<?php

namespace Drupal\premium_maps\Element;

use Drupal\Core\Render\Element;
use Drupal\Core\Render\Element\RenderElement;

/**
 * Defines a render element for builder a map.
 *
 * @RenderElement("map")
 *
 * @internal
 *   Plugin classes are internal
 */
class Map extends RenderElement {

  /**
   * Returns the element properties for this element.
   *
   * @return array
   *   An array of element properties. See
   *   \Drupal\Core\Render\ElementInfoManagerInterface::getInfo() for
   *   documentation of the standard properties of all elements, and the
   *   return value format.
   */
  public function getInfo() {
    $class = get_class($this);
    return [
      '#theme' => 'map',
      '#pre_render' => [
//        [$class, 'onRenderFilters'],
//        [$class, 'onRenderMap'],
      ],
      '#attached' => [
        'library' => [
          'premium_maps/google_map',
        ],
      ],
    ];
  }

  /**
   * Pre render function for the map.
   *
   * @param array $element
   *   The element.
   */
  public function onRenderMap($element) {

    if (!empty($element)) {
      $markers = Element::children($element['markers']);
      foreach ($markers as $marker) {
        $element['#attached']['drupalSettings']['map'] = $marker;
      }
    }
  }

  public function onRenderFilters($element) {

  }

}