// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "third_party/blink/renderer/platform/widget/compositing/layer_tree_view.h"

#include <stddef.h>

#include <string>
#include <utility>

#include "base/feature_list.h"
#include "base/functional/bind.h"
#include "base/functional/callback.h"
#include "base/location.h"
#include "base/logging.h"
#include "base/metrics/histogram_macros.h"
#include "base/task/single_thread_task_runner.h"
#include "base/task/task_traits.h"
#include "base/task/thread_pool.h"
#include "base/task/thread_pool/thread_pool_instance.h"
#include "base/time/time.h"
#include "base/values.h"
#include "cc/animation/animation_host.h"
#include "cc/animation/animation_timeline.h"
#include "cc/base/region.h"
#include "cc/benchmarks/micro_benchmark.h"
#include "cc/debug/layer_tree_debug_state.h"
#include "cc/input/layer_selection_bound.h"
#include "cc/layers/layer.h"
#include "cc/tiles/raster_dark_mode_filter.h"
#include "cc/trees/layer_tree_host.h"
#include "cc/trees/layer_tree_mutator.h"
#include "cc/trees/paint_holding_reason.h"
#include "cc/trees/presentation_time_callback_buffer.h"
#include "cc/trees/render_frame_metadata_observer.h"
#include "cc/trees/swap_promise.h"
#include "components/viz/common/frame_sinks/begin_frame_args.h"
#include "components/viz/common/frame_sinks/begin_frame_source.h"
#include "components/viz/common/quads/compositor_frame_metadata.h"
#include "services/metrics/public/cpp/mojo_ukm_recorder.h"
#include "third_party/blink/public/common/thread_safe_browser_interface_broker_proxy.h"
#include "third_party/blink/public/platform/platform.h"
#include "third_party/blink/public/strings/grit/blink_strings.h"
#include "third_party/blink/renderer/platform/graphics/dark_mode_filter.h"
#include "third_party/blink/renderer/platform/graphics/dark_mode_settings_builder.h"
#include "third_party/blink/renderer/platform/graphics/raster_dark_mode_filter_impl.h"
#include "third_party/blink/renderer/platform/scheduler/public/widget_scheduler.h"
#include "ui/gfx/presentation_feedback.h"

namespace cc {
class Layer;
}

namespace blink {

namespace {
}  // namespace

LayerTreeView::LayerTreeView(
    LayerTreeViewDelegate* delegate,
    scoped_refptr<scheduler::WidgetScheduler> scheduler)
    : widget_scheduler_(std::move(scheduler)),
      animation_host_(cc::AnimationHost::CreateMainInstance()),
      delegate_(delegate) {}

LayerTreeView::~LayerTreeView() = default;

void LayerTreeView::Initialize(
    const cc::LayerTreeSettings& settings,
    scoped_refptr<base::SingleThreadTaskRunner> main_thread,
    scoped_refptr<base::SingleThreadTaskRunner> compositor_thread,
    cc::TaskGraphRunner* task_graph_runner) {
  DCHECK(delegate_);
  const bool is_threaded = !!compositor_thread;

  cc::LayerTreeHost::InitParams params;
  params.client = this;
  params.scheduling_delegate = this;
  params.settings = &settings;
  params.task_graph_runner = task_graph_runner;
  params.main_task_runner = std::move(main_thread);
  params.mutator_host = animation_host_.get();
  params.dark_mode_filter = &RasterDarkModeFilterImpl::Instance();
  if (base::ThreadPoolInstance::Get()) {
    // The image worker thread needs to allow waiting since it makes discardable
    // shared memory allocations which need to make synchronous calls to the
    // IO thread.
    params.image_worker_task_runner =
        base::ThreadPool::CreateSequencedTaskRunner(
            {base::WithBaseSyncPrimitives(), base::TaskPriority::USER_VISIBLE,
             base::TaskShutdownBehavior::CONTINUE_ON_SHUTDOWN});
  }
  if (!is_threaded) {
    // Single-threaded web tests, and unit tests.
    layer_tree_host_ =
        cc::LayerTreeHost::CreateSingleThreaded(this, std::move(params));
  } else {
    layer_tree_host_ =
        cc::LayerTreeHost::CreateThreaded(std::move(compositor_thread), std::move(params));
  }

