class TermDevelGenerate

class TermDevelGenerate extends DevelGenerateBase implements ContainerFactoryPluginInterface {
    
    /**
     * The vocabulary storage.
     *
     * @var \Drupal\Core\Entity\EntityStorageInterface
     */
    protected $vocabularyStorage;
    
    /**
     * The term storage.
     *
     * @var \Drupal\Core\Entity\EntityStorageInterface
     */
    protected $termStorage;
    
    /**
     * Constructs a new TermDevelGenerate 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 $vocabulary_storage
     *   The vocabulary storage.
     * @param \Drupal\Core\Entity\EntityStorageInterface $term_storage
     *   The term storage.
     */
    public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityStorageInterface $vocabulary_storage, EntityStorageInterface $term_storage) {
        parent::__construct($configuration, $plugin_id, $plugin_definition);
        $this->vocabularyStorage = $vocabulary_storage;
        $this->termStorage = $term_storage;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
        $entity_manager = $container->get('entity.manager');
        return new static($configuration, $plugin_id, $plugin_definition, $entity_manager->getStorage('taxonomy_vocabulary'), $entity_manager->getStorage('taxonomy_term'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function settingsForm(array $form, FormStateInterface $form_state) {
        $options = array();
        foreach ($this->vocabularyStorage
            ->loadMultiple() as $vocabulary) {
            $options[$vocabulary->id()] = $vocabulary->label();
        }
        $form['vids'] = array(
            '#type' => 'select',
            '#multiple' => TRUE,
            '#title' => $this->t('Vocabularies'),
            '#required' => TRUE,
            '#default_value' => 'tags',
            '#options' => $options,
            '#description' => $this->t('Restrict terms to these vocabularies.'),
        );
        $form['num'] = array(
            '#type' => 'number',
            '#title' => $this->t('Number of terms?'),
            '#default_value' => $this->getSetting('num'),
            '#required' => TRUE,
            '#min' => 0,
        );
        $form['title_length'] = array(
            '#type' => 'number',
            '#title' => $this->t('Maximum number of characters in term names'),
            '#default_value' => $this->getSetting('title_length'),
            '#required' => TRUE,
            '#min' => 2,
            '#max' => 255,
        );
        $form['kill'] = array(
            '#type' => 'checkbox',
            '#title' => $this->t('Delete existing terms in specified vocabularies before generating new terms.'),
            '#default_value' => $this->getSetting('kill'),
        );
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function generateElements(array $values) {
        if ($values['kill']) {
            $this->deleteVocabularyTerms($values['vids']);
            $this->setMessage($this->t('Deleted existing terms.'));
        }
        $vocabs = $this->vocabularyStorage
            ->loadMultiple($values['vids']);
        $new_terms = $this->generateTerms($values['num'], $vocabs, $values['title_length']);
        if (!empty($new_terms)) {
            $this->setMessage($this->t('Created the following new terms: @terms', array(
                '@terms' => implode(', ', $new_terms),
            )));
        }
    }
    
    /**
     * Deletes all terms of given vocabularies.
     *
     * @param array $vids
     *   Array of vocabulary vid.
     */
    protected function deleteVocabularyTerms($vids) {
        $tids = $this->vocabularyStorage
            ->getToplevelTids($vids);
        $terms = $this->termStorage
            ->loadMultiple($tids);
        $this->termStorage
            ->delete($terms);
    }
    
    /**
     * Generates taxonomy terms for a list of given vocabularies.
     *
     * @param int $records
     *   Number of terms to create in total.
     * @param \Drupal\taxonomy\TermInterface[] $vocabs
     *   List of vocabularies to populate.
     * @param int $maxlength
     *   (optional) Maximum length per term.
     *
     * @return array
     *   The list of names of the created terms.
     */
    protected function generateTerms($records, $vocabs, $maxlength = 12) {
        $terms = array();
        // Insert new data:
        $max = db_query('SELECT MAX(tid) FROM {taxonomy_term_data}')->fetchField();
        $start = time();
        for ($i = 1; $i <= $records; $i++) {
            $name = $this->getRandom()
                ->word(mt_rand(2, $maxlength));
            $values = array(
                'name' => $name,
                'description' => 'description of ' . $name,
                'format' => filter_fallback_format(),
                'weight' => mt_rand(0, 10),
                'langcode' => Language::LANGCODE_NOT_SPECIFIED,
            );
            switch ($i % 2) {
                case 1:
                    $vocab = $vocabs[array_rand($vocabs)];
                    $values['vid'] = $vocab->id();
                    $values['parent'] = array(
                        0,
                    );
                    break;
                default:
                    while (TRUE) {
                        // Keep trying to find a random parent.
                        $candidate = mt_rand(1, $max);
                        $query = db_select('taxonomy_term_data', 't');
                        $parent = $query->fields('t', array(
                            'tid',
                            'vid',
                        ))
                            ->condition('t.vid', array_keys($vocabs), 'IN')
                            ->condition('t.tid', $candidate, '>=')
                            ->range(0, 1)
                            ->execute()
                            ->fetchAssoc();
                        if ($parent['tid']) {
                            break;
                        }
                    }
                    $values['parent'] = array(
                        $parent['tid'],
                    );
                    // Slight speedup due to this property being set.
                    $values['vid'] = $parent['vid'];
                    break;
            }
            $term = $this->termStorage
                ->create($values);
            // Populate all fields with sample values.
            $this->populateFields($term);
            $term->save();
            $max++;
            // Limit memory usage. Only report first 20 created terms.
            if ($i < 20) {
                $terms[] = $term->label();
            }
            unset($term);
        }
        return $terms;
    }
    
    /**
     * {@inheritdoc}
     */
    public function validateDrushParams($args, $options = []) {
        $vocabulary_name = array_shift($args);
        $number = array_shift($args);
        if ($number === NULL) {
            $number = 10;
        }
        if (!$vocabulary_name) {
            throw new \Exception(dt('Please provide a vocabulary machine name.'));
        }
        if (!$this->isNumber($number)) {
            throw new \Exception(dt('Invalid number of terms: @num', array(
                '@num' => $number,
            )));
        }
        // Try to convert machine name to a vocabulary id.
        if (!($vocabulary = $this->vocabularyStorage
            ->load($vocabulary_name))) {
            throw new \Exception(dt('Invalid vocabulary name: @name', array(
                '@name' => $vocabulary_name,
            )));
        }
        $values = [
            'num' => $number,
            'kill' => $this->isDrush8() ? drush_get_option('kill') : $options['kill'],
            'title_length' => 12,
            'vids' => [
                $vocabulary->id(),
            ],
        ];
        return $values;
    }

}