// Copyright (c) 2010 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//
// Protocol for communication between chromoting client and host.

syntax = "proto2";

option optimize_for = LITE_RUNTIME;

package remoting;

// A message that gets sent to the client after the client is connected to the
// host. It contains information that the client needs to know about the host.
// NEXT ID: 3
message InitClientMessage {
  required int32 width = 1;
  required int32 height = 2;
}

// A message to denote the beginning of an update stream. It will be followed
// by 0 or more PartialUpdateStream messages and then a EndUpdateStream message.
// NEXT ID: 1
message BeginUpdateStreamMessage {
}

// A message to denote the end of an update stream.
// NEXT ID: 1
message EndUpdateStreamMessage {
}

// Identifies how the image was encoded.
enum UpdateStreamEncoding {
  EncodingNone = 0;
  EncodingZlib = 1;
}

// Identifies the pixel format.
// Note that this list should match exactly the same as
// media::VideoFrame::Format in media/base/video_frame.h.
enum PixelFormat {
  PixelFormatInvalid = 0;
  PixelFormatRgb555 = 1;
  PixelFormatRgb565 = 2;
  PixelFormatRgb24 = 3;
  PixelFormatRgb32 = 4;
  PixelFormatRgba = 5;
  PixelFormatYv12 = 6;
  PixelFormatYv16 = 7;
  PixelFormatEmpty = 8;
  PixelFormatAscii = 9;
}

// A message with info about the update stream.
// NEXT ID: 6
message UpdateStreamPacketHeader {
  // X,Y coordinates (in screen pixels) for origin of this update.
  required int32 x = 1;
  required int32 y = 2;

  // Width, height (in screen pixels) for this update.
  required int32 width = 3;
  required int32 height = 4;

  // The encoding used for this image update.
  optional UpdateStreamEncoding encoding = 5 [default=EncodingNone];

  // The pixel format of this image.
  optional PixelFormat pixel_format = 6 [default=PixelFormatRgb24];
}

// A message to denote a partial update stream.
// NEXT ID: 3
message UpdateStreamPacketMessage {
  // TODO(garykac): Make this required and fix unit tests.
  optional UpdateStreamPacketHeader header = 2;
  optional bytes data = 1;
}

// Defines the message that is sent from the host to the client.
// Only one of these messages should be present.
// NEXT ID: 5
message HostMessage {
  optional InitClientMessage init_client= 1;
  optional BeginUpdateStreamMessage begin_update_stream = 2;
  optional EndUpdateStreamMessage end_update_stream = 3;
  optional UpdateStreamPacketMessage update_stream_packet = 4;
}

// Defines a keyboard event.
// NEXT ID: 3
message KeyEvent {
  // The POSIX key code.
  required int32 key = 1;
  required bool pressed = 2;
}

// Sets the position of the mouse cursor.
// The coordinate value is between [0 .. 1] which is relative to the
// dimension of the screen area.
// NEXT ID: 3
message MouseSetPositionEvent {
  required float x = 1;
  required float y = 2;
}

// Adjust the position of the mouse cursor by an offset.
// NEXT ID: 3
message MouseMoveEvent {
  required int32 offset_x = 1;
  required int32 offset_y = 2;
}

// Motion of the mouse wheel.
// NEXT ID: 3
message MouseWheelEvent {
  required int32 offset_x = 1;
  required int32 offset_y = 2;
}

// Mouse button is pressed down.
// NEXT ID: 2
message MouseDownEvent {
  enum Button {
    LEFT = 0;
    MIDDLE = 1;
    RIGHT = 2;
  }
  required Button button = 1;
}

// Mouse button is released.
// NEXT ID: 2
message MouseUpEvent {
  enum Button {
    LEFT = 0;
    MIDDLE = 1;
    RIGHT = 2;
  }
  required Button button = 1;
}

// Defines the message that is sent from the client to the host.
// Only one of these messages should be present.
// NEXT ID: 7
message ClientMessage {
  optional KeyEvent key_event = 1;
  optional MouseSetPositionEvent mouse_set_position_event = 2;
  optional MouseMoveEvent mouse_move_event = 3;
  optional MouseWheelEvent mouse_wheel_event = 4;
  optional MouseDownEvent mouse_down_event = 5;
  optional MouseUpEvent mouse_up_event = 6;
}