class DbUpdateController

class DbUpdateController extends ControllerBase {
    
    /**
     * The keyvalue expirable factory.
     *
     * @var \Drupal\Core\KeyValueStore\KeyValueExpirableFactoryInterface
     */
    protected $keyValueExpirableFactory;
    
    /**
     * A cache backend interface.
     *
     * @var \Drupal\Core\Cache\CacheBackendInterface
     */
    protected $cache;
    
    /**
     * The state service.
     *
     * @var \Drupal\Core\State\StateInterface
     */
    protected $state;
    
    /**
     * The module handler.
     *
     * @var \Drupal\Core\Extension\ModuleHandlerInterface
     */
    protected $moduleHandler;
    
    /**
     * The current user.
     *
     * @var \Drupal\Core\Session\AccountInterface
     */
    protected $account;
    
    /**
     * The bare HTML page renderer.
     *
     * @var \Drupal\Core\Render\BareHtmlPageRendererInterface
     */
    protected $bareHtmlPageRenderer;
    
    /**
     * The app root.
     *
     * @var string
     */
    protected $root;
    
    /**
     * The post update registry.
     *
     * @var \Drupal\Core\Update\UpdateRegistry
     */
    protected $postUpdateRegistry;
    
    /**
     * Constructs a new UpdateController.
     *
     * @param string $root
     *   The app root.
     * @param \Drupal\Core\KeyValueStore\KeyValueExpirableFactoryInterface $key_value_expirable_factory
     *   The keyvalue expirable factory.
     * @param \Drupal\Core\Cache\CacheBackendInterface $cache
     *   A cache backend interface.
     * @param \Drupal\Core\State\StateInterface $state
     *   The state service.
     * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
     *   The module handler.
     * @param \Drupal\Core\Session\AccountInterface $account
     *   The current user.
     * @param \Drupal\Core\Render\BareHtmlPageRendererInterface $bare_html_page_renderer
     *   The bare HTML page renderer.
     * @param \Drupal\Core\Update\UpdateRegistry $post_update_registry
     *   The post update registry.
     */
    public function __construct($root, KeyValueExpirableFactoryInterface $key_value_expirable_factory, CacheBackendInterface $cache, StateInterface $state, ModuleHandlerInterface $module_handler, AccountInterface $account, BareHtmlPageRendererInterface $bare_html_page_renderer, UpdateRegistry $post_update_registry) {
        $this->root = $root;
        $this->keyValueExpirableFactory = $key_value_expirable_factory;
        $this->cache = $cache;
        $this->state = $state;
        $this->moduleHandler = $module_handler;
        $this->account = $account;
        $this->bareHtmlPageRenderer = $bare_html_page_renderer;
        $this->postUpdateRegistry = $post_update_registry;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container) {
        return new static($container->getParameter('app.root'), $container->get('keyvalue.expirable'), $container->get('cache.default'), $container->get('state'), $container->get('module_handler'), $container->get('current_user'), $container->get('bare_html_page_renderer'), $container->get('update.post_update_registry'));
    }
    
    /**
     * Returns a database update page.
     *
     * @param string $op
     *   The update operation to perform. Can be any of the below:
     *    - info
     *    - selection
     *    - run
     *    - results
     * @param \Symfony\Component\HttpFoundation\Request $request
     *   The current request object.
     *
     * @return \Symfony\Component\HttpFoundation\Response
     *   A response object.
     */
    public function handle($op, Request $request) {
        require_once $this->root . '/core/includes/install.inc';
        require_once $this->root . '/core/includes/update.inc';
        drupal_load_updates();
        if ($request->query
            ->get('continue')) {
            $request->getSession()
                ->set('update_ignore_warnings', TRUE);
        }
        $regions = [];
        $requirements = update_check_requirements();
        $severity = drupal_requirements_severity($requirements);
        if ($severity == REQUIREMENT_ERROR || $severity == REQUIREMENT_WARNING && !$request->getSession()
            ->has('update_ignore_warnings')) {
            $regions['sidebar_first'] = $this->updateTasksList('requirements');
            $output = $this->requirements($severity, $requirements, $request);
        }
        else {
            switch ($op) {
                case 'selection':
                    $regions['sidebar_first'] = $this->updateTasksList('selection');
                    $output = $this->selection($request);
                    break;
                case 'run':
                    $regions['sidebar_first'] = $this->updateTasksList('run');
                    $output = $this->triggerBatch($request);
                    break;
                case 'info':
                    $regions['sidebar_first'] = $this->updateTasksList('info');
                    $output = $this->info($request);
                    break;
                case 'results':
                    $regions['sidebar_first'] = $this->updateTasksList('results');
                    $output = $this->results($request);
                    break;
                // Regular batch ops : defer to batch processing API.
                default:
                    require_once $this->root . '/core/includes/batch.inc';
                    $regions['sidebar_first'] = $this->updateTasksList('run');
                    $output = _batch_page($request);
                    break;
            }
        }
        if ($output instanceof Response) {
            return $output;
        }
        $title = $output['#title'] ?? $this->t('Drupal database update');
        return $this->bareHtmlPageRenderer
            ->renderBarePage($output, $title, 'maintenance_page', $regions);
    }
    
