adventofcode/2022/10/part1.js

import * as R from "remeda";

import { readFile } from "../05/part1.js";

const readInput = (...args) =>
  R.pipe(
    readFile(...args),
    (lines) => lines.split("\n"),
    R.compact, // remove last line
    R.map((line) => line.split(" ").map((v, i) => (i ? parseInt(v) : v)))
  );

export const puzzleInput = readInput(import.meta.url, "input");
export const sample = readInput(import.meta.url, "sample");
export const sample2 = readInput(import.meta.url, "sample.2");

export const comsys = () => {
  let cycle = 1;
  let register = 1;
  const scheduled = [];

  return (instr) => {
    if (instr && instr[0] === "addx") {
      scheduled.push(0, instr[1]);
    } else if (instr) {
      scheduled.push(0);
    }
    cycle++;
    register += scheduled.shift() ?? 0;
    return { cycle, register };
  };
};

export const gatherStrength = () => {
  let strength = 0;
  return ({ cycle, signal, register }) => {
    if ((cycle - 20) % 40 === 0) {
      strength += signal;
    }
    return { strength, cycle, signal, register };
  };
};

export const addSignal = (input) => ({
  ...input,
  signal: input.cycle * input.register,
});

export default (instructions) => {
  const sys = comsys();

  instructions = [...instructions];

  return R.pipe(
    R.range(0, 220),
    R.map(() => sys(instructions.shift())),
    R.map(addSignal),
    R.map(gatherStrength()),
    R.last,
    R.prop("strength")
  );
};