class DefaultSummary

class DefaultSummary extends StylePluginBase {
  
  /**
   * {@inheritdoc}
   */
  protected function defineOptions() {
    $options = parent::defineOptions();
    $options['base_path'] = [
      'default' => '',
    ];
    $options['count'] = [
      'default' => TRUE,
    ];
    $options['override'] = [
      'default' => FALSE,
    ];
    $options['items_per_page'] = [
      'default' => 25,
    ];
    return $options;
  }
  
  /**
   * {@inheritdoc}
   */
  public function query() {
    if (!empty($this->options['override'])) {
      $this->view
        ->setItemsPerPage(intval($this->options['items_per_page']));
    }
  }
  
  /**
   * {@inheritdoc}
   */
  public function buildOptionsForm(&$form, FormStateInterface $form_state) {
    $form['base_path'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Base path'),
      '#default_value' => $this->options['base_path'],
      '#description' => $this->t('Define the base path for links in this summary
        view, i.e. http://example.com/<strong>your_view_path/archive</strong>.
        Do not include beginning and ending forward slash. If this value
        is empty, views will use the first path found as the base path,
        in page displays, or / if no path could be found.'),
    ];
    $form['count'] = [
      '#type' => 'checkbox',
      '#default_value' => !empty($this->options['count']),
      '#title' => $this->t('Display record count with link'),
    ];
    $form['override'] = [
      '#type' => 'checkbox',
      '#default_value' => !empty($this->options['override']),
      '#title' => $this->t('Override number of items to display'),
    ];
    $form['items_per_page'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Items to display'),
      '#default_value' => $this->options['items_per_page'],
      '#states' => [
        'visible' => [
          ':input[name="options[summary][options][' . $this->definition['id'] . '][override]"]' => [
            'checked' => TRUE,
          ],
        ],
      ],
    ];
  }
  
  /**
   * {@inheritdoc}
   */
  public function render() {
    $rows = [];
    foreach ($this->view->result as $row) {
      // @todo Include separator as an option.
      $rows[] = $row;
    }
    return [
      '#theme' => $this->themeFunctions(),
      '#view' => $this->view,
      '#options' => $this->options,
      '#rows' => $rows,
    ];
  }

}