Logic in Calculations Field

Hi there,
is there a way to insert some logic inside Calculations Field?

I have a form for a registration to some courses and there are some discount possibilities that I handle with Radio buttons.

At the moment this is my rule for Calculations but I need to handle a second Radio as multiplier.
(({select-1} + {select-3}) * 3 ) * {radio-2} + {radio-1}

I would really like it could be like this:
IF ({radio-3} > 0)
(({select-1} + {select-3}) * 3 ) * {radio-3} + {radio-1}
ELSE
(({select-1} + {select-3}) * 3 ) * {radio-2} + {radio-1}
END IF

Or eventually this would be better:
(({select-1} + {select-3}) * 3 ) * MIN({radio-2};{radio-3}) + {radio-1}

Another way could be something like the Visibility Logic for Calculations with an OR condition like the following:
Calulations:
– RULE 1 –> Calculations 1 -OR-
– RULE 2 –> Calculations 2 -OR-
– RULE 3 –> Calculations 3 …

Give some LOVE to Calculations! ??

Giandani