#!/usr/bin/perl
use strict;
use warnings;

my @lines = (
    't13:45\n',         'D13:45\n',
    'S13:45 Unicorn\n', 'D13:45\n',
    'S13:45\n',         'T13:45\n',
    't13:45\n',         'D13:45\n',
    'T13:46\n',         't13:45\n',
    'D13:45\n',         'S13:45\n',
    'D13:45\n',         'S13:45 UNICORN\n',
    'T13:45\n',         't13:45\n',
    'D13:45\n',         'T13:46\n'
);
my $value      = "unicorn";
my $newsection = 0;
my $debug      = 0; # Set to 1 for verbosity
my @section;

print "Let's start\n" if $debug;
while (my $row = shift (@lines)) {

    if ($newsection <= 0) {
        if ($row =~ /^t/) {
            print "New section started\n"       if $debug;
            print "Inserting $row into array\n" if $debug;
            push (@section, $row);
        } elsif ($row =~ /^[JSD]/) {
            print "Section continued\n" if $debug;
            push (@section, $row);
        } elsif ($row =~ /^T/) {
            print "Section Ended\n" if $debug;
            push (@section, $row);
            $newsection = 1;
        }
    }
    if ($newsection > 0) {
        $newsection = 0;
        print "Checking for value\n" if $debug;
        if (grep (/$value/i, @section)) {
            print "Value discovered, saving section\n" if $debug;
            print "$_\n" for @section;
        }
        @section = ();
    }
}