sub unicode_trim {
    my ( $unicode, $len ) = @_;
    return '' if $len <= 0;
    my $gcs = Unicode::GCString->new( $unicode );
    my $pos = $gcs->pos;
    $gcs->pos( 0 );
    my $cols = 0;
    my $gc;
    while ( defined( $gc = $gcs->next ) ) {
        if ( $len < ( $cols += $gc->columns ) ) {
            my $ret = $gcs->substr( 0, $gcs->pos - 1 );
            $gcs->pos( $pos );
            return $ret->as_string;
        }
    }
    $gcs->pos( $pos );
    return $gcs->as_string;
}

sub unicode_sprintf {
    my ( $unicode, $avail_width, $right_justify ) = @_;
    my $gcs = Unicode::GCString->new( $unicode );
    my $colwidth = $gcs->columns;
    if ( $colwidth > $avail_width ) {
        my $pos = $gcs->pos;
        $gcs->pos( 0 );
        my $cols = 0;
        my $gc;
        while ( defined( $gc = $gcs->next ) ) {
            if ( $avail_width < ( $cols += $gc->columns ) ) {
                my $ret = $gcs->substr( 0, $gcs->pos - 1 );
                $gcs->pos( $pos );
                return $ret->as_string;
            }
        }
    }
    elsif ( $colwidth < $avail_width ) {
        if ( $right_justify ) {
            $unicode = " " x ( $avail_width - $colwidth ) . $unicode;
        }
        else {
            $unicode = $unicode . " " x ( $avail_width - $colwidth );
        }
    }
    return $unicode;
}