The wiring is partialy there. There's a multiplug behind the bumper that does other functions with the front fog wiring, but the wiring harness from the multiplug to the fog lamps is not there.
The switch just needs plugging in , then enabling in the body control module using either foccuus software or forscan software( both free downloads) using a laptop and an elm327 adapter.
Basically I would go to a scrapyard and obtain the switch,fog lamps and chrome surrounds with the wiring harness .
I have done this with new parts for a customer a few years ago