<?php

namespace Drupal\webform_options_limit\Plugin\WebformHandler;

use Drupal\Component\Render\FormattableMarkup;
use Drupal\Core\Cache\Cache;
use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Form\OptGroup;
use Drupal\Core\Render\Element;
use Drupal\webform\Element\WebformAjaxElementTrait;
use Drupal\webform\Element\WebformEntityTrait;
use Drupal\webform\Element\WebformMessage;
use Drupal\webform\Plugin\WebformElement\BooleanBase;
use Drupal\webform\Plugin\WebformElement\OptionsBase;
use Drupal\webform\Plugin\WebformElement\TableSelect;
use Drupal\webform\Plugin\WebformElementEntityOptionsInterface;
use Drupal\webform\Plugin\WebformHandlerBase;
use Drupal\webform\Utility\WebformOptionsHelper;
use Drupal\webform\WebformSubmissionInterface;
use Drupal\webform_options_limit\Plugin\WebformOptionsLimitHandlerInterface;
use Symfony\Component\DependencyInjection\ContainerInterface;

/**
 * Webform options and boolean (boolean) limit handler.
 *
 * @WebformHandler(
 *   id = "options_limit",
 *   label = @Translation("Options/Checkbox limit"),
 *   category = @Translation("Options"),
 *   description = @Translation("Define options or checkbox submission limits."),
 *   cardinality = \Drupal\webform\Plugin\WebformHandlerInterface::CARDINALITY_UNLIMITED,
 *   results = \Drupal\webform\Plugin\WebformHandlerInterface::RESULTS_IGNORED,
 *   submission = \Drupal\webform\Plugin\WebformHandlerInterface::SUBMISSION_REQUIRED,
 * )
 */
class OptionsLimitWebformHandler extends WebformHandlerBase implements WebformOptionsLimitHandlerInterface {

  use WebformAjaxElementTrait;

  /**
   * The database object.
   *
   * @var \Drupal\Core\Database\Connection
   */
  protected $database;

  /**
   * The current user.
   *
   * @var \Drupal\Core\Session\AccountInterface
   */
  protected $currentUser;

  /**
   * The webform token manager.
   *
   * @var \Drupal\webform\WebformTokenManagerInterface
   */
  protected $tokenManager;

  /**
   * The webform element plugin manager.
   *
   * @var \Drupal\webform\Plugin\WebformElementManagerInterface
   */
  protected $elementManager;

  /**
   * The source entity.
   *
   * @var \Drupal\Core\Entity\EntityInterface
   */
  protected $sourceEntity = NULL;

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
    $instance = parent::create($container, $configuration, $plugin_id, $plugin_definition);
    $instance->database = $container->get('database');
    $instance->currentUser = $container->get('current_user');
    $instance->tokenManager = $container->get('webform.token_manager');
    $instance->elementManager = $container->get('plugin.manager.webform.element');
    return $instance;
  }

  /**
   * {@inheritdoc}
   */
  public function hasAnonymousSubmissionTracking() {
    return $this->configuration['limit_user'];
  }

  /**
   * {@inheritdoc}
   */
  public function setSourceEntity(EntityInterface $source_entity = NULL) {
    $this->sourceEntity = $source_entity;
    return $this;
  }

  /**
   * {@inheritdoc}
   */
  public function getSourceEntity() {
    if ($this->sourceEntity) {
      return $this->sourceEntity;
    }
    elseif ($this->getWebformSubmission()) {
      return $this->getWebformSubmission()->getSourceEntity();
    }
    else {
      return NULL;
    }
  }

  /**
   * {@inheritdoc}
   */
  public function defaultConfiguration() {
    return [
      'element_key' => '',
      // Boolean limit.
      'limit' => NULL,
      // Options limit.
      'limits' => [],
      'limit_reached_message' => '@name is not available',
      'limit_source_entity' => TRUE,
      'limit_user' => FALSE,
      'option_none_action' => 'disable',
      'option_message_display' => 'label',
      'option_multiple_message' => '[@remaining remaining]',
      'option_single_message' => '[@remaining remaining]',
      'option_unlimited_message' => '[Unlimited]',
      'option_none_message' => '[@remaining remaining]',
      'option_error_message' => '@name: @label is unavailable.',
      'tableselect_header' => '',
    ];
  }

  /**
   * {@inheritdoc}
   */
  public function getSummary() {
    $settings = $this->getSettings();

    $element = $this->getWebform()->getElement($settings['element_key']);
    if ($element) {
      $webform_element = $this->elementManager->getElementInstance($element);
      $t_args = [
        '@title' => $webform_element->getAdminLabel($element),
        '@type' => $webform_element->getPluginLabel(),
      ];
      $settings['element_key'] = $this->t('@title (@type)', $t_args);
    }
    elseif (empty($settings['element_key'])) {
      $settings['element_key'] = [
        '#type' => 'link',
        '#title' => $this->t('Please add a new options or checkbox element.'),
        '#url' => $this->getWebform()->toUrl('edit-form'),
      ];
    }
    else {
      $settings['element_key'] = [
        '#markup' => $this->t("'@element_key' is missing.", ['@element_key' => $settings['element_key']]),
        '#prefix' => '<b class="color-error">',
        '#suffix' => '</b>',
      ];
    }

    // Unset limit if element type is not a boolean.
    if (!$this->isBooleanElement()) {
      unset($settings['limit']);
    }

    return [
      '#settings' => $settings,
    ] + parent::getSummary();
  }

  /**
   * {@inheritdoc}
   */
  public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
    $this->applyFormStateToConfiguration($form_state);

