#!/usr/bin/guile
!#

;arguments: integer
;displays a list of numbers in the golden-ratio above and below the input number
(import (sph) (sph math) (sph number))

(define* (golden-ratios start-number #:optional (count 10))
  (let loop
    ( (counter count) (increasing (list (* start-number golden-ratio)))
      (decreasing (list (/ start-number golden-ratio))))
    (if (> counter 0)
      (loop (- counter 1) (pair (* (first increasing) golden-ratio) increasing)
        (pair (/ (first decreasing) golden-ratio) decreasing))
      (pair increasing (reverse decreasing)))))

(define (display-number-list a)
  (each (l (e) (display (round-to-decimal-places e 3)) (display " ") (display-line e)) a))

(define (golden-ratios-cli arguments)
  (if (null? arguments) (display-line "missing 1 integer argument")
    (let (numbers (golden-ratios (string->number (first (tail (program-arguments))))))
      (display-number-list (first numbers)) (newline) (display-number-list (tail numbers)))))

(golden-ratios-cli (tail (program-arguments)))