defmodule Makeup.Lexers.DiffLexer.Helper do
  @moduledoc false

  import NimbleParsec
  import Makeup.Lexer.Combinators

  def line_starting_with(start, token_type) when is_binary(start) do
    string(start)
    |> rest_of_line()
    |> token(token_type)
  end

  def line_starting_with([_, _ | _] = start, token_type) do
    start
    |> Enum.map(&string/1)
    |> choice()
    |> rest_of_line()
    |> token(token_type)
  end

  def text_line() do
    rest_of_line() |> token(:text)
  end

  defp rest_of_line(combinator \\ empty()) do
    utf8_string(combinator, [not: ?\n, not: ?\r], min: 0)
  end

  def newline(combinator \\ empty()) do
    concat(combinator, ascii_string([?\n, ?\r], min: 1) |> token(:whitespace))
  end
end