// Copyright 2021 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at

//     http://www.apache.org/licenses/LICENSE-2.0
//
// 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 <stdio.h>
#include <string.h>

#include "esp_check.h"
#include "esp_err.h"
#include "esp_event.h"
#include "esp_log.h"
#include "esp_netif.h"
#include "esp_netif_ip_addr.h"
#include "esp_netif_net_stack.h"
#include "esp_openthread.h"
#include "esp_openthread_border_router.h"
#include "esp_openthread_lock.h"
#include "esp_openthread_netif_glue.h"
#include "esp_openthread_types.h"
#include "esp_ot_config.h"
#include "esp_vfs_eventfd.h"
#include "esp_wifi.h"
#include "mdns.h"
#include "nvs_flash.h"
#include "protocol_examples_common.h"
#include "sdkconfig.h"
#include "driver/uart.h"
#include "freertos/FreeRTOS.h"
#include "freertos/portmacro.h"
#include "freertos/task.h"
#include "hal/uart_types.h"
#include "openthread/border_router.h"
#include "openthread/cli.h"
#include "openthread/dataset.h"
#include "openthread/dataset_ftd.h"
#include "openthread/dataset_updater.h"
#include "openthread/error.h"
#include "openthread/instance.h"
#include "openthread/ip6.h"
#include "openthread/tasklet.h"
#include "openthread/thread.h"
#include "openthread/thread_ftd.h"

#define TAG "esp_ot_br"

static int hex_digit_to_int(char hex)
{
    if ('A' <= hex && hex <= 'F') {
        return 10 + hex - 'A';
    }
    if ('a' <= hex && hex <= 'f') {
        return 10 + hex - 'a';
    }
    if ('0' <= hex && hex <= '9') {
        return hex - '0';
    }
    return -1;
}

static size_t hex_string_to_binary(const char *hex_string, uint8_t *buf, size_t buf_size)
{
    int num_char = strlen(hex_string);

    if (num_char != buf_size * 2) {
        return 0;
    }
    for (size_t i = 0; i < num_char; i += 2) {
        int digit0 = hex_digit_to_int(hex_string[i]);
        int digit1 = hex_digit_to_int(hex_string[i + 1]);

        if (digit0 < 0 || digit1 < 0) {
            return 0;
        }
        buf[i / 2] = (digit0 << 4) + digit1;
    }

    return buf_size;
}

static void create_config_network(otInstance *instance)
{
    otOperationalDataset dataset;
    uint16_t network_name_len = strnlen(CONFIG_OPENTHREAD_NETWORK_NAME, OT_NETWORK_NAME_MAX_SIZE + 1);

    assert(network_name_len <= OT_NETWORK_NAME_MAX_SIZE);

