18F/identity-idp

# frozen_string_literal: true

class AuthMethodsSession
  attr_reader :user_session

  MAX_AUTH_EVENTS = 10

  def initialize(user_session:)
    @user_session = user_session
  end

  def authenticate!(auth_method)
    user_session[TwoFactorAuthenticatable::NEED_AUTHENTICATION] = false
    user_session[:auth_events] = auth_events.
      push({ auth_method:, at: Time.zone.now }).
      last(MAX_AUTH_EVENTS)
  end

  def auth_events
    user_session[:auth_events] || []
  end

  def last_auth_event
    auth_events.last
  end

  def last_2fa_auth_event
    auth_events.reverse.find do |auth_event|
      auth_event[:auth_method] != TwoFactorAuthenticatable::AuthMethod::REMEMBER_DEVICE
    end
  end

  def reauthenticate_at
    last_2fa_auth_event_at = last_2fa_auth_event&.[](:at)
    if last_2fa_auth_event_at
      last_2fa_auth_event_at.to_datetime + reauthn_window
    else
      Time.zone.now
    end
  end

  def recently_authenticated_2fa?
    reauthenticate_at.future?
  end

  private

  def reauthn_window
    IdentityConfig.store.reauthn_window.seconds
  end
end