/*
Copyright (c) 2009-2016 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 <stdarg.h>
#include <stdio.h>
#include <string.h>
#ifndef WIN32
#include <syslog.h>
#endif
#include <time.h>

#ifndef CMAKE
#include "config.h"
#endif

#include "mosquitto_broker_internal.h"
#include "memory_mosq.h"
#include "util_mosq.h"

extern struct mosquitto_db int_db;

#ifdef WIN32
HANDLE syslog_h;
#endif

/* Options for logging should be:
 *
 * A combination of:
 * Via syslog
 * To a file
 * To stdout/stderr
 * To topics
 */

/* Give option of logging timestamp.
 * Logging pid.
 */
static int log_destinations = MQTT3_LOG_STDERR;
static int log_priorities = MOSQ_LOG_ERR | MOSQ_LOG_WARNING | MOSQ_LOG_NOTICE | MOSQ_LOG_INFO;

int log__init(struct mosquitto__config *config)
{
	int rc = 0;

	log_priorities = config->log_type;
	log_destinations = config->log_dest;

	if(log_destinations & MQTT3_LOG_SYSLOG){
#ifndef WIN32
		openlog("mosquitto", LOG_PID|LOG_CONS, config->log_facility);
#else
		syslog_h = OpenEventLog(NULL, "mosquitto");
#endif
	}

	if(log_destinations & MQTT3_LOG_FILE){
		if(drop_privileges(config, true)){
			return 1;
		}
		config->log_fptr = mosquitto__fopen(config->log_file, "at");
		if(!config->log_fptr){
			log_destinations = MQTT3_LOG_STDERR;
			log_priorities = MOSQ_LOG_ERR;
			log__printf(NULL, MOSQ_LOG_ERR, "Error: Unable to open log file %s for writing.", config->log_file);
			return MOSQ_ERR_INVAL;
		}
		restore_privileges();
	}
	return rc;
}

int log__close(struct mosquitto__config *config)
{
	if(log_destinations & MQTT3_LOG_SYSLOG){
#ifndef WIN32
		closelog();
#else
		CloseEventLog(syslog_h);
#endif
	}
	if(log_destinations & MQTT3_LOG_FILE){
		if(config->log_fptr){
			fclose(config->log_fptr);
			config->log_fptr = NULL;
		}
	}

	/* FIXME - do something for all destinations! */
	return MOSQ_ERR_SUCCESS;
}

int log__vprintf(int priority, const char *fmt, va_list va)
{
	char *s;
	char *st;
	int len;
#ifdef WIN32
	char *sp;
#endif
	const char *topic;
	int syslog_priority;
	time_t now = time(NULL);
	static time_t last_flush = 0;

	if((log_priorities & priority) && log_destinations != MQTT3_LOG_NONE){
		switch(priority){
			case MOSQ_LOG_SUBSCRIBE:
				topic = "$SYS/broker/log/M/subscribe";
#ifndef WIN32
				syslog_priority = LOG_NOTICE;
#else
				syslog_priority = EVENTLOG_INFORMATION_TYPE;
#endif
				break;
			case MOSQ_LOG_UNSUBSCRIBE:
				topic = "$SYS/broker/log/M/unsubscribe";
#ifndef WIN32
				syslog_priority = LOG_NOTICE;
#else
				syslog_priority = EVENTLOG_INFORMATION_TYPE;
#endif
				break;
			case MOSQ_LOG_DEBUG:
				topic = "$SYS/broker/log/D";
#ifndef WIN32
				syslog_priority = LOG_DEBUG;
#else
				syslog_priority = EVENTLOG_INFORMATION_TYPE;
#endif
				break;
			case MOSQ_LOG_ERR:
				topic = "$SYS/broker/log/E";
#ifndef WIN32
				syslog_priority = LOG_ERR;
#else
				syslog_priority = EVENTLOG_ERROR_TYPE;
#endif
				break;
			case MOSQ_LOG_WARNING:
				topic = "$SYS/broker/log/W";
#ifndef WIN32
				syslog_priority = LOG_WARNING;
#else
				syslog_priority = EVENTLOG_WARNING_TYPE;
#endif
				break;
			case MOSQ_LOG_NOTICE:
				topic = "$SYS/broker/log/N";
#ifndef WIN32
				syslog_priority = LOG_NOTICE;
#else
				syslog_priority = EVENTLOG_INFORMATION_TYPE;
#endif
				break;
			case MOSQ_LOG_INFO:
				topic = "$SYS/broker/log/I";
#ifndef WIN32
				syslog_priority = LOG_INFO;
#else
				syslog_priority = EVENTLOG_INFORMATION_TYPE;
#endif
				break;
#ifdef WITH_WEBSOCKETS
			case MOSQ_LOG_WEBSOCKETS:
				topic = "$SYS/broker/log/WS";
#ifndef WIN32
				syslog_priority = LOG_DEBUG;
#else
				syslog_priority = EVENTLOG_INFORMATION_TYPE;
#endif
				break;
#endif
			default:
				topic = "$SYS/broker/log/E";
#ifndef WIN32
				syslog_priority = LOG_ERR;
#else
				syslog_priority = EVENTLOG_ERROR_TYPE;
#endif
		}
		len = strlen(fmt) + 500;
		s = mosquitto__malloc(len*sizeof(char));
		if(!s) return MOSQ_ERR_NOMEM;

