/*************************************************************************
* (C) 2011 AITNET ltd - Sofia/Bulgaria - <misho@aitbg.com>
*  by Michael Pounov <misho@openbsd-bg.org>
*
* $Author: misho $
* $Id: pubmqtt.c,v 1.5 2017/10/08 22:49:25 misho Exp $
*
**************************************************************************
The ELWIX and AITNET software is distributed under the following
terms:

All of the documentation and software included in the ELWIX and AITNET
Releases is copyrighted by ELWIX - Sofia/Bulgaria <info@elwix.org>

Copyright 2004 - 2017
	by Michael Pounov <misho@elwix.org>.  All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. 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.
3. All advertising materials mentioning features or use of this software
   must display the following acknowledgement:
This product includes software developed by Michael Pounov <misho@elwix.org>
ELWIX - Embedded LightWeight unIX and its contributors.
4. Neither the name of AITNET nor the names of its contributors
   may be used to endorse or promote products derived from this software
   without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY AITNET AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
*/
#include "global.h"


extern const char sql_schema[];


/*
 * mqtt_db_log() Log database connection message
 *
 * @fmt = format string
 * @... = argument list
 * return: none
 */
static void
mqtt_rtlm_log(const char *fmt, ...)
{
	va_list lst;

	va_start(lst, fmt);
	vsyslog(LOG_ERR, fmt, lst);
	va_end(lst);
}
#define MQTT_RTLM_LOG(_sql)	(assert((_sql)), mqtt_rtlm_log("Error:: %s(%d) SQL #%d - %s", \
					__func__, __LINE__, \
					sqlite3_errcode((_sql)), sqlite3_errmsg((_sql))))

/* library pre-loaded actions */
void
_init()
{
	sqlite3_initialize();
}

void
_fini()
{
	sqlite3_shutdown();
}


/*
 * mqtt_rtlm_open() Open database connection
 *
 * @cfg = config filename
 * return: NULL error or SQL handle
 */
sqlite3 *
mqtt_rtlm_open(cfg_root_t *cfg)
{
	sqlite3 *sql = NULL;
	const char *str = NULL;

	if (!cfg)
		return NULL;

	str = cfg_getAttribute(cfg, "mqtt_pub", "name");
	if (!str) {
		mqtt_rtlm_log("Error:: Unknown database name ...\n");
		return NULL;
	}

	if (sqlite3_open_v2(str, &sql, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, NULL)) {
		MQTT_RTLM_LOG(sql);
		sqlite3_close(sql);
		return NULL;
	}

	if (sqlite3_exec(sql, sql_schema, NULL, NULL, NULL)) {
		MQTT_RTLM_LOG(sql);
		sqlite3_close(sql);
		return NULL;
	}
	return sql;
}

/*
 * mqtt_rtlm_close() Close database connection
 *
 * @sql = SQL handle
 * return: none
 */
void
mqtt_rtlm_close(sqlite3 *sql)
{
	sqlite3_close(sql);
}

/*
 * mqtt_rtlm_init_session() Create session
 *
 * @cfg = loaded config
 * @sql = SQL handle
 * @connid = connection id
 * @user = username
 * @host = hostname
 * @will = will flag if !=0 must fill arguments
 * @... = will arguments in order topic,msg,qos,retain
 * return: -1 error, 0 session already appears or >0 row changed
 */
int
mqtt_rtlm_init_session(cfg_root_t *cfg, sqlite3 *sql, const char *connid, const char *user, 
		const char *host, int will, ...)
{
	va_list lst;
	int ret = 0;
	char *str, *psStmt;
	sqlite3_stmt *stmt;

	if (!cfg || !sql)
		return -1;

