#!/usr/bin/env python
# Copyright 2017 The Dart project authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Pulls down tools required to build Dart."""

import errno
import os
import platform
import subprocess
import sys

THIS_DIR = os.path.abspath(os.path.dirname(__file__))
DART_ROOT = os.path.abspath(os.path.join(THIS_DIR, '..', '..'))
BUILDTOOLS = os.path.join(DART_ROOT, 'buildtools')
TOOLS_BUILDTOOLS = os.path.join(DART_ROOT, 'tools', 'buildtools')

sys.path.insert(0, os.path.join(DART_ROOT, 'tools'))
import find_depot_tools

DEPOT_PATH = find_depot_tools.add_depot_tools_to_path()


def UpdateClangFormatOnWindows():
  sha1_file = os.path.join(TOOLS_BUILDTOOLS, 'win', 'clang-format.exe.sha1')
  output_dir = os.path.join(BUILDTOOLS, 'win', 'clang-format.exe')
  downloader_script = os.path.join(
      DEPOT_PATH, 'download_from_google_storage.py')
  download_cmd = [
    'python',
    downloader_script,
    '--no_auth',
    '--no_resume',
    '--quiet',
    '--platform=win',
    '--bucket',
    'chromium-clang-format',
    '-s',
    sha1_file,
    '-o',
    output_dir
  ]
  return subprocess.call(download_cmd)


def CreateSymlink(symlink, link_name):
  try:
    os.symlink(symlink, link_name)
  except OSError, e:
    if e.errno == errno.EEXIST:
      os.remove(link_name)
      os.symlink(symlink, link_name)
    else:
      raise e


# On Mac and Linux we symlink clang-format and gn to the place where
# 'git cl format' expects them to be.
def LinksForGitCLFormat():
  if sys.platform == 'darwin':
    platform = 'darwin'
    tools = 'mac'
    toolchain = 'mac-x64'
  elif sys.platform.startswith('linux'):
    platform = 'linux'
    tools = 'linux64'
    toolchain = 'linux-x64'
  else:
    print 'Unknown platform: ' + sys.platform
    return 1

  clang_format = os.path.join(
      BUILDTOOLS, toolchain, 'clang', 'bin', 'clang-format')
  gn = os.path.join(BUILDTOOLS, 'gn')
  dest_dir = os.path.join(BUILDTOOLS, tools)
  if not os.path.exists(dest_dir):
    os.makedirs(dest_dir)
  clang_format_dest = os.path.join(dest_dir, 'clang-format')
  gn_dest = os.path.join(dest_dir, 'gn')
  CreateSymlink(clang_format, clang_format_dest)
  CreateSymlink(gn, gn_dest)
  return 0


def main(argv):
  arch_id = platform.machine()
  # Don't try to download binaries if we're on an arm machine.
  if arch_id.startswith('arm') or arch_id.startswith('aarch64'):
    print('Not downloading buildtools binaries for ' + arch_id)
    return 0
  if sys.platform.startswith('win'):
    return UpdateClangFormatOnWindows()
  return LinksForGitCLFormat()


if __name__ == '__main__':
  sys.exit(main(sys.argv))