// Copyright (c) 2012 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.

#ifndef GPU_IPC_SERVICE_GPU_CHANNEL_H_
#define GPU_IPC_SERVICE_GPU_CHANNEL_H_

#include <stddef.h>
#include <stdint.h>

#include <memory>
#include <string>

#include "base/containers/flat_map.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/weak_ptr.h"
#include "base/process/process.h"
#include "base/single_thread_task_runner.h"
#include "base/trace_event/memory_dump_provider.h"
#include "build/build_config.h"
#include "gpu/command_buffer/common/context_result.h"
#include "gpu/command_buffer/service/sync_point_manager.h"
#include "gpu/ipc/service/command_buffer_stub.h"
#include "gpu/ipc/service/gpu_ipc_service_export.h"
#include "ipc/ipc_sender.h"
#include "ipc/ipc_sync_channel.h"
#include "ipc/message_router.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gfx/native_widget_types.h"
#include "ui/gl/gl_share_group.h"
#include "ui/gl/gpu_preference.h"

struct GPUCreateCommandBufferConfig;

namespace base {
class WaitableEvent;
}

namespace gpu {

class Scheduler;
class SyncPointManager;
class GpuChannelManager;
class GpuChannelMessageFilter;

class GPU_IPC_SERVICE_EXPORT FilteredSender : public IPC::Sender {
 public:
  FilteredSender();
  ~FilteredSender() override;

  virtual void AddFilter(IPC::MessageFilter* filter) = 0;
  virtual void RemoveFilter(IPC::MessageFilter* filter) = 0;
};

class GPU_IPC_SERVICE_EXPORT SyncChannelFilteredSender : public FilteredSender {
 public:
  SyncChannelFilteredSender(
      IPC::ChannelHandle channel_handle,
      IPC::Listener* listener,
      scoped_refptr<base::SingleThreadTaskRunner> ipc_task_runner,
      base::WaitableEvent* shutdown_event);
  ~SyncChannelFilteredSender() override;

  bool Send(IPC::Message* msg) override;
  void AddFilter(IPC::MessageFilter* filter) override;
  void RemoveFilter(IPC::MessageFilter* filter) override;

 private:
  std::unique_ptr<IPC::SyncChannel> channel_;

  DISALLOW_COPY_AND_ASSIGN(SyncChannelFilteredSender);
};

// Encapsulates an IPC channel between the GPU process and one renderer
// process. On the renderer side there's a corresponding GpuChannelHost.
class GPU_IPC_SERVICE_EXPORT GpuChannel : public IPC::Listener,
                                          public FilteredSender {
 public:
  // Takes ownership of the renderer process handle.
  GpuChannel(GpuChannelManager* gpu_channel_manager,
             Scheduler* scheduler,
             SyncPointManager* sync_point_manager,
             scoped_refptr<gl::GLShareGroup> share_group,
             scoped_refptr<base::SingleThreadTaskRunner> task_runner,
             scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
             int32_t client_id,
             uint64_t client_tracing_id,
             bool is_gpu_host);
  ~GpuChannel() override;

  // The IPC channel cannot be passed in the constructor because it needs a
  // listener. The listener is the GpuChannel and must be constructed first.
  void Init(std::unique_ptr<FilteredSender> channel);

  base::WeakPtr<GpuChannel> AsWeakPtr();

  void SetUnhandledMessageListener(IPC::Listener* listener);

  // Get the GpuChannelManager that owns this channel.
  GpuChannelManager* gpu_channel_manager() const {
    return gpu_channel_manager_;
  }

  Scheduler* scheduler() const { return scheduler_; }

  SyncPointManager* sync_point_manager() const { return sync_point_manager_; }

  gles2::ImageManager* image_manager() const { return image_manager_.get(); }

  const scoped_refptr<base::SingleThreadTaskRunner>& task_runner() const {
    return task_runner_;
  }

  base::ProcessId GetClientPID() const;
  bool IsConnected() const;

  int client_id() const { return client_id_; }

  uint64_t client_tracing_id() const { return client_tracing_id_; }

  const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner() const {
    return io_task_runner_;
  }

  FilteredSender* channel_for_testing() const { return channel_.get(); }

  // IPC::Listener implementation:
  bool OnMessageReceived(const IPC::Message& msg) override;
  void OnChannelConnected(int32_t peer_pid) override;
  void OnChannelError() override;

