<?php

/**
 * @file
 * Allows administrators to attach custom fields to fieldable types.
 */

use Drupal\Component\Utility\Html;
use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Render\Element;
use Drupal\Core\Routing\RouteMatchInterface;
use Drupal\Core\Entity\EntityViewModeInterface;
use Drupal\field_ui\FieldUI;
use Drupal\field_ui\Plugin\Derivative\FieldUiLocalTask;

/**
 * Implements hook_help().
 */
function field_ui_help($route_name, RouteMatchInterface $route_match) {
  $module_handler = \Drupal::moduleHandler();

  switch ($route_name) {
    case 'help.page.field_ui':
      $output = '';
      $output .= '<h3>' . t('About') . '</h3>';
      $output .= '<p>' . t('The Field UI module provides an administrative user interface (UI) for attaching and managing fields. Fields can be defined at the content-type level for content items and comments, at the vocabulary level for taxonomy terms, and at the site level for user accounts. Other modules may also enable fields to be defined for their data. Field types (text, image, number, etc.) are defined by modules, and collected and managed by the <a href="@field">Field module</a>. For more information, see the online handbook entry for <a href="@field_ui" target="_blank">Field UI module</a>.', array('@field' => \Drupal::url('help.page', array('name' => 'field')), '@field_ui' => 'http://drupal.org/documentation/modules/field-ui')) . '</p>';
      $output .= '<h3>' . t('Uses') . '</h3>';
      $output .= '<dl>';
      $output .= '<dt>' . t('Planning fields') . '</dt>';
      $output .= '<dd>' . t('There are several decisions you will need to make before defining a field for content, comments, etc.:') . '<dl>';
      $output .= '<dt>' . t('What the field will be called') . '</dt>';
      $output .= '<dd>' . t('A field has a <em>label</em> (the name displayed in the user interface) and a <em>machine name</em> (the name used internally). The label can be changed after you create the field, if needed, but the machine name cannot be changed after you have created the field.') . '</li>';
      $output .= '<dt>' . t('What type of data the field will store') . '</dt>';
      $output .= '<dd>' . t('Each field can store one type of data (text, number, file, etc.). When you define a field, you choose a particular <em>field type</em>, which corresponds to the type of data you want to store. The field type cannot be changed after you have created the field.') . '</dd>';
      $output .= '<dt>' . t('How the data will be input and displayed') . '</dt>';
      $output .= '<dd>' . t('Each field type has one or more available <em>widgets</em> associated with it; each widget provides a mechanism for data input when you are editing (text box, select list, file upload, etc.). Each field type also has one or more display options, which determine how the field is displayed to site visitors. The widget and display options can be changed after you have created the field.') . '</dd>';
      $output .= '<dt>' . t('How many values the field will store') . '</dt>';
      $output .= '<dd>' . t('You can store one value, a specific maximum number of values, or an unlimited number of values in each field. For example, an employee identification number field might store a single number, whereas a phone number field might store multiple phone numbers. This setting can be changed after you have created the field, but if you reduce the maximum number of values, you may lose information.') . '</dd>';
      $output .= '</dl>';
      $output .= '<dt>' . t('Reusing fields') . '</dt>';
      $output .= '<dd>' . t('Once you have defined a field, you can reuse it. For example, if you define a custom image field for one content type, and you need to have an image field with the same parameters on another content type, you can add the same field to the second content type, in the <em>Re-use existing field</em> area of the user interface. You could also add this field to a taxonomy vocabulary, comments, user accounts, etc.') . '</dd>';
      $output .= '<dd>' . t('Some settings of a reused field are unique to each use of the field; others are shared across all places you use the field. For example, the label of a text field is unique to each use, while the setting for the number of values is shared.') . '</dd>';