  first_source_frame_for_current_delegate_ =
      layer_tree_host_->SourceFrameNumber();
}

void LayerTreeView::Disconnect() {
  DCHECK(delegate_);
  // Drop compositor resources immediately, while keeping the compositor alive
  // until after this class is destroyed.
  layer_tree_host_->WaitForProtectedSequenceCompletion();
  layer_tree_host_->SetVisible(false);
  layer_tree_host_->ReleaseLayerTreeFrameSink();
  delegate_ = nullptr;
}

void LayerTreeView::ClearPreviousDelegateAndReattachIfNeeded(
    LayerTreeViewDelegate* delegate,
    scoped_refptr<scheduler::WidgetScheduler> scheduler) {
  // Reset state tied to the previous `delegate_`.
  layer_tree_host_->WaitForProtectedSequenceCompletion();

  if (!delegate) {
    // If we're not reattaching to a new delegate, ensure that the LayerTreeHost
    // is no longer visible. Note that this should be done before calling
    // `LayerTreeHost::DetachInputDelegateAndRenderFrameObserver()` to avoid
    // having a gap in time in the compositor where the LayerTreeHost is already
    // detached but is still marked as visible. This is done to stop the compositor from producing frames which require an input delegate. See also
    // https://crbug.com/41496745 for more details.
    layer_tree_host_->SetVisible(false);
  }
  layer_tree_host_->DetachInputDelegateAndRenderFrameObserver();
  layer_tree_host_->StopDeferringCommits();
  for (uint32_t i = 0;
       i <= static_cast<uint32_t>(cc::EventListenerClass::kLast); ++i) {
    layer_tree_host_->SetEventListenerProperties(
        static_cast<cc::EventListenerClass>(i),
        cc::EventListenerProperties::kNone);
  }

  delegate_ = delegate;
  CHECK_GE(layer_tree_host_->SourceFrameNumber(),
           first_source_frame_for_current_delegate_)
      << "SourceFrameNumber() must be monotonically increasing";
  first_source_frame_for_current_delegate_ =
      layer_tree_host_->SourceFrameNumber();
  widget_scheduler_ = std::move(scheduler);

  // Invalidate weak ptrs so callbacks from the previous delegate are dropped.
  weak_factory_for_delegate_.InvalidateWeakPtrs();

  if (!delegate) {
    return;
  }

  switch (frame_sink_state_) {
    case FrameSinkState::kNoFrameSink:
      // No frame sink, the LTH should issue a request which will set both the
      // frame sink and RenderFrameObserver.
      break;
    case FrameSinkState::kRequestBufferedInvisible:
      // The frame sink request was buffered because it was made when the LTH
      // was invisible. It will be issued when the LTH is made visible.
      break;
    case FrameSinkState::kRequestPending:
      // If the request was pending, it targeted the previous delegate and we
      // cancelled it by invalidating the weak pointers above. Re-issue it
      // targeting the new delegate.
      DidFailToInitializeLayerTreeFrameSink();
      break;
    case FrameSinkState::kInitializing:
      // The LTH is initializing a new FrameSink which can be reused but we need
      // a new RenderFrameObserver associated with the new delegate.
    case FrameSinkState::kInitialized:
      // The LTH has an initialized FrameSink which can be reused but we need a
      // new RenderFrameObserver associated with the new delegate.
      if (auto render_frame_observer = delegate_->CreateRenderFrameObserver()) {
        layer_tree_host_->SetRenderFrameObserver(
            std::move(render_frame_observer));
      }
      break;
  }
}

void LayerTreeView::SetVisible(bool visible) {
  DCHECK(delegate_);
  layer_tree_host_->SetVisible(visible);

  if (visible &&
      frame_sink_state_ == FrameSinkState::kRequestBufferedInvisible) {
    DidFailToInitializeLayerTreeFrameSink();
  }
}

void LayerTreeView::SetShouldWarmUp() {
  DCHECK(delegate_);
  layer_tree_host_->SetShouldWarmUp();
}

void LayerTreeView::SetLayerTreeFrameSink(
    std::unique_ptr<cc::LayerTreeFrameSink> layer_tree_frame_sink,
    std::unique_ptr<cc::RenderFrameMetadataObserver>
        render_frame_metadata_observer) {
  DCHECK(delegate_);

