File Coverage

blib/lib/Text/BibTeX/BibFormat.pm

Criterion	Covered	Total	%
statement	90	117	76.9
branch	26	60	43.3
condition	7	12	58.3
subroutine	21	24	87.5
pod	1	17	5.8
total	145	230	63.0

# ----------------------------------------------------------------------
# NAME       : BibFormat.pm
# CLASSES    : Text::BibTeX::BibFormat
# RELATIONS  : sub-class of Text::BibTeX::StructuredEntry
#              super-class of Text::BibTeX::BibEntry
# DESCRIPTION: Provides methods for final output formatting of
#              bibliographic entries.
# CREATED    : 1997/11/24, GPW
# MODIFIED   :
# VERSION    : $Id$
# COPYRIGHT  : Copyright (c) 1997 by Gregory P. Ward.  All rights reserved.
#
#              This file is part of the Text::BibTeX library.  This is free
#              software; you can redistribute it and/or modify it under the
#              same terms as Perl itself.
# ----------------------------------------------------------------------

package Text::BibTeX::BibFormat;

use Carp;
use strict;
use vars qw(@ISA $VERSION);

use Text::BibTeX::Name;
use Text::BibTeX::NameFormat;
use Text::BibTeX::Structure;

@ISA = qw(Text::BibTeX::StructuredEntry);
$VERSION = 0.87;

use Text::BibTeX qw(:subs display_list :nameparts :joinmethods);

=head1 NAME

Text::BibTeX::BibFormat - formats bibliography entries

=head1 SYNOPSIS

   # Assuming $entry comes from a database of the 'Bib' structure
   # (i.e., that it's blessed into the BibEntry class, which inherits
   # the format method from BibFormat):
   @blocks = $entry->format;

=head1 DESCRIPTION

The C class is a base class of
C for formatting bibliography entries.  It thus
performs the main job of any program that would hope to supplant BibTeX
itself; the other important job (sorting) is handled by its companion
class, C.

C (the C prefix will be dropped for brevity)
pays attention to almost all of the structure options described in
L; it only ignores those that cover sorting,
currently just C.  In particular, all of the "markup" options
control what language is generated by C; if none of those
options are set, then it will generate plain, unmarked text.

The only method in C's documented interface (so far) is
C.  (The class defines many other methods, but these should not
be necessary to outsiders, so they are undocumented and subject to
change.)

=head1 METHODS

=over 4

=cut

# ----------------------------------------------------------------------
# Ordinary subroutines:

sub connect_words
{
   my ($s1, $s2) = @_;

   return $s1 . ((length ($s2) < 3) ? '~' : ' ') . $s2;
}


# ----------------------------------------------------------------------
# Utility methods (eg. apply a bit of markup to a string or field)

sub markup_field
{
   my ($self, $markup, $field) = @_;

   $markup = $self->structure->get_options ("${markup}_mkup")
      unless (ref $markup eq 'ARRAY' && @$markup == 2);
   croak "${markup}_mkup option not defined"
      unless defined $markup;

   $self->exists ($field)
      ? $markup->[0] . $self->get ($field) . $markup->[1]
      : '';
}


sub markup_string
{
   my ($self, $markup, $string) = @_;

   $markup = $self->structure->get_options ("${markup}_mkup")
      unless (ref $markup eq 'ARRAY' && @$markup == 2);
   croak "${markup}_mkup option not defined"
      unless defined $markup;

   $markup->[0] . $string . $markup->[1];
}


# ----------------------------------------------------------------------
# Formatting methods I: utility methods called by the entry-formatters

sub format_authors
{
   my $self = shift;

   return '' unless $self->exists ('author');
   my @authors = $self->names ('author');
   $self->format_names (\@authors)
}


sub format_editors
{
   my $self = shift;

   # The word used to indicate editorship should be customizable --
   # might want it in another language, or abbreviated, or both.
   return '' unless $self->exists ('editor');
   my @editors = $self->names ('editor');
   my $tackon = (@editors == 1) ? ', editor' : ', editors';
   $self->format_names (\@editors) . $tackon;
}


sub format_names
{
   my ($self, $names) = @_;
   my ($format, $name);

   my ($order, $style) =
      $self->structure->get_options ('nameorder', 'namestyle');
   croak "format_names: bad nameorder option \"$order\""
      unless $order eq 'first' || $order eq 'last';
   croak "format_names: bad namestyle option \"$style\""
      unless $style =~ /^(full|abbrev|nopunct|nospace)$/;

   $order = ($order eq 'first') ? 'fvlj' : 'vljf';
   $format = Text::BibTeX::NameFormat->new ($order, ! ($style eq 'full'));

