<?php

namespace Drupal\block_content\Entity;

use Drupal\block_content\Access\RefinableDependentAccessTrait;
use Drupal\Core\Entity\EditorialContentEntityBase;
use Drupal\Core\Entity\EntityStorageInterface;
use Drupal\Core\Entity\EntityTypeInterface;
use Drupal\Core\Field\BaseFieldDefinition;
use Drupal\block_content\BlockContentInterface;

/**
 * Defines the content block entity class.
 *
 * @ContentEntityType(
 *   id = "block_content",
 *   label = @Translation("Content block"),
 *   label_collection = @Translation("Content blocks"),
 *   label_singular = @Translation("content block"),
 *   label_plural = @Translation("content blocks"),
 *   label_count = @PluralTranslation(
 *     singular = "@count content block",
 *     plural = "@count content blocks",
 *   ),
 *   bundle_label = @Translation("Block type"),
 *   handlers = {
 *     "storage" = "Drupal\Core\Entity\Sql\SqlContentEntityStorage",
 *     "storage_schema" = "Drupal\block_content\BlockContentStorageSchema",
 *     "access" = "Drupal\block_content\BlockContentAccessControlHandler",
 *     "list_builder" = "Drupal\block_content\BlockContentListBuilder",
 *     "view_builder" = "Drupal\block_content\BlockContentViewBuilder",
 *     "views_data" = "Drupal\block_content\BlockContentViewsData",
 *     "form" = {
 *       "add" = "Drupal\block_content\BlockContentForm",
 *       "edit" = "Drupal\block_content\BlockContentForm",
 *       "delete" = "Drupal\block_content\Form\BlockContentDeleteForm",
 *       "default" = "Drupal\block_content\BlockContentForm",
 *       "revision-delete" = \Drupal\Core\Entity\Form\RevisionDeleteForm::class,
 *       "revision-revert" = \Drupal\Core\Entity\Form\RevisionRevertForm::class,
 *     },
 *     "route_provider" = {
 *       "revision" = \Drupal\Core\Entity\Routing\RevisionHtmlRouteProvider::class,
 *     },
 *     "translation" = "Drupal\block_content\BlockContentTranslationHandler"
 *   },
 *   admin_permission = "administer block content",
 *   collection_permission = "access block library",
 *   base_table = "block_content",
 *   revision_table = "block_content_revision",
 *   data_table = "block_content_field_data",
 *   revision_data_table = "block_content_field_revision",
 *   show_revision_ui = TRUE,
 *   links = {
 *     "canonical" = "/admin/content/block/{block_content}",
 *     "delete-form" = "/admin/content/block/{block_content}/delete",
 *     "edit-form" = "/admin/content/block/{block_content}",
 *     "collection" = "/admin/content/block",
 *     "create" = "/block",
 *     "revision-delete-form" = "/admin/content/block/{block_content}/revision/{block_content_revision}/delete",
 *     "revision-revert-form" = "/admin/content/block/{block_content}/revision/{block_content_revision}/revert",
 *     "version-history" = "/admin/content/block/{block_content}/revisions",
 *   },
 *   translatable = TRUE,
 *   entity_keys = {
 *     "id" = "id",
 *     "revision" = "revision_id",
 *     "bundle" = "type",
 *     "label" = "info",
 *     "langcode" = "langcode",
 *     "uuid" = "uuid",
 *     "published" = "status",
 *   },
 *   revision_metadata_keys = {
 *     "revision_user" = "revision_user",
 *     "revision_created" = "revision_created",
 *     "revision_log_message" = "revision_log"
 *   },
 *   bundle_entity_type = "block_content_type",
 *   field_ui_base_route = "entity.block_content_type.edit_form",
 *   render_cache = FALSE,
 * )
 *
 * Note that render caching of block_content entities is disabled because they
 * are always rendered as blocks, and blocks already have their own render
 * caching.
 * See https://www.drupal.org/node/2284917#comment-9132521 for more information.
 */
class BlockContent extends EditorialContentEntityBase implements BlockContentInterface {

  use RefinableDependentAccessTrait;

  /**
   * The theme the block is being created in.
   *
   * When creating a new content block from the block library, the user is
   * redirected to the configure form for that block in the given theme. The
   * theme is stored against the block when the content block add form is shown.
   *
   * @var string
   */
  protected $theme;

  /**
   * {@inheritdoc}
   */
  public function createDuplicate() {
    $duplicate = parent::createDuplicate();
    $duplicate->revision_id->value = NULL;
    $duplicate->id->value = NULL;
    return $duplicate;
  }

