/*
 * myMqtt.c
 *
 *  Created on: 25.11.2022
 *      Author: jonas
 */

#include "myMqtt.h"
#include <stdio.h>
#include <stdbool.h>
#include <stdint.h>
#include "esp_log.h"
#include "mqtt_client.h"
#include "challenge_com.h"
#include "challenge_nvs.h"
#include "McuUtility.h"

// tag for logging with ESP_LOG
static const char *TAG = "MY_MQTT";

// local cars
char _brokerIp[] = "255.255.255.255";  // max length of ip

// declarations
static void log_error_if_nonzero(const char *message, int error_code);
static void mqtt_event_handler(void *handler_args, esp_event_base_t base, int32_t event_id, void *event_data);

// variables
esp_mqtt_client_handle_t client;

bool MyMqtt_Init(void){
	char brokerUri[50];
	// get from NVS
	Challenge_Nvs_GetBrokerIpFromNVS(_brokerIp, sizeof(_brokerIp));
	McuUtility_strcpy((unsigned char*)brokerUri, sizeof(brokerUri), (unsigned char*)"mqtt://");
	McuUtility_strcat((unsigned char*)brokerUri, sizeof(brokerUri), (unsigned char*)_brokerIp);
	ESP_LOGI(TAG, "Connecting to Mqtt Broker URI '%s'", brokerUri);
	esp_mqtt_client_config_t mqtt_cfg = {
	        .uri = brokerUri,
	};
    client = esp_mqtt_client_init(&mqtt_cfg);
    /* The last argument may be used to pass data to the event handler, in this example mqtt_event_handler */
    esp_mqtt_client_register_event(client, ESP_EVENT_ANY_ID, mqtt_event_handler, NULL);
    esp_mqtt_client_register_event(client, MQTT_EVENT_DATA, Challenge_Com_ParseMqtt, NULL);  // ToDo: maybe make this configurable via parameter
    esp_err_t mqtt_error = esp_mqtt_client_start(client);

    // allow 1s to finish mqtt client to start
    vTaskDelay(1000);

    return mqtt_error == ESP_OK;
}

void MyMqtt_Deinit(void){
	esp_mqtt_client_destroy(client);
}

void MyMqtt_Publish(const char *topic, const char *data){
    int msg_id = esp_mqtt_client_publish(client, topic, data, 0, 1, 0);
    ESP_LOGI(TAG, "sent publish successful, msg_id=%d", msg_id);
}

void MyMqtt_Subscribe(const char *topic){
    int msg_id = esp_mqtt_client_subscribe(client, topic, 0);
    ESP_LOGI(TAG, "sent subscribe successful, msg_id=%d, success=%s", msg_id, msg_id==-1 ? "false" : "true");
}

char* MyMqtt_GetBrokerIP(void){
	return _brokerIp;
}

void MyMqtt_SetBrokerIP(char* ip){
	ESP_LOGI(TAG, "Set Broker IP to '%s'", ip);
	McuUtility_strcpy((unsigned char*)_brokerIp, sizeof(_brokerIp), (unsigned char*)ip);
	// store to NVS
	Challenge_Nvs_StoreBrokerIpToNVS(_brokerIp);
}


/***********/
/* HELPERS */
/***********/

static void log_error_if_nonzero(const char *message, int error_code)
{
    if (error_code != 0) {
        ESP_LOGE(TAG, "Last error %s: 0x%x", message, error_code);
    }
}

/*
 * @brief Event handler registered to receive MQTT events
 *
 *  This function is called by the MQTT client event loop.
 *
 * @param handler_args user data registered to the event.
 * @param base Event base for the handler(always MQTT Base in this example).
 * @param event_id The id for the received event.
 * @param event_data The data for the event, esp_mqtt_event_handle_t.
 */
static void mqtt_event_handler(void *handler_args, esp_event_base_t base, int32_t event_id, void *event_data)
{
    ESP_LOGD(TAG, "Event dispatched from event loop base=%s, event_id=%d", base, event_id);
    esp_mqtt_event_handle_t event = event_data;
    // unused: esp_mqtt_client_handle_t client = event->client;
    switch ((esp_mqtt_event_id_t)event_id) {
    case MQTT_EVENT_CONNECTED:
        ESP_LOGI(TAG, "MQTT_EVENT_CONNECTED");
        break;
    case MQTT_EVENT_DISCONNECTED:
        ESP_LOGI(TAG, "MQTT_EVENT_DISCONNECTED");
        break;

    case MQTT_EVENT_SUBSCRIBED:
        ESP_LOGI(TAG, "MQTT_EVENT_SUBSCRIBED, msg_id=%d", event->msg_id);
        break;

    case MQTT_EVENT_UNSUBSCRIBED:
        ESP_LOGI(TAG, "MQTT_EVENT_UNSUBSCRIBED, msg_id=%d", event->msg_id);
        break;