    // Get elements with options.
    $elements_with_options = $this->getElements();

    // Make sure that there an options element available.
    if (empty($elements_with_options)) {
      $form['message'] = [
        '#type' => 'webform_message',
        '#message_type' => 'warning',
        '#message_message' => [
          'message' => [
            '#markup' => $this->t('No options or checkbox elements are available.'),
            '#prefix' => '<p>',
            '#suffix' => '</p>',
          ],
          'link' => [
            '#type' => 'link',
            '#title' => $this->t('Please add a new options or checkbox element.'),
            '#url' => $this->getWebform()->toUrl('edit-form'),
            '#prefix' => '<p>',
            '#suffix' => '</p>',
          ],
        ],
      ];
      return $form;
    }

    // Element settings.
    $form['element_settings'] = [
      '#type' => 'details',
      '#title' => $this->t('Element settings'),
      '#open' => TRUE,
    ];
    $form['element_settings']['element_key'] = [
      '#type' => 'select',
      '#title' => $this->t('Element'),
      '#options' => $this->getElements(),
      '#default_value' => $this->configuration['element_key'],
      '#required' => TRUE,
      '#empty_option' => (empty($this->configuration['element_key'])) ? $this->t('- Select -') : NULL,
    ];
    $form['element_settings']['options_container'] = [];
    $element = $this->getElement();
    if ($element) {
      $webform_element = $this->getWebformElement();
      $t_args = [
        '@title' => $webform_element->getAdminLabel($element),
        '@type' => $this->t('option'),
      ];

      if ($this->isOptionsElement()) {
        $element_options = $this->getElementOptions() + [
          WebformOptionsLimitHandlerInterface::DEFAULT_LIMIT => $this->t('Default (Used when option has no limit)'),
        ];
        $form['element_settings']['options_container']['limits'] = [
          '#type' => 'webform_mapping',
          '#title' => $this->t('@title @type limits', $t_args),
          '#description_display' => 'before',
          '#source' => $element_options,
          '#source__title' => $this->t('Options'),
          '#destination__type' => 'number',
          '#destination__min' => 0,
          '#destination__title' => $this->t('Limit'),
          '#destination__description' => NULL,
          '#default_value' => $this->configuration['limits'],
          '#filter' => FALSE,
        ];
      }
      else {
        $form['element_settings']['options_container']['limit'] = [
          '#type' => 'number',
          '#title' => $this->t('@title @type limit', $t_args),
          '#min' => 0,
          '#default_value' => $this->configuration['limit'],
        ];
      }
    }
    else {
      $form['element_settings']['options_container']['limits'] = [
        '#type' => 'value',
        '#value' => [],
      ];
      $form['element_settings']['options_container']['limit'] = [
        '#type' => 'value',
        '#value' => NULL,
      ];
    }
    $this->buildAjaxElement(
      'webform-options-limit',
      $form['element_settings']['options_container'],
      $form['element_settings']['element_key']
    );

