package AcceptLang;     # vim:ft=perl:

# available languages and order
my @langs = ('de', 'en');

# default lang if no requested language is available
my $defaultlang = 'en';


sub start {
    1;
}

sub filter {
    my $self = shift;
    my ($files, $others) = @_;
    my $acceptlang = $ENV{'HTTP_ACCEPT_LANGUAGE'} ? $ENV{'HTTP_ACCEPT_LANGUAGE'} : $defaultlang;

    my @order = parse($acceptlang, @langs);
    $blosxom::blog_language = $order[0];
    foreach (keys %$files) {
        delete $files->{$_} unless (
            /^[^.]+\.$order[0]\.$blosxom::file_extension$/ or
            /^[^.]+\.$blosxom::file_extension$/
        );
    }
};

sub parse {
    my ($acceptlang, @langs) = @_;

    # dumb parsing, good enough for a first start
    #my (@order) = $acceptlang =~ /^(?:\s*([^,;]+)[^,]*,)*\s*([^,;]+)[^,]*$/;
    # doesn't work -- for now only take the first entry
    my (@order) = $acceptlang =~ /^\s*([^,;]+)/;

    my $langs = join('|', @langs);

    return grep { /^$langs$/ } @order;
}

1;

__END__

    use Data::Dumper;
    open FOO, ">/tmp/blaaah" or die "$0: can't write to /tmp/blaaah: $!";
    print FOO Dumper(\@_, \@order);
    close FOO;