<?php

/**
 * @file
 * Contains farm_birth.module.
 */

use Drupal\Core\Entity\Display\EntityViewDisplayInterface;
use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Entity\EntityTypeInterface;
use Drupal\Core\Field\Entity\BaseFieldOverride;
use Drupal\Core\Url;

/**
 * Implements hook_ENTITY_TYPE_view_alter().
 */
function farm_birth_asset_view_alter(array &$build, EntityInterface $entity, EntityViewDisplayInterface $display) {

  // Only alter animal assets.
  if ($entity->bundle() != 'animal') {
    return;
  }

  // Add a link to the asset's birth log.
  if (!empty($build['birthdate'][0])) {
    /** @var \Drupal\Core\Entity\EntityStorageInterface $log_storage */
    $log_storage = \Drupal::service('entity_type.manager')->getStorage('log');
    $log_ids = $log_storage->getQuery()
      ->accessCheck(TRUE)
      ->condition('type', 'birth')
      ->condition('asset', $entity->id())
      ->execute();

    // Render a link to the log with a title of the timestamp field value.
    if (!empty($log_ids)) {
      $title = $build['birthdate'][0];
      $build['birthdate'][0] = [
        '#type' => 'link',
        '#title' => $title,
        '#url' => Url::fromRoute('entity.log.canonical', ['log' => reset($log_ids)]),
      ];
    }
  }
}

/**
 * Implements hook_entity_bundle_field_info().
 */
function farm_birth_entity_bundle_field_info(EntityTypeInterface $entity_type, $bundle, array $base_field_definitions) {
  $fields = [];

  // Add the UniqueBirthLog validation constraint to the asset field of birth
  // logs. We need to do this via hook_entity_bundle_field_info() instead of
  // hook_entity_field_info_alter() because this module also provides a
  // BaseFieldOverride for the asset field, and there is a Drupal core issue
  // that prevents these from working together normally.
  // @see https://www.drupal.org/project/drupal/issues/3193351
  if ($entity_type->id() == 'log' && $bundle == 'birth') {
    $fields['asset'] = BaseFieldOverride::loadByName($entity_type->id(), $bundle, 'asset') ?: clone $base_field_definitions['asset'];
    $fields['asset']->addConstraint('UniqueBirthLog');
  }

  return $fields;
}