	str = (char*) cfg_getAttribute(cfg, "mqtt_pub", "tbl_online");
	if (!str) {
		mqtt_rtlm_log("Error:: not found online table name");
		return -1;
	}
	if (!will)
		psStmt = sqlite3_mprintf("INSERT INTO %s (ConnID, Username, RemoteHost, "
				"WillFlag) VALUES ('%q', '%q', '%q', 0);", str, connid, user, host);
	else {
		va_start(lst, will);
		psStmt = sqlite3_mprintf("INSERT INTO %s (ConnID, Username, RemoteHost, "
				"WillFlag, WillRetain, WillQoS, WillMsg, WillTopic) "
				"VALUES ('%q', '%q', '%q', %d, %d, %d, '%q', '%q');", 
				str, connid, user, host, will, 
				va_arg(lst, int), va_arg(lst, int), va_arg(lst, char*), va_arg(lst, char*));
		va_end(lst);
	}

	if (sqlite3_prepare_v2(sql, psStmt, strlen(psStmt), &stmt, NULL)) {
		MQTT_RTLM_LOG(sql);
		sqlite3_free(psStmt);
		return -1;
	} else
		sqlite3_free(psStmt);
	if ((ret = sqlite3_step(stmt)) == SQLITE_DONE)
		ret = sqlite3_changes(sql);
	else {
		if (ret > SQLITE_OK && ret < SQLITE_ROW)
			MQTT_RTLM_LOG(sql);
		ret = 0;
	}
	sqlite3_finalize(stmt);

	return ret;
}

/*
 * mqtt_rtlm_fini_session() Delete session(s)
 *
 * @cfg = loaded config
 * @sql = SQL handle
 * @connid = connection id
 * @user = username
 * @host = hostname
 * return: -1 error, 0 session already appears or >0 row changed
 */
int
mqtt_rtlm_fini_session(cfg_root_t *cfg, sqlite3 *sql, const char *connid, const char *user, const char *host)
{
	int ret = 0;
	char *str, *psStmt;
	sqlite3_stmt *stmt;

	if (!cfg || !sql)
		return -1;

	str = (char*) cfg_getAttribute(cfg, "mqtt_pub", "tbl_online");
	if (!str) {
		mqtt_rtlm_log("Error:: not found online table name");
		return -1;
	}
	psStmt = sqlite3_mprintf("DELETE FROM %s WHERE ConnID = '%q' AND Username = '%q' "
			"AND RemoteHost LIKE '%q';", str, connid, user, host);

	if (sqlite3_prepare_v2(sql, psStmt, strlen(psStmt), &stmt, NULL)) {
		MQTT_RTLM_LOG(sql);
		sqlite3_free(psStmt);
		return -1;
	} else
		sqlite3_free(psStmt);
	if ((ret = sqlite3_step(stmt)) == SQLITE_DONE)
		ret = sqlite3_changes(sql);
	else {
		if (ret > SQLITE_OK && ret < SQLITE_ROW)
			MQTT_RTLM_LOG(sql);
		ret = 0;
	}
	sqlite3_finalize(stmt);

	return ret;
}

/*
 * mqtt_rtlm_chk_session() Check session(s)
 *
 * @cfg = loaded config
 * @sql = SQL handle
 * @connid = connection id
 * @user = username
 * @host = hostname
 * return: -1 error, 0 not logged or >0 logged found rows
 */
int
mqtt_rtlm_chk_session(cfg_root_t *cfg, sqlite3 *sql, const char *connid, const char *user, const char *host)
{
	int ret = 0;
	char *str, *psStmt;
	sqlite3_stmt *stmt;

	if (!cfg || !sql)
		return -1;

	str = (char*) cfg_getAttribute(cfg, "mqtt_pub", "tbl_online");
	if (!str) {
		mqtt_rtlm_log("Error:: not found online table name");
		return -1;
	}
	psStmt = sqlite3_mprintf("SELECT ConnID, RemoteHost FROM %s WHERE "
			"ConnID = '%q' AND Username LIKE '%q' AND RemoteHost LIKE '%q';", 
			str, connid, user, host);

