<?php

/**
 * @file
 */

use Drupal\Core\Form\FormStateInterface;
use Drupal\menu_link_content\Entity\MenuLinkContent;
use Drupal\node\NodeTypeInterface;
use Drupal\node\NodeInterface;

/**
 * Helper function to create or update a menu link for a node.
 *
 * @param \Drupal\node\NodeInterface $node
 *   Node entity.
 * @param array $values
 *   Values for the menu link.
 */
function _menu_ui_node_save(NodeInterface $node, array $values): void {
  /** @var \Drupal\menu_link_content\MenuLinkContentInterface $entity */
  if (!empty($values['entity_id'])) {
    $entity = \Drupal::service('entity.repository')->getActive('menu_link_content', $values['entity_id']);
    if ($entity->isTranslatable() && $node->isTranslatable()) {
      if (!$entity->hasTranslation($node->language()->getId())) {
        $entity = $entity->addTranslation($node->language()->getId(), $entity->toArray());
      }
      else {
        $entity = $entity->getTranslation($node->language()->getId());
      }
    }
    else {
      // Ensure the entity matches the node language.
      $entity = $entity->getUntranslated();
      $entity->set($entity->getEntityType()->getKey('langcode'), $node->language()->getId());
    }
  }
  else {
    // Create a new menu_link_content entity.
    $entity = MenuLinkContent::create([
      'link' => ['uri' => 'entity:node/' . $node->id()],
      'langcode' => $node->language()->getId(),
    ]);
    $entity->enabled->value = 1;
  }
  $entity->title->value = trim($values['title']);
  $entity->description->value = trim($values['description']);
  $entity->menu_name->value = $values['menu_name'];
  $entity->parent->value = $values['parent'];
  $entity->weight->value = $values['weight'] ?? 0;
  if ($entity->isNew()) {
    // @todo The menu link doesn't need to be changed in a workspace context.
    //   Fix this in https://www.drupal.org/project/drupal/issues/3511204.
    if (!$node->isDefaultRevision() && $node->hasLinkTemplate('latest-version')) {
      // If a new menu link is created while saving the node as a pending draft
      // (non-default revision), store it as a link to the latest version.
      // That ensures that there is a regular, valid link target that is
      // only visible to users with permission to view the latest version.
      $entity->get('link')->uri = 'internal:/node/' . $node->id() . '/latest';
    }
  }
  else {
    $entity->isDefaultRevision($node->isDefaultRevision());
    if (!$entity->isDefaultRevision()) {
      $entity->setNewRevision(TRUE);
    }
    elseif ($entity->get('link')->uri !== 'entity:node/' . $node->id()) {
      $entity->get('link')->uri = 'entity:node/' . $node->id();
    }
  }
  $entity->save();
}

/**
 * Returns the definition for a menu link for the given node.
 *
 * @param \Drupal\node\NodeInterface $node
 *   The node entity.
 *
 * @return array
 *   An array that contains default values for the menu link form.
 */
function menu_ui_get_menu_link_defaults(NodeInterface $node) {
  // Prepare the definition for the edit form.
  /** @var \Drupal\node\NodeTypeInterface $node_type */
  $node_type = $node->type->entity;
  $menu_name = strtok($node_type->getThirdPartySetting('menu_ui', 'parent', 'main:'), ':');
  $defaults = FALSE;
  if ($node->id()) {
    $id = FALSE;
    // Give priority to the default menu.
    $type_menus = $node_type->getThirdPartySetting('menu_ui', 'available_menus', ['main']);
    // An existing menu link either points to the canonical or the latest path,
    // in case of a new menu link that was creating while saving as a pending
    // draft.
    $uri_candidates = ['entity:node/' . $node->id(), 'internal:/node/' . $node->id() . '/latest'];

    if (in_array($menu_name, $type_menus)) {
      $query = \Drupal::entityQuery('menu_link_content')
        ->accessCheck(TRUE)
        ->condition('link.uri', $uri_candidates, 'IN')
        ->condition('menu_name', $menu_name)
        ->sort('id', 'ASC')
        ->range(0, 1);
      $result = $query->execute();

      $id = (!empty($result)) ? reset($result) : FALSE;
    }
    // Check all allowed menus if a link does not exist in the default menu.
    if (!$id && !empty($type_menus)) {
      $query = \Drupal::entityQuery('menu_link_content')
        ->accessCheck(TRUE)
        ->condition('link.uri', $uri_candidates, 'IN')
        ->condition('menu_name', array_values($type_menus), 'IN')
        ->sort('id', 'ASC')
        ->range(0, 1);
      $result = $query->execute();

