package Font::TTF::Fdsc;

=head1 NAME

Font::TTF::Fdsc - Font Descriptors table in a font

=head1 DESCRIPTION

=head1 INSTANCE VARIABLES

=over

=item version

=item descriptors

Hash keyed by descriptor tags

=back 

=head1 METHODS

=cut

use strict;
use vars qw(@ISA %fields);
use Font::TTF::Utils;

@ISA = qw(Font::TTF::Table);

=head2 $t->read

Reads the table into memory

=cut

sub read
{
    my ($self) = @_;
    my ($dat, $fh, $numDescs, $tag, $descs);

    $self->SUPER::read or return $self;

    $fh = $self->{' INFILE'};
    $fh->read($dat, 4);
    $self->{'version'} = TTF_Unpack("v", $dat);

    $fh->read($dat, 4);

    foreach (1 .. unpack("N", $dat)) {
        $fh->read($tag, 4);
        $fh->read($dat, 4);
        $descs->{$tag} = ($tag eq 'nalf') ? unpack("N", $dat) : TTF_Unpack("f", $dat);
    }

    $self->{'descriptors'} = $descs;

    $self;
}


=head2 $t->out($fh)

Writes the table to a file either from memory or by copying

=cut

sub out
{
    my ($self, $fh) = @_;
    my ($descs);

    return $self->SUPER::out($fh) unless $self->{' read'};
    
    $fh->print(TTF_Pack("v", $self->{'version'}));
    
    $descs = $self->{'descriptors'} or {};
    
    $fh->print(pack("N", scalar keys %$descs));    
    foreach (sort keys %$descs) {
        $fh->print($_);
        $fh->print(($_ eq 'nalf') ? pack("N", $descs->{$_}) : TTF_Pack("f", $descs->{$_}));
    }

    $self;
}

=head2 $t->print($fh)

Prints a human-readable representation of the table

=cut

sub print
{
    my ($self, $fh) = @_;
    my ($descs, $k);

    $self->read;

    $fh = 'STDOUT' unless defined $fh;

    $descs = $self->{'descriptors'};
    foreach $k (sort keys %$descs) {
        if ($k eq 'nalf') {
            $fh->printf("Descriptor '%s' = %d\n", $k, $descs->{$k});
        }
        else {
            $fh->printf("Descriptor '%s' = %f\n", $k, $descs->{$k});
        }
    }
    
    $self;
}

1;


=head1 BUGS

None known

=head1 AUTHOR

Jonathan Kew L<Jonathan_Kew@sil.org>. 


=head1 LICENSING

Copyright (c) 1998-2013, SIL International (http://www.sil.org) 

This module is released under the terms of the Artistic License 2.0. 
For details, see the full text of the license in the file LICENSE.

The test suite contains test fonts released under the SIL Open Font License 1.1, see OFL.txt.

=cut