#! ./pre-inst-env
!#
(use-modules (ice-9 format)
             (ice-9 futures)
             (ice-9 getopt-long)
             (ice-9 ftw))

(let* ((option-spec
        '((settings (single-char #\s) (value #t))
          (output (single-char #\o) (value #t))
          (documentation (single-char #\d) (value #t))))
       (options (getopt-long (command-line) option-spec))
       (settings (option-ref options 'settings #f))
       (output (option-ref options 'output #f))
       (documentation (option-ref options 'documentation #f)))
  (define (enter? name stat result)
    stat result            ;ignore
    ;; Skip version control directories if any.
    (not (member (basename name) '(".git" ".svn" "CVS"))))

  (define (leaf name stat result)
    stat result                         ;ignore
    (when (string-suffix? ".scm" name)
      (let* ((base-file-name (basename name ".scm"))
             (cmd (format #f " ~a --settings ~a --output ~a --documentation ~a"
                          name
                          settings
                          (string-append output "/" base-file-name ".ttl")
                          (string-append documentation "/" base-file-name ".md"))))
        (touch
         (future
          (begin
            (display (format #f "Running ~a" cmd))
            (display "\n")
            (system cmd)))))))

  (define (down name stat result)
    name stat                         ;ignore
    result)

  (define (up name stat result)
    name stat                           ;ignore
    result)

  (define (skip name stat result)
    name stat                           ;ignore
    result)

  ;; Ignore unreadable files/directories but warn the user.
  (define (error name stat errno result)
    stat                                ;ignore
    (format (current-error-port) "warning: ~a: ~a~%"
            name (strerror errno))
    result)

  (file-system-fold enter? leaf down up skip error
                    0                  ;initial counter is zero bytes
                    "./examples"))