users_controller

module Facebooker
  module ControllerExtensions
    module ClassMethods
      def facebooker_service_for_api
        include ControllerExtensions::InstanceMethods
      end
    end

    module InstanceMethods
      def facebooker_errors
        @facebooker_errors || []
      end
      
      def facebook_user_from_token(token)
        return unless token
        begin
          user = ...
        rescue OAuthException => e
          @facebooker_errors << e.message
        end
      end
    end
  end
end

Api::BaseController.class_eval do
  extend Facebooker::ControllerExtensions::ClassMethods
end

class Api::UsersController < Api::BaseController
  include ThoughtfulAppAuth
  resource_controller_for_api
  facebooker_service_for_api

  create.before do
    facebook_user = facebook_user_from_token params[:access_token]
    if facebook_user
      object.facebook_id = facebooker.id
      object.facebook_link = facebooker.link
    end
  end

  create do
    wants.json { render :json => object.to_json(object_serialization_options) }
    failure.wants.json {
      render :json => object_errors.merge(facebooker_errors).to_json, :status => 422
    }
  end

  def object_serialization_options
    {
      :only => [
              # User fields
              :id, :first_name, :last_name, :api_key, :email, :facebook_id,
              # Address fields
               :firstname, :lastname, :address1, :address2, :zipcode, :state_name, :city, :phone, :name],
      :include => {
         :bill_address => {:include => [:country, :state]},
         :ship_address => {:include => [:country, :state]}
      }
    }
  end
end