package Koha::Util::MARC;

# Copyright 2013 C & P Bibliography Services
#
# This file is part of Koha.
#
# Koha 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 3 of the License, or (at your option) any later
# version.
#
# Koha 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 Koha; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

use Modern::Perl;
use MARC::Record;

=head1 NAME

Koha::Util::MARC - utility class with routines for working with MARC records

=head1 METHODS

=head2 createMergeHash

Create a hash to use when merging MARC records

=cut

sub createMergeHash {
    my ( $record, $tagslib ) = @_;

    return unless $record;

    my @array;
    my @fields = $record->fields();

    foreach my $field (@fields) {
        my $fieldtag = $field->tag();
        if ( $fieldtag < 10 ) {
            if (
                !defined($tagslib)
                || ( defined( $tagslib->{$fieldtag} )
                    && $tagslib->{$fieldtag}->{'@'}->{'tab'} >= 0 )
              )
            {
                push @array, {
                    tag   => $fieldtag,
                    key   => _createKey(),
                    value => $field->data(),
                };
            }
        }
        else {
            my @subfields = $field->subfields();
            my @subfield_array;
            foreach my $subfield (@subfields) {
                if (
                    !defined($tagslib)
                    || (   defined $tagslib->{$fieldtag}
                        && defined $tagslib->{$fieldtag}->{ @$subfield[0] }
                        && defined $tagslib->{$fieldtag}->{ @$subfield[0] }->{'tab'}
                        && $tagslib->{$fieldtag}->{ @$subfield[0] }->{'tab'} >= 0 )
                  )
                {
                    push @subfield_array, {
                        subtag => @$subfield[0],
                        subkey => _createKey(),
                        value  => @$subfield[1],
                    };
                }

            }

            if (
                (
                    !defined($tagslib) || ( defined $tagslib->{$fieldtag}
                        && defined $tagslib->{$fieldtag}->{'tab'}
                        && $tagslib->{$fieldtag}->{'tab'} >= 0 )
                )
                && @subfield_array
              )
            {
                push @array, {
                      tag        => $fieldtag,
                      key        => _createKey(),
                      indicator1 => $field->indicator(1),
                      indicator2 => $field->indicator(2),
                      subfield   => [@subfield_array],
                  };
            }

        }
    }
    return [@array];
}

=head2 _createKey

Create a random value to set it into the input name

=cut

sub _createKey {
    return int(rand(1000000));
}

=head2 getAuthorityAuthorizedHeading

Retrieve the authorized heading from a MARC authority record

=cut

sub getAuthorityAuthorizedHeading {
    my ( $record, $schema ) = @_;
    return unless ( ref $record eq 'MARC::Record' );
    if ( $schema eq 'unimarc' ) {

        # construct UNIMARC summary, that is quite different from MARC21 one
        # accepted form
        foreach my $field ( $record->field('2..') ) {
            return $field->as_string('abcdefghijlmnopqrstuvwxyz');
        }
    }
    else {
        foreach my $field ( $record->field('1..') ) {
            my $tag = $field->tag();
            next if "152" eq $tag;

            # FIXME - 152 is not a good tag to use
            # in MARC21 -- purely local tags really ought to be
            # 9XX
            if ( $tag eq '100' ) {
                return $field->as_string('abcdefghjklmnopqrstvxyz68');
            }
            elsif ( $tag eq '110' ) {
                return $field->as_string('abcdefghklmnoprstvxyz68');
            }
            elsif ( $tag eq '111' ) {
                return $field->as_string('acdefghklnpqstvxyz68');
            }
            elsif ( $tag eq '130' ) {
                return $field->as_string('adfghklmnoprstvxyz68');
            }
            elsif ( $tag eq '148' ) {
                return $field->as_string('abvxyz68');
            }
            elsif ( $tag eq '150' ) {
                return $field->as_string('abvxyz68');
            }
            elsif ( $tag eq '151' ) {
                return $field->as_string('avxyz68');
            }
            elsif ( $tag eq '155' ) {
                return $field->as_string('abvxyz68');
            }
            elsif ( $tag eq '180' ) {
                return $field->as_string('vxyz68');
            }
            elsif ( $tag eq '181' ) {
                return $field->as_string('vxyz68');
            }
            elsif ( $tag eq '182' ) {
                return $field->as_string('vxyz68');
            }
            elsif ( $tag eq '185' ) {
                return $field->as_string('vxyz68');
            }
            else {
                return $field->as_string();
            }
        }
    }
    return;
}

=head2 set_marc_field

    set_marc_field($record, $marcField, $value);

Set the value of $marcField to $value in $record. If the field exists, it will
be updated. If not, it will be created.

=head3 Parameters

=over 4

=item C<$record>

MARC::Record object

=item C<$marcField>

the MARC field to modify, a string in the form of 'XXX$y'

=item C<$value>

the value

=back

=cut

sub set_marc_field {
    my ($record, $marcField, $value) = @_;

    if ($marcField) {
        my ($fieldTag, $subfieldCode) = split /\$/, $marcField;
        if( !$subfieldCode ) {
            warn "set_marc_field: Invalid marcField format: $marcField\n";
            return;
        }
        my $field = $record->field($fieldTag);
        if ($field) {
            $field->update($subfieldCode => $value);
        } else {
            $field = MARC::Field->new($fieldTag, ' ', ' ',
                $subfieldCode => $value);
            $record->append_fields($field);
        }
    }
}

1;