<?php

/**
 * @file
 */

use Drupal\Core\Access\AccessResult;
use Drupal\Core\Entity\ContentEntityInterface;
use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Language\LanguageInterface;

/**
 * Installs Content Translation's fields for a given entity type.
 *
 * @param string $entity_type_id
 *   The entity type ID.
 *
 * @todo Generalize this code in https://www.drupal.org/node/2346013.
 */
function _content_translation_install_field_storage_definitions($entity_type_id): void {
  /** @var \Drupal\Core\Entity\EntityFieldManagerInterface $field_manager */
  $field_manager = \Drupal::service('entity_field.manager');
  /** @var \Drupal\Core\Entity\EntityLastInstalledSchemaRepositoryInterface $schema_repository */
  $schema_repository = \Drupal::service('entity.last_installed_schema.repository');
  $definition_update_manager = \Drupal::entityDefinitionUpdateManager();

  $field_manager->useCaches(FALSE);
  $storage_definitions = $field_manager->getFieldStorageDefinitions($entity_type_id);
  $field_manager->useCaches(TRUE);
  $installed_storage_definitions = $schema_repository->getLastInstalledFieldStorageDefinitions($entity_type_id);
  foreach (array_diff_key($storage_definitions, $installed_storage_definitions) as $storage_definition) {
    /** @var \Drupal\Core\Field\FieldStorageDefinitionInterface $storage_definition */
    if ($storage_definition->getProvider() == 'content_translation') {
      $definition_update_manager->installFieldStorageDefinition($storage_definition->getName(), $entity_type_id, 'content_translation', $storage_definition);
    }
  }
}

/**
 * Access callback for the translation overview page.
 *
 * @param \Drupal\Core\Entity\EntityInterface $entity
 *   The entity whose translation overview should be displayed.
 *
 * @return \Drupal\Core\Access\AccessResultInterface
 *   The access result.
 */
function content_translation_translate_access(EntityInterface $entity) {
  $account = \Drupal::currentUser();
  $condition = $entity instanceof ContentEntityInterface && $entity->access('view') &&
    !$entity->getUntranslated()->language()->isLocked() && \Drupal::languageManager()->isMultilingual() && $entity->isTranslatable() &&
    ($account->hasPermission('create content translations') || $account->hasPermission('update content translations') || $account->hasPermission('delete content translations') ||
    ($account->hasPermission('translate editable entities') && $entity->access('update')));
  return AccessResult::allowedIf($condition)->cachePerPermissions()->addCacheableDependency($entity);
}

/**
 * Returns a widget to enable content translation per entity bundle.
 *
 * Backward compatibility layer to support entities not using the language
 * configuration form element.
 *
 * @todo Remove once all core entities have language configuration.
 *
 * @param string $entity_type
 *   The type of the entity being configured for translation.
 * @param string $bundle
 *   The bundle of the entity being configured for translation.
 * @param array $form
 *   The configuration form array.
 * @param \Drupal\Core\Form\FormStateInterface $form_state
 *   The current state of the form.
 */
function content_translation_enable_widget($entity_type, $bundle, array &$form, FormStateInterface $form_state) {
  $key = $form_state->get(['content_translation', 'key']);
  $context = $form_state->get(['language', $key]) ?: [];
  $context += ['entity_type' => $entity_type, 'bundle' => $bundle];
  $form_state->set(['language', $key], $context);
  $element = content_translation_language_configuration_element_process(['#name' => $key], $form_state, $form);
  unset($element['content_translation']['#element_validate']);
  return $element;
}

/**
 * Process callback: Expands the language_configuration form element.
 *
 * @param array $element
 *   Form API element.
 *
 * @return array
 *   Processed language configuration element.
 */
function content_translation_language_configuration_element_process(array $element, FormStateInterface $form_state, array &$form) {
  if (empty($element['#content_translation_skip_alter']) && \Drupal::currentUser()->hasPermission('administer content translation')) {
    $key = $element['#name'];
    $form_state->set(['content_translation', 'key'], $key);
    $context = $form_state->get(['language', $key]);

    $element['content_translation'] = [
      '#type' => 'checkbox',
      '#title' => t('Enable translation'),
      // For new bundle, we don't know the bundle name yet,
      // default to no translatability.
      '#default_value' => $context['bundle'] ? \Drupal::service('content_translation.manager')->isEnabled($context['entity_type'], $context['bundle']) : FALSE,
      '#element_validate' => ['content_translation_language_configuration_element_validate'],
    ];

    $submit_name = isset($form['actions']['save_continue']) ? 'save_continue' : 'submit';
    // Only add the submit handler on the submit button if the #submit property
    // is already available, otherwise this breaks the form submit function.
    if (isset($form['actions'][$submit_name]['#submit'])) {
      $form['actions'][$submit_name]['#submit'][] = 'content_translation_language_configuration_element_submit';
    }
    else {
      $form['#submit'][] = 'content_translation_language_configuration_element_submit';
    }
  }
  return $element;
}

/**
 * Form validation handler for the language_configuration form element.
 *
 * Checks whether translation can be enabled: if language is set to one of the
 * special languages and language selector is not hidden, translation cannot be
 * enabled.
 *
 * @see content_translation_language_configuration_element_submit()
 */
function content_translation_language_configuration_element_validate($element, FormStateInterface $form_state, array $form): void {
  $key = $form_state->get(['content_translation', 'key']);
  $values = $form_state->getValue($key);
  if (!$values['language_alterable'] && $values['content_translation'] && \Drupal::languageManager()->isLanguageLocked($values['langcode'])) {
    foreach (\Drupal::languageManager()->getLanguages(LanguageInterface::STATE_LOCKED) as $language) {
      $locked_languages[$language->getId()] = $language->getName();
    }
    // @todo Set the correct form element name as soon as the element parents
    //   are correctly set. We should be using NestedArray::getValue() but for
    //   now we cannot.
    $form_state->setErrorByName('', t('"Show language selector" is not compatible with translating content that has default language: %choice. Either do not hide the language selector or pick a specific language.', ['%choice' => $locked_languages[$values['langcode']]]));
  }
}

/**
 * Form submission handler for element.
 *
 * Stores the content translation settings.
 *
 * @see content_translation_language_configuration_element_validate()
 */
function content_translation_language_configuration_element_submit(array $form, FormStateInterface $form_state): void {
  $key = $form_state->get(['content_translation', 'key']);
  $context = $form_state->get(['language', $key]);
  $enabled = $form_state->getValue([$key, 'content_translation']);

  if (\Drupal::service('content_translation.manager')->isEnabled($context['entity_type'], $context['bundle']) != $enabled) {
    \Drupal::service('content_translation.manager')->setEnabled($context['entity_type'], $context['bundle'], $enabled);
    \Drupal::service('router.builder')->setRebuildNeeded();
  }
}

/**
 * Implements hook_preprocess_HOOK() for language-content-settings-table.html.twig.
 */
function content_translation_preprocess_language_content_settings_table(&$variables): void {
  \Drupal::moduleHandler()->loadInclude('content_translation', 'inc', 'content_translation.admin');
  _content_translation_preprocess_language_content_settings_table($variables);
}