class ConfigSync

class ConfigSync extends FormBase {
    
    /**
     * Constructs the object.
     *
     * @param \Drupal\Core\Config\StorageInterface $syncStorage
     *   The source storage.
     * @param \Drupal\Core\Config\StorageInterface $activeStorage
     *   The target storage.
     * @param \Drupal\Core\Config\StorageInterface $snapshotStorage
     *   The snapshot storage.
     * @param \Drupal\Core\Lock\LockBackendInterface $lock
     *   The lock object.
     * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $eventDispatcher
     *   Event dispatcher.
     * @param \Drupal\Core\Config\ConfigManagerInterface $configManager
     *   Configuration manager.
     * @param \Drupal\Core\Config\TypedConfigManagerInterface $typedConfigManager
     *   The typed configuration manager.
     * @param \Drupal\Core\Extension\ModuleHandlerInterface $moduleHandler
     *   The module handler.
     * @param \Drupal\Core\Extension\ModuleInstallerInterface $moduleInstaller
     *   The module installer.
     * @param \Drupal\Core\Extension\ThemeHandlerInterface $themeHandler
     *   The theme handler.
     * @param \Drupal\Core\Render\RendererInterface $renderer
     *   The renderer.
     * @param \Drupal\Core\Extension\ModuleExtensionList $moduleExtensionList
     *   The module extension list
     * @param \Drupal\Core\Config\ImportStorageTransformer $importTransformer
     *   The import transformer service.
     * @param \Drupal\Core\Extension\ThemeExtensionList $themeExtensionList
     *   The theme extension list.
     */
    public function __construct(StorageInterface $syncStorage, StorageInterface $activeStorage, StorageInterface $snapshotStorage, LockBackendInterface $lock, EventDispatcherInterface $eventDispatcher, ConfigManagerInterface $configManager, TypedConfigManagerInterface $typedConfigManager, ModuleHandlerInterface $moduleHandler, ModuleInstallerInterface $moduleInstaller, ThemeHandlerInterface $themeHandler, RendererInterface $renderer, ModuleExtensionList $moduleExtensionList, ImportStorageTransformer $importTransformer, ThemeExtensionList $themeExtensionList) {
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container) {
        return new static($container->get('config.storage.sync'), $container->get('config.storage'), $container->get('config.storage.snapshot'), $container->get('lock.persistent'), $container->get('event_dispatcher'), $container->get('config.manager'), $container->get('config.typed'), $container->get('module_handler'), $container->get('module_installer'), $container->get('theme_handler'), $container->get('renderer'), $container->get('extension.list.module'), $container->get('config.import_transformer'), $container->get('extension.list.theme'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function getFormId() {
        return 'config_admin_import_form';
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildForm(array $form, FormStateInterface $form_state) {
        $form['actions'] = [
            '#type' => 'actions',
        ];
        $form['actions']['submit'] = [
            '#type' => 'submit',
            '#value' => $this->t('Import all'),
        ];
        $syncStorage = $this->importTransformer
            ->transform($this->syncStorage);
        $source_list = $syncStorage->listAll();
        $storage_comparer = new StorageComparer($syncStorage, $this->activeStorage);
        $storage_comparer->createChangelist();
        if (empty($source_list) || !$storage_comparer->hasChanges()) {
            $form['no_changes'] = [
                '#type' => 'table',
                '#header' => [
                    $this->t('Name'),
                    $this->t('Operations'),
                ],
                '#rows' => [],
                '#empty' => empty($source_list) ? $this->t('There is no staged configuration.') : $this->t('The staged configuration is identical to the active configuration.'),
            ];
            $form['actions']['#access'] = FALSE;
            return $form;
        }
        elseif (!$storage_comparer->validateSiteUuid()) {
            $this->messenger()
                ->addError($this->t('The staged configuration cannot be imported, because it originates from a different site than this site. You can only synchronize configuration between cloned instances of this site.'));
            $form['actions']['#access'] = FALSE;
            return $form;
        }
        // A list of changes will be displayed, so check if the user should be
        // warned of potential losses to configuration.
        if ($this->snapshotStorage
            ->exists('core.extension')) {
            $snapshot_comparer = new StorageComparer($this->activeStorage, $this->snapshotStorage);
            $snapshot_comparer->createChangelist();
            if (!$form_state->getUserInput() && $snapshot_comparer->hasChanges()) {
                $change_list = [];
                foreach ($snapshot_comparer->getAllCollectionNames() as $collection) {
                    foreach ($snapshot_comparer->getChangelist(NULL, $collection) as $config_names) {
                        if (empty($config_names)) {
                            continue;
                        }
                        foreach ($config_names as $config_name) {
                            $change_list[] = $config_name;
                        }
                    }
                }
                sort($change_list);
                $message = [
                    [
                        '#markup' => $this->t('The following items in your active configuration have changes since the last import that may be lost on the next import.'),
                    ],
                    [
                        '#theme' => 'item_list',
                        '#items' => $change_list,
                    ],
                ];
                $this->messenger()
                    ->addWarning($this->renderer
                    ->renderInIsolation($message));
            }
        }
        // Store the comparer for use in the submit.
        $form_state->set('storage_comparer', $storage_comparer);
        // Add the AJAX library to the form for dialog support.
        $form['#attached']['library'][] = 'core/drupal.dialog.ajax';
        foreach ($storage_comparer->getAllCollectionNames() as $collection) {
            if ($collection != StorageInterface::DEFAULT_COLLECTION) {
