package SQL::Translator::Parser::DBI::SQLServer;

=head1 NAME

SQL::Translator::Parser::DBI::SQLServer - parser for SQL Server through DBD::ODBC

=head1 SYNOPSIS

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

=head1 DESCRIPTION

Uses DBI Catalog Methods.

=cut

use strict;
use warnings;
use DBI;
use SQL::Translator::Schema;
use Data::Dumper;

our ( $DEBUG, @EXPORT_OK );
our $VERSION = '1.61';
$DEBUG   = 0 unless defined $DEBUG;

no strict 'refs';

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

    if ($dbh->{FetchHashKeyName} ne 'NAME_uc') {
        warn "setting dbh attribute {FetchHashKeyName} to NAME_uc";
        $dbh->{FetchHashKeyName} = 'NAME_uc';
    }

    if ($dbh->{ChopBlanks} != 1) {
        warn "setting dbh attribute {ChopBlanks} to 1";
        $dbh->{ChopBlanks} = 1;
    }

    my $schema = $tr->schema;

    my ($sth, @tables, $columns);
    my $stuff;

    ### Columns

    # it is much quicker to slurp back everything all at once rather
    # than make repeated calls

    $sth = $dbh->column_info(undef, undef, undef, undef);


    foreach my $c (@{$sth->fetchall_arrayref({})}) {
        $columns
            ->{$c->{TABLE_CAT}}
                ->{$c->{TABLE_SCHEM}}
                    ->{$c->{TABLE_NAME}}
                        ->{columns}
                            ->{$c->{COLUMN_NAME}}= $c;
    }

    ### Tables and views

    # Get a list of the tables and views.
    $sth = $dbh->table_info();
    @tables   = @{$sth->fetchall_arrayref({})};

    my $h = $dbh->selectall_arrayref(q{
SELECT o.name, colid,c.text
  FROM syscomments c
  JOIN sysobjects o
    ON c.id = o.id
 WHERE o.type ='V'
ORDER BY o.name,
         c.colid
}
);

    # View text
    # I had always thought there was something 'hard' about
    # reconstructing text from syscomments ..
    # this seems to work fine and is certainly not complicated!

    foreach (@{$h}) {
        $stuff->{view}->{$_->[0]}->{text} .= $_->[2];
    }

    #### objects with indexes.
    map {
        $stuff->{indexes}->{$_->[0]}++
            if defined;
    } @{$dbh->selectall_arrayref("SELECT DISTINCT object_name(id)
                                    FROM sysindexes
                                   WHERE indid > 0 and indid < 255 and
                                         name not like '_WA_Sys%'")};

    ## slurp objects
    map {
        $stuff->{$_->[1]}->{$_->[0]} = $_;
    } @{$dbh->selectall_arrayref("SELECT name,type, id FROM sysobjects")};


    ### Procedures

    # This gets legitimate procedures by used the 'supported' API: sp_stored_procedures
    map {
        my $n = $_->{PROCEDURE_NAME};
        $n =~ s/;\d+$//;        # Ignore versions for now
        $_->{name} = $n;
        $stuff->{procedures}->{$n} = $_;
    } values %{$dbh->selectall_hashref("sp_stored_procedures", 'PROCEDURE_NAME')};


    # And this blasts in the text of 'legit' stored procedures.  Do
    # this rather than calling sp_helptext in a loop.

    $h = $dbh->selectall_arrayref(q{
SELECT o.name, colid,c.text
  FROM syscomments c
  JOIN sysobjects o
    ON c.id = o.id
 WHERE o.type in ('P', 'FN', 'TF', 'IF')
}
);

    foreach (@{$h}) {
        $stuff->{procedures}->{$_->[0]}->{text} .= $_->[2]
            if (defined($stuff->{procedures}->{$_->[0]}));
    }

    ### Defaults
    ### Rules
    ### Bind Defaults
    ### Bind Rules

    ### Triggers
    # Since the 'target' of the trigger is defined in the text, we will
    # just create them independently for now rather than associating them
    # with a table.

    $h = $dbh->selectall_arrayref(q{
SELECT o.name, colid,c.text
  FROM syscomments c
  JOIN sysobjects o
    ON c.id = o.id
  JOIN sysobjects o1
    ON (o.id = o1.instrig OR o.id = o1.deltrig or o.id = o1.updtrig)
 WHERE o.type ='TR'
ORDER BY o.name,
         c.colid
}
);
    foreach (@{$h}) {
        $stuff->{triggers}->{$_->[0]}->{text} .= $_->[2];
    }

    ### References
    ### Keys

    ### Types
    # Not sure what to do with these?
    $stuff->{type_info_all} = $dbh->type_info_all;

    ### Tables
    # According to the DBI docs, these can be

    # "TABLE"
    # "VIEW"
    # "SYSTEM TABLE"
    # "GLOBAL TEMPORARY",
    # "LOCAL TEMPORARY"
    # "ALIAS"
    # "SYNONYM"

    foreach my $table_info (@tables) {
        next
            unless (defined($table_info->{TABLE_TYPE}));

        if ($table_info->{TABLE_TYPE} eq "TABLE") {
            my $table = $schema->add_table(
                                           name =>
$table_info->{TABLE_NAME},
                                           type =>
$table_info->{TABLE_TYPE},
                                          ) || die $schema->error;

