editor_button_link.module in Editor Button Link 8

Button link styles.

File

editor_button_link.module

<?php

/**
 * @file
 * Button link styles.
 */
use Drupal\Core\Form\FormStateInterface;
use Drupal\editor\Entity\Editor;

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * Note: the editor_file module declares that its EditorFileDialog form uses
 *   'editor_link_dialog' as base_form_id. In this case, the function above is
 *   going to be called as an implementation of hook_form_BASE_FORM_ID_alter().
 */
function editor_button_link_form_editor_link_dialog_alter(&$form, FormStateInterface $form_state, $form_id) {
  $argument = $form_state
    ->getBuildInfo()['args'][0];

  // In case the only argument we get is the Editor instead of the FilterFormat.
  if ($argument instanceof Editor) {
    $argument = $argument
      ->getFilterFormat();
  }
  $restrictions = $argument
    ->getHtmlRestrictions();
  if (isset($form_state
    ->getUserInput()['editor_object'])) {
    $input = $form_state
      ->getUserInput()['editor_object'];
    $form_state
      ->set('link_element', $input);
    $form_state
      ->setCached(TRUE);
  }
  else {

    // Retrieve the link element's attributes from form state.
    $input = $form_state
      ->get('link_element') ?: [];
  }

  /*
   * Helper to retrieve form fields' default values.
   *
   * @param string $attribute_name
   * @param string $fallback
   *
   * @return mixed
   *   The existing value or the fallback.
   */
  $get_default_value = function ($attribute_name, $fallback = '') use ($input) {
    return !empty($input[$attribute_name]) ? $input[$attribute_name] : $fallback;
  };

  /*
   * Helper to set the status of a form field according to the status of the
   * filter about the attribute it is defining.
   *
   * @param string $attribute_name
   *
   * @return bool
   *   TRUE if the filter is disabled or if the entire "a" tag is allowed or if
   *   the given attribute is allowed for the "a" tag.
   */
  $is_accessible = function ($attribute_name) use ($restrictions) {
    return $restrictions === FALSE || $restrictions['allowed']['a'] === TRUE || !empty($restrictions['allowed']['a'][$attribute_name]);
  };

  /** @var Drupal\filter\Entity\FilterFormat $filter_format */
  $filter_format = $form_state
    ->getBuildInfo()['args'][0];
  $plugin_format_filters = $filter_format
    ->id();
  $filter_config = \Drupal::config('filter.format.' . $plugin_format_filters);
  $filter_settings = $filter_config
    ->get('filters.editor_button_link_filter.settings');
  if (generate_option_settings($filter_settings['button_link_options'])) {
    $form['attributes']['data-drupal-button-link'] = [
      '#type' => 'select',
      '#title' => t('Button'),
      '#description' => t('Transform link style to a button'),
      '#options' => generate_option_settings($filter_settings['button_link_options']),
      '#default_value' => $get_default_value('data-drupal-button-link'),
      '#access' => $is_accessible('class'),
      '#weight' => 3,
    ];
  }
  if (generate_option_settings($filter_settings['button_link_size_options'])) {
    $form['attributes']['data-drupal-button-link-size'] = [
      '#type' => 'select',
      '#title' => t('Button size'),
      '#description' => t('Transform link style to a button'),
      '#options' => generate_option_settings($filter_settings['button_link_size_options']),
      '#default_value' => $get_default_value('data-drupal-button-link-size'),
      '#access' => $is_accessible('class'),
      '#group' => 'buttonlink',
      '#states' => [
        'invisible' => [
          'select[name="attributes[data-drupal-button-link]"]' => [
            'value' => '',
          ],
        ],
      ],
      '#weight' => 21,
    ];
  }
  if (generate_option_settings($filter_settings['button_link_style_options'])) {
    $form['attributes']['data-drupal-button-link-style'] = [
      '#type' => 'select',
      '#title' => t('Button style'),
      '#description' => t('Transform link style to a button'),
      '#options' => generate_option_settings($filter_settings['button_link_style_options']),
      '#default_value' => $get_default_value('data-drupal-button-link-style'),
      '#access' => $is_accessible('class'),
      '#group' => 'buttonlink',
      '#states' => [
        'invisible' => [
          'select[name="attributes[data-drupal-button-link]"]' => [
            'value' => '',
          ],
        ],
      ],
      '#weight' => 21,
    ];
  }

  // Add #validate callback that handles empty attributes.
  array_unshift($form['#validate'], '_editor_button_link_attributes_validate');
}

/**
 * Filter empty attributes to avoid empty HTML output.
 */
function _editor_button_link_attributes_validate(array &$form, FormStateInterface $form_state) {
  $values = $form_state
    ->getValue('attributes');
  $link_element = $form_state
    ->get('link_element');
  foreach ($values as $key => $value) {
    if (empty($value)) {
      $form_state
        ->setValue([
        'attributes',
        $key,
      ], '');

      // Special case on content creation.
      if (empty($link_element)) {
        $form_state
          ->unsetValue([
          'attributes',
          $key,
        ]);
      }
    }
  }
}

/**
 * Builds the "optionSets" configuration part.
 */
function generate_option_settings($options) {
  $options_set = [];

  // Early-return when empty.
  $options = trim($options);
  if (empty($options)) {
    return $options_set;
  }
  $options = str_replace([
    "\r\n",
    "\r",
  ], "\n", $options);
  foreach (explode("\n", $options) as $option) {
    $option = trim($option);

    // Ignore empty lines in between non-empty lines.
    if (empty($option)) {
      continue;
    }

    // Parse.
    list($selector, $label) = explode('|', $option);
    $options_set[trim($selector)] = trim($label);
  }
  return $options_set;
}

Functions

Name	Description
editor_button_link_form_editor_link_dialog_alter	Implements hook_form_FORM_ID_alter().
generate_option_settings	Builds the "optionSets" configuration part.
_editor_button_link_attributes_validate	Filter empty attributes to avoid empty HTML output.