function.php

private function generateRedirectUrl(Order $order): ?string
{
    if (! $order->isPaymentTypeBank()) {
        return null;
    }

    $requestUri = [
        'lang_code'  => config('project.payments.merchant.lang_code'),
        'merch_id'   => config('project.payments.merchant.merch_id'),
        'o.order_id' => $order->getId(),
    ];

    $locale = app()->getLocale();
    if ($order->isClientPlatformMobile()) {
        $requestUri['back_url_s'] = $this->replaceLocaleMarker(
            (string) config('project.payments.redirect.mobile.success'),
            $locale,
        );
        $requestUri['back_url_f'] = $this->replaceLocaleMarker(
            (string) config('project.payments.redirect.mobile.fail'),
            $locale,
        );
    } else {
        $requestUri['back_url_s'] = $this->replaceLocaleMarker(
            (string) config('project.payments.redirect.web.success'),
            $locale,
        );
        $requestUri['back_url_f'] = $this->replaceLocaleMarker(
            (string) config('project.payments.redirect.web.fail'),
            $locale,
        );
    }

    $redirectUrl = config('project.payments.merchant.url') . '?' . http_build_query($requestUri);

    return $redirectUrl;
}