package Db::ShellBackend;

#
# This package abstracts the common needs of the
# PostgresqlShellDbBackend and MysqlShellDbBackend: both packages need
# to process fetched result data.
#
# Subclasses must use _set_execute_result() method in their execute() methods.
# It accepts the reference to the array of references to the arrays of data
# $data->[0] must refer to the array of columns, and $data->[1] etc - to the arrays of data.
#

use strict;
use Db::Backend;

use vars qw|@ISA|;

@ISA = qw|Db::Backend|;

sub disconnect {
}

sub _set_execute_result {
  my ($self, $data) = @_;

  $self->{columns} = shift @{$data};
  $self->{res} = $data;
  $self->{index} = 0;
}

sub rownum {
  my ($self) = @_;
  return scalar(@{$self->{res}});
}

sub fetchrow {
  my ($self) = @_;

  return if $self->{index} >= @{$self->{res}};

  return $self->{res}->[$self->{index}++];
}

sub fetchhash {
  my ($self) = @_;

  my $row = $self->fetchrow();
  return if !$row;

  my $res = {};
  for (my $i = 0; $i < @{$self->{columns}}; ++$i) {
    $res->{$self->{columns}->[$i]} = $row->[$i];
  }

  return $res;
}

sub finish {
  my ($self) = @_;

  delete $self->{columns};
  delete $self->{res};
  delete $self->{index};
}

# noop
sub ping {
  return 1;
}

sub _setDumpCmdline {
  my ($self, $dumpCmdline) = @_;
  $self->{dumpCmdline} = $dumpCmdline;
}

sub dumpCmdline {
  my ($self) = @_;

  return $self->{dumpCmdline};
}

sub _setFileToRemove {
  my ($self, $file) = @_;
  push @{$self->{fileToRemove}}, $file;
}

sub getFileToRemove {
  my ($self) = @_;
  return @{$self->{fileToRemove}};
}

1;