System Variable to fetch the URL of the Active SmartForm

There are situations when same K2 site is hosted on internal and external platforms into production. But, to identify the current URL at runtime is not possible as of now. Using JavaScript has been an option but it doesn't assign the value to a data label which can further be used. Hence, to have a system variable through which we can identify the current URL would be very convenient and can solve the issues we are stuck with.