use v5.12.0;
use warnings;
package Email::MIME::Header 1.954;
# ABSTRACT: the header of a MIME message

use parent 'Email::Simple::Header';

use Carp ();
use Email::MIME::Encode;
use Encode 1.9801;
use Module::Runtime ();

our @CARP_NOT;

our %header_to_class_map;

BEGIN {
  my @address_list_headers = qw(from sender reply-to to cc bcc);
  push @address_list_headers, map { "resent-$_" } @address_list_headers;
  push @address_list_headers, map { "downgraded-$_" } @address_list_headers; # RFC 5504
  push @address_list_headers, qw(original-from disposition-notification-to); # RFC 5703 and RFC 3798
  $header_to_class_map{$_} = 'Email::MIME::Header::AddressList' foreach @address_list_headers;
}

#pod =head1 DESCRIPTION
#pod
#pod This object behaves like a standard Email::Simple header, with the following
#pod changes:
#pod
#pod =for :list
#pod * the C<header> method automatically decodes encoded headers if possible
#pod * the C<header_as_obj> method returns an object representation of the header value
#pod * the C<header_raw> method returns the raw header; (read only for now)
#pod * stringification uses C<header_raw> rather than C<header>
#pod
#pod Note that C<header_set> does not do encoding for you, and expects an
#pod encoded header.  Thus, C<header_set> round-trips with C<header_raw>,
#pod not C<header>!  Be sure to properly encode your headers with
#pod C<Encode::encode('MIME-Header', $value)> before passing them to
#pod C<header_set>.  And be sure to use minimal version 2.83 of Encode
#pod module due to L<bugs in MIME-Header|Encode::MIME::Header/BUGS>.
#pod
#pod Alternately, if you have Unicode (character) strings to set in headers, use the
#pod C<header_str_set> method.
#pod
#pod =cut

sub header_str {
  my $self  = shift;
  my $wanta = wantarray;

  return unless defined $wanta; # ??

  my @header = $wanta ? $self->header_raw(@_)
                      : scalar $self->header_raw(@_);

  foreach my $header (@header) {
    next unless defined $header;
    next unless $header =~ /=\?/;

    _maybe_decode($_[0], \$header);
  }
  return $wanta ? @header : $header[0];
}

sub header {
  my $self = shift;
  return $self->header_str(@_);
}

sub header_str_set {
  my ($self, $name, @vals) = @_;

  my @values = map {
    Email::MIME::Encode::maybe_mime_encode_header($name, $_, 'UTF-8')
  } @vals;

  $self->header_raw_set($name => @values);
}

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

  my @pairs = $self->header_pairs;
  for (grep { $_ % 2 } (1 .. $#pairs)) {
    _maybe_decode($pairs[$_-1], \$pairs[$_]);
  }

  return @pairs;
}

sub header_as_obj {
  my ($self, $name, $index, $class) = @_;

  $class //= $self->get_class_for_header($name);

  {
    local @CARP_NOT = qw(Email::MIME);
    local $@;
    Carp::croak("No class for header '$name' was specified") unless defined $class;
    Carp::croak("Cannot load package '$class' for header '$name': $@") unless eval { Module::Runtime::require_module($class) };
    Carp::croak("Class '$class' does not have method 'from_mime_string'") unless $class->can('from_mime_string');
  }

  my @values = $self->header_raw($name, $index);
  if (wantarray) {
    return map { $class->from_mime_string($_) } @values;
  } else {
    return $class->from_mime_string(@values);
  }
}

sub _maybe_decode {
  my ($name, $str_ref) = @_;
  $$str_ref = Email::MIME::Encode::maybe_mime_decode_header($name, $$str_ref);
  return;
}

sub get_class_for_header {
  my ($self, $name) = @_;
  return $header_to_class_map{lc $name};
}

sub set_class_for_header {
  my ($self, $class, $header) = @_;
  $header = lc $header;
  Carp::croak("Class for header '$header' is already set") if defined $header_to_class_map{$header};
  $header_to_class_map{$header} = $class;
  return;
}

1;

__END__

=pod

=encoding UTF-8

=head1 NAME

Email::MIME::Header - the header of a MIME message

=head1 VERSION

version 1.954

=head1 DESCRIPTION

This object behaves like a standard Email::Simple header, with the following
changes:

=over 4

=item *

the C<header> method automatically decodes encoded headers if possible

=item *

the C<header_as_obj> method returns an object representation of the header value

=item *

the C<header_raw> method returns the raw header; (read only for now)

=item *

stringification uses C<header_raw> rather than C<header>

=back

Note that C<header_set> does not do encoding for you, and expects an
encoded header.  Thus, C<header_set> round-trips with C<header_raw>,
not C<header>!  Be sure to properly encode your headers with
C<Encode::encode('MIME-Header', $value)> before passing them to
C<header_set>.  And be sure to use minimal version 2.83 of Encode
module due to L<bugs in MIME-Header|Encode::MIME::Header/BUGS>.

Alternately, if you have Unicode (character) strings to set in headers, use the
C<header_str_set> method.

=head1 PERL VERSION

This library should run on perls released even a long time ago.  It should
work on any version of perl released in the last five years.

Although it may work on older versions of perl, no guarantee is made that the
minimum required version will not be increased.  The version may be increased
for any reason, and there is no promise that patches will be accepted to
lower the minimum required perl.

=head1 AUTHORS

=over 4

=item *

Ricardo SIGNES <cpan@semiotic.systems>

=item *

Casey West <casey@geeknest.com>

=item *

Simon Cozens <simon@cpan.org>

=back

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2004 by Simon Cozens and Casey West.

This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.

=cut