# Copyright 2021 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import contextlib
import json
import os
import pathlib
import socket

# Use a unix abstract domain socket:
# https://man7.org/linux/man-pages/man7/unix.7.html#:~:text=abstract:
SOCKET_ADDRESS = '\0chromium_build_server_socket'
BUILD_SERVER_ENV_VARIABLE = 'INVOKED_BY_BUILD_SERVER'


def MaybeRunCommand(name, argv, stamp_file, force):
  """Returns True if the command was successfully sent to the build server."""

  # When the build server runs a command, it sets this environment variable.
  # This prevents infinite recursion where the script sends a request to the
  # build server, then the build server runs the script, and then the script
  # sends another request to the build server.
  if BUILD_SERVER_ENV_VARIABLE in os.environ:
    return False
  with contextlib.closing(socket.socket(socket.AF_UNIX)) as sock:
    try:
      sock.connect(SOCKET_ADDRESS)
      sock.sendall(
          json.dumps({
              'name': name,
              'cmd': argv,
              'cwd': os.getcwd(),
              'stamp_file': stamp_file,
          }).encode('utf8'))
    except socket.error as e:
      # [Errno 111] Connection refused. Either the server has not been started
      #             or the server is not currently accepting new connections.
      if e.errno == 111:
        if force:
          raise RuntimeError(
              '\n\nBuild server is not running and '
              'android_static_analysis="build_server" is set.\nPlease run '
              'this command in a separate terminal:\n\n'
              '$ build/android/fast_local_dev_server.py\n\n') from None
        return False
      raise e

  # Siso needs the stamp file to be created in order for the build step to
  # complete. If the task fails when the build server runs it, the build server
  # will delete the stamp file so that it will be run again next build.
  pathlib.Path(stamp_file).touch()
  return True