	if (sqlite3_prepare_v2(sql, psStmt, strlen(psStmt), &stmt, NULL)) {
		MQTT_RTLM_LOG(sql);
		sqlite3_free(psStmt);
		return -1;
	} else
		sqlite3_free(psStmt);
	if (sqlite3_step(stmt) == SQLITE_ROW)
		ret = sqlite3_changes(sql);
	else
		ret = 0;
	sqlite3_finalize(stmt);

	return ret;
}

/*
 * mqtt_rtlm_write_topic() Publish topic
 *
 * @cfg = loaded config
 * @sql = SQL handle
 * @connid = connection id
 * @msgid = MessageID
 * @topic = topic
 * @txt = text
 * @txtlen = text length
 * @user = username
 * @host = hostname
 * @qos = QoS
 * @retain = !=0 retain message to database
 * return: -1 error, 0 no publish or >0 published ok
 */
int
mqtt_rtlm_write_topic(cfg_root_t *cfg, sqlite3 *sql, const char *connid, u_short msgid, 
		const char *topic, void *txt, int txtlen, const char *user, 
		const char *host, char qos, char retain)
{
	int ret = 0;
	char *str, *psStmt;
	sqlite3_stmt *stmt;

	if (!cfg || !sql || !topic)
		return -1;

	str = (char*) cfg_getAttribute(cfg, "mqtt_pub", "tbl_topics");
	if (!str) {
		mqtt_rtlm_log("Error:: not found topics table name");
		return -1;
	}
	psStmt = sqlite3_mprintf("INSERT INTO %s (QoS, Retain, ConnID, MsgID, Topic, Value, PubUser, "
			"PubDate, PubHost) VALUES (%d, %d, '%q', %u, '%q', ?1, '%q', "
			"datetime('now', 'localtime'), '%q');", 
			str, qos, retain, connid, msgid, topic, user, host);

	if (sqlite3_prepare_v2(sql, psStmt, strlen(psStmt), &stmt, NULL) || !stmt) {
		MQTT_RTLM_LOG(sql);
		sqlite3_free(psStmt);
		return -1;
	} else
		sqlite3_free(psStmt);
	if (sqlite3_bind_blob(stmt, 1, txt, txtlen, SQLITE_TRANSIENT)) {
		MQTT_RTLM_LOG(sql);
		sqlite3_finalize(stmt);
		return -1;
	}
	if ((ret = sqlite3_step(stmt)) == SQLITE_DONE)
		ret = sqlite3_changes(sql);
	else {
		if (ret > SQLITE_OK && ret < SQLITE_ROW)
			MQTT_RTLM_LOG(sql);
		ret = 0;
	}
	sqlite3_finalize(stmt);

	return ret;
}

/*
 * mqtt_rtlm_wipe_topic() Wipe all topics
 *
 * @cfg = loaded config
 * @sql = SQL handle
 * @connid = connection id
 * @user = username
 * @retain = -1 no matter
 * return: -1 error, 0 no changes or >0 deleted rows
 */
int
mqtt_rtlm_wipe_topic(cfg_root_t *cfg, sqlite3 *sql, const char *connid, const char *user, char retain)
{
	int ret = 0;
	char *str, *rtn, *psStmt;
	sqlite3_stmt *stmt;

	if (!cfg || !sql || !connid)
		return -1;

	str = (char*) cfg_getAttribute(cfg, "mqtt_pub", "tbl_topics");
	if (!str) {
		mqtt_rtlm_log("Error:: not found topics table name");
		return -1;
	}
	switch (retain) {
		case -1:
			rtn = "";
			break;
		case 0:
			rtn = "AND Retain = 0";
			break;
		default:
			rtn = "AND Retain != 0";
			break;
	}
	psStmt = sqlite3_mprintf("DELETE FROM %s WHERE ConnID = '%q' AND "
			"PubUser LIKE '%q' %s;", str, connid, user, rtn);

