// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CC_MOJO_EMBEDDER_ASYNC_LAYER_TREE_FRAME_SINK_H_
#define CC_MOJO_EMBEDDER_ASYNC_LAYER_TREE_FRAME_SINK_H_

#include <memory>
#include <string>
#include <variant>
#include <vector>

#include "base/memory/raw_ptr.h"
#include "base/memory/read_only_shared_memory_region.h"
#include "base/memory/weak_ptr.h"
#include "base/task/single_thread_task_runner.h"
#include "base/threading/platform_thread.h"
#include "build/build_config.h"
#include "cc/mojo_embedder/mojo_embedder_export.h"
#include "cc/trees/layer_tree_frame_sink.h"
#include "components/viz/common/frame_sinks/begin_frame_source.h"
#include "components/viz/common/frame_timing_details.h"
#include "components/viz/common/frame_timing_details_map.h"
#include "components/viz/common/surfaces/parent_local_surface_id_allocator.h"
#include "components/viz/common/surfaces/surface_id.h"
#include "gpu/ipc/client/client_shared_image_interface.h"
#include "mojo/public/cpp/bindings/associated_remote.h"
#include "mojo/public/cpp/bindings/direct_receiver.h"
#include "mojo/public/cpp/bindings/pending_associated_remote.h"
#include "mojo/public/cpp/bindings/pending_receiver.h"
#include "mojo/public/cpp/bindings/pending_remote.h"
#include "mojo/public/cpp/bindings/receiver.h"
#include "mojo/public/cpp/bindings/remote.h"
#include "services/viz/public/mojom/compositing/compositor_frame_sink.mojom.h"

namespace viz {
class RasterContextProvider;
}  // namespace viz

namespace cc {

class LayerContext;
class LayerTreeHostImpl;

namespace mojo_embedder {

// A mojo-based implementation of LayerTreeFrameSink. The typically-used
// implementation for cc instances that do not share a process with the viz
// display compositor.
class CC_MOJO_EMBEDDER_EXPORT AsyncLayerTreeFrameSink
    : public LayerTreeFrameSink,
      public viz::mojom::CompositorFrameSinkClient,
      public viz::ExternalBeginFrameSourceClient {
 public:
  struct CC_MOJO_EMBEDDER_EXPORT UnboundMessagePipes {
    UnboundMessagePipes();
    ~UnboundMessagePipes();
    UnboundMessagePipes(UnboundMessagePipes&& other);

    bool HasUnbound() const;

    // Only one of |compositor_frame_sink_remote| or
    // |compositor_frame_sink_associated_remote| should be set.
    mojo::PendingRemote<viz::mojom::CompositorFrameSink>
        compositor_frame_sink_remote;
    mojo::PendingAssociatedRemote<viz::mojom::CompositorFrameSink>
        compositor_frame_sink_associated_remote;
    mojo::PendingReceiver<viz::mojom::CompositorFrameSinkClient>
        client_receiver;
  };

  struct CC_MOJO_EMBEDDER_EXPORT InitParams {
    InitParams();
    ~InitParams();

    scoped_refptr<base::SingleThreadTaskRunner> compositor_task_runner;
    std::unique_ptr<viz::SyntheticBeginFrameSource>
        synthetic_begin_frame_source;
    UnboundMessagePipes pipes;
    bool wants_animate_only_begin_frames = false;
    base::PlatformThreadId io_thread_id = base::kInvalidThreadId;
    base::PlatformThreadId main_thread_id = base::kInvalidThreadId;

    // If `true`, the CompositorFrameSinkClient receiver will receive IPC
    // directly to the thread on which the AsyncLayerTreeFrameSink lives, rather
    // than hopping through the I/O thread first. Only usable if the
    // AsyncLayerTreeFrameSink lives on a thread which uses an IO message pump.
    bool use_direct_client_receiver = false;

    // If |true|, presentation feedback will be used on every begin frame to
    // update the vsync parameters of the |synthetic_begin_frame_source|.
    bool use_begin_frame_presentation_feedback = false;

    // If `true`, SetNeedsBeginFrame(true) IPCs are omitted. Instead, the client
    // relies on unsolicited compositor frame submission to notify the server
    // side to start sending BeginFrame requests.
    //
    // Note: SetNeedsBeginFrame(false) IPCs are sent regardless what value
    // `auto_needs_begin_frame` is.
    bool auto_needs_begin_frame = false;

    // If it has value(n), internal begin frame source will be used when n
    // consecutive "did not produce frame" are observed. It will stop using
    // internal begin frame source when there's a submitted compositor frame.
    // This should be mutually exclusive from synthetic_begin_frame_source.
    // And `auto_needs_begin_frame` will be true if this is set.
    std::optional<int>
        num_did_not_produce_frame_before_internal_begin_frame_source;
  };

  AsyncLayerTreeFrameSink(
      scoped_refptr<viz::RasterContextProvider> context_provider,
      scoped_refptr<viz::RasterContextProvider> worker_context_provider,
      scoped_refptr<gpu::ClientSharedImageInterface> shared_image_interface,
      InitParams* params);

  AsyncLayerTreeFrameSink(const AsyncLayerTreeFrameSink&) = delete;
  ~AsyncLayerTreeFrameSink() override;

