// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CHROME_BROWSER_TASK_MANAGER_SAMPLING_TASK_MANAGER_IMPL_H_
#define CHROME_BROWSER_TASK_MANAGER_SAMPLING_TASK_MANAGER_IMPL_H_

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

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

#include "base/byte_size.h"
#include "base/containers/flat_map.h"
#include "base/memory/raw_ptr.h"
#include "base/memory/weak_ptr.h"
#include "base/no_destructor.h"
#include "base/task/sequenced_task_runner.h"
#include "base/time/time.h"
#include "chrome/browser/task_manager/providers/task_provider.h"
#include "chrome/browser/task_manager/providers/task_provider_observer.h"
#include "chrome/browser/task_manager/sampling/task_group.h"
#include "chrome/browser/task_manager/task_manager_interface.h"
#include "content/public/browser/global_routing_id.h"
#include "gpu/ipc/common/memory_stats.h"
#include "services/resource_coordinator/public/cpp/memory_instrumentation/global_memory_dump.h"

#if BUILDFLAG(IS_CHROMEOS)
#include "chrome/browser/task_manager/sampling/arc_shared_sampler.h"
#endif  // BUILDFLAG(IS_CHROMEOS)

namespace task_manager {

class SharedSampler;

// Defines a concrete implementation of the TaskManagerInterface.
class TaskManagerImpl : public TaskManagerInterface,
                        public TaskProviderObserver {
 public:
  TaskManagerImpl(const TaskManagerImpl&) = delete;
  TaskManagerImpl& operator=(const TaskManagerImpl&) = delete;
  ~TaskManagerImpl() override;

  static TaskManagerImpl* GetInstance();
  static bool IsCreated();

  // task_manager::TaskManagerInterface:
  void ActivateTask(TaskId task_id) override;
  bool IsTaskKillable(TaskId task_id) override;
  bool KillTask(TaskId task_id) override;
  double GetPlatformIndependentCPUUsage(TaskId task_id) const override;
  base::Time GetStartTime(TaskId task_id) const override;
  base::TimeDelta GetCpuTime(TaskId task_id) const override;
  std::optional<base::ByteSize> GetMemoryFootprintUsage(
      TaskId task_id) const override;
  std::optional<base::ByteSize> GetSwappedMemoryUsage(
      TaskId task_id) const override;
  std::optional<base::ByteSize> GetGpuMemoryUsage(
      TaskId task_id,
      bool* has_duplicates) const override;
  int GetIdleWakeupsPerSecond(TaskId task_id) const override;
  int GetHardFaultsPerSecond(TaskId task_id) const override;
  void GetGDIHandles(TaskId task_id,
                     int64_t* current,
                     int64_t* peak) const override;
  void GetUSERHandles(TaskId task_id,
                      int64_t* current,
                      int64_t* peak) const override;
  int GetOpenFdCount(TaskId task_id) const override;
  bool IsTaskOnBackgroundedProcess(TaskId task_id) const override;
  const std::u16string& GetTitle(TaskId task_id) const override;
  std::u16string GetProfileName(TaskId task_id) const override;
  const gfx::ImageSkia& GetIcon(TaskId task_id) const override;
  const base::ProcessHandle& GetProcessHandle(TaskId task_id) const override;
  const base::ProcessId& GetProcessId(TaskId task_id) const override;
  TaskId GetRootTaskId(TaskId task_id) const override;
  Task::Type GetType(TaskId task_id) const override;
  Task::SubType GetSubType(TaskId task_id) const override;
  SessionID GetTabId(TaskId task_id) const override;
  int GetChildProcessUniqueId(TaskId task_id) const override;
  void GetTerminationStatus(TaskId task_id,
                            base::TerminationStatus* out_status,
                            int* out_error_code) const override;
  base::ByteSize GetNetworkUsage(TaskId task_id) const override;
  base::ByteSize GetCumulativeNetworkUsage(TaskId task_id) const override;
  std::optional<base::ByteSize> GetProcessTotalNetworkUsage(
      TaskId task_id) const override;
  std::optional<base::ByteSize> GetSqliteMemoryUsed(
      TaskId task_id) const override;
  bool GetV8Memory(TaskId task_id,
                   base::ByteSize* allocated,
                   base::ByteSize* used) const override;
  bool GetWebCacheStats(TaskId task_id,
                        blink::WebCacheResourceTypeStats* stats) const override;
  int GetKeepaliveCount(TaskId task_id) const override;
  const TaskIdList& GetTaskIdsList() const override;
  TaskIdList GetIdsOfTasksSharingSameProcess(TaskId task_id) const override;
  size_t GetNumberOfTasksOnSameProcess(TaskId task_id) const override;
  bool IsRunningInVM(TaskId task_id) const override;
  TaskId GetTaskIdForWebContents(
      content::WebContents* web_contents) const override;
  bool IsTaskValid(TaskId task_id) const override;

