class Boolean

class Boolean extends FieldPluginBase {
  
  /**
   * {@inheritdoc}
   */
  protected function defineOptions() {
    $options = parent::defineOptions();
    $options['type'] = [
      'default' => 'yes-no',
    ];
    $options['type_custom_true'] = [
      'default' => '',
    ];
    $options['type_custom_false'] = [
      'default' => '',
    ];
    $options['not'] = [
      'default' => FALSE,
    ];
    return $options;
  }
  
  /**
   * {@inheritdoc}
   */
  public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
    parent::init($view, $display, $options);
    $default_formats = [
      'yes-no' => [
        $this->t('Yes'),
        $this->t('No'),
      ],
      'true-false' => [
        $this->t('True'),
        $this->t('False'),
      ],
      'on-off' => [
        $this->t('On'),
        $this->t('Off'),
      ],
      'enabled-disabled' => [
        $this->t('Enabled'),
        $this->t('Disabled'),
      ],
      'boolean' => [
        1,
        0,
      ],
      'unicode-yes-no' => [
        '✔',
        '✖',
      ],
    ];
    $output_formats = $this->definition['output formats'] ?? [];
    $custom_format = [
      'custom' => [
        $this->t('Custom'),
      ],
    ];
    $this->formats = array_merge($default_formats, $output_formats, $custom_format);
  }
  
  /**
   * {@inheritdoc}
   */
  public function buildOptionsForm(&$form, FormStateInterface $form_state) {
    foreach ($this->formats as $key => $item) {
      $options[$key] = implode('/', $item);
    }
    $form['type'] = [
      '#type' => 'select',
      '#title' => $this->t('Output format'),
      '#options' => $options,
      '#default_value' => $this->options['type'],
    ];
    $form['type_custom_true'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Custom output for TRUE'),
      '#default_value' => $this->options['type_custom_true'],
      '#states' => [
        'visible' => [
          'select[name="options[type]"]' => [
            'value' => 'custom',
          ],
        ],
      ],
    ];
    $form['type_custom_false'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Custom output for FALSE'),
      '#default_value' => $this->options['type_custom_false'],
      '#states' => [
        'visible' => [
          'select[name="options[type]"]' => [
            'value' => 'custom',
          ],
        ],
      ],
    ];
    $form['not'] = [
      '#type' => 'checkbox',
      '#title' => $this->t('Reverse'),
      '#description' => $this->t('If checked, true will be displayed as false.'),
      '#default_value' => $this->options['not'],
    ];
    parent::buildOptionsForm($form, $form_state);
  }
  
  /**
   * {@inheritdoc}
   */
  public function render(ResultRow $values) {
    $value = $this->getValue($values);
    if (!empty($this->options['not'])) {
      $value = !$value;
    }
    if ($this->options['type'] == 'custom') {
      $custom_value = $value ? $this->options['type_custom_true'] : $this->options['type_custom_false'];
      return ViewsRenderPipelineMarkup::create(UtilityXss::filterAdmin($custom_value));
    }
    elseif (isset($this->formats[$this->options['type']])) {
      return $value ? $this->formats[$this->options['type']][0] : $this->formats[$this->options['type']][1];
    }
    else {
      return $value ? $this->formats['yes-no'][0] : $this->formats['yes-no'][1];
    }
  }

}