module Enki
  class DeletePageUndo < UndoItem
    def process!
      raise('Page already exists') if Page.find_by_id(loaded_data.delete('id').to_i)

      page = nil
      transaction do
        page = Page.create!(loaded_data)
        self.destroy
      end
      page
    end

    def loaded_data
      @loaded_data ||= YAML.load(data)
    end

    def description
      "Deleted page '#{loaded_data['title']}'"
    end

    def complete_description
      "Recreated page '#{loaded_data['title']}'"
    end

    class << self
      def create_undo(page)
        DeletePageUndo.create!(:data => page.attributes.to_yaml)
      end
    end
  end
end