picture_everywhere-1.0.0/src/Preprocess.php

<?php

namespace Drupal\picture_everywhere;

use Drupal\Core\Template\Attribute;

/**
 * Preprocessing functionality for Picture Everywhere.
 */
class Preprocess {

  /**
   * A list of HTML attributes that should always go on the <img> element.
   *
   * @var string[]
   */
  public const ALWAYS_IMG_TAG_ATTRS = [
    'alt',
    'crossorigin',
    'decoding',
    'height',
    'loading',
    'referrerpolicy',
    'src',
    'srcset',
    'sizes',
    'width',
  ];

  /**
   * Implements hook_preprocess_image().
   */
  public static function preprocessImage(array &$variables): void {
    if (!empty($variables['in_picture'])) {
      return;
    }

    // We want to pull up all attributes passed to the filter to the <picture>
    // element.
    $variables['picture_attributes'] = static::splitAttributes($variables['attributes']);

    if (
      \Drupal::config('picture_everywhere.settings')->get('output.webp.auto_webp_source')
      && (
        !empty($variables['attributes']['src'])
        || !empty($variables['attributes']['srcset'])
      )
    ) {
      $original_src = !empty($variables['attributes']['srcset']) ?
        $variables['attributes']['srcset'] :
        $variables['attributes']['src'];
      $webp_src_value = explode('?', $original_src);
      $webp_src_value = preg_replace('/\.(jpe?g|png)$/i', '.webp', $webp_src_value, -1, $replacement_count);
      if ($replacement_count) {
        $webp_src_value = implode('?', $webp_src_value);
        $variables['sources']['attributes'] = new Attribute([
          'srcset' => $webp_src_value,
          'type' => 'image/webp',
        ]);
      }
    }
  }

  /**
   * Implements hook_preprocess_responsive_image().
   */
  public static function preprocessResponsiveImage(array &$variables): void {
    if (empty($variables['output_image_tag'])) {
      $variables['img_element']['#in_picture'] = TRUE;
    }
  }

  /**
   * Implements hook_preprocess_svg_image_field_formatter().
   */
  public static function preprocessSvgImageFieldFormatter(array &$variables): void {
    if (!empty($variables['inline'])) {
      return;
    }

    // We want to pull up all attributes passed to the filter to the <picture>
    // element.
    $variables['picture_attributes'] = static::splitAttributes($variables['attributes']);

    // SVG Image Field itself sets no loading attribute. We want to default to
    // lazy unless specified otherwise.
    if (!array_key_exists('loading', $variables['attributes'])) {
      $variables['attributes']['loading'] = 'lazy';
    }
  }

  /**
   * Get the names of HTML attributes that should be on the <img> tag.
   *
   * @return string[]
   *   The HTML attribute names that should be on the <img> tag instead of
   *   <picture>.
   */
  protected static function getImgTagAttributeNames(): array {
    $tags = &drupal_static(__METHOD__);
    if (!isset($tags)) {
      $configured_names = \Drupal::config('picture_everywhere.settings')->get('output.img_tag_attributes') ?: [];
      $tags = array_merge(static::ALWAYS_IMG_TAG_ATTRS, $configured_names);
    }
    return $tags;
  }

  /**
   * Splits <img> tag attributes into two for <picture>/<img> tags.
   *
   * The picture tag attributes will be returned. Attributes "moved" to picture
   * tag attributes will be unset on the passed attributes.
   *
   * @param array|null &$attributes
   *   The original attributes array.
   *
   * @return \Drupal\Core\Template\Attribute
   *   The <picture> tag attributes.
   */
  protected static function splitAttributes(Attribute|array|null &$attributes = NULL): Attribute {
    $picture_attributes = [];

    if ($attributes) {
      $img_attr_names = static::getImgTagAttributeNames();
      foreach (array_keys($attributes) as $attribute_name) {
        if (in_array($attribute_name, $img_attr_names, TRUE)) {
          continue;
        }
        $picture_attributes[$attribute_name] = $attributes[$attribute_name];
        unset($attributes[$attribute_name]);
      }
    }

    return new Attribute($picture_attributes);
  }

}