            # find the associated columns

            my $cols =
                $columns->{$table_info->{TABLE_CAT}}
                    ->{$table_info->{TABLE_SCHEM}}
                        ->{$table_info->{TABLE_NAME}}
                            ->{columns};

            foreach my $c (values %{$cols}) {
            my $is_auto_increment = $c->{TYPE_NAME} =~ s#(\(\))? identity##i;
                my $f = $table->add_field(
                                          name        => $c->{COLUMN_NAME},
                                          data_type   => $c->{TYPE_NAME},
                                          order       => $c->{ORDINAL_POSITION},
                                          size        => [$c->{COLUMN_SIZE},$c->{DECIMAL_DIGITS}],
                                         ) || die $table->error;
                $f->is_nullable($c->{NULLABLE} == 1);
                $f->is_auto_increment($is_auto_increment);
                if ( defined $c->{COLUMN_DEF}) {
                  $c->{COLUMN_DEF} =~ s#\('?(.*?)'?\)#$1#;
                  $f->default_value($c->{COLUMN_DEF});
                }
            }

            # add in primary key
            my $h = $dbh->selectall_hashref("sp_pkeys
[$table_info->{TABLE_NAME}]", 'COLUMN_NAME');
            if (scalar keys %{$h} >= 1) {
                my @c = map {
                    $_->{COLUMN_NAME}
                } sort {
                    $a->{KEY_SEQ} <=> $b->{KEY_SEQ}
                } values %{$h};

                $table->primary_key(@c)
                    if (scalar @c);
            }

            # add in foreign keys
            $h = $dbh->selectall_hashref("sp_fkeys NULL,
\@fktable_name = '[$table_info->{TABLE_NAME}]'", 'FK_NAME');
         foreach my $fk ( values %{$h} ) {
            my $constraint = $table->add_constraint( name => $fk->{FK_NAME},
               fields => [$fk->{FKCOLUMN_NAME}],
            );
            $constraint->type("FOREIGN_KEY");
            $constraint->on_delete(
               $fk->{DELETE_RULE} == 0 ? "CASCADE" :
               $fk->{DELETE_RULE} == 1 ? "NO ACTION" : "SET_NULL"
            );
            $constraint->on_update(
               $fk->{UPDATE_RULE} == 0 ? "CASCADE" :
               $fk->{UPDATE_RULE} == 1 ? "NO ACTION" : "SET_NULL"
            );
            $constraint->reference_table($fk->{PKTABLE_NAME});
         }

            # add in any indexes ... how do we tell if the index has
            # already been created as part of a primary key or other
            # constraint?

            if (defined($stuff->{indexes}->{$table_info->{TABLE_NAME}})){
                my $h = $dbh->selectall_hashref("sp_helpindex
[$table_info->{TABLE_NAME}]", 'INDEX_NAME');
                foreach (values %{$h}) {
                    my $fields = $_->{'INDEX_KEYS'};
                    $fields =~ s/\s*//g;
                    my $i = $table->add_index(
                                              name   =>
$_->{INDEX_NAME},
                                              fields => $fields,
                                             );
                    if ($_->{'INDEX_DESCRIPTION'} =~ /unique/i) {
                        $i->type('unique');

                        # we could make this a primary key if there
                        # isn't already one defined and if there
                        # aren't any nullable columns in thisindex.

                        if (!defined($table->primary_key())) {
                            $table->primary_key($fields)
                                unless grep {
                                    $table->get_field($_)->is_nullable()
                                } split(/,\s*/, $fields);
                        }
                    }
                }
            }
        } elsif ($table_info->{TABLE_TYPE} eq 'VIEW') {
         next if $table_info->{TABLE_NAME} eq 'sysconstraints'
            || $table_info->{TABLE_NAME} eq 'syssegments';
         next if !$stuff->{view}->{$table_info->{TABLE_NAME}}->{text};
            my $view =  $schema->add_view(
                                          name =>
$table_info->{TABLE_NAME},
                                          );


            my $cols =
                $columns->{$table_info->{TABLE_CAT}}
                    ->{$table_info->{TABLE_SCHEM}}
                        ->{$table_info->{TABLE_NAME}}
                            ->{columns};

            $view->fields(map {
                $_->{COLUMN_NAME}
            } sort {
                $a->{ORDINAL_POSITION} <=> $b->{ORDINAL_POSITION}
                } values %{$cols}
                         );

            $view->sql($stuff->{view}->{$table_info->{TABLE_NAME}}->{text})
                if (defined($stuff->{view}->{$table_info->{TABLE_NAME}}->{text}));
        }
    }

    foreach my $p (values %{$stuff->{procedures}}) {
      next if !$p->{text};
        my $proc = $schema->add_procedure(
                               name      => $p->{name},
                               owner     => $p->{PROCEDURE_OWNER},
                               comments  => $p->{REMARKS},
                               sql       => $p->{text},
                               );

    }

    ### Permissions
    ### Groups
    ### Users
    ### Aliases
    ### Logins
    return 1;
}

1;

=pod

=head1 AUTHOR

Chris Hilton E<lt>chris@dctank.comE<gt> - Bulk of code from
DBI-Sybase parser, I just tweaked it for SQLServer. Thanks.

=head1 SEE ALSO

DBI, DBD::ODBC, SQL::Translator::Schema.

=cut