      $output .= '<dd>' . t('There are two main reasons for reusing fields. First, reusing fields can save you time over defining new fields. Second, reusing fields also allows you to display, filter, group, and sort content together by field across content types. For example, the contributed Views module allows you to create lists and tables of content. So if you use the same field on multiple content types, you can create a View containing all of those content types together displaying that field, sorted by that field, and/or filtered by that field.') . '</dd>';
      if ($module_handler->moduleExists('node')) {
        $output .= '<dt>' . t('Fields on content items') . '</dt>';
        $output .= '<dd>' . t('Fields on content items are defined at the content-type level, on the <em>Manage fields</em> tab of the content type edit page (which you can reach from the <a href="@types">Content types page</a>). When you define a field for a content type, each content item of that type will have that field added to it. Some fields, such as the Title and Body, are provided for you when you create a content type, or are provided on content types created by your installation profile.', array('@types' => \Drupal::url('node.overview_types'))) . '</dd>';
      }
      if ($module_handler->moduleExists('taxonomy')) {
        $output .= '<dt>' . t('Fields on taxonomy terms') . '</dt>';
        $output .= '<dd>' . t('Fields on taxonomy terms are defined at the taxonomy vocabulary level, on the <em>Manage fields</em> tab of the vocabulary edit page (which you can reach from the <a href="@taxonomy">Taxonomy page</a>). When you define a field for a vocabulary, each term in that vocabulary will have that field added to it. For example, you could define an image field for a vocabulary to store an icon with each term.', array('@taxonomy' => \Drupal::url('taxonomy.vocabulary_list'))) . '</dd>';
      }
      $output .= '<dt>' . t('Fields on user accounts') . '</dt>';
      $output .= '<dd>' . t('Fields on user accounts are defined on a site-wide basis on the <a href="@fields">Manage fields tab</a> of the <a href="@accounts">Account settings</a> page. When you define a field for user accounts, each user account will have that field added to it. For example, you could add a long text field to allow users to include a biography.', array('@fields' => \Drupal::url('entity.user.field_ui_fields'), '@accounts' => \Drupal::url('entity.user.admin_form'))) . '</dd>';
      if ($module_handler->moduleExists('comment')) {
        $output .= '<dt>' . t('Fields on comments') . '</dt>';
        $output .= '<dd>' . t('Fields on comments are defined at the comment entity level, on the <em>Manage fields</em> tab of the comment types edit page (which you can reach from the <a href="@types">Comment types page</a>). When you add a field for comments, each comment on an entity with that comment type will have that field added to it. For example, you could add a website field to the comments on forum posts, to allow forum commenters to add a link to their website.', array('@types' => \Drupal::url('comment.type_list'))) . '</dd>';
      }
      $output .= '<dt>' . t('Managing view modes') . '</dt>';
      $output .= '<dd>' . t('Each content entity can have various "modes" for viewing. For instance, a content item could be viewed in full content mode on its own page, teaser mode in a list, or RSS mode in a feed. You can create, edit the names of, and delete view modes on the <a href="!view-modes">View modes page</a>. Once a view mode has been set up, you can choose and format fields for the view mode within each entity sub-type on the Manage display page. See the <a href="!field_ui">Field UI module help page</a> for more information.', array('!view-modes' => \Drupal::url('field_ui.entity_view_mode_list'), '!field_ui' => \Drupal::url('help.page', array('name' => 'field_ui')))) . '</dd>';
      $output .= '<dt>' . t('Managing form modes') . '</dt>';
      $output .= '<dd>' . t('Each content entity can have various editing forms appropriate for different situations, which are known as "form modes". For instance, you might want to define a quick editing mode that allows users to edit the most important fields, and a full editing mode that gives access to all the fields. You can create, edit the names of, and delete form modes on the <a href="!form-modes">Manage custom form modes page</a>. Once a form mode has been set up, you can choose which fields are available on that form within each entity sub-type on the Manage form display page. See the <a href="!field_ui">Field UI module help page</a> for more information.', array('!form-modes' => \Drupal::url('field_ui.entity_form_mode_list'), '!field_ui' => \Drupal::url('help.page', array('name' => 'field_ui')))) . '</dd>';
      $output .= '</dl>';
      return $output;

