iRule for handling xml and html requests

Hi, I want to write an irule which handles both xml and html requests. Whenever an attack signature is triggered, iRule should respond with html response for html requests and XML response for XML requests along with the support id. Please note that I am not using the option provided for XML page in the ASM because for that, XML page needs to be mapped to the XML profile, and here which page would be XML is unknown. The only reliability is on the content-type header.