social_media_links.module

<?php

/**
 * @file
 * Allows to add a block with the links to various social media platforms.
 */

use Drupal\Core\Routing\RouteMatchInterface;

/**
 * Implements hook_theme().
 */
function social_media_links_theme($existing, $type, $theme, $path) {
  return [
    'social_media_links_platforms' => [
      'variables' => [
        'platforms' => [],
        'appearance' => [],
      ],
    ],
  ];
}

/**
 * Implements hook_theme_suggestions_HOOK() for "social_media_links_platforms".
 */
function social_media_links_theme_suggestions_social_media_links_platforms(array $variables) {
  $suggestions = [];

  // If there is a custom suggestion add it to our base suggestion.
  if (!empty($variables['appearance']['suggestion'])) {
    $suggestions[] = 'social_media_links_platforms__' . $variables['appearance']['suggestion'];
  }

  return $suggestions;
}

/**
 * Implements hook_preprocess_HOOK() for block.html.twig.
 */
function social_media_links_preprocess_block(&$variables) {
  if ($variables['plugin_id'] === 'social_media_links_block') {
    // Ensure that the css class "block-social-media-links" always exist,
    // no mather was theme is used. Because our styles use this class.
    $variables['attributes']['class'][] = 'block-social-media-links';
  }
}

/**
 * Implements hook_help().
 */
function social_media_links_help($route_name, RouteMatchInterface $route_match) {
  switch ($route_name) {
    case 'help.page.social_media_links':
      $output = '';
      $output .= '<h3>' . t('About') . '</h3>';
      $output .= '<p>' . t('The modules provides a configurable block that display links (icons) to your profiles on various popular networking sites.') . '</p>';
      $output .= '<h3>' . t('Installation') . '</h3>';
      $output .= '<p><label>1.&nbsp;</label>' . t('Install as usual, see <a href=":documentation">installing contributed modules</a> for further information.', [':documentation' => 'https://www.drupal.org/docs/8/extending-drupal-8/installing-contributed-modules-find-import-enable-configure']) . '</p>';
      $output .= '<p><label>2.&nbsp;</label>' . t('The module has no special configuration. All settings are available in the block settings: /admin/structure/block.') . '</p>';
      $output .= '<h3>' . t('Included icon sets') . '</h3>';
      $output .= '<p>' . t('The module contains a icon set, that the module is ready for use immediately after the installation.') . '</p>';
      return $output;
  }
}

/**
 * Attaching css file.
 */
function social_media_links_page_attachments(array &$attachments) {
  $attachments['#attached']['library'][] = 'social_media_links/social_media_links.theme';
}