#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/event_groups.h"
#include "esp_system.h"
#include "esp_wifi.h"
#include "esp_event.h"
#include "esp_log.h"
#include "nvs_flash.h"
#include "esp_netif.h"
#include "lwip/err.h"
#include "lwip/sys.h"

const static char *TAG = "WIFI";
#define CONFIG_LOG_MAXIMUM_LEVEL 5

#define WIFI_SSID "Wokwi-GUEST"
#define WIFI_PASS ""

static EventGroupHandle_t wifi_event_group;
const int CONNECTED_BIT = BIT0;

// WiFi event handler
static void wifi_event_handler(void *arg, esp_event_base_t event_base,
                               int32_t event_id, void *event_data) {
    if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_START) {
        esp_wifi_connect(); // s4
    } else if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_DISCONNECTED) {
        xEventGroupClearBits(wifi_event_group, CONNECTED_BIT);
        esp_wifi_connect(); // s4
    } else if (event_base == IP_EVENT && event_id == IP_EVENT_STA_GOT_IP) {
        xEventGroupSetBits(wifi_event_group, CONNECTED_BIT);
    }
}

// Main task
void main_task(void *pvParameter) {
    esp_netif_ip_info_t ip_info;

    // wait for connection
    ESP_LOGI(TAG, "Waiting for connection to the Wi-Fi network...");
    xEventGroupWaitBits(wifi_event_group, CONNECTED_BIT, false, true, portMAX_DELAY);
    ESP_LOGI(TAG, "Connected!");

    // Get and print the local IP address
    esp_netif_get_ip_info(esp_netif_get_handle_from_ifkey("WIFI_STA_DEF"), &ip_info);
    ESP_LOGW(TAG, "IP Address:  " IPSTR "", IP2STR(&ip_info.ip));
    ESP_LOGW(TAG, "Subnet mask: " IPSTR "", IP2STR(&ip_info.netmask));
    ESP_LOGW(TAG, "Gateway:     " IPSTR "", IP2STR(&ip_info.gw));
    ESP_LOGI(TAG, "You can connect now to any web server online! :)");

    while (1) {
        vTaskDelay(1000 / portTICK_PERIOD_MS);
    }
}

// Main application
void app_main() {
    esp_log_level_set(TAG, ESP_LOG_VERBOSE);
    ESP_LOGI(TAG, "ESP-IDF version used: %s", IDF_VER);

    // Initialize NVS
    esp_err_t ret = nvs_flash_init();
    if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND) {
        ESP_ERROR_CHECK(nvs_flash_erase());
        ret = nvs_flash_init();
    }
    ESP_ERROR_CHECK(ret);

    // 1 - Wi-Fi/LwIP Init Phase
    // s1.1 Initialize the TCP/IP stack
    esp_netif_init();
    // s1.2 Create the default event loop
    ESP_ERROR_CHECK(esp_event_loop_create_default());
    // s1.3 Create the default Wi-Fi station
    esp_netif_create_default_wifi_sta();
    // s1.4 Initialize the Wi-Fi driver
    wifi_init_config_t wifi_init_config = WIFI_INIT_CONFIG_DEFAULT();
    ESP_ERROR_CHECK(esp_wifi_init(&wifi_init_config));
    // Create the event group to handle Wi-Fi events
    wifi_event_group = xEventGroupCreate();

    // 2 - Wi-Fi Configuration Phase
    ESP_ERROR_CHECK(esp_event_handler_instance_register(WIFI_EVENT,
                                                        ESP_EVENT_ANY_ID,
                                                        &wifi_event_handler,
                                                        NULL, NULL));
    ESP_ERROR_CHECK(esp_event_handler_instance_register(IP_EVENT,
                                                        IP_EVENT_STA_GOT_IP,
                                                        &wifi_event_handler,
                                                        NULL, NULL));

    // Configure Wi-Fi connection settings
    wifi_config_t wifi_config = {
        .sta = {
            .ssid = WIFI_SSID,
            .password = WIFI_PASS,
        },
    };

    // Set Wi-Fi mode to STA (Station)
    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
    ESP_ERROR_CHECK(esp_wifi_set_config(ESP_IF_WIFI_STA, &wifi_config));
    // 3 - Wi-Fi Start Phase
    ESP_ERROR_CHECK(esp_wifi_start());
    // Start the main task
    xTaskCreate(&main_task, "main_task", 2048, NULL, 5, NULL);
    ESP_LOGI(TAG, "Connecting to %s", WIFI_SSID);
}