	if (sqlite3_prepare_v2(sql, psStmt, strlen(psStmt), &stmt, NULL)) {
		MQTT_RTLM_LOG(sql);
		sqlite3_free(psStmt);
		return -1;
	} else
		sqlite3_free(psStmt);
	if ((ret = sqlite3_step(stmt)) == SQLITE_DONE)
		ret = sqlite3_changes(sql);
	else {
		if (ret > SQLITE_OK && ret < SQLITE_ROW)
			MQTT_RTLM_LOG(sql);
		ret = 0;
	}
	sqlite3_finalize(stmt);

	return ret;
}

/*
 * mqtt_rtlm_delete_topic() Delete topic
 *
 * @cfg = loaded config
 * @sql = SQL handle
 * @connid = connection id
 * @msgid = MessageID
 * @topic = topic
 * @user = username
 * @host = hostname
 * @retain = -1 no matter
 * return: -1 error, 0 no changes or >0 deleted rows
 */
int
mqtt_rtlm_delete_topic(cfg_root_t *cfg, sqlite3 *sql, const char *connid, u_short msgid, 
		const char *topic, const char *user, const char *host, char retain)
{
	int ret = 0;
	char *str, *rtn, *psStmt;
	sqlite3_stmt *stmt;

	if (!cfg || !sql || !topic)
		return -1;

	str = (char*) cfg_getAttribute(cfg, "mqtt_pub", "tbl_topics");
	if (!str) {
		mqtt_rtlm_log("Error:: not found topics table name");
		return -1;
	}
	switch (retain) {
		case -1:
			rtn = "";
			break;
		case 0:
			rtn = "AND Retain = 0";
			break;
		default:
			rtn = "AND Retain != 0";
			break;
	}
	psStmt = sqlite3_mprintf("DELETE FROM %s WHERE ConnID = '%q' AND MsgID = %d AND "
			"Topic LIKE '%q' AND PubUser LIKE '%q' AND PubHost LIKE '%q' %s;", str, 
			connid, msgid, topic, user, host, rtn);

	if (sqlite3_prepare_v2(sql, psStmt, strlen(psStmt), &stmt, NULL)) {
		MQTT_RTLM_LOG(sql);
		sqlite3_free(psStmt);
		return -1;
	} else
		sqlite3_free(psStmt);
	if ((ret = sqlite3_step(stmt)) == SQLITE_DONE)
		ret = sqlite3_changes(sql);
	else {
		if (ret > SQLITE_OK && ret < SQLITE_ROW)
			MQTT_RTLM_LOG(sql);
		ret = 0;
	}
	sqlite3_finalize(stmt);

	return ret;
}

/*
 * mqtt_rtlm_read_topic() Get topic
 *
 * @cfg = loaded config
 * @sql = SQL handle
 * @connid = connection id
 * @topic = topic
 * @retain = retain 0 get only dynamic, >0 get only retained and -1 no matter
 * return: NULL error or not found and !=NULL allocated subscribe topics
 */
mqtt_subscr_t *
mqtt_rtlm_read_topic(cfg_root_t *cfg, sqlite3 *sql, const char *connid, 
		const char *topic, char retain)
{
	int rowz = 0;
	char *str, szStr[STRSIZ], *psStmt;
	sqlite3_stmt *stmt;
	register int j;
	mqtt_subscr_t *s = NULL;
	ait_val_t v;

	if (!cfg || !sql || !topic)
		return NULL;

	switch (retain) {
		case -1:
			memset(szStr, 0, sizeof szStr);
			break;
		case 0:
			snprintf(szStr, sizeof szStr, "AND Retain = 0");
			break;
		default:
			snprintf(szStr, sizeof szStr, "AND Retain > 0");
			break;
	}

	str = (char*) cfg_getAttribute(cfg, "mqtt_pub", "tbl_topics");
	if (!str) {
		mqtt_rtlm_log("Error:: not found topics table name");
		return NULL;
	}
	psStmt = sqlite3_mprintf("SELECT QoS, Topic, Value  FROM %s WHERE "
			"ConnID LIKE '%q' AND Topic LIKE '%q' %s;", 
			str, connid, topic, szStr);

	if (sqlite3_prepare_v2(sql, psStmt, strlen(psStmt), &stmt, NULL)) {
		MQTT_RTLM_LOG(sql);
		sqlite3_free(psStmt);
		return NULL;
	} else
		sqlite3_free(psStmt);

