(ns aoc.core
  [:require [clojure.string :as str]])

(def get-list-from-file
  #(str/split #"," (slurp %)))

(def parse-int
  #(Integer/parseInt %))

(def opcodes {1 +, 2 *})
(defn perform-operation [[opcode fst snd thd] program]
  (let [opcode-fn (opcodes opcode)
        fst-val (program fst)
        snd-val (program snd)]
    (assoc program thd (opcode-fn fst-val snd-val))))

(defn intcode [program]
  (loop [program program
         counter 0]
    (let [opcode (program counter)]
      (if (= opcode 99)
        program
        (recur (perform-operation (map program (take 4 (iterate inc counter)))
                                  program)
               (+ counter 4))))))

(defn -main []
  (let [input (mapv parse-int (get-list-from-file "input"))
        fixed-input (assoc input 1 12 2 1)] 
    (println (first (intcode fixed-input)))))

(-main)