<?php

namespace Drupal\form_test\Plugin\Block;

use Drupal\Core\Block\BlockBase;
use Drupal\Core\Form\FormBuilderInterface;
use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
use Symfony\Component\DependencyInjection\ContainerInterface;

/**
 * Provides a block containing a simple redirect form.
 *
 * @see \Drupal\form_test\Form\RedirectBlockForm
 *
 * @Block(
 *   id = "redirect_form_block",
 *   admin_label = @Translation("Redirecting form"),
 *   category = @Translation("Forms")
 * )
 */
class RedirectFormBlock extends BlockBase implements ContainerFactoryPluginInterface {

  /**
   * The form builder.
   *
   * @var \Drupal\Core\Form\FormBuilderInterface
   */
  protected $formBuilder;

  /**
   * Constructs a new RedirectFormBlock.
   *
   * @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\Core\Form\FormBuilderInterface $form_builder
   *   The form builder.
   */
  public function __construct(array $configuration, $plugin_id, $plugin_definition, FormBuilderInterface $form_builder) {
    parent::__construct($configuration, $plugin_id, $plugin_definition);

    $this->formBuilder = $form_builder;
  }

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

  /**
   * {@inheritdoc}
   */
  public function build() {
    return $this->formBuilder->getForm('Drupal\form_test\Form\RedirectBlockForm');
  }

  /**
   * {@inheritdoc}
   *
   * @todo Make cacheable once https://www.drupal.org/node/2351015 lands.
   */
  public function getCacheMaxAge() {
    return 0;
  }

}