# Copyright 2014 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

from __future__ import print_function

import argparse
import doctest
import itertools
import os
import plistlib
import re
import subprocess
import sys

# src directory
ROOT_SRC_DIR = os.path.dirname(
    os.path.dirname(
        os.path.dirname(os.path.dirname(os.path.realpath(__file__)))))


# This script prints information about the build system, the operating
# system and the iOS or Mac SDK (depending on the platform "iphonesimulator",
# "iphoneos" or "macosx" generally).

def SplitVersion(version):
  """Splits the Xcode version to 3 values.

  >>> list(SplitVersion('8.2.1.1'))
  ['8', '2', '1']
  >>> list(SplitVersion('9.3'))
  ['9', '3', '0']
  >>> list(SplitVersion('10.0'))
  ['10', '0', '0']
  """
  version = version.split('.')
  return itertools.islice(itertools.chain(version, itertools.repeat('0')), 0, 3)

def FormatVersion(version):
  """Converts Xcode version to a format required for DTXcode in Info.plist

  >>> FormatVersion('8.2.1')
  '0821'
  >>> FormatVersion('9.3')
  '0930'
  >>> FormatVersion('10.0')
  '1000'
  """
  major, minor, patch = SplitVersion(version)
  return ('%2s%s%s' % (major, minor, patch)).replace(' ', '0')

def FillXcodeVersion(settings, developer_dir):
  """Fills the Xcode version and build number into |settings|."""
  if developer_dir:
    xcode_version_plist_path = os.path.join(
        developer_dir, 'Contents/version.plist')
    version_plist = plistlib.readPlist(xcode_version_plist_path)
    settings['xcode_version'] = FormatVersion(
        version_plist['CFBundleShortVersionString'])
    settings['xcode_version_int'] = int(settings['xcode_version'], 10)
    settings['xcode_build'] = version_plist['ProductBuildVersion']
    return

  lines = subprocess.check_output(['xcodebuild', '-version']).splitlines()
  settings['xcode_version'] = FormatVersion(lines[0].split()[-1])
  settings['xcode_version_int'] = int(settings['xcode_version'], 10)
  settings['xcode_build'] = lines[-1].split()[-1]


def FillMachineOSBuild(settings):
  """Fills OS build number into |settings|."""
  machine_os_build = subprocess.check_output(['sw_vers', '-buildVersion'],
                                             universal_newlines=True).strip()
  settings['machine_os_build'] = machine_os_build

  # The reported build number is made up from the kernel major version number,
  # a minor version represented as a letter, a build number, and an optional
  # packaging version.
  #
  # For example, the macOS 10.15.3 GM build is 19D76.
  # - 19 is the Darwin kernel that ships with 10.15.
  # - D is minor version 4. 10.15.0 builds had minor version 1.
  # - 76 is the build number. 75 other builds were stamped before GM came out.
  #
  # The macOS 10.15.4 beta 5 build is 19E258a. The trailing "a" means the same
  # build output was packaged twice.
  build_match = re.match(r'^(\d+)([A-Z])(\d+)([a-z]?)$', machine_os_build)
  assert build_match, "Unexpected macOS build format: %r" % machine_os_build
  settings['machine_os_build_major'] = int(build_match.group(1), 10)


def FillSDKPathAndVersion(settings, platform, xcode_version):
  """Fills the SDK path and version for |platform| into |settings|."""
  settings['sdk_path'] = subprocess.check_output([
      'xcrun', '-sdk', platform, '--show-sdk-path']).strip()
  settings['sdk_version'] = subprocess.check_output([
      'xcrun', '-sdk', platform, '--show-sdk-version']).strip()
  settings['sdk_platform_path'] = subprocess.check_output([
      'xcrun', '-sdk', platform, '--show-sdk-platform-path']).strip()
  settings['sdk_build'] = subprocess.check_output(
      ['xcrun', '-sdk', platform, '--show-sdk-build-version']).strip()


def CreateXcodeSymlinkAt(src, dst):
  """Create symlink to Xcode directory at target location."""

  if not os.path.isdir(dst):
    os.makedirs(dst)

  dst = os.path.join(dst, os.path.basename(src))
  updated_value = '//' + os.path.relpath(dst, ROOT_SRC_DIR)

  # Update the symlink only if it is different from the current destination.
  if os.path.islink(dst):
    current_src = os.readlink(dst)
    if current_src == src:
      return updated_value
    os.unlink(dst)
    sys.stderr.write('existing symlink %s points %s; want %s. Removed.' %
                     (dst, current_src, src))
  os.symlink(src, dst)
  return updated_value


if __name__ == '__main__':
  doctest.testmod()

  parser = argparse.ArgumentParser()
  parser.add_argument("--developer_dir", dest="developer_dir", required=False)
  parser.add_argument("--get_sdk_info",
                    action="store_true", dest="get_sdk_info", default=False,
                    help="Returns SDK info in addition to xcode/machine info.")
  parser.add_argument(
      "--create_symlink_at",
      action="store",
      dest="create_symlink_at",
      help="Create symlink of SDK at given location and "
      "returns the symlinked paths as SDK info instead "
      "of the original location.")
  args, unknownargs = parser.parse_known_args()
  if args.developer_dir:
    os.environ['DEVELOPER_DIR'] = args.developer_dir

  if len(unknownargs) != 1:
    sys.stderr.write(
        'usage: %s [iphoneos|iphonesimulator|macosx]\n' %
        os.path.basename(sys.argv[0]))
    sys.exit(1)

  settings = {}
  FillMachineOSBuild(settings)
  FillXcodeVersion(settings, args.developer_dir)
  if args.get_sdk_info:
    FillSDKPathAndVersion(settings, unknownargs[0], settings['xcode_version'])

  for key in sorted(settings):
    value = settings[key]
    if args.create_symlink_at and '_path' in key:
      value = CreateXcodeSymlinkAt(value, args.create_symlink_at)
    if isinstance(value, str):
      value = '"%s"' % value
    print('%s=%s' % (key, value))