#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_loop.h"

#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/semphr.h"
#include "freertos/queue.h"
#include "freertos/event_groups.h"

#include "esp_log.h"
#include "mqtt.h"

#define CONFIG_WIFI_SSID "********"
#define CONFIG_WIFI_PASSWORD "********"

const char *LOG_TAG = "MQTT_ESP32";

void connected_cb(mqtt_client *self, mqtt_event_data_t *params) {
    mqtt_client *client = (mqtt_client *)self;
    mqtt_subscribe(client, "/mqtt-esp32", 0);
    mqtt_publish(client, "/mqtt-esp32", "Hello World!", 11, 0, 0);
}
void disconnected_cb(mqtt_client *self, mqtt_event_data_t *params) {

}
void reconnect_cb(mqtt_client *self, mqtt_event_data_t *params) {

}
void subscribe_cb(mqtt_client *self, mqtt_event_data_t *params){
    ESP_LOGI(LOG_TAG, "Subscribe ok, test publish msg");
    mqtt_client *client = (mqtt_client *)self;
    mqtt_publish(client, "/mqtt-esp32", "abcde", 5, 0, 0);
}

void publish_cb(mqtt_client *self, mqtt_event_data_t *params){

}
void data_cb(mqtt_client *self, mqtt_event_data_t *event_data) {
    if(event_data->data_offset == 0) {
        char *topic = malloc(event_data->topic_length + 1);
        memcpy(topic, event_data->topic, event_data->topic_length);
        topic[event_data->topic_length] = 0;
        ESP_LOGI(LOG_TAG, "Received data for topic: %s", topic);
        free(topic);
    }
    char *data = malloc(event_data->data_length + 1);
    memcpy(data, event_data->data, event_data->data_length);
    data[event_data->data_length] = 0;
    ESP_LOGI(LOG_TAG, "Received data[%d/%d bytes]",
             event_data->data_length + event_data->data_offset,
             event_data->data_total_length);
    ESP_LOGI(LOG_TAG, "Data: %s",  (char *)(event_data->data));
    free(data);
}

mqtt_settings settings = {
    .host = "iot.eclipse.org",
#if defined(CONFIG_MQTT_SECURITY_ON)
    .port = 8883, // encrypted
#else
    .port = 1883, // unencrypted
#endif
    .client_id = "some_client_id",
    .username = "",
    .password = "",
    .clean_session = 0,
    .keepalive = 120,
    .lwt_topic = "/lwt",
    .lwt_msg = "offline",
    .lwt_qos = 0,
    .lwt_retain = 0,
    .connected_cb = connected_cb,
    .disconnected_cb = disconnected_cb,
    .subscribe_cb = subscribe_cb,
    .publish_cb = publish_cb,
    .data_cb = data_cb
};



esp_err_t wifi_event_handler(void *ctx, system_event_t *event) {
    switch(event->event_id) {
        case SYSTEM_EVENT_STA_START:
            esp_wifi_connect();
            break;
        case SYSTEM_EVENT_STA_GOT_IP:
            mqtt_start(&settings);
            break;
        case SYSTEM_EVENT_STA_DISCONNECTED:
            esp_wifi_connect();
            mqtt_stop();
            break;
        default:
            break;
    }
    return ESP_OK;
}

void wifi_conn_init(void) {
    tcpip_adapter_init();
    ESP_ERROR_CHECK(esp_event_loop_init(wifi_event_handler, NULL));
    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
    ESP_ERROR_CHECK(esp_wifi_init(&cfg));
    ESP_ERROR_CHECK(esp_wifi_set_storage(WIFI_STORAGE_RAM));
    wifi_config_t wifi_config = {
        .sta = {
            .ssid = CONFIG_WIFI_SSID,
            .password = CONFIG_WIFI_PASSWORD,
        },
    };
    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
    ESP_ERROR_CHECK(esp_wifi_set_config(ESP_IF_WIFI_STA, &wifi_config));
    ESP_LOGI(LOG_TAG, "start the WIFI SSID:[%s] password:[%s]", CONFIG_WIFI_SSID, "******");
    ESP_ERROR_CHECK(esp_wifi_start());
}

void app_main() {
    ESP_LOGI(LOG_TAG, "Starting");
    nvs_flash_init();
    wifi_conn_init();
}