# Copyright 2020 Google LLC
#
# 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
#
#      https://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,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import platform
import os
import subprocess
import sys


def normalize_path(p):
  if platform.system() == "Windows":
    # Sure. Good idea, bazel.
    return p.replace("\\", "/")
  return p


def write_platform(bazelrc):
  platform_config = "generic_clang"
  if platform.system() == "Windows":
    platform_config = "windows"
  print("build --config={}".format(platform_config), file=bazelrc)
  if not (platform.system() == "Darwin"):
    print("common --config={}".format("non_darwin"), file=bazelrc)


def write_python_bin(bazelrc):
  python_bin = normalize_path(sys.executable)
  print("build --python_path=\"{}\"".format(python_bin), file=bazelrc)
  # IREE extension compilation requires PYTHON_BIN
  print("build --action_env PYTHON_BIN=\"{}\"".format(python_bin), file=bazelrc)
  # TensorFlow defines this one. No idea why.
  print("build --action_env PYTHON_BIN_PATH=\"{}\"".format(python_bin),
        file=bazelrc)


def write_python_path(bazelrc):
  # For some reason, bazel doesn't always find the user site path, which
  # is typically where "pip install --user" libraries end up. Inject it.
  try:
    user_site = subprocess.run(
        [sys.executable, "-m", "site", "--user-site"],
        check=True,
        # TODO(#4131) python>=3.7: Use capture_output=True.
        stderr=subprocess.PIPE,
        stdout=subprocess.PIPE,
        # TODO(#4131) python>=3.7: Replace 'universal_newlines' with 'text'.
        universal_newlines=True,
    ).stdout.strip()
    print("Found user site directory:", user_site)
  except subprocess.CalledProcessError:
    print("Could not resolve user site directory")
    return
  print("build --action_env PYTHONPATH=\"{}\"".format(
      normalize_path(user_site)),
        file=bazelrc)


if len(sys.argv) > 1:
  local_bazelrc = sys.argv[1]
else:
  local_bazelrc = os.path.join(os.path.dirname(__file__), "configured.bazelrc")
with open(local_bazelrc, "wt") as bazelrc:
  write_platform(bazelrc)
  write_python_bin(bazelrc)
  write_python_path(bazelrc)

print("Wrote", local_bazelrc)