source: trunk/gsdl/perllib/classify/AZSectionList.pm@ 6111

###########################################################################
#
# AZSectionList.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.
#
###########################################################################

# classifier plugin for sorting sections alphabetically

# this is very similar to AZList except it sorts by
# section level metadata (excluding the top level)
# instead of just top level metadata

# the only change is to the classify() subroutine which 
# must now iterate through each section, adding each
# to the classification

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

package AZSectionList;

use AZList;
use sorttools;

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

my $arguments = 
    [ { 'name' => "metadata",
    'desc' => "{List.metadata}",
    'type' => "metadata",
    'reqd' => "yes" },
      { 'name' => "buttonname",
    'desc' => "{AZList.buttonname}",
    'type' => "string",
    'deft' => "Metadata element specified with -metadata",
    'reqd' => "no" } ];

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

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

#    -metadata X    (required) 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. 

#    -removeprefix regex A prefix to ignore in the Metadata values
#                        for the field when sorting.
#  This is very similar to AZList except it sorts by section level metadata
#  (excluding the top level) instead of just top level metadata.
#  ";
#  }

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

    my $doc_OID = $doc_obj->get_OID();
    my $thissection = $doc_obj->get_next_section ($doc_obj->get_top_section());

    while (defined $thissection) {
    $self->classify_section ($thissection, $doc_obj);
    $thissection = $doc_obj->get_next_section ($thissection);
    }
}

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

    my $doc_OID = $doc_obj->get_OID();
    my $metavalue = $doc_obj->get_metadata_element ($section, $self->{'metaname'});

    # if this section doesn't contain the metadata element we're
    # sorting by we won't include it in this classification

    if (defined $metavalue && $metavalue ne "") {
    if ($self->{'removeprefix'}) {
        $metavalue =~ s/^$self->{'removeprefix'}//;
    }
    if ($self->{'metaname'} eq 'Creator') {
        &sorttools::format_string_name_english (\$metavalue);
    } else {
        &sorttools::format_string_english (\$metavalue);
    }
    if (defined $self->{'list'}->{"$doc_OID.$section"}) {
        my $outhandle = $self->{'outhandle'};
        print $outhandle "WARNING: AZSectionList::classify called multiple times " .
        "for $doc_OID.$section\n";
    } 
    $self->{'list'}->{"$doc_OID.$section"} = $metavalue;
    }
}


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