#!/usr/bin/perl

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

=item B<stagebibs> --file foo.xml

Takes a load of bibs from a UTF-8 MARC XML  file and loads them into mig staging 
table of bibio_record_entry.  This is done with no checking of file validity 
so records should be checked before hand and cleaned.

Takes one  optional arguments:

--source

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

=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 Data::Dumper;
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_legacy';
my $source = 'default';
my $file_is_xml = 0;
my $dbh = Mig::db_connect();
my $infile;
my $i = 0;
my $batch;
binmode STDIN, ':utf8';

foreach my $arg (@ARGV) {
    if ($arg eq '--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');
my $bre_legacy_test = check_for_table($dbh,'biblio_record_entry_legacy');
if ($bre_test == 0 and $bre_legacy_test == 0 ) { create_child_bre($dbh); rename_child_bre($dbh); }
if ($bre_test == 1 and $bre_legacy_test == 0 ) { rename_child_bre($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'); }

#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,$record,$source); 
		$record = '';
		$i++;
		if (($i % 100) == 0) { report_progress('Records stage', $i); }
	}
}
close $xml;

if ($i == 0) { print "No XML was processed, are you sure this is an XML file?\n"; }
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 rename_child_bre {
    my $dbh = shift;
    $dbh->do("DO \$\$ 
        BEGIN
        ALTER TABLE biblio_record_entry RENAME TO biblio_record_entry_legacy;
        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 $source = shift;
	my $last_xact = "'$MIGSCHEMA'";
	$record = '$_$' . $record . '$_$';
	my $sql;
	if ($source eq 'default') { $sql = "INSERT INTO $MIGSCHEMA.biblio_record_entry (last_xact_id,marc) VALUES ($last_xact,$record);"; }
		else { $sql = "INSERT INTO $MIGSCHEMA.biblio_record_entry (last_xact_id,marc,x_source) VALUES ($last_xact,$record,'$source');";  }
    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 $sth = $dbh->prepare($sql);
    $sth->execute();
    my @sqlresult = $sth->fetchrow_array;
	my $r = check_for_column($dbh,$table,$column);
	if ($r == 0) { abort('failed to create column'); } else { return $r; }
}