unless Fog.mocking?

  module Fog
    module AWS
      class EC2

        # Attach an Amazon EBS volume with a running instance, exposing as specified device
        #
        # ==== Parameters
        # * instance_id<~String> - Id of instance to associate volume with
        # * volume_id<~String> - Id of amazon EBS volume to associate with instance
        # * device<~String> - Specifies how the device is exposed to the instance (e.g. "/dev/sdh")
        #
        # ==== Returns
        # * response<~Fog::AWS::Response>:
        #   * body<~Hash>:
        #     * 'attachTime'<~Time> - Time of attachment was initiated at
        #     * 'device'<~String> - Device as it is exposed to the instance
        #     * 'instanceId'<~String> - Id of instance for volume
        #     * 'requestId'<~String> - Id of request
        #     * 'status'<~String> - Status of volume
        #     * 'volumeId'<~String> - Reference to volume
        def attach_volume(instance_id, volume_id, device)
          request({
            'Action' => 'AttachVolume',
            'VolumeId' => volume_id,
            'InstanceId' => instance_id,
            'Device' => device
          }, Fog::Parsers::AWS::EC2::AttachVolume.new)
        end

      end
    end
  end

else

  module Fog
    module AWS
      class EC2

        def attach_volume(instance_id, volume_id, device)
          response = Fog::Response.new
          response.status = 200
          instance = Fog::AWS::EC2.data[:instances][instance_id]
          volume = Fog::AWS::EC2.data[:volumes][volume_id]
          if instance && volume
            data = {
              'attachTime'  => Time.now,
              'device'      => device,
              'instanceId'  => instance_id,
              'status'      => 'attaching',
              'volumeId'    => volume_id
            }
            volume['attachmentSet'] << data
            response.status = 200
            response.body = {
              'requestId' => Fog::AWS::Mock.request_id
            }.merge!(data)
          else
            response.status = 400
            raise(Fog::Errors.status_error(200, 400, response))
          end
          response
        end

      end
    end
  end

end