#include <stdio.h>
#include <stdint.h>
#include <stddef.h>
#include <string.h>
#include "esp_wifi.h"
#include "esp_system.h"
#include "nvs_flash.h"
#include "esp_event.h"
#include "esp_netif.h"
#include "esp_log.h"
#include "mqtt_client.h"
#include "esp_tls.h"
#include "esp_ota_ops.h"
#include "my_data.h"

static const char *TAG = "MQTT_TCP";

extern const uint8_t mqtt_eclipseprojects_io_pem_start[]   asm("_binary_mqtt_eclipseprojects_io_pem_start");
extern const uint8_t mqtt_eclipseprojects_io_pem_end[]   asm("_binary_mqtt_eclipseprojects_io_pem_end");

static void wifi_event_handler(void *event_handler_arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
{
    switch (event_id)
    {
    case WIFI_EVENT_STA_START:
        printf("WiFi connecting ... \n");
        break;
    case WIFI_EVENT_STA_CONNECTED:
        printf("WiFi connected ... \n");
        break;
    case WIFI_EVENT_STA_DISCONNECTED:
        printf("WiFi lost connection ... \n");
        break;
    case IP_EVENT_STA_GOT_IP:
        printf("WiFi got IP ... \n\n");
        break;
    default:
        break;
    }
}

void wifi_connection()
{
    // 1 - Wi-Fi/LwIP Init Phase
    esp_netif_init();                    // TCP/IP initiation 					s1.1
    esp_event_loop_create_default();     // event loop 			                s1.2
    esp_netif_create_default_wifi_sta(); // WiFi station 	                    s1.3
    wifi_init_config_t wifi_initiation = WIFI_INIT_CONFIG_DEFAULT();
    esp_wifi_init(&wifi_initiation); // 					                    s1.4
    // 2 - Wi-Fi Configuration Phase
    esp_event_handler_register(WIFI_EVENT, ESP_EVENT_ANY_ID, wifi_event_handler, NULL);
    esp_event_handler_register(IP_EVENT, IP_EVENT_STA_GOT_IP, wifi_event_handler, NULL);
    wifi_config_t wifi_configuration = {
        .sta = {
            .ssid = SSID,
            .password = PASS}};
    esp_wifi_set_config(ESP_IF_WIFI_STA, &wifi_configuration);
    // 3 - Wi-Fi Start Phase
    esp_wifi_start();
    // 4- Wi-Fi Connect Phase
    esp_wifi_connect();
}

static esp_err_t mqtt_event_handler_cb(esp_mqtt_event_handle_t event)
{
    esp_mqtt_client_handle_t client = event->client;
    switch (event->event_id)
    {
    case MQTT_EVENT_CONNECTED:
        ESP_LOGI(TAG, "MQTT_EVENT_CONNECTED");
        esp_mqtt_client_subscribe(client, "my_topic", 0);
        esp_mqtt_client_publish(client, "my_topic", "Hi to all from ESP32 .........", 0, 1, 0);
        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("\nTOPIC=%.*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");
        break;
    default:
        ESP_LOGI(TAG, "Other event id:%d", event->event_id);
        break;
    }
    return ESP_OK;
}

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);
    mqtt_event_handler_cb(event_data);
}

static void mqtt_app_start(void)
{
    esp_mqtt_client_config_t mqtt_cfg = {
        .uri = "mqtts://test.mosquitto.org:8883",
        .cert_pem = (const char *)mqtt_eclipseprojects_io_pem_start,
    };
    esp_mqtt_client_handle_t client = esp_mqtt_client_init(&mqtt_cfg);
    esp_mqtt_client_register_event(client, ESP_EVENT_ANY_ID, mqtt_event_handler, client);
    esp_mqtt_client_start(client);
}

void app_main(void)
{
    nvs_flash_init();
    wifi_connection();

    vTaskDelay(2000 / portTICK_PERIOD_MS);
    printf("WIFI was initiated ...........\n");

    mqtt_app_start();
}