#! perl

=head1 CF+ map maker library and utilities

=over 4

=cut
# This extension loads some nice functionality for map makers

sub rec_inv_by_slaying {
   my ($ob, $slaying, $cb) = @_;
   $cb->($ob) if $ob->slaying eq $slaying;
   for my $iob ($ob->inv) { rec_inv_by_slaying ($iob, $slaying, $cb) }
}

=item object attachment: 'check_inventory_on_apply'

This attachment checks on apply whether the applyer
has a specific item. Currently you can only match the slaying
field of the inventory item of the player.

On match the apply isn't inhibited.

Following configuration can be supplied to this attachment:

=over 4

=item key_string

This is the string that will be matched against the slaying field
of the inventory item of the player. The first found item will be
decreased by the amount that can be passed in the 'decrease_by_cnt'
option.

=item decrease_by_cnt

This is the amount the matching object will be decreased by from the inventory.
Default is 0 and means nothing will be removed.

=item message_on_match

This is the message that will printed to the player if a matching
object was found.

=item message_on_nomatch

This is the message that will printed to the player if NO matching
object was found.

=back

=cut

cf::object::attachment check_inventory_on_apply =>
   on_apply => sub {
      my ($self, $pl) = @_;
      my $cfg = $self->{check_inventory_on_apply};
      my $match;
      rec_inv_by_slaying ($pl, $cfg->{key_string}, sub {
         my ($ob) = @_;
         $match = $ob;
      });
      if ($match) {
         $match->decrease_ob_nr ($cfg->{decrease_by_cnt}) if $cfg->{decrease_by_cnt};
         $pl->message ($cfg->{message_on_match}, cf::NDI_UNIQUE) if defined $cfg->{message_on_match};
      } else {
         $pl->message ($cfg->{message_on_nomatch}, cf::NDI_RED | cf::NDI_UNIQUE) if defined $cfg->{message_on_nomatch};
         cf::override;
      }
   };

=back

=cut