  /**
   * {@inheritdoc}
   */
  public function setTheme($theme) {
    $this->theme = $theme;
    return $this;
  }

  /**
   * {@inheritdoc}
   */
  public function getTheme() {
    return $this->theme;
  }

  /**
   * {@inheritdoc}
   */
  public function postSave(EntityStorageInterface $storage, $update = TRUE) {
    parent::postSave($storage, $update);
    if ($this->isReusable() || (isset($this->original) && $this->original->isReusable())) {
      static::invalidateBlockPluginCache();
    }
  }

  /**
   * {@inheritdoc}
   */
  public static function preDelete(EntityStorageInterface $storage, array $entities) {
    parent::preDelete($storage, $entities);

    /** @var \Drupal\block_content\BlockContentInterface $block */
    foreach ($entities as $block) {
      foreach ($block->getInstances() as $instance) {
        $instance->delete();
      }
    }
  }

  /**
   * {@inheritdoc}
   */
  public static function postDelete(EntityStorageInterface $storage, array $entities) {
    parent::postDelete($storage, $entities);
    /** @var \Drupal\block_content\BlockContentInterface $block */
    foreach ($entities as $block) {
      if ($block->isReusable()) {
        // If any deleted blocks are reusable clear the block cache.
        static::invalidateBlockPluginCache();
        return;
      }
    }
  }

  /**
   * {@inheritdoc}
   */
  public function getInstances() {
    return \Drupal::entityTypeManager()->getStorage('block')->loadByProperties(['plugin' => 'block_content:' . $this->uuid()]);
  }

  /**
   * {@inheritdoc}
   */
  public function preSaveRevision(EntityStorageInterface $storage, \stdClass $record) {
    parent::preSaveRevision($storage, $record);

    if (!$this->isNewRevision() && isset($this->original) && empty($record->revision_log_message)) {
      // If we are updating an existing block_content without adding a new
      // revision and the user did not supply a revision log, keep the existing
      // one.
      $record->revision_log = $this->original->getRevisionLogMessage();
    }
  }

  /**
   * {@inheritdoc}
   */
  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
    /** @var \Drupal\Core\Field\BaseFieldDefinition[] $fields */
    $fields = parent::baseFieldDefinitions($entity_type);

    $fields['id']->setLabel(t('Content block ID'))
      ->setDescription(t('The content block ID.'));

    $fields['uuid']->setDescription(t('The content block UUID.'));

    $fields['revision_id']->setDescription(t('The revision ID.'));

    $fields['langcode']->setDescription(t('The content block language code.'));

    $fields['type']->setLabel(t('Block type'))
      ->setDescription(t('The block type.'));

    $fields['revision_log']->setDescription(t('The log entry explaining the changes in this revision.'));

    $fields['info'] = BaseFieldDefinition::create('string')
      ->setLabel(t('Block description'))
      ->setDescription(t('A brief description of your block.'))
      ->setRevisionable(TRUE)
      ->setTranslatable(TRUE)
      ->setRequired(TRUE)
      ->setDisplayOptions('form', [
        'type' => 'string_textfield',
        'weight' => -5,
      ])
      ->setDisplayConfigurable('form', TRUE);

    $fields['changed'] = BaseFieldDefinition::create('changed')
      ->setLabel(t('Changed'))
      ->setDescription(t('The time that the content block was last edited.'))
      ->setTranslatable(TRUE)
      ->setRevisionable(TRUE);

    $fields['reusable'] = BaseFieldDefinition::create('boolean')
      ->setLabel(t('Reusable'))
      ->setDescription(t('A boolean indicating whether this block is reusable.'))
      ->setTranslatable(FALSE)
      ->setRevisionable(FALSE)
      ->setDefaultValue(TRUE);

    return $fields;
  }

  /**
   * {@inheritdoc}
   */
  public function setInfo($info) {
    $this->set('info', $info);
    return $this;
  }

  /**
   * {@inheritdoc}
   */
  public function isReusable() {
    return (bool) $this->get('reusable')->value;
  }

  /**
   * {@inheritdoc}
   */
  public function setReusable() {
    return $this->set('reusable', TRUE);
  }

  /**
   * {@inheritdoc}
   */
  public function setNonReusable() {
    return $this->set('reusable', FALSE);
  }

  /**
   * Invalidates the block plugin cache after changes and deletions.
   */
  protected static function invalidateBlockPluginCache() {
    // Invalidate the block cache to update content block-based derivatives.
    \Drupal::service('plugin.manager.block')->clearCachedDefinitions();
  }

}