class ImageResize

class ImageResize extends CKEditor5PluginDefault implements CKEditor5PluginConfigurableInterface {
    use CKEditor5PluginConfigurableTrait;
    
    /**
     * {@inheritdoc}
     */
    public function defaultConfiguration() {
        return [
            'allow_resize' => TRUE,
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
        $form['allow_resize'] = [
            '#type' => 'checkbox',
            '#title' => $this->t('Allow the user to resize images'),
            '#default_value' => $this->configuration['allow_resize'],
        ];
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function validateConfigurationForm(array &$form, FormStateInterface $form_state) {
        // Match the config schema structure at ckeditor5.plugin.ckeditor5_imageResize.
        $form_value = $form_state->getValue('allow_resize');
        $form_state->setValue('allow_resize', (bool) $form_value);
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
        $this->configuration['allow_resize'] = $form_state->getValue('allow_resize');
    }

}