      $id = (!empty($result)) ? reset($result) : FALSE;
    }
    if ($id) {
      $menu_link = \Drupal::service('entity.repository')->getActive('menu_link_content', $id);
      $defaults = [
        'entity_id' => $menu_link->id(),
        'id' => $menu_link->getPluginId(),
        'title' => $menu_link->getTitle(),
        'title_max_length' => $menu_link->getFieldDefinitions()['title']->getSetting('max_length'),
        'description' => $menu_link->getDescription(),
        'description_max_length' => $menu_link->getFieldDefinitions()['description']->getSetting('max_length'),
        'menu_name' => $menu_link->getMenuName(),
        'parent' => $menu_link->getParentId(),
        'weight' => $menu_link->getWeight(),
      ];
    }
  }

  if (!$defaults) {
    // Get the default max_length of a menu link title from the base field
    // definition.
    $field_definitions = \Drupal::service('entity_field.manager')->getBaseFieldDefinitions('menu_link_content');
    $max_length = $field_definitions['title']->getSetting('max_length');
    $description_max_length = $field_definitions['description']->getSetting('max_length');
    $defaults = [
      'entity_id' => 0,
      'id' => '',
      'title' => '',
      'title_max_length' => $max_length,
      'description' => '',
      'description_max_length' => $description_max_length,
      'menu_name' => $menu_name,
      'parent' => '',
      'weight' => 0,
    ];
  }
  return $defaults;
}

/**
 * Entity form builder to add the menu information to the node.
 */
function menu_ui_node_builder($entity_type, NodeInterface $entity, &$form, FormStateInterface $form_state): void {
  $entity->menu = $form_state->getValue('menu');
}

/**
 * Form submission handler for menu item field on the node form.
 *
 * @see menu_ui_form_node_form_alter()
 */
function menu_ui_form_node_form_submit($form, FormStateInterface $form_state): void {
  $node = $form_state->getFormObject()->getEntity();
  if (!$form_state->isValueEmpty('menu')) {
    $values = $form_state->getValue('menu');
    if (empty($values['enabled'])) {
      if ($values['entity_id']) {
        $entity = \Drupal::service('entity.repository')->getActive('menu_link_content', $values['entity_id']);
        $entity->delete();
      }
    }
    else {
      // In case the menu title was left empty, fall back to the node title.
      if (empty(trim($values['title']))) {
        $values['title'] = $node->label();
      }
      // Decompose the selected menu parent option into 'menu_name' and
      // 'parent', if the form used the default parent selection widget.
      if (!empty($values['menu_parent'])) {
        [$menu_name, $parent] = explode(':', $values['menu_parent'], 2);
        $values['menu_name'] = $menu_name;
        $values['parent'] = $parent;
      }
      _menu_ui_node_save($node, $values);
    }
  }
}

/**
 * Validate handler for forms with menu options.
 *
 * @see menu_ui_form_node_type_form_alter()
 */
function menu_ui_form_node_type_form_validate(&$form, FormStateInterface $form_state): void {
  $available_menus = array_filter($form_state->getValue('menu_options'));
  // If there is at least one menu allowed, the selected item should be in
  // one of them.
  if (count($available_menus)) {
    $menu_item_id_parts = explode(':', $form_state->getValue('menu_parent'));
    if (!in_array($menu_item_id_parts[0], $available_menus)) {
      $form_state->setErrorByName('menu_parent', t('The selected menu link is not under one of the selected menus.'));
    }
  }
  else {
    $form_state->setValue('menu_parent', '');
  }
}

/**
 * Entity builder for the node type form with menu options.
 *
 * @see menu_ui_form_node_type_form_alter()
 */
function menu_ui_form_node_type_form_builder($entity_type, NodeTypeInterface $type, &$form, FormStateInterface $form_state): void {
  $type->setThirdPartySetting('menu_ui', 'available_menus', array_values(array_filter($form_state->getValue('menu_options'))));
  $type->setThirdPartySetting('menu_ui', 'parent', $form_state->getValue('menu_parent'));
}

/**
 * Implements hook_preprocess_HOOK() for block templates.
 */
function menu_ui_preprocess_block(&$variables): void {
  if ($variables['configuration']['provider'] == 'menu_ui') {
    $variables['attributes']['role'] = 'navigation';
  }
}