    // Limit settings.
    $form['limit_settings'] = [
      '#type' => 'details',
      '#title' => $this->t('Limit settings'),
    ];
    $form['limit_settings']['limit_reached_message'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Limit reached message'),
      '#description' => $this->t('This message will be displayed when all limits are reached.')
        . '<br/><br/>'
        . $this->t('Leave blank to hide this message.'),
      '#default_value' => $this->configuration['limit_reached_message'],
    ];
    $form['limit_settings']['limit_source_entity'] = [
      '#type' => 'checkbox',
      '#title' => $this->t('Apply limits to each source entity'),
      '#description' => $this->t('If checked, limits will be applied to this webform and each source entity individually.'),
      '#return_value' => TRUE,
      '#default_value' => $this->configuration['limit_source_entity'],
    ];
    $form['limit_settings']['limit_user'] = [
      '#type' => 'checkbox',
      '#title' => $this->t('Apply limits to per user'),
      '#description' => $this->t("If checked, limits will be applied per submission for authenticated and anonymous users. Anonymous user limits are only tracked by the user's browser sessions. Per user limits work best for authenticated users."),
      '#return_value' => TRUE,
      '#default_value' => $this->configuration['limit_user'],
    ];
    $form['limit_settings']['limit_user_message'] = [
      '#type' => 'webform_message',
      '#message_type' => 'warning',
      '#message_message' => $this->t("Anonymous user limits are only tracked by the user's browser session. It is recommended that limits per user only be used on forms restricted to authenticated users."),
      '#message_close' => TRUE,
      '#message_storage' => WebformMessage::STORAGE_SESSION,
      '#states' => [
        'visible' => [
          ':input[name="settings[limit_user]"]' => ['checked' => TRUE],
        ],
      ],
    ];
    // Option settings.
    $form['option_settings'] = [
      '#type' => 'details',
      '#title' => $this->t('Option/checkbox settings'),
    ];
    $form['option_settings']['option_none_action'] = [
      '#type' => 'select',
      '#title' => $this->t('Limit reached behavior'),
      '#options' => [
        WebformOptionsLimitHandlerInterface::LIMIT_ACTION_DISABLE => $this->t('Disable the option/checkbox'),
        WebformOptionsLimitHandlerInterface::LIMIT_ACTION_REMOVE => $this->t('Remove the option/checkbox'),
        WebformOptionsLimitHandlerInterface::LIMIT_ACTION_NONE => $this->t('Do not alter the option/checkbox'),
      ],
      '#default_value' => $this->configuration['option_none_action'],
    ];
    $form['option_settings']['option_message_display'] = [
      '#type' => 'select',
      '#title' => $this->t('Message display'),
      '#options' => [
        WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_LABEL => $this->t("Append message to the option/checkbox's text"),
        WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_DESCRIPTION => $this->t("Append message to the option/checkbox's description"),
        WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_NONE => $this->t("Do not display a message"),
      ],
      '#default_value' => $this->configuration['option_message_display'],
    ];
    $form['option_settings']['option_message'] = [
      '#type' => 'container',
      '#states' => [
        'visible' => [
          ':input[name="settings[option_message_display]"]' => ['!value' => 'none'],
        ],
      ],
    ];
    $form['option_settings']['option_message']['option_multiple_message'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Multiple remaining message'),
      '#description' => $this->t('This message is displayed when the remaining submission is greater than one.')
        . '<br/><br/>'
        . $this->t('Leave blank to hide this message.'),
      '#default_value' => $this->configuration['option_multiple_message'],
    ];
    $form['option_settings']['option_message']['option_single_message'] = [
      '#type' => 'textfield',
      '#title' => $this->t('One remaining message'),
      '#description' => $this->t('This message is displayed when there is only one remaining submission available.')
        . '<br/><br/>'
        . $this->t('Leave blank to hide this message.'),
      '#default_value' => $this->configuration['option_single_message'],
    ];
    $form['option_settings']['option_message']['option_none_message'] = [
      '#type' => 'textfield',
      '#title' => $this->t('None remaining message'),
      '#description' => $this->t('This message is displayed when there are remaining submissions allows.')
        . '<br/><br/>'
        . $this->t('Leave blank to hide this message.'),
      '#default_value' => $this->configuration['option_none_message'],
    ];
    $form['option_settings']['option_message']['option_unlimited_message'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Unlimited message'),
      '#description' => $this->t('This message is displayed when there are not submissions limits.')
        . '<br/><br/>'
        . $this->t('Leave blank to hide this message.'),
      '#default_value' => $this->configuration['option_unlimited_message'],
    ];
    $form['option_settings']['option_error_message'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Validation error message'),
      '#description' => $this->t('The message is displayed when an element has validation error is submitted.'),
      '#default_value' => $this->configuration['option_error_message'],
      '#required' => TRUE,
    ];
    if ($tableselect_elements = $this->getTableSelectElements()) {
      $tableselect_states = [];
      foreach ($tableselect_elements as $tableselect_element_key) {
        if ($tableselect_states) {
          $tableselect_states[] = 'or';
        }
        $tableselect_states[] = [':input[name="settings[element_key]"]' => ['value' => $tableselect_element_key]];
      }
      $form['option_settings']['tableselect_header'] = [
        '#type' => 'textfield',
        '#title' => $this->t('Table select description header'),
        '#description' => $this->t("The label is displayed in the header for the table select's option limit column."),
        '#default_value' => $this->configuration['tableselect_header'],
        '#states' => [
          'visible' => [
            ':input[name="settings[option_message_display]"]' => ['value' => WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_DESCRIPTION],
            $tableselect_states,
          ],
        ],
      ];
    }

    // Placeholder help.
    $form['placeholder_help'] = [
      '#type' => 'details',
      '#title' => $this->t('Placeholder help'),
      'description' => [
        '#markup' => $this->t('The following placeholders can be used:'),
      ],
      'items' => [
        '#theme' => 'item_list',
        '#items' => [
          $this->t('@limit - The total number of submissions allowed for the option/checkbox.'),
          $this->t('@total - The current number of submissions for the option/checkbox.'),
          $this->t('@remaining - The remaining number of submissions for the option/checkbox.'),
          $this->t("@label - The element option/checkbox's label."),
          $this->t("@name - The element's title."),
        ],
      ],
    ];

    return $this->setSettingsParents($form);
  }

  /**
   * {@inheritdoc}
   */
  public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
    parent::submitConfigurationForm($form, $form_state);
    $this->applyFormStateToConfiguration($form_state);

    foreach ($this->configuration['limits'] as $key => $value) {
      if ($value === '') {
        unset($this->configuration['limits'][$key]);
      }
      else {
        $this->configuration['limits'][$key] = (int) $value;
      }
    }
    if ($this->isOptionsElement()) {
      $this->configuration['limit'] = NULL;
    }
    else {
      $this->configuration['limits'] = [];
    }
  }

  /****************************************************************************/
  // Alter element methods.
  /****************************************************************************/

  /**
   * {@inheritdoc}
   */
  public function alterElement(array &$element, FormStateInterface $form_state, array $context) {
    if (empty($element['#webform_key'])
      || $element['#webform_key'] !== $this->configuration['element_key']) {
      return;
    }

    // Set webform submission for form object.
    /** @var \Drupal\webform\WebformSubmissionForm $form_object */
    $form_object = $form_state->getFormObject();
    $operation = $form_object->getOperation();

    /** @var \Drupal\webform\WebformSubmissionInterface $webform_submission */
    $webform_submission = $form_object->getEntity();
    $this->setWebformSubmission($webform_submission);

    if ($this->isOptionsElement()) {
      // Get options limits, reached, and (form) operation.
      $limits = $this->getOptionsLimits();
      $reached = $this->getOptionsReached($limits);

      // Set table select description in header.
      if ($this->isTableSelectElement()) {
        $message_display = $this->configuration['option_message_display'];
        if ($message_display === WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_DESCRIPTION) {
          $element['#header']['webform_options_limit'] = $this->configuration['tableselect_header'] ?: '';
        }
      }

