defmodule Ketbin.Pastes.Utils do
  defp rand_vowel do
    String.graphemes("aeiou")
    |> Enum.take_random(1)
    |> Enum.at(0)
  end

  defp rand_consonant do
    String.graphemes("bcdfghjklmnpqrstvwxyz")
    |> Enum.take_random(1)
    |> Enum.at(0)
  end

  def generate_key(length \\ 10) do
    random = Enum.random([0, 1])
    Enum.map(0..length, fn i -> if Integer.mod(i, 2) == random, do: rand_consonant(), else: rand_vowel() end)
    |> List.to_string
  end

  def is_url?(url) do
    try do
      uri = URI.parse(url)
      uri.scheme != nil && uri.host =~ "." && Enum.member?(["https", "http", "mailto"], uri.scheme) && !(uri.host =~ "katb.in")
    rescue
      FunctionClauseError -> false
    end
  end

  def is_valid_name?(name) do
    case name do
      x when x in ["pastes", "users"] -> false
      _ -> Regex.match?(~r/^[a-zA-Z0-9_]*$/, name)
    end
  end
end