    case 'field_ui.list':
      return '<p>' . t('This list shows all fields currently in use for easy reference.') . '</p>';
  }
}

/**
 * Implements hook_theme().
 */
function field_ui_theme() {
  return array(
    'field_ui_table' => array(
      'render element' => 'elements',
      'function' => 'theme_field_ui_table',
    ),
  );
}

/**
 * Implements hook_entity_type_build().
 */
function field_ui_entity_type_build(array &$entity_types) {
  /** @var $entity_types \Drupal\Core\Entity\EntityTypeInterface[] */
  $entity_types['field_config']->setFormClass('delete', 'Drupal\field_ui\Form\FieldConfigDeleteForm');
  $entity_types['field_config']->setListBuilderClass('Drupal\field_ui\FieldConfigListBuilder');
  $entity_types['field_storage_config']->setListBuilderClass('Drupal\field_ui\FieldStorageConfigListBuilder');

  foreach ($entity_types as $entity_type) {
    if ($bundle = $entity_type->getBundleOf()) {
      // To generate links in the UI we use the route names, so we don't have to
      // know the exact required routes.
      // This allows us to not require route information inside this hook, which
      // otherwise could result in circular dependencies.
      $entity_type
        ->setLinkTemplate('field_ui-fields', "/admin/{$entity_type->id()}/fields")
        ->setLinkTemplate('field_ui-form-display', "/admin/{$entity_type->id()}/fields-form-display")
        ->setLinkTemplate('field_ui-display', "/admin/{$entity_type->id()}/fields-display");
    }
  }
}

/**
 * Implements hook_entity_bundle_create().
 */
function field_ui_entity_bundle_create($entity_type, $bundle) {
  // When a new bundle is created, the menu needs to be rebuilt to add our
  // menu item tabs.
  \Drupal::service('router.builder_indicator')->setRebuildNeeded();
}

/**
 * Implements hook_entity_bundle_rename().
 */
function field_ui_entity_bundle_rename($entity_type, $bundle_old, $bundle_new) {
  // When a bundle is renamed, the menu needs to be rebuilt to add our
  // menu item tabs.
  \Drupal::service('router.builder_indicator')->setRebuildNeeded();
}

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * Adds a button 'Save and manage fields' to the 'Create content type' form.
 *
 * @see node_type_form()
 * @see field_ui_form_node_type_form_submit()
 */
function field_ui_form_node_type_form_alter(&$form, FormStateInterface $form_state) {
  // We want to display the button only on add page.
  if ($form_state->getFormObject()->getEntity()->isNew()) {
    $form['actions']['save_continue'] = $form['actions']['submit'];
    $form['actions']['save_continue']['#value'] = t('Save and manage fields');
    $form['actions']['save_continue']['#weight'] = $form['actions']['save_continue']['#weight'] + 5;
    $form['actions']['save_continue']['#submit'][] = 'field_ui_form_node_type_form_submit';
    // Hide the 'Save content type' button.
    $form['actions']['submit']['#access'] = FALSE;
  }
}

/**
 * Implements hook_entity_operation().
 */
function field_ui_entity_operation(EntityInterface $entity) {
  $operations = array();
  $info = $entity->getEntityType();
  // Add manage fields and display links if this entity type is the bundle
  // of another and that type has field UI enabled.
  $entity_manager = \Drupal::entityManager();
  if (($bundle_of = $info->getBundleOf()) && $entity_manager->getDefinition($bundle_of)->get('field_ui_base_route')) {
    $account = \Drupal::currentUser();
    if ($account->hasPermission('administer '. $bundle_of . ' fields')) {
      $operations['manage-fields'] = array(
        'title' => t('Manage fields'),
        'weight' => 15,
        'url' => $entity->urlInfo('field_ui-fields'),
      );
    }
    if ($account->hasPermission('administer '. $bundle_of . ' form display')) {
      $operations['manage-form-display'] = array(
        'title' => t('Manage form display'),
        'weight' => 20,
        'url' => $entity->urlInfo('field_ui-form-display'),
      );
    }
    if ($account->hasPermission('administer '. $bundle_of . ' display')) {
      $operations['manage-display'] = array(
        'title' => t('Manage display'),
        'weight' => 25,
        'url' => $entity->urlInfo('field_ui-display'),
      );
    }
  }

  return $operations;
}

/**
 * Form submission handler for the 'Save and manage fields' button.
 *
 * @see field_ui_form_node_type_form_alter()
 */
function field_ui_form_node_type_form_submit($form, FormStateInterface $form_state) {
  if ($form_state->getTriggeringElement()['#parents'][0] === 'save_continue' && $route_info = FieldUI::getOverviewRouteInfo('node', $form_state->getValue('type'))) {
    $form_state->setRedirectUrl($route_info);
  }
}

/**
 * Implements hook_view_mode_presave().
 */
function field_ui_view_mode_presave(EntityViewModeInterface $view_mode) {
  \Drupal::service('router.builder_indicator')->setRebuildNeeded();
}

/**
 * Implements hook_view_mode_delete().
 */
function field_ui_view_mode_delete(EntityViewModeInterface $view_mode) {
  \Drupal::service('router.builder_indicator')->setRebuildNeeded();
}

