#!/usr/bin/perl

###############################################################################
=pod

=item B<loadbibs> --stage_file foo.mrc 

Takes a load of bibs from a binary marc file and loads them into mig staging table 
of bibio_record_entry.

Takes these optional arguments:

--append 

When used it does not drop the staging table and instead adds onto it.  

--source

Sets an x_source value on the staging table to the one supplied instead of the 
default of none.

--xml 

By default the program assumes a USMARC file.  This flag will identify it as 
a MARCXML file instead.

=back

=cut

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

use strict;
use warnings;

use DBI;
#binmode STDIN, ':bytes';
use Env qw(
    HOME PGHOST PGPORT PGUSER PGDATABASE MIGSCHEMA
    MIGBASEWORKDIR MIGBASEGITDIR MIGGITDIR MIGWORKDIR
);
use Pod::Usage;
use Switch;
use Cwd 'abs_path';
use FindBin;
use UNIVERSAL;
my $mig_bin = "$FindBin::Bin/";
use lib "$FindBin::Bin/";
use Mig;

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

my $next_arg_is_file = 0;
my $append = 0;
my $next_arg_is_source = 0;
my $next_arg_is_stage = 0;
my $stage_table = 'biblio_record_entry';
my $source = 'default';
my $file_is_xml = 0;
my $dbh = Mig::db_connect();
my $infile;
my $i = 0;
my $batch;
binmode STDIN, ':utf8';

#MARC::Charset->assume_unicode(1); 
MARC::Charset->ignore_errors(1);

foreach my $arg (@ARGV) {
    if ($arg eq '--stage_file') {
        $next_arg_is_file = 1;
        next;
    }
    if ($next_arg_is_file) {
        $infile = $arg;
        $next_arg_is_file = 0;
        next;
    }
    if ($arg eq '--source') {
        $next_arg_is_source = 1;
        next;
    }
    if ($next_arg_is_source) {
        $source = $arg;
        $next_arg_is_source = 0;
        next;
    }
}

my $bre_test = check_for_table($dbh,'biblio_record_entry');
if ($bre_test == 0) { create_child_bre($dbh); }

my $xmig_test = check_for_column($dbh,'biblio_record_entry','x_migrate');
if ($xmig_test == 0) { add_column($dbh,'biblio_record_entry','x_migrate','BOOLEAN DEFAULT TRUE');

my $xsource_test = check_for_column($dbh,'biblio_record_entry','x_source');
if ($xsource_test == 0) { add_column($dbh,'biblio_record_entry','x_source','TEXT');

my $last_xact;
if ($source) { $last_xact = "'$MIGSCHEMA $source'" } else { $last_xact = "'$MIGSCHEMA'"; }

#flatten out MARC XML FILE
open my $xml, "<:encoding(utf8)", $infile or abort('could not open MARC XML file');
$i = 0;
my $record;
while(my $line = <$xml>) {
	 if ($line =~ /^<\/?collection/) { next; }
	 chomp $line;
	 $record = $record . $line;
	 if ($line =~ /^<\/record/) {
		stage_record($dbh,$record,$last_xact); 
		$record = '';
	}

close $xml;


#load the MARC XML FILE TO STAGING 
report_progress("Records staged", $i) if 0 != $i % 100;

print "Finis.\n";

# beyond here be functions 

sub create_child_bre {
    my $dbh = shift;
    $dbh->do("DO \$\$ 
        DECLARE
            t   BOOLEAN;
        BEGIN
        SELECT EXISTS(SELECT 1 FROM information_schema.tables WHERE table_schema = '$MIGSCHEMA' AND table_name = 'biblio_record_entry') INTO t;
        IF t = FALSE THEN
            PERFORM migration_tools.build_specific_base_staging_table ('$MIGSCHEMA','biblio.record_entry');
        END IF;
        END \$\$;");

    return ();
}

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

sub report_progress {
    my ($msg, $counter) = @_;
    if (defined $counter) {
        print STDERR "$msg: $counter\n";
    } else {
        print STDERR "$msg\n";
    }
}

sub stage_record {
    my $dbh = shift;
    my $record = shift;
	my $last_xact = shift;
	$record = '$_$' . $record . '$_$';
    my $sql = "INSERT INTO $MIGSCHEMA.biblio_record_entry (last_xact_id,marc) VALUES ($last_xact,$record);";
    my $sth = $dbh->prepare($sql);
    $sth->execute();
	return;
}

sub check_for_table {
    my $dbh = shift;
    my $table = shift;
    my $sql = "SELECT 1 FROM information_schema.tables WHERE table_schema = '$MIGSCHEMA' AND table_name = '$table';";
    my $sth = $dbh->prepare($sql);
    $sth->execute();
    my @sqlresult = $sth->fetchrow_array;
    my $r = pop @sqlresult;
    if ($r) { return $r; } else { return 0; }
}

sub check_for_column {
    my $dbh = shift;
    my $table = shift;
	my $column = shift;
    my $sql = "SELECT 1 FROM information_schema.columns WHERE table_schema = '$MIGSCHEMA' AND table_name = '$table' AND column_name = $column;";
    my $sth = $dbh->prepare($sql);
    $sth->execute();
    my @sqlresult = $sth->fetchrow_array;
    my $r = pop @sqlresult;
    if ($r) { return $r; } else { return 0; }
}

sub add_column {
    my $dbh = shift;
    my $table = shift;
    my $column = shift;
	my $column_type = shift;
    my $sql = "ALTER TABLE $MIGSCHEMA.$table ADD COLUMN $COLUMN $COLUMN_TYPE;";
	my $r = check_for_column($dbh,$table,$column);
	if ($r == 0) { abort('failed to create column'; } else { return $r; }
}