      // Cleanup options element default value.
      $this->setOptionsElementDefaultValue($element, $limits, $reached, $operation);

      // Alter options element.
      $this->alterOptionsElement($element, $limits, $reached);
    }
    else {
      // Get boolean limit.
      $limits = $this->getBooleanLimits();
      $limit = reset($limits);

      // Cleanup boolean element default value.
      $this->setBooleanElementDefaultValue($element, $limit, $operation);

      // Alter boolean element.
      $this->alterBooleanElement($element, $limit);
    }

    // Add element validate callback.
    $element['#webform_option_limit_handler_id'] = $this->getHandlerId();
    $element['#element_validate'][] = [get_called_class(), 'validateElement'];
  }

  /****************************************************************************/
  // Element methods.
  /****************************************************************************/

  /**
   * Validate webform element limit.
   */
  public static function validateElement(&$element, FormStateInterface $form_state, &$complete_form) {
    // Skip if element is not visible.
    if (!Element::isVisibleElement($element)) {
      return;
    }

    /** @var \Drupal\webform\WebformSubmissionForm $form_object */
    $form_object = $form_state->getFormObject();
    $webform = $form_object->getWebform();

    /** @var \Drupal\webform_options_limit\Plugin\WebformHandler\OptionsLimitWebformHandler $handler */
    $handler = $webform->getHandler($element['#webform_option_limit_handler_id']);
    if ($handler->isOptionsElement()) {
      $handler->validateOptionsElement($element, $form_state);
    }
    else {
      $handler->validateBooleanElement($element, $form_state);
    }
  }

  /**
   * Set element's limit reached message.
   *
   * @param array $element
   *   An element with limits.
   */
  protected function setElementLimitReachedMessage(array &$element) {
    if (empty($this->configuration['limit_reached_message'])) {
      return;
    }

    $args = ['@name' => $this->getElementLabel()];
    $element['#description'] = [
      '#type' => 'webform_message',
      '#message_type' => 'warning',
      '#message_message' => new FormattableMarkup($this->configuration['limit_reached_message'], $args),
    ];
  }

  /****************************************************************************/
  // Options element methods.
  /****************************************************************************/

  /**
   * Set an options element's default value.
   *
   * @param array $element
   *   An options element with limits.
   * @param array $limits
   *   An options element's option limits.
   * @param array $reached
   *   An options element's reached options.
   * @param string $operation
   *   The form's current operation.
   */
  protected function setOptionsElementDefaultValue(array &$element, array $limits, array $reached, $operation) {
    $webform_element = $this->getWebformElement();
    $has_multiple_values = $webform_element->hasMultipleValues($element);
    // Make sure the test default value is an enabled option.
    if ($operation === 'test') {
      $test_values = array_keys($reached ? array_diff_key($limits, $reached) : $limits);
      if ($test_values) {
        $test_value = $test_values[array_rand($test_values)];
        $element['#default_value'] = ($has_multiple_values) ? [$test_value] : $test_value;
      }
      else {
        $element['#default_value'] = ($has_multiple_values) ? [] : NULL;
      }
    }
    // Cleanup default values.
    elseif (!empty($element['#default_value'])) {
      $default_value = $element['#default_value'];
      if ($has_multiple_values) {
        if ($this->isTableSelectElement()) {
          $element['#default_value'] = array_diff($default_value, $reached);
        }
        else {
          $element['#default_value'] = array_values(array_diff($default_value, $reached));
        }
      }
      else {
        if (isset($reached[$default_value])) {
          $element['#default_value'] = ($has_multiple_values) ? [] : NULL;
        }
      }
    }
  }

  /**
   * Alter an options element.
   *
   * @param array $element
   *   An options element with limits.
   * @param array $limits
   *   An options element's option limits.
   * @param array $reached
   *   An options element's reached options.
   */
  protected function alterOptionsElement(array &$element, array $limits, array $reached) {
    // Set options element's options labels.
    $options =& $element['#options'];
    $this->alterOptionsElementLabels($options, $limits);

    // Disable or remove reached options.
    if ($reached) {
      switch ($this->configuration['option_none_action']) {
        case WebformOptionsLimitHandlerInterface::LIMIT_ACTION_DISABLE:
          $this->disableOptionsElement($element, $reached);
          break;

        case WebformOptionsLimitHandlerInterface::LIMIT_ACTION_REMOVE:
          $this->removeOptionsElement($element, $reached);
          break;
      }
    }

    // Display limit reached message.
    if (count($limits) === count($reached)) {
      $this->setElementLimitReachedMessage($element);
    }
  }

  /**
   * Alter an options element's option labels recursively.
   *
   * @param array $options
   *   An options element with limits.
   * @param array $limits
   *   An options element's option limits.
   */
  protected function alterOptionsElementLabels(array &$options, array $limits) {
    $message_display = $this->configuration['option_message_display'];
    foreach ($options as $option_value => $option_text) {
      if ($this->isTableSelectElement()) {
        if (isset($limits[$option_value])) {
          $label = $this->getOptionsLimitLabel(
            $option_text[0]['value'],
            $limits[$option_value]
          );
          $message_display = $this->configuration['option_message_display'];
          $option =& $options[$option_value][0];
          switch ($message_display) {
            case WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_DESCRIPTION:
              list(
                $option['value'],
                $option['webform_options_limit']) = explode(' --', $label);
              break;

            case WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_LABEL:
              $option['value'] = $label;
              break;
          }
        }
      }
      elseif (is_array($option_text)) {
        $this->alterOptionsElementLabels($option_text, $limits);
      }
      elseif (isset($limits[$option_value])) {
        $options[$option_value] = $this->getOptionsLimitLabel(
          $option_text,
          $limits[$option_value]
        );
      }
    }
  }

