{
package DBD::Sponge;

require DBI;
require Carp;

our @EXPORT = qw(); # Do NOT @EXPORT anything.
our $VERSION = "12.010003";

# $Id: Sponge.pm 10002 2007-09-26 21:03:25Z Tim $
#
# Copyright (c) 1994-2003 Tim Bunce Ireland
#
# You may distribute under the terms of either the GNU General Public
# License or the Artistic License, as specified in the Perl README file.

$drh = undef; # holds driver handle once initialised
my $methods_already_installed;

sub driver{
return $drh if $drh;

DBD::Sponge::db->install_method("sponge_test_installed_method")
unless $methods_already_installed++;

my($class, $attr) = @_;
$class .= "::dr";
($drh) = DBI::_new_drh($class, {
'Name' => 'Sponge',
'Version' => $VERSION,
'Attribution' => "DBD::Sponge $VERSION (fake cursor driver) by Tim Bunce",
});
$drh;
}

sub CLONE {
undef $drh;
}
}


{ package DBD::Sponge::dr; # ====== DRIVER ======
$imp_data_size = 0;
# we use default (dummy) connect method
}


{ package DBD::Sponge::db; # ====== DATABASE ======
$imp_data_size = 0;
use strict;

sub prepare {
my($dbh, $statement, $attribs) = @_;
my $rows = delete $attribs->{'rows'}
or return $dbh->set_err($DBI::stderr,"No rows attribute supplied to prepare");
my ($outer, $sth) = DBI::_new_sth($dbh, {
'Statement' => $statement,
'rows' => $rows,
(map { exists $attribs->{$_} ? ($_=>$attribs->{$_}) : () }
qw(execute_hook)
),
});
if (my $behave_like = $attribs->{behave_like}) {
$outer->{$_} = $behave_like->{$_}
foreach (qw(RaiseError PrintError HandleError ShowErrorStatement));
}

if ($statement =~ /^\s*insert\b/) { # very basic, just for testing execute_array()
$sth->{is_insert} = 1;
my $NUM_OF_PARAMS = $attribs->{NUM_OF_PARAMS}
or return $dbh->set_err($DBI::stderr,"NUM_OF_PARAMS not specified for INSERT statement");
$sth->STORE('NUM_OF_PARAMS' => $attribs->{NUM_OF_PARAMS} );
}
else { #assume select

# we need to set NUM_OF_FIELDS
my $numFields;
if ($attribs->{'NUM_OF_FIELDS'}) {
$numFields = $attribs->{'NUM_OF_FIELDS'};
} elsif ($attribs->{'NAME'}) {
$numFields = @{$attribs->{NAME}};
} elsif ($attribs->{'TYPE'}) {
$numFields = @{$attribs->{TYPE}};
} elsif (my $firstrow = $rows->[0]) {
$numFields = scalar @$firstrow;
} else {
return $dbh->set_err($DBI::stderr, 'Cannot determine NUM_OF_FIELDS');
}
$sth->STORE('NUM_OF_FIELDS' => $numFields);
$sth->{NAME} = $attribs->{NAME}
|| [ map { "col$_" } 1..$numFields ];
$sth->{TYPE} = $attribs->{TYPE}
|| [ (DBI::SQL_VARCHAR()) x $numFields ];
$sth->{PRECISION} = $attribs->{PRECISION}
|| [ map { length($sth->{NAME}->[$_]) } 0..$numFields -1 ];
$sth->{SCALE} = $attribs->{SCALE}
|| [ (0) x $numFields ];
$sth->{NULLABLE} = $attribs->{NULLABLE}
|| [ (2) x $numFields ];
}

$outer;
}

sub type_info_all {
my ($dbh) = @_;
my $ti = [
{ TYPE_NAME => 0,
DATA_TYPE => 1,
PRECISION => 2,
LITERAL_PREFIX => 3,
LITERAL_SUFFIX => 4,
CREATE_PARAMS => 5,
NULLABLE => 6,
CASE_SENSITIVE => 7,
SEARCHABLE => 8,
UNSIGNED_ATTRIBUTE=> 9,
MONEY => 10,
AUTO_INCREMENT => 11,
LOCAL_TYPE_NAME => 12,
MINIMUM_SCALE => 13,
MAXIMUM_SCALE => 14,
},
[ 'VARCHAR', DBI::SQL_VARCHAR(), undef, "'","'", undef, 0, 1, 1, 0, 0,0,undef,0,0 ],
];
return $ti;
}