    /**
     * Returns the info database update page.
     *
     * @param \Symfony\Component\HttpFoundation\Request $request
     *   The current request.
     *
     * @return array
     *   A render array.
     */
    protected function info(Request $request) {
        // Change query-strings on css/js files to enforce reload for all users.
        _drupal_flush_css_js();
        // Flush the cache of all data for the update status module.
        $this->keyValueExpirableFactory
            ->get('update')
            ->deleteAll();
        $this->keyValueExpirableFactory
            ->get('update_available_release')
            ->deleteAll();
        $build['info_header'] = [
            '#markup' => '<p>' . $this->t('Use this utility to update your database whenever a new release of Drupal or a module is installed.') . '</p><p>' . $this->t('For more detailed information, see the <a href="https://www.drupal.org/docs/updating-drupal">Updating Drupal guide</a>. If you are unsure what these terms mean you should probably contact your hosting provider.') . '</p>',
        ];
        $info[] = $this->t("<strong>Back up your code</strong>. Hint: when backing up module code, do not leave that backup in the 'modules' or 'sites/*/modules' directories as this may confuse Drupal's auto-discovery mechanism.");
        // @todo Simplify with https://www.drupal.org/node/2548095
        $base_url = str_replace('/update.php', '', $request->getBaseUrl());
        $info[] = $this->t('Put your site into <a href=":url">maintenance mode</a>.', [
            ':url' => Url::fromRoute('system.site_maintenance_mode')->setOption('base_url', $base_url)
                ->toString(TRUE)
                ->getGeneratedUrl(),
        ]);
        $info[] = $this->t('<strong>Back up your database</strong>. This process will change your database values and in case of emergency you may need to revert to a backup.');
        $info[] = $this->t('Install your new files in the appropriate location, as described in the handbook.');
        $build['info'] = [
            '#theme' => 'item_list',
            '#list_type' => 'ol',
            '#items' => $info,
        ];
        $build['info_footer'] = [
            '#markup' => '<p>' . $this->t('When you have performed the steps above, you may proceed.') . '</p>',
        ];
        $build['link'] = [
            '#type' => 'link',
            '#title' => $this->t('Continue'),
            '#attributes' => [
                'class' => [
                    'button',
                    'button--primary',
                ],
            ],
            // @todo Revisit once https://www.drupal.org/node/2548095 is in.
'#url' => Url::fromUri('base://selection'),
        ];
        return $build;
    }
    
