=encoding utf8

=head1 NAME

Mail::Server::IMAP4::List - folder related IMAP4 answers

=head1 SYNOPSIS

  my $imap = Mail::Server::IMAP4::List->new(
    folders   => $folders,   # Mail::Box::Identity
    inbox     => $inbox,     # Mail::Box
    delimiter => '#'
  );

  my $imap = Mail::Server::IMAP4::List->new(user => $user);
  print $imap->list(...);        # for LIST command

=head1 DESCRIPTION

=head1 METHODS

=head2 Constructors

=over 4

=item $class-E<gt>B<new>(%options)

Create a (temporary) object to handle the LIST requests for
a certain user, based upon a set of folders.  The data is kept by
L<Mail::Box::Identity|Mail::Box::Identity> and L<Mail::Box::Collection|Mail::Box::Collection> objects, which
mean that the folders will not be opened to answer these questions.

 -Option   --Default
  delimiter  '/'
  folders    <from user>
  inbox      <from user>
  user       undef

=over 2

=item delimiter => STRING|CODE

Either the constant delimiter, or a code reference which will get passed
a folder name and should return the delimiter string used in that name.
If that folder name is empty, the default delimiter must be reported.
See L<delimiter()|Mail::Server::IMAP4::List/"Attributes"> for an example.

=item folders => OBJECT

You need to specify either a set of folders explicitly or via the
user. Some L<Mail::Box::Identity|Mail::Box::Identity> OBJECT is needed.

=item inbox => BOOLEAN

For now, only used to see whether there is an inbox, so a truth value will
do.  This may change in the future.  By default, the flag is set if
C<user> inbox is defined.

=item user => OBJECT

A L<Mail::Box::Manage::User|Mail::Box::Manage::User> OBJECT, representing the user who's folders
must get reported.

=back

=back

=head2 Attributes

=over 4

=item $obj-E<gt>B<delimiter>( [$foldername] )

Returns the delimiter string.  The foldername is only required when a
CODE reference was specified at initiation.

» example: setting-up an IMAP4 delimiter

  sub delim($)
  {   my $path = shift;
      my ($delim, $root)
        = $path =~ m/^(#news\.)/ ? ('.', $1)
        : $path =~ m!^/!         ? ('/', '/')
        :                          ('/', '');

      wantarray ? ($delim, $root) : $delim;
  }

  my $list = Mail::Server::IMAP4::List->new(delimiter => \&delim, ...);
  print $list->delimiter('abc/xyz');      # returns a / (slash) and ''
  print $list->delimiter('#news.feed');   # returns a . (dot)   and $news.
  print $list->delimiter('');             # returns default delimiter

=item $obj-E<gt>B<folders>()

Returns the L<Mail::Box::Identity|Mail::Box::Identity> of the toplevel folder.

=item $obj-E<gt>B<inbox>()

Returns the L<Mail::Box|Mail::Box> or filename of the INBOX.

=item $obj-E<gt>B<user>()

Returns the L<Mail::Box::Manage::User|Mail::Box::Manage::User> object, if defined.

=back

=head2 IMAP Commands

=over 4

=item $obj-E<gt>B<list>($base, $pattern)

IMAP's LIST command.  The request must be partially decoded, the answer
will need to be encoded.

» example: using IMAP list

  my $imap  = Mail::Server::IMAP4::List->new(delimiter => \&delim, ...);
  local $"  = ';';

  my @lines = $imap->list('', '');  # returns the default delimiter
  print ">@{$lines[0]}<";           #  >(\Noselect);/;<

  my @lines = $imap->list('#news',''); # specific delimiter
  print ">@{$lines[0]}<";           #  >(\Noselect);.;<

  my @lines = $imap->list('top/x/', '%');
  print ">@$_<," foreach @lines;    #  >();/;/tmp/x/y<,>(\Marked);/;/tmp/x/z<

=back

=head1 DETAILS

See

=over 4

=item RFC2060: "Internet Message Access Protocol IMAP4v1"

sections 6.3.8 (LIST question) and 7.2.2 (LIST answer)

=back

=head1 SEE ALSO

This module is part of Mail-Box-IMAP4 version 4.000,
built on December 10, 2025. Website: F<http://perl.overmeer.net/CPAN/>

=head1 LICENSE

For contributors see file ChangeLog.

This software is copyright (c) 2001-2025 by Mark Overmeer.

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