  CHECK_EQ(frame_sink_state_, FrameSinkState::kRequestPending);
  frame_sink_state_ = FrameSinkState::kInitializing;

  if (!layer_tree_frame_sink) {
    DidFailToInitializeLayerTreeFrameSink();
    return;
  }
  if (render_frame_metadata_observer) {
    layer_tree_host_->SetRenderFrameObserver(
        std::move(render_frame_metadata_observer));
  }
  layer_tree_host_->SetLayerTreeFrameSink(std::move(layer_tree_frame_sink));
}

void LayerTreeView::WillBeginMainFrame() {
  if (!delegate_)
    return;
  delegate_->WillBeginMainFrame();
}

void LayerTreeView::DidBeginMainFrame() {
  if (!delegate_)
    return;
  delegate_->DidBeginMainFrame();
}

void LayerTreeView::WillUpdateLayers() {
  if (!delegate_)
    return;
  delegate_->BeginUpdateLayers();
}

void LayerTreeView::DidUpdateLayers() {
  if (!delegate_)
    return;
  delegate_->EndUpdateLayers();
  // Dump property trees and layers if run with:
  //   --vmodule=layer_tree_view=3
  VLOG(3) << "After updating layers:\n"
          << "property trees:\n"
          << layer_tree_host_->property_trees()->ToString() << "\n"
          << "cc::Layers:\n"
          << layer_tree_host_->LayersAsString();
}

void LayerTreeView::BeginMainFrame(const viz::BeginFrameArgs& args) {
  if (!delegate_)
    return;
  widget_scheduler_->WillBeginFrame(args);
  delegate_->BeginMainFrame(args);
}

void LayerTreeView::OnDeferMainFrameUpdatesChanged(bool status) {
  if (!delegate_)
    return;
  delegate_->OnDeferMainFrameUpdatesChanged(status);
}

void LayerTreeView::OnCommitRequested() {
  if (!delegate_)
    return;
  delegate_->OnCommitRequested();
}

void LayerTreeView::OnDeferCommitsChanged(bool status,
                                          cc::PaintHoldingReason reason) {
  if (!delegate_)
    return;
  delegate_->OnDeferCommitsChanged(status, reason);
}

void LayerTreeView::BeginMainFrameNotExpectedSoon() {
  if (!delegate_)
    return;
  widget_scheduler_->BeginFrameNotExpectedSoon();
}

void LayerTreeView::BeginMainFrameNotExpectedUntil(base::TimeTicks time) {
  if (!delegate_)
    return;
  widget_scheduler_->BeginMainFrameNotExpectedUntil(time);
}

void LayerTreeView::UpdateLayerTreeHost() {
  if (!delegate_)
    return;
  delegate_->UpdateVisualState();
}

void LayerTreeView::ApplyViewportChanges(
    const cc::ApplyViewportChangesArgs& args) {
  if (!delegate_)
    return;
  delegate_->ApplyViewportChanges(args);
}

void LayerTreeView::UpdateCompositorScrollState(
    const cc::CompositorCommitData& commit_data) {
  if (!delegate_)
    return;
  delegate_->UpdateCompositorScrollState(commit_data);
}

void LayerTreeView::UpdateAnimatedImageState(
    const cc::CompositorCommitData& commit_data) {
  if (!delegate_) {
    return;
  }
  delegate_->UpdateAnimatedImageState(commit_data);
}

void LayerTreeView::RequestNewLayerTreeFrameSink() {
  if (!delegate_)
    return;

  CHECK(frame_sink_state_ == FrameSinkState::kNoFrameSink ||
        frame_sink_state_ == FrameSinkState::kInitialized);