    /**
     * Renders a list of available database updates.
     *
     * @param \Symfony\Component\HttpFoundation\Request $request
     *   The current request.
     *
     * @return array
     *   A render array.
     */
    protected function selection(Request $request) {
        // Make sure there is no stale theme registry.
        $this->cache
            ->deleteAll();
        $count = 0;
        $incompatible_count = 0;
        $build['start'] = [
            '#tree' => TRUE,
            '#type' => 'details',
        ];
        // Ensure system.module's updates appear first.
        $build['start']['system'] = [];
        $starting_updates = [];
        $incompatible_updates_exist = FALSE;
        $updates_per_extension = [];
        foreach ([
            'update',
            'post_update',
        ] as $update_type) {
            switch ($update_type) {
                case 'update':
                    $updates = update_get_update_list();
                    break;
                case 'post_update':
                    $updates = $this->postUpdateRegistry
                        ->getPendingUpdateInformation();
                    break;
            }
            foreach ($updates as $extension => $update) {
                if (!isset($update['start'])) {
                    $build['start'][$extension] = [
                        '#type' => 'item',
                        '#title' => $extension . ($this->moduleHandler
                            ->moduleExists($extension) ? ' module' : ' theme'),
                        '#markup' => $update['warning'],
                        '#prefix' => '<div class="messages messages--warning">',
                        '#suffix' => '</div>',
                    ];
                    $incompatible_updates_exist = TRUE;
                    continue;
                }
                if (!empty($update['pending'])) {
                    $updates_per_extension += [
                        $extension => [],
                    ];
                    $updates_per_extension[$extension] = array_merge($updates_per_extension[$extension], $update['pending']);
                    $build['start'][$extension] = [
                        '#type' => 'hidden',
                        '#value' => $update['start'],
                    ];
                    // Store the previous items in order to merge normal updates and
                    // post_update functions together.
                    $build['start'][$extension] = [
                        '#theme' => 'item_list',
                        '#items' => $updates_per_extension[$extension],
                        '#title' => $extension . ($this->moduleHandler
                            ->moduleExists($extension) ? ' module' : ' theme'),
                    ];
                    if ($update_type === 'update') {
                        $starting_updates[$extension] = $update['start'];
                    }
                }
                if (isset($update['pending'])) {
                    $count = $count + count($update['pending']);
                }
            }
        }
        // Find and label any incompatible updates.
        foreach (update_resolve_dependencies($starting_updates) as $data) {
            if (!$data['allowed']) {
                $incompatible_updates_exist = TRUE;
                $incompatible_count++;
                $module_update_key = $data['module'] . '_updates';
                if (isset($build['start'][$module_update_key]['#items'][$data['number']])) {
                    if ($data['missing_dependencies']) {
                        $text = $this->t('This update will been skipped due to the following missing dependencies:') . '<em>' . implode(', ', $data['missing_dependencies']) . '</em>';
                    }
                    else {
                        $text = $this->t("This update will be skipped due to an error in the module's code.");
                    }
                    $build['start'][$module_update_key]['#items'][$data['number']] .= '<div class="warning">' . $text . '</div>';
                }
                // Move the module containing this update to the top of the list.
                $build['start'] = [
                    $module_update_key => $build['start'][$module_update_key],
                ] + $build['start'];
            }
        }
        // Warn the user if any updates were incompatible.
        if ($incompatible_updates_exist) {
            $this->messenger()
                ->addWarning($this->t('Some of the pending updates cannot be applied because their dependencies were not met.'));
        }
        if (empty($count)) {
            $this->messenger()
                ->addStatus($this->t('No pending updates.'));
            unset($build);
            $build['links'] = [
                '#theme' => 'links',
                '#links' => $this->helpfulLinks($request),
            ];
            // No updates to run, so caches won't get flushed later.  Clear them now.
            drupal_flush_all_caches();
        }
        else {
            $build['help'] = [
                '#markup' => '<p>' . $this->t('The version of Drupal you are updating from has been automatically detected.') . '</p>',
                '#weight' => -5,
            ];
            if ($incompatible_count) {
                $build['start']['#title'] = $this->formatPlural($count, '1 pending update (@number_applied to be applied, @number_incompatible skipped)', '@count pending updates (@number_applied to be applied, @number_incompatible skipped)', [
                    '@number_applied' => $count - $incompatible_count,
                    '@number_incompatible' => $incompatible_count,
                ]);
            }
            else {
                $build['start']['#title'] = $this->formatPlural($count, '1 pending update', '@count pending updates');
            }
            // @todo Simplify with https://www.drupal.org/node/2548095
            $base_url = str_replace('/update.php', '', $request->getBaseUrl());
            $url = (new Url('system.db_update', [
                'op' => 'run',
            ]))->setOption('base_url', $base_url);
            $build['link'] = [
                '#type' => 'link',
                '#title' => $this->t('Apply pending updates'),
                '#attributes' => [
                    'class' => [
                        'button',
                        'button--primary',
                    ],
                ],
                '#weight' => 5,
                '#url' => $url,
                '#access' => $url->access($this->currentUser()),
            ];
        }
        return $build;
    }
    
