Day 18

Mix.install([
  {:kino, "~> 0.7.0"}
])

IEx.Helpers.c("/Users/johnb/dev/2023adventOfCode/advent_of_code.ex")
alias AdventOfCode, as: AOC
alias Kino.Input

# Note: when making the next template, something like this works well:
#   `cat day04.livemd | sed 's/03/04/' > day04.livemd`
#

Installation and Data

input_p1example = Kino.Input.textarea("Example Data")

input_p1puzzleInput = Kino.Input.textarea("Puzzle Input")

input_source_select =
  Kino.Input.select("Source", [{:example, "example"}, {:puzzle_input, "puzzle input"}])

p1data = fn ->
  (Kino.Input.read(input_source_select) == :example &&
     Kino.Input.read(input_p1example)) ||
    Kino.Input.read(input_p1puzzleInput)
end

Part 1

defmodule Day18 do
  @grid_width 10_000
  @start 500

  def solve(text) do
    plan =
      AOC.as_single_lines(text)
      |> Enum.reduce([], fn line, acc ->
        [dir, dist, color] = String.split(line, " ", trim: true)
        [%{dir: dir, dist: String.to_integer(dist), color: color} | acc]
      end)
      |> Enum.reverse()

    steps =
      plan
      |> Enum.reduce(
        [%{x: @start, y: @start, color: "(#ffffff)"}],
        fn %{dir: dir, dist: dist, color: color}, [%{x: x, y: y} | _rest] = acc ->
          {x2, y2} =
            case dir do
              "U" -> {x, y - @grid_width * dist}
              "D" -> {x, y + @grid_width * dist}
              "L" -> {x - dist, y}
              "R" -> {x + dist, y}
            end

          [%{x: x2, y: y2, color: color} | acc]
        end
      )

    extents =
      steps
      |> Enum.reduce(
        %{xmin: @start, xmax: @start, ymin: @start, ymax: @start},
        fn %{x: x2, y: y2}, %{xmin: xmin, xmax: xmax, ymin: ymin, ymax: ymax} ->
          %{xmin: min(xmin, x2), xmax: max(xmax, x2), ymin: min(ymin, y2), ymax: max(ymax, y2)}
        end
      )

    real_y = fn y -> (y - @start) / @grid_width end
    IO.inspect([extents, real_y.(extents.ymin), real_y.(extents.ymax)])
  end

  def solve2(text) do
    text
  end
end

p1data.()
|> Day18.solve()
|> IO.inspect(label: "\n*** Part 1 solution (example: 62)")

#

# p1data.()
# |> Day18.solve2()
# |> IO.inspect(label: "\n*** Part 2 solution (example: )")

#