pattern_library-8.x-2.x-dev/pattern_library.module

<?php

/**
 * @file
 * The hook implementations for the pattern library module.
 */

use Drupal\Core\Render\Element;
use Drupal\Core\Template\Attribute;
use Drupal\pattern_library\PatternLibraryManager;
use Drupal\pattern_library\Plugin\Pattern;

/**
 * Implements hook_theme().
 */
function pattern_library_theme($existing, $type, $theme, $path) {
  return [
    'pattern_library_layout' => [
      'render element' => 'content',
    ]
  ];
}

/**
 * Implements hook_library_info_build().
 */
function pattern_library_library_info_build() {
  /** @var PatternLibraryManager $manager */
  $manager = \Drupal::service('plugin.manager.pattern_library');

  $libraries =  [];
  /** @var Pattern $instance */
  foreach ($manager->getDefinitionInstances() as $plugin_id => $instance) {
    if (!$instance->hasLibraries()) {
      continue;
    }
    $libraries[$instance->libraryKey()] = $instance->getLibraries();
  }

  return $libraries;
}

/**
 * Template preprocess for pattern library layout.
 *
 * @param $variables
 *   An array of the template variables.
 */
function template_preprocess_pattern_library_layout(&$variables) {
  $variables['source'] = isset($variables['content']['#source'])
    ? $variables['content']['#source']
    : NULL;

  $variables['layout'] = isset($variables['content']['#layout'])
    ? $variables['content']['#layout']
    : [];

  foreach (Element::children($variables['content']) as $name) {
    if (!isset($variables['content'][$name]['#attributes'])) {
      $variables['content'][$name]['#attributes'] = [];
    }
    $variables['region_attributes'][$name] = new Attribute($variables['content'][$name]['#attributes']);
  }

  $variables['source_args'] = pattern_library_extract_layout_arguments($variables);
}

/**
 * Pattern library extract layout arguments.
 *
 * @param array $variables
 *   An array of template variables.
 *
 * @return array
 *   An array of layout arguments.
 */
function pattern_library_extract_layout_arguments(array $variables) {
  $arguments = array_intersect_key(
    $variables['content'],
    array_flip(Element::children($variables['content']))
  );

  // Modifiers are unique to the pattern library module and provides a seamless
  // way to pass modifiers to the pattern library patterns.
  $arguments['modifiers'] = isset($variables['content']['#modifiers'])
    ? $variables['content']['#modifiers']
    : [];

  // Attributes aren't truly needed, but emulsify will thrown an error when
  // using the bem() function without the attributes in the context.
  $arguments['attributes'] = new Attribute($variables['attributes']);

  // This is required to allow layout blocks to be dragged and dropped between
  // the regions within the layout builder interface.
  $arguments['region_attributes'] = $variables['region_attributes'];

  return $arguments;
}