mailjet-8.x-2.7/src/Form/DomainSaveForm.php

<?php

namespace Drupal\mailjet\Form;

use Drupal\Core\Form\ConfigFormBase;
use Drupal\Core\Form\FormStateInterface;
use Symfony\Component\HttpFoundation\RedirectResponse;

/**
 * Class for DomainSaveForm.
 */
class DomainSaveForm extends ConfigFormBase
{

  /**
   * {@inheritdoc}
   */
  public function getFormId()
  {
    return 'domain_save_custom_admin_form';
  }//end getFormId()

  /**
   * {@inheritdoc}
   */
  protected function getEditableConfigNames()
  {
    return ['config.save_domain'];
  }//end getEditableConfigNames()

  /**
   * {@inheritdoc}
   */
  public function buildForm(array $form, FormStateInterface $form_state)
  {
    $form = [];

    $form['domain'] = [
      '#type' => 'textfield',
      '#title' => t('Domain'),
      '#description' => t('Please enter the domain name that you will be adding to your Mailjet account.'),
      '#required' => FALSE,
    ];

    $form['submit'] = [
      '#type' => 'submit',
      '#value' => t('Add'),
    ];

    return $form;
  }//end buildForm()

  /**
   * {@inheritdoc}
   */
  public function validateForm(array &$form, FormStateInterface $form_state)
  {
    $form_values = $form_state->getValues();

    if (!preg_match('/^(([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\-]*[a-zA-Z0-9])\.)+([A-Za-z0-9]|[A-Za-z0-9][A-Za-z0-9\-]*[A-Za-z0-9])$/', $form_values['domain'])) {
      $form_state->setErrorByName('domain', t('Please enter a valid domain name.'));
      return FALSE;
    }
    return TRUE;
  }//end validateForm()

  /**
   * {@inheritdoc}
   */
  public function submitForm(array &$form, FormStateInterface $form_state)
  {
    global $base_url;

    $domain = $form_state->getValue('domain');
    if (mailjet_user_domain_add($domain)) {
      \Drupal::messenger()->addMessage(
        t(
          'Your domain @domain has successfully been added to Mailjet.
      To confirm domain ownership you must create an empty text file and place it in the root folder of the website.
      The file name is shown in the table below on the same line as your newly added domain.',
          [
            '@domain' => $domain,
          ]
        )
      );

      $response = new RedirectResponse($base_url . '/admin/config/system/mailjet/domains');
      $response->send();
    } else {
      return FALSE;
    }
  }//end submitForm()

}//end class