class Message

class Message extends ContentEntityBase implements MessageInterface {
  
  /**
   * {@inheritdoc}
   */
  public function isPersonal() {
    return $this->bundle() == 'personal';
  }
  
  /**
   * {@inheritdoc}
   */
  public function getContactForm() {
    return $this->get('contact_form')->entity;
  }
  
  /**
   * {@inheritdoc}
   */
  public function getSenderName() {
    return $this->get('name')->value;
  }
  
  /**
   * {@inheritdoc}
   */
  public function setSenderName($sender_name) {
    $this->set('name', $sender_name);
  }
  
  /**
   * {@inheritdoc}
   */
  public function getSenderMail() {
    return $this->get('mail')->value;
  }
  
  /**
   * {@inheritdoc}
   */
  public function setSenderMail($sender_mail) {
    $this->set('mail', $sender_mail);
  }
  
  /**
   * {@inheritdoc}
   */
  public function getSubject() {
    return $this->get('subject')->value;
  }
  
  /**
   * {@inheritdoc}
   */
  public function setSubject($subject) {
    $this->set('subject', $subject);
  }
  
  /**
   * {@inheritdoc}
   */
  public function getMessage() {
    return $this->get('message')->value;
  }
  
  /**
   * {@inheritdoc}
   */
  public function setMessage($message) {
    $this->set('message', $message);
  }
  
  /**
   * {@inheritdoc}
   */
  public function copySender() {
    return (bool) $this->get('copy')->value;
  }
  
  /**
   * {@inheritdoc}
   */
  public function setCopySender($inform) {
    $this->set('copy', (bool) $inform);
  }
  
  /**
   * {@inheritdoc}
   */
  public function getPersonalRecipient() {
    if ($this->isPersonal()) {
      return $this->get('recipient')->entity;
    }
  }
  
  /**
   * {@inheritdoc}
   */
  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
    /** @var \Drupal\Core\Field\BaseFieldDefinition[] $fields */
    $fields = parent::baseFieldDefinitions($entity_type);
    $fields['contact_form']->setLabel(t('Form ID'))
      ->setDescription(t('The ID of the associated form.'));
    $fields['uuid']->setDescription(t('The message UUID.'));
    $fields['langcode']->setDescription(t('The message language code.'));
    $fields['name'] = BaseFieldDefinition::create('string')->setLabel(t("The sender's name"))
      ->setDescription(t('The name of the person that is sending the contact message.'));
    $fields['mail'] = BaseFieldDefinition::create('email')->setLabel(t("The sender's email"))
      ->setDescription(t('The email of the person that is sending the contact message.'));
    // The subject of the contact message.
    $fields['subject'] = BaseFieldDefinition::create('string')->setLabel(t('Subject'))
      ->setRequired(TRUE)
      ->setSetting('max_length', 100)
      ->setDisplayOptions('form', [
      'type' => 'string_textfield',
      'weight' => -10,
    ])
      ->setDisplayConfigurable('form', TRUE);
    // The text of the contact message.
    $fields['message'] = BaseFieldDefinition::create('string_long')->setLabel(t('Message'))
      ->setRequired(TRUE)
      ->setDisplayOptions('form', [
      'type' => 'string_textarea',
      'weight' => 0,
      'settings' => [
        'rows' => 12,
      ],
    ])
      ->setDisplayConfigurable('form', TRUE)
      ->setDisplayOptions('view', [
      'type' => 'string',
      'weight' => 0,
      'label' => 'above',
    ])
      ->setDisplayConfigurable('view', TRUE);
    $fields['copy'] = BaseFieldDefinition::create('boolean')->setLabel(t('Copy'))
      ->setDescription(t('Whether to send a copy of the message to the sender.'));
    $fields['recipient'] = BaseFieldDefinition::create('entity_reference')->setLabel(t('Recipient ID'))
      ->setDescription(t('The ID of the recipient user for personal contact messages.'))
      ->setSetting('target_type', 'user');
    return $fields;
  }

}