swiss

defmodule Swiss.String do
  @moduledoc """

  A few extra functions to deal with Strings. Heavily inspired by lodash.

  """

  @word_regex ~r/[^\x00-\x2f\x3a-\x40\x5b-\x60\x7b-\x7f]+/
  @upper_word_regex ~r/(^[A-Z]+$)|[A-Z][a-z0-9]*/

  @doc """

  Deburrs a string from unicode to its ascii equivalent.



  ## Examples

      iex> Swiss.String.deburr "hola señor!"

      "hola senor!"

  """
  @spec deburr(String.t) :: String.t
  def deburr(string) do
    string
    |> :unicode.characters_to_nfd_binary()
    |> String.replace(~r/[^\x00-\x7F]/u, "")
  end

  @doc """

  Decomposes a string into an array of its words.



  ## Examples

      iex> Swiss.String.words "FredBarney"

      ["Fred", "Barney"]

      iex> Swiss.String.words "fred, barney, & pebbles"

      ["fred", "barney", "pebbles"]

      iex> Swiss.String.words "fred, barney, & pebbles", ~r/[^, ]+/

      ["fred", "barney", "&", "pebbles"]

  """
  @spec words(String.t, Regex.t) :: [String.t]
  def words(string, pattern \\ @word_regex) do
    string
    |> String.split(pattern, trim: true, include_captures: true)
    |> Enum.filter(&String.match?(&1, pattern))
    |> Enum.flat_map(&String.split(&1, @upper_word_regex, trim: true, include_captures: true))
  end

  @doc """

  Converts a string into kebab-case.



  ## Examples

      iex> Swiss.String.kebab_case "Foo Bar"

      "foo-bar"

      iex> Swiss.String.kebab_case "--foo-bar--"

      "foo-bar"

      iex> Swiss.String.kebab_case "__FOO_BAR__"

      "foo-bar"

      iex> Swiss.String.kebab_case "FooBar"

      "foo-bar"

  """
  @spec kebab_case(String.t) :: String.t
  def kebab_case(string) do
    string
    |> deburr()
    |> words()
    |> Enum.map(&String.downcase/1)
    |> Enum.join("-")
  end

  @doc """

  Converts a string into snake_case.



  ## Examples

      iex> Swiss.String.snake_case "Foo Bar"

      "foo_bar"

      iex> Swiss.String.snake_case "--foo-bar--"

      "foo_bar"

      iex> Swiss.String.snake_case "__FOO_BAR__"

      "foo_bar"

  """
  @spec snake_case(String.t) :: String.t
  def snake_case(string) do
    string
    |> deburr()
    |> String.downcase()
    |> words()
    |> Enum.join("_")
  end
end