    /**
     * Displays results of the update script with any accompanying errors.
     *
     * @param \Symfony\Component\HttpFoundation\Request $request
     *   The current request.
     *
     * @return array
     *   A render array.
     */
    protected function results(Request $request) {
        // @todo Simplify with https://www.drupal.org/node/2548095
        $base_url = str_replace('/update.php', '', $request->getBaseUrl());
        // Retrieve and remove session information.
        $session = $request->getSession();
        $update_results = $session->remove('update_results');
        $update_success = $session->remove('update_success');
        $session->remove('update_ignore_warnings');
        // Report end result.
        $dblog_exists = $this->moduleHandler
            ->moduleExists('dblog');
        if ($dblog_exists && $this->account
            ->hasPermission('access site reports')) {
            $log_message = $this->t('All errors have been <a href=":url">logged</a>.', [
                ':url' => Url::fromRoute('dblog.overview')->setOption('base_url', $base_url)
                    ->toString(TRUE)
                    ->getGeneratedUrl(),
            ]);
        }
        else {
            $log_message = $this->t('All errors have been logged.');
        }
        if ($update_success) {
            $message = '<p>' . $this->t('Updates were attempted. If you see no failures below, you may proceed happily back to your <a href=":url">site</a>. Otherwise, you may need to update your database manually.', [
                ':url' => Url::fromRoute('<front>')->setOption('base_url', $base_url)
                    ->toString(TRUE)
                    ->getGeneratedUrl(),
            ]) . ' ' . $log_message . '</p>';
        }
        else {
            $last = $session->get('updates_remaining');
            $last = reset($last);
            [
                $module,
                $version,
            ] = array_pop($last);
            $message = '<p class="error">' . $this->t('The update process was aborted prematurely while running <strong>update #@version in @module.module</strong>.', [
                '@version' => $version,
                '@module' => $module,
            ]) . ' ' . $log_message;
            if ($dblog_exists) {
                $message .= ' ' . $this->t('You may need to check the <code>watchdog</code> database table manually.');
            }
            $message .= '</p>';
        }
        if (Settings::get('update_free_access')) {
            $message .= '<p>' . $this->t("<strong>Reminder: don't forget to set the <code>\$settings['update_free_access']</code> value in your <code>settings.php</code> file back to <code>FALSE</code>.</strong>") . '</p>';
        }
        $build['message'] = [
            '#markup' => $message,
        ];
        $build['links'] = [
            '#theme' => 'links',
            '#links' => $this->helpfulLinks($request),
        ];
        // Output a list of info messages.
        if (!empty($update_results)) {
            $all_messages = [];
            foreach ($update_results as $extension => $updates) {
                if ($extension != '#abort') {
                    $extension_has_message = FALSE;
                    $info_messages = [];
                    foreach ($updates as $name => $queries) {
                        $messages = [];
                        foreach ($queries as $query) {
                            // If there is no message for this update, don't show anything.
                            if (empty($query['query'])) {
                                continue;
                            }
                            if ($query['success']) {
                                $messages[] = [
                                    '#wrapper_attributes' => [
                                        'class' => [
                                            'success',
                                        ],
                                    ],
                                    '#markup' => $query['query'],
                                ];
                            }
                            else {
                                $messages[] = [
                                    '#wrapper_attributes' => [
                                        'class' => [
                                            'failure',
                                        ],
                                    ],
                                    '#markup' => '<strong>' . $this->t('Failed:') . '</strong> ' . $query['query'],
                                ];
                            }
                        }
                        if ($messages) {
                            $extension_has_message = TRUE;
                            if (is_numeric($name)) {
                                $title = $this->t('Update #@count', [
                                    '@count' => $name,
                                ]);
                            }
                            else {
                                $title = $this->t('Update @name', [
                                    '@name' => trim($name, '_'),
                                ]);
                            }
                            $info_messages[] = [
                                '#theme' => 'item_list',
                                '#items' => $messages,
                                '#title' => $title,
                            ];
                        }
                    }
                    // If there were any messages then prefix them with the extension name
                    // and add it to the global message list.
                    if ($extension_has_message) {
                        $header = $this->moduleHandler
                            ->moduleExists($extension) ? $this->t('@module module', [
                            '@module' => $extension,
                        ]) : $this->t('@theme theme', [
                            '@theme' => $extension,
                        ]);
                        $all_messages[] = [
                            '#type' => 'container',
                            '#prefix' => '<h3>' . $header . '</h3>',
                            '#children' => $info_messages,
                        ];
                    }
                }
            }
            if ($all_messages) {
                $build['query_messages'] = [
                    '#type' => 'container',
                    '#children' => $all_messages,
                    '#attributes' => [
                        'class' => [
                            'update-results',
                        ],
                    ],
                    '#prefix' => '<h2>' . $this->t('The following updates returned messages:') . '</h2>',
                ];
            }
        }
        return $build;
    }
    
