<?php
  
  /*
   * This file is part of the Symfony package.
   *
   * (c) Fabien Potencier <fabien@symfony.com>
   *
   * For the full copyright and license information, please view the LICENSE
   * file that was distributed with this source code.
   */
  
  namespace Symfony\Component\Translation\Loader;
  
  use Symfony\Component\Translation\MessageCatalogue;
  
  /**
   * ArrayLoader loads translations from a PHP array.
   *
   * @author Fabien Potencier <fabien@symfony.com>
   */
  class ArrayLoader implements LoaderInterface
  {
      /**
       * {@inheritdoc}
       */
      public function load($resource, string $locale, string $domain = 'messages')
      {
          $resource = $this->flatten($resource);
          $catalogue = new MessageCatalogue($locale);
          $catalogue->add($resource, $domain);
  
          return $catalogue;
      }
  
      /**
       * Flattens an nested array of translations.
       *
       * The scheme used is:
       *   'key' => ['key2' => ['key3' => 'value']]
       * Becomes:
       *   'key.key2.key3' => 'value'
       */
      private function flatten(array $messages): array
      {
          $result = [];
          foreach ($messages as $key => $value) {
              if (\is_array($value)) {
                  foreach ($this->flatten($value) as $k => $v) {
                      if (null !== $v) {
                          $result[$key.'.'.$k] = $v;
                      }
                  }
              } elseif (null !== $value) {
                  $result[$key] = $value;
              }
          }
  
          return $result;
      }
  }