<?php

/**
 * @file
 * Contains install and update functions for Block.
 */

use Drupal\Core\Cache\Cache;

/**
 * Implements hook_install().
 */
function block_install() {
  // Because the Block module upon installation unconditionally overrides all
  // HTML output by selecting a different page display variant, we must
  // invalidate all cached HTML output.
  Cache::invalidateTags(['rendered']);
}

/**
 * @addtogroup updates-8.0.0-beta
 * @{
 */

/**
 * Update block visibility context mapping.
 */
function block_update_8001() {
  // This update function updates blocks for the change from
  // https://www.drupal.org/node/2354889.

  // Core visibility context plugins are updated automatically; blocks with
  // unknown plugins are disabled and their previous visibility settings are
  // saved in key value storage; see change record
  // https://www.drupal.org/node/2527840 for more explanation.

  // These are all the contexts that Drupal core provides.
  $context_service_id_map = [
    'node.node' => '@node.node_route_context:node',
    'user.current_user' => '@user.current_user_context:current_user',
  ];

  foreach (array_keys(\Drupal::languageManager()->getDefinedLanguageTypesInfo()) as $language_type_id) {
    $context_service_id_map['language.' . $language_type_id] = '@language.current_language_context:' . $language_type_id;
  }

  // Contributed modules should leverage hook_update_dependencies() in order to
  // be executed before block_update_8002(), so they can update their context
  // mappings, if wanted.
  $config_factory = \Drupal::configFactory();
  $backup_values = $update_backup = [];

  foreach ($config_factory->listAll('block.block.') as $block_config_name) {
    $block = $config_factory->getEditable($block_config_name);
    if ($visibility = $block->get('visibility')) {
      foreach ($visibility as $condition_plugin_id => &$condition) {
        foreach ($condition['context_mapping'] as $key => $context) {
          if (!isset($context_service_id_map[$context])) {
            // Remove the visibility condition for unknown context mapping
            // entries, so the update process itself runs through and users can
            // fix their block placements manually OR alternatively contributed
            // modules can run their own update functions to update mappings
            // that they provide.
            $backup_values[$context][] = $condition_plugin_id;
            unset($visibility[$condition_plugin_id]);
            continue;
          }
          // Replace the context ID based on the defined mapping.
          $condition['context_mapping'][$key] = $context_service_id_map[$context];
        }
      }
      $block->set('visibility', $visibility);

      if ($backup_values) {
        // We not only store the missing context mappings but also the previous
        // block status, in order to allow contributed and custom modules to do
        // their own updates.
        $update_backup[$block->get('id')] = [
          'missing_context_ids' => $backup_values,
          'status' => $block->get('status')
        ];
      }
    }

    // Mark the resulting configuration as trusted data. This avoids issues with
    // future schema changes.
    $block->save(TRUE);
  }

  if ($update_backup) {
    \Drupal::keyValue('update_backup')->set('block_update_8001', $update_backup);
  }

  return t('Block context IDs updated.');
}

/**
 * Disable all blocks with missing context IDs in block_update_8001().
 */
function block_update_8002() {
  $block_update_8001 = \Drupal::keyValue('update_backup')->get('block_update_8001', []);

  $block_ids = array_keys($block_update_8001);
  $config_factory = \Drupal::configFactory();
  /** @var \Drupal\Core\Config\Config[] $blocks */
  $blocks = [];
  foreach ($block_ids as $block_id) {
    $blocks[$block_id] = $block = $config_factory->getEditable('block.block.' . $block_id);
    // This block will have an invalid context mapping service and must be
    // disabled in order to prevent information disclosure.

    // Disable currently enabled blocks.
    if ($block_update_8001[$block_id]['status']) {
      $block->set('status', FALSE);
      $block->save(TRUE);
    }
  }

  // Provides a list of plugin labels, keyed by plugin ID.
  $condition_plugin_id_label_map = array_column(\Drupal::service('plugin.manager.condition')->getDefinitions(), 'label', 'id');

  // Override with the UI labels we are aware of. Sadly they are not machine
  // accessible, see
  // \Drupal\node\Plugin\Condition\NodeType::buildConfigurationForm().
  $condition_plugin_id_label_map['node_type'] = t('Content types');
  $condition_plugin_id_label_map['request_path'] = t('Pages');
  $condition_plugin_id_label_map['user_role'] = t('Roles');

  if (count($block_ids) > 0) {
    $message = t('Encountered an unknown context mapping key coming probably from a contributed or custom module: One or more mappings could not be updated. Please manually review your visibility settings for the following blocks, which are disabled now:');
    $message .= '<ul>';
    foreach ($blocks as $disabled_block_id => $disabled_block) {
      $message .= '<li>' . t('@label (Visibility: @plugin_ids)', array(
            '@label' => $disabled_block->get('settings.label'),
            '@plugin_ids' => implode(', ', array_intersect_key($condition_plugin_id_label_map, array_flip(array_keys($block_update_8001[$disabled_block_id]['missing_context_ids']))))
          )) . '</li>';
    }
    $message .= '</ul>';

    return $message;
  }
}

/**
 * @} End of "addtogroup updates-8.0.0-beta".
 */