(ns adventofcode2019.day06
    [:require [adventofcode2019.lib :refer :all]
              [clojure.string :as str]])

;; FIXME: is the input guaranteed in-order?
(defn a-orbits-b [orbits-map [b a]]
  (if (contains? orbits-map b)
    (-> (assoc orbits-map a {:parent b, :children [], :depth (inc (:depth b))})
        (update-in [b :children] conj a))
    (-> (assoc orbits-map b {:parent nil, :children [], :depth 0})
        (a-orbits-b [b a]))))

(defn day06 []
  (let [input (map #(str/split % #")") (get-list-from-file (input-file)))
        orbits-map (reduce a-orbits-b {} input)] 
    (part1 (reduce + (map :depth orbits-map)))
    #_(part2)))