<?php

/**
 * @file
 * Domain-based path rewrites for content.
 */

use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Routing\TrustedRedirectResponse;
use Drupal\Core\Form\FormStateInterface;
use Drupal\domain\DomainRedirectResponse;

/**
 * Defines the name of the source domain field.
 */
const DOMAIN_SOURCE_FIELD = 'field_domain_source';

/**
 * Creates our fields for an entity bundle.
 *
 * @param string $entity_type
 *   The entity type being created. Node and user are supported.
 * @param string $bundle
 *   The bundle being created.
 *
 * @see domain_source_node_type_insert()
 * @see domain_source_install()
 */
function domain_source_confirm_fields($entity_type, $bundle) {
  $id = $entity_type . '.' . $bundle . '.' . DOMAIN_SOURCE_FIELD;
  $field_config_storage = \Drupal::entityTypeManager()->getStorage('field_config');

  if (!$field = $field_config_storage->load($id)) {
    $field = array(
      'field_name' => DOMAIN_SOURCE_FIELD,
      'entity_type' => $entity_type,
      'label' => 'Domain Source',
      'bundle' => $bundle,
      'required' => FALSE,
      'description' => 'Select the canonical domain for this content.',
      'settings' => array(
        'handler' => 'default:domain',
        // Handler_settings are deprecated but seem to be necessary here.
        'handler_settings' => [
          'target_bundles' => NULL,
          'sort' => ['field' => 'weight', 'direction' => 'ASC'],
        ],
        'target_bundles' => NULL,
        'sort' => ['field' => 'weight', 'direction' => 'ASC'],
      ),
    );
    $field_config = $field_config_storage->create($field);
    $field_config->save();
  }

  // Tell the form system how to behave. Default to radio buttons.
  if ($display = \Drupal::entityTypeManager()->getStorage('entity_form_display')->load($entity_type . '.' .  $bundle . '.default')) {
    $display->setComponent(DOMAIN_SOURCE_FIELD, [
      'type' => 'options_select',
      'weight' => 42,
    ])->save();
  }
}

/**
 * Implements hook_ENTITY_TYPE_insert().
 *
 * Creates our fields when new node types are created.
 *
 * @TODO: Make this possible for all entity types.
 */
function domain_source_node_type_insert(EntityInterface $entity) {
  /** @var \Drupal\Core\Config\Entity\ConfigEntityInterface $entity */
  if (!$entity->isSyncing()) {
    // Do not fire hook when config sync in progress.
    domain_source_confirm_fields('node', $entity->id());
  }
}

/**
 * Returns the source domain associated to an entity.
 *
 * @param Drupal\Core\Entity\EntityInterface $entity
 *   The entity to check.
 *
 * @return string|NULL
 *   The value assigned to the entity, either a domain id string or NULL.
 */
function domain_source_get(EntityInterface $entity) {
  $source = NULL;

  if (!isset($entity->{DOMAIN_SOURCE_FIELD})) {
    return $source;
  }

  $value = $entity->get(DOMAIN_SOURCE_FIELD)->offsetGet(0);
  if (!empty($value)) {
    $target_id = $value->target_id;
    if ($domain = \Drupal::service('entity_type.manager')->getStorage('domain')->load($target_id)) {
      $source = $domain->id();
    }
  }
  return $source;
}

/**
 * Implements hook_form_alter().
 *
 * Find forms that contain the domain source field and allow those to handle
 * redirects properly.
 */
function domain_source_form_alter(&$form, &$form_state, $form_id) {
  $object = $form_state->getFormObject();
  // Set up our TrustedRedirect handler for form saves.
  if (isset($form[DOMAIN_SOURCE_FIELD]) && !empty($object) && is_callable([$object, 'getEntity']) && $entity = $object->getEntity()) {
    foreach ($form['actions'] as $key => $element) {
      // Redirect submit handlers, but not the preview button.
      if ($key != 'preview' && isset($element['#type']) && $element['#type'] == 'submit') {
        $form['actions'][$key]['#submit'][] = 'domain_source_form_submit';
      }
    }
  }
}

/**
 * Validate form submissions.
 */
function domain_source_form_validate($element, \Drupal\Core\Form\FormStateInterface $form_state) {
  $values = $form_state->getValues();
  // This is only run if Domain Access is present.
  if (isset($values[DOMAIN_SOURCE_FIELD]) && is_array($values[DOMAIN_SOURCE_FIELD]) && isset($values[DOMAIN_ACCESS_FIELD])) {
    $access_values = $values[DOMAIN_ACCESS_FIELD];
    $source_value = current($values[DOMAIN_SOURCE_FIELD]);
  }
  // If no value is selected, that's acceptable. Else run through a check.
  // Note that the _none selection returns as [FALSE].
  $source_set = empty($source_value);
  foreach ($access_values as $value) {
    // Core is inconsistent depending on the field order.
    // See https://www.drupal.org/project/domain/issues/2945771#comment-12493199
    if (is_array($value) && $value == $source_value) {
      $source_set = TRUE;
    }
    elseif (is_string($value) && !empty($source_value['target_id']) && $value == $source_value['target_id']) {
      $source_set = TRUE;
    }
  }
  if (!$source_set) {
    $form_state->setError($element, t('The source domain must be selected as a publishing option.'));
  }
}

