# Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
# for details. All rights reserved. Use of this source code is governed by a
# BSD-style license that can be found in the LICENSE file.

# This file contains a set of utilities functions used by other Python-based
# scripts.

import commands
import datetime
import json
import os
import platform
import re
import shutil
import subprocess
import tempfile
import sys

class Version(object):
  def __init__(self, channel, major, minor, patch, prerelease,
               prerelease_patch):
    self.channel = channel
    self.major = major
    self.minor = minor
    self.patch = patch
    self.prerelease = prerelease
    self.prerelease_patch = prerelease_patch

# Try to guess the host operating system.
def GuessOS():
  os_id = platform.system()
  if os_id == "Linux":
    return "linux"
  elif os_id == "Darwin":
    return "macos"
  elif os_id == "Windows" or os_id == "Microsoft":
    # On Windows Vista platform.system() can return "Microsoft" with some
    # versions of Python, see http://bugs.python.org/issue1082 for details.
    return "win32"
  elif os_id == 'FreeBSD':
    return 'freebsd'
  elif os_id == 'OpenBSD':
    return 'openbsd'
  elif os_id == 'SunOS':
    return 'solaris'
  else:
    return None


# Try to guess the host architecture.
def GuessArchitecture():
  os_id = platform.machine()
  if os_id.startswith('armv5te'):
    return 'armv5te'
  elif os_id.startswith('armv6'):
    return 'armv6'
  elif os_id.startswith('arm'):
    return 'arm'
  elif os_id.startswith('aarch64'):
    return 'arm64'
  elif os_id.startswith('mips'):
    return 'mips'
  elif '64' in os_id:
    return 'x64'
  elif (not os_id) or (not re.match('(x|i[3-6])86', os_id) is None):
    return 'ia32'
  elif os_id == 'i86pc':
    return 'ia32'
  else:
    guess_os = GuessOS()
    print "Warning: Guessing architecture %s based on os %s\n"\
          % (os_id, guess_os)
    if guess_os == 'win32':
      return 'ia32'
    return None


# Try to guess the number of cpus on this machine.
def GuessCpus():
  if os.getenv("DART_NUMBER_OF_CORES") is not None:
    return int(os.getenv("DART_NUMBER_OF_CORES"))
  if os.path.exists("/proc/cpuinfo"):
    return int(commands.getoutput("grep -E '^processor' /proc/cpuinfo | wc -l"))
  if os.path.exists("/usr/bin/hostinfo"):
    return int(commands.getoutput('/usr/bin/hostinfo |'
        ' grep "processors are logically available." |'
        ' awk "{ print \$1 }"'))
  win_cpu_count = os.getenv("NUMBER_OF_PROCESSORS")
  if win_cpu_count:
    return int(win_cpu_count)
  return 2

def GetWindowsRegistryKeyName(name):
  import win32process
  # Check if python process is 64-bit or if it's 32-bit running in 64-bit OS.
  # We need to know whether host is 64-bit so that we are looking in right
  # registry for Visual Studio path.
  if sys.maxsize > 2**32 or win32process.IsWow64Process():
    wow6432Node = 'Wow6432Node\\'
  else:
    wow6432Node = ''
  return r'SOFTWARE\%s%s' % (wow6432Node, name)

# Try to guess Visual Studio location when buiding on Windows.
def GuessVisualStudioPath():
  defaultPath = r"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7" \
                r"\IDE"
  defaultExecutable = "devenv.com"

  if not IsWindows():
    return defaultPath, defaultExecutable

  keyNamesAndExecutables = [
    # Pair for non-Express editions.
    (GetWindowsRegistryKeyName(r'Microsoft\VisualStudio'), 'devenv.com'),
    # Pair for 2012 Express edition.
    (GetWindowsRegistryKeyName(r'Microsoft\VSWinExpress'), 'VSWinExpress.exe'),
    # Pair for pre-2012 Express editions.
    (GetWindowsRegistryKeyName(r'Microsoft\VCExpress'), 'VCExpress.exe')]

  bestGuess = (0.0, (defaultPath, defaultExecutable))

  import _winreg
  for (keyName, executable) in keyNamesAndExecutables:
    try:
      key = _winreg.OpenKey(_winreg.HKEY_LOCAL_MACHINE, keyName)
    except WindowsError:
      # Can't find this key - moving on the next one.
      continue

    try:
      subkeyCounter = 0
      while True:
        try:
          subkeyName = _winreg.EnumKey(key, subkeyCounter)
          subkeyCounter += 1
        except WindowsError:
          # Reached end of enumeration. Moving on the next key.
          break

