defmodule StringsAndBinaries do
  def ascii_printable?(char_list) do
    List.ascii_printable?(char_list)
  end

  def custom_ascii_printable?(char_list) do
    # every character in char list must between 32 and 126
    Enum.all?(char_list, &(32 <= &1 and &1 <= 126))
  end

  def anagram?(word1, word2) do
    # An anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once.
    Enum.sort(String.to_charlist(word1)) == Enum.sort(String.to_charlist(word2))
  end

  def calculate(expression) do
    # this might be a bit dirty, but it solves the issue.
    [a, operator, b] = ~w[ #{expression} ]
    a = String.to_integer(a)
    b = String.to_integer(b)

    case operator do
      "+" -> add(a, b)
      "-" -> substract(a, b)
      "*" -> multiply(a, b)
      "/" -> divide(a, b)
    end
  end

  defp add(a, b), do: a + b
  defp substract(a, b), do: a - b
  defp multiply(a, b), do: a * b
  defp divide(a, b), do: a / b

  def center(dqs_list) do
    longest = Enum.max_by(dqs_list, &String.length/1)
    Enum.map(dqs_list, &print_centered_string(&1, longest))
  end

  defp print_centered_string(dqs, center_string) do
    offset = (String.length(center_string) - String.length(dqs)) / 2
    max_length = round(String.length(dqs) + Float.floor(offset))
    dqs_padding = String.pad_leading(dqs, max_length)
    IO.puts(dqs_padding)
  end
end