    if (otDatasetCreateNewNetwork(instance, &dataset) != OT_ERROR_NONE) {
        ESP_LOGE(TAG, "Failed to create OpenThread network dataset.");
        abort();
    }
    dataset.mChannel = CONFIG_OPENTHREAD_NETWORK_CHANNEL;
    dataset.mComponents.mIsChannelPresent = true;
    dataset.mPanId = CONFIG_OPENTHREAD_NETWORK_PANID;
    dataset.mComponents.mIsPanIdPresent = true;
    memcpy(dataset.mNetworkName.m8, CONFIG_OPENTHREAD_NETWORK_NAME, network_name_len);
    dataset.mComponents.mIsNetworkNamePresent = true;
    if (hex_string_to_binary(CONFIG_OPENTHREAD_NETWORK_EXTPANID, dataset.mExtendedPanId.m8,
                             sizeof(dataset.mExtendedPanId.m8)) != sizeof(dataset.mExtendedPanId.m8)) {
        ESP_LOGE(TAG, "Cannot convert OpenThread extended pan id. Please double-check your config.");
        abort();
    }
    dataset.mComponents.mIsExtendedPanIdPresent = true;
    if (hex_string_to_binary(CONFIG_OPENTHREAD_NETWORK_MASTERKEY, dataset.mNetworkKey.m8,
                             sizeof(dataset.mNetworkKey.m8)) != sizeof(dataset.mNetworkKey.m8)) {
        ESP_LOGE(TAG, "Cannot convert OpenThread master key. Please double-check your config.");
        abort();
    }
    dataset.mComponents.mIsNetworkKeyPresent = true;
    if (hex_string_to_binary(CONFIG_OPENTHREAD_NETWORK_PSKC, dataset.mPskc.m8, sizeof(dataset.mPskc.m8)) !=
            sizeof(dataset.mPskc.m8)) {
        ESP_LOGE(TAG, "Cannot convert OpenThread pre-shared commissioner key. Please double-check your config.");
        abort();
    }
    dataset.mComponents.mIsPskcPresent = true;
    dataset.mComponents.mIsMeshLocalPrefixPresent = false;
    if (otDatasetSetActive(instance, &dataset) != OT_ERROR_NONE) {
        ESP_LOGE(TAG, "Failed to set OpenThread active dataset.");
        abort();
    }
    if (otBorderRouterRegister(instance) != OT_ERROR_NONE) {
        ESP_LOGE(TAG, "Failed to register border router.");
        abort();
    }
    if (otIp6SetEnabled(instance, true) != OT_ERROR_NONE) {
        ESP_LOGE(TAG, "Failed to enable OpenThread IP6 link");
        abort();
    }
    if (otThreadSetEnabled(instance, true) != OT_ERROR_NONE) {
        ESP_LOGE(TAG, "Failed to enable OpenThread");
        abort();
    }
    return;
}

static void ot_task_worker(void *aContext)
{
    esp_openthread_platform_config_t config = {
        .radio_config = ESP_OPENTHREAD_DEFAULT_RADIO_CONFIG(),
        .host_config = ESP_OPENTHREAD_DEFAULT_HOST_CONFIG(),
        .port_config = ESP_OPENTHREAD_DEFAULT_PORT_CONFIG(),
    };

    esp_netif_config_t cfg = ESP_NETIF_DEFAULT_OPENTHREAD();
    esp_netif_t *openthread_netif = esp_netif_new(&cfg);
    assert(openthread_netif != NULL);

    // Initialize the OpenThread stack
    ESP_ERROR_CHECK(esp_openthread_init(&config));

    // Initialize border routing features
    ESP_ERROR_CHECK(esp_netif_attach(openthread_netif, esp_openthread_netif_glue_init(&config)));
    ESP_ERROR_CHECK(esp_openthread_border_router_init(get_example_netif()));

    esp_openthread_lock_acquire(portMAX_DELAY);
    create_config_network(esp_openthread_get_instance());
    esp_openthread_lock_release();

    // Run the main loop
    esp_openthread_launch_mainloop();

    // Clean up
    esp_netif_destroy(openthread_netif);
    esp_openthread_netif_glue_deinit();
    esp_vfs_eventfd_unregister();
    vTaskDelete(NULL);
}

void app_main(void)
{
    // Used eventfds:
    // * netif
    // * task queue
    esp_vfs_eventfd_config_t eventfd_config = {
        .max_fds = 2,
    };
    ESP_ERROR_CHECK(esp_vfs_eventfd_register(&eventfd_config));

    ESP_ERROR_CHECK(nvs_flash_init());
    ESP_ERROR_CHECK(esp_netif_init());
    ESP_ERROR_CHECK(esp_event_loop_create_default());
    ESP_ERROR_CHECK(example_connect());
    ESP_ERROR_CHECK(esp_wifi_set_ps(WIFI_PS_NONE));
    ESP_ERROR_CHECK(mdns_init());
    ESP_ERROR_CHECK(mdns_hostname_set("esp-ot-br"));
    xTaskCreate(ot_task_worker, "ot_br_main", 20480, xTaskGetCurrentTaskHandle(), 5, NULL);
}