Find cmap based on caller-specified order of preference [updated]

customCmapSearch.pl

use strict;
use Font::TTF::Font;

sub find_cmap
{
    my ($f, $order) = @_;
    # Should do parameter validation here

    my ($cmap, %cmaps, $i);
    
    $cmap = $f->{'cmap'}->read;
    for ($i = 0; $i < $cmap->{'Num'}; $i++)
    {
        my $s = $cmap->{'Tables'}[$i];
        my $key = "$s->{'Platform'}/$s->{'Encoding'}";
        $cmaps{$key} = $s;
        print "candidate: $key\n";
    }
    
    foreach (@{$order})
    {
        if (exists $cmaps{$_})
        {
            $cmap->{' mstable'} = $cmaps{$_};
            last;
        }
    }
    $cmap->{' mstable'};
}
  
my $fontfile = $ARGV[0] || "NotoSansJP-Regular.otf";
my $f = Font::TTF::Font->open($fontfile) || die "error opening TrueType font '$fontfile'.\n";
my $cmap = find_cmap($f, [qw( 0/6 0/4 3/10 0/3 3/1)]);
die "No useful cmap found" unless $cmap;

printf "found: %d/%d\n", $cmap->{'Platform'}, $cmap->{'Encoding'};