<?php

namespace Drupal\layout_builder\Plugin\Derivative;

use Drupal\Component\Plugin\Derivative\DeriverBase;
use Drupal\Component\Plugin\PluginBase;
use Drupal\Core\Entity\EntityFieldManagerInterface;
use Drupal\Core\Entity\EntityTypeBundleInfoInterface;
use Drupal\Core\Entity\EntityTypeManagerInterface;
use Drupal\Core\Entity\FieldableEntityInterface;
use Drupal\Core\Extension\ModuleHandlerInterface;
use Drupal\Core\Plugin\Context\EntityContextDefinition;
use Drupal\Core\Plugin\Discovery\ContainerDeriverInterface;
use Drupal\Core\StringTranslation\StringTranslationTrait;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Drupal\Core\Entity\EntityTypeRepositoryInterface;

/**
 * Provides entity field block definitions for every field.
 *
 * @internal
 *   Plugin derivers are internal.
 */
class ExtraFieldBlockDeriver extends DeriverBase implements ContainerDeriverInterface {

  use StringTranslationTrait;

  /**
   * The entity field manager.
   *
   * @var \Drupal\Core\Entity\EntityFieldManagerInterface
   */
  protected $entityFieldManager;

  /**
   * The entity type manager.
   *
   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
   */
  protected $entityTypeManager;

  /**
   * The entity type bundle info.
   *
   * @var \Drupal\Core\Entity\EntityTypeBundleInfoInterface
   */
  protected $entityTypeBundleInfo;

  /**
   * The entity type repository.
   *
   * @var \Drupal\Core\Entity\EntityTypeRepositoryInterface
   */
  protected $entityTypeRepository;

  /**
   * Constructs new FieldBlockDeriver.
   *
   * @param \Drupal\Core\Entity\EntityFieldManagerInterface $entity_field_manager
   *   The entity field manager.
   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
   *   The entity type manager.
   * @param \Drupal\Core\Entity\EntityTypeBundleInfoInterface $entity_type_bundle_info
   *   The entity type bundle info.
   * @param \Drupal\Core\Entity\EntityTypeRepositoryInterface $entity_type_repository
   *   The entity type repository.
   * @param \Drupal\Core\Extension\ModuleHandlerInterface $moduleHandler
   *   The module handler.
   */
  public function __construct(
    EntityFieldManagerInterface $entity_field_manager,
    EntityTypeManagerInterface $entity_type_manager,
    EntityTypeBundleInfoInterface $entity_type_bundle_info,
    EntityTypeRepositoryInterface $entity_type_repository,
    protected ModuleHandlerInterface $moduleHandler,
  ) {
    $this->entityFieldManager = $entity_field_manager;
    $this->entityTypeManager = $entity_type_manager;
    $this->entityTypeBundleInfo = $entity_type_bundle_info;
    $this->entityTypeRepository = $entity_type_repository;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, $base_plugin_id) {
    return new static(
      $container->get('entity_field.manager'),
      $container->get('entity_type.manager'),
      $container->get('entity_type.bundle.info'),
      $container->get('entity_type.repository'),
      $container->get('module_handler')
    );
  }

  /**
   * {@inheritdoc}
   */
  public function getDerivativeDefinitions($base_plugin_definition) {
    $entity_type_labels = $this->entityTypeRepository->getEntityTypeLabels();
    $enabled_bundle_ids = $this->bundleIdsWithLayoutBuilderDisplays();
    $expose_all_fields = $this->moduleHandler->moduleExists('layout_builder_expose_all_field_blocks');
    foreach ($this->entityTypeManager->getDefinitions() as $entity_type_id => $entity_type) {
      // Only process fieldable entity types.
      if (!$entity_type->entityClassImplements(FieldableEntityInterface::class)) {
        continue;
      }

      // If not loading everything, skip entity types that aren't included.
      if (!$expose_all_fields && !isset($enabled_bundle_ids[$entity_type_id])) {
        continue;
      }

      $bundles = $this->entityTypeBundleInfo->getBundleInfo($entity_type_id);
      foreach ($bundles as $bundle_id => $bundle) {
        // If not loading everything, skip bundle types that aren't included.
        if (!$expose_all_fields && !isset($enabled_bundle_ids[$entity_type_id][$bundle_id])) {
          continue;
        }

        $extra_fields = $this->entityFieldManager->getExtraFields($entity_type_id, $bundle_id);
        // Skip bundles without any extra fields.
        if (empty($extra_fields['display'])) {
          continue;
        }

        foreach ($extra_fields['display'] as $extra_field_id => $extra_field) {
          $derivative = $base_plugin_definition;

          $derivative['category'] = $this->t('@entity fields', ['@entity' => $entity_type_labels[$entity_type_id]]);

          $derivative['admin_label'] = $extra_field['label'];

          $context_definition = EntityContextDefinition::fromEntityType($entity_type)
            ->addConstraint('Bundle', [$bundle_id]);
          $derivative['context_definitions'] = [
            'entity' => $context_definition,
          ];

          $derivative_id = $entity_type_id . PluginBase::DERIVATIVE_SEPARATOR . $bundle_id . PluginBase::DERIVATIVE_SEPARATOR . $extra_field_id;
          $this->derivatives[$derivative_id] = $derivative;
        }
      }
    }
    return $this->derivatives;
  }

  /**
   * Gets a list of entity type and bundle tuples that have layout builder enabled.
   *
   * @return array
   *   A structured array with entity type as first key, bundle as second.
   */
  protected function bundleIdsWithLayoutBuilderDisplays(): array {
    /** @var \Drupal\layout_builder\Entity\LayoutEntityDisplayInterface[] $displays */
    $displays = $this->entityTypeManager->getStorage('entity_view_display')->loadByProperties([
      'third_party_settings.layout_builder.enabled' => TRUE,
    ]);
    $layout_bundles = [];
    foreach ($displays as $display) {
      $bundle = $display->getTargetBundle();
      $layout_bundles[$display->getTargetEntityTypeId()][$bundle] = $bundle;
    }
    return $layout_bundles;
  }

}
