###########################################################################
#
# SectionList.pm --
# A component of the Greenstone digital library software
# from the New Zealand Digital Library Project at the 
# University of Waikato, New Zealand.
#
# Copyright (C) 1999 New Zealand Digital Library Project
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
###########################################################################

# Same as List classifier but includes all sections of document
# (excluding top level) rather than just top level document 
# itself

# 12/05/02 Added usage datastructure - John Thompson

package SectionList;

use List;
use sorttools;

sub BEGIN {
    @ISA = ('List');
}

my $options = { 'name'     => "SectionList",
		'desc'     => "{SectionList.desc}",
		'inherits' => "Yes" };

#  sub print_usage {
#      print STDERR "
#    usage: classify SectionList [options]
#    options:

#     -metadata X    Metadata field used for classification,
#                    list will be sorted by this element.

#     -buttonname X  (optional) Title field for this classification.
#                    if not included title field will be Metaname. 

#     -sort X        (optional) Sort documents in list by this metadata field.
#                    By default it will sort by Metaname, or (if this is not
#                    set) in build (random) order.

#  Same as List classifier but includes all sections of document
#  (excluding top level) rather than just top level document.
#  ";
#  }

sub new {
    my $class = shift (@_);
    my $self = new List($class, @_);

    # 14-05-02 To allow for proper inheritance of arguments - John Thompson
    my $option_list = $self->{'option_list'};
    push( @{$option_list}, $options );

    return bless $self, $class;
}

sub classify {
    my $self = shift (@_);
    my ($doc_obj, @options) = @_;
    
    my $thissection = undef;

    my $option;
    foreach $option (@options)
    {
	if ($option =~ m/^section=(\d+)$/i) 
	{
	    $thissection = $1;
	}
    }

    my $sortmeta = "";
    if (defined $self->{'sortname'}) {
	if ($self->{'sortname'} =~ /^filename$/i) {
	    $sortmeta = $doc_obj->get_source_filename();
	} else {
	    $sortmeta = $doc_obj->get_metadata_element($doc_obj->get_top_section(),
						       $self->{'sortname'});
	    if ($self->{'sortname'} eq "Creator") {
		&sorttools::format_string_name_english (\$sortmeta);
	    } else {
		&sorttools::format_string_english (\$sortmeta);
	    }
	}
	$sortmeta = "" unless defined $sortmeta;
    }

    if (!defined $thissection)
    {
	$thissection = $doc_obj->get_next_section ($doc_obj->get_top_section());
	while (defined $thissection) {
	    $self->classify_section($thissection, $doc_obj, $sortmeta);
	    $thissection = $doc_obj->get_next_section ($thissection);
	}
    }
    else
    {
	$self->classify_section($thissection, $doc_obj, $sortmeta);
    }
}

sub classify_section {
    my $self = shift (@_);
    my ($section, $doc_obj, $sortmeta) = @_;

    my $doc_OID = $doc_obj->get_OID();
    $sortmeta = "" unless defined $sortmeta;

    if (defined $self->{'sortname'}) {
	if (defined $self->{'metaname'}) {

	    my $metavalue = $doc_obj->get_metadata_element ($section, $self->{'metaname'});
	    if (defined $metavalue) {
		if (defined $self->{'list'}->{"$doc_OID.$section"}) {
		    my $outhandle = $self->{'outhandle'};
		    print $outhandle "WARNING: SectionList::classify called multiple times for $doc_OID.$section\n";
		} 
		$self->{'list'}->{"$doc_OID.$section"} = $sortmeta;
	    }
	} else {
	    if (defined $self->{'list'}->{"$doc_OID.$section"}) {
		my $outhandle = $self->{'outhandle'};
		print $outhandle "WARNING: SectionList::classify called multiple times for $doc_OID.$section\n";
	    } 
	    $self->{'list'}->{"$doc_OID.$section"} = $sortmeta;
	}

    } else {
	if (defined $self->{'metaname'}) {

	    my $metavalue = $doc_obj->get_metadata_element ($section, $self->{'metaname'});
	    if (defined $metavalue) {
		push (@{$self->{'list'}}, "$doc_OID.$section");
	    }
	} else {
	    push (@{$self->{'list'}}, "$doc_OID.$section");
	}
    }
}

1;