class VocabularyDevelGenerate

class VocabularyDevelGenerate extends DevelGenerateBase implements ContainerFactoryPluginInterface {
    
    /**
     * The vocabulary storage.
     *
     * @var \Drupal\Core\Entity\EntityStorageInterface
     */
    protected $vocabularyStorage;
    
    /**
     * Constructs a new VocabularyDevelGenerate 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\Entity\EntityStorageInterface $entity_storage
     *   The vocabulary storage.
     */
    public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityStorageInterface $entity_storage) {
        parent::__construct($configuration, $plugin_id, $plugin_definition);
        $this->vocabularyStorage = $entity_storage;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
        return new static($configuration, $plugin_id, $plugin_definition, $container->get('entity_type.manager')
            ->getStorage('taxonomy_vocabulary'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function settingsForm(array $form, FormStateInterface $form_state) {
        $form['num'] = [
            '#type' => 'number',
            '#title' => $this->t('Number of vocabularies?'),
            '#default_value' => $this->getSetting('num'),
            '#required' => TRUE,
            '#min' => 0,
        ];
        $form['title_length'] = [
            '#type' => 'number',
            '#title' => $this->t('Maximum number of characters in vocabulary names'),
            '#default_value' => $this->getSetting('title_length'),
            '#required' => TRUE,
            '#min' => 2,
            '#max' => 255,
        ];
        $form['kill'] = [
            '#type' => 'checkbox',
            '#title' => $this->t('Delete existing vocabularies before generating new ones.'),
            '#default_value' => $this->getSetting('kill'),
        ];
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function generateElements(array $values) {
        if ($values['kill']) {
            $this->deleteVocabularies();
            $this->setMessage($this->t('Deleted existing vocabularies.'));
        }
        $new_vocs = $this->generateVocabularies($values['num'], $values['title_length']);
        if (!empty($new_vocs)) {
            $this->setMessage($this->t('Created the following new vocabularies: @vocs', [
                '@vocs' => implode(', ', $new_vocs),
            ]));
        }
    }
    
    /**
     * Deletes all vocabularies.
     */
    protected function deleteVocabularies() {
        $vocabularies = $this->vocabularyStorage
            ->loadMultiple();
        $this->vocabularyStorage
            ->delete($vocabularies);
    }
    
    /**
     * Generates vocabularies.
     *
     * @param int $records
     *   Number of vocabularies to create.
     * @param int $maxlength
     *   (optional) Maximum length for vocabulary name.
     *
     * @return array
     *   Array containing the generated vocabularies id.
     */
    protected function generateVocabularies($records, $maxlength = 12) {
        $vocabularies = [];
        // Insert new data:
        for ($i = 1; $i <= $records; $i++) {
            $name = $this->getRandom()
                ->word(mt_rand(2, $maxlength));
            $vocabulary = $this->vocabularyStorage
                ->create([
                'name' => $name,
                'vid' => mb_strtolower($name),
                'langcode' => Language::LANGCODE_NOT_SPECIFIED,
                'description' => "Description of {$name}",
                'hierarchy' => 1,
                'weight' => mt_rand(0, 10),
                'multiple' => 1,
                'required' => 0,
                'relations' => 1,
            ]);
            // Populate all fields with sample values.
            $this->populateFields($vocabulary);
            $vocabulary->save();
            $vocabularies[] = $vocabulary->id();
            unset($vocabulary);
        }
        return $vocabularies;
    }
    
    /**
     * {@inheritdoc}
     */
    public function validateDrushParams(array $args, array $options = []) {
        $values = [
            'num' => array_shift($args),
            'kill' => $options['kill'],
            'title_length' => 12,
        ];
        if ($this->isNumber($values['num']) == FALSE) {
            throw new \Exception(dt('Invalid number of vocabularies: @num.', [
                '@num' => $values['num'],
            ]));
        }
        return $values;
    }

}