#!/usr/bin/perl
# Exercise base64.

# Copyright (C) 2006-2013 Free Software Foundation, Inc.

# 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
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

use strict;

(my $program_name = $0) =~ s|.*/||;

# Turn off localization of executable's output.
@ENV{qw(LANGUAGE LANG LC_ALL)} = ('C') x 3;

# Return the encoding of a string of N 'a's.
sub enc($)
{
  my ($n) = @_;
  my %remainder = ( 0 => '', 1 => 'YQ==', 2 => 'YWE=' );
  return 'YWFh' x ($n / 3) . $remainder{$n % 3};
}

# Construct an encoded string of length 4KB, using 3K "a"s.
my $a3k = enc 3072;
my @a3k_nl;
# A few copies, each with different number of newlines at the start.
for my $k (0..3)
  {
    (my $t = $a3k) =~ s/^/"\n"x $k/e;
    push @a3k_nl, $t;
  }

# Return a copy of S, with newlines inserted every WIDTH bytes.
# Ensure that the result (if not the empty string) is newline-terminated.
sub wrap($$)
{
  my ($s, $width) = @_;
  $s =~ s/(.{$width})/$1\n/g;
  substr ($s, -1, 1) ne "\n"
    and $s .= "\n";
  return $s;
}

my @Tests =
    (
     ['empty', {IN=>''}, {OUT=>""}],
     ['inout', {IN=>'a'}, {OUT=>"YQ==\n"}],
     ['wrap', '--wrap 0', {IN=>'foo'}, {OUT=>'Zm9v'}],
     ['wrap5-39', '--wrap=5', {IN=>'a' x 39}, {OUT=>wrap enc(39),5}],
     ['wrap5-40', '--wrap=5', {IN=>'a' x 40}, {OUT=>wrap enc(40),5}],
     ['wrap5-41', '--wrap=5', {IN=>'a' x 41}, {OUT=>wrap enc(41),5}],
     ['wrap5-42', '--wrap=5', {IN=>'a' x 42}, {OUT=>wrap enc(42),5}],
     ['wrap5-43', '--wrap=5', {IN=>'a' x 43}, {OUT=>wrap enc(43),5}],
     ['wrap5-44', '--wrap=5', {IN=>'a' x 44}, {OUT=>wrap enc(44),5}],
     ['wrap5-45', '--wrap=5', {IN=>'a' x 45}, {OUT=>wrap enc(45),5}],
     ['wrap5-46', '--wrap=5', {IN=>'a' x 46}, {OUT=>wrap enc(46),5}],

     ['buf-1',   '--decode', {IN=>enc 1}, {OUT=>'a' x 1}],
     ['buf-2',   '--decode', {IN=>enc 2}, {OUT=>'a' x 2}],
     ['buf-3',   '--decode', {IN=>enc 3}, {OUT=>'a' x 3}],
     ['buf-4',   '--decode', {IN=>enc 4}, {OUT=>'a' x 4}],
     # 4KB worth of input.
     ['buf-4k0', '--decode', {IN=>enc 3072+0}, {OUT=>'a' x (3072+0)}],
     ['buf-4k1', '--decode', {IN=>enc 3072+1}, {OUT=>'a' x (3072+1)}],
     ['buf-4k2', '--decode', {IN=>enc 3072+2}, {OUT=>'a' x (3072+2)}],
     ['buf-4k3', '--decode', {IN=>enc 3072+3}, {OUT=>'a' x (3072+3)}],
     ['buf-4km1','--decode', {IN=>enc 3072-1}, {OUT=>'a' x (3072-1)}],
     ['buf-4km2','--decode', {IN=>enc 3072-2}, {OUT=>'a' x (3072-2)}],
     ['buf-4km3','--decode', {IN=>enc 3072-3}, {OUT=>'a' x (3072-3)}],
     ['buf-4km4','--decode', {IN=>enc 3072-4}, {OUT=>'a' x (3072-4)}],

     # Exercise the case in which the final base-64 byte is
     # in a buffer all by itself.
     ['b4k-1',   '--decode', {IN=>$a3k_nl[1]}, {OUT=>'a' x (3072+0)}],
     ['b4k-2',   '--decode', {IN=>$a3k_nl[2]}, {OUT=>'a' x (3072+0)}],
     ['b4k-3',   '--decode', {IN=>$a3k_nl[3]}, {OUT=>'a' x (3072+0)}],

     ['baddecode', '--decode', {IN=>'a'}, {OUT=>""},
      {ERR_SUBST => 's/.*: invalid input//'}, {ERR => "\n"}, {EXIT => 1}],
     ['baddecode2', '--decode', {IN=>'ab'}, {OUT=>"i"},
      {ERR_SUBST => 's/.*: invalid input//'}, {ERR => "\n"}, {EXIT => 1}],
     ['baddecode3', '--decode', {IN=>'Zzz'}, {OUT=>"g<"},
      {ERR_SUBST => 's/.*: invalid input//'}, {ERR => "\n"}, {EXIT => 1}],
     ['baddecode4', '--decode', {IN=>'Zz='}, {OUT=>"g"},
      {ERR_SUBST => 's/.*: invalid input//'}, {ERR => "\n"}, {EXIT => 1}],
     ['baddecode5', '--decode', {IN=>'Z==='}, {OUT=>""},
      {ERR_SUBST => 's/.*: invalid input//'}, {ERR => "\n"}, {EXIT => 1}]
    );

# For each non-failing test, create a --decode test using the
# expected output as input.  Also, add tests inserting newlines.
my @new;
foreach my $t (@Tests)
  {
    my $exit_val;
    my $in;
    my @out;

    # If the test has a single option of "--decode", then skip it.
    !ref $t->[1] && $t->[1] eq '--decode'
      and next;

    foreach my $e (@$t)
      {
        ref $e && ref $e eq 'HASH'
          or next;
        defined $e->{EXIT}
          and $exit_val = $e->{EXIT};
        defined $e->{IN}
          and $in = $e->{IN};
        if (defined $e->{OUT})
          {
            my $t = $e->{OUT};
            push @out, $t;
            my $len = length $t;
            foreach my $i (0..$len)
              {
                my $u = $t;
                substr ($u, $i, 0) = "\n";
                push @out, $u;
                10 <= $i
                  and last;
              }
          }
      }
    $exit_val
      and next;

    my $i = 0;
    foreach my $o (@out)
      {
        push @new, ["d$i-$t->[0]", '--decode', {IN => $o}, {OUT => $in}];
        ++$i;
      }
  }
push @Tests, @new;

my $save_temps = $ENV{DEBUG};
my $verbose = $ENV{VERBOSE};

my $prog = 'base64';
my $fail = run_tests ($program_name, $prog, \@Tests, $save_temps, $verbose);
exit $fail;