        match = re.match(r'^\d+\.\d+$', subkeyName)
        if match:
          with _winreg.OpenKey(key, subkeyName) as subkey:
            try:
              (installDir, registrytype) = _winreg.QueryValueEx(subkey,
                                                                'InstallDir')
            except WindowsError:
              # Can't find value under the key - continue to the next key.
              continue
            isExpress = executable != 'devenv.com'
            if not isExpress and subkeyName == '14.0':
              # Stop search since if we found non-Express VS2015 version
              # installed, which is preferred version.
              return installDir, executable
            else:
              version = float(subkeyName)
              # We prefer higher version of Visual Studio and given equal
              # version numbers we prefer non-Express edition.
              if version > bestGuess[0]:
                bestGuess = (version, (installDir, executable))
    finally:
      _winreg.CloseKey(key)
  return bestGuess[1]


# Returns true if we're running under Windows.
def IsWindows():
  return GuessOS() == 'win32'


# Reads a text file into an array of strings - one for each
# line. Strips comments in the process.
def ReadLinesFrom(name):
  result = []
  for line in open(name):
    if '#' in line:
      line = line[:line.find('#')]
    line = line.strip()
    if len(line) == 0:
      continue
    result.append(line)
  return result

# Filters out all arguments until the next '--' argument
# occurs.
def ListArgCallback(option, value, parser):
   if value is None:
     value = []

   for arg in parser.rargs:
     if arg[:2].startswith('--'):
       break
     value.append(arg)

   del parser.rargs[:len(value)]
   setattr(parser.values, option.dest, value)


# Filters out all argument until the first non '-' or the
# '--' argument occurs.
def ListDartArgCallback(option, value, parser):
   if value is None:
     value = []

   for arg in parser.rargs:
     if arg[:2].startswith('--') or arg[0] != '-':
       break
     value.append(arg)

   del parser.rargs[:len(value)]
   setattr(parser.values, option.dest, value)


# Mapping table between build mode and build configuration.
BUILD_MODES = {
  'debug': 'Debug',
  'release': 'Release',
  'product': 'Product',
}


# Mapping table between OS and build output location.
BUILD_ROOT = {
  'win32': os.path.join('out'),
  'linux': os.path.join('out'),
  'freebsd': os.path.join('out'),
  'macos': os.path.join('xcodebuild'),
}

ARCH_FAMILY = {
  'ia32': 'ia32',
  'x64': 'ia32',
  'arm': 'arm',
  'armv6': 'arm',
  'armv5te': 'arm',
  'arm64': 'arm',
  'mips': 'mips',
  'simarm': 'ia32',
  'simarmv6': 'ia32',
  'simarmv5te': 'ia32',
  'simmips': 'ia32',
  'simarm64': 'ia32',
  'simdbc': 'ia32',
  'simdbc64': 'ia32',
  'armsimdbc': 'arm',
}

ARCH_GUESS = GuessArchitecture()
BASE_DIR = os.path.abspath(os.path.join(os.curdir, '..'))
DART_DIR = os.path.abspath(os.path.join(__file__, '..', '..'))
VERSION_FILE = os.path.join(DART_DIR, 'tools', 'VERSION')

def GetBuildbotGSUtilPath():
  gsutil = '/b/build/scripts/slave/gsutil'
  if platform.system() == 'Windows':
    gsutil = 'e:\\\\b\\build\\scripts\\slave\\gsutil'
  return gsutil

def GetBuildMode(mode):
  return BUILD_MODES[mode]

def GetArchFamily(arch):
  return ARCH_FAMILY[arch]

def IsCrossBuild(target_os, arch):
  host_arch = ARCH_GUESS
  return ((GetArchFamily(host_arch) != GetArchFamily(arch)) or
          (target_os != GuessOS()))

def GetBuildConf(mode, arch, conf_os=None):
  if conf_os == 'android':
    return '%s%s%s' % (GetBuildMode(mode), conf_os.title(), arch.upper())
  else:
    # Ask for a cross build if the host and target architectures don't match.
    host_arch = ARCH_GUESS
    cross_build = ''
    if GetArchFamily(host_arch) != GetArchFamily(arch):
      print "GetBuildConf: Cross-build of %s on %s\n" % (arch, host_arch)
      cross_build = 'X'
    return '%s%s%s' % (GetBuildMode(mode), cross_build, arch.upper())

def GetBuildDir(host_os):
  return BUILD_ROOT[host_os]