	/* calculate count of rows and allocate subscribe items */
	while (sqlite3_step(stmt) == SQLITE_ROW)
		rowz++;
	if (!(s = malloc((rowz + 1) * sizeof(mqtt_subscr_t)))) {
		mqtt_rtlm_log("Error:: System #%d - %s", errno, strerror(errno));
		goto end;
	} else
		memset(s, 0, (rowz + 1) * sizeof(mqtt_subscr_t));
	sqlite3_reset(stmt);

	/* fill with data */
	for (j = 0; j < rowz && sqlite3_step(stmt) == SQLITE_ROW; j++) {
		s[j].sub_ret = (char) sqlite3_column_int(stmt, 0);
		s[j].sub_topic.msg_base = (u_char*) strdup((char*) sqlite3_column_text(stmt, 1));
		s[j].sub_topic.msg_len = strlen((char*) s[j].sub_topic.msg_base);
		AIT_SET_PTR(&v, (void*) sqlite3_column_blob(stmt, 2), sqlite3_column_bytes(stmt, 2));
		s[j].sub_value.msg_len = AIT_LEN(&v);
		s[j].sub_value.msg_base = (u_char*) malloc(s[j].sub_value.msg_len);
		if (s[j].sub_value.msg_base)
			memcpy(s[j].sub_value.msg_base, AIT_GET_PTR(&v), s[j].sub_value.msg_len);
		AIT_FREE_VAL(&v);
	}
end:
	sqlite3_finalize(stmt);

	return s;
}

/*
 * mqtt_rtlm_write_subscribe() Subscribe topic
 *
 * @cfg = loaded config
 * @sql = SQL handle
 * @connid = connection id
 * @msgid = MessageID
 * @topic = topic
 * @user = username
 * @host = hostname
 * @qos = Subscribe QoS
 * return: -1 error, 0 no publish or >0 published ok
 */
int
mqtt_rtlm_write_subscribe(cfg_root_t *cfg, sqlite3 *sql, const char *connid, u_short msgid, 
		const char *topic, const char *user, const char *host, char qos)
{
	int ret = 0;
	char *str, *psStmt;
	sqlite3_stmt *stmt;

	if (!cfg || !sql || !topic)
		return -1;

	str = (char*) cfg_getAttribute(cfg, "mqtt_pub", "tbl_subscribes");
	if (!str) {
		mqtt_rtlm_log("Error:: not found subscribes table name");
		return -1;
	}
	psStmt = sqlite3_mprintf("INSERT INTO %s (ConnID, MsgID, QoS, Topic, PubUser, "
			"PubDate, PubHost) VALUES ('%q', %d, %d, '%q', '%q', "
			"datetime('now', 'localtime'), '%q');", str, 
			connid, msgid, qos, topic, user, host);

	if (sqlite3_prepare_v2(sql, psStmt, strlen(psStmt), &stmt, NULL)) {
		MQTT_RTLM_LOG(sql);
		sqlite3_free(psStmt);
		return -1;
	} else
		sqlite3_free(psStmt);
	if ((ret = sqlite3_step(stmt)) == SQLITE_DONE)
		ret = sqlite3_changes(sql);
	else {
		if (ret > SQLITE_OK && ret < SQLITE_ROW)
			MQTT_RTLM_LOG(sql);
		ret = 0;
	}
	sqlite3_finalize(stmt);