  /**
   * Disable options element's reached options.
   *
   * @param array $element
   *   An options element with limits.
   * @param array $reached
   *   An options element's reached options.
   */
  protected function disableOptionsElement(array &$element, array $reached) {
    $webform_element = $this->getWebformElement();
    if ($this->isTableSelectElement()) {
      // Hide disabled table select checkbox or radio.
      foreach ($reached as $reached_option) {
        $element[$reached_option]['#access'] = FALSE;
      }
    }
    elseif ($webform_element->hasProperty('options__properties')) {
      // Set element options disabled properties.
      foreach ($reached as $reached_option) {
        $element['#options__properties'][$reached_option] = [
          '#disabled' => TRUE,
        ];
      }
    }
    else {
      // Set select menu disabled attribute.
      // @see Drupal.behaviors.webformSelectOptionsDisabled
      // @see webform.element.select.js
      $element['#attributes']['data-webform-select-options-disabled'] = implode(',', $reached);
    }
  }

  /**
   * Remove options element's reached options.
   *
   * @param array $element
   *   An options element with limits.
   * @param array $reached
   *   An options element's reached options.
   */
  protected function removeOptionsElement(array &$element, array $reached) {
    $options =& $element['#options'];
    $this->removeOptionsElementRecursive($options, $reached);
  }

  /**
   * Remove options element's reached options.
   *
   * @param array $options
   *   An array options (and optgroups).
   * @param array $reached
   *   An options element's reached options.
   */
  protected function removeOptionsElementRecursive(array &$options, array $reached) {
    foreach ($options as $option_value => &$option_text) {
      if (is_array($option_text)) {
        $this->removeOptionsElementRecursive($option_text, $reached);
        if (empty($option_text)) {
          unset($options[$option_value]);
        }
      }
      elseif (isset($reached[$option_value])) {
        unset($options[$option_value]);
      }
    }
  }

  /**
   * Validate an options element with limit(s).
   *
   * @param array $element
   *   An options element with limits.
   * @param \Drupal\Core\Form\FormStateInterface $form_state
   *   The current state of the form.
   *
   * @internal
   *   This method should only called by
   *   OptionsLimitWebformHandler::validateElementLimit.
   */
  public function validateOptionsElement(array $element, FormStateInterface $form_state) {
    /** @var \Drupal\webform\WebformSubmissionForm $form_object */
    $form_object = $form_state->getFormObject();
    /** @var \Drupal\webform\WebformSubmissionInterface $webform_submission */
    $webform_submission = $form_object->getEntity();
    $this->setWebformSubmission($webform_submission);

    $element_key = $this->configuration['element_key'];

    // Get casting as array to support multiple options.
    $original_values = (array) $webform_submission->getElementOriginalData($element_key);
    $updated_values = (array) $form_state->getValue($element_key);
    if (empty($updated_values) || $updated_values === ['']) {
      return;
    }

    $limits = $this->getOptionsLimits($updated_values);
    foreach ($limits as $value => $limit) {
      // Do not apply option limit to any previously selected option value.
      if (in_array($value, $original_values)) {
        continue;
      }
      if ($limit['status'] === WebformOptionsLimitHandlerInterface::LIMIT_STATUS_NONE) {
        $message = $this->getElementLimitStatusMessage(WebformOptionsLimitHandlerInterface::LIMIT_STATUS_ERROR, $limit);
        $form_state->setError($element, $message);
      }
    }
  }

  /****************************************************************************/
  // Boolean element methods.
  /****************************************************************************/

  /**
   * Set a boolean element's default value.
   *
   * @param array $element
   *   A boolean element with limits.
   * @param array $limit
   *   A boolean element's limit information.
   * @param string $operation
   *   The form's current operation.
   */
  protected function setBooleanElementDefaultValue(array &$element, array $limit, $operation) {
    if ($operation === 'test') {
      if ($limit['status'] === WebformOptionsLimitHandlerInterface::LIMIT_STATUS_NONE) {
        unset($element['#default_value']);
      }
    }
    else {
      $element_key = $this->configuration['element_key'];
      $webform_submission = $this->getWebformSubmission();
      $original_value = $webform_submission->getElementOriginalData($element_key);
      if ($limit['status'] === WebformOptionsLimitHandlerInterface::LIMIT_STATUS_NONE && !$original_value) {
        unset($element['#default_value']);
      }
    }
  }

  /**
   * Alter a boolean element's.
   *
   * @param array $element
   *   An boolean element.
   * @param array $limit
   *   A webform boolean element's limit.
   */
  protected function alterBooleanElement(array &$element, array $limit) {
    // Set message.
    $message_display = $this->configuration['option_message_display'];
    if ($message_display !== WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_NONE) {
      $message = $this->getElementLimitStatusMessage($limit['status'], $limit);
      if ($message) {
        switch ($message_display) {
          case WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_LABEL:
            $t_args = [
              '@label' => $element['#title'],
              '@message' => $message,
            ];
            $element['#title'] = $this->t('@label @message', $t_args);
            break;

          case WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_DESCRIPTION:
            $element += ['#description' => ''];
            $element['#description'] .= ($element['#description']) ? '<br/>' . $message : $message;
            break;
        }
      }
    }