    /**
     * Renders a list of requirement errors or warnings.
     *
     * @param $severity
     *   The severity of the message, as per RFC 3164.
     * @param array $requirements
     *   The array of requirement values.
     * @param \Symfony\Component\HttpFoundation\Request $request
     *   The current request.
     *
     * @return array
     *   A render array.
     */
    public function requirements($severity, array $requirements, Request $request) {
        $options = $severity == REQUIREMENT_WARNING ? [
            'continue' => 1,
        ] : [];
        // @todo Revisit once https://www.drupal.org/node/2548095 is in. Something
        // like Url::fromRoute('system.db_update')->setOptions() should then be
        // possible.
        $try_again_url = Url::fromUri($request->getUriForPath(''))
            ->setOptions([
            'query' => $options,
        ])
            ->toString(TRUE)
            ->getGeneratedUrl();
        $build['status_report'] = [
            '#type' => 'status_report',
            '#requirements' => $requirements,
            '#suffix' => $this->t('Check the messages and <a href=":url">try again</a>.', [
                ':url' => $try_again_url,
            ]),
        ];
        $build['#title'] = $this->t('Requirements problem');
        return $build;
    }
    
    /**
     * Provides the update task list render array.
     *
     * @param string $active
     *   The active task.
     *   Can be one of 'requirements', 'info', 'selection', 'run', 'results'.
     *
     * @return array
     *   A render array.
     */
    protected function updateTasksList($active = NULL) {
        // Default list of tasks.
        $tasks = [
            'requirements' => $this->t('Verify requirements'),
            'info' => $this->t('Overview'),
            'selection' => $this->t('Review updates'),
            'run' => $this->t('Run updates'),
            'results' => $this->t('Review log'),
        ];
        $task_list = [
            '#theme' => 'maintenance_task_list',
            '#items' => $tasks,
            '#active' => $active,
        ];
        return $task_list;
    }
    
    /**
     * Starts the database update batch process.
     *
     * @param \Symfony\Component\HttpFoundation\Request $request
     *   The current request object.
     */
    protected function triggerBatch(Request $request) {
        $maintenance_mode = $this->state
            ->get('system.maintenance_mode', FALSE);
        // Store the current maintenance mode status in the session so that it can
        // be restored at the end of the batch.
        $request->getSession()
            ->set('maintenance_mode', $maintenance_mode);
        // During the update, always put the site into maintenance mode so that
        // in-progress schema changes do not affect visiting users.
        if (empty($maintenance_mode)) {
            $this->state
                ->set('system.maintenance_mode', TRUE);
        }
        
