/********************************************************************************
 *      Copyright:  (C) 2021 LingYun IoT System Studio
 *                  All rights reserved.
 *
 *       Filename:  mqtt.h
 *    Description:  This head file is MQTT subscriber and publisher thread code
 *
 *        Version:  1.0.0(20/04/21)
 *         Author:  Guo Wenxue <guowenxue@gmail.com>
 *      ChangeLog:  1, Release initial version on "20/04/21 15:46:42"
 *
 ********************************************************************************/

#include <string.h>
#include <math.h>
#include <cjson/cJSON.h>
#include <mosquitto.h>
#include <errno.h>

#include "util_proc.h"
#include "logger.h"
#include "hal.h"
#include "conf.h"


/*+-------------------------------------------+
 *|                                           |
 *|    MQTT publisher thread worker code      |
 *|                                           |
 *+-------------------------------------------+*/


void pub_connect_callback(struct mosquitto *mosq, void *userdata, int result)
{
    iotd_ctx_t             *ctx = (iotd_ctx_t *)userdata;
    mqtt_ctx_t             *mqtt_ctx;
    hal_ctx_t              *hal_ctx;
    int                     rv = 0;
    char                    msg[128];
    float                   temp = 0.0; /* temperature */
    float                   rh = 0.0;   /* relative humidity */
    int                     retain = 0;

    mqtt_ctx = &ctx->mqtt_ctx;
    hal_ctx = &ctx->hal_ctx;


    if( result )
    {
        log_error("Publisher connect to broker server[%s:%d] failed, rv=%d\n", mqtt_ctx->host, mqtt_ctx->port, result);
        return ;
    }
    log_info("Publisher connect to broker server[%s:%d] successfully\n", mqtt_ctx->host, mqtt_ctx->port);


    if( hal_ctx->ds18b20_enable )
    {
        memset(msg, 0, sizeof(msg));

        if( ds18b20_get_temperature(&temp) < 0 )
            snprintf(msg, sizeof(msg), "{ \"id\":%s, \"temp\":\"error\" }", mqtt_ctx->id);
        else
            snprintf(msg, sizeof(msg), "{ \"id\":%s, \"temp\":\"%.2f\" }", mqtt_ctx->id, temp);

        rv = mosquitto_publish(mosq, NULL, mqtt_ctx->pubTopic, strlen(msg), msg, mqtt_ctx->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( hal_ctx->sht2x_enable )
    {
        memset(msg, 0, sizeof(msg));

        if( sht2x_get_temp_humidity(&temp, &rh) < 0 )
            snprintf(msg, sizeof(msg), "{ \"id\":%s, \"temp\":\"error\", \"RH\":\"error\" }", mqtt_ctx->id);
        else
            snprintf(msg, sizeof(msg), "{ \"id\":%s, \"temp\":\"%.2f\", \"RH\":\"%.2f\" }", mqtt_ctx->id, temp, rh);

        rv = mosquitto_publish(mosq, NULL, mqtt_ctx->pubTopic, strlen(msg), msg, mqtt_ctx->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);
        }
    }


    log_info("Publisher broadcast over and disconnect broker now\n", mqtt_ctx->host, mqtt_ctx->port);
    mosquitto_disconnect(mosq);

    return ;
}


void *mqtt_pub_worker(void *args)
{
    struct mosquitto       *mosq;
    bool                    session = true;

    iotd_ctx_t             *ctx = (iotd_ctx_t *)args;
    mqtt_ctx_t             *mqtt_ctx;

    if( !ctx )
    {
        log_error("Invalid input arguments\n");
        return NULL;
    }

    mqtt_ctx = &ctx->mqtt_ctx;


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

    /* set connnect to broker username and password  */
    if( strlen(mqtt_ctx->uid)> 0  && strlen(mqtt_ctx->pwd)> 0 )
        mosquitto_username_pw_set(mosq, mqtt_ctx->uid, mqtt_ctx->pwd);

    /* set callback functions */
    mosquitto_connect_callback_set(mosq, pub_connect_callback);

    while( !g_signal.stop )
    {
        /* connect to MQTT broker  */
        if( mosquitto_connect(mosq, mqtt_ctx->host, mqtt_ctx->port, mqtt_ctx->keepalive) )
        {
            log_error("Publisher connect to broker[%s:%d] failure: %s\n", mqtt_ctx->host, mqtt_ctx->port, strerror(errno));
            msleep(1000);
            continue;
        }

