<?php

/**
 * @file
 * Contains \Drupal\migrate\Plugin\migrate\process\MachineName.
 */

namespace Drupal\migrate\Plugin\migrate\process;

use Drupal\Component\Transliteration\TransliterationInterface;
use Drupal\Core\Language\LanguageInterface;
use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
use Drupal\migrate\ProcessPluginBase;
use Drupal\migrate\MigrateExecutableInterface;
use Drupal\migrate\Row;
use Symfony\Component\DependencyInjection\ContainerInterface;

/**
 * This plugin creates a machine name.
 *
 * The current value gets transliterated, non-alphanumeric characters removed
 * and replaced by an underscore and multiple underscores are collapsed into
 * one.
 *
 * @MigrateProcessPlugin(
 *   id = "machine_name"
 * )
 */
class MachineName extends ProcessPluginBase implements ContainerFactoryPluginInterface {

  /**
   * The transliteration service.
   *
   * @var \Drupal\Component\Transliteration\TransliterationInterface
   */
  protected $transliteration;

  /**
   * Constructs a MachineName plugin.
   *
   * @param array $configuration
   *   The plugin configuration.
   * @param string $plugin_id
   *   The plugin ID.
   * @param mixed $plugin_definition
   *   The plugin definition.
   * @param \Drupal\Component\Transliteration\TransliterationInterface $transliteration
   *   The transliteration service.
   */
  public function __construct(array $configuration, $plugin_id, $plugin_definition, TransliterationInterface $transliteration) {
    parent::__construct($configuration, $plugin_id, $plugin_definition);
    $this->transliteration = $transliteration;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
    return new static(
      $configuration,
      $plugin_id,
      $plugin_definition,
      $container->get('transliteration')
    );
  }

  /**
   * {@inheritdoc}
   */
  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
    $new_value = $this->transliteration->transliterate($value, LanguageInterface::LANGCODE_DEFAULT, '_');
    $new_value = strtolower($new_value);
    $new_value = preg_replace('/[^a-z0-9_]+/', '_', $new_value);
    return preg_replace('/_+/', '_', $new_value);
  }

}
