(in-package #:lempel)

(defun compress-file (input-path output-path)
  (let ((file (str:read-file input-path)))
    (with-open-file (output output-path
                            :direction :output
                            :if-does-not-exist :create
                            :if-exists :supersede
                            :element-type '(unsigned-byte 8))
      (write-sequence (prefix-encode (compress file) #xAE) output)))
  t)

(defun decompress-file (input-path output-path)
  (let ((file (read-file input-path)))
    (with-open-file (output output-path
                            :direction :output
                            :if-does-not-exist :create
                            :if-exists :supersede
                            :element-type :default)
      (write-sequence (prefix-decode file #xAE) output)))
  t)

(declaim (ftype (function (string) (array (unsigned-byte 8))) read-file))
(defun read-file (path)
  (with-open-file (file path :element-type '(unsigned-byte 8))
    (let* ((size (file-length file))
           (buf (make-array size :element-type '(unsigned-byte 8))))
      (read-sequence buf file)
      buf)))