   $format->set_text (&BTN_FIRST, undef, undef, undef, '')
      if $style eq 'nopunct' || $style eq 'nospace';
   $format->set_options (&BTN_FIRST, 1, &BTJ_NOTHING, &BTJ_SPACE)
      if $style eq 'nospace';

   foreach $name (@$names)
   {
      $name = $name->format ($format);
      $name = 'et. al.' if $name eq 'others';
   }

   return $self->markup_string ('name', display_list($names,0));
}


sub format_atitle
{
   my $self = shift;

   my $lower = $self->structure->get_options ('atitle_lower');
   my $title = $self->get ('title');
   $title = change_case ('t', $title) if $lower;
   $self->markup_string ('atitle', $title);
#   $markup->[0] . $title . $markup->[1];
}


sub format_btitle
{
   my $self = shift;

   $self->markup_field ('btitle', 'title');
#   my $markup = $self->structure->get_options ('btitle_mkup');
#   my $title = $self->get ('title');
#   $markup->[0] . $title . $markup->[1];
}


# sub format_xref_article
# {
#    my $self = shift;

#    # N.B. this assumes that the appropriate fields from the cross-
#    # referenced entry have already been put into the current entry!

#    # XXX hard-coded LaTeX markup here!!!

#    my ($key, $journal, $crossref);
#    $key = $self->get ('key');
#    $journal = $self->get ('journal');
#    $crossref = $self->get ('crossref');
#    if (defined $key)
#    {
#       return "In $key \cite{$crossref}";
#    }
#    else
#    {
#       if (defined $journal)
#       {
#          return "In {\em $journal} \cite{$crossref}";
#       }
#       else
#       {
#          $self->warn ("need key or journal for crossref");
#          return " \cite{$crossref}";
#       }
#    }
# }


sub format_pages
{
   my $self = shift;

   my $pages = $self->get ('pages');
   if ($pages =~ /[,+-]/)               # multiple pages?
   {
      $pages =~ s/([^-])-([^-])/$1--$2/g;
      return connect_words ("pages", $pages);
   }
   else
   {
      return connect_words ("page", $pages);
   }
}


sub format_vol_num_pages
{
   my $self = shift;

   my ($vol, $num, $pages) = $self->get ('volume', 'number', 'pages');
   my $vnp = '';
   $vnp .= $vol if defined $vol;
   $vnp .= "($num)" if defined $num;
   $vnp .= ":$pages" if defined $pages;
   return $vnp;
}


sub format_bvolume
{
   my $self = shift;
   my $volser;                          # potentially volume and series

   if ($self->exists ('volume'))
   {
      $volser = connect_words ('volume', $self->get ('volume'));
      $volser .= ' of ' . $self->markup_field ('btitle', 'series')
         if $self->exists ('series');
      return $volser;
   }
   else
   {
      return '';
   }
}


sub format_number_series
{
   my ($self, $mid_sentence) = @_;

   if ($self->exists ('volume'))
   {
      # if 'volume' field exists, then format_bvolume took care of
      # formatting it, so don't do anything here
      return '';
   }
   else
   {
      if ($self->exists ('number'))
      {
         my $numser;

         $numser = connect_words ($mid_sentence ? 'number' : 'Number',
                                  $self->get ('number'));
         if ($self->exists ('series'))
         {
            $numser .= ' in ' . $self->get ('series');
         }
         else
         {
            $self->warn ("there's a number but no series " .
                         "(is this warning redundant?!?)");
         }
         return $numser;
      }
      else
      {
         # No 'number' -- just return the 'series' (or undef if none)
         return $self->get ('series');
      }
   }  # no 'volume' field
}  # format_number_series


sub format_edition
{
   my ($self, $mid_sentence) = @_;

   # XXX more fodder for I18N here: the word 'edition'
   return '' unless $self->exists ('edition');
   my $case_transform = $mid_sentence ? 'l' : 't';
   return change_case ($case_transform, $self->get ('edition')) . ' edition';

}  # format_edition


sub format_date
{
   my $self = shift;

   my @date = grep ($_, $self->get ('month', 'year'));
   return join (' ', @date);
}


# ----------------------------------------------------------------------
# The actual entry-formatting methods:
#   format_article
#   format_book
#   format_inbook
#   ...and so on.

