SetParametersGroupChild::getRequestFields

private function getRequestFields(HttpRequest $request): ?array
{
	$controls = $request->getPost('controls');
	if (!is_array($controls))
	{
		return null;
	}

	$fieldName = $controls[self::getId()] ?? null;
	$fieldValue = $controls[$fieldName] ?? null;
	if (empty($fieldName) || !is_string($fieldName) || !isset($fieldValue))
	{
		return null;
	}
	elseif (!$this->isAvailableField($fieldName))
	{
		return null;
	}

	$fields = [
		$fieldName => $fieldValue,
	];

	if ($fieldName !== 'PURCHASING_PRICE')
	{
		return $fields;
	}

	$fieldValue =  $controls['PURCHASING_CURRENCY'] ?? null;
	if (empty($fieldValue) || !is_string($fieldValue))
	{
		return null;
	}
	$fields['PURCHASING_CURRENCY'] = $fieldValue;

	return $fields;
}