#!/usr/bin/perl -w
#
# paper token is a software to generate paper-based OTP
#
# Copyright (C) 2010 Alexandre Dulaunoy, http://www.foo.be/
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License

use Authen::HOTP qw(hotp);
use PDF::API2;
use PDF::Table;
use Data::Dumper;
use Getopt::Compact;

# default value is the test vector from RFC 4226
my $secret = "3132333435363738393031323334353637383930";

# starting counter
my $counter = 0;

# ending counter
my $end = 500;

my $digits     = 6;
my @tokentable = [];

# window value (shown on one line and window of accepted token)
my $window = 14;

my $when = localtime();

my $opt = new Getopt::Compact(
    name    => 'paper token - http://www.foo.be/paper-token/',
    modes   => '',
    version => '0.1',
    struct  => [
        [
            [qw(s secret)],
qq(secret of the token in hex format - default is RFC 4226 test vector),
            ':s'
        ],
        [ [qw(o output)],  qq(output filename),                 ':s' ],
        [ [qw(c counter)], qq(starting counter - default is 0), ':i' ],
        [ [qw(e end)],     qq(ending counter - default is 500), ':i' ],
        [
            [qw(w window)],
            qq(window of authentication (one line) - default is 14), ':i'
        ],
        [
            [qw(d digits)],
            qq(digits showed per OTP value - default is 6 - dec31.6), ':i'
        ],
    ]
);

my $opts = $opt->opts;

if ( !( defined( $opts->{output} ) ) ) {
    print $opt->usage;
    exit();
}

if ( defined( $opts->{counter} ) ) {
    $counter = $opts->{counter};
}

if ( defined( $opts->{end} ) ) {
    $end = $opts->{end};
}

if ( defined( $opts->{window} ) ) {
    $window = $opts->{window};
}

if ( defined( $opts->{secret} ) ) {
    $secret = $opts->{secret};
}

my $sn = substr( $secret, 0, 10 );

if ( defined( $opts->{digits} ) ) {
    $digits = $opts->{digits};
}

for ( $count = $counter ; $count < $counter + $end ; $count = $count + $window )
{
    my @tj;
    for ( $j = $count ; $j < $count + $window ; $j = $j + 1 ) {
        my $pass = hotp( $secret, $j, $digits );
        push( @tj, "$pass" );
    }
    @val = ["@tj"];
    push( @{ $tokentable[0] }, @val );
}

my $pdftable = new PDF::Table;
my $pdf      = new PDF::API2( -file => $opts->{output} );
my $page     = $pdf->page;
my $gfx      = $page->gfx;

my $tokeninfo = "Paper token for HOTP token S/N : " . $sn;
my $tokenhowto =
"How to use? Read from left to right and when you use a token, strikethrough the used value.";
my $tokenadv =
  "Generated by paper token - http://www.foo.be/paper-token/ at " . $when;

$pdf->info(
    'Author'   => "Alexandre Dulaunoy - http://www.foo.be/",
    'Creator'  => "Paper Token - http://www.foo.be/paper-token/",
    'Producer' => "PDF::API2",
    'Title'    => $tokeninfo,
);

$fnt    = $pdf->corefont('Helvetica-Bold');
$fntlow = $pdf->corefont('Helvetica');

$gfx->textlabel( 10, 750, $fnt,    11, $tokeninfo );
$gfx->textlabel( 10, 739, $fntlow, 11, $tokenhowto );
$gfx->textlabel( 10, 728, $fntlow, 11, $tokenadv );

$pdftable->table(
    $pdf,
    $page,
    @tokentable,
    -x                     => 1,
    -w                     => 40,
    -start_y               => 700,
    -next_y                => 700,
    -start_h               => 700,
    -next_h                => 700,
    -w                     => 600,
    -padding               => 2,
    -padding_right         => 1,
    -background_color_odd  => "lightgray",
    -background_color_even => "gray",
    font      => $pdf->corefont( "Helvetica", -encoding => "utf8" ),
    font_size => 11,
    border    => 0
);

$pdf->save();