#include "esp_system.h"
#include "esp_wifi.h"
#include "esp_event.h"
#include "esp_log.h"
#include "nvs_flash.h"
 
#include "lwip/err.h"
#include "lwip/sys.h"

#include "app_lib_wifi_impl.h"

EventGroupHandle_t g_wifi_event_group;

static uint8_t s_retry_num = 0;
static const char *TAG = "APP_WIFI";

#define APP_WIFI_SSID CONFIG_APP_WIFI_SSID
#define APP_WIFI_PASS CONFIG_APP_WIFI_PASSWORD
#define APP_WIFI_RETR CONFIG_APP_WIFI_MAXIMUM_RETRY
#define APP_WIFI_INTV CONFIG_APP_WIFI_LISTEN_INTERVAL

#if CONFIG_APP_POWER_SAVE_MIN_MODEM
#define DEFAULT_PS_MODE WIFI_PS_MIN_MODEM

#elif CONFIG_APP_POWER_SAVE_MAX_MODEM
#define DEFAULT_PS_MODE WIFI_PS_MAX_MODEM

#elif CONFIG_APP_POWER_SAVE_NONE
#define DEFAULT_PS_MODE WIFI_PS_NONE

#else
#define DEFAULT_PS_MODE WIFI_PS_NONE

#endif

static void 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();
    } else if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_DISCONNECTED) {
        if (s_retry_num < APP_WIFI_RETR) {
            esp_wifi_connect();
            s_retry_num++;
            ESP_LOGI(TAG, "Connect attempt failed, retrying (%u/%u)...", s_retry_num, APP_WIFI_RETR);
        } else {
            xEventGroupSetBits(g_wifi_event_group, WIFI_ERROR_BIT);
            ESP_LOGI(TAG, "WiFi connection failed, no more retries scheduled.");
        }
    } else if (event_base == IP_EVENT && event_id == IP_EVENT_STA_GOT_IP) {
        ip_event_got_ip_t *event = (ip_event_got_ip_t *)event_data;
        ESP_LOGI(TAG, "Client IP:" IPSTR, IP2STR(&event->ip_info.ip));
        s_retry_num = 0;
        xEventGroupSetBits(g_wifi_event_group, WIFI_CONNECTED_BIT);
    }
}

void app_lib_init_wifi(void) {
    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);

    g_wifi_event_group = xEventGroupCreate();

    ESP_ERROR_CHECK(esp_netif_init());
    ESP_ERROR_CHECK(esp_event_loop_create_default());
    esp_netif_create_default_wifi_sta();

    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
    ESP_ERROR_CHECK(esp_wifi_init(&cfg));

    esp_event_handler_instance_t instance_any_id;
    esp_event_handler_instance_t instance_got_ip;
    ESP_ERROR_CHECK(esp_event_handler_instance_register(WIFI_EVENT, ESP_EVENT_ANY_ID, &event_handler, NULL, &instance_any_id));
    ESP_ERROR_CHECK(esp_event_handler_instance_register(WIFI_EVENT, IP_EVENT_STA_GOT_IP, &event_handler, NULL, &instance_got_ip));

    wifi_config_t wifi_config = {
        .sta = {
            .ssid = APP_WIFI_SSID,
            .password = APP_WIFI_PASS,
            .threshold.authmode = WIFI_AUTH_WPA2_PSK,
            .listen_interval = APP_WIFI_INTV,

            .pmf_cfg = {
                .capable = true,
                .required = false
            }
        }
    };

    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
    ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_STA, &wifi_config));
}

void app_lib_start_wifi(void) {
    ESP_ERROR_CHECK(esp_wifi_start());
}

void app_lib_stop_wifi(void) {
    ESP_ERROR_CHECK(esp_wifi_stop());
}