  // task_manager::TaskProviderObserver:
  void TaskAdded(Task* task) override;
  void TaskRemoved(Task* task) override;
  void TaskUnresponsive(Task* task) override;
#if BUILDFLAG(IS_CHROMEOS)
  void TaskIdsListToBeInvalidated() override;
#endif

  void UpdateAccumulatedStatsNetworkForRoute(
      content::GlobalRenderFrameHostId render_frame_host_id,
      base::ByteSize recv_bytes,
      base::ByteSize sent_bytes);

  bool is_running() const { return is_running_; }

 private:
  using PidToTaskGroupMap =
      base::flat_map<base::ProcessId, std::unique_ptr<TaskGroup>>;

  friend class base::NoDestructor<TaskManagerImpl>;

  TaskManagerImpl();

  void OnVideoMemoryUsageStatsUpdate(
      const gpu::VideoMemoryUsageStats& gpu_memory_stats);
  void OnReceivedMemoryDump(
      memory_instrumentation::mojom::RequestOutcome outcome,
      std::unique_ptr<memory_instrumentation::GlobalMemoryDump> dump);

  // task_manager::TaskManagerInterface:
  void Refresh() override;
  void StartUpdating() override;
  void StopUpdating() override;

  // Lookup a task by the global RenderFrameHost id. The empty
  // GlobalRenderFrameHostId works as well, which would lead to the task
  // being attributed to the browser process.
  Task* GetTaskByRoute(
      content::GlobalRenderFrameHostId render_frame_host_id) const;

  PidToTaskGroupMap* GetVmPidToTaskGroupMap(Task::Type type);
  TaskGroup* GetTaskGroupByTaskId(TaskId task_id) const;
  Task* GetTaskByTaskId(TaskId task_id) const;

  // Called back by a TaskGroup when the resource calculations done on the
  // background thread has completed.
  void OnTaskGroupBackgroundCalculationsDone();

  const base::RepeatingClosure on_background_data_ready_callback_;

  // Map TaskGroups by the IDs of the processes they represent.
  PidToTaskGroupMap task_groups_by_proc_id_;

  // Map ARC VM PidToTaskGroupMaps by the task type. This should be separate
  // from the non-VM map |task_groups_by_proc_id_| as there can be conflicting
  // PIDs.
  PidToTaskGroupMap arc_vm_task_groups_by_proc_id_;

  // Map each task by its ID to the TaskGroup on which it resides.
  // Keys are unique but values will have duplicates (i.e. multiple tasks
  // running on the same process represented by a single TaskGroup).
  base::flat_map<TaskId, raw_ptr<TaskGroup, CtnExperimental>>
      task_groups_by_task_id_;

  // A cached sorted list of the task IDs.
  mutable std::vector<TaskId> sorted_task_ids_;

  // The list of the task providers that are owned and observed by this task
  // manager implementation.
  std::vector<std::unique_ptr<TaskProvider>> task_providers_;

  // The current GPU memory usage stats that was last received from the
  // GpuDataManager.
  gpu::VideoMemoryUsageStats gpu_memory_stats_;

  // The specific blocking pool SequencedTaskRunner that will be used to make
  // sure TaskGroupSampler posts their refreshes serially.
  scoped_refptr<base::SequencedTaskRunner> blocking_pool_runner_;

  // A special sampler shared with all instances of TaskGroup that calculates a
  // subset of resources for all processes at once.
  scoped_refptr<SharedSampler> shared_sampler_;

#if BUILDFLAG(IS_CHROMEOS)
  // A sampler shared with all instances of TaskGroup that hold ARC tasks and
  // calculates memory footprint for all processes at once.
  std::unique_ptr<ArcSharedSampler> arc_shared_sampler_;
#endif  // BUILDFLAG(IS_CHROMEOS)

  // This will be set to true while there are observers and the task manager is
  // running.
  bool is_running_ = false;

  // This is set to true while waiting for a global memory dump from
  // memory_instrumentation.
  bool waiting_for_memory_dump_ = false;

  base::WeakPtrFactory<TaskManagerImpl> weak_ptr_factory_{this};
};

}  // namespace task_manager

#endif  // CHROME_BROWSER_TASK_MANAGER_SAMPLING_TASK_MANAGER_IMPL_H_