defmodule CLDRex.Calendar do
  @moduledoc """

  """
  alias CLDRex.Main
  import CLDRex.Utils

  @doc """
  Provide a map of months in the locale localized based on desired context and
  format.

  Accepted options are:

    - calendar: the calendar to use. default: `:gregorian`
    - context: the calendar information you wish to get. default: `:format`. commonly available:
        - `:format`
        - `:"stand-alone"`
    - format: the data format for the months. default: `:wide`. commonly available:
        - `:wide`
        - `:short`
        - `:narrow`
        - `:abbreviated`

  ## Examples

    iex> CLDRex.Calendar.months(:en)
    %{"1": 'January', "10": 'October', "11": 'November', "12": 'December',
      "2": 'February', "3": 'March', "4": 'April', "5": 'May', "6": 'June',
      "7": 'July', "8": 'August', "9": 'September'}

    iex> CLDRex.Calendar.months(:en, context: :"stand-alone", format: :narrow)
    %{"1": 'J', "10": 'O', "11": 'N', "12": 'D', "2": 'F', "3": 'M', "4": 'A',
      "5": 'M', "6": 'J', "7": 'J', "8": 'A', "9": 'S'}

  """
  @spec months(atom) :: list
  def months(locale, options \\ %{}) do
    locale = normalize_locale(locale)
    fallback = fallback(locale)
    cal = get_in(options, [:calendar]) || :gregorian
    ctxt = get_in(options, [:context]) || :format
    fmt = get_in(options, [:format]) || :wide

    m = get_in(Main.cldr_main_data, [locale, :calendar, cal, ctxt, fmt])

    if !m || Enum.empty?(m),
      do: m = get_in(Main.cldr_main_data, [fallback, :calendar, cal, ctxt, fmt])

    m
  end
end