#!/usr/local/bin/perl
#############################################################################
#  Programmer : Bridget Thomson McInnes
#  
#  Description:  A small program to simulate a Rogerian Psycotherapist.
#                Based off the Eliza program by Weizenbaum (1960).
#
#  Usage:
#             perl doctor.pl
#
#  Note:
#           this program badly lacks comments
#
##############################################################################
print "The doctor is in the house, what seems to be the problem?\n\n";

while(<STDIN>) {
    chomp;
    
    $_ = lc($_);

    $_ =~s/[.!?,]//g;

    $_ =~s/\bI am\b/why are you/;

    $_ =~s/my\b ([a-zA-Z]+) is/why is your $1/i;

    $_ =~s/\bme\b/you/gi;
    
    $_ =~s/i\b/you/gi;   

    $_ =~s/my\b/your/gi;
    
    $_ =~s/am\b/are/gi;
 
    $_ =~s/([A-Za-z]+\s)*\b?because\b(\s[A-Za-z]+)*/this seems to pose a problem, what do you think we should do about it?/i;
    
    $_ =~s/([A-Za-z]+\s)*\b?no\b(\s[A-Za-z]+)*/does this make you mad?/i;

    $_ =~s/([A-Za-z]+\s)*\b?yes\b(\s[A-Za-z]+)*/tell me why./i;
    
    $_ =~s/([A-Za-z]+\s)*\b?(kick|ass|jerk)\b(\s[A-Za-z]+)*/this is not a very grown up way to handle problems./i;
    
    $line = $_;

    if($line=~m/[.?!]/){ ; } else { $line .= "?"; } 
   
    print "\n$line\n\n";
}