(use-modules (ice-9 pretty-print))
(use-modules (ice-9 binary-ports))
(use-modules (ice-9 match))

(define filename (match (command-line)
		   ((self file) file)))

(define* (package-list port #:optional (init '()))
  (let ((start (ftell port))
	(sexp (read port))
	(end (ftell port)))
    (if (eof-object? sexp)
	init
	(package-list port (cons (list start end sexp)  init)))))

(define out-port (current-output-port))
(define port (open-file filename "r"))
(define packages (package-list port))
(define sorted-packages
  (sort-list
   packages
   (match-lambda* (((_ _ ('define-public names _)) ...)
		   (apply string<? (map symbol->string names)))
		  (_ #t))))

(define (write-packages packages in-port out-port)
  (for-each (match-lambda
	      ((start end _)
	       (let* ((len (- end start)))
		 (seek in-port start SEEK_SET)
		 (put-bytevector
		  out-port
		  (get-bytevector-n port len)))))
	    packages))

(write-packages sorted-packages port out-port)