                $form[$collection]['collection_heading'] = [
                    '#type' => 'html_tag',
                    '#tag' => 'h2',
                    '#value' => $this->t('@collection configuration collection', [
                        '@collection' => $collection,
                    ]),
                ];
            }
            foreach ($storage_comparer->getChangelist(NULL, $collection) as $config_change_type => $config_names) {
                if (empty($config_names)) {
                    continue;
                }
                // @todo A table caption would be more appropriate, but does not have the
                //   visual importance of a heading.
                $form[$collection][$config_change_type]['heading'] = [
                    '#type' => 'html_tag',
                    '#tag' => 'h3',
                ];
                switch ($config_change_type) {
                    case 'create':
                        $form[$collection][$config_change_type]['heading']['#value'] = $this->formatPlural(count($config_names), '@count new', '@count new');
                        break;
                    case 'update':
                        $form[$collection][$config_change_type]['heading']['#value'] = $this->formatPlural(count($config_names), '@count changed', '@count changed');
                        break;
                    case 'delete':
                        $form[$collection][$config_change_type]['heading']['#value'] = $this->formatPlural(count($config_names), '@count removed', '@count removed');
                        break;
                    case 'rename':
                        $form[$collection][$config_change_type]['heading']['#value'] = $this->formatPlural(count($config_names), '@count renamed', '@count renamed');
                        break;
                }
                $form[$collection][$config_change_type]['list'] = [
                    '#type' => 'table',
                    '#header' => [
                        $this->t('Name'),
                        $this->t('Operations'),
                    ],
                ];
                foreach ($config_names as $config_name) {
                    if ($config_change_type == 'rename') {
                        $names = $storage_comparer->extractRenameNames($config_name);
                        $route_options = [
                            'source_name' => $names['old_name'],
                            'target_name' => $names['new_name'],
                        ];
                        $config_name = $this->t('@source_name to @target_name', [
                            '@source_name' => $names['old_name'],
                            '@target_name' => $names['new_name'],
                        ]);
                    }
                    else {
                        $route_options = [
                            'source_name' => $config_name,
                        ];
                    }
                    if ($collection != StorageInterface::DEFAULT_COLLECTION) {
                        $route_name = 'config.diff_collection';
                        $route_options['collection'] = $collection;
                    }
                    else {
                        $route_name = 'config.diff';
                    }
                    $links['view_diff'] = [
                        'title' => $this->t('View differences'),
                        'url' => Url::fromRoute($route_name, $route_options),
                        'attributes' => [
                            'class' => [
                                'use-ajax',
                            ],
                            'data-dialog-type' => 'modal',
                            'data-dialog-options' => json_encode([
                                'width' => 700,
                            ]),
                        ],
                    ];
                    $form[$collection][$config_change_type]['list']['#rows'][] = [
                        'name' => $config_name,
                        'operations' => [
                            'data' => [
                                '#type' => 'operations',
                                '#links' => $links,
                            ],
                        ],
                    ];
                }
            }
        }
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitForm(array &$form, FormStateInterface $form_state) {
        $config_importer = new ConfigImporter($form_state->get('storage_comparer'), $this->eventDispatcher, $this->configManager, $this->lock, $this->typedConfigManager, $this->moduleHandler, $this->moduleInstaller, $this->themeHandler, $this->getStringTranslation(), $this->moduleExtensionList, $this->themeExtensionList);
        if ($config_importer->alreadyImporting()) {
            $this->messenger()
                ->addStatus($this->t('Another request may be synchronizing configuration already.'));
        }
        else {
            try {
                $sync_steps = $config_importer->initialize();
                $batch_builder = (new BatchBuilder())->setTitle($this->t('Synchronizing configuration'))
                    ->setFinishCallback([
                    ConfigImporterBatch::class,
                    'finish',
                ])
                    ->setInitMessage($this->t('Starting configuration synchronization.'))
                    ->setProgressMessage($this->t('Completed step @current of @total.'))
                    ->setErrorMessage($this->t('Configuration synchronization has encountered an error.'));
                foreach ($sync_steps as $sync_step) {
                    $batch_builder->addOperation([
                        ConfigImporterBatch::class,
                        'process',
                    ], [
                        $config_importer,
                        $sync_step,
                    ]);
                }
                batch_set($batch_builder->toArray());
            } catch (ConfigImporterException) {
                // There are validation errors.
                $this->messenger()
                    ->addError($this->t('The configuration cannot be imported because it failed validation for the following reasons:'));
                foreach ($config_importer->getErrors() as $message) {
                    $this->messenger()
                        ->addError($message);
                }
            }
        }
    }

}