def GetBuildRoot(host_os, mode=None, arch=None, target_os=None):
  build_root = GetBuildDir(host_os)
  if mode:
    build_root = os.path.join(build_root, GetBuildConf(mode, arch, target_os))
  return build_root

def GetBuildSdkBin(host_os, mode=None, arch=None, target_os=None):
  build_root = GetBuildRoot(host_os, mode, arch, target_os)
  return os.path.join(build_root, 'dart-sdk', 'bin')

def GetBaseDir():
  return BASE_DIR

def GetShortVersion():
  version = ReadVersionFile()
  return ('%s.%s.%s.%s.%s' % (
      version.major, version.minor, version.patch, version.prerelease,
      version.prerelease_patch))

def GetSemanticSDKVersion(ignore_svn_revision=False):
  version = ReadVersionFile()
  if not version:
    return None

  if version.channel == 'be':
    postfix = '-edge' if ignore_svn_revision else '-edge.%s' % GetGitRevision()
  elif version.channel == 'dev':
    postfix = '-dev.%s.%s' % (version.prerelease, version.prerelease_patch)
  else:
    assert version.channel == 'stable'
    postfix = ''

  return '%s.%s.%s%s' % (version.major, version.minor, version.patch, postfix)

def GetVersion():
  return GetSemanticSDKVersion()

# The editor used to produce the VERSION file put on gcs. We now produce this
# in the bots archiving the sdk.
# The content looks like this:
#{
#  "date": "2015-05-28",
#  "version": "1.11.0-edge.131653",
#  "revision": "535394c2657ede445142d8a92486d3899bbf49b5"
#}
def GetVersionFileContent():
  result = {"date": str(datetime.date.today()),
            "version": GetVersion(),
            "revision": GetGitRevision()}
  return json.dumps(result, indent=2)

def GetChannel():
  version = ReadVersionFile()
  return version.channel

def GetUserName():
  key = 'USER'
  if sys.platform == 'win32':
    key = 'USERNAME'
  return os.environ.get(key, '')

def ReadVersionFile():
  def match_against(pattern, file_content):
    match = re.search(pattern, file_content, flags=re.MULTILINE)
    if match:
      return match.group(1)
    return None

  try:
    fd = open(VERSION_FILE)
    content = fd.read()
    fd.close()
  except:
    print "Warning: Couldn't read VERSION file (%s)" % VERSION_FILE
    return None

  channel = match_against('^CHANNEL ([A-Za-z0-9]+)$', content)
  major = match_against('^MAJOR (\d+)$', content)
  minor = match_against('^MINOR (\d+)$', content)
  patch = match_against('^PATCH (\d+)$', content)
  prerelease = match_against('^PRERELEASE (\d+)$', content)
  prerelease_patch = match_against('^PRERELEASE_PATCH (\d+)$', content)

  if channel and major and minor and prerelease and prerelease_patch:
    return Version(
        channel, major, minor, patch, prerelease, prerelease_patch)
  else:
    print "Warning: VERSION file (%s) has wrong format" % VERSION_FILE
    return None


# Our schema for releases and archiving is based on an increasing
# sequence of numbers. In the svn world this was simply the revision of a
# commit, which would always give us a one to one mapping between the number
# and the commit. This was true across branches as well, so a number used
# to archive a build was always unique and unambiguous.
# In git there is no such global number, so we loosen the requirement a bit.
# We only use numbers on the master branch (bleeding edge). On branches
# we use the version number instead for archiving purposes.
# The number on master is the count of commits on the master branch.
def GetArchiveVersion():
  version = ReadVersionFile()
  if not version:
    raise 'Could not get the archive version, parsing the version file failed'
  if version.channel == 'be':
    return GetGitNumber()
  return GetSemanticSDKVersion()


def GetGitRevision():
  # When building from tarball use tools/GIT_REVISION
  git_revision_file = os.path.join(DART_DIR, 'tools', 'GIT_REVISION')
  try:
    with open(git_revision_file) as fd:
      return fd.read()
  except:
    pass

  p = subprocess.Popen(['git', 'log', '-n', '1', '--pretty=format:%H'],
                       stdout = subprocess.PIPE,
                       stderr = subprocess.STDOUT, shell=IsWindows(),
                       cwd = DART_DIR)
  output, _ = p.communicate()
  # We expect a full git hash
  if len(output) != 40:
    print "Warning: could not parse git commit, output was %s" % output
    return None
  return output