    // Disable or remove boolean element.
    $element_key = $this->configuration['element_key'];
    $webform_submission = $this->getWebformSubmission();
    $boolean_value = (boolean) ($webform_submission->getElementOriginalData($element_key) ?: FALSE);
    if ($limit['status'] === WebformOptionsLimitHandlerInterface::LIMIT_STATUS_NONE && !$boolean_value) {
      switch ($this->configuration['option_none_action']) {
        case WebformOptionsLimitHandlerInterface::LIMIT_ACTION_DISABLE:
          $element['#disabled'] = TRUE;
          break;

        case WebformOptionsLimitHandlerInterface::LIMIT_ACTION_REMOVE:
          $element['#access'] = FALSE;
          break;
      }

      // Display limit reached message.
      $this->setElementLimitReachedMessage($element);
    }
  }

  /**
   * Validate a boolean element with limit(s).
   *
   * Please note that this should never be called because disabled checkbox
   * elements do not post back any value. This code would be executed if
   * some one manually triggers for validation.
   *
   * @param array $element
   *   A boolean element with limits.
   * @param \Drupal\Core\Form\FormStateInterface $form_state
   *   The current state of the form.
   *
   * @internal
   *   This method should only called by
   *   OptionsLimitWebformHandler::validateElementLimit.
   */
  public function validateBooleanElement(array $element, FormStateInterface $form_state) {
    /** @var \Drupal\webform\WebformSubmissionForm $form_object */
    $form_object = $form_state->getFormObject();
    /** @var \Drupal\webform\WebformSubmissionInterface $webform_submission */
    $webform_submission = $form_object->getEntity();
    $this->setWebformSubmission($webform_submission);

    $element_key = $this->configuration['element_key'];

    $original_value = $webform_submission->getElementOriginalData($element_key);
    $updated_value = $form_state->getValue($element_key);
    if (empty($updated_value) || !empty($original_value)) {
      return;
    }

    $limit = $this->configuration['limit'];
    $total = $this->getBooleanTotal();
    if ($total >= $limit) {
      $limits = $this->getBooleanLimits();
      $message = $this->getElementLimitStatusMessage(WebformOptionsLimitHandlerInterface::LIMIT_STATUS_ERROR, reset($limits));
      $form_state->setError($element, $message);
    }
  }

  /****************************************************************************/
  // Form methods.
  /****************************************************************************/

  /**
   * {@inheritdoc}
   */
  public function submitForm(array &$form, FormStateInterface $form_state, WebformSubmissionInterface $webform_submission) {
    // Must invalidate webform cache tags.
    Cache::invalidateTags(['webform:' . $this->getWebform()->id()]);
  }

  /****************************************************************************/
  // Summary method.
  // @see \Drupal\webform_options_limit\Controller\WebformOptionsLimitController
  /****************************************************************************/

  /**
   * Build summary table.
   *
   * @return array
   *   A renderable containing the options limit summary table.
   */
  public function buildSummaryTable() {
    $element = $this->getElement();
    if (!$element) {
      return [];
    }

    if ($this->configuration['limit_user']) {
      return [];
    }

    $webform_element = $this->getWebformElement();

    $rows = [];
    $limits = $this->isOptionsElement()
      ? $this->getOptionsLimits()
      : $this->getBooleanLimits();
    foreach ($limits as $limit) {
      if ($limit['limit']) {
        $percentage = number_format(($limit['total'] / $limit['limit']) * 100) . '% ';
        $progress = [
          '#type' => 'html_tag',
          '#tag' => 'progress',
          '#attributes' => [
            'max' => $limit['limit'],
            'value' => $limit['total'],
          ],
        ];
      }
      else {
        $percentage = '';
        $progress = [];
      }

      $rows[] = [
        ['data' => $limit['label'], 'style' => 'font-weight: bold'],
        ['data' => $limit['limit'] ?: '∞', 'style' => 'text-align: right'],
        ['data' => $limit['limit'] ? $limit['remaining'] : '∞', 'style' => 'text-align: right'],
        ['data' => $limit['total'], 'style' => 'text-align: right'],
        ['data' => $progress, 'style' => 'text-align: center'],
        ['data' => $percentage, 'style' => 'text-align: right'],
      ];
    }

    return [
      'title' => [
        '#markup' => $webform_element->getLabel($element),
        '#prefix' => '<h2>',
        '#suffix' => '</h2>',
      ],
      'table' => [
        '#type' => 'table',
        '#header' => [
          '',
          ['data' => $this->t('Limit'), 'style' => 'text-align: right'],
          ['data' => $this->t('Remaining'), 'style' => 'text-align: right', 'class' => [RESPONSIVE_PRIORITY_LOW]],
          ['data' => $this->t('Total'), 'style' => 'text-align: right', 'class' => [RESPONSIVE_PRIORITY_LOW]],
          ['data' => $this->t('Progress'), 'style' => 'text-align: center', 'class' => [RESPONSIVE_PRIORITY_LOW]],
          '',
        ],
        '#rows' => $rows,
      ],
    ];
  }

  /****************************************************************************/
  // Element methods.
  /****************************************************************************/

  /**
   * Get element.
   *
   * @return array
   *   Selected element.
   */
  protected function getElement() {
    return $this->getWebform()->getElement($this->configuration['element_key']);
  }

  /**
   * Get selected webform element plugin.
   *
   * @return \Drupal\webform\Plugin\WebformElementInterface|null
   *   A webform element plugin instance.
   */
  protected function getWebformElement() {
    $element = $this->getElement();
    return ($element) ? $this->elementManager->getElementInstance($element) : NULL;
  }

