#!/usr/bin/guile \
-s
!#
(use-modules (ice-9 popen)
             (logging logger)
             (logging port-log)
             (ice-9 ftw)
             (ice-9 match)
             (oop goops)
             (term ansi-color))

(define (expand-file f)
  ;; https://irreal.org/blog/?p=83
  (cond ((absolute-file-name? f) f)
        ((string=? (substring f 0 2) "~/")
         (let ((prefix (passwd:dir (getpwuid (geteuid)))))
           (string-append prefix (substring f 1 (string-length f)))))
        ((char=? (string-ref f 0) #\~)
         (let* ((user-end (string-index f #\/))
                (user (substring f 1 user-end))
                (prefix (passwd:dir (getpwnam user))))
           (string-append prefix (substring f user-end (string-length f)))))
        (else (string-append (getcwd) "/" f))))

(define (symlink? path)
  (false-if-exception
   (eq? 'symlink (stat:type (lstat path)))))

(define (clean-file full-dest)
  (when (false-if-exception (lstat full-dest))
    (display (string-append "\nDeleting previous file: " full-dest))
    ;(delete-file full-dest)
    ))

(define (config-links src target)
  (let ((src-path (expand-file src))
        (target-path (expand-file target)))
    (unless (and (symlink? target-path) (equal? (readlink target-path) src-path))
      (clean-file target-path)
      ;(symlink src-path target-path)
      (display (string-append "\n  Symlink: " src " -> " target)))))

(define (total-file-size file-name target-path)
  "Return the size in bytes of the files under FILE-NAME (similar
          to `du --apparent-size' with GNU Coreutils.)"
  (define src-len (string-length file-name))

  (define (enter? name stat result)
    ;; Skip version control directories.
    (let* ((subdir (substring name src-len))
           (target-subdir (string-append target-path subdir)))
      (format #t "~%~a: ~a | ~a ~a" name subdir target-subdir (stat:type stat))
      (false-if-exception (eq? 'directory (stat:type (lstat target-subdir))))
      ))

  (define (leaf name stat result)
    ;; Return RESULT plus the size of the file at NAME.
    (let* ((subfile (substring name src-len))
           (target-subfile (string-append target-path subfile)))
      (config-links name target-subfile))

    (set-car! result (1+ (car result)))
    result)

  ;; Count zero bytes for directories.
  (define (down name stat result)
    (format #t "~% down on ~a" name)
    (cons 0 result))
  (define (up name stat result)
    (let* ((subdir (substring name src-len))
           (target-subdir (string-append target-path subdir))
           (target-subdir-file-count (length (scandir target-subdir
                                                      (lambda (x)
                                                        (not (member x (list "." ".."))))))))
      (format #t "~% up on ~a ~a ~a ~a " result name target-subdir target-subdir-file-count)
      (when (= (car result) target-subdir-file-count)
        ;(format #t "~% Clear ~a because is identical to source" name)
        (leaf name stat result)))

    (list-set! result 1 (1+ (cadr result)))
    (cdr result))
  ;; Likewise for skipped directories.
  (define skip leaf)

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

  (file-system-fold enter? leaf down up skip error
                    (list 0)
                    file-name))


(total-file-size "config" "/home/titan/.config")

(let ((di "/home/titan/.config/you"))
  (false-if-exception (eq? 'directory (stat:type (lstat di)))))

(error "hci" #f)