# To eliminate clashing with older archived builds on bleeding edge we add
# a base number bigger the largest svn revision (this also gives us an easy
# way of seeing if an archive comes from git based or svn based commits).
GIT_NUMBER_BASE = 100000
def GetGitNumber():
  p = subprocess.Popen(['git', 'rev-list', 'HEAD', '--count'],
                       stdout = subprocess.PIPE,
                       stderr = subprocess.STDOUT, shell=IsWindows(),
                       cwd = DART_DIR)
  output, _ = p.communicate()
  try:
    number = int(output)
    return number + GIT_NUMBER_BASE
  except:
    print "Warning: could not parse git count, output was %s" % output
  return None

def ParseGitInfoOutput(output):
  """Given a git log, determine the latest corresponding svn revision."""
  for line in output.split('\n'):
    tokens = line.split()
    if len(tokens) > 0 and tokens[0] == 'git-svn-id:':
      return tokens[1].split('@')[1]
  return None

def ParseSvnInfoOutput(output):
  revision_match = re.search('Last Changed Rev: (\d+)', output)
  if revision_match:
    return revision_match.group(1)
  return None

def RewritePathSeparator(path, workspace):
  # Paths in test files are always specified using '/'
  # as the path separator. Replace with the actual
  # path separator before use.
  if '/' in path:
    split_path = path.split('/')
    path = os.sep.join(split_path)
    path = os.path.join(workspace, path)
    if not os.path.exists(path):
      raise Exception(path)
  return path


def ParseTestOptions(pattern, source, workspace):
  match = pattern.search(source)
  if match:
    return [RewritePathSeparator(o, workspace) for o in match.group(1).split(' ')]
  else:
    return None


def ParseTestOptionsMultiple(pattern, source, workspace):
  matches = pattern.findall(source)
  if matches:
    result = []
    for match in matches:
      if len(match) > 0:
        result.append(
            [RewritePathSeparator(o, workspace) for o in match.split(' ')])
      else:
        result.append([])
    return result
  else:
    return None


def ConfigureJava():
  java_home = '/usr/libexec/java_home'
  if os.path.exists(java_home):
    proc = subprocess.Popen([java_home, '-v', '1.6+'],
                            stdout=subprocess.PIPE,
                            stderr=subprocess.PIPE)
    (stdout, stderr) = proc.communicate()
    if proc.wait() != 0:
      return None
    new = stdout.strip()
    current = os.getenv('JAVA_HOME', new)
    if current != new:
      sys.stderr.write('Please set JAVA_HOME to %s\n' % new)
      os.putenv('JAVA_HOME', new)


def Daemonize():
  """
  Create a detached background process (daemon). Returns True for
  the daemon, False for the parent process.
  See: http://www.faqs.org/faqs/unix-faq/programmer/faq/
  "1.7 How do I get my program to act like a daemon?"
  """
  if os.fork() > 0:
    return False
  os.setsid()
  if os.fork() > 0:
    exit(0)
    raise
  return True


def PrintError(string):
  """Writes and flushes a string to stderr."""
  sys.stderr.write(string)
  sys.stderr.write('\n')


def CheckedUnlink(name):
  """Unlink a file without throwing an exception."""
  try:
    os.unlink(name)
  except OSError, e:
    PrintError("os.unlink() " + str(e))


def Main():
  print "GuessOS() -> ", GuessOS()
  print "GuessArchitecture() -> ", GuessArchitecture()
  print "GuessCpus() -> ", GuessCpus()
  print "IsWindows() -> ", IsWindows()
  print "GuessVisualStudioPath() -> ", GuessVisualStudioPath()
  print "GetGitRevision() -> ", GetGitRevision()
  print "GetVersionFileContent() -> ", GetVersionFileContent()
  print "GetGitNumber() -> ", GetGitNumber()

class Error(Exception):
  pass


class ToolError(Exception):
  """Deprecated exception, use Error instead."""

  def __init__(self, value):
    self.value = value

  def __str__(self):
    return repr(self.value)


def IsCrashExitCode(exit_code):
  if IsWindows():
    return 0x80000000 & exit_code
  else:
    return exit_code < 0


def DiagnoseExitCode(exit_code, command):
  if IsCrashExitCode(exit_code):
    sys.stderr.write('Command: %s\nCRASHED with exit code %d (0x%x)\n' % (
        ' '.join(command), exit_code, exit_code & 0xffffffff))


def Touch(name):
  with file(name, 'a'):
    os.utime(name, None)


def ExecuteCommand(cmd):
  """Execute a command in a subprocess."""
  print 'Executing: ' + ' '.join(cmd)
  pipe = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE,
      shell=IsWindows())
  output = pipe.communicate()
  if pipe.returncode != 0:
    