(ns day1
  (:require [clojure.string :as string]
            [helpers :refer [get-input]]))

(def test-input "L68
L30
R48
L5
R60
L55
L1
L99
R14
L82
")

(defn- parse-line [l]
  [(first l) (Integer/parseInt (apply str (rest l)))])
  
(defn- parse-input [i]
  (->> (string/split-lines i)
       (map parse-line)))

(defn- rotate [values [direction step]]
  (let [value (peek values)]
    (conj
     values
     (if (= direction \R)
       (rem (+ value step) 100)
       (let [value (- value (rem step 100))]
         (if (neg? value)
           (- 100 (rem (- value) 100))
           value))))))

;(def input (parse-input test-input))
(def input (parse-input (get-input 1)))

(def dial (reduce rotate [50] input))

(println "Password:" (count (filterv zero? dial)))

(def rotations (partition 2 (interleave dial input)))

(defn- count-zeros [[a [direction step]]]
  (cond
    (= direction \R)
    (quot (+ a step) 100)
    (= direction \L)
    (if (>= step a)
      (let [r (inc (abs (quot (- a step) 100)))]
        (if (zero? a) (dec r) r))
      0)))

(println "Password method 0x434C49434B:" (apply + (map count-zeros rotations)))