improvements-2.x-dev/modules/improvements_comment/improvements_comment.module

<?php

use Drupal\comment\CommentInterface;
use Drupal\comment\CommentTypeInterface;
use Drupal\Core\Entity\EntityTypeInterface;
use Drupal\Core\Field\BaseFieldDefinition;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Render\Markup;
use Drupal\Core\Url;
use Drupal\druhels\UserHelper;

/**
 * Implements hook_page_ROUTE_NAME_result_alter(): comment.reply.
 */
function improvements_comment_page_comment_reply_result_alter(array &$result): void {
  // Hide commented entity on comment form page
  if (isset($result['commented_entity'])) {
    $result['commented_entity']['#access'] = FALSE;
  }
}

/**
 * Implements hook_entity_base_field_info_alter().
 *
 * @param BaseFieldDefinition[] $fields
 *
 * @see improvements_entity_base_field_info_alter()
 */
function improvements_comment_entity_base_field_info_alter(array &$fields, EntityTypeInterface $entity_type): void {
  if ($entity_type->id() == 'comment') {
    // Add comment author and date on comment view display
    /** @see \Drupal\comment\Entity\Comment::baseFieldDefinitions() */
    $fields['uid']->setDisplayConfigurable('view', TRUE);
    $fields['name']->setDisplayConfigurable('view', TRUE)->setLabel(t('Author name'));
    $fields['mail']->setDisplayConfigurable('view', TRUE);
    $fields['created']->setDisplayConfigurable('view', TRUE);
    $fields['entity_id']->setDisplayConfigurable('view', TRUE)->setLabel(t('Commented entity'));

    $fields['created']->setLabel(t('Date of creation'));
    $fields['changed']->setLabel(t('Date of change'));
  }
}

/**
 * Implements hook_comment_links_alter().
 */
function improvements_comment_comment_links_alter(array &$links, CommentInterface $comment, array &$context): void {
  static $show_ban_link;

  if ($show_ban_link === NULL) {
    $show_ban_link = \Drupal::service('module_handler')->moduleExists('ban') && \Drupal::currentUser()->hasPermission('ban IP addresses');
  }

  if ($show_ban_link) {
    $links['comment']['#links']['comment-ban-author'] = [
      'title' => t('To ban'),
      'url' => Url::fromRoute('ban.admin_page', ['default_ip' => $comment->getHostname()], ['query' => \Drupal::destination()->getAsArray()]),
    ];
  }
}

/**
 * Implements hook_form_BASE_FORM_ID_alter(): comment_type_form.
 */
function improvements_comment_form_comment_type_form_alter(array &$form, FormStateInterface $form_state, string $form_id): void {
  $comment_type = $form_state->getFormObject()->getEntity(); /** @var CommentTypeInterface $comment_type */

  $form['new_comment_notify'] = [
    '#type' => 'checkbox',
    '#title' => t('Notify of new comments'),
    '#default_value' => $comment_type->getThirdPartySetting('improvements', 'new_comment_notify', FALSE),
  ];

  $form['new_comment_notify_email'] = [
    '#type' => 'textfield',
    '#title' => t('E-mail for notify'),
    '#description' => t('Support tokens.'),
    '#default_value' => $comment_type->getThirdPartySetting('improvements', 'new_comment_notify_email', '[site:mail]'),
    '#states' => [
      'visible' => [
        'input[name="new_comment_notify"]' => [
          'checked' => TRUE,
        ],
      ],
    ],
  ];

  $form['new_comment_notify_view_mode'] = [
    '#type' => 'select',
    '#title' => t('View mode for notify'),
    '#options' => \Drupal::service('entity_display.repository')->getViewModeOptions('comment'),
    '#default_value' => $comment_type->getThirdPartySetting('improvements', 'new_comment_notify_view_mode', 'default'),
    '#states' => $form['new_comment_notify_email']['#states'],
  ];

  $form['#entity_builders'][] = 'improvements_comment_form_comment_type_form_entity_builder';
}

/**
 * Custom submit callback for comment_type_form form.
 *
 * @see improvements_form_comment_type_form_alter()
 */
function improvements_comment_form_comment_type_form_entity_builder(string $comment_type_id, CommentTypeInterface $comment_type, array &$form, FormStateInterface $form_state): void {
  $comment_type->setThirdPartySetting('improvements', 'new_comment_notify', (bool)$form_state->getValue('new_comment_notify'));
  $comment_type->setThirdPartySetting('improvements', 'new_comment_notify_email', $form_state->getValue('new_comment_notify_email'));
  $comment_type->setThirdPartySetting('improvements', 'new_comment_notify_view_mode', $form_state->getValue('new_comment_notify_view_mode'));
}

/**
 * Implements hook_ENTITY_TYPE_insert(): comment.
 */
function improvements_comment_comment_insert(CommentInterface $comment): void {
  $comment_type = $comment->get('comment_type')->entity; /** @var CommentTypeInterface $comment_type */
  $comment_improvements_settings = $comment_type->getThirdPartySettings('improvements');

  if (
    !empty($comment_improvements_settings['new_comment_notify']) &&
    !empty($comment_improvements_settings['new_comment_notify_email'])
  ) {
    \Drupal::service('plugin.manager.mail')->mail(
      'improvements',
      'new_comment_notify',
      \Drupal::token()->replace($comment_improvements_settings['new_comment_notify_email']),
      \Drupal::languageManager()->getCurrentLanguage()->getId(),
      ['comment' => $comment]
    );
  }
}

/**
 * Implements hook_mail().
 */
function improvements_comment_mail(string $key, array &$message, array $params): void {
  if ($key == 'new_comment_notify') {
    $comment = $params['comment']; /** @var CommentInterface $comment */
    $comment_type = $comment->get('comment_type')->entity; /** @var CommentTypeInterface $comment_type */
    $comment_view_mode = $comment_type->getThirdPartySetting('improvements', 'new_comment_notify_view_mode', 'default');

    $message['subject'] = t('New comment on @site in "@label"', [
      '@site' => \Drupal::request()->getHost(),
      '@label' => $comment->getCommentedEntity()->label(),
    ]);

    $comment_build = \Drupal::entityTypeManager()->getViewBuilder('comment')->view($comment, $comment_view_mode);

    // Render as admin
    $account_switcher = \Drupal::service('account_switcher');
    $account_switcher->switchTo(UserHelper::getAdminUser());
    $message['body'][] = Markup::create(\Drupal::service('renderer')->renderPlain($comment_build));
    $account_switcher->switchBack();
  }
}