UNO to emulate bluetooth headset for google now

So I want to have my arduino with a bluetooth module connect to my android phone as a bluetooth headset.

The only reason I want to do this is to have an external mic to say "ok, google" into. I.e. mic and bluetooth module connected to UNO, then pair with android, say ok google into mic and then whatever voice command. Is this possible?, if so, how would I go about doing it?