/**
 * Returns HTML for Field UI overview tables.
 *
 * @param $variables
 *   An associative array containing:
 *   - elements: An associative array containing a Form API structure to be
 *     rendered as a table.
 *
 * @ingroup themeable
 */
function theme_field_ui_table($variables) {
  $elements = $variables['elements'];
  $table = array('#type' => 'table');

  // Add table headers and attributes.
  foreach (array('#header', '#attributes') as $key) {
    if (isset($elements[$key])) {
      $table[$key] = $elements[$key];
    }
  }

  // Determine the colspan to use for region rows, by checking the number of
  // columns in the headers.
  $columns_count = 0;
  foreach ($table['#header'] as $header) {
    $columns_count += (is_array($header) && isset($header['colspan']) ? $header['colspan'] : 1);
  }

  // Render rows, region by region.
  foreach ($elements['#regions'] as $region_name => $region) {
    $region_name_class = Html::getClass($region_name);

    // Add region rows.
    if (isset($region['title']) && empty($region['invisible'])) {
      $table['#rows'][] = array(
        'class' => array('region-title', 'region-' . $region_name_class . '-title'),
        'no_striping' => TRUE,
        'data' => array(
          array('data' => $region['title'], 'colspan' => $columns_count),
        ),
      );
    }
    if (isset($region['message'])) {
      $class = (empty($region['rows_order']) ? 'region-empty' : 'region-populated');
      $table['#rows'][] = array(
        'class' => array('region-message', 'region-' . $region_name_class . '-message', $class),
        'no_striping' => TRUE,
        'data' => array(
          array('data' => $region['message'], 'colspan' => $columns_count),
        ),
      );
    }

    // Add form rows, in the order determined at pre-render time.
    foreach ($region['rows_order'] as $name) {
      $element = $elements[$name];

      $row = array('data' => array());
      if (isset($element['#attributes'])) {
        $row += $element['#attributes'];
      }

      // Render children as table cells.
      foreach (Element::children($element) as $cell_key) {
        $child = &$element[$cell_key];
        // Do not render a cell for children of #type 'value'.
        if (!(isset($child['#type']) && $child['#type'] == 'value')) {
          $cell = array('data' => drupal_render($child));
          if (isset($child['#cell_attributes'])) {
            $cell += $child['#cell_attributes'];
          }
          $row['data'][] = $cell;
        }
      }
      $table['#rows'][] = $row;
    }
  }

  return drupal_render($table);
}

/**
 * Implements hook_local_tasks_alter().
 */
function field_ui_local_tasks_alter(&$local_tasks) {
  $container = \Drupal::getContainer();
  $local_task = FieldUiLocalTask::create($container, 'field_ui.fields');
  $local_task->alterLocalTasks($local_tasks);
}

/**
 * Implements hook_entity_type_alter().
 */
function field_ui_entity_type_alter(array &$entity_types) {
  /** @var $entity_types \Drupal\Core\Entity\EntityTypeInterface[] */
  $form_mode = $entity_types['entity_form_mode'];
  $form_mode->setListBuilderClass('Drupal\field_ui\EntityFormModeListBuilder');
  $form_mode->setFormClass('add', 'Drupal\field_ui\Form\EntityFormModeAddForm');
  $form_mode->setFormClass('edit', 'Drupal\field_ui\Form\EntityDisplayModeEditForm');
  $form_mode->setFormClass('delete', 'Drupal\field_ui\Form\EntityDisplayModeDeleteForm');
  $form_mode->set('admin_permission', 'administer display modes');
  $form_mode->setLinkTemplate('delete-form', '/admin/structure/display-modes/form/manage/{entity_form_mode}/delete');
  $form_mode->setLinkTemplate('edit-form', '/admin/structure/display-modes/form/manage/{entity_form_mode}');

  $view_mode = $entity_types['entity_view_mode'];
  $view_mode->setListBuilderClass('Drupal\field_ui\EntityDisplayModeListBuilder');
  $view_mode->setFormClass('add', 'Drupal\field_ui\Form\EntityDisplayModeAddForm');
  $view_mode->setFormClass('edit', 'Drupal\field_ui\Form\EntityDisplayModeEditForm');
  $view_mode->setFormClass('delete', 'Drupal\field_ui\Form\EntityDisplayModeDeleteForm');
  $view_mode->set('admin_permission', 'administer display modes');
  $view_mode->setLinkTemplate('delete-form', '/admin/structure/display-modes/view/manage/{entity_view_mode}/delete');
  $view_mode->setLinkTemplate('edit-form', '/admin/structure/display-modes/view/manage/{entity_view_mode}');
}