Common or Thrush Nightingale or something else?

I came across this bird by the side of the coast path in Pembrokeshire today. It did not fly or even attempt to escape but initially carried on grubbing through the leaf litter. I did not stay long to prevent stress to the bird but just took a quick shot with my phone and then left it alone. It also spread out its wings rather like when a bird is anting showing the wings were the same colours in the photo (eg no white or other patches). Its not a location I would expect to see either of the species I mention but the airflow has been a strong northerly one in recent days.