Need IRule to insert GeoIP into XFF

I'm trying to implement the new GeoIP feature on my LTM and want to insert all GeoIP information available into the XFF header. Here is my code so far but I need to add, continent, country and state as well. Any help would be appreciated:

when HTTP_REQUEST { if {[HTTP::header exists X-Forwarded-For]}{ HTTP::header replace X-Forwarded-For "[HTTP::header X-Forwarded-For], [IP::client_addr]" } else { HTTP::header insert X-Forwarded-For [IP::client_addr] } }