CshsGroupByRootFormatter.php in Client-side Hierarchical Select 8.3

Namespace

Drupal\cshs\Plugin\Field\FieldFormatter

File

src/Plugin/Field/FieldFormatter/CshsGroupByRootFormatter.php

<?php

namespace Drupal\cshs\Plugin\Field\FieldFormatter;

use Drupal\Core\Field\FieldItemListInterface;
use Drupal\Core\Form\FormStateInterface;

/**
 * Plugin implementation of the "Group by root" formatter.
 *
 * @FieldFormatter(
 *   id = "cshs_group_by_root",
 *   label = @Translation("Hierarchy grouped by root"),
 *   description = @Translation("Display the hierarchy of the taxonomy term grouped by root."),
 *   field_types = {
 *     "entity_reference",
 *   },
 * )
 *
 * @example
 * The result of a multivalued selection, grouped by root.
 * @code
 * Given:
 *   field_tags.0: a, b, c
 *   field_tags.1: a, b1
 *   field_tags.2: a, b, c, d
 *   field_tags.3: a1, b1, c1
 *   field_tags.4: a1, b1, c1, d1
 *
 * Result (reverse=FALSE):
 *   a
 *     - b
 *     - c
 *     - b1
 *     - d
 *   a1
 *     - b1
 *     - c1
 *     - d1
 *
 * Result (reverse=TRUE):
 *   c
 *     - b
 *     - a
 *   b1
 *     - a
 *   d
 *     - c
 *     - b
 *     - a
 *   c1
 *     - b1
 *     - a1
 *   d1
 *     - c1
 *     - b1
 *     - a1
 * @code
 */
class CshsGroupByRootFormatter extends CshsFormatterBase {

  /**
   * The option to disable sorting.
   */
  public const SORT_NONE = 'none';

  /**
   * The option to sort children descendingly.
   */
  public const SORT_DESC = 'desc';

  /**
   * The option to sort children ascendingly.
   */
  public const SORT_ASC = 'asc';

  /**
   * The list of all available sorting variants.
   */
  protected const SORT_OPTIONS = [
    self::SORT_NONE => 'None',
    self::SORT_DESC => 'Descending',
    self::SORT_ASC => 'Ascending',
  ];

  /**
   * The list of PHP functions that sort an array by key.
   *
   * NOTES:
   *   - the function must modify the argument by reference;
   *   - the function argument must be an associative array because sorting
   *     happens by keys.
   *
   * @see \krsort()
   * @see \ksort()
   */
  protected const SORT_FUNCTIONS = [
    self::SORT_DESC => '\\krsort',
    self::SORT_ASC => '\\ksort',
  ];

  /**
   * {@inheritdoc}
   */
  public static function defaultSettings() : array {
    $settings = parent::defaultSettings();
    $settings['sort'] = static::SORT_NONE;
    $settings['depth'] = 0;
    return $settings;
  }

  /**
   * {@inheritdoc}
   */
  public function settingsForm(array $form, FormStateInterface $form_state) : array {
    $element = parent::settingsForm($form, $form_state);
    $element['sort'] = [
      '#type' => 'select',
      '#title' => $this
        ->t('Sorting'),
      '#options' => \array_map([
        $this,
        't',
      ], static::SORT_OPTIONS),
      '#default_value' => $this
        ->getSetting('sort'),
    ];
    $element['depth'] = [
      '#type' => 'number',
      '#min' => 0,
      '#title' => $this
        ->t('Depth'),
      '#description' => $this
        ->t('The maximum hierarchy depth. Use 0 to not limit or 1 to display just the root term (or the last if reverse order selected).'),
      '#default_value' => $this
        ->getSetting('depth'),
    ];
    return $element;
  }

  /**
   * {@inheritdoc}
   */
  public function settingsSummary() : array {
    $summary = parent::settingsSummary();
    $summary[] = $this
      ->t('Sorting: @value', [
      '@value' => static::SORT_OPTIONS[$this
        ->getSetting('sort')],
    ]);
    $summary[] = $this
      ->t('Depth: @value', [
      '@value' => $this
        ->getSetting('depth') ?: $this
        ->t('Unlimited'),
    ]);
    return $summary;
  }

  /**
   * {@inheritdoc}
   */
  public function viewElements(FieldItemListInterface $items, $langcode) : array {
    $depth = $this
      ->getSetting('depth');
    $linked = $this
      ->getSetting('linked');
    $reverse = $this
      ->getSetting('reverse');
    $elements = [];
    foreach ($this
      ->getEntitiesToView($items, $langcode) as $term) {
      $tree = $this
        ->getTermParents($term, !$reverse);
      if ($depth > 0) {

        // @todo This is not an optimal solution as we may load lots of entities that won't be used.
        $tree = \array_slice($tree, 0, $depth, TRUE);
      }
      $labels = $this
        ->getTermsLabels($tree, $linked);
      $root = \array_shift($tree);
      $root_id = $root
        ->id();
      $root_label = \array_shift($labels);
      if (!isset($elements[$root_id])) {
        $elements[$root_id] = [
          '#theme' => 'cshs_term_group',
          '#id' => $root_id,
          '#title' => $root_label,
          '#terms' => [],
        ];
      }

      // Replace calls to `\array_merge()` and `\array_unique()` by the loop.
      foreach ($labels as $i => $label) {
        $unique_key = (string) $tree[$i]
          ->label();
        if (!isset($elements[$root_id]['#terms'][$unique_key])) {
          $elements[$root_id]['#terms'][$unique_key] = [
            'id' => $tree[$i]
              ->id(),
            'label' => $label,
            'parent' => $tree[$i]->parent->target_id,
          ];
        }
      }
    }
    if ($sort_function = static::SORT_FUNCTIONS[$this
      ->getSetting('sort')] ?? NULL) {
      foreach ($elements as $root_id => $element) {
        $sort_function($elements[$root_id]['#terms']);
      }
    }
    return $elements;
  }

}

Classes

Name	Description
CshsGroupByRootFormatter	Plugin implementation of the "Group by root" formatter.