  // FilteredSender implementation:
  bool Send(IPC::Message* msg) override;
  void AddFilter(IPC::MessageFilter* filter) override;
  void RemoveFilter(IPC::MessageFilter* filter) override;

  void OnCommandBufferScheduled(CommandBufferStub* stub);
  void OnCommandBufferDescheduled(CommandBufferStub* stub);

  gl::GLShareGroup* share_group() const { return share_group_.get(); }

  CommandBufferStub* LookupCommandBuffer(int32_t route_id);

  bool HasActiveWebGLContext() const;
  void LoseAllContexts();
  void MarkAllContextsLost();

  // Called to add a listener for a particular message routing ID.
  // Returns true if succeeded.
  bool AddRoute(int32_t route_id,
                SequenceId sequence_id,
                IPC::Listener* listener);

  // Called to remove a listener for a particular message routing ID.
  void RemoveRoute(int32_t route_id);

  void CacheShader(const std::string& key, const std::string& shader);

  uint64_t GetMemoryUsage() const;

  scoped_refptr<gl::GLImage> CreateImageForGpuMemoryBuffer(
      const gfx::GpuMemoryBufferHandle& handle,
      const gfx::Size& size,
      gfx::BufferFormat format,
      uint32_t internalformat,
      SurfaceHandle surface_handle);

  void HandleMessage(const IPC::Message& msg);

  // Some messages such as WaitForGetOffsetInRange and WaitForTokenInRange are
  // processed as soon as possible because the client is blocked until they
  // are completed.
  void HandleOutOfOrderMessage(const IPC::Message& msg);

  void HandleMessageForTesting(const IPC::Message& msg);

#if defined(OS_ANDROID)
  const CommandBufferStub* GetOneStub() const;
#endif

 private:
  bool OnControlMessageReceived(const IPC::Message& msg);

  void HandleMessageHelper(const IPC::Message& msg);

  // Message handlers for control messages.
  void OnCreateCommandBuffer(const GPUCreateCommandBufferConfig& init_params,
                             int32_t route_id,
                             base::UnsafeSharedMemoryRegion shared_state_shm,
                             gpu::ContextResult* result,
                             gpu::Capabilities* capabilities);
  void OnDestroyCommandBuffer(int32_t route_id);

  std::unique_ptr<FilteredSender> channel_;

  base::ProcessId peer_pid_ = base::kNullProcessId;

  // The message filter on the io thread.
  scoped_refptr<GpuChannelMessageFilter> filter_;

  // Map of routing id to command buffer stub.
  base::flat_map<int32_t, std::unique_ptr<CommandBufferStub>> stubs_;

  // Map of stream id to scheduler sequence id.
  base::flat_map<int32_t, SequenceId> stream_sequences_;

  // The lifetime of objects of this class is managed by a GpuChannelManager.
  // The GpuChannelManager destroy all the GpuChannels that they own when they
  // are destroyed. So a raw pointer is safe.
  GpuChannelManager* const gpu_channel_manager_;

  Scheduler* const scheduler_;

  // Sync point manager. Outlives the channel and is guaranteed to outlive the
  // message loop.
  SyncPointManager* const sync_point_manager_;

  IPC::Listener* unhandled_message_listener_ = nullptr;

  // Used to implement message routing functionality to CommandBuffer objects
  IPC::MessageRouter router_;

  // The id of the client who is on the other side of the channel.
  const int32_t client_id_;

  // The tracing ID used for memory allocations associated with this client.
  const uint64_t client_tracing_id_;

  // The task runners for the main thread and the io thread.
  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
  scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;

  // The share group that all contexts associated with a particular renderer
  // process use.
  scoped_refptr<gl::GLShareGroup> share_group_;

  std::unique_ptr<gles2::ImageManager> image_manager_;

  const bool is_gpu_host_;

  // Member variables should appear before the WeakPtrFactory, to ensure that
  // any WeakPtrs to Controller are invalidated before its members variable's
  // destructors are executed, rendering them invalid.
  base::WeakPtrFactory<GpuChannel> weak_factory_;

  DISALLOW_COPY_AND_ASSIGN(GpuChannel);
};

}  // namespace gpu

#endif  // GPU_IPC_SERVICE_GPU_CHANNEL_H_