<?php

/**
 * @file
 * Contains draggableviews.module.
 */

/**
 * Implements hook_views_data_alter().
 */
function draggableviews_views_data_alter(&$data) {
  $data['draggableviews_structure']['weight'] = array(
    'title' => t('DraggableViews Weight'),
    'group' => t('Global'),
    'help' => t('Display the weight value.'),
    'field' => array(
      'id' => 'numeric',
    ),
    'sort' => array(
      'id' => 'standard',
    ),
    'filter' => array(
      'help' => t('Filter by the draggableviews weight value (Native handler only).'),
      'id' => 'numeric',
    ),
  );
  $data['draggableviews_structure']['parent'] = array(
    'title' => t('Parent'),
    'help' => t('The parent entity id.'),
    'group' => t('Draggableviews'),
    'field' => array(
      'id' => 'numeric',
    ),
    'filter' => array(
      'help' => t('Filter by the draggableviews parent\'s entity id (Native handler only).'),
      'id' => 'numeric',
    ),
  );

  foreach (\Drupal::entityManager()->getDefinitions() as $entity_type_id => $entity_type) {
    $base_table = $entity_type->getDataTable() ?: $entity_type->getBaseTable();
    $entity_keys = $entity_type->getKeys();
    if ($base_table && isset($data[$base_table]['table'])) {
      $data[$base_table]['draggableviews'] = array(
        'title' => $data[$base_table]['table']['group'],
        'group' => t('Draggableviews'),
        'help' => t('Provide a draggable functionality.'),
        'entity field' => $entity_keys['id'],
        'field' => array(
          'id' => 'draggable_views_field',
          'click sortable' => FALSE,
        ),
      );
      // Explain to every entity how to join with draggableviews structure table.
      $data['draggableviews_structure']['table']['join'][$base_table] = array(
        'handler' => 'draggableviews_join_handler',
        // Because this is a direct link it could be left out.
        'left_table' => $base_table,
        'left_field' => $entity_keys['id'],
        'field' => 'entity_id',
        'extra' => array(
          array('field' => 'view_name', 'value' => '***VIEW_ID***'),
          array('field' => 'view_display', 'value' => '***VIEW_DISPLAY***'),
        ),
      );
    }
  }
}

/**
 * Implements hook_views_query_substitutions().
 *
 * Allow replacement of current userid so we can cache these queries.
 */
function draggableviews_views_query_substitutions(\Drupal\views\ViewExecutable $view) {
  return array('***VIEW_ID***' => $view->id(), '***VIEW_DISPLAY***' => $view->current_display);
}

/**
 * Implements hook_preprocess_views_view_table().
 */
function draggableviews_preprocess_views_view_table(&$variables) {
  $view = $variables['view'];
  if (!isset($view->field['draggableviews'])) {
    return;
  }

  $draggableviews = new \Drupal\draggableviews\DraggableViews($variables['view']);

  // Add hierarchy.
  foreach ($variables['rows'] as $key => $row) {
    $title = $row['columns']['title']['content'][0]['field_output']['#markup'];
    $indent = [
      '#theme' => 'indentation',
      '#size' => $draggableviews->getDepth($key),
    ];
    $variables['rows'][$key]['columns']['title']['content'][0]['field_output']['#markup'] = render($indent) . $title;
  }

  // Add table attributes.
  $variables['attributes']['id'] = $draggableviews->getHtmlId();

  // Add rows attributes.
  foreach ($variables['rows'] as &$row) {
    $row['attributes']->addClass('draggable');
  }
  unset($row);
}

/**
 * Implements hook_form_alter().
 */
function draggableviews_form_alter(&$form, \Drupal\Core\Form\FormStateInterface $form_state, $form_id) {
  // Filter the right form.
  if (strpos($form_id, 'views_form_') === FALSE) {
    return;
  }

  // Check whether the view is draggable.
  $view = $form_state->getBuildInfo()['args'][0];
  if (!isset($view->field['draggableviews'])) {
    return;
  }

  // Remove default submit button.
  $form['actions']['submit']['#access'] = FALSE;

  if (\Drupal::currentUser()->hasPermission('access draggableviews')) {
    // Create draggableviews save order button.
    $form['actions']['save_order'] = array(
      '#value' => t('Save order'),
      '#type' => 'submit',
    );
  }

  // If there is no results remove the save-order button.
  if (!isset($form['draggableviews'][0])) {
    $form['actions']['save_order']['#access'] = FALSE;
    return;
  }

  $form['actions']['save_order']['#submit'][] = 'draggableviews_views_submit';
}

/**
 * Submit handler.
 */
function draggableviews_views_submit(&$form, \Drupal\Core\Form\FormStateInterface $form_state) {
  $input = $form_state->getUserInput();

  /** @var \Drupal\views\ViewExecutable $view */
  $view = $form_state->getBuildInfo()['args'][0];
  $view_name = $view->id();
  $view_display = $view->current_display;

  $weight = 0;

  $connection = \Drupal\Core\Database\Database::getConnection();
  $transaction = $connection->startTransaction();
  try {
    foreach ($input['draggableviews'] as $item) {
      // Remove old data.
      $connection->delete('draggableviews_structure')
        ->condition('view_name', $view_name)
        ->condition('view_display', $view_display)
        ->condition('entity_id', $item['id'])
        ->execute();

      // Add new data.
      $record = [
        'view_name' => $view_name,
        'view_display' => $view_display,
        'args' => '[]',
        'entity_id' => $item['id'],
        'weight' => $weight,
      ];
      // Save parent if exists.
      if (isset($item['parent'])) {
        $record['parent'] = $item['parent'];
      }
      $connection->insert('draggableviews_structure')->fields($record)->execute();
      $weight++;
    }
    // We invalidate the entity list cache, so other views are also aware of the
    // cache.
    $views_entity_table_info = $view->query->getEntityTableInfo();
    // Find the entity type used by the view.
    $result = array_keys(array_filter($views_entity_table_info, function($info) {
      return $info['relationship_id'] == 'none';
    }));
    $entity_type_id = reset($result);
    $list_cache_tags = \Drupal::entityTypeManager()->getDefinition($entity_type_id)->getListCacheTags();
    \Drupal\Core\Cache\Cache::invalidateTags($list_cache_tags);
  }
  catch (\Exception $e) {
    $transaction->rollback();
    \Drupal::logger('draggableviews')->error('Failed with @message', ['@message' => $e->getMessage()]);
    drupal_set_message(t('There was an error while saving the data. Please, try gain.'), 'warning');
  }
}