/*********************************************************************************
 *      Copyright:  (C) 2019 LingYun IoT System Studio
 *                  All rights reserved.
 *
 *       Filename:  main.c
 *    Description:  This file 
 *                 
 *        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 <time.h>
#include <unistd.h>
#include <getopt.h>
#include <libgen.h>
#include <string.h>

#include <mosquitto.h>

#include "logger.h"
#include "cJSON.h"
#include "proc.h"

#include "conf.h"

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

int check_set_program_running(int daemon);
void *mqtt_sub_worker(void *args);

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

    printf("\nMandatory arguments to long options are mandatory for short options too:\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)
{
    float              temp;
    float              rh;
    int                daemon = 1;
    pthread_t          tid;
    mqtt_ctx_t         ctx;
    char               *conf_file=NULL;
    int                debug = 0;
    int                opt;
    char              *progname=NULL;

    struct option long_options[] = {
        {"conf", required_argument, NULL, 'c'},
        {"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:dvh", long_options, NULL)) != -1)
    {
        switch (opt)
        {
            case 'c': /* Set configure file */
                conf_file = optarg;
                break;

            case 'd': /* Set debug running */
                daemon = 0;
                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;
        }
    
    }

    if( !conf_file )
        debug = 1;

    if( mqttd_parser_conf(conf_file, &ctx, debug)<0 )
    {
        fprintf(stderr, "Parser mqtted configure file failure\n");
        return -2;
    }

    install_proc_signal();

    if( check_set_program_running(daemon) < 0 ) 
        goto OUT;

    if( !debug )

    mosquitto_lib_init();

    if( thread_start(&tid, mqtt_sub_worker, &ctx ) < 0 )
    {
        log_fatal("Start MQTT subsciber worker thread failure\n");
        goto OUT;
    }
    log_nrml("Start MQTT subsciber worker thread ok\n");

    while( ! g_signal.stop )
    {
        sleep(1);
        //log_nrml("Main control thread continue running\n");
    }


OUT:
    mosquitto_lib_cleanup();
    logger_term();
    
    return 0;
} /* ----- End of main() ----- */


int check_set_program_running(int daemon)
{
    if( check_daemon_running(DAEMON_PIDFILE) ) 
    {
        log_err("Program already running, process exit now");
        return -1;
    }

    if( daemon ) 
    {
        if( set_daemon_running(DAEMON_PIDFILE) < 0 )
        {
            log_err("set program running as daemon failure\n");
            return -2;
        }
    }
    else
    {
        if( record_daemon_pid(DAEMON_PIDFILE) < 0 )
        {
            log_err("record program running PID failure\n");
            return -3;
        }
    }

    return 0;
}


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

    if( result )
    {
        log_err("Subscriber connect to broker server failed, rv=%d\n", result);
        return ;
    }
    
    log_nrml("Subscriber connect to broker server[%s:%d] successfully\n", ctx->host, ctx->port); 
    mosquitto_subscribe(mosq, NULL, ctx->subTopic, ctx->subQos);
}

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

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


int turn_camera(char *status)
{
    FILE               *fp = NULL;
    char               buf[256];
    int                pid;
    int                running;
    char               cmd[256];
    

    /* use lsusb command check Logic C920 camera exist or not */
    fp = popen("lsusb | grep -v grep | grep C920", "r");
    if( !fp )
    {
        log_err("popen to check C920 failure: %s\n", strerror(errno));
        return -1;
    }

    memset(buf, 0, sizeof(buf));
    fgets(buf, sizeof(buf), fp);
    if( !strstr(buf, "C920") )
    {
        log_err("Logic C920 camera not exist\n");
        return -2;
    }
    log_nrml("Logic C920 camera exist\n");


    fp=popen("ps aux | grep mjpg_streamer | grep -v grep | awk '{print $2}'", "r");
    if( !fp )
    {
        log_err("popen to check mjpg_streamer failure: %s\n", strerror(errno));
        return -1;
    }

    memset(buf, 0, sizeof(buf));
    fgets(buf, sizeof(buf), fp);
    
    pid = atoi(buf);
    if( pid > 1 )
    {
        log_nrml("mjpg_streamer already working as pid[%d] now\n", pid);
        running = 1;
    }
    else
    {
        log_nrml("mjpg_streamer not running now\n");
        running = 0;
    }

    if( running && strcasestr(status, "off") )
    {
        log_warn("Stop mjpg_streamer working on C920 now\n");
        system("/bin/video stop");
        return 0;
    }

    if( !running && strcasestr(status, "on") )
    {
        log_nrml("Start mjpg_streamer working on C920 now\n");
        system("/bin/video start");
    }

    return 0;
}

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

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

    item = cJSON_GetObjectItem(root, "camera");
    if( !item )
    {
        log_err("cJSON_Parse get camera failure: %s\n", cJSON_GetErrorPtr());
        return ;
    }

    value = cJSON_PrintUnformatted(item);

    turn_camera(value);

    free(value);
}

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;
    cJSON                  *item;
    char                   *value;

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

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

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

    item = cJSON_GetObjectItem(root, "id");
    if( !item )
    {
        log_err("cJSON_Parse get ID failure: %s\n", cJSON_GetErrorPtr());
        goto OUT;
    }


    value = cJSON_PrintUnformatted(item);
    if( strcasecmp(value, ctx->id) )
    {
        free(value);
        goto OUT;
    }
    free(value);

    log_nrml("Subscriber[%s] receive message: '%s'\n", ctx->id, message->payload);
    proc_json_items(root); 

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


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

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

    /* set connnect to broker username and password  */
    if( strlen(ctx->uid)> 0  && strlen(ctx->pwd)> 0 )
        mosquitto_username_pw_set(mosq, ctx->uid, 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, ctx->host, ctx->port, ctx->keepalive) )
        {
            log_err("Subscriber connect to broker[%s:%d] failure: %s\n", ctx->host, ctx->port, strerror(errno)); 
            sleep(1);
            continue;
        }

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

    mosquitto_destroy(mosq);
    return NULL;
}