# Each of these returns a list of blocks.
# A block is a list of sentences.
# A sentence is either a string or a list of clauses.
# Any clause, sentence, or block in any list may be empty or undefined;
#   it should be removed before output.
# If a sentence consists of a list of clauses, they should be joined
#   together with ", " to form the sentence-as-string.
#
# For example, the formatted entry for an article (in the absence of
# cross-references) consists of four blocks:
#   - the name block, which has a single sentence; this sentence
#     has a single clause (the list of author names), and thus is
#     represented as a string like "Joe Blow, Fred Jones, and John Smith"
#   - the title block, which has a single sentence; this sentence
#     has a single clause, the title of the article, eg. "The mating
#     habits of foobars"
#   - the journal block, which consists of a single sentence that has
#     three clauses: the journal name, the volume/number/pages, and
#     the date.  When the three clauses are joined, we get something like
#     "Journal of Foo, 4(5):122--130, May 1996" for the single sentence
#     in the block.
#   - the note block -- if the entry has no `note' field, this block
#     will be an undefined value rather than a list of sentences
#
# These four blocks are returned from `format_article' (and thus from
# `format') as a list-of-lists-of-(strings or lists-of-strings.  That
# is, each format methods returns a list of blocks, each of which is in
# turn a list of sentences.  (Hence "list of lists of X".)  Each
# sentence is either a string ("list of lists of strings") or a list of
# clauses ("list of lists of lists of strings').  Clear?  Hope so!
#
#   [                                           # enter list of blocks
#    ["Joe Blow, Fred Jones, and John Smith"]   # name block:
#                                               # 1 sentence w/ 1 clause
#    ["The mating habits of foobars"]           # title block:
#                                               # 1 sentence w/ 1 clause
#    [["Journal of Foo",                        # journal block:
#      "4(5):122--130",                         # 1 sentence w/ 3 clauses
#      "May 1996"]]
#    undef
#   ]
#
# A note: the journal name will normally have a bit of markup around it,
# say to italicize it -- that's determined by the calling application,
# though; the default markups are all empty strings.  There could
# probably be arbitrary markup for every element of an entry, but I
# haven't gone that far yet.
#
# It is then the responsibility of the calling application to apply the
# appropriate punctuation and munge all those lists of strings together
# into something worth printing.  The canonical application for doing
# this is btformat, which supports LaTeX 2.09, LaTeX2e, and HTML markup
# and output.


sub format_article
{
   my $self = shift;


   my $name_block = [$self->format_authors];
   my $title_block = [$self->format_atitle];
   my $journal_block = [[$self->markup_string('journal', $self->get ('journal')),
                         $self->format_vol_num_pages,
                         $self->format_date]];

#    if ($self->exists ('crossref'))
#    {
#       push (@blocks, [[$self->format_xref_article,
#                       $self->format_pages]]);
#    }
#    else
#    {
#    }

#    push (@blocks, [$self->get ('note')]) if $self->exists ('note');
#    @blocks;

   ($name_block, $title_block, $journal_block, $self->get ('note'));
}  # format_article


sub format_book
{
   my $self = shift;

   my $name_block =                     # author(s) or editor(s)
      ($self->exists ('author'))
         ? [$self->format_authors]
         : [$self->format_editors];
   my $title_block =                    # title (and volume)
      [[$self->format_btitle, $self->format_bvolume]];
   my $from_block =                     # number/series; publisher, address,
      [$self->format_number_series (0), # edition, date
       [$self->get ('publisher'), $self->get ('address'),
        $self->format_edition (0), $self->format_date]];

   ($name_block, $title_block, $from_block, $self->get('note'));

}  # format_book


# ----------------------------------------------------------------------
# Finally, the `format' method -- just calls one of the
# type-specific format methods (format_article, etc.)

=item format ()

Formats a single entry for inclusion in the bibliography of some
document.  The exact processing performed is highly dependent on the
entry type and the fields present; in general, you should be able to
join C's outputs together to create a single paragraph for
inclusion in a document of whatever markup language you're working with.

Returns a list of "blocks," which can either be jammed together like
sentences (for a traditional "tight" bibliography) or printed on
separate lines (for an "open" bibliography format).  Each block is a
reference to a list of sentences; sentences should be joined together
with an intervening period.  Each sentence is either a single string or
a list of clauses; clauses should be joined together with an intervening
comma.  Each clause is just a simple string.

See the source code for C for an example of how to use the
output of C.

=cut

sub format
{
   my $self = shift;

   my $type = $self->type;
   my $key = $self->key;
   my $method_name = 'format_' . $type;
   my $method = $self->can ($method_name);
   unless ($method)
   {
      $self->warn ("can't format entry: " .
                   "no method $method_name (for type $type)");
      return;
   }

   return &$method ($self);
}

1;

=back

=head1 SEE ALSO

L, L,
L

=head1 AUTHOR

Greg Ward

=head1 COPYRIGHT

Copyright (c) 1997-2000 by Gregory P. Ward.  All rights reserved.  This file
is part of the Text::BibTeX library.  This library is free software; you
may redistribute it and/or modify it under the same terms as Perl itself.