	return ret;
}

/*
 * mqtt_rtlm_delete_subscribe() Delete subscribe
 *
 * @cfg = loaded config
 * @sql = SQL handle
 * @connid = connection id
 * @topic = topic
 * @user = username
 * @host = hostname
 * return: -1 error, 0 no changes or >0 deleted rows
 */
int
mqtt_rtlm_delete_subscribe(cfg_root_t *cfg, sqlite3 *sql, const char *connid, 
		const char *topic, const char *user, const char *host)
{
	int ret = 0;
	char *str, *psStmt;
	sqlite3_stmt *stmt;

	if (!cfg || !sql || !topic)
		return -1;

	str = (char*) cfg_getAttribute(cfg, "mqtt_pub", "tbl_subscribes");
	if (!str) {
		mqtt_rtlm_log("Error:: not found subscribes table name");
		return -1;
	}
	psStmt = sqlite3_mprintf("DELETE FROM %s WHERE ConnID = '%q' AND "
			"Topic LIKE '%q' AND PubUser LIKE '%q' AND PubHost LIKE '%q';", str, 
			connid, topic, user, host);

	if (sqlite3_prepare_v2(sql, psStmt, strlen(psStmt), &stmt, NULL)) {
		MQTT_RTLM_LOG(sql);
		sqlite3_free(psStmt);
		return -1;
	} else
		sqlite3_free(psStmt);
	if ((ret = sqlite3_step(stmt)) == SQLITE_DONE)
		ret = sqlite3_changes(sql);
	else {
		if (ret > SQLITE_OK && ret < SQLITE_ROW)
			MQTT_RTLM_LOG(sql);
		ret = 0;
	}
	sqlite3_finalize(stmt);

	return ret;
}

/*
 * mqtt_rtlm_read_subscribe() Get subscribe topic
 *
 * @cfg = loaded config
 * @sql = SQL handle
 * @connid = connection id
 * @topic = topic
 * return: NULL error or not found and !=NULL allocated subscribe topics
 */
mqtt_subscr_t *
mqtt_rtlm_read_subscribe(cfg_root_t *cfg, sqlite3 *sql, const char *connid, const char *topic)
{
	int rowz = 0;
	char *str, *psStmt;
	sqlite3_stmt *stmt;
	register int j;
	mqtt_subscr_t *s = NULL;

	if (!cfg || !sql || !topic)
		return NULL;

	str = (char*) cfg_getAttribute(cfg, "mqtt_pub", "tbl_subscribes");
	if (!str) {
		mqtt_rtlm_log("Error:: not found subscribes table name");
		return NULL;
	}
	psStmt = sqlite3_mprintf("SELECT QoS, Topic FROM %s WHERE ConnID = '%q' AND "
			"Topic LIKE '%q';", str, connid, topic);

	if (sqlite3_prepare_v2(sql, psStmt, strlen(psStmt), &stmt, NULL)) {
		MQTT_RTLM_LOG(sql);
		sqlite3_free(psStmt);
		return NULL;
	} else
		sqlite3_free(psStmt);

	/* calculate count of rows and allocate subscribe items */
	while (sqlite3_step(stmt) == SQLITE_ROW)
		rowz++;
	if (!(s = malloc((rowz + 1) * sizeof(mqtt_subscr_t)))) {
		mqtt_rtlm_log("Error:: System #%d - %s", errno, strerror(errno));
		goto end;
	} else
		memset(s, 0, (rowz + 1) * sizeof(mqtt_subscr_t));
	sqlite3_reset(stmt);

	/* fill with data */
	for (j = 0; j < rowz && sqlite3_step(stmt) == SQLITE_ROW; j++) {
		s[j].sub_ret = (char) sqlite3_column_int(stmt, 0);
		s[j].sub_topic.msg_base = (u_char*) strdup((char*) sqlite3_column_text(stmt, 1));
		s[j].sub_topic.msg_len = strlen((char*) s[j].sub_topic.msg_base);
		s[j].sub_value.msg_base = NULL;
		s[j].sub_value.msg_len = 0;
	}
end:
	sqlite3_finalize(stmt);

	return s;
}