module Joint
  class AttachmentProxy
    def initialize(instance, name)
      @instance, @name = instance, name
    end

    def id
      @instance.send("#{@name}_id")
    end

    def name
      @instance.send("#{@name}_name")
    end

    def size
      @instance.send("#{@name}_size")
    end

    def type
      @instance.send("#{@name}_type")
    end

    def nil?
      !@instance.send("#{@name}?")
    end

    def grid_io
      @grid_io ||= @instance.grid.get(id)
    end

    def method_missing(method, *args, &block)
      grid_io.send(method, *args, &block)
    end
  end
end