class RulesDataUI

class RulesDataUI {
  
  /**
   * Specifies the default input mode per data type.
   */
  public static function getDefaultMode() {
    return 'selector';
  }
  
  /**
   * Provides the selection form for a parameter.
   */
  public static function selectionForm($name, $info, $settings, RulesPlugin $element) {
    if (!isset($settings[$name . ':select'])) {
      $settings[$name . ':select'] = '';
      $vars = $element->availableVariables();
      // Default to variables with the same name as the parameter.
      if (isset($vars[$name])) {
        $settings[$name . ':select'] = $name;
      }
      elseif (count($matches = RulesData::matchingDataSelector($vars, $info, '', 1, FALSE)) == 1) {
        $settings[$name . ':select'] = rules_array_key($matches);
      }
    }
    $form[$name . ':select'] = array(
      '#type' => 'rules_data_selection',
      '#title' => t('Data selector'),
      '#default_value' => $settings[$name . ':select'],
      '#required' => empty($info['optional']),
      '#autocomplete_path' => RulesPluginUI::path($element->root()->name, 'autocomplete' . '/' . $name),
      // Make the autocomplete textfield big enough so that it can display
      // descriptions without word wraps.
'#size' => 75,
      '#description' => t("The data selector helps you drill down into the data available to Rules. <em>To make entity fields appear in the data selector, you may have to use the condition 'Entity has field' (or 'Entity is of bundle').</em> More useful tips about data selection are available in <a href='@url'>the online documentation</a>.", array(
        '@url' => rules_external_help('data-selection'),
      )),
    );
    $cache = rules_get_cache();
    $form['types_help'] = array(
      '#theme' => 'rules_settings_help',
      '#heading' => t('Data types'),
    );
    if ($info['type'] == '*') {
      $type_labels[] = t('any');
    }
    else {
      $types = is_array($info['type']) ? $info['type'] : array(
        $info['type'],
      );
      $type_labels = array();
      foreach ($types as $type) {
        $type_labels[] = drupal_ucfirst(isset($cache['data_info'][$type]['label']) ? $cache['data_info'][$type]['label'] : $type);
      }
    }
    $form['types_help']['#text'] = format_plural(count($type_labels), 'Select data of the type %types.', 'Select data of the types %types.', array(
      '%types' => implode(', ', $type_labels),
    ));
    if (!empty($info['translatable'])) {
      if (empty($info['custom translation language'])) {
        $text = t('If a multilingual data source (i.e. a translatable field) is given, the argument is translated to the current interface language.');
      }
      else {
        $text = t('If a multilingual data source (i.e. a translatable field) is given, the argument is translated to the configured language.');
      }
      $form['translation'] = array(
        '#theme' => 'rules_settings_help',
        '#text' => $text,
        '#heading' => t('Translation'),
      );
    }
    $form['help'] = array(
      '#theme' => 'rules_data_selector_help',
      '#variables' => $element->availableVariables(),
      '#parameter' => $info,
    );
    // Add data processor.
    $settings += array(
      $name . ':process' => array(),
    );
    $form[$name . ':process'] = array();
    RulesDataProcessor::attachForm($form[$name . ':process'], $settings[$name . ':process'], $info, $element->availableVariables());
    return $form;
  }
  
  /**
   * Renders the value with a label if an options list is available.
   *
   * Used for data UI classes implementing the
   * RulesDataDirectInputFormInterface.
   *
   * In case an options list is available, the usual render() method won't
   * be invoked, instead the selected entry is rendered via this method.
   *
   * @todo for Drupal 8: Refactor to avoid implementations have to care about
   * option lists when generating the form, but not when rendering values.
   */
  public static function renderOptionsLabel($value, $name, $info, RulesPlugin $element) {
    if (!empty($info['options list'])) {
      $element->call('loadBasicInclude');
      $options = entity_property_options_flatten(call_user_func($info['options list'], $element, $name));
      if (!is_array($value) && isset($options[$value])) {
        $value = $options[$value];
      }
      elseif (is_array($value)) {
        foreach ($value as $key => $single_value) {
          if (isset($options[$single_value])) {
            $value[$key] = $options[$single_value];
          }
        }
        $value = implode(', ', $value);
      }
      return array(
        'content' => array(
          '#markup' => check_plain($value),
        ),
        '#attributes' => array(
          'class' => array(
            'rules-parameter-options-entry',
          ),
        ),
      );
    }
  }
  
  /**
   * Returns the data type and parameter information for the given arguments.
   *
   * This helper may be used by options list callbacks operation at data-type
   * level, see RulesDataInputOptionsListInterface.
   */
  public static function getTypeInfo(RulesPlugin $element, $name) {
    $parameters = $element->pluginParameterInfo();
    return array(
      $parameters[$name]['type'],
      $parameters[$name],
    );
  }

}