Add ancestor condition.

src/Plugin/Condition/NodeHasAncestor.php

@@ -0,0 +1,198 @@
+<?php
+
+namespace Drupal\islandora\Plugin\Condition;
+
+use Drupal\Core\Condition\ConditionPluginBase;
+use Drupal\Core\Entity\ContentEntityInterface;
+use Drupal\Core\Entity\EntityFieldManagerInterface;
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\islandora\IslandoraUtils;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Condition to see if a node has an ancestor.
+ *
+ * @Condition(
+ *   id = "node_has_ancestor",
+ *   label = @Translation("Node has ancestor"),
+ *   context_definitions = {
+ *     "node" = @ContextDefinition("entity:node", required = TRUE , label = @Translation("node"))
+ *   }
+ * )
+ */
+class NodeHasAncestor extends ConditionPluginBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * Drupal's entity type manager.
+   *
+   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
+   */
+  protected EntityTypeManagerInterface $entityTypeManager;
+
+  /**
+   * Constructor for the ancestor condition.
+   *
+   * @param array $configuration
+   *   The plugin configuration, i.e. an array with configuration values keyed
+   *   by configuration option name. The special key 'context' may be used to
+   *   initialize the defined contexts by setting it to an array of context
+   *   values keyed by context names.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
+   *   The Drupal entity type manager.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityTypeManagerInterface $entity_type_manager) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->entityTypeManager = $entity_type_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('entity_type.manager'),
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration(): array {
+    return parent::defaultConfiguration() + [
+      'ancestor_nids' => FALSE,
+      'parent_reference_field' => IslandoraUtils::MEMBER_OF_FIELD,
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
+    $default_nids = FALSE;
+    if ($this->configuration['ancestor_nids']) {
+      $default_nids = array_map(function ($nid) {
+        return $this->entityTypeManager->getStorage('node')->load($nid);
+      }, $this->configuration['ancestor_nids']);
+    }
+    $form['ancestor_nids'] = [
+      '#type' => 'entity_autocomplete',
+      '#title' => $this->t('Parent node(s)'),
+      '#default_value' => $default_nids,
+      '#required' => TRUE,
+      '#description' => $this->t("Can be a collection node, compound object or paged content. Accepts multiple values separated by a comma."),
+      '#target_type' => 'node',
+      '#tags' => TRUE,
+    ];
+
+    $options = [];
+    $reference_fields = $this->entityTypeManager->getStorage('field_storage_config')->loadByProperties([
+      'type' => 'entity_reference',
+      'settings' => [
+        'target_type' => 'node',
+      ],
+    ]);
+    foreach ($reference_fields as $field) {
+      $options[$field->get('field_name')] = $field->get('field_name');
+    }
+    $form['parent_reference_field'] = [
+      '#type' => 'select',
+      '#title' => $this->t('Direct parent reference'),
+      '#options' => $options,
+      '#default_value' => $this->configuration['parent_reference_field'],
+      '#required' => TRUE,
+      '#description' => $this->t('Field that contains the reference to its parent node.'),
+    ];
+
+    return parent::buildConfigurationForm($form, $form_state);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
+    // Entity autocomplete store things with target IDs, for convenience just
+    // store the plain nid.
+    $this->configuration['ancestor_nids'] = array_map(function ($nid) {
+      return $nid['target_id'];
+    }, $form_state->getValue('ancestor_nids'));
+    $this->configuration['parent_reference_field'] = $form_state->getValue('parent_reference_field');
+    parent::submitConfigurationForm($form, $form_state);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function evaluate() {
+    if (empty($this->configuration['ancestor_nids']) && !$this->isNegated()) {
+      return TRUE;
+    }
+
+    $node = $this->getContextValue('node');
+    if (!$node) {
+      return FALSE;
+    }
+
+    $ancestors = [];
+    $this->findAncestors($node, $ancestors);
+    return !empty(array_intersect($this->configuration['ancestor_nids'], $ancestors));
+  }
+
+  /**
+   * Recursively finds ancestors of an entity.
+   *
+   * @param \Drupal\Core\Entity\ContentEntityInterface $entity
+   *  The entity being checked.
+   * @param array $ancestors
+   *  The array of ancestors, passed by reference.
+   */
+  protected function findAncestors(ContentEntityInterface $entity, array &$ancestors): void {
+    $parents = $this->getParents($entity);
+    foreach ($parents as $parent) {
+      if (!isset($ancestors[$parent->id()])) {
+        $ancestors[$parent->id()] = $parent->id();
+        $this->findAncestors($parent, $ancestors);
+      }
+    }
+  }
+
+  /**
+   * Helper that gets the immediate parents of a node.
+   *
+   * @param \Drupal\Core\Entity\ContentEntityInterface $entity
+   *   The entity being checked.
+   *
+   * @return array
+   *   An array of entity objects keyed by field item deltas.
+   */
+  protected function getParents(ContentEntityInterface $entity): array {
+    if ($entity->hasField($this->configuration['parent_reference_field'])) {
+      $field = $entity->get($this->configuration['parent_reference_field']);
+      if (!$field->isEmpty()) {
+        return $field->referencedEntities();
+      }
+    }
+    return [];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function summary() {
+    if (!empty($this->configuration['negate'])) {
+      return $this->t('The node does not have node @nid as one of its ancestors.', ['@nid' => $this->configuration['ancestor_nids']]);
+    }
+    else {
+      return $this->t('The node has node @nid as one of its ancestors.', ['@nid' => $this->configuration['ancestor_nids']]);
+    }
+  }
+
+}