#!/usr/bin/perl -w

# This script searches for a pattern similar to this:
#   <br/>
#   <br/>
#   <dt><b>BIO 110 Biology Seminar</b></dt>
#   <dd> 
#   This offering serves to introduce the majors to the broad field of biological 
#   sciences through seminars and discussions focusing on current subject areas, 
#   approaches and techniques used by scientists to understand the living world. 
#   Specific content will vary depending on instructor. Fl, Sp-1-</dd>
#   <br/>
#   <br/>

use 5.004;
use Getopt::Std qw(&getopts);

use subs qw(&bail);
use vars qw($opt_d $DEBUG);
use vars qw($file @files);
use vars qw($contents @contents);
use vars qw(@courses);
local (*FILE);

   $DEBUG = 0;
   if (!getopts('-d')) {
      &bail("invalid arguments");
   }
   if (defined $opt_d) {
      $DEBUG = 1;
   }
   if ($#ARGV < 0) {
      &bail("usage:: " . $0 . " file [ file ... ]\n");
   }
   @files = @ARGV;

   if ($DEBUG > 0) {
      print STDOUT "starting with file $files[0]\n";
   }

   foreach $file (@files) {
      if ($DEBUG > 0) {
         print STDOUT "processing $file\n";
      }

      if (!(open FILE, "<$file")) {
         warn "can't open $file\n";
         next;
      }
      @contents = <FILE>;
      close FILE;
      @contents || next;
      $contents = join "", @contents;
      # print $contents;
      @courses = split m#<br ?/?>\n?<br ?/?># , $contents;
      foreach my $course (@courses) {
        my $t1 = $course =~ /global/i;
        my $t2 = $course =~ /sustain/i;
        my $t3 = $course =~ /warm/i;
        my $t4 = $course =~ /earth/i;
        if ($t1 || $t2 || $t3 || $t4) {
          print "$course";
        }
        print "---------------------------\n";
      }
      exit 0;

   }

   exit 0;

sub bail
{
   my $error = "@_";
   print "$error\n";
   exit 1;
}