=head1 NAME

SuikaWiki::DB::Hash --- SuikaWiki WikiDatabase: WikiDatabase interface wrapper for hash

=head1 DESCRIPTION

This module wrappes perl's hash with WikiDatabase common interface of
SuikaWiki.  It is useful for tied hash.

This module is part of SuikaWiki.

=cut

package SuikaWiki::DB::Hash;
require SuikaWiki::DB::Util;

sub new ($%) {
  my ($class, %o) = @_;
  my $self = bless {}, $class;
  if ($o{-lock}) {
    $self->{lock} = SuikaWiki::DB::Util->new_lock ($self->{-lock});
    $self->{lock}->lock;
  }
  $self->{error} = SuikaWiki::DB::Util->error_handler;
  $self->{db_hash} = &{$o{constructor} || sub {return {}}} ($self, \%opt);
  unless ($self->{db_hash}) {
    $self->{error}->raise (type => 'DB_OPEN');
  }
  $self->{has_exist} = defined $o{has_exist} ? $o{has_exist} : 1;
  $self;
}

sub get ($$$) {
  my ($self, $prop, $key) = @_;
  if (scalar @$key > 1) {
    $self->{error}->raise (type => 'KEY_INVALID_NAME', key => $key);
  } else {
    $self->{db_hash}->{$key->[0]};
  }
}

sub set ($$$$) {
  my ($self, $prop, $key => $value) = @_;
  if (scalar @$key > 1) {
    $self->{error}->raise (type => 'KEY_INVALID_NAME', key => $key);
  } else {
    $self->{db_hash}->{$key->[0]} = $value;
  }
}

sub exist ($$$) {
  my ($self, $prop, $key) = @_;
  if (scalar @$key > 1) {
    $self->{error}->raise (type => 'KEY_INVALID_NAME', key => $key);
  } else {
    if ($self->{has_exist}) {
      return exist $self->{db_hash}->{$key->[0]};
    } else {
      return defined $self->{db_hash}->{$key->[0]} ? 1 : 0;
    }
  }
}

sub delete ($$$) {
  my ($self, $prop, $key) = @_;
  if (scalar @$key > 1) {
    $self->{error}->raise (type => 'KEY_INVALID_NAME', key => $key);
  } else {
    delete $self->{db_hash}->{$key->[0]};
  }
}

sub keys ($$;%) {
  my ($self, $prop, %opt) = @_;
  if (scalar @{$opt{ns}} > 1) {
    $self->{error}->raise (type => 'KEY_INVALID_NAME', key => $key);
  } else {
    return map {[$_]} keys %{$self->{db_hash}};
  }
}

sub close ($) {
  my $self = shift;
  &{$self->{destructor} || sub { 1 }} ($self)
    or $self->{error}->raise (type => 'DB_CLOSE');
  $self->{db_hash} = undef;
}
	   
sub DESTROY ($) {
  my $self = shift;
  $self->close if $self->{db_hash};
}

=head1 METHODS

This module provides common interface of SuikaWiki WikiDatabase
modules. See C<SuikaWiki::DB>.

=head1 AUTHOR

Wakaba <w@suika.fam.cx>.

=head1 LICENSE

Copyright 2003 Wakaba <w@suika.fam.cx>

This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.

=cut

1; # $Date: 2003/08/06 01:26:14 $