# Copyright 2025 The CLU Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
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"""Methods for running triggering a profiler for accelerators.

Where results are stored depends on the platform (e.g. TensorBoard).
"""
from collections.abc import Callable, Sequence
import threading
from typing import Optional, Protocol

from absl import logging

import jax



def start(logdir: str, options=None):
  """Starts profiling."""
  if options is not None:
    raise NotImplementedError(
        "'options' not supported by clu.profiler.start(). Please file an issue "
        "at https://github.com/google/jax/issues requesting profiler option "
        "support if you need this feature.")
  if logdir is None:
    raise ValueError("Must specify logdir where profile should be written!")
  jax.profiler.start_trace(logdir)


def stop() -> Optional[str]:
  """Stops profiling."""
  jax.profiler.stop_trace()


CollectCallback = Callable[[Optional[str]], None]


def collect(logdir: str,
            callback: CollectCallback,
            hosts: Optional[Sequence[str]] = None,
            duration_ms: int = 3_000):
  """Calls start() followed by stop() after specified duration."""
  del hosts  # not used.
  start(logdir)

  def timer_cb():
    stop()
    callback(None)

  threading.Timer(duration_ms / 1e3, timer_cb).start()