import gleam/int
import gleam/string
import simplifile

/// Read input for a given day. If example is True, reads from dayXX_example.txt
pub fn read_input(day: Int, example: Bool) -> Result(List(String), String) {
  let day_str = int.to_string(day) |> string.pad_start(2, "0")
  let suffix = case example {
    True -> "_example"
    False -> ""
  }
  let path = "input/day" <> day_str <> suffix <> ".txt"

  case simplifile.read(path) {
    Ok(content) ->
      Ok(
        content
        |> string.trim
        |> string.split("\n"),
      )
    Error(e) -> Error("failed to read " <> path <> ": " <> string.inspect(e))
  }
}