#!/usr/bin/env python
# Copyright (C) 2017 The Android Open Source Project
#
# 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,
# 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 argparse
import hashlib
import logging
import os
import shutil
import subprocess
import sys
import urllib
import zipfile

PREBUILTS = (
  # GN
  ('buildtools/mac/gn',
   'https://storage.googleapis.com/chromium-gn/c2c934d4dda1f470a6511b1015dda9a9fb1ce50b',
   'c2c934d4dda1f470a6511b1015dda9a9fb1ce50b',
   'darwin'
  ),
  ('buildtools/linux64/gn',
   'https://storage.googleapis.com/chromium-gn/b53fa13e950948c6f9a062189b76b34a9610281f',
   'b53fa13e950948c6f9a062189b76b34a9610281f',
   'linux2'
  ),

  # Ninja
  ('buildtools/mac/ninja',
   'https://storage.googleapis.com/fuchsia-build/fuchsia/ninja/mac/a1db595e824c50cf565fbf0af2437fd91b7babf4',
   'a1db595e824c50cf565fbf0af2437fd91b7babf4',
   'darwin'
  ),
  ('buildtools/linux64/ninja',
   'https://storage.googleapis.com/fuchsia-build/fuchsia/ninja/linux64/d35b36c84a09f7e38b25947cafada10e8bf835bc',
   'd35b36c84a09f7e38b25947cafada10e8bf835bc',
   'linux2'
  ),

  # Android NDK
  ('buildtools/ndk.zip',
   'https://dl.google.com/android/repository/android-ndk-r15c-darwin-x86_64.zip',
   'ea4b5d76475db84745aa8828000d009625fc1f98',
   'darwin'
  ),
  ('buildtools/ndk.zip',
   'https://dl.google.com/android/repository/android-ndk-r15c-linux-x86_64.zip',
   '0bf02d4e8b85fd770fd7b9b2cdec57f9441f27a2',
   'linux2'
  ),

  # Keep in sync with Android's //external/googletest/README.version .
  ('buildtools/googletest.zip',
   'https://github.com/google/googletest/archive/ff07a5de0e81580547f1685e101194ed1a4fcd56.zip',
   'c7edec7d7e6db1fc37a20710de9c4d89e3a3893b',
   'all'
  ),

  # Keep in sync with Android's //external/protobuf/README.version .
  ('buildtools/protobuf.zip',
   'https://github.com/google/protobuf/releases/download/v3.0.0-beta-3/protobuf-cpp-3.0.0-beta-3.zip',
   '3caec60aa9d8eefc8c3c3201b6b8ca19935edb89',
   'all'
  ),

  # libc++ and libc++abi, for clang msan that require rebuilding the C++ lib
  # from sources. Keep the SHA1s in sync with Chrome's src/buildtools/DEPS .
  ('buildtools/libcxx',
   'https://chromium.googlesource.com/chromium/llvm-project/libcxx.git',
   '3a07dd740be63878167a0ea19fe81869954badd7',
   'all'
  ),
  ('buildtools/libcxxabi',
   'https://chromium.googlesource.com/chromium/llvm-project/libcxxabi.git',
   '4072e8fd76febee37f60aeda76d6d9f5e3791daa',
   'all'
  ),


)

ROOT_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))


def ReadFile(path):
  if not os.path.exists(path):
    return None
  with open(path) as f:
      return f.read().strip()


def MkdirRecursive(path):
  # Works with both relative and absolute paths
  cwd = '/' if path.startswith('/') else ROOT_DIR
  for part in path.split('/'):
    cwd = os.path.join(cwd, part)
    if not os.path.exists(cwd):
      os.makedirs(cwd)
    else:
      assert(os.path.isdir(cwd))


def HashLocalFile(path):
  if not os.path.exists(path):
    return None
  with open(path, 'rb') as f:
    return hashlib.sha1(f.read()).hexdigest()


def ExtractZipfilePreservePermissions(zf, info, path):
  zf.extract(info.filename, path=path)
  target_path = os.path.join(path, info.filename)
  min_acls = 0o755 if info.filename.endswith('/') else 0o644
  os.chmod(target_path, (info.external_attr >> 16L) | min_acls)


def IsGitRepoCheckoutOutAtRevision(path, revision):
  return ReadFile(os.path.join(path, '.git', 'HEAD')) == revision


def CheckoutGitRepo(path, git_url, revision):
  if IsGitRepoCheckoutOutAtRevision(path, revision):
    return
  if os.path.exists(path):
    shutil.rmtree(path)
  MkdirRecursive(path)
  logging.info('Fetching %s @ %s into %s', git_url, revision, path)
  subprocess.check_call(['git', 'clone', git_url, path], cwd=path)
  subprocess.check_call(['git', 'checkout', revision, '--quiet'], cwd=path)
  assert(IsGitRepoCheckoutOutAtRevision(path, revision))


def Main():
  parser = argparse.ArgumentParser()
  parser.add_argument('--skip', action='append', default=[])
  args = parser.parse_args()
  skip_set = set(args.skip)
  for rel_path, url, expected_sha1, platform in PREBUILTS:
    if platform != 'all' and platform != sys.platform:
      continue
    if os.path.basename(rel_path) in skip_set:
      logging.info('Skipping %s because of --skip cmdline arg', rel_path)
      continue
    local_path = os.path.join(ROOT_DIR, rel_path)
    if url.endswith('.git'):
      CheckoutGitRepo(local_path, url, expected_sha1)
      continue
    is_zip = local_path.lower().endswith('.zip')
    zip_target_dir = local_path[:-4] if is_zip else None
    zip_dir_stamp = os.path.join(zip_target_dir, '.stamp') if is_zip else None

    if ((not is_zip and HashLocalFile(local_path) == expected_sha1) or
        (is_zip and ReadFile(zip_dir_stamp) == expected_sha1)):
      continue
    MkdirRecursive(os.path.dirname(rel_path))
    if HashLocalFile(local_path) != expected_sha1:
      download_path = local_path + '.tmp'
      logging.info('Downloading %s from %s', local_path, url)
      urllib.urlretrieve(url, download_path)
      os.chmod(download_path, 0o755)
      if (HashLocalFile(download_path) != expected_sha1):
        os.remove(download_path)
        logging.fatal('SHA1 mismatch for %s', download_path)
        return 1
      os.rename(download_path, local_path)
    assert(HashLocalFile(local_path) == expected_sha1)

    if is_zip:
      logging.info('Extracting %s into %s' % (local_path, zip_target_dir))
      assert(os.path.commonprefix((ROOT_DIR, zip_target_dir)) == ROOT_DIR)
      if os.path.exists(zip_target_dir):
        logging.info('Deleting stale dir %s' % zip_target_dir)
        shutil.rmtree(zip_target_dir)
      with zipfile.ZipFile(local_path, 'r') as zf:
        for info in zf.infolist():
          ExtractZipfilePreservePermissions(zf, info, zip_target_dir)

        # If the zip contains one root folder, rebase one level up moving all
        # its sub files and folders inside |target_dir|.
        subdir = os.listdir(zip_target_dir)
        if len(subdir) == 1:
          subdir = os.path.join(zip_target_dir, subdir[0])
          if os.path.isdir(subdir):
            for subf in os.listdir(subdir):
              shutil.move(os.path.join(subdir,subf), zip_target_dir)
            os.rmdir(subdir)
        with open(zip_dir_stamp, 'w') as stamp_file:
          stamp_file.write(expected_sha1)
        os.remove(local_path)


if __name__ == '__main__':
  logging.basicConfig(level=logging.INFO)
  sys.exit(Main())