Advent of Code 2023 - Day 2 - Elixir

aoc_23_01_v2.ex

defmodule Cube.RegEx do
  @regex_game_number ~r/Game (\d+)/
  @regex_color_thresholds ~r/(1[3-9]|[2-9][0-9]) red|(1[4-9]|[2-9][0-9]) green|(1[5-9]|[2-9][0-9]) blue/

  @spec count(binary()) :: any()
  def count(filename) do
    File.read!(Path.expand(filename))
    |> String.split("\n", trim: true)
    |> Enum.reject(&match_color_thresholds?/1)
    |> Enum.reduce(0, &sum_game_numbers/2)
  end

  defp match_color_thresholds?(game) do
    Regex.match?(@regex_color_thresholds, game)
  end

  defp sum_game_numbers(game, acc) do
    [game_number] = Regex.run(@regex_game_number, game, capture: :all_but_first)
    acc + String.to_integer(game_number)
  end
end