package SQL::Translator::Parser::DBI::Oracle;

=head1 NAME

SQL::Translator::Parser::DBI::Oracle - parser for DBD::Oracle

=head1 SYNOPSIS

See SQL::Translator::Parser::DBI.

=head1 DESCRIPTION

Uses DBI introspection methods to determine schema details.

=cut

use strict;
use warnings;
use DBI;
use SQL::Translator::Schema::Constants;
use SQL::Translator::Schema::Table;
use SQL::Translator::Schema::Field;
use SQL::Translator::Schema::Constraint;

our $VERSION = '1.66';

sub parse {
  my ($tr, $dbh) = @_;

  my $schema = $tr->schema;

  my $db_user = uc $tr->parser_args()->{db_user};
  my $sth     = $dbh->table_info(undef, $db_user, '%', 'TABLE');

  while (my $table_info = $sth->fetchrow_hashref('NAME_uc')) {
    next if ($table_info->{TABLE_NAME} =~ /\$/);

    # create the table

    my $table = $schema->add_table(
      name => $table_info->{TABLE_NAME},
      type => $table_info->{TABLE_TYPE},
    );

    # add the fields (columns) for this table

    my $sth;

    $sth = $dbh->column_info(undef, $table_info->{TABLE_SCHEM}, $table_info->{TABLE_NAME}, '%');

    while (my $column = $sth->fetchrow_hashref('NAME_uc')) {
      my $f = $table->add_field(
        name          => $column->{COLUMN_NAME},
        default_value => $column->{COLUMN_DEF},
        data_type     => $column->{TYPE_NAME},
        order         => $column->{ORDINAL_POSITION},
        size          => $column->{COLUMN_SIZE},
      ) || die $table->error;

      $f->is_nullable($column->{NULLABLE} == 1);
    }

    # add the primary key info

    $sth = $dbh->primary_key_info(undef, $table_info->{TABLE_SCHEM}, $table_info->{TABLE_NAME},);

    while (my $primary_key = $sth->fetchrow_hashref('NAME_uc')) {
      my $f = $table->get_field($primary_key->{COLUMN_NAME});
      $f->is_primary_key(1);
    }

    # add the foreign key info (constraints)

    $sth = $dbh->foreign_key_info(undef, undef, undef, undef, $table_info->{TABLE_SCHEM}, $table_info->{TABLE_NAME},);

    my $cons = {};
    while (my $foreign_key = $sth->fetchrow_hashref('NAME_uc')) {
      my $name = $foreign_key->{FK_NAME};
      $cons->{$name}->{reference_table} = $foreign_key->{UK_TABLE_NAME};
      push @{ $cons->{$name}->{fields} },           $foreign_key->{FK_COLUMN_NAME};
      push @{ $cons->{$name}->{reference_fields} }, $foreign_key->{UK_COLUMN_NAME};
    }

    for my $name (keys %$cons) {
      my $c = $table->add_constraint(
        type             => FOREIGN_KEY,
        name             => $name,
        fields           => $cons->{$name}->{fields},
        reference_fields => $cons->{$name}->{reference_fields},
        reference_table  => $cons->{$name}->{reference_table},
      ) || die $table->error;
    }
  }

  return 1;
}

1;

=pod

=head1 AUTHOR

Earl Cahill E<lt>cpan@spack.netE<gt>.

=head1 ACKNOWLEDGEMENT

Initial revision of this module came almost entirely from work done by
Todd Hepler E<lt>thepler@freeshell.orgE<gt>.  My changes were
quite minor (ensuring NAME_uc, changing a couple variable names,
skipping tables with a $ in them).

Todd claimed his work to be an almost verbatim copy of
SQL::Translator::Parser::DBI::PostgreSQL revision 1.7

For me, the real work happens in DBD::Oracle and DBI, which, also
for me, that is the beauty of having introspection methods in DBI.

=head1 SEE ALSO

SQL::Translator, DBD::Oracle.

=cut