I see you have HID driving lights. May I ask where you got these?? It's H7 for the 159 dipped isn't it??
Yes, the dipped beam are H7's. I had them installed at the garage I bought the car from (Veloces of London) so not sure where they sourced them from, but any modern H7 Can Bus Friendly set should be just fine. I have installed HIDs in other cars and found eBay the only place you ever need to go to find what you need.
Only advice I would give on HIDs is:
1) Get 4300K or 4500K as higher rated colours are too blue / purple and attract the rozzers.
2) Get 35w not the new 55w ones as they are way too bright and again, attract the wrong attention.
For me, the idea is to make the HIDs look as factory fitted as possible as technically they are illegal for road use unless fitted by the factory, along with a headlight levelling system, headlight washers, & projector lenses. As the 159 has projectors, you get away with it, as this keeps the beam alignment good and out of oncoming traffic, and at first glance you don't notice the lack of washer jets etc.
I have had a previous car MOT'd with after market HIDs on and it passed, but worst case scenario, you would have to disconnect them and put standard bulbs back in for the MOT.
The legislation on HIDs in the UK is here FYI:
Aftermarket HID (Xenon) headlamps
Although some of their reasoning is sound enough, as long as your not chaving it up with 6500K 55w units bolted onto your corsa's standard headlights, your not going to blind oncoming traffic.