// SDK
#include "esp_err.h"
#include "esp_eth.h"
#include "esp_eth_driver.h"
#include "esp_event.h"
#include "esp_log.h"
#include "esp_netif.h"
#include "esp_system.h"
#include "ethernet_init.h"

// Project includes
#include "types.hpp"

internal constexpr char kLogEthernet[] = "ETH";
internal constexpr char kNetifDescEth[] = "eth0";

internal esp_eth_handle_t *s_eth_handles = nullptr;
internal uint8_t s_eth_count = 0;
internal esp_eth_netif_glue_handle_t s_eth_glue = nullptr;
internal esp_netif_t *s_eth_netif = nullptr;
internal SemaphoreHandle_t s_semph_get_ip_addrs = nullptr;

void eth_on_got_ip(void *arg, esp_event_base_t event_base, int32_t event_id,
                   void *event_data) {
  ip_event_got_ip_t *event = (ip_event_got_ip_t *)event_data;
  bool isEthernetNetif =
      strncmp(kNetifDescEth, esp_netif_get_desc(event->esp_netif),
              strlen(kNetifDescEth) - 1) == 0;
  if (!isEthernetNetif) {
    return;
  }
  ESP_LOGI(kLogEthernet, "Got IPv4 event: Interface \"%s\" address: " IPSTR,
           esp_netif_get_desc(event->esp_netif), IP2STR(&event->ip_info.ip));
  xSemaphoreGive(s_semph_get_ip_addrs);
}

void teardown_ethernet() {
  if (s_semph_get_ip_addrs != nullptr) {
    vSemaphoreDelete(s_semph_get_ip_addrs);
    s_semph_get_ip_addrs = nullptr;
  }

  if (s_eth_netif) {

    ESP_ERROR_CHECK(esp_event_handler_unregister(IP_EVENT, IP_EVENT_ETH_GOT_IP,
                                                 &eth_on_got_ip));
    ESP_ERROR_CHECK(esp_eth_stop(s_eth_handles[0]));
    ESP_ERROR_CHECK(esp_eth_del_netif_glue(s_eth_glue));
    esp_netif_destroy(s_eth_netif);
    ethernet_deinit_all(s_eth_handles);
  }

  s_eth_glue = nullptr;
  s_eth_netif = nullptr;
  s_eth_handles = nullptr;
  s_eth_count = 0;

  esp_netif_deinit();
}

internal esp_err_t connect_ethernet(bool blockUntilIPAcquired) {
  s_semph_get_ip_addrs = xSemaphoreCreateBinary();
  if (s_semph_get_ip_addrs == NULL) {
    return ESP_ERR_NO_MEM;
  }
  // Connection is split in two steps. First we open the connection and ask for
  // an ip. Second a semaphor will block until the ip is acquired. If we dont
  // block then the user have to verify the semaphore before continuing.
  ESP_ERROR_CHECK(esp_netif_init());
  ESP_ERROR_CHECK(ethernet_init_all(&s_eth_handles, &s_eth_count));

  esp_netif_inherent_config_t esp_netif_config =
      ESP_NETIF_INHERENT_DEFAULT_ETH();
  // Warning: the interface desc is used in tests to capture actual connection
  // details (IP, gw, mask)
  esp_netif_config.if_desc = kNetifDescEth;
  esp_netif_config.route_prio = 64;
  esp_netif_config_t netif_config = {.base = &esp_netif_config,
                                     .driver = nullptr,
                                     .stack = ESP_NETIF_NETSTACK_DEFAULT_ETH};
  s_eth_netif = esp_netif_new(&netif_config);

  s_eth_glue = esp_eth_new_netif_glue(s_eth_handles[0]);
  esp_netif_attach(s_eth_netif, s_eth_glue);

  // Register user defined event handlers
  ESP_ERROR_CHECK(esp_event_handler_register(IP_EVENT, IP_EVENT_ETH_GOT_IP,
                                             &eth_on_got_ip, NULL));

  ESP_ERROR_CHECK(esp_eth_start(s_eth_handles[0]));

  // Will teardown connection properly on shutdown
  ESP_ERROR_CHECK(esp_register_shutdown_handler(&teardown_ethernet));

  if (blockUntilIPAcquired) {
    ESP_LOGI(kLogEthernet, "Waiting for IP address.");
    xSemaphoreTake(s_semph_get_ip_addrs, portMAX_DELAY);
  }

  return ESP_OK;
}

void disconnect_ethernet() {
  teardown_ethernet();
  ESP_ERROR_CHECK(esp_unregister_shutdown_handler(&teardown_ethernet));
}

internal esp_err_t check_ethernet_connection(uint32_t timeoutSeconds) {
  ESP_LOGI(kLogEthernet, "Waiting for IP address for %d seconds.",
           timeoutSeconds);
  if (xSemaphoreTake(s_semph_get_ip_addrs,
                     pdMS_TO_TICKS(timeoutSeconds * 1000))) {
    return ESP_OK;
  } else {
    return ESP_ERR_TIMEOUT;
  }
}