# = Action Pack Passkey Challenges Controller
#
# Generates fresh WebAuthn challenges for passkey ceremonies. The companion
# JavaScript calls this endpoint before initiating a registration or
# authentication ceremony so that the challenge is issued just-in-time rather
# than embedded in the initial page load.
#
# The generated challenge is returned in the JSON response body. The challenge
# is a signed, expiring token that the server can verify on the subsequent
# form submission without needing server-side state — the challenge is
# extracted from the authenticator's +clientDataJSON+ response.
#
# == Route
#
# By default mounted at +/rails/action_pack/passkey/challenge+ (configurable
# via +config.action_pack.passkey.routes_prefix+).
#
class ActionPack::Passkey::ChallengesController < ActionController::Base
  include ActionPack::Passkey::Request

  # Generates a fresh challenge and returns it as JSON.
  def create
    render json: { challenge: create_passkey_challenge }
  end

  private
    def create_passkey_challenge
      ActionPack::WebAuthn::PublicKeyCredential::Options.new(
        challenge_expiration: Rails.configuration.action_pack.web_authn.request_challenge_expiration
      ).challenge
    end
end