dtRdr::Library - library class frontend/base

  dtRdr::Library->class_by_type($type);

  my $library = dtRdr::Library->new();

  my @infos = $lib->get_book_info;

  $lib->open_book(intid => $id);

  $lib->open_book(title => $title);

  $lib->open_book(book_id => $book_id);

  $info = $lib->find_book_by($key, $value);

  $lib->delete_metadata($book, $metadata);

package dtRdr::Library;
$VERSION = eval{require version}?version::qv($_):$_ for(0.0.1);

use warnings;
use strict;
use Carp;

# somebody said "use Universal", so bah
sub import {}

use dtRdr::Library::YAMLLibrary; # XXX need plugin loader here

# NOTE I think all of these should be read-only, since the underlying
# implementation typically needs to save the attributes if they change.
# TODO use setter sub {shift->_saveval(@_);} # or so
use Class::Accessor::Classy;
ro 'id';
ro 'name';
ro 'type';
ro 'location';
rw 'book_data'; # XXX should be ro?
ro 'directory';
no  Class::Accessor::Classy;
{
  package dtRdr::LibraryData::BookInfo;
  use Class::Accessor::Classy;
  with 'new';
  ro 'intid';
  ro 'book_id';
  ro 'title';
  ro 'uri';
  ro 'type';
  ro 'library';
  no  Class::Accessor::Classy;
  # TODO id re-arranging metheds swap_id, move_before -- callbacks to library
}
# and maybe...
# {
#   package dtRdr::LibraryData::LibraryInfo;
#   use Class::Accessor::Classy;
#   with 'new';
#   ro 'id';
#   ro 'name';
#   no  Class::Accessor::Classy;
# }

# The default structure of a library object is a hash. The following
# are the standard elements:
#
# books = array ref of book objects
# metadata = array ref of metadata objects
# library_info = Book info hashes
#
# Subclass methods:
#
# _load_books - should load in the basic book info from whatever
#               backing store that they're in. Does not create book
#               objects, but does load in the info the library needs
#               to load in the book objects
	# NOTE let's call these "book handles" --Eric
#
# _load_metadata - Load in all the metadata objects from the library
#
# _load_book_objects - Load in all the book objects for the books in
#                      the library

use dtRdr::Traits::Class qw(
  NOT_IMPLEMENTED
  );

sub class_by_type {
  my $self = shift;
  my ($type) = @_;

  # XXX any color of black...
  return('dtRdr::Library::' . $type);
} # end subroutine class_by_type definition
########################################################################

sub new {
  my $package = shift;
  my $class = ref($package) || $package;
  my $self = {
    metadata => [],
    # books    => [], # XXX need to be able to do this here
    library_info => {},
	  };
  bless($self, $class);
  return($self);
} # end subroutine new definition
########################################################################

sub load_uri { my $self = shift; $self->NOT_IMPLEMENTED(@_); }

sub get_books {
  my $self = shift;
  if (!defined $self->{books}) {
    $self->_load_book_objects;
  }
  return @{$self->{books}};
} # end subroutine get_books definition
########################################################################

sub get_metadata {
  my $self = shift;
  if(defined $self->{metadata}) {
    return @{$self->{metadata}};
  }
  else { # this wasn't even returning a value!
    do('./util/BREAK_THIS') or die;
    $self->_fetch_all_metadata();
  }
}

sub get_book_info {
  my $self = shift;
  return @{$self->book_data};
}

sub open_book {
  my $self = shift;
  (@_ % 2) and croak('odd number of elements in argument list');
  my (%args) = @_;
  my @valid = qw(intid title book_id);
  my ($key) = grep({exists($args{$_})} @valid);
  $key or croak('no valid key (',
    join(', ', @valid), ') in arguments: (', join(',', keys(%args)), ')');

  my @books = $self->find_book_by($key, $args{$key});
  @books or die "no books matching $key eq $args{$key}";
  (@books == 1) or die "too many books @books";
  my $B = $books[0];
  # this will get us by until config is operable
  # (and shouldn't break after it works either)
  require dtRdr::Plugins::Book;
  dtRdr::Plugins::Book->init();

  # requires that config sets type -> class prefs
  my $book_class = dtRdr::Plugins::Book->class_for_type($B->type);
  $book_class or die "cannot get a plugin for $B->{type}";
  0 and warn "book class: $book_class";
  my $book_object = $book_class->new();

  # TODO add abstraction somewhere in here
  #      (e.g. it might be http://, absolute, etc)
  my $uri = $self->directory . '/' . $B->uri;
  # NOTE:  Do not be tempted to (-e $uri) here, let the book die.
  0 and warn "book is $uri";
  $book_object->load_uri($uri);

  # XXX does it need the library?
  # $book_object->set('library', $self);

  return($book_object);
} # end subroutine open_book definition
########################################################################

sub find_book_by { my $self = shift; $self->NOT_IMPLEMENTED(@_); }

sub add_metadata { my $self = shift; $self->NOT_IMPLEMENTED(@_); }

sub delete_metadata { my $self = shift; $self->NOT_IMPLEMENTED(@_); }

sub add_book { my $self = shift; $self->NOT_IMPLEMENTED(@_); }

sub remove_book { my $self = shift; $self->NOT_IMPLEMENTED(@_); }

1;
# vim:ts=2:sw=2:et:sta