Thank you, we figured out that we can read vmf file and get light information from there.
Angles and position were with an offset, so we used transforms from WW and other information from VMF file directly.
However, we still need to figure out offsets of intensity and radius of lights, because Source, 3ds max or Maya and Unity light systems are not the same, hence values cannot be exactly the same.
But somehow I feel that there will be no direct conversion, therefore I will use some scalar for light intensity and radius to get approximate result (Source to Unity).