<?php

/**
 * @file
 */

use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Hook\Attribute\StopProceduralHookScan;
use Drupal\Core\Render\Element;
use Drupal\Core\Render\Element\RenderElementBase;
use Drupal\Core\Template\Attribute;
use Drupal\Core\Url;

/**
 * Prepares variables for media templates.
 *
 * Default template: media.html.twig.
 *
 * @param array $variables
 *   An associative array containing:
 *   - elements: An array of elements to display in view mode.
 *   - media: The media item.
 *   - name: The label for the media item.
 *   - view_mode: View mode; e.g., 'full', 'teaser', etc.
 */
#[StopProceduralHookScan]
function template_preprocess_media(array &$variables): void {
  $variables['media'] = $variables['elements']['#media'];
  $variables['view_mode'] = $variables['elements']['#view_mode'];
  $variables['name'] = $variables['media']->label();

  // Helpful $content variable for templates.
  foreach (Element::children($variables['elements']) as $key) {
    $variables['content'][$key] = $variables['elements'][$key];
  }
}

/**
 * Implements hook_preprocess_HOOK() for media reference widgets.
 */
function media_preprocess_media_reference_help(&$variables): void {
  // Most of these attribute checks are copied from
  // template_preprocess_fieldset(). Our template extends
  // field-multiple-value-form.html.twig to provide our help text, but also
  // groups the information within a semantic fieldset with a legend. So, we
  // incorporate parity for both.
  $element = $variables['element'];
  Element::setAttributes($element, ['id']);
  RenderElementBase::setAttributes($element);
  $variables['attributes'] = $element['#attributes'] ?? [];
  $variables['legend_attributes'] = new Attribute();
  $variables['header_attributes'] = new Attribute();
  $variables['description']['attributes'] = new Attribute();
  $variables['legend_span_attributes'] = new Attribute();

  if (!empty($element['#media_help'])) {
    foreach ($element['#media_help'] as $key => $text) {
      $variables[substr($key, 1)] = $text;
    }
  }
}

/**
 * Returns the appropriate URL to add media for the current user.
 *
 * @todo Remove in https://www.drupal.org/project/drupal/issues/2938116
 *
 * @param string[] $allowed_bundles
 *   An array of bundles that should be checked for create access.
 *
 * @return bool|\Drupal\Core\Url
 *   The URL to add media, or FALSE if the user cannot create any media.
 *
 * @internal
 *   This function is internal and may be removed in a minor release.
 */
function _media_get_add_url($allowed_bundles) {
  $access_handler = \Drupal::entityTypeManager()->getAccessControlHandler('media');
  $create_bundles = array_filter($allowed_bundles, [$access_handler, 'createAccess']);

  // Add a section about how to create media if the user has access to do so.
  if (count($create_bundles) === 1) {
    return Url::fromRoute('entity.media.add_form', ['media_type' => reset($create_bundles)])->toString();
  }
  elseif (count($create_bundles) > 1) {
    return Url::fromRoute('entity.media.add_page')->toString();
  }

  return FALSE;
}

/**
 * Validate callback to ensure filter order and allowed_html are compatible.
 */
function media_filter_format_edit_form_validate($form, FormStateInterface $form_state): void {
  if ($form_state->getTriggeringElement()['#name'] !== 'op') {
    return;
  }

  $allowed_html_path = [
    'filters',
    'filter_html',
    'settings',
    'allowed_html',
  ];

  $filter_html_settings_path = [
    'filters',
    'filter_html',
    'settings',
  ];

  $filter_html_enabled = $form_state->getValue([
    'filters',
    'filter_html',
    'status',
  ]);

  $media_embed_enabled = $form_state->getValue([
    'filters',
    'media_embed',
    'status',
  ]);

  if (!$media_embed_enabled) {
    return;
  }

  $get_filter_label = function ($filter_plugin_id) use ($form) {
    return (string) $form['filters']['order'][$filter_plugin_id]['filter']['#markup'];
  };

  if ($filter_html_enabled && $form_state->getValue($allowed_html_path)) {
    /** @var \Drupal\filter\Entity\FilterFormat $filter_format */
    $filter_format = $form_state->getFormObject()->getEntity();

    $filter_html = clone $filter_format->filters()->get('filter_html');
    $filter_html->setConfiguration(['settings' => $form_state->getValue($filter_html_settings_path)]);
    $restrictions = $filter_html->getHTMLRestrictions();
    $allowed = $restrictions['allowed'];

    // Require `<drupal-media>` HTML tag if filter_html is enabled.
    if (!isset($allowed['drupal-media'])) {
      $form_state->setError($form['filters']['settings']['filter_html']['allowed_html'], t('The %media-embed-filter-label filter requires <code>&lt;drupal-media&gt;</code> among the allowed HTML tags.', [
        '%media-embed-filter-label' => $get_filter_label('media_embed'),
      ]));
    }
    else {
      $required_attributes = [
        'data-entity-type',
        'data-entity-uuid',
      ];

      // If there are no attributes, the allowed item is set to FALSE,
      // otherwise, it is set to an array.
      if ($allowed['drupal-media'] === FALSE) {
        $missing_attributes = $required_attributes;
      }
      else {
        $missing_attributes = array_diff($required_attributes, array_keys($allowed['drupal-media']));
      }

      if ($missing_attributes) {
        $form_state->setError($form['filters']['settings']['filter_html']['allowed_html'], t('The <code>&lt;drupal-media&gt;</code> tag in the allowed HTML tags is missing the following attributes: <code>%list</code>.', [
          '%list' => implode(', ', $missing_attributes),
        ]));
      }
    }
  }

  $filters = $form_state->getValue('filters');

  // The "media_embed" filter must run after "filter_align", "filter_caption",
  // and "filter_html_image_secure".
  $precedents = [
    'filter_align',
    'filter_caption',
    'filter_html_image_secure',
  ];

  $error_filters = [];
  foreach ($precedents as $filter_name) {
    // A filter that should run before media embed filter.
    $precedent = $filters[$filter_name];

    if (empty($precedent['status']) || !isset($precedent['weight'])) {
      continue;
    }

    if ($precedent['weight'] >= $filters['media_embed']['weight']) {
      $error_filters[$filter_name] = $get_filter_label($filter_name);
    }
  }

  if (!empty($error_filters)) {
    $error_message = \Drupal::translation()->formatPlural(
      count($error_filters),
      'The %media-embed-filter-label filter needs to be placed after the %filter filter.',
      'The %media-embed-filter-label filter needs to be placed after the following filters: %filters.',
      [
        '%media-embed-filter-label' => $get_filter_label('media_embed'),
        '%filter' => reset($error_filters),
        '%filters' => implode(', ', $error_filters),
      ]
    );

    $form_state->setErrorByName('filters', $error_message);
  }
}