I think your next step should be to create a hash of all possible inputs and responses.

%call_and_response = (

'yo',     'what\'s up',

'not much',     'cool',

'how about that local sports team?',     'they suck',

);
[download]

Then you can just do

if($call_and_response{$call}){
  print $call_and_response{$call};
}else{
  print "huh?";
}
[download]

or something like that.
--

“Every bit of code is either naturally related to the problem at hand, or else it's an accidental side effect of the fact that you happened to solve the problem using a digital computer.”
M-J D