  /**
   * Determine if options element.
   *
   * @return string
   *   TRUE if options element.
   */
  protected function isOptionsElement() {
    $webform_element = $this->getWebformElement();
    return ($webform_element instanceof OptionsBase);
  }

  /**
   * Determine if boolean element.
   *
   * @return string
   *   TRUE if boolean element.
   */
  protected function isBooleanElement() {
    $webform_element = $this->getWebformElement();
    return ($webform_element instanceof BooleanBase);
  }

  /**
   * Determine if table select  element.
   *
   * @return string
   *   TRUE if table select element.
   */
  protected function isTableSelectElement() {
    $webform_element = $this->getWebformElement();
    return ($webform_element instanceof TableSelect);
  }

  /**
   * Get selected webform element label.
   *
   * @return string
   *   A webform element label.
   */
  protected function getElementLabel() {
    $element = $this->getElement();
    $webform_element = $this->getWebformElement();
    return $webform_element->getLabel($element);
  }

  /**
   * Get key/value array of webform options or boolean elements.
   *
   * @return array
   *   A key/value array of webform options or boolean elements.
   */
  protected function getElements() {
    $webform = $this->getWebform();
    $elements = $webform->getElementsInitializedAndFlattened();

    $options = [];
    foreach ($elements as $element) {
      $webform_element = $this->elementManager->getElementInstance($element);
      $is_options_element = $webform_element->hasProperty('options');
      $is_entity_options_element = ($webform_element instanceof WebformElementEntityOptionsInterface);
      $is_boolean_element = ($webform_element instanceof BooleanBase);
      if ($is_options_element || $is_entity_options_element || $is_boolean_element) {
        $webform_key = $element['#webform_key'];
        $t_args = [
          '@title' => $webform_element->getAdminLabel($element),
          '@type' => $webform_element->getPluginLabel(),
        ];
        $options[$webform_key] = $this->t('@title (@type)', $t_args);
      }
    }

    // Exclude elements being used by other options limit handlers.
    $handlers = $webform->getHandlers();
    foreach ($handlers as $handler) {
      if ($handler instanceof WebformOptionsLimitHandlerInterface
        && $handler->getHandlerId() !== $this->getHandlerId()) {
        $element_key = $handler->getSetting('element_key');
        unset($options[$element_key]);
      }
    }

    return $options;
  }

  /**
   * Get table select elements.
   *
   * @return array
   *   An array containing table select elements.
   */
  protected function getTableSelectElements() {
    $webform = $this->getWebform();
    $elements = $webform->getElementsInitializedAndFlattened();

    $tableselect_elements = [];
    foreach ($elements as $element_key => $element) {
      $webform_element = $this->elementManager->getElementInstance($element);
      if ($webform_element instanceof TableSelect) {
        $tableselect_elements[$element_key] = $element_key;
      }
    }

    return $tableselect_elements;
  }

  /**
   * Get selected element's options.
   *
   * @return array
   *   A key/value array of options.
   */
  protected function getElementOptions() {
    $element = $this->getElement();

    // Set entity options.
    $webform_element = $this->getWebformElement();
    if ($webform_element instanceof WebformElementEntityOptionsInterface) {
      WebformEntityTrait::setOptions($element);
    }

    return ($element) ? OptGroup::flattenOptions($element['#options']) : [];
  }

  /****************************************************************************/
  // Limits methods.
  /****************************************************************************/

  /**
   * Get an associative array of options limits.
   *
   * @param array $values
   *   Optional array of values to get options limit.
   *
   * @return array
   *   An associative array of options limits keyed by option value and
   *   including the option's limit, total, remaining, and status.
   */
  protected function getOptionsLimits(array $values = []) {
    $default_limit = isset($this->configuration['limits'][WebformOptionsLimitHandlerInterface::DEFAULT_LIMIT])
      ? $this->configuration['limits'][WebformOptionsLimitHandlerInterface::DEFAULT_LIMIT]
      : NULL;

    $totals = $this->getOptionsTotals($values);

    $options = $this->getElementOptions();
    if ($values) {
      $options = array_intersect_key($options, array_combine($values, $values));
    }

    $limits = [];
    foreach ($options as $option_key => $option_label) {
      $limit = (isset($this->configuration['limits'][$option_key]))
        ? $this->configuration['limits'][$option_key]
        : $default_limit;
      $total = (isset($totals[$option_key])) ? $totals[$option_key] : 0;
      $limits[$option_key] = $this->getLimitInformation($option_label, $limit, $total);
    }
    return $limits;
  }

  /**
   * Get an associative array of boolean limits.
   *
   * @return array
   *   An associative array of boolean limits keyed by boolean key and
   *   includes the boolean's limit, total, remaining, and status.
   */
  protected function getBooleanLimits() {
    $element = $this->getElement();

    $key = $element['#webform_key'];
    $label = $element['#title'];

    $limit = $this->configuration['limit'];
    $total = $this->getBooleanTotal();

    return [$key => $this->getLimitInformation($label, $limit, $total)];
  }

  /**
   * Get limit information including label, limit, total, remaining, and status.
   *
   * @param string $label
   *   The element or option label.
   * @param int $limit
   *   The limit.
   * @param int $total
   *   The total.
   *
   * @return array
   *   The limit information including label, limit, total,
   *   remaining, and status.
   */
  protected function getLimitInformation($label, $limit, $total) {
    $total = $total ?: 0;
    $remaining = ($limit) ? $limit - $total : 0;

    if (empty($limit) && $limit !== 0) {
      $status = WebformOptionsLimitHandlerInterface::LIMIT_STATUS_UNLIMITED;
    }
    elseif ($remaining <= 0) {
      $status = WebformOptionsLimitHandlerInterface::LIMIT_STATUS_NONE;
    }
    elseif ($remaining === 1) {
      $status = WebformOptionsLimitHandlerInterface::LIMIT_STATUS_SINGLE;
    }
    else {
      $status = WebformOptionsLimitHandlerInterface::LIMIT_STATUS_MULTIPLE;
    }

    return [
      'label' => $label,
      'limit' => $limit,
      'total' => $total,
      'remaining' => $remaining,
      'status' => $status,
    ];
  }

