# SPDX-License-Identifier: GPL-2.0-or-later

package Amavis::Unpackers::NewFilename;
use strict;
use re 'taint';

BEGIN {
  require Exporter;
  use vars qw(@ISA @EXPORT @EXPORT_OK %EXPORT_TAGS $VERSION);
  $VERSION = '2.412';
  @ISA = qw(Exporter);
  @EXPORT_OK = qw(&consumed_bytes);
}

use Amavis::Conf qw(c cr ca
                    $MIN_EXPANSION_QUOTA $MIN_EXPANSION_FACTOR
                    $MAX_EXPANSION_QUOTA $MAX_EXPANSION_FACTOR);
use Amavis::Util qw(ll do_log min max minmax);

use vars qw($avail_quota);  # available bytes quota for unpacked mail
use vars qw($rem_quota);    # remaining bytes quota for unpacked mail

sub new($;$$) {  # create a file name generator object
  my($class, $maxfiles,$mail_size) = @_;
  # calculate and initialize quota
  $avail_quota = $rem_quota =  # quota in bytes
    max($MIN_EXPANSION_QUOTA, $mail_size * $MIN_EXPANSION_FACTOR,
        min($MAX_EXPANSION_QUOTA, $mail_size * $MAX_EXPANSION_FACTOR));
  ll(4) && do_log(4,'Original mail size: %d; quota set to: %d bytes '.
                    '(fmin=%s, fmax=%s, qmin=%s, qmax=%s)',
                    $mail_size, $avail_quota,
                    map(defined $_ ? "$_" : 'UNDEF',
                        $MIN_EXPANSION_FACTOR, $MAX_EXPANSION_FACTOR,
                        $MIN_EXPANSION_QUOTA, $MAX_EXPANSION_QUOTA));
  # create object
  bless {
    num_of_issued_names => 0,  first_issued_ind => 1,  last_issued_ind => 0,
    maxfiles => $maxfiles,  # undef disables limit
    objlist => [],
  }, $class;
}

sub parts_list_reset($) {  # clear a list of recently issued names
  my $self = $_[0];
  $self->{num_of_issued_names} = 0;
  $self->{first_issued_ind} = $self->{last_issued_ind} + 1;
  $self->{objlist} = [];
}

sub parts_list($) {  # returns a ref to a list of recently issued names
  my $self = $_[0];
  $self->{objlist};
}

sub parts_list_add($$) {  # add a parts object to the list of parts
  my($self, $part) = @_;
  push(@{$self->{objlist}}, $part);
}

sub generate_new_num($$) {  # make-up a new number for a file and return it
  my($self, $ignore_limit) = @_;
  if (!$ignore_limit && defined($self->{maxfiles}) &&
      $self->{num_of_issued_names} >= $self->{maxfiles}) {
    # do not change the text in die without adjusting decompose_part()
    die "Maximum number of files ($self->{maxfiles}) exceeded";
  }
  $self->{num_of_issued_names}++; $self->{last_issued_ind}++;
  $self->{last_issued_ind};
}

sub consumed_bytes($$;$$) {
  my($bytes, $bywhom, $tentatively, $exquota) = @_;
  if (ll(4)) {
    my $perc = !$avail_quota ? '' : sprintf(", (%.0f%%)",
                 100 * ($avail_quota - ($rem_quota - $bytes)) / $avail_quota);
    do_log(4,"Charging %d bytes to remaining quota %d (out of %d%s) - by %s",
             $bytes, $rem_quota, $avail_quota, $perc, $bywhom);
  }
  if ($bytes > $rem_quota && $rem_quota >= 0) {
    # Do not modify the following signal text, it gets matched elsewhere!
    my $msg = "Exceeded storage quota $avail_quota bytes by $bywhom; ".
              "last chunk $bytes bytes";
    do_log(-1, "%s", $msg);
    die "$msg\n"  if !$exquota;   # die, unless allowed to exceed quota
  }
  $rem_quota -= $bytes  unless $tentatively;
  $rem_quota;  # return remaining quota
}

1;