#!/usr/bin/perl
#
# v1.0
# lastlogin.pl - Reports what users have not logged on in a specifed amount
#		 of time.
# Aaron W. Morris
# Options:  #h (hours), #d (days), #w (weeks), #m (months), #y (years)
# Example:  lastlogin.pl 3h 4d 8m 1y

use strict;

if(! @ARGV) {
	print "Usage:  \"lastlogin.pl 5d 2m 1y\"\n";
	exit 1;
}
my @periods = @ARGV;

my $ltime = time();

my $i = 0;
my $x = 0;
my $hour = 3600;
my $day = $hour * 24;
my $week = $day * 7;
my $month = $day * 30;
my $year = $day * 365;

my $run = $#periods + 1; 

#change args into seconds
my @times;
my $seconds;
while($run != 0) {
	if($periods[$i] =~ /^(\d{1,})(h|d|w|m|y)$/i) {
		$seconds = &getseconds($1,$2);
		$times[$x] = $seconds;
		$x++;
	}
	$i++;
	$run--;
}

my @stimes = &sorttimes(@times);

#read `lsuser ALL`
my %users;
my @lsuser = `/usr/sbin/lsuser ALL`;
foreach(@lsuser) {
	my $line = $_;
	my @items;
	my %userinfo;

	chomp $line;
	@items = split(/\s/,$line);

	%userinfo = &makehash(@items);
	
	$users{getpwuid($userinfo{'id'})} = $userinfo{'time_last_login'};
}

#process entries and assign to appropriate anonymous hashes
my $key;
my $value;
my $lastlog;
while( ($key,$value) = each(%users) ) {

	next if(! $value);

	for(0 .. $#stimes) {
		if($value <= ($ltime - $stimes[$_]) ) {
			$lastlog->{$stimes[$_]}->{$key} = $value;
			last;
		}
	}
}

#output info
my $anonref;
my $timeper;
for(0 .. $#stimes) {
	$timeper = &gettimeper($stimes[$_]);
	print "\n\n>$timeper\n";
	$anonref = $lastlog->{$stimes[$_]};
	while( ($key,$value) = each(%$anonref) ) {
		print "$key ";
	}
	print "\n";
}

print "\n";
#end

sub makehash {
	my @items = @_;
	my %infohash;
	my $element;
	my @info;

	foreach $element (@items) {
                @info = split(/\=/,$element);
                $infohash{$info[0]} = $info[1];
	}
	
	return %infohash;
} #end sub makehash

sub getseconds {
	my $numperiod = $_[0];
	my $per = $_[1];
	my $seconds;

	$per =~ tr/[A-Z]/[a-z]/;

	if($per eq "h") { $seconds = $hour; }
	elsif($per eq "d") { $seconds = $day; }
	elsif($per eq "w") { $seconds = $week; }
	elsif($per eq "m") { $seconds = $month; }
	elsif($per eq "y") { $seconds = $year; }

	return ($seconds * $numperiod);

} #end sub getseconds

sub sorttimes {
	my @times = @_;
	my $change = 1;


	until($change == 0){
		$change = 0;

		for(0 .. ($#times - 1)) {
			my $pos = $_;
			my $temp1;
			my $temp2;

			if($times[$pos] < $times[($pos + 1)]) {
				$temp1 = $times[$pos];
				$temp2 = $times[($pos + 1)];

				$times[$pos] = $temp2;
				$times[($pos + 1)] = $temp1;
	
				$change = 1;
			}
			elsif($times[$pos] == $times[($pos + 1)]) {
				splice(@times,$pos,1);
				@times = &sorttimes(@times);
				$change = 1;
				last;
			}
		}
	}

	return(@times);
} #end sub sorttimes

sub gettimeper {
	my $seconds = $_[0];
	my $message;
	my $howmany;

        if( ($seconds % $year) == 0 ) {
                $howmany = $seconds / $year;
                $message = $howmany . " Year(s)";
        }
        elsif( ($seconds % $month) == 0 ) {
                $howmany = $seconds / $month;
                $message = $howmany . " Month(s)";
        }
        elsif( ($seconds % $week) == 0 ) {
                $howmany = $seconds / $week;
                $message = $howmany . " Week(s)";
        }
        elsif( ($seconds % $day) == 0 ) {
                $howmany = $seconds / $day;
                $message = $howmany . " Day(s)";
        }
        elsif( ($seconds % $hour) == 0 ) {
                $howmany = $seconds / $hour;
                $message = $howmany . " Hour(s)";
        }


	return($message);
} #end sub gettimeper