package OATHusers;
#---AUTOPRAGMASTART---
use 5.012;
use strict;
use warnings;
use diagnostics;
use mro 'c3';
use English qw( -no_match_vars );
use Carp;
our $VERSION = 0.996;
#---AUTOPRAGMAEND---

use Authen::OATH;

sub new {
    my $class = shift;
    my $self = bless {}, $class;
    
    my %seeds = (
             'tye'      => {
                            key_id  => '000001',
                            pin     => '2412',
                            seed    => uc('aaaaaaaaabbbbbbbbbbbbbbccccccccccddddddd'),
                           },
             'browseruk'=> {
                            key_id  => '222222',
                            pin     => '4242',
                            seed    => uc('0101010101010101010101010101010101010101'),
                           },
             'reaper'   => {
                            key_id  => '9',
                            pin     => 'SIGKILL',
                            seed    => uc('1231231231231231231231231231231231231231'),
                           },
    );
    
    $self->{seeds} = \%seeds;
    
    return $self;
}

sub validate {
    my ($self, $username, $password) = @_;

    # Missing fields
    if(!defined($username) || !defined($password) ||
       $username eq '' || $password eq '') {
        return 0;
    }
    
    # Unknown username
    if(!defined($self->{seeds}->{$username})) {
        return 0;
    }
    
    # For the easy part: Check length of password
    if(length($password) != (length($self->{seeds}->{$username}->{pin}) + 6)) {
        return 0;
    }
    
    my $oath = Authen::OATH->new(timestep => 60);
    my $valid = 0;
    my $now = time;
    my $userseed = $self->{seeds}->{$username}->{seed};
    for(my $i = -300; $i <= 300; $i += 60) { # Search +/- 5 minutes
        my $totp = $oath->totp($userseed, $now + $i);
        my $fullpass = $self->{seeds}->{$username}->{pin} . $totp;
        if($fullpass eq $password) {
            print "$username key drift $i\n";
            $valid = 1;
            last;
        }
    }
    
    return $valid;
}


1;