class MenuDevelGenerate

class MenuDevelGenerate extends DevelGenerateBase implements ContainerFactoryPluginInterface {
    
    /**
     * The menu tree service.
     *
     * @var \Drupal\Core\Menu\MenuLinkTreeInterface
     */
    protected $menuLinkTree;
    
    /**
     * The menu storage.
     *
     * @var \Drupal\Core\Entity\EntityStorageInterface
     */
    protected $menuStorage;
    
    /**
     * The menu link storage.
     *
     * @var \Drupal\Core\Entity\EntityStorageInterface
     */
    protected $menuLinkContentStorage;
    
    /**
     * The module handler.
     *
     * @var \Drupal\Core\Extension\ModuleHandlerInterface
     */
    protected $moduleHandler;
    
    /**
     * Database connection.
     *
     * @var \Drupal\Core\Database\Connection
     */
    protected $database;
    
    /**
     * Constructs a MenuDevelGenerate object.
     *
     * @param array $configuration
     *   A configuration array containing information about the plugin instance.
     * @param string $plugin_id
     *   The plugin ID for the plugin instance.
     * @param mixed $plugin_definition
     *   The plugin implementation definition.
     * @param \Drupal\Core\Menu\MenuLinkTreeInterface $menu_tree
     *   The menu tree service.
     * @param \Drupal\Core\Entity\EntityStorageInterface $menu_storage
     *   The menu storage.
     * @param \Drupal\Core\Entity\EntityStorageInterface $menu_link_storage
     *   The menu storage.
     * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
     *   The module handler.
     * @param \Drupal\Core\Database\Connection $database
     *   Database connection.
     */
    public function __construct(array $configuration, $plugin_id, $plugin_definition, MenuLinkTreeInterface $menu_tree, EntityStorageInterface $menu_storage, EntityStorageInterface $menu_link_storage, ModuleHandlerInterface $module_handler, Connection $database) {
        parent::__construct($configuration, $plugin_id, $plugin_definition);
        $this->menuLinkTree = $menu_tree;
        $this->menuStorage = $menu_storage;
        $this->menuLinkContentStorage = $menu_link_storage;
        $this->moduleHandler = $module_handler;
        $this->database = $database;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
        $entity_type_manager = $container->get('entity_type.manager');
        return new static($configuration, $plugin_id, $plugin_definition, $container->get('menu.link_tree'), $entity_type_manager->getStorage('menu'), $entity_type_manager->getStorage('menu_link_content'), $container->get('module_handler'), $container->get('database'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function settingsForm(array $form, FormStateInterface $form_state) {
        $menus = array_map(function ($menu) {
            return $menu->label();
        }, Menu::loadMultiple());
        asort($menus);
        $menus = [
            '__new-menu__' => $this->t('Create new menu(s)'),
        ] + $menus;
        $form['existing_menus'] = [
            '#type' => 'checkboxes',
            '#title' => $this->t('Generate links for these menus'),
            '#options' => $menus,
            '#default_value' => [
                '__new-menu__',
            ],
            '#required' => TRUE,
        ];
        $form['num_menus'] = [
            '#type' => 'number',
            '#title' => $this->t('Number of new menus to create'),
            '#default_value' => $this->getSetting('num_menus'),
            '#min' => 0,
            '#states' => [
                'visible' => [
                    ':input[name="existing_menus[__new-menu__]"]' => [
                        'checked' => TRUE,
                    ],
                ],
            ],
        ];
        $form['num_links'] = [
            '#type' => 'number',
            '#title' => $this->t('Number of links to generate'),
            '#default_value' => $this->getSetting('num_links'),
            '#required' => TRUE,
            '#min' => 0,
        ];
        $form['title_length'] = [
            '#type' => 'number',
            '#title' => $this->t('Maximum length for menu titles and menu links'),
            '#description' => $this->t('Text will be generated at random lengths up to this value. Enter a number between 2 and 128.'),
            '#default_value' => $this->getSetting('title_length'),
            '#required' => TRUE,
            '#min' => 2,
            '#max' => 128,
        ];
        $form['link_types'] = [
            '#type' => 'checkboxes',
            '#title' => $this->t('Types of links to generate'),
            '#options' => [
                'node' => $this->t('Nodes'),
                'front' => $this->t('Front page'),
                'external' => $this->t('External'),
            ],
            '#default_value' => [
                'node',
                'front',
                'external',
            ],
            '#required' => TRUE,
        ];
        $form['max_depth'] = [
            '#type' => 'select',
            '#title' => $this->t('Maximum link depth'),
            '#options' => range(0, $this->menuLinkTree
                ->maxDepth()),
            '#default_value' => floor($this->menuLinkTree
                ->maxDepth() / 2),
            '#required' => TRUE,
        ];
