#!/usr/bin/perl
# -*- coding: iso-8859-15 -*-
###############################################################################
=pod

=item B<prepbibs> --file foo.mrc 

Converts a MARC binary file internally to XML and changes 999 subfields to 
998s with a special subfield z with a value of 'converted 999 field' added for 
identification.

=back
=cut

###############################################################################

use strict;
use warnings;

use Data::Dumper;
use Env qw(
    HOME PGHOST PGPORT PGUSER PGDATABASE MIGSCHEMA
    MIGBASEWORKDIR MIGBASEGITDIR MIGGITDIR MIGWORKDIR
);
use Pod::Usage;
use Switch;
use Getopt::Long;
use MARC::Batch;
use MARC::Record;
use MARC::Field;
use MARC::Batch;
use MARC::File::XML;
use Cwd 'abs_path';
use Cwd qw(getcwd);
use List::MoreUtils qw(uniq);
use FindBin;
my $mig_bin = "$FindBin::Bin/";
use lib "$FindBin::Bin/";
use KMig;
use open ':encoding(utf8)';

binmode STDOUT, ":utf8";

pod2usage(-verbose => 2) if defined $ARGV[0] && $ARGV[0] eq '--help';
pod2usage(-verbose => 1) if ! $ARGV[1];

my $infile;
my $i = 0;

my $ret = GetOptions(
    'file:s'           		 => \$infile
);

my $outfile = $infile . '.prepped_xml';
my $errorfile = $infile . '.errors_xml';

open my $outfh, '>:utf8', $outfile or die "Can't open output file $!\n";
open my $errorfh, '>:utf8', $errorfile or die "Can't open error file $!\n";

my $filetype = `file $infile`;
my $batch;
if ($filetype =~ m/MARC21/) {
	$batch = MARC::Batch->new( 'USMARC', $infile );
} else {
	$batch = MARC::Batch->new( 'XML', $infile );
}
$batch->strict_off();

while ( eval {$record = $batch->next()} or do { if ($@) { print $errorfh $record->as_xml(); next; } } ) {
 	$i++;
 	print "Processed: $i\n" if ($i % 100) == 0;
	my @nnn = $record->field('999');
	foreach my $n (@nnn) {
		$n->set_tag('998');
		$n->add_subfields( 'z' => 'converted 999 field' );
	}
    print $outfh $record->as_xml(),"\n";
}

close ($infile);
close ($outfile);
close ($errorfile);

########### functions

sub abort {
    my $msg = shift;
    print STDERR "$0: $msg", "\n";
    exit 1;
}