const sample = await Deno.readTextFile("sample.txt");
const input = await Deno.readTextFile("input.txt");

const solvePart1 = (data: string): number | undefined =>
  data
    .split("\n")
    .filter(Boolean)
    .map(parseFloat)
    .reduce(
      ([count, lastValue], value, index) => [
        count + (index > 0 && value > lastValue ? 1 : 0),
        value,
      ],
      [0, 0]
    )
    .shift();

console.log("Sample:", solvePart1(sample));
console.log("Input", solvePart1(input));

const solvePart2 = (data: string): number | undefined =>
  data
    .split("\n")
    .filter(Boolean)
    .map(parseFloat)
    .reduce(
      (windows, _, index, values) =>
        index >= values.length - 2
          ? windows
          : [...windows, values[index] + values[index + 1] + values[index + 2]],
      [] as number[]
    )
    .reduce(
      ([count, lastValue], value, index) => [
        count + (index > 0 && value > lastValue ? 1 : 0),
        value,
      ],
      [0, 0]
    )
    .shift();

console.log("Sample:", solvePart2(sample));
console.log("Input", solvePart2(input));