/*********************************************************************************
 *      Copyright:  (C) 2019 LingYun IoT System Studio
 *                  All rights reserved.
 *
 *       Filename:  main.c
 *    Description:  This file is MQTT publisher/subscriber example program.
 *
 *        Version:  1.0.0(29/01/19)
 *         Author:  Guo Wenxue <guowenxue@gmail.com>
 *      ChangeLog:  1, Release initial version on "29/01/19 15:34:41"
 *
 ********************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>
#include <getopt.h>
#include <libgen.h>
#include <string.h>
#include <errno.h>

#include <mosquitto.h>
#include <cjson/cJSON.h>

#include "logger.h"
#include "proc.h"
#include "config.h"
#include "ds18b20.h"
#include "sht20.h"
#include "leds.h"
#include "relay.h"

#define PROG_VERSION               "v1.0.0"
#define DAEMON_PIDFILE             "/tmp/.iotd.pid"

void *mqtt_worker(void *args);

static void program_usage(char *progname)
{
    printf("Usage: %s [OPTION]...\n", progname);
    printf(" %s is LingYun studio iotd program running on RaspberryPi\n", progname);

    printf("\nMandatory arguments to long options are mandatory for short options too:\n");
    printf(" -b[daemon  ]  Running in daemon mode\n");
    printf(" -d[debug   ]  Running in debug mode\n");
    printf(" -c[conf    ]  Specify configure file\n");
    printf(" -h[help    ]  Display this help information\n");
    printf(" -v[version ]  Display the program version\n");

    printf("\n%s version %s\n", progname, PROG_VERSION);
    return;
}

int main (int argc, char **argv)
{
    int                daemon = 0;
    pthread_t          tid;
    iotd_ctx_t         ctx;
    char               *conf_file="/etc/iotd.conf";
    int                debug = 0;
    int                opt;
    char              *progname=NULL;

    struct option long_options[] = {
        {"conf", required_argument, NULL, 'c'},
        {"daemon", no_argument, NULL, 'b'},
        {"debug", no_argument, NULL, 'd'},
        {"version", no_argument, NULL, 'v'},
        {"help", no_argument, NULL, 'h'},
        {NULL, 0, NULL, 0}
    };

    progname = (char *)basename(argv[0]);

    /* parser the command line parameters */
    while ((opt = getopt_long(argc, argv, "c:bdvh", long_options, NULL)) != -1)
    {
        switch (opt)
        {
            case 'c': /* Set configure file */
                conf_file = optarg;
                break;

            case 'b': /* Set daemon running */
                daemon = 1;
                break;

            case 'd': /* Set debug running */
                debug = 1;
                break;

            case 'v':  /* Get software version */
                printf("%s version %s\n", progname, PROG_VERSION);
                return 0;

            case 'h':  /* Get help information */
                program_usage(progname);
                return 0;

            default:
                break;
        }
    }

    /* parser configure file */
    if( parser_conf(conf_file, &ctx, debug)<0 )
    {
        fprintf(stderr, "Parser iotd configure file failure\n");
        return -2;
    }

    /* install signal proc handler */
    install_default_signal();

    /* check program already running or not, if already running then exit, or set running as daemon */
    if( check_set_program_running(daemon, DAEMON_PIDFILE) < 0 )
        goto cleanup;

    /* initial mosquitto library */
    mosquitto_lib_init();

    /* start MQTT thread */
    if( thread_start(&tid, mqtt_worker, &ctx.mqtt ) < 0 )
    {
        log_error("Start MQTT worker thread failure\n");
        goto cleanup;
    }
    log_info("Start MQTT worker thread ok\n");

    /* control thread loop */
    while( !g_signal.stop )
    {
        sleep(1);
    }

cleanup:
    mosquitto_lib_cleanup();
    log_close();

    return 0;
}


/*
 * +--------------------------------+
 * |      MQTT Thread worker        |
 * +--------------------------------+
 */

/* process publisher(uplink) data */
void pub_connect_callback(struct mosquitto *mosq, void *userdata, int result)
{
    mqtt_ctx_t             *mqtt = (mqtt_ctx_t *)userdata;
    iotd_ctx_t             *iotd = to_iotd(mqtt);
    int                     rv = 0;
    char                    msg[128];
    float                   temp = 0.0; /* temperature */
    float                   rh = 0.0;   /* relative humidity */
    int                     retain = 0;
    static time_t           last_time = 0;

    /* publish time is not arrive */
    if( !check_timeout(&last_time, mqtt->interval) )
        return ;

    log_debug("Publish topic '%s'\n", mqtt->pubTopic);

    if( iotd->hwinfo.ds18b20 )
    {
        log_debug("DS18B20 temperature sensor enabled, start broadcast it\n");
        if( ds18b20_get_temperature(&temp)<0 )
            return ;

        memset(msg, 0, sizeof(msg));
        snprintf(msg, sizeof(msg), "{\"temperature\":%.2f}", temp);
        rv = mosquitto_publish(mosq, NULL, mqtt->pubTopic, strlen(msg), msg, mqtt->pubQos, retain);
        if( rv )
        {
            log_error("Publisher broadcast message '%s' failure: %d\n", msg, rv);
        }
        else
        {
            log_info("Publisher broadcast message '%s' ok\n", msg);
        }
    }

    if( iotd->hwinfo.sht2x )
    {
        log_debug("SHT2X temperature and humidity sensor enabled, start broadcast it\n");
        if( sht2x_get_temp_humidity(&temp, &rh)<0 )
            return ;

