/*
Copyright (c) 2010-2021 Roger Light <roger@atchoo.org>

All rights reserved. This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
and Eclipse Distribution License v1.0 which accompany this distribution.

The Eclipse Public License is available at
   https://www.eclipse.org/legal/epl-2.0/
and the Eclipse Distribution License is available at
  http://www.eclipse.org/org/documents/edl-v10.php.

SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause

Contributors:
   Roger Light - initial implementation and documentation.
*/

#include "config.h"

#include <stdint.h>
#include <string.h>

#include "mosquitto/mqtt_protocol.h"
#include "net_mosq.h"
#include "packet_mosq.h"
#include "property_mosq.h"
#include "property_common.h"
#include "send_mosq.h"


int mosquitto_unsubscribe(struct mosquitto *mosq, int *mid, const char *sub)
{
	return mosquitto_unsubscribe_multiple(mosq, mid, 1, (char *const *const)&sub, NULL);
}


int mosquitto_unsubscribe_v5(struct mosquitto *mosq, int *mid, const char *sub, const mosquitto_property *properties)
{
	return mosquitto_unsubscribe_multiple(mosq, mid, 1, (char *const *const)&sub, properties);
}


int mosquitto_unsubscribe_multiple(struct mosquitto *mosq, int *mid, int sub_count, char *const *const sub, const mosquitto_property *properties)
{
	const mosquitto_property *outgoing_properties = NULL;
	mosquitto_property local_property;
	int rc;
	int i;
	uint32_t remaining_length = 0;
	int slen;

	if(!mosq){
		return MOSQ_ERR_INVAL;
	}
	if(mosq->protocol != mosq_p_mqtt5 && properties){
		return MOSQ_ERR_NOT_SUPPORTED;
	}
	if(!net__is_connected(mosq)){
		return MOSQ_ERR_NO_CONN;
	}

	if(properties){
		if(properties->client_generated){
			outgoing_properties = properties;
		}else{
			memcpy(&local_property, properties, sizeof(mosquitto_property));
			local_property.client_generated = true;
			local_property.next = NULL;
			outgoing_properties = &local_property;
		}
		rc = mosquitto_property_check_all(CMD_UNSUBSCRIBE, outgoing_properties);
		if(rc){
			return rc;
		}
	}

	for(i=0; i<sub_count; i++){
		if(mosquitto_sub_topic_check(sub[i])){
			return MOSQ_ERR_INVAL;
		}
		slen = (int)strlen(sub[i]);
		if(slen == 0){
			return MOSQ_ERR_INVAL;
		}
		if(mosquitto_validate_utf8(sub[i], slen)){
			return MOSQ_ERR_MALFORMED_UTF8;
		}
		remaining_length += 2U + (uint32_t)slen;
	}

	if(mosq->maximum_packet_size > 0){
		remaining_length += 2U + mosquitto_property_get_length_all(outgoing_properties);
		if(packet__check_oversize(mosq, remaining_length)){
			return MOSQ_ERR_OVERSIZE_PACKET;
		}
	}

	return send__unsubscribe(mosq, mid, sub_count, sub, outgoing_properties);
}