        /* -1: use default timeout 1000ms  1: unused */
        mosquitto_loop_forever(mosq, -1, 1);

        /* Publisher broadcast sensors data message interval time, unit seconds */
        sleep( mqtt_ctx->interval );
    }

    mosquitto_destroy(mosq);
    return NULL;
}

/*+-------------------------------------------+
 *|                                           |
 *|    MQTT Subscriber thread worker code     |
 *|                                           |
 *+-------------------------------------------+*/

void sub_connect_callback(struct mosquitto *mosq, void *userdata, int result)
{
    iotd_ctx_t             *ctx = (iotd_ctx_t *)userdata;

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

    log_info("Subscriber connect to broker server[%s:%d] successfully\n", ctx->mqtt_ctx.host, ctx->mqtt_ctx.port);

    log_info("Subscriber subTopic '%s' with Qos[%d]\n", ctx->mqtt_ctx.subTopic, ctx->mqtt_ctx.subQos);
    mosquitto_subscribe(mosq, NULL, ctx->mqtt_ctx.subTopic, ctx->mqtt_ctx.subQos);
}

void sub_disconnect_callback(struct mosquitto *mosq, void *userdata, int result)
{
    iotd_ctx_t             *ctx = (iotd_ctx_t *)userdata;

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

void proc_json_items(cJSON *root)
{
    int                    i;
    char                  *value;
    cJSON                 *item;

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

    for( i=0; i<cJSON_GetArraySize(root); i++ )
    {
        item = cJSON_GetArrayItem(root, i);
        if( !item )
            break;

        /* if item is cJSON_Object, then recursive call proc_json */
        if( cJSON_Object == item->type )
        {
            proc_json_items(item);
        }
        else if( cJSON_Array != item->type )
        {
            value = cJSON_Print(item);

            log_debug("JSON Parser key: %s value: %s\n", item->string, value);
            if( strstr(item->string, "light") || strstr(item->string, "led") || strstr(item->string, "relay"))
            {
                if( strstr(value, "on") || strstr(value, "off") )
                {
                    log_info("parser get turn '%s' %s from JSON string\n", item->string, value);
                    gpio_out(item->string, value);
                }
            }

            free(value); /* must free it, or it will result memory leak */
        }
    }
}

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

    cJSON                  *root = NULL;
    cJSON                  *item;
    char                   *value;


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

    log_debug("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 ;
    }

    /* check ID matched or not */
    item = cJSON_GetObjectItem(root, "id");
    if( !item )
    {
        log_error("cJSON_Parse get ID failure: %s\n", cJSON_GetErrorPtr());
        goto OUT;
    }

    value = cJSON_PrintUnformatted(item);
    if( strcasecmp(value, ctx->mqtt_ctx.id) )
    {
        log_warn("cJSON_Parse get ID not matchs [%s<->%s], drop this message!\n", value, ctx->mqtt_ctx.id);
        free(value);
        goto OUT;
    }

    free(value);

    /* proc JSON mesage */
    proc_json_items(root);

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


void *mqtt_sub_worker(void *args)
{
    struct mosquitto       *mosq;
    bool                    session = true;

    iotd_ctx_t             *ctx = (iotd_ctx_t *)args;
    mqtt_ctx_t             *mqtt_ctx;

    if( !ctx )
    {
        log_error("Invalid input arguments\n");
        return NULL;
    }

    mqtt_ctx = &ctx->mqtt_ctx;


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

    /* set connnect to broker username and password  */
    if( strlen(mqtt_ctx->uid)> 0  && strlen(mqtt_ctx->pwd)> 0 )
        mosquitto_username_pw_set(mosq, mqtt_ctx->uid, mqtt_ctx->pwd);

    /* set callback functions */
    mosquitto_connect_callback_set(mosq, sub_connect_callback);
    mosquitto_disconnect_callback_set(mosq, sub_disconnect_callback);
    mosquitto_message_callback_set(mosq, sub_message_callback);

    while( !g_signal.stop )
    {
        /* connect to MQTT broker  */
        if( mosquitto_connect(mosq, mqtt_ctx->host, mqtt_ctx->port, mqtt_ctx->keepalive) )
        {
            log_error("Subscriber connect to broker[%s:%d] failure: %s\n", mqtt_ctx->host, mqtt_ctx->port, strerror(errno));
            msleep(1000);
            continue;
        }

        /* -1: use default timeout 1000ms  1: unused */
        mosquitto_loop_forever(mosq, -1, 1);
    }

    mosquitto_destroy(mosq);
    return NULL;
}