        /** @var \Drupal\Core\Batch\BatchBuilder $batch_builder */
        $batch_builder = (new BatchBuilder())->setTitle($this->t('Updating'))
            ->setInitMessage($this->t('Starting updates'))
            ->setErrorMessage($this->t('An unrecoverable error has occurred. You can find the error message below. It is advised to copy it to the clipboard for reference.'))
            ->setFinishCallback([
            DbUpdateController::class,
            'batchFinished',
        ]);
        // Resolve any update dependencies to determine the actual updates that will
        // be run and the order they will be run in.
        $start = $this->getModuleUpdates();
        $updates = update_resolve_dependencies($start);
        // Store the dependencies for each update function in an array which the
        // batch API can pass in to the batch operation each time it is called. (We
        // do not store the entire update dependency array here because it is
        // potentially very large.)
        $dependency_map = [];
        foreach ($updates as $function => $update) {
            $dependency_map[$function] = !empty($update['reverse_paths']) ? array_keys($update['reverse_paths']) : [];
        }
        // Determine updates to be performed.
        foreach ($updates as $function => $update) {
            if ($update['allowed']) {
                // Set the installed version of each module so updates will start at the
                // correct place. (The updates are already sorted, so we can simply base
                // this on the first one we come across in the above foreach loop.)
                if (isset($start[$update['module']])) {
                    \Drupal::service('update.update_hook_registry')->setInstalledVersion($update['module'], $update['number'] - 1);
                    unset($start[$update['module']]);
                }
                $batch_builder->addOperation('update_do_one', [
                    $update['module'],
                    $update['number'],
                    $dependency_map[$function],
                ]);
            }
        }
        $post_updates = $this->postUpdateRegistry
            ->getPendingUpdateFunctions();
        if ($post_updates) {
            // Now we rebuild all caches and after that execute the hook_post_update()
            // functions.
            $batch_builder->addOperation('drupal_flush_all_caches', []);
            foreach ($post_updates as $function) {
                $batch_builder->addOperation('update_invoke_post_update', [
                    $function,
                ]);
            }
        }
        batch_set($batch_builder->toArray());
        // @todo Revisit once https://www.drupal.org/node/2548095 is in.
        return batch_process(Url::fromUri('base://results'), Url::fromUri('base://start'));
    }
    
    /**
     * Finishes the update process and stores the results for eventual display.
     *
     * After the updates run, all caches are flushed. The update results are
     * stored into the session (for example, to be displayed on the update results
     * page in update.php). Additionally, if the site was off-line, now that the
     * update process is completed, the site is set back online.
     *
     * @param $success
     *   Indicate that the batch API tasks were all completed successfully.
     * @param array $results
     *   An array of all the results that were updated in update_do_one().
     * @param array $operations
     *   A list of all the operations that had not been completed by the batch API.
     */
    public static function batchFinished($success, $results, $operations) {
        // No updates to run, so caches won't get flushed later.  Clear them now.
        drupal_flush_all_caches();
        $session = \Drupal::request()->getSession();
        $session->set('update_results', $results);
        $session->set('update_success', $success);
        $session->set('updates_remaining', $operations);
        // Now that the update is done, we can put the site back online if it was
        // previously not in maintenance mode.
        if (!$session->remove('maintenance_mode')) {
            \Drupal::state()->set('system.maintenance_mode', FALSE);
        }
    }
    
    /**
     * Provides links to the homepage and administration pages.
     *
     * @param \Symfony\Component\HttpFoundation\Request $request
     *   The current request.
     *
     * @return array
     *   An array of links.
     */
    protected function helpfulLinks(Request $request) {
        // @todo Simplify with https://www.drupal.org/node/2548095
        $base_url = str_replace('/update.php', '', $request->getBaseUrl());
        $links['front'] = [
            'title' => $this->t('Front page'),
            'url' => Url::fromRoute('<front>')->setOption('base_url', $base_url),
        ];
        if ($this->account
            ->hasPermission('access administration pages')) {
            $links['admin-pages'] = [
                'title' => $this->t('Administration pages'),
                'url' => Url::fromRoute('system.admin')->setOption('base_url', $base_url),
            ];
        }
        return $links;
    }
    
    /**
     * Retrieves module updates.
     *
     * @return array
     *   The module updates that can be performed.
     */
    protected function getModuleUpdates() {
        $return = [];
        $updates = update_get_update_list();
        foreach ($updates as $module => $update) {
            $return[$module] = $update['start'];
        }
        return $return;
    }

}