  /**
   * Get value array of options reached.
   *
   * @param array $limits
   *   An associative array of options limits.
   *
   * @return array
   *   A value array of disabled options.
   */
  protected function getOptionsReached(array $limits) {
    $element_key = $this->configuration['element_key'];
    $webform_submission = $this->getWebformSubmission();
    $element_values = (array) $webform_submission->getElementOriginalData($element_key) ?: [];
    $reached = [];
    foreach ($limits as $option_value => $limit) {
      if ($element_values && in_array($option_value, $element_values)) {
        continue;
      }
      if ($limit['status'] === WebformOptionsLimitHandlerInterface::LIMIT_STATUS_NONE) {
        $reached[$option_value] = $option_value;
      }
    }
    return $reached;
  }

  /**
   * Get options submission totals for the current webform and source entity.
   *
   * @param array $values
   *   Optional array of values to get totals.
   *
   * @return array
   *   A key/value array of options totals.
   */
  protected function getOptionsTotals(array $values = []) {
    $query = $this->getTotalQuery();
    if (!$query) {
      return [];
    }

    $query->addExpression('COUNT(value)', 'total');
    $query->groupBy('value');
    if ($values) {
      $query->condition('sd.value', $values, 'IN');
    }
    return $query->execute()->fetchAllKeyed();
  }

  /**
   * Get boolean submission total for the current webform and source entity.
   *
   * @return int
   *   Boolean totals.
   */
  protected function getBooleanTotal() {
    $query = $this->getTotalQuery();
    if (!$query) {
      return NULL;
    }

    $query->condition('sd.value', '1');
    return $query->countQuery()->execute()->fetchField();
  }

  /**
   * Get base query for options and boolean limit totals.
   *
   * @return bool|\Drupal\Core\Database\Query\SelectInterface
   *   The base query for options and boolean limit totals.
   */
  protected function getTotalQuery() {
    $webform = $this->getWebform();

    /** @var \Drupal\Core\Database\StatementInterface $result */
    $query = $this->database->select('webform_submission', 's');
    $query->join('webform_submission_data', 'sd', 's.sid = sd.sid');
    $query->fields('sd', ['value']);
    $query->condition('sd.name', $this->configuration['element_key']);
    $query->condition('sd.webform_id', $webform->id());

    // Limit by source entity.
    if ($this->configuration['limit_source_entity']) {
      $source_entity = $this->getSourceEntity();
      if ($source_entity) {
        $query->condition('s.entity_type', $source_entity->getEntityTypeId());
        $query->condition('s.entity_id', $source_entity->id());
      }
      else {
        $query->isNull('s.entity_type');
        $query->isNull('s.entity_id');
      }
    }

    // Limit by authenticated or anonymous user.
    if ($this->configuration['limit_user']) {
      if ($this->currentUser->isAuthenticated()) {
        $query->condition('s.uid', $this->currentUser->id());
      }
      else {
        $sids = $this->submissionStorage->getAnonymousSubmissionIds($this->currentUser);
        if ($sids) {
          $query->condition('s.sid', $sids, 'IN');
          $query->condition('s.uid', 0);
        }
        else {
          return FALSE;
        }
      }
    }
    return $query;
  }

  /****************************************************************************/
  // Labels and messages methods.
  /****************************************************************************/

  /**
   * Get an options or boolean element's limit status message.
   *
   * @param string $type
   *   Type of message.
   * @param array $limit
   *   Associative array containing limit, total, remaining, and label.
   *
   * @return \Drupal\Component\Render\FormattableMarkup|string
   *   A limit status message.
   */
  protected function getElementLimitStatusMessage($type, array $limit) {
    $message = $this->configuration['option_' . $type . '_message'];
    if (!$message) {
      return '';
    }

    return new FormattableMarkup($message, [
      '@name' => $this->getElementLabel(),
      '@label' => $limit['label'],
      '@limit' => $limit['limit'],
      '@total' => $limit['total'],
      '@remaining' => $limit['remaining'],
    ]);
  }

  /**
   * Get option limit label.
   *
   * @param string $label
   *   An option's label.
   * @param array $limit
   *   The option's limit information.
   *
   * @return \Drupal\Core\StringTranslation\TranslatableMarkup|string
   *   An option's limit label.
   */
  protected function getOptionsLimitLabel($label, array $limit) {
    $message_display = $this->configuration['option_message_display'];
    if ($message_display === WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_NONE) {
      return $label;
    }

    $message = $this->getElementLimitStatusMessage($limit['status'], $limit);
    if (!$message) {
      return $label;
    }

    switch ($message_display) {
      case WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_LABEL:
        $t_args = ['@label' => $label, '@message' => $message];
        return $this->t('@label @message', $t_args);

      case WebformOptionsLimitHandlerInterface::MESSAGE_DISPLAY_DESCRIPTION:
        return $label
          . (!WebformOptionsHelper::hasOptionDescription($label) ? WebformOptionsHelper::DESCRIPTION_DELIMITER : '')
          . $message;
    }
  }

}
