class Raw

class Raw extends ArgumentDefaultPluginBase implements CacheableDependencyInterface {
    
    /**
     * The alias manager.
     *
     * @var \Drupal\path_alias\AliasManagerInterface
     */
    protected $aliasManager;
    
    /**
     * The current path.
     *
     * @var \Drupal\Core\Path\CurrentPathStack
     */
    protected $currentPath;
    
    /**
     * Constructs a Raw object.
     *
     * @param array $configuration
     *   A configuration array containing information about the plugin instance.
     * @param string $plugin_id
     *   The plugin ID for the plugin instance.
     * @param mixed $plugin_definition
     *   The plugin implementation definition.
     * @param \Drupal\path_alias\AliasManagerInterface $alias_manager
     *   The alias manager.
     * @param \Drupal\Core\Path\CurrentPathStack $current_path
     *   The current path.
     */
    public function __construct(array $configuration, $plugin_id, $plugin_definition, AliasManagerInterface $alias_manager, CurrentPathStack $current_path) {
        parent::__construct($configuration, $plugin_id, $plugin_definition);
        $this->aliasManager = $alias_manager;
        $this->currentPath = $current_path;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
        return new static($configuration, $plugin_id, $plugin_definition, $container->get('path_alias.manager'), $container->get('path.current'));
    }
    
    /**
     * {@inheritdoc}
     */
    protected function defineOptions() {
        $options = parent::defineOptions();
        $options['index'] = [
            'default' => '',
        ];
        $options['use_alias'] = [
            'default' => FALSE,
        ];
        return $options;
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildOptionsForm(&$form, FormStateInterface $form_state) {
        parent::buildOptionsForm($form, $form_state);
        $form['index'] = [
            '#type' => 'select',
            '#title' => $this->t('Path component'),
            '#default_value' => $this->options['index'],
            // range(1, 10) returns an array with:
            // - keys that count from 0 to match PHP array keys from explode().
            // - values that count from 1 for display to humans.
'#options' => range(1, 10),
            '#description' => $this->t('The numbering starts from 1, e.g. on the page admin/structure/types, the 3rd path component is "types".'),
        ];
        $form['use_alias'] = [
            '#type' => 'checkbox',
            '#title' => $this->t('Use path alias'),
            '#default_value' => $this->options['use_alias'],
            '#description' => $this->t('Use path alias instead of internal path.'),
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    public function getArgument() {
        // Don't trim the leading slash since getAliasByPath() requires it.
        $path = rtrim($this->currentPath
            ->getPath($this->view
            ->getRequest()), '/');
        if ($this->options['use_alias']) {
            $path = $this->aliasManager
                ->getAliasByPath($path);
        }
        $args = explode('/', $path);
        // Drop the empty first element created by the leading slash since the path
        // component index doesn't take it into account.
        array_shift($args);
        if (isset($args[$this->options['index']])) {
            return $args[$this->options['index']];
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function getCacheMaxAge() {
        return Cache::PERMANENT;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getCacheContexts() {
        return [
            'url',
        ];
    }

}