protected function normalizeValues(array $values, string $property): ?array
    {
        foreach ($values as $key => $value) {
            if (!\is_int($key) || !\is_string($value)) {
                unset($values[$key]);
            }
        }

        if (empty($values)) {
            $this->getLogger()->notice('Invalid filter ignored', [
                'exception' => new InvalidArgumentException(sprintf('At least one value is required, multiple values should be in "%1$s[]=firstvalue&%1$s[]=secondvalue" format', $property)),
            ]);

            return null;
        }

        return array_values($values);
    }