# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
#
# This Source Code Form is "Incompatible With Secondary Licenses", as
# defined by the Mozilla Public License, v. 2.0.

package Bugzilla::Extension::SecureMail::TCT;
use 5.10.1;
use Moo;

use Bugzilla::DaemonControl qw( on_finish on_exception );
use File::Temp;
use Future::Utils qw(call);
use Future;
use IO::Async::Process;

has 'public_key'      => (is => 'ro', required => 1);
has 'public_key_file' => (is => 'lazy');
has 'is_valid'        => (is => 'lazy');
has 'command'         => (is => 'ro', default => 'tct');

sub _build_public_key_file {
  my ($self) = @_;
  my $fh = File::Temp->new(SUFFIX => '.pubkey');
  $fh->print($self->public_key);
  $fh->close;
  return $fh;
}

sub _build_is_valid {
  my ($self) = @_;

  my $loop   = IO::Async::Loop->new;
  my $exit_f = $loop->new_future;
  my ($stderr, $stdout);
  my $process = IO::Async::Process->new(
    command      => [$self->command, 'check', '-k', $self->public_key_file],
    stderr       => {into => \$stderr,},
    stdout       => {into => \$stdout,},
    on_finish    => on_finish($exit_f),
    on_exception => on_exception($self->command, $exit_f),
  );
  $loop->add($process);

  return $exit_f->then(sub {
    my ($rv) = @_;
    Future->wrap($rv == 0);
  });
}

sub encrypt {
  my ($self, $input, $comment) = @_;
  $self->is_valid->then(sub {
    my ($is_valid) = @_;
    call {
      die 'invalid public key!' unless $is_valid;

      my $output;
      my $loop    = IO::Async::Loop->new;
      my $exit_f  = $loop->new_future;
      my @command = ($self->command, 'encrypt', '-k', $self->public_key_file);
      push @command, '--comment', $comment if $comment;
      my $process = IO::Async::Process->new(
        command      => \@command,
        stdin        => {from => $input,},
        stdout       => {into => \$output,},
        on_finish    => on_finish($exit_f),
        on_exception => on_exception($self->command, $exit_f),
      );
      $loop->add($process);

      return $exit_f->then(sub { Future->wrap($output) });
    }
  });
}

1;

__END__

=head1 NAME

Bugzilla::Extension::SecureMail::TCT - An interface to the tct program

=head1 SYNOPSIS

    my $key = <<'PUBLIC_KEY';
    -----BEGIN PGP PUBLIC KEY BLOCK-----

    mQINBFakJSsBEACbDwHztgZaVhIb6f4PN0KbXv5BEciqKNbdVLgWQJyqgEMIwTF7
    ...
    o858gRM=
    =t9lA
    -----END PGP PUBLIC KEY BLOCK-----
    PUBLIC_KEY

    my $tct = Bugzilla::Extension::SecureMail::TCT->new(public_key => $key);
    my $encrypted = $tct->encrypt("message", "comment goes here")->get;