        memset(msg, 0, sizeof(msg));
        snprintf(msg, sizeof(msg), "{\"temperature\":%.2f, \"humidity\":%.2f}", temp, rh);
        rv = mosquitto_publish(mosq, NULL, mqtt->pubTopic, strlen(msg), msg, mqtt->pubQos, retain);
        if( rv )
        {
            log_error("Publisher broadcast message '%s' failure: %d\n", msg, rv);
        }
        else
        {
            log_info("Publisher broadcast message '%s' ok\n", msg);
        }
    }

    return ;
}

/* process subscriber(downlink) data */
void proc_json_items(cJSON *root, mqtt_ctx_t *mqtt)
{
    iotd_ctx_t             *iotd = to_iotd(mqtt);
    cJSON                  *item;
    char                    leds[LED_CNT][16] = {"RedLed", "GreenLed", "BlueLed"};
    char                    relays[RELAY_CNT][16] = {"Relay"};
    int                     which;

    if( !root )
    {
        log_error("Invalid input arguments $root\n");
        return ;
    }

    /* parser JSON command for relays */
    if( iotd->hwinfo.relay )
    {
        for(which=0; which<RELAY_CNT; which++)
        {
            item = cJSON_GetObjectItem(root, relays[which]);
            if( !item )
                continue;

            if( strcasecmp(item->valuestring, "on") )
                turn_relay(which, ON);
            else if( strcasecmp(item->valuestring, "off") )
                turn_relay(which, OFF);
        }
    }

    /* parser JSON command for RGB leds */
    if( iotd->hwinfo.led )
    {
        for(which=0; which<LED_CNT; which++)
        {
            item = cJSON_GetObjectItem(root, leds[which]);
            if( !item )
                continue;

            if( strcasecmp(item->valuestring, "on") )
                turn_led(which, ON);
            else if( strcasecmp(item->valuestring, "off") )
                turn_led(which, OFF);
        }
    }

    return ;
}

void sub_message_callback(struct mosquitto *mosq, void *userdata, const struct mosquitto_message *message)
{
    mqtt_ctx_t             *ctx = (mqtt_ctx_t *)userdata;

    cJSON                  *root = NULL;

    if ( !message->payloadlen )
    {
        log_error("%s (null)\n", message->topic);
        return ;
    }

    log_info("Subscriber receive message: '%s'\n", message->payload);

    root = cJSON_Parse(message->payload);
    if( !root )
    {
        log_error("cJSON_Parse parser failure: %s\n", cJSON_GetErrorPtr());
        return ;
    }

    /* process receive message data */
    proc_json_items(root, ctx);

    /* must delete it, or it will result memory leak */
    cJSON_Delete(root);

    return ;
}

void mqtt_connect_callback(struct mosquitto *mosq, void *userdata, int result)
{
    mqtt_ctx_t             *ctx = (mqtt_ctx_t *)userdata;

    if( result )
    {
        log_error("mosquitto connect to broker server failed, rv=%d\n", result);
        return ;
    }

    log_info("mosquitto connect to broker server[%s:%d] successfully\n", ctx->host, ctx->port);
    mosquitto_subscribe(mosq, NULL, ctx->subTopic, ctx->subQos);
}

void mqtt_disconnect_callback(struct mosquitto *mosq, void *userdata, int result)
{
    mqtt_ctx_t             *ctx = (mqtt_ctx_t *)userdata;

    log_warn("mosquitto disconnect to broker server[%s:%d], reason=%d\n", ctx->host, ctx->port, result);
}

void *mqtt_worker(void *args)
{
    mqtt_ctx_t             *ctx = (mqtt_ctx_t *)args;
    struct mosquitto       *mosq;
    bool                    session = true;
    int                     rv = 0;

    mosq = mosquitto_new(ctx->devid, session, ctx);
    if( !mosq )
    {
        log_error("mosquitto_new failure\n");
        return NULL;
    }

    /* connnect to broker by token or uid/pwd */
    if( strlen(ctx->token ) > 0)
    {
        log_info("Using token authentication: '%s'\n", ctx->token);
        mosquitto_username_pw_set(mosq, ctx->token, NULL);
    }
    else if( strlen(ctx->uid)> 0  && strlen(ctx->pwd)> 0 )
    {
        log_info("Using username/password authentication\n");
        mosquitto_username_pw_set(mosq, ctx->uid, ctx->pwd);
    }

    /* set callback functions */
    mosquitto_connect_callback_set(mosq, mqtt_connect_callback);
    mosquitto_disconnect_callback_set(mosq, mqtt_disconnect_callback);
    mosquitto_message_callback_set(mosq, sub_message_callback);

    while( !g_signal.stop )
    {
        /* connect to MQTT broker  */
        if( mosquitto_connect(mosq, ctx->host, ctx->port, ctx->keepalive) )
        {
            log_error("mosquitto connect to broker[%s:%d] failure: %s\n", ctx->host, ctx->port, strerror(errno));
            sleep(1);
            continue;
        }

        while(!g_signal.stop)
        {
            /* periodically publish and report data */
            pub_connect_callback(mosq, ctx, MOSQ_ERR_SUCCESS);

            /* MQTT process in Non-blocking mode, timeout for 1s */
            if( MOSQ_ERR_SUCCESS != (rv = mosquitto_loop(mosq, 1000, 1)) )
            {
                log_warn("MQTT loop error: %s, reconnecting...\n", mosquitto_strerror(rv));
                break;
            }
        }

        mosquitto_disconnect(mosq);
        sleep(1);
    }

    mosquitto_destroy(mosq);
    return NULL;
}