block.php

<?php

/**
 * @file
 * Contains \Drupal\system\Plugin\Block\SystemBrandingBlock.
 */

namespace Drupal\system\Plugin\Block;

use Drupal\block\BlockBase;
use Drupal\Core\Config\ConfigFactoryInterface;
use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
use Drupal\Core\Routing\UrlGeneratorInterface;
use Drupal\Component\Utility\Xss;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\HttpFoundation\Request;

/**
 * Provides a block to display 'Site branding' elements.
 *
 * @Block(
 *   id = "system_branding_block",
 *   admin_label = @Translation("Site branding")
 * )
 */
class SystemBrandingBlock extends BlockBase implements ContainerFactoryPluginInterface {

  /**
   * The URL generator.
   *
   * @var \Drupal\Core\Routing\UrlGeneratorInterface
   */
  protected $urlGenerator;

  /**
   * Stores the configuration factory.
   *
   * @var \Drupal\Core\Config\ConfigFactoryInterface
   */
  protected $configFactory;
  
  /**
   * The current request.
   * 
   * @var \Symfony\Component\HttpFoundation\Request
   */
  protected $request;

  /**
   * Creates a SystemBrandingBlock instance.
   *
   * @param array $configuration
   *   A configuration array containing information about the plugin instance.
   * @param string $plugin_id
   *   The plugin_id for the plugin instance.
   * @param array $plugin_definition
   *   The plugin implementation definition.
   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
   *   The factory for configuration objects.
   * @param \Drupal\Core\Routing\UrlGeneratorInterface $url_generator
   *   The url generator service.
   * @param \Symfony\Component\HttpFoundation\Request
   *   The current request.
   */
  public function __construct(array $configuration, $plugin_id, array $plugin_definition, ConfigFactoryInterface $config_factory, UrlGeneratorInterface $url_generator, Request $request) {
    parent::__construct($configuration, $plugin_id, $plugin_definition);
    $this->configFactory = $config_factory;
    $this->urlGenerator = $url_generator;
    $this->request = $request;
  }

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

  /**
   * Generates a URL or path for a specific route based on the given parameters.
   *
   * @see \Drupal\Core\Routing\UrlGeneratorInterface::generateFromRoute() for
   *   details on the arguments, usage, and possible exceptions.
   *
   * @return string
   *   The generated URL for the given route.
   */
  public function url($route_name, $route_parameters = array(), $options = array()) {
    return $this->urlGenerator->generateFromRoute($route_name, $route_parameters, $options);
  }

  /**
   * {@inheritdoc}
   */
  public function defaultConfiguration() {
    return array(
      'use_site_logo' => TRUE,
      'use_site_name' => TRUE,
      'use_site_slogan' => TRUE,
      'label_display' => FALSE,
    );
  }

  /**
   * {@inheritdoc}
   */
  public function blockForm($form, &$form_state) {
    $form['block_branding'] = array(
      '#type' => 'details',
      '#title' => $this->t('Toggle branding elements'),
      '#description' => $this->t('Choose which branding elements you want to show in this block instance.'),
      '#collapsed' => FALSE,
      '#collapsible' => FALSE,
    );
    $form['block_branding']['use_site_logo'] = array(
      '#type' => 'checkbox',
      '#title' => $this->t('Site logo'),
      '#description' => $this->t('Defined on the <a href="@appearance">Appearance</a> or theme settings page.', array('@appearance' => $this->url('system.themes_page'))),
      '#default_value' => $this->configuration['use_site_logo'],
    );

    $form['block_branding']['use_site_name'] = array(
      '#type' => 'checkbox',
      '#title' => $this->t('Site name'),
      '#description' => $this->t('Defined on the <a href="@information">Site Information</a> page.', array('@information' => $this->url('system.site_information_settings'))),
      '#default_value' => $this->configuration['use_site_name'],
    );
    $form['block_branding']['use_site_slogan'] = array(
      '#type' => 'checkbox',
      '#title' => $this->t('Site slogan'),
      '#description' => $this->t('Defined in Site information settings.'),
      '#default_value' => $this->configuration['use_site_slogan'],
    );
    // Get the theme.
    $theme = $this->request->attributes->get('theme');
    return $form;
  }

  /**
   * {@inheritdoc}
   */
  public function blockSubmit($form, &$form_state) {
    $this->configuration['use_site_logo'] = $form_state['values']['block_branding']['use_site_logo'];
    $this->configuration['use_site_name'] = $form_state['values']['block_branding']['use_site_name'];
    $this->configuration['use_site_slogan'] = $form_state['values']['block_branding']['use_site_slogan'];
  }

  /**
   * {@inheritdoc}
   */
  public function build() {
    $build = array();
    $site_config = $this->configFactory->get('system.site');
    $build['#theme'] = 'branding';

    $build['#use_site_logo'] = $this->configuration['use_site_logo'];
    $build['#site_logo'] = theme_get_setting('logo');

    $build['#use_site_name'] = $this->configuration['use_site_name'];
    $build['#site_name'] = $site_config->get('name');

    $build['#use_site_slogan'] = $this->configuration['use_site_slogan'];
    $build['#site_slogan'] = Xss::filterAdmin($site_config->get('slogan'));

    return $build;
  }

}