/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * vim: sw=2 ts=8 et :
 */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

include LayersSurfaces;
include LayersMessages;
include protocol PCompositorBridge;
include protocol PTexture;

include "mozilla/GfxMessageUtils.h";
include "mozilla/layers/LayersMessageUtils.h";

using struct mozilla::layers::TextureInfo from "mozilla/layers/CompositorTypes.h";
using struct mozilla::void_t from "mozilla/ipc/IPCCore.h";
using struct mozilla::null_t from "mozilla/ipc/IPCCore.h";
using class mozilla::layers::APZTestData from "mozilla/layers/APZTestData.h";
using mozilla::layers::FrameUniformityData from "mozilla/layers/FrameUniformityData.h";
using mozilla::layers::ScrollableLayerGuid from "mozilla/layers/ScrollableLayerGuid.h";
using mozilla::layers::ScrollableLayerGuid::ViewID from "mozilla/layers/ScrollableLayerGuid.h";
using struct mozilla::layers::TextureFactoryIdentifier from "mozilla/layers/CompositorTypes.h";
using mozilla::layers::LayersBackend from "mozilla/layers/LayersTypes.h";
using mozilla::layers::LayerHandle from "mozilla/layers/LayersTypes.h";
using mozilla::layers::CompositableHandle from "mozilla/layers/LayersTypes.h";
using mozilla::layers::LayersObserverEpoch from "mozilla/layers/LayersTypes.h";
using mozilla::layers::TransactionId from "mozilla/layers/LayersTypes.h";

/**
 * The layers protocol is spoken between thread contexts that manage
 * layer (sub)trees.  The protocol comprises atomically publishing
 * layer subtrees to a "shadow" thread context (which grafts the
 * subtree into its own tree), and atomically updating a published
 * subtree.  ("Atomic" in this sense is wrt painting.)
 */

namespace mozilla {
namespace layers {

/**
 * The PLayerTransaction protocol manages the layer tree for a single "browser".
 * The "browser" can be a top-level browser window, in which case the PLayer-
 * TransactionChild exists in the UI process. The "browser" can also be a content
 * tab, in which case the PLayerTransactionChild exists in the content process.
 * In either case, the PLayerTransactionParent exists in the GPU process (if
 * there is one) or the UI process otherwise.
 */
sync protocol PLayerTransaction {
  manager PCompositorBridge;

parent:
  // The isFirstPaint flag can be used to indicate that this is the first update
  // for a particular document.
  async Update(TransactionInfo txn);

  async PaintTime(TransactionId id, TimeDuration paintTime);

  async SetLayersObserverEpoch(LayersObserverEpoch aChildEpoch);

  // Create a new Compositable.
  async NewCompositable(CompositableHandle handle, TextureInfo info);

  // Release an object that is no longer in use.
  async ReleaseLayer(LayerHandle layer);
  async ReleaseCompositable(CompositableHandle compositable);

  // Tell the compositor to notify APZ that a layer has been confirmed for an
  // input event.
  async SetConfirmedTargetAPZC(uint64_t aInputBlockId, ScrollableLayerGuid[] aTargets);

  // Testing APIs

  // Enter test mode, set the sample time to sampleTime, and resample
  // animations. sampleTime must not be null.
  sync SetTestSampleTime(TimeStamp sampleTime);
  // Leave test mode and resume normal compositing
  sync LeaveTestMode();

  // Returns |OMTAValue| applied to the layer.
  sync GetAnimationValue(uint64_t aCompositorAnimationId) returns (OMTAValue value);

  // Returns the value of the transform applied to the layer by animation and
  // APZC.
  sync GetTransform(LayerHandle layer) returns (Matrix4x4? transform);

  // The next time the layer tree is composited, add this async scroll offset in
  // CSS pixels for the given ViewID.
  // Useful for testing rendering of async scrolling.
  sync SetAsyncScrollOffset(ViewID id, float x, float y);

  // The next time the layer tree is composited, include this async zoom in
  // for the given ViewID.
  // Useful for testing rendering of async zooming.
  sync SetAsyncZoom(ViewID id, float zoom);

  // Flush any pending APZ repaints to the main thread.
  async FlushApzRepaints();

  // Drop any front buffers that might be retained on the compositor
  // side.
  async ClearCachedResources();

  // Schedule a composite if one isn't already scheduled.
  async ScheduleComposite();

  // Get a copy of the compositor-side APZ test data instance for this
  // layers id.
  sync GetAPZTestData() returns (APZTestData data);

  // Child requests frame uniformity measurements
  sync GetFrameUniformity() returns (FrameUniformityData data);

  // Query a named property from the last frame
  sync RequestProperty(nsString property) returns (float value);

  // Return the TextureFactoryIdentifier for this compositor.
  sync GetTextureFactoryIdentifier() returns (TextureFactoryIdentifier aIdentifier);

  async RecordPaintTimes(PaintTiming timing);

  async Shutdown();
  sync ShutdownSync();

child:
  async __delete__();
};

} // namespace layers
} // namespace mozilla