = 1,
	.num_ctr = ARRAY_SIZE(all_rtp_conn_rate_ctr_desc),
	.ctr_desc = all_rtp_conn_rate_ctr_desc
};

static int free_rate_counter_group(struct rate_ctr_group *rate_ctr_group)
{
	rate_ctr_group_free(rate_ctr_group);
	return 0;
}

/*! allocate global rate counters into a given rate counter struct
 *  (called once at startup)
 *  \param[in] ctx talloc context.
 *  \param[out] ratectr struct that holds the counters
 *  \returns 0 on success, -EINVAL on failure */
int mgcp_ratectr_global_alloc(void *ctx, struct mgcp_ratectr_global *ratectr)
{
	/* FIXME: Each new rate counter group requires a unique index. At the
	 * moment we generate an index using a counter, but perhaps there is
	 * a better way of assigning indices? */
	static unsigned int general_rate_ctr_index = 0;

	if (ratectr->mgcp_general_ctr_group == NULL) {
		ratectr->mgcp_general_ctr_group =
		    rate_ctr_group_alloc(ctx, &mgcp_general_ctr_group_desc, general_rate_ctr_index);
		if (!ratectr->mgcp_general_ctr_group)
			return -EINVAL;
		talloc_set_destructor(ratectr->mgcp_general_ctr_group, free_rate_counter_group);
		general_rate_ctr_index++;
	}
	return 0;
}

/*! allocate trunk specific rate counters into a given rate counter struct
 *  (called once on trunk initialization)
 *  \param[in] ctx talloc context.
 *  \param[out] ratectr struct that holds the counters
 *  \returns 0 on success, -EINVAL on failure */
int mgcp_ratectr_trunk_alloc(void *ctx, struct mgcp_ratectr_trunk *ratectr)
{
	/* FIXME: see comment in mgcp_ratectr_global_alloc()  */
	static unsigned int crcx_rate_ctr_index = 0;
	static unsigned int mdcx_rate_ctr_index = 0;
	static unsigned int dlcx_rate_ctr_index = 0;
	static unsigned int all_rtp_conn_rate_ctr_index = 0;

	if (ratectr->mgcp_crcx_ctr_group == NULL) {
		ratectr->mgcp_crcx_ctr_group = rate_ctr_group_alloc(ctx, &mgcp_crcx_ctr_group_desc, crcx_rate_ctr_index);
		if (!ratectr->mgcp_crcx_ctr_group)
			return -EINVAL;
		talloc_set_destructor(ratectr->mgcp_crcx_ctr_group, free_rate_counter_group);
		crcx_rate_ctr_index++;
	}
	if (ratectr->mgcp_mdcx_ctr_group == NULL) {
		ratectr->mgcp_mdcx_ctr_group = rate_ctr_group_alloc(ctx, &mgcp_mdcx_ctr_group_desc, mdcx_rate_ctr_index);
		if (!ratectr->mgcp_mdcx_ctr_group)
			return -EINVAL;
		talloc_set_destructor(ratectr->mgcp_mdcx_ctr_group, free_rate_counter_group);
		mdcx_rate_ctr_index++;
	}
	if (ratectr->mgcp_dlcx_ctr_group == NULL) {
		ratectr->mgcp_dlcx_ctr_group = rate_ctr_group_alloc(ctx, &mgcp_dlcx_ctr_group_desc, dlcx_rate_ctr_index);
		if (!ratectr->mgcp_dlcx_ctr_group)
			return -EINVAL;
		talloc_set_destructor(ratectr->mgcp_dlcx_ctr_group, free_rate_counter_group);
		dlcx_rate_ctr_index++;
	}
	if (ratectr->all_rtp_conn_stats == NULL) {
		ratectr->all_rtp_conn_stats = rate_ctr_group_alloc(ctx, &all_rtp_conn_rate_ctr_group_desc,
								 all_rtp_conn_rate_ctr_index);
		if (!ratectr->all_rtp_conn_stats)
			return -EINVAL;
		talloc_set_destructor(ratectr->all_rtp_conn_stats, free_rate_counter_group);
		all_rtp_conn_rate_ctr_index++;
	}
	return 0;
}