		vsnprintf(s, len, fmt, va);
		s[len-1] = '\0'; /* Ensure string is null terminated. */

		if(log_destinations & MQTT3_LOG_STDOUT){
			if(int_db.config && int_db.config->log_timestamp){
				fprintf(stdout, "%d: %s\n", (int)now, s);
			}else{
				fprintf(stdout, "%s\n", s);
			}
			fflush(stdout);
		}
		if(log_destinations & MQTT3_LOG_STDERR){
			if(int_db.config && int_db.config->log_timestamp){
				fprintf(stderr, "%d: %s\n", (int)now, s);
			}else{
				fprintf(stderr, "%s\n", s);
			}
			fflush(stderr);
		}
		if(log_destinations & MQTT3_LOG_FILE && int_db.config->log_fptr){
			if(int_db.config && int_db.config->log_timestamp){
				fprintf(int_db.config->log_fptr, "%d: %s\n", (int)now, s);
			}else{
				fprintf(int_db.config->log_fptr, "%s\n", s);
			}
			if(now - last_flush > 1){
				fflush(int_db.config->log_fptr);
				last_flush = now;
			}
		}
		if(log_destinations & MQTT3_LOG_SYSLOG){
#ifndef WIN32
			syslog(syslog_priority, "%s", s);
#else
			sp = (char *)s;
			ReportEvent(syslog_h, syslog_priority, 0, 0, NULL, 1, 0, &sp, NULL);
#endif
		}
		if(log_destinations & MQTT3_LOG_TOPIC && priority != MOSQ_LOG_DEBUG){
			if(int_db.config && int_db.config->log_timestamp){
				len += 30;
				st = mosquitto__malloc(len*sizeof(char));
				if(!st){
					mosquitto__free(s);
					return MOSQ_ERR_NOMEM;
				}
				snprintf(st, len, "%d: %s", (int)now, s);
				db__messages_easy_queue(&int_db, NULL, topic, 2, strlen(st), st, 0);
				mosquitto__free(st);
			}else{
				db__messages_easy_queue(&int_db, NULL, topic, 2, strlen(s), s, 0);
			}
		}
		mosquitto__free(s);
	}

	return MOSQ_ERR_SUCCESS;
}

int log__printf(struct mosquitto *mosq, int priority, const char *fmt, ...)
{
	va_list va;
	int rc;

	va_start(va, fmt);
	rc = log__vprintf(priority, fmt, va);
	va_end(va);

	return rc;
}

int mosquitto_log_vprintf(int level, const char *fmt, va_list va)
{
	return log__vprintf(level, fmt, va);
}

void mosquitto_log_printf(int level, const char *fmt, ...)
{
	va_list va;

	va_start(va, fmt);
	log__vprintf(level, fmt, va);
	va_end(va);
}