#!/usr/bin/perl

use POSIX;
use strict;

my %months;

$months{"jan"} = 0;
$months{"feb"} = 1;
$months{"mar"} = 2;
$months{"apr"} = 3;
$months{"may"} = 4;
$months{"jun"} = 5;
$months{"jul"} = 6;
$months{"aug"} = 7;
$months{"sep"} = 8;
$months{"oct"} = 9;
$months{"nov"} = 10;
$months{"dec"} = 11;

# are_dates_within_six_hours - Determine if two dates are within six hours
#
# usage: $boolean = are_dates_within_six_hours($date1, $date2);
#
# This function determines if two dates are within six hours of each
# other, and returns 1 or 0 accordingly.
#
# The dates are formatted as follows:
#
#    DD-Mnt-YY HH:MM:SS
#
#
# Which date is later or earlier does not matter.


sub are_dates_within_six_hours
{
        my ($date1, $date2) = @_;
        my @times;

        foreach($date1, $date2)
        {
                # Parse the date.
                my $day;
                my $month;
                my $year;
                my $hour;
                my $min;
                my $sec;

                if($_ =~ /(\d*)-([[:alpha:]]*)-(\d*)\s*(\d*):(\d*):(\d*)/)
                {
                        $day=$1;
                        $month = $months{lc $2};
                        $year=$3;
                        $hour=$4;
                        $min=$5;
                        $sec=$6;

                        # Horrible bug: The dates you're using use
                        #               two-digit years! I'll blindly
                        #               assume that all your dates
                        #               are in the 21st century or later.

                        $year += 100;
                }
                else
                {
                        die "$_: Does not conform to expected format\n";
                }

                # Convert the time into Unix's time_t value.
                push @times, mktime($sec, $min, $hour, $day, $month, $year);
        }

        # 21600 seconds in six hours.

        return (abs($times[0] - $times[1]) <= 21600);
}