=head1 NAME

Mail::SpamAssassin::PersistentAddrList - persistent address list base class

=head1 SYNOPSIS

  my $factory = PersistentAddrListSubclass->new();
  $spamtest->set_persistent_addr_list_factory ($factory);
  ... call into SpamAssassin classes...

SpamAssassin will call:

  my $addrlist = $factory->new_checker($spamtest);
  $entry = $addrlist->get_addr_entry ($addr);
  ...

=head1 DESCRIPTION

All persistent address list implementations, used by the auto-whitelist
code to track known-good email addresses, use this as a base class.

See C<Mail::SpamAssassin::DBBasedAddrList> for an example.

=head1 METHODS

=over 4

=cut

package Mail::SpamAssassin::PersistentAddrList;

use strict;
use bytes;

use vars qw{
  @ISA
};

@ISA = qw();

###########################################################################

=item $factory = PersistentAddrListSubclass->new();

This creates a factory object, which SpamAssassin will call to create
a new checker object for the persistent address list.

=cut

sub new {
  my $class = shift;
  $class = ref($class) || $class;
  my $self = { };
  bless ($self, $class);
  $self;
}

###########################################################################

=item my $addrlist = $factory->new_checker();

Create a new address-list checker object from the factory. Called by the
SpamAssassin classes.

=cut 

sub new_checker {
  my ($factory, $main) = @_;
  die "unimpled base method";	# override this
}

###########################################################################

=item $entry = $addrlist->get_addr_entry ($addr);

Given an email address C<$addr>, return an entry object with the details of
that address.

The entry object is a reference to a hash, which must contain at least
two keys: C<count>, which is the count of times that address has been
encountered before; and C<totscore>, which is the total of all scores for
messages associated with that address.  From these two fields, an average
score will be calculated, and the score for the current message will be
regressed towards that mean message score.

The hash can contain whatever other data your back-end needs to store,
under other keys.

The method should never return C<undef>, or a hash that does not contain
a C<count> key and a C<totscore> key.

=cut 

sub get_addr_entry {
  my ($self, $addr) = @_;
  my $entry = { };
  die "unimpled base method";	# override this
  return $entry;
}

###########################################################################

=item $entry = $addrlist->add_score($entry, $score);

This method should add the given score to the whitelist database for the
given entry, and then return the new entry.

=cut

sub add_score {
    my ($self, $entry, $score) = @_;
    die "unimpled base method"; # override this
}

###########################################################################

=item $entry = $addrlist->remove_entry ($entry);

This method should remove the given entry from the whitelist database.

=cut

sub remove_entry {
  my ($self, $entry) = @_;
  die "unimpled base method";	# override this
}

###########################################################################

=item $entry = $addrlist->finish ();

Clean up, if necessary.  Called by SpamAssassin when it has finished
checking, or adding to, the auto-whitelist database.

=cut

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

###########################################################################

1;