#ifdef FRAMEWORK_espidf
// Copyright 2020 Lukas Haubaum
//
// Licensed under the GNU Affero General Public License, Version 3;
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at

//     https://www.gnu.org/licenses/agpl-3.0.html
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <string.h>

#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 "lwip/err.h"
#include "lwip/sys.h"

#include "ena-cwa.h"

#include "wifi.h"

#define WIFI_CONNECTED_BIT BIT0
#define WIFI_FAIL_BIT BIT1

static EventGroupHandle_t s_wifi_event_group;

static int s_retry_num = 0;

static bool connected = false;

void wifi_stop(void)
{
    connected = false;
    esp_wifi_stop();
    esp_wifi_deinit();
    esp_event_loop_delete_default();
}

static esp_err_t 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_DISCONNECTED:
        if (s_retry_num < WIFI_MAXIMUM_RETRY)
        {
	    esp_wifi_connect();
            s_retry_num++;
            ESP_LOGD(WIFI_LOG, "retry to connect to the AP");
	}
	else
	{
            xEventGroupSetBits(s_wifi_event_group, WIFI_FAIL_BIT);
	}
        ESP_LOGD(WIFI_LOG, "connect to the AP fail");
	connected = false;
        break;
    case SYSTEM_EVENT_STA_GOT_IP:
        s_retry_num = 0;
        xEventGroupSetBits(s_wifi_event_group, WIFI_CONNECTED_BIT);
        connected = true;

        heap_caps_check_integrity_all(true);
        break;
    default:
        ESP_LOGD(WIFI_LOG, "eventbase WIFI, eventid %d", event->event_id);
        break;
    }
    return ESP_OK;
}

void wifi_start(void)
{

    // init NVS for WIFI
    esp_err_t ret;
    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());
        ESP_ERROR_CHECK(nvs_flash_init());
    }

    s_wifi_event_group = xEventGroupCreate();

    ESP_ERROR_CHECK(esp_event_loop_create_default());

    tcpip_adapter_init();
    ESP_ERROR_CHECK(esp_event_loop_init(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 = WIFI_SSID,
            .password = WIFI_PASSWORD,
            /* Setting a password implies station will connect to all security modes including WEP/WPA.
             * However these modes are deprecated and not advisable to be used. Incase your Access point
             * doesn't support WPA2, these mode can be enabled by commenting below line */
            .threshold.authmode = WIFI_AUTH_WPA2_PSK,

            .pmf_cfg = {
                .capable = true,
                .required = false},
        },
    };
    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
    ESP_ERROR_CHECK(esp_wifi_set_config(ESP_IF_WIFI_STA, &wifi_config));
    ESP_ERROR_CHECK(esp_wifi_start());

    /* Waiting until either the connection is established (WIFI_CONNECTED_BIT) or connection failed for the maximum
     * number of re-tries (WIFI_FAIL_BIT). The bits are set by event_handler() (see above) */
    EventBits_t bits = xEventGroupWaitBits(s_wifi_event_group,
                                           WIFI_CONNECTED_BIT | WIFI_FAIL_BIT,
                                           pdFALSE,
                                           pdFALSE,
                                           portMAX_DELAY);

    /* xEventGroupWaitBits() returns the bits before the call returned, hence we can test which event actually
     * happened. */
    if (bits & WIFI_CONNECTED_BIT)
    {
        ESP_LOGV(WIFI_LOG, "connected to ap SSID:%s",
                 WIFI_SSID);
    }
    else if (bits & WIFI_FAIL_BIT)
    {
        ESP_LOGI(WIFI_LOG, "Failed to connect to SSID:%s",
                 WIFI_SSID);
    }
    else
    {
        ESP_LOGE(WIFI_LOG, "UNEXPECTED EVENT");
    }

#if 0
    /* The event will not be processed after unregister */
    ESP_ERROR_CHECK(esp_event_handler_instance_unregister(IP_EVENT, IP_EVENT_STA_GOT_IP, instance_got_ip));
    ESP_ERROR_CHECK(esp_event_handler_instance_unregister(WIFI_EVENT, ESP_EVENT_ANY_ID, instance_any_id));
    vEventGroupDelete(s_wifi_event_group);
#endif
}

bool wifi_is_connected(void)
{
    return connected;
}
#endif