use MagentoCustomerModelContext as CustomerContext;
use MagentoCustomerModelContext;
use MagentoFrameworkAppHttpContext as HttpContext;

/**
 * @param HttpContext $httpContext
 */
public function __construct(HttpContext $httpContext)
{
    $this->httpContext = $httpContext;
}


/**
 * @return bool
 */
private function isLoggedIn()
{
    return (bool)$this->httpContext->getValue(Context::CONTEXT_AUTH);
}

if (null === $customerId) {
        if ($this->httpContext->getValue(CustomerContext::CONTEXT_AUTH)) {
            if (!$this->session->isSessionExists()) {
                $this->session->start();
            }

            $visitorData = $this->session->getData('visitor_data');
            if (isset($visitorData['customer_id'])) {
                $customerId = $visitorData['customer_id'];
            }
        }
    }