package Text::Playlist::XSPF;

use strict;
use warnings;
use feature qw(switch);
use utf8;

use base 'Text::Playlist';

use XML::XPath;

our $VERSION = 0.1;

sub new {
  my ($class) = @_;

  return bless({ items => [], version => 0 }, $class);
}

sub add {
  my ($self, %args) = @_;

  foreach my $key (qw(title location)) {
    next if $args{$key};
    return "Missing '$key' parameter";
  }

  $self->{items} //= [];
  push @{$self->{items}}, {
    title    => $args{title},
    location => $args{location},
  };

  return;
}

sub parse {
  my ($self, $text) = @_;
  my @items = ();

  my $xp = XML::XPath->new(xml => $text);
  if (my $vers = $xp->find('/playlist/@version')) {
    $self->{version} = $vers;
  } else {
    return "Can't find playlist version";
  }

  my $tracks = $xp->find('/playlist/trackList/track');
  foreach my $track ($tracks->get_nodelist) {
    my $item = {};
    foreach my $child ($track->getChildNodes) {
      next unless (ref $child eq 'XML::XPath::Node::Element');
      my $value = $child->string_value();
      given ($child->getName()) {
        when (m/title/oi)    { $item->{title}    = $value; }
        when (m/location/oi) { $item->{location} = $value; }
        default { warn "garbage inside <track> element: $_ -> $value\n"; }
      }
    }
    unless ($item->{title} and $item->{location}) {
      warn "Missing mandatory 'title' or 'location' field\n";
      next;
    }
    push @items, $item;
  }

  return wantarray ? @items : [ @items ];
}

sub dump { die("dump() unimplemented for XSPF format\n"); }

1;

__END__

=pod

=head1 LINKS

  L<https://en.wikipedia.org/wiki/XML_Shareable_Playlist_Format>

=cut