#!/usr/bin/guile
!#

(import (sph) (sph alist) (sph rate) (sph cli) (sph filesystem) (sph string))

(define program-description
  "this program changes the rating of files relative to their current one.
  direction can be \"up\" or \"down\".
  a rating is designated by a numeric directory in the path unequal to the current path.
  see the \"rate\" program for more information")

(define command-line-interface
  (cli-create #:description program-description #:options (q (((direction difference path ...) #f)))))

(define (rate-modify-cli)
  (let (options (command-line-interface))
    (alist-bind options (direction difference path)
      (each
        (let (difference (* (if (string-equal? "up" direction) -1 1) (string->number difference)))
          (l (path)
            (and-let*
              ( (current-rating (rate-path->rating (realpath* path)))
                (new-rating (max 0 (+ current-rating difference))))
              (if (not (equal? current-rating new-rating)) (rate new-rating path)))))
        path))))

(rate-modify-cli)