ScheduleForm::deleteDuplicatesBetween

private function deleteDuplicatesBetween($firstFieldName, $secondFieldName)
{
	$bothAreNotEmptyArrays = !empty($this->{$firstFieldName}) && !empty($this->{$secondFieldName})
							 && is_array($this->{$firstFieldName}) && is_array($this->{$secondFieldName});
	if (!$bothAreNotEmptyArrays)
	{
		return;
	}

	$duplicates = array_intersect($this->{$firstFieldName}, $this->{$secondFieldName});
	if (empty($duplicates))
	{
		return;
	}
	$this->deleteDuplicatesFromArray($firstFieldName, $duplicates);
	$this->deleteDuplicatesFromArray($secondFieldName, $duplicates);
}