;;; -*- lexical-binding: t -*-
;;
;; this file:
;;   https://dataswamp.org/~incal/terror-3/ev3-control-cli.el

(require 'cl-lib)
(require 'ev3-motor-rotate)
(require 'ev3-motor-stop)

(defun str-to-int (str)
  (if (string= str "0")
      0
    (let ((res (string-to-number str)))
      (unless (zerop res) ; this is so "" will return nil, not 0
        (round res)) )))

(defun ev3-display-help ()
  (find-file (concat default-directory "README")) )

(defun ev3-cmd-loop ()
  (interactive)
  (cl-loop
   (let*((ps    "[terror-3] ")
         (cmd   (read-from-minibuffer ps))
         (speed (str-to-int cmd)) )
     (if speed
         (set-motor-both speed)
       (pcase cmd
         ((or "" "help" "h")       (progn
                                     (ev3-display-help)
                                     (cl-return) ))
         ((or "quit" "q")          (cl-return))
         ((or "rotate left"  "rl") (ev3-rotate-left))
         ((or "rotate right" "rr") (ev3-rotate-right))
         ((or "stop" "s")          (ev3-stop))
         (_                        (message "DNC (hit `h' for help)") ))))))

(provide 'ev3-control-cli)