  // When the compositor is not visible it would not request a
  // LayerTreeFrameSink so this is a race where it requested one on the
  // compositor thread while becoming non-visible on the main thread. In that
  // case, we can wait for it to become visible again before replying.
  // If the warm-up is triggered, a LayerTreeFrameSink is requested even if
  // non-visible state. We can ignore this branch in that case.
  if (!layer_tree_host_->ShouldWarmUp() && !layer_tree_host_->IsVisible()) {
    frame_sink_state_ = FrameSinkState::kRequestBufferedInvisible;
    return;
  }

  frame_sink_state_ = FrameSinkState::kRequestPending;
  delegate_->RequestNewLayerTreeFrameSink(
      base::BindOnce(&LayerTreeView::SetLayerTreeFrameSink,
                     weak_factory_for_delegate_.GetWeakPtr()));
}

void LayerTreeView::DidInitializeLayerTreeFrameSink() {
  CHECK_EQ(frame_sink_state_, FrameSinkState::kInitializing);
  frame_sink_state_ = FrameSinkState::kInitialized;
}

void LayerTreeView::DidFailToInitializeLayerTreeFrameSink() {
  if (!delegate_)
    return;

  CHECK(frame_sink_state_ == FrameSinkState::kRequestBufferedInvisible ||
        frame_sink_state_ == FrameSinkState::kInitializing ||
        frame_sink_state_ == FrameSinkState::kRequestPending);

  // When the RenderWidget is made hidden while an async request for a
  // LayerTreeFrameSink is being processed, then if it fails we would arrive
  // here. Since the compositor does not request a LayerTreeFrameSink while not
  // visible, we can delay trying again until becoming visible again.
  // If the warm-up is triggered, a LayerTreeFrameSink is requested even if
  // non-visible state. We can ignore this branch in that case.
  if (!layer_tree_host_->ShouldWarmUp() && !layer_tree_host_->IsVisible()) {
    frame_sink_state_ = FrameSinkState::kRequestBufferedInvisible;
    return;
  }

  frame_sink_state_ = FrameSinkState::kNoFrameSink;
  // The GPU channel cannot be established when gpu_remote is disconnected. Stop
  // calling RequestNewLayerTreeFrameSink because it's going to fail again and
  // it will be stuck in a forever loop of retries. This makes the processes
  // unable to be killed after Chrome is closed.
  // https://issues.chromium.org/336164423
  if (!Platform::Current()->IsGpuRemoteDisconnected()) {
    // Run this task on a default priority task runner, so we don't starve mojo
    // messages while we're in a retry loop.
    base::SingleThreadTaskRunner::GetCurrentDefault()->PostTask(
        FROM_HERE, base::BindOnce(&LayerTreeView::RequestNewLayerTreeFrameSink,
                                  weak_factory_.GetWeakPtr()));
  }
}

void LayerTreeView::WillCommit(const cc::CommitState&) {
  if (!delegate_)
    return;
  delegate_->WillCommitCompositorFrame();
  widget_scheduler_->DidCommitFrameToCompositor();
}

void LayerTreeView::DidCommit(int source_frame_number,
                              base::TimeTicks commit_start_time,
                              base::TimeTicks commit_finish_time) {
  if (!delegate_ ||
      source_frame_number < first_source_frame_for_current_delegate_) {
    return;
  }
  delegate_->DidCommitCompositorFrame(commit_start_time, commit_finish_time);
}

void LayerTreeView::DidCommitAndDrawFrame(int source_frame_number) {
  if (!delegate_ ||
      source_frame_number < first_source_frame_for_current_delegate_) {
    return;
  }
  delegate_->DidCommitAndDrawCompositorFrame();
}

void LayerTreeView::DidCompletePageScaleAnimation(int source_frame_number) {
  if (!delegate_ ||
      source_frame_number < first_source_frame_for_current_delegate_) {
    return;
  }
  delegate_->DidCompletePageScaleAnimation();
}

void LayerTreeView::DidPresentCompositorFrame(
    uint32_t frame_token,
    const viz::FrameTimingDetails& frame_timing_details) {
  if (!delegate_)
    return;
  DCHECK(layer_tree_host_->GetTaskRunnerProvider()
             ->MainThreadTaskRunner()
             ->RunsTasksInCurrentSequence());
  // Only run callbacks on successful presentations.
  if (frame_timing_details.presentation_feedback.failed()) {
    return;
  }
  while (!presentation_callbacks_.empty()) {
    const auto& front = presentation_callbacks_.begin();
    if (front->first > frame_token) {
      break;
    }
    for (auto& callback : front->second)
      std::move(callback).Run(frame_timing_details);
    presentation_callbacks_.erase(front);
  }

#if BUILDFLAG(IS_APPLE)
  while (!core_animation_error_code_callbacks_.empty()) {
    const auto& front = core_animation_error_code_callbacks_.begin();
    if (front->first > frame_token) {
      break;
    }
    for (auto& callback : front->second) {
      std::move(callback).Run(
          frame_timing_details.presentation_feedback.ca_layer_error_code);
    }
    core_animation_error_code_callbacks_.erase(front);
  }
#endif
}

void LayerTreeView::RecordStartOfFrameMetrics() {
  if (!delegate_)
    return;
  delegate_->RecordStartOfFrameMetrics();
}

void LayerTreeView::RecordEndOfFrameMetrics(
    base::TimeTicks frame_begin_time,
    cc::ActiveFrameSequenceTrackers trackers) {
  if (!delegate_)
    return;
  delegate_->RecordEndOfFrameMetrics(frame_begin_time, trackers);
}

std::unique_ptr<cc::BeginMainFrameMetrics>
LayerTreeView::GetBeginMainFrameMetrics() {
  if (!delegate_)
    return nullptr;
  return delegate_->GetBeginMainFrameMetrics();
}

void LayerTreeView::NotifyCompositorMetricsTrackerResults(
    cc::CustomTrackerResults results) {
  NOTREACHED();
}

void LayerTreeView::DidObserveFirstScrollDelay(
    int source_frame_number,
    base::TimeDelta first_scroll_delay,
    base::TimeTicks first_scroll_timestamp) {
  if (!delegate_ ||
      source_frame_number < first_source_frame_for_current_delegate_) {
    return;
  }
  delegate_->DidObserveFirstScrollDelay(first_scroll_delay,
                                        first_scroll_timestamp);
}

void LayerTreeView::RunPaintBenchmark(int repeat_count,
                                      cc::PaintBenchmarkResult& result) {
  if (delegate_)
    delegate_->RunPaintBenchmark(repeat_count, result);
}

std::string LayerTreeView::GetPausedDebuggerLocalizedMessage() {
  return Platform::Current()
      ->QueryLocalizedString(IDS_DEBUGGER_PAUSED_IN_ANOTHER_TAB)
      .Utf8();
}

void LayerTreeView::DidRunBeginMainFrame() {
  if (!delegate_)
    return;

  widget_scheduler_->DidRunBeginMainFrame();
}

void LayerTreeView::DidSubmitCompositorFrame() {}

void LayerTreeView::DidLoseLayerTreeFrameSink() {}

void LayerTreeView::ScheduleAnimationForWebTests() {
  if (!delegate_)
    return;

  delegate_->ScheduleAnimationForWebTests();
}

void LayerTreeView::AddPresentationCallback(
    uint32_t frame_token,
    base::OnceCallback<void(const viz::FrameTimingDetails&)> callback) {
  AddCallback(frame_token, std::move(callback), presentation_callbacks_);
}

#if BUILDFLAG(IS_APPLE)
void LayerTreeView::AddCoreAnimationErrorCodeCallback(
    uint32_t frame_token,
    base::OnceCallback<void(gfx::CALayerResult)> callback) {
  AddCallback(frame_token, std::move(callback),
              core_animation_error_code_callbacks_);
}
#endif

template <typename Callback>
void LayerTreeView::AddCallback(
    uint32_t frame_token,
    Callback callback,
    base::circular_deque<std::pair<uint32_t, std::vector<Callback>>>&
        callbacks) {
  DCHECK(delegate_);
  if (!callbacks.empty()) {
    auto& previous = callbacks.back();
    uint32_t previous_frame_token = previous.first;
    if (previous_frame_token == frame_token) {
      previous.second.push_back(std::move(callback));
      DCHECK_LE(previous.second.size(), 250u);
      return;
    }
    DCHECK_GT(frame_token, previous_frame_token);
  }
  std::vector<Callback> new_callbacks;
  new_callbacks.push_back(std::move(callback));
  callbacks.emplace_back(frame_token, std::move(new_callbacks));
  DCHECK_LE(callbacks.size(),
            cc::PresentationTimeCallbackBuffer::kMaxBufferSize);
}

}  // namespace blink