#include "Networking.hpp"

#include <esp_log.h>
#include <esp_wifi.h>
#include <esp_event.h>
#include <esp_netif.h>
#include <nvs_flash.h>
#include <freertos/FreeRTOS.h>
#include <freertos/event_groups.h>
#include <string.h>

static const char* TAG = "Networking";

static EventGroupHandle_t s_wifi_event_group;
static const int CONNECTED_BIT = BIT0;
static int s_retries = 0;

static void wifi_event_handler(void*, esp_event_base_t base, int32_t id, void* data) {
    if(base == WIFI_EVENT && id == WIFI_EVENT_STA_START) {
        esp_wifi_connect();
    } else if(base == WIFI_EVENT && id == WIFI_EVENT_STA_DISCONNECTED) {
        if(s_retries < CONFIG_ESP_MAXIMUM_RETRY) {
            esp_wifi_connect();
            s_retries++;
            ESP_LOGI(TAG, "Reconnect attempt %d/%d", s_retries, CONFIG_ESP_MAXIMUM_RETRY);
        } else {
            ESP_LOGW(TAG, "Could not connect after %d attempts", CONFIG_ESP_MAXIMUM_RETRY);
        }
    } else if(base == IP_EVENT && id == IP_EVENT_STA_GOT_IP) {
        ip_event_got_ip_t* ev = (ip_event_got_ip_t*)data;
        ESP_LOGI(TAG, "Connected. IP: " IPSTR, IP2STR(&ev->ip_info.ip));
        s_retries = 0;
        xEventGroupSetBits(s_wifi_event_group, CONNECTED_BIT);
    }
}

void Networking::connectWifi() {
    /* NVS is required by the WiFi driver */
    esp_err_t err = nvs_flash_init();
    if(err == ESP_ERR_NVS_NO_FREE_PAGES || err == ESP_ERR_NVS_NEW_VERSION_FOUND) {
        nvs_flash_erase();
        nvs_flash_init();
    }

    err = esp_netif_init();
    if(err != ESP_OK && err != ESP_ERR_INVALID_STATE) {
        ESP_LOGE(TAG, "esp_netif_init: %s", esp_err_to_name(err));
    }

    err = esp_event_loop_create_default();
    if(err != ESP_OK && err != ESP_ERR_INVALID_STATE) {
        ESP_LOGE(TAG, "esp_event_loop_create_default: %s", esp_err_to_name(err));
    }

    esp_netif_create_default_wifi_sta();

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

    s_wifi_event_group = xEventGroupCreate();
    s_retries = 0;

    esp_event_handler_instance_t inst_any, inst_ip;
    esp_event_handler_instance_register(WIFI_EVENT, ESP_EVENT_ANY_ID,    wifi_event_handler, NULL, &inst_any);
    esp_event_handler_instance_register(IP_EVENT,   IP_EVENT_STA_GOT_IP, wifi_event_handler, NULL, &inst_ip);

    wifi_config_t wifi_cfg = {};
    strncpy((char*)wifi_cfg.sta.ssid,     CONFIG_ESP_WIFI_SSID,     sizeof(wifi_cfg.sta.ssid)     - 1);
    strncpy((char*)wifi_cfg.sta.password, CONFIG_ESP_WIFI_PASSWORD, sizeof(wifi_cfg.sta.password) - 1);
    wifi_cfg.sta.threshold.authmode = WIFI_AUTH_WPA2_PSK;

    esp_wifi_set_mode(WIFI_MODE_STA);
    esp_wifi_set_config(WIFI_IF_STA, &wifi_cfg);
    esp_wifi_start();

    EventBits_t bits = xEventGroupWaitBits(s_wifi_event_group, CONNECTED_BIT,
                                           pdFALSE, pdFALSE, pdMS_TO_TICKS(30000));
    if(!(bits & CONNECTED_BIT)) {
        ESP_LOGW(TAG, "WiFi not connected after 30 s — continuing without network");
    }

    vEventGroupDelete(s_wifi_event_group);
    s_wifi_event_group = NULL;
}

bool Networking::isConnected() const {
    wifi_ap_record_t ap;
    return esp_wifi_sta_get_ap_info(&ap) == ESP_OK;
}