class UserRole

class UserRole extends ConditionPluginBase {
    
    /**
     * {@inheritdoc}
     */
    public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
        $form['roles'] = [
            '#type' => 'checkboxes',
            '#title' => $this->t('When the user has the following roles'),
            '#default_value' => $this->configuration['roles'],
            '#options' => array_map('\\Drupal\\Component\\Utility\\Html::escape', user_role_names()),
            '#description' => $this->t('If you select no roles, the condition will evaluate to TRUE for all users.'),
        ];
        return parent::buildConfigurationForm($form, $form_state);
    }
    
    /**
     * {@inheritdoc}
     */
    public function defaultConfiguration() {
        return [
            'roles' => [],
        ] + parent::defaultConfiguration();
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
        $this->configuration['roles'] = array_filter($form_state->getValue('roles'));
        parent::submitConfigurationForm($form, $form_state);
    }
    
    /**
     * {@inheritdoc}
     */
    public function summary() {
        // Use the role labels. They will be sanitized below.
        $roles = array_intersect_key(user_role_names(), $this->configuration['roles']);
        if (count($roles) > 1) {
            $roles = implode(', ', $roles);
        }
        else {
            $roles = reset($roles);
        }
        if (!empty($this->configuration['negate'])) {
            return $this->t('The user is not a member of @roles', [
                '@roles' => $roles,
            ]);
        }
        else {
            return $this->t('The user is a member of @roles', [
                '@roles' => $roles,
            ]);
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function evaluate() {
        if (empty($this->configuration['roles']) && !$this->isNegated()) {
            return TRUE;
        }
        $user = $this->getContextValue('user');
        return (bool) array_intersect($this->configuration['roles'], $user->getRoles());
    }
    
    /**
     * {@inheritdoc}
     */
    public function getCacheContexts() {
        // Optimize cache context, if a user cache context is provided, only use
        // user.roles, since that's the only part this condition cares about.
        $contexts = [];
        foreach (parent::getCacheContexts() as $context) {
            $contexts[] = $context == 'user' ? 'user.roles' : $context;
        }
        return $contexts;
    }

}