/**
 * Redirect form submissions to other domains.
 */
function domain_source_form_submit(&$form, \Drupal\Core\Form\FormStateInterface $form_state) {
  // Ensure that we have saved an entity.
  if ($object = $form_state->getFormObject()) {
    $url = $object->getEntity()->url();
  }
  // Validate that the URL will be considered "external" by Drupal, which means
  // that a scheme value will be present.
  if (!empty($url)) {
    $uri_parts = parse_url($url);
    // If necessary and secure, issue a TrustedRedirectResponse to the new URL.
    if (!empty($uri_parts['host'])) {
      // Pass a redirect if necessary.
      if (DomainRedirectResponse::checkTrustedHost($uri_parts['host'])) {
        $response = new TrustedRedirectResponse($url);
        $form_state->setResponse($response);
      }
    }
  }
}

/**
 * Implements hook_form_BASE_FORM_ID_alter() for \Drupal\node\NodeForm.
 */
function domain_source_form_node_form_alter(&$form, FormStateInterface $form_state, $form_id) {
  // Add the options hidden from the user silently to the form.
  $manager = \Drupal::service('domain_source.element_manager');
  $hide = TRUE;
  $form = $manager->setFormOptions($form, $form_state, DOMAIN_SOURCE_FIELD, $hide);
  // Add validation if Domain Access is installed.
  if (defined('DOMAIN_ACCESS_FIELD') && isset($form[DOMAIN_ACCESS_FIELD])) {
    $form[DOMAIN_SOURCE_FIELD]['#element_validate'] = array('domain_source_form_validate');
    // If using a select field, load the JS to show/hide options.
    if ($form[DOMAIN_SOURCE_FIELD]['widget']['#type'] == 'select') {
      $form['#attached']['library'][] = 'domain_source/drupal.domain_source';
    }
  }
}

/**
 * Implements hook_views_data_alter.
 */
function domain_source_views_data_alter(array &$data) {
  $table = 'node__' . DOMAIN_SOURCE_FIELD;
  $data[$table][DOMAIN_SOURCE_FIELD]['field']['id'] = 'domain_source';
  $data[$table][DOMAIN_SOURCE_FIELD . '_target_id']['filter']['id'] = 'domain_source';
  // Since domains are not stored in the database, relationships cannot be used.
  unset($data[$table][DOMAIN_SOURCE_FIELD]['relationship']);
}

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * Add options for domain source when using Devel Generate.
 */
function domain_source_form_devel_generate_form_content_alter(&$form, &$form_state, $form_id) {
  // Add our element to the Devel generate form.
  $list = ['_derive' => t('Derive from domain selection')];
  $list += \Drupal::service('entity_type.manager')->getStorage('domain')->loadOptionsList();
  $form['domain_source'] = array(
    '#title' => t('Domain source'),
    '#type' => 'checkboxes',
    '#options' => $list,
    '#weight' => 4,
    '#multiple' => TRUE,
    '#size' => count($list) > 5 ? 5 : count($list),
    '#default_value' => ['_derive'],
    '#description' => t('Sets the source domain for created nodes.'),
  );
}

/**
 * Implements hook_ENTITY_TYPE_presave().
 *
 * Fires only if Devel Generate module is present, to assign test nodes to
 * domains.
 */
function domain_source_node_presave(EntityInterface $node) {
  domain_source_presave_generate($node);
}

/**
 * Handles presave operations for devel generate.
 */
function domain_source_presave_generate(EntityInterface $entity) {
  // Handle devel module settings.
  $exists = \Drupal::moduleHandler()->moduleExists('devel_generate');
  $values = [];
  $selections = [];
  if ($exists && isset($entity->devel_generate)) {
    // If set by the form.
    if (isset($entity->devel_generate['domain_access'])) {
      $selection = array_filter($entity->devel_generate['domain_access']);
      if (isset($selection['random-selection'])) {
        $domains = \Drupal::service('entity_type.manager')->getStorage('domain')->loadMultiple();
        $selections = array_rand($domains, ceil(rand(1, count($domains))));
      }
      else {
        $selections = array_keys($selection);
      }
    }
    if (isset($entity->devel_generate['domain_source'])) {
      $selection = $entity->devel_generate['domain_source'];
      if ($selection == '_derive') {
        if (!empty($selections)) {
          $values[DOMAIN_SOURCE_FIELD] = current($selections);
        }
        else {
          $values[DOMAIN_SOURCE_FIELD] = NULL;
        }
      }
      foreach ($values as $name => $value) {
        $entity->set($name, $value);
      }
    }
  }
}