class Champs::PhoneChamp < Champs::TextChamp
  # We want to allow:
  # * international (e164) phone numbers
  # * “french format” (ten digits with a leading 0)
  # * DROM numbers
  #
  # However, we need to special-case some ten-digit numbers,
  # because the ARCEP assigns some blocks of "O6 XX XX XX XX" numbers to DROM operators.
  # Guadeloupe          | GP | +590 | 0690XXXXXX, 0691XXXXXX
  # Guyane              | GF | +594 | 0694XXXXXX
  # Martinique          | MQ | +596 | 0696XXXXXX, 0697XXXXXX
  # Réunion             | RE | +262 | 0692XXXXXX, 0693XXXXXX
  # Mayotte             | YT | +262 | 0692XXXXXX, 0693XXXXXX
  # Nouvelle-Calédonie  | NC | +687 |
  # Polynésie française | PF | +689 | 40XXXXXX, 45XXXXXX, 87XXXXXX, 88XXXXXX, 89XXXXXX
  #
  # Cf: Plan national de numérotation téléphonique,
  # https://www.arcep.fr/uploads/tx_gsavis/05-1085.pdf  “Numéros mobiles à 10 chiffres”, page 6
  #
  # See issue #6996.
  DEFAULT_COUNTRY_CODES = [:FR, :GP, :GF, :MQ, :RE, :YT, :NC, :PF].freeze

  validates :value,
    phone: {
      possible: true,
      allow_blank: true,
      message: I18n.t(:not_a_phone, scope: 'activerecord.errors.messages')
    }, unless: -> { Phonelib.valid_for_countries?(value, DEFAULT_COUNTRY_CODES) }

  def to_s
    return '' if value.blank?

    if Phonelib.valid_for_countries?(value, DEFAULT_COUNTRY_CODES)
      Phonelib.parse_for_countries(value, DEFAULT_COUNTRY_CODES).full_national
    else
      # When he phone number is possible for the default countries, but not strictly valid,
      # `full_national` could mess up the formatting. In this case just return the original.
      value
    end
  end
end