fcc_discord_challenge_2.clj

#!/usr/bin/env bb
(ns c2
  (:require [babashka.fs :as fs]))

(def start (first *command-line-args*))

(defn line-prefix [levels]
  (apply str
         (for [[global-level written] (map-indexed vector levels)
               :let [global-level (inc global-level)
                     current-level? (= global-level (count levels))]]
           (if (= 0 written)
             (if current-level?
               "└── "
               "     ")
             (if current-level?
               "├── "
               "│    ")))))

(defn print-tree [dir]
  (loop [[child & more] (.listFiles dir)
         levels [(inc (count more))]]
    (when-not (nil? child)
      (let [level (- (count (fs/components child))
                     (count (fs/components dir)))
            levels (subvec levels 0 level)
            levels (update levels (dec level) (fnil dec 1))
            children (.listFiles child)
            prefix (line-prefix levels)]
        (println (str prefix (-> child fs/absolutize fs/normalize)))
        (recur (apply conj more children)
               (conj levels (count children)))))))

(print-tree (fs/file start))