        unset($form['max_depth']['#options'][0]);
        $form['max_width'] = [
            '#type' => 'number',
            '#title' => $this->t('Maximum menu width'),
            '#default_value' => $this->getSetting('max_width'),
            '#description' => $this->t("Limit the width of the generated menu's first level of links to a certain number of items."),
            '#required' => TRUE,
            '#min' => 0,
        ];
        $form['kill'] = [
            '#type' => 'checkbox',
            '#title' => $this->t('Delete existing custom generated menus and menu links before generating new ones.'),
            '#default_value' => $this->getSetting('kill'),
        ];
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function generateElements(array $values) {
        // If the create new menus checkbox is off, set the number of menus to 0.
        if (!isset($values['existing_menus']['__new-menu__']) || !$values['existing_menus']['__new-menu__']) {
            $values['num_menus'] = 0;
        }
        else {
            // Unset the aux menu to avoid attach menu new items.
            unset($values['existing_menus']['__new-menu__']);
        }
        // Delete custom menus.
        if ($values['kill']) {
            [
                $menus_deleted,
                $links_deleted,
            ] = $this->deleteMenus();
            $this->setMessage($this->t('Deleted @menus_deleted menu(s) and @links_deleted other link(s).', [
                '@menus_deleted' => $menus_deleted,
                '@links_deleted' => $links_deleted,
            ]));
        }
        // Generate new menus.
        $new_menus = $this->generateMenus($values['num_menus'], $values['title_length']);
        if (!empty($new_menus)) {
            $this->setMessage($this->formatPlural(count($new_menus), 'Created the following 1 new menu: @menus', 'Created the following @count new menus: @menus', [
                '@menus' => implode(', ', $new_menus),
            ]));
        }
        // Generate new menu links.
        $menus = $new_menus;
        if (isset($values['existing_menus'])) {
            $menus = $menus + $values['existing_menus'];
        }
        $new_links = $this->generateLinks($values['num_links'], $menus, $values['title_length'], $values['link_types'], $values['max_depth'], $values['max_width']);
        $this->setMessage($this->formatPlural(count($new_links), 'Created 1 new menu link.', 'Created @count new menu links.'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function validateDrushParams(array $args, array $options = []) {
        $link_types = [
            'node',
            'front',
            'external',
        ];
        $values = [
            'num_menus' => array_shift($args),
            'num_links' => array_shift($args),
            'kill' => $options['kill'],
            'pipe' => $options['pipe'],
            'link_types' => array_combine($link_types, $link_types),
        ];
        $max_depth = array_shift($args);
        $max_width = array_shift($args);
        $values['max_depth'] = $max_depth ? $max_depth : 3;
        $values['max_width'] = $max_width ? $max_width : 8;
        $values['title_length'] = $this->getSetting('title_length');
        $values['existing_menus']['__new-menu__'] = TRUE;
        if ($this->isNumber($values['num_menus']) == FALSE) {
            throw new \Exception(dt('Invalid number of menus'));
        }
        if ($this->isNumber($values['num_links']) == FALSE) {
            throw new \Exception(dt('Invalid number of links'));
        }
        if ($this->isNumber($values['max_depth']) == FALSE || $values['max_depth'] > 9 || $values['max_depth'] < 1) {
            throw new \Exception(dt('Invalid maximum link depth. Use a value between 1 and 9'));
        }
        if ($this->isNumber($values['max_width']) == FALSE || $values['max_width'] < 1) {
            throw new \Exception(dt('Invalid maximum menu width. Use a positive numeric value.'));
        }
        return $values;
    }
    
    /**
     * Deletes custom generated menus.
     */
    protected function deleteMenus() {
        if ($this->moduleHandler
            ->moduleExists('menu_ui')) {
            $menu_ids = [];
            foreach (menu_ui_get_menus(FALSE) as $menu => $menu_title) {
                if (strpos($menu, 'devel-') === 0) {
                    $menu_ids[] = $menu;
                }
            }
            if ($menu_ids) {
                $menus = $this->menuStorage
                    ->loadMultiple($menu_ids);
                $this->menuStorage
                    ->delete($menus);
            }
        }
        // Delete menu links in other menus, but generated by devel.
        $link_ids = $this->menuLinkContentStorage
            ->getQuery()
            ->condition('menu_name', 'devel', '<>')
            ->condition('link__options', '%' . $this->database
            ->escapeLike('s:5:"devel";b:1') . '%', 'LIKE')
            ->execute();
        if ($link_ids) {
            $links = $this->menuLinkContentStorage
                ->loadMultiple($link_ids);
            $this->menuLinkContentStorage
                ->delete($links);
        }
        return [
            count($menu_ids),
            count($link_ids),
        ];
    }
    