  AsyncLayerTreeFrameSink& operator=(const AsyncLayerTreeFrameSink&) = delete;

  const viz::LocalSurfaceId& local_surface_id() const {
    return local_surface_id_;
  }
  float last_submitted_device_scale_factor() const {
    return last_submitted_device_scale_factor_;
  }
  const gfx::Size& last_submitted_size_in_pixels() const {
    return last_submitted_size_in_pixels_;
  }

  bool auto_needs_begin_frame() const { return auto_needs_begin_frame_; }
  bool needs_begin_frames() const { return needs_begin_frames_; }

  // LayerTreeFrameSink implementation.
  bool BindToClient(LayerTreeFrameSinkClient* client) override;
  void DetachFromClient() override;
  void SetLocalSurfaceId(const viz::LocalSurfaceId& local_surface_id) override;
  void SubmitCompositorFrame(viz::CompositorFrame frame,
                             bool hit_test_data_changed) override;
  void DidNotProduceFrame(const viz::BeginFrameAck& ack,
                          FrameSkippedReason reason) override;
  void ExportFrameTiming() override;
  std::unique_ptr<LayerContext> CreateLayerContext(
      LayerTreeHostImpl& host_impl) override;

  const viz::HitTestRegionList& get_last_hit_test_data_for_testing() const {
    return last_hit_test_data_;
  }

  bool use_internal_begin_frame_source_for_testing() const {
    return use_internal_begin_frame_source_;
  }

  void SetTimeSourceOfInternalBeginFrameForTesting(
      std::unique_ptr<viz::DelayBasedTimeSource> source);

 private:
  friend class AsyncLayerTreeFrameSinkSimpleTest;

  // mojom::CompositorFrameSinkClient implementation:
  void DidReceiveCompositorFrameAck(
      std::vector<viz::ReturnedResource> resources) override;
  void OnBeginFrame(const viz::BeginFrameArgs& begin_frame_args,
                    const viz::FrameTimingDetailsMap& timing_details,
                    std::vector<viz::ReturnedResource> resources) override;
  void OnBeginFramePausedChanged(bool paused) override;
  void ReclaimResources(std::vector<viz::ReturnedResource> resources) override;
  void OnCompositorFrameTransitionDirectiveProcessed(
      uint32_t sequence_id) override;
  void OnSurfaceEvicted(const viz::LocalSurfaceId& local_surface_id) override;

  void NotifyNewLocalSurfaceIdExpectedWhilePaused() override;

  // ExternalBeginFrameSourceClient implementation.
  void OnNeedsBeginFrames(bool needs_begin_frames) override;

  void OnMojoConnectionError(uint32_t custom_reason,
                             const std::string& description);

  void UpdateNeedsBeginFramesInternal(bool needs_begin_frames);

  void UpdateInternalBeginFrameSource(bool use_internal_source);

  const bool use_direct_client_receiver_;
  bool begin_frames_paused_ = false;
  bool needs_begin_frames_ = false;
  viz::LocalSurfaceId local_surface_id_;
  std::unique_ptr<viz::ExternalBeginFrameSource> begin_frame_source_;
  std::unique_ptr<viz::SyntheticBeginFrameSource> synthetic_begin_frame_source_;
#if BUILDFLAG(IS_ANDROID)
  base::PlatformThreadId io_thread_id_;
  base::PlatformThreadId main_thread_id_;
#endif

  // Message pipes that will be bound when BindToClient() is called.
  UnboundMessagePipes pipes_;

  mojo::Remote<viz::mojom::CompositorFrameSink> compositor_frame_sink_;
  mojo::AssociatedRemote<viz::mojom::CompositorFrameSink>
      compositor_frame_sink_associated_;
  // One of |compositor_frame_sink_| or |compositor_frame_sink_associated_| will
  // be bound after calling BindToClient(). |compositor_frame_sink_ptr_| will
  // point to message pipe we want to use. It must be declared last and cleared
  // first.
  raw_ptr<viz::mojom::CompositorFrameSink> compositor_frame_sink_ptr_ = nullptr;

  using ClientReceiver = mojo::Receiver<viz::mojom::CompositorFrameSinkClient>;
  using DirectClientReceiver =
      mojo::DirectReceiver<viz::mojom::CompositorFrameSinkClient>;
  std::variant<std::monostate, ClientReceiver, DirectClientReceiver>
      client_receiver_;

  THREAD_CHECKER(thread_checker_);
  const bool wants_animate_only_begin_frames_;

  // Please see comment of `InitParams::auto_needs_begin_frame`.
  const bool auto_needs_begin_frame_;

  viz::HitTestRegionList last_hit_test_data_;

  viz::LocalSurfaceId last_submitted_local_surface_id_;
  float last_submitted_device_scale_factor_ = 1.f;
  gfx::Size last_submitted_size_in_pixels_;

  bool use_begin_frame_presentation_feedback_ = false;
  viz::FrameTimingDetailsMap timing_details_;

  // Use internal delay based begin frame source when there're many undrawn
  // frames recently.
  std::optional<int>
      num_did_not_produce_frame_before_internal_begin_frame_source_;
  uint64_t num_did_not_produce_frame_since_last_submit_ = 0;
  bool use_internal_begin_frame_source_ = false;
  std::unique_ptr<viz::DelayBasedBeginFrameSource> internal_begin_frame_source_;

  base::WeakPtrFactory<AsyncLayerTreeFrameSink> weak_factory_{this};
};

}  // namespace mojo_embedder
}  // namespace cc

#endif  // CC_MOJO_EMBEDDER_ASYNC_LAYER_TREE_FRAME_SINK_H_