/*
Copyright (c) 2009-2015 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 v1.0
and Eclipse Distribution License v1.0 which accompany this distribution.
 
The Eclipse Public License is available at
   http://www.eclipse.org/legal/epl-v10.html
and the Eclipse Distribution License is available at
  http://www.eclipse.org/org/documents/edl-v10.php.
 
Contributors:
   Roger Light - initial implementation and documentation.
*/

#include <assert.h>
#include <stdio.h>
#include <string.h>

#include "config.h"

#include "mosquitto_broker.h"
#include "mqtt3_protocol.h"
#include "memory_mosq.h"
#include "packet_mosq.h"
#include "read_handle.h"
#include "send_mosq.h"
#include "sys_tree.h"
#include "util_mosq.h"

int mqtt3_packet_handle(struct mosquitto_db *db, struct mosquitto *context)
{
	if(!context) return MOSQ_ERR_INVAL;

	switch((context->in_packet.command)&0xF0){
		case PINGREQ:
			return handle__pingreq(context);
		case PINGRESP:
			return handle__pingresp(context);
		case PUBACK:
			return handle__pubackcomp(db, context, "PUBACK");
		case PUBCOMP:
			return handle__pubackcomp(db, context, "PUBCOMP");
		case PUBLISH:
			return handle__publish(db, context);
		case PUBREC:
			return handle__pubrec(context);
		case PUBREL:
			return handle__pubrel(db, context);
		case CONNECT:
			return handle__connect(db, context);
		case DISCONNECT:
			return handle__disconnect(db, context);
		case SUBSCRIBE:
			return handle__subscribe(db, context);
		case UNSUBSCRIBE:
			return handle__unsubscribe(db, context);
#ifdef WITH_BRIDGE
		case CONNACK:
			return handle__connack(db, context);
		case SUBACK:
			return handle__suback(context);
		case UNSUBACK:
			return handle__unsuback(context);
#endif
		default:
			/* If we don't recognise the command, return an error straight away. */
			return MOSQ_ERR_PROTOCOL;
	}
}

int handle__publish(struct mosquitto_db *db, struct mosquitto *context)
{
	char *topic;
	void *payload = NULL;
	uint32_t payloadlen;
	uint8_t dup, qos, retain;
	uint16_t mid = 0;
	int rc = 0;
	uint8_t header = context->in_packet.command;
	int res = 0;
	struct mosquitto_msg_store *stored = NULL;
	int len;
	char *topic_mount;
#ifdef WITH_BRIDGE
	char *topic_temp;
	int i;
	struct mosquitto__bridge_topic *cur_topic;
	bool match;
#endif

	dup = (header & 0x08)>>3;
	qos = (header & 0x06)>>1;
	if(qos == 3){
		log__printf(NULL, MOSQ_LOG_INFO,
				"Invalid QoS in PUBLISH from %s, disconnecting.", context->id);
		return 1;
	}
	retain = (header & 0x01);

	if(packet__read_string(&context->in_packet, &topic)) return 1;
	if(strlen(topic) == 0){
		/* Invalid publish topic, disconnect client. */
		mosquitto__free(topic);
		return 1;
	}
#ifdef WITH_BRIDGE
	if(context->bridge && context->bridge->topics && context->bridge->topic_remapping){
		for(i=0; i<context->bridge->topic_count; i++){
			cur_topic = &context->bridge->topics[i];
			if((cur_topic->direction == bd_both || cur_topic->direction == bd_in) 
					&& (cur_topic->remote_prefix || cur_topic->local_prefix)){

				/* Topic mapping required on this topic if the message matches */

				rc = mosquitto_topic_matches_sub(cur_topic->remote_topic, topic, &match);
				if(rc){
					mosquitto__free(topic);
					return rc;
				}
				if(match){
					if(cur_topic->remote_prefix){
						/* This prefix needs removing. */
						if(!strncmp(cur_topic->remote_prefix, topic, strlen(cur_topic->remote_prefix))){
							topic_temp = mosquitto__strdup(topic+strlen(cur_topic->remote_prefix));
							if(!topic_temp){
								mosquitto__free(topic);
								return MOSQ_ERR_NOMEM;
							}
							mosquitto__free(topic);
							topic = topic_temp;
						}
					}

					if(cur_topic->local_prefix){
						/* This prefix needs adding. */
						len = strlen(topic) + strlen(cur_topic->local_prefix)+1;
						topic_temp = mosquitto__malloc(len+1);
						if(!topic_temp){
							mosquitto__free(topic);
							return MOSQ_ERR_NOMEM;
						}
						snprintf(topic_temp, len, "%s%s", cur_topic->local_prefix, topic);
						topic_temp[len] = '\0';

