// Copyright 2015 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 COMPONENTS_SCHEDULER_CHILD_SCHEDULER_TASK_RUNNER_DELEGATE_H_
#define COMPONENTS_SCHEDULER_CHILD_SCHEDULER_TASK_RUNNER_DELEGATE_H_

#include "base/message_loop/message_loop.h"
#include "components/scheduler/child/nestable_single_thread_task_runner.h"
#include "components/scheduler/scheduler_export.h"

namespace scheduler {

class SCHEDULER_EXPORT SchedulerTaskRunnerDelegate
    : public NestableSingleThreadTaskRunner {
 public:
  SchedulerTaskRunnerDelegate() {}

  // If the underlying task runner supports the concept of a default task
  // runner, the delegate should implement this function to redirect that task
  // runner to the scheduler.
  virtual void SetDefaultTaskRunner(
      scoped_refptr<base::SingleThreadTaskRunner> task_runner) = 0;

  // Similarly this method can be used to restore the original task runner when
  // the scheduler no longer wants to intercept tasks.
  virtual void RestoreDefaultTaskRunner() = 0;

 protected:
  ~SchedulerTaskRunnerDelegate() override {}

  DISALLOW_COPY_AND_ASSIGN(SchedulerTaskRunnerDelegate);
};

}  // namespace scheduler

#endif  // COMPONENTS_SCHEDULER_CHILD_SCHEDULER_TASK_RUNNER_DELEGATE_H_