cx-newsletter/components/06-plugin_settings.php

<?php

namespace cx_newsletter;
use \exception;

class plugin_settings
extends settings
implements settings_interface {
    protected function get_options() : array {
        return [
            'source_address' => '[email protected]',
            'reply_to_address' => '[email protected]',
            'email_count' => '50',
            'sms_count' => '10',
            'database_version' => 'null',
            'apikey' => 'CHANGE_ME_CHANGE_IT_PLEASE',
            'custom_smtp' => 'false',
            'smtp_address' => 'smtp.example.com',
            'smtp_port' => '465',
            'smtp_user' => 'example',
            'smtp_password' => 'QWERTY1234'
        ];
    }

    public function use_custom_smtp() : bool {
        return $this->get('custom_smtp') === 'true';
    }

    public function get_plugin_version() : int {
        return 2;
    }   
}