func NewWriter(w io.Writer) *Writer {
	return &Writer{w: w, curr: &regFileWriter{w, 0}}
}

type fileWriter interface {
	io.Writer
	fileState

	ReadFrom(io.Reader) (int64, error)
}

// Flush finishes writing the current file's block padding.
// The current file must be fully written before Flush can be called.
//
// This is unnecessary as the next call to [Writer.WriteHeader] or [Writer.Close]

func (w *Writer) SetComment(comment string) error {
	if len(comment) > uint16max {
		return errors.New("zip: Writer.Comment too long")
	}
	w.comment = comment
	return nil
}

// Close finishes writing the zip file by writing the central directory.
// It does not close the underlying writer.
func (w *Writer) Close() error {
	if w.last != nil && !w.last.closed {
		if err := w.last.close(); err != nil {
			return err