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;
    }

}