datafield-1.x-dev/src/Plugin/DataField/FieldFormatter/StringFormatter.php

<?php

namespace Drupal\datafield\Plugin\DataField\FieldFormatter;

use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Field\Attribute\FieldFormatter;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\StringTranslation\StringTranslationTrait;
use Drupal\Core\StringTranslation\TranslatableMarkup;
use Drupal\datafield\Plugin\DataFieldFormatterInterface;

/**
 * Plugin implementation of the 'string' formatter.
 */
#[FieldFormatter(
  id: 'string',
  label: new TranslatableMarkup('Plain text'),
  field_types: ['string', 'uri', 'email', 'json', 'serial'],
)]
class StringFormatter implements DataFieldFormatterInterface {

  use StringTranslationTrait;

  /**
   * {@inheritdoc}
   */
  public static function defaultSettings() {
    $options['link_to_entity'] = FALSE;
    return $options;
  }

  /**
   * {@inheritdoc}
   */
  public function settingsForm(array $form, FormStateInterface $form_state) {
    return [];
  }

  /**
   * {@inheritdoc}
   */
  public function settingsSummary($settings = []) {
    $summary = [];
    return $summary;
  }

  /**
   * {@inheritdoc}
   */
  public function viewElements($item, $langcode) {
    $url = NULL;
    $entity = $item->entity;
    if (empty($item->value)) {
      return $item->value;
    }
    $entity_type = $entity->getEntityType();

    if (!empty($item->settings['link_to_entity']) && !$entity->isNew() && $entity_type->hasLinkTemplate('canonical')) {
      $url = $this->getEntityUrl($entity);
    }
    $view_value = $this->viewValue($item->value);
    if ($url) {
      return [
        '#type' => 'link',
        '#title' => $view_value,
        '#url' => $url,
      ];
    }
    else {
      return $view_value;
    }
  }

  /**
   * {@inheritdoc}
   */
  protected function viewValue($value) {
    // The text value has no text format assigned to it, so the user input
    // should equal the output, including newlines.
    return [
      '#type' => 'inline_template',
      '#template' => '{{ value|nl2br }}',
      '#context' => ['value' => $value],
    ];
  }

  /**
   * Gets the URI elements of the entity.
   *
   * @param \Drupal\Core\Entity\EntityInterface $entity
   *   The entity object.
   *
   * @return \Drupal\Core\Url
   *   The URI elements of the entity.
   */
  protected function getEntityUrl(EntityInterface $entity) {
    // For the default revision, the 'revision' link template falls back to
    // 'canonical'.
    // @see \Drupal\Core\Entity\Entity::toUrl()
    $rel = $entity->getEntityType()->hasLinkTemplate('revision') ? 'revision' : 'canonical';
    return $entity->toUrl($rel);
  }

}