    /**
     * Generates new menus.
     *
     * @param int $num_menus
     *   Number of menus to create.
     * @param int $title_length
     *   (optional) Maximum length of menu name.
     *
     * @return array
     *   Array containing the generated menus.
     */
    protected function generateMenus($num_menus, $title_length = 12) {
        $menus = [];
        for ($i = 1; $i <= $num_menus; $i++) {
            $name = $this->randomSentenceOfLength(mt_rand(2, $title_length));
            // Create a random string of random length for the menu id. The maximum
            // machine-name length is 32, so allowing for prefix 'devel-' we can have
            // up to 26 here. For safety avoid accidentally reusing the same id.
            do {
                $id = 'devel-' . $this->getRandom()
                    ->word(mt_rand(2, 26));
            } while (array_key_exists($id, $menus));
            $menu = $this->menuStorage
                ->create([
                'label' => $name,
                'id' => $id,
                'description' => $this->t('Description of @name', [
                    '@name' => $name,
                ]),
            ]);
            $menu->save();
            $menus[$menu->id()] = $menu->label();
        }
        return $menus;
    }
    
    /**
     * Generates menu links in a tree structure.
     */
    protected function generateLinks($num_links, $menus, $title_length, $link_types, $max_depth, $max_width) {
        $links = [];
        $menus = array_keys(array_filter($menus));
        $link_types = array_keys(array_filter($link_types));
        $nids = [];
        for ($i = 1; $i <= $num_links; $i++) {
            // Pick a random menu.
            $menu_name = $menus[array_rand($menus)];
            // Build up our link.
            $link_title = $this->getRandom()
                ->word(mt_rand(2, max(2, $title_length)));
            $link = $this->menuLinkContentStorage
                ->create([
                'menu_name' => $menu_name,
                'weight' => mt_rand(-50, 50),
                'title' => $link_title,
                'bundle' => 'menu_link_content',
                'description' => $this->t('Description of @title.', [
                    '@title' => $link_title,
                ]),
            ]);
            $link->link->options = [
                'devel' => TRUE,
            ];
            // For the first $max_width items, make first level links.
            if ($i <= $max_width) {
                $depth = 0;
            }
            else {
                // Otherwise, get a random parent menu depth.
                $depth = mt_rand(1, max(1, $max_depth - 1));
            }
            // Get a random parent link from the proper depth.
            do {
                $parameters = new MenuTreeParameters();
                $parameters->setMinDepth($depth);
                $parameters->setMaxDepth($depth);
                $tree = $this->menuLinkTree
                    ->load($menu_name, $parameters);
                if ($tree) {
                    $link->parent = array_rand($tree);
                }
                $depth--;
            } while (!$link->parent && $depth > 0);
            $link_type = array_rand($link_types);
            switch ($link_types[$link_type]) {
                case 'node':
                    // Grab a random node ID.
                    $select = $this->database
                        ->select('node_field_data', 'n')
                        ->fields('n', [
                        'nid',
                        'title',
                    ])
                        ->condition('n.status', 1)
                        ->range(0, 1)
                        ->orderRandom();
                    // Don't put a node into the menu twice.
                    if (!empty($nids[$menu_name])) {
                        $select->condition('n.nid', $nids[$menu_name], 'NOT IN');
                    }
                    $node = $select->execute()
                        ->fetchAssoc();
                    if (isset($node['nid'])) {
                        $nids[$menu_name][] = $node['nid'];
                        $link->link->uri = 'entity:node/' . $node['nid'];
                        $link->title = $node['title'];
                        break;
                    }
                case 'external':
                    $link->link->uri = 'http://www.example.com/';
                    break;
                case 'front':
                    $link->link->uri = 'internal:/<front>';
                    break;
                default:
                    $link->devel_link_type = $link_type;
                    break;
            }
            $link->save();
            $links[$link->id()] = $link->link_title;
        }
        return $links;
    }

}