    case MQTT_EVENT_PUBLISHED:
        ESP_LOGI(TAG, "MQTT_EVENT_PUBLISHED, msg_id=%d", event->msg_id);
        break;

    case MQTT_EVENT_DATA:
        ESP_LOGI(TAG, "MQTT_EVENT_DATA");
        printf("TOPIC=%.*s\r\n", event->topic_len, event->topic);
        printf("DATA=%.*s\r\n", event->data_len, event->data);
        break;

    case MQTT_EVENT_ERROR:
        ESP_LOGI(TAG, "MQTT_EVENT_ERROR");
        if (event->error_handle->error_type == MQTT_ERROR_TYPE_TCP_TRANSPORT) {
            log_error_if_nonzero("reported from esp-tls", event->error_handle->esp_tls_last_esp_err);
            log_error_if_nonzero("reported from tls stack", event->error_handle->esp_tls_stack_err);
            log_error_if_nonzero("captured as transport's socket errno",  event->error_handle->esp_transport_sock_errno);
            ESP_LOGI(TAG, "Last errno string (%s)", strerror(event->error_handle->esp_transport_sock_errno));

        }
        break;

    default:
        ESP_LOGI(TAG, "Other event id:%d", event->event_id);
        break;
    }
}

/*********/
/* SHELL */
/*********/
#if PL_CONFIG_USE_SHELL
static uint8_t PrintStatus(const McuShell_StdIOType *io) {
  McuShell_SendStatusStr((unsigned char*)"mqtt", (unsigned char*)"ESP32 MQTT status\r\n", io->stdOut);
  McuShell_SendStatusStr((unsigned char*)"  ip", (unsigned char*)MyMqtt_GetBrokerIP(), io->stdOut);
  return ERR_OK;
}

static uint8_t PrintHelp(const McuShell_StdIOType *io) {
  McuShell_SendHelpStr((unsigned char*)"mqtt", (unsigned char*)"Group of ESP32 MQTT commands\r\n", io->stdOut);
  McuShell_SendHelpStr((unsigned char*)"  help|status", (unsigned char*)"Shows MQTT help or status\r\n", io->stdOut);
  McuShell_SendHelpStr((unsigned char*)"  setIp <ipv4>", (unsigned char*)"Sets the IP address of the MQTT broker\r\n", io->stdOut);
  McuShell_SendHelpStr((unsigned char*)"  publish <topic> <msg>", (unsigned char*)"Publishes a message to the given topic.\r\n", io->stdOut);
  return ERR_OK;
}

uint8_t MyMqtt_ParseShellCommand(const unsigned char* cmd, bool *handled, const McuShell_StdIOType *io) {
  if (McuUtility_strcmp((char*)cmd, (char*)McuShell_CMD_HELP)==0 || McuUtility_strcmp((char*)cmd, (char*)"mqtt help")==0) {
    *handled = TRUE;
    return PrintHelp(io);
  } else if (McuUtility_strcmp((char*)cmd, (char*)McuShell_CMD_STATUS)==0 || McuUtility_strcmp((char*)cmd, (char*)"mqtt status")==0) {
    *handled = TRUE;
    return PrintStatus(io);
  } else if (McuUtility_strncmp((char*)cmd,"mqtt setIp",sizeof("mqtt setIp")-1) == 0) { // contains
    *handled = TRUE;
    char ip[] = "255.255.255.255"; // maximum size of IP
    McuUtility_strcpy((unsigned char*)ip, sizeof(ip), (unsigned char *)cmd + strlen((char*)"mqtt setIp ")); // cut front
	McuUtility_strCutTail((unsigned char*)ip, (unsigned char*)"\0\0\0"); // cut tail
	MyMqtt_SetBrokerIP(ip);  // set ip
  }else if (McuUtility_strncmp((char*)cmd,"mqtt publish ",sizeof("mqtt publish ")-1) == 0){
	  *handled = TRUE;
	  cmd += sizeof("mqtt publish")-1;
	  // skip until double quotes (topic)
	  while(*cmd!='\"'){
		  cmd++;
	  }
	  uint8_t topic[128] = "";
	  uint8_t data[128] = "";
	  McuUtility_ScanDoubleQuotedString(&cmd, topic, sizeof(topic));
	  ESP_LOGI(TAG, "Parsed topic=%s", topic);
	  // skip to data
	  cmd++;
	  McuUtility_ScanDoubleQuotedString(&cmd, data, sizeof(data));
	  ESP_LOGI(TAG, "Parsed data=%s", data);
	  MyMqtt_Publish((char*)topic, (char*)data);
  }
  return ERR_OK;
}
#endif /* PL_CONFIG_USE_SHELL */