						mosquitto__free(topic);
						topic = topic_temp;
					}
					break;
				}
			}
		}
	}
#endif
	if(mosquitto_pub_topic_check(topic) != MOSQ_ERR_SUCCESS){
		/* Invalid publish topic, just swallow it. */
		mosquitto__free(topic);
		return 1;
	}

	if(qos > 0){
		if(packet__read_uint16(&context->in_packet, &mid)){
			mosquitto__free(topic);
			return 1;
		}
	}

	payloadlen = context->in_packet.remaining_length - context->in_packet.pos;
	G_PUB_BYTES_RECEIVED_INC(payloadlen);
	if(context->listener && context->listener->mount_point){
		len = strlen(context->listener->mount_point) + strlen(topic) + 1;
		topic_mount = mosquitto__malloc(len+1);
		if(!topic_mount){
			mosquitto__free(topic);
			return MOSQ_ERR_NOMEM;
		}
		snprintf(topic_mount, len, "%s%s", context->listener->mount_point, topic);
		topic_mount[len] = '\0';

		mosquitto__free(topic);
		topic = topic_mount;
	}

	if(payloadlen){
		if(db->config->message_size_limit && payloadlen > db->config->message_size_limit){
			log__printf(NULL, MOSQ_LOG_DEBUG, "Dropped too large PUBLISH from %s (d%d, q%d, r%d, m%d, '%s', ... (%ld bytes))", context->id, dup, qos, retain, mid, topic, (long)payloadlen);
			goto process_bad_message;
		}
		payload = mosquitto__calloc(payloadlen+1, 1);
		if(!payload){
			mosquitto__free(topic);
			return 1;
		}
		if(packet__read_bytes(&context->in_packet, payload, payloadlen)){
			mosquitto__free(topic);
			mosquitto__free(payload);
			return 1;
		}
	}

	/* Check for topic access */
	rc = mosquitto_acl_check(db, context, topic, MOSQ_ACL_WRITE);
	if(rc == MOSQ_ERR_ACL_DENIED){
		log__printf(NULL, MOSQ_LOG_DEBUG, "Denied PUBLISH from %s (d%d, q%d, r%d, m%d, '%s', ... (%ld bytes))", context->id, dup, qos, retain, mid, topic, (long)payloadlen);
		goto process_bad_message;
	}else if(rc != MOSQ_ERR_SUCCESS){
		mosquitto__free(topic);
		if(payload) mosquitto__free(payload);
		return rc;
	}

	log__printf(NULL, MOSQ_LOG_DEBUG, "Received PUBLISH from %s (d%d, q%d, r%d, m%d, '%s', ... (%ld bytes))", context->id, dup, qos, retain, mid, topic, (long)payloadlen);
	if(qos > 0){
		db__message_store_find(context, mid, &stored);
	}
	if(!stored){
		dup = 0;
		if(db__message_store(db, context->id, mid, topic, qos, payloadlen, payload, retain, &stored, 0)){
			mosquitto__free(topic);
			if(payload) mosquitto__free(payload);
			return 1;
		}
	}else{
		dup = 1;
	}
	switch(qos){
		case 0:
			if(mqtt3_db_messages_queue(db, context->id, topic, qos, retain, &stored)) rc = 1;
			break;
		case 1:
			if(mqtt3_db_messages_queue(db, context->id, topic, qos, retain, &stored)) rc = 1;
			if(send__puback(context, mid)) rc = 1;
			break;
		case 2:
			if(!dup){
				res = db__message_insert(db, context, mid, mosq_md_in, qos, retain, stored);
			}else{
				res = 0;
			}
			/* db__message_insert() returns 2 to indicate dropped message
			 * due to queue. This isn't an error so don't disconnect them. */
			if(!res){
				if(send__pubrec(context, mid)) rc = 1;
			}else if(res == 1){
				rc = 1;
			}
			break;
	}
	mosquitto__free(topic);
	if(payload) mosquitto__free(payload);

	return rc;
process_bad_message:
	mosquitto__free(topic);
	if(payload) mosquitto__free(payload);
	switch(qos){
		case 0:
			return MOSQ_ERR_SUCCESS;
		case 1:
			return send__puback(context, mid);
		case 2:
			db__message_store_find(context, mid, &stored);
			if(!stored){
				if(db__message_store(db, context->id, mid, NULL, qos, 0, NULL, false, &stored, 0)){
					return 1;
				}
				res = db__message_insert(db, context, mid, mosq_md_in, qos, false, stored);
			}else{
				res = 0;
			}
			if(!res){
				res = send__pubrec(context, mid);
			}
			return res;
	}
	return 1;
}