sub FETCH {
my ($dbh, $attrib) = @_;
# In reality this would interrogate the database engine to
# either return dynamic values that cannot be precomputed
# or fetch and cache attribute values too expensive to prefetch.
return 1 if $attrib eq 'AutoCommit';
# else pass up to DBI to handle
return $dbh->SUPER::FETCH($attrib);
}

sub STORE {
my ($dbh, $attrib, $value) = @_;
# would normally validate and only store known attributes
# else pass up to DBI to handle
if ($attrib eq 'AutoCommit') {
return 1 if $value; # is already set
Carp::croak("Can't disable AutoCommit");
}
return $dbh->SUPER::STORE($attrib, $value);
}

sub sponge_test_installed_method {
my ($dbh, @args) = @_;
return $dbh->set_err(42, "not enough parameters") unless @args >= 2;
return \@args;
}
}


{ package DBD::Sponge::st; # ====== STATEMENT ======
$imp_data_size = 0;
use strict;

sub execute {
my $sth = shift;

# hack to support ParamValues (when not using bind_param)
$sth->{ParamValues} = (@_) ? { map { $_ => $_[$_-1] } 1..@_ } : undef;

if (my $hook = $sth->{execute_hook}) {
&$hook($sth, @_) or return;
}

if ($sth->{is_insert}) {
my $row;
$row = (@_) ? [ @_ ] : die "bind_param not supported yet" ;
my $NUM_OF_PARAMS = $sth->{NUM_OF_PARAMS};
return $sth->set_err($DBI::stderr, @$row." values bound (@$row) but $NUM_OF_PARAMS expected")
if @$row != $NUM_OF_PARAMS;
{ local $^W; $sth->trace_msg("inserting (@$row)\n"); }
push @{ $sth->{rows} }, $row;
}
else { # mark select sth as Active
$sth->STORE(Active => 1);
}
# else do nothing for select as data is already in $sth->{rows}
return 1;
}

sub fetch {
my ($sth) = @_;
my $row = shift @{$sth->{'rows'}};
unless ($row) {
$sth->STORE(Active => 0);
return undef;
}
return $sth->_set_fbav($row);
}
*fetchrow_arrayref = \&fetch;

sub FETCH {
my ($sth, $attrib) = @_;
# would normally validate and only fetch known attributes
# else pass up to DBI to handle
return $sth->SUPER::FETCH($attrib);
}

sub STORE {
my ($sth, $attrib, $value) = @_;
# would normally validate and only store known attributes
# else pass up to DBI to handle
return $sth->SUPER::STORE($attrib, $value);
}
}

1;

__END__

=pod

=head1 NAME

DBD::Sponge - Create a DBI statement handle from Perl data

=head1 SYNOPSIS

my $sponge = DBI->connect("dbi:Sponge:","","",{ RaiseError => 1 });
my $sth = $sponge->prepare($statement, {
rows => $data,
NAME => $names,
%attr
}
);

=head1 DESCRIPTION

DBD::Sponge is useful for making a Perl data structure accessible through a
standard DBI statement handle. This may be useful to DBD module authors who
need to transform data in this way.

=head1 METHODS

=head2 connect()

my $sponge = DBI->connect("dbi:Sponge:","","",{ RaiseError => 1 });

Here's a sample syntax for creating a database handle for the Sponge driver.
No username and password are needed.

=head2 prepare()

my $sth = $sponge->prepare($statement, {
rows => $data,
NAME => $names,
%attr
}
);

=over 4

=item *

The C<$statement> here is an arbitrary statement or name you want
to provide as identity of your data. If you're using DBI::Profile
it will appear in the profile data.

Generally it's expected that you are preparing a statement handle
as if a C<select> statement happened.

=item *

C<$data> is a reference to the data you are providing, given as an array of arrays.

=item *

C<$names> is a reference an array of column names for the C<$data> you are providing.
The number and order should match the number and ordering of the C<$data> columns.

=item *

C<%attr> is a hash of other standard DBI attributes that you might pass to a prepare statement.

Currently only NAME, TYPE, and PRECISION are supported.

=back

=head1 BUGS

Using this module to prepare INSERT-like statements is not currently documented.

=head1 AUTHOR AND COPYRIGHT

This module is Copyright (c) 2003 Tim Bunce

Documentation initially written by Mark Stosberg

The DBD::Sponge module is free software; you can redistribute it and/or
modify it under the same terms as Perl itself. In particular permission
is granted to Tim Bunce for distributing this as a part of the DBI.

=head1 SEE ALSO

L<DBI>

=cut