// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/renderer/media/android/stream_texture_factory.h"

#include "base/functional/bind.h"
#include "base/logging.h"
#include "base/task/single_thread_task_runner.h"
#include "gpu/ipc/client/client_shared_image_interface.h"
#include "gpu/ipc/client/gpu_channel_host.h"
#include "gpu/ipc/common/gpu_channel.mojom.h"
#include "mojo/public/cpp/bindings/pending_associated_remote.h"
#include "mojo/public/cpp/bindings/sync_call_restrictions.h"
#include "ui/gfx/geometry/size.h"

namespace content {

StreamTextureProxy::StreamTextureProxy(std::unique_ptr<StreamTextureHost> host)
    : host_(std::move(host)) {}

StreamTextureProxy::~StreamTextureProxy() {}

void StreamTextureProxy::Release() {
  // Cannot call |received_frame_cb_| after returning from here.
  ClearReceivedFrameCB();

  // |this| can be deleted by the |task_runner_| on the compositor thread by
  // posting task to that thread. So we need to clear the
  // |create_video_frame_cb_| here first so that its not called on the
  // compositor thread before |this| is deleted. The problem is that
  // |create_video_frame_cb_| is provided by the owner of StreamTextureProxy,
  // which is being destroyed and is releasing StreamTextureProxy.
  ClearCreateVideoFrameCB();

  // Release is analogous to the destructor, so there should be no more external
  // calls to this object in Release. Therefore there is no need to acquire the
  // lock to access |task_runner_|.
  if (!task_runner_.get() || task_runner_->BelongsToCurrentThread() ||
      !task_runner_->DeleteSoon(FROM_HERE, this)) {
    delete this;
  }
}

void StreamTextureProxy::ClearReceivedFrameCB() {
  base::AutoLock lock(lock_);
  received_frame_cb_.Reset();
}

void StreamTextureProxy::ClearCreateVideoFrameCB() {
  base::AutoLock lock(lock_);
  create_video_frame_cb_.Reset();
}

void StreamTextureProxy::BindToTaskRunner(
    const base::RepeatingClosure& received_frame_cb,
    const CreateVideoFrameCB& create_video_frame_cb,
    scoped_refptr<base::SingleThreadTaskRunner> task_runner) {
  DCHECK(task_runner.get());

  {
    base::AutoLock lock(lock_);
    DCHECK(!task_runner_.get() || (task_runner.get() == task_runner_.get()));
    task_runner_ = task_runner;
    received_frame_cb_ = received_frame_cb;
    create_video_frame_cb_ = create_video_frame_cb;
  }

  if (task_runner->BelongsToCurrentThread()) {
    BindOnThread();
    return;
  }
  // Unretained is safe here only because the object is deleted on |loop_|
  // thread.
  task_runner->PostTask(FROM_HERE,
                        base::BindOnce(&StreamTextureProxy::BindOnThread,
                                       base::Unretained(this)));
}

void StreamTextureProxy::BindOnThread() {
  host_->BindToCurrentThread(this);
}

void StreamTextureProxy::OnFrameAvailable() {
  base::AutoLock lock(lock_);
  if (!received_frame_cb_.is_null())
    received_frame_cb_.Run();
}

void StreamTextureProxy::OnFrameWithInfoAvailable(
    const gpu::Mailbox& mailbox,
    const gfx::Size& coded_size,
    const gfx::Rect& visible_rect,
    const absl::optional<gpu::VulkanYCbCrInfo>& ycbcr_info) {
  base::AutoLock lock(lock_);
  // Set the ycbcr info before running the received frame callback so that the
  // first frame has it.
  if (!create_video_frame_cb_.is_null())
    create_video_frame_cb_.Run(mailbox, coded_size, visible_rect, ycbcr_info);
  if (!received_frame_cb_.is_null())
    received_frame_cb_.Run();
}

void StreamTextureProxy::ForwardStreamTextureForSurfaceRequest(
    const base::UnguessableToken& request_token) {
  base::AutoLock lock(lock_);
  if (!task_runner_)
    return;

  if (!task_runner_->BelongsToCurrentThread()) {
    // Note that Unretained is safe here because this object is deleted
    // exclusively by posting a task to the same task runner, after its owner
    // has dropped the only reference to it.
    task_runner_->PostTask(
        FROM_HERE,
        base::BindOnce(
            &StreamTextureProxy::ForwardStreamTextureForSurfaceRequest,
            base::Unretained(this), request_token));
    return;
  }

  host_->ForwardStreamTextureForSurfaceRequest(request_token);
}

void StreamTextureProxy::UpdateRotatedVisibleSize(const gfx::Size& size) {
  base::AutoLock lock(lock_);
  if (!task_runner_)
    return;

  if (!task_runner_->BelongsToCurrentThread()) {
    // Note that Unretained is safe here because this object is deleted
    // exclusively by posting a task to the same task runner, after its owner
    // has dropped the only reference to it.
    task_runner_->PostTask(
        FROM_HERE, base::BindOnce(&StreamTextureProxy::UpdateRotatedVisibleSize,
                                  base::Unretained(this), size));
    return;
  }
  host_->UpdateRotatedVisibleSize(size);
}

// static
scoped_refptr<StreamTextureFactory> StreamTextureFactory::Create(
    scoped_refptr<gpu::GpuChannelHost> channel) {
  return new StreamTextureFactory(std::move(channel));
}

StreamTextureFactory::StreamTextureFactory(
    scoped_refptr<gpu::GpuChannelHost> channel)
    : channel_(std::move(channel)) {
  DCHECK(channel_);
}

StreamTextureFactory::~StreamTextureFactory() = default;

ScopedStreamTextureProxy StreamTextureFactory::CreateProxy() {
  // Send a StreamTexure receiver down to the GPU process. This will be bound to
  // a concrete StreamTexture impl there.
  int32_t stream_id = channel_->GenerateRouteID();
  bool succeeded = false;
  mojo::SyncCallRestrictions::ScopedAllowSyncCall allow_sync;
  mojo::PendingAssociatedRemote<gpu::mojom::StreamTexture> remote;
  channel_->GetGpuChannel().CreateStreamTexture(
      stream_id, remote.InitWithNewEndpointAndPassReceiver(), &succeeded);
  if (!succeeded) {
    DLOG(ERROR) << "CreateStreamTexture failed";
    return ScopedStreamTextureProxy();
  }

  // Now instantiate a new StreamTextureHost here to remotely control the new
  // GPU-side StreamTexture instance.
  return ScopedStreamTextureProxy(
      new StreamTextureProxy(std::make_unique<StreamTextureHost>(
          channel_, stream_id, std::move(remote))));
}

bool StreamTextureFactory::IsLost() const {
  return channel_->IsLost();
}

gpu::SharedImageInterface* StreamTextureFactory::SharedImageInterface() {
  if (shared_image_interface_)
    return shared_image_interface_.get();

  shared_image_interface_ = channel_->CreateClientSharedImageInterface();
  DCHECK(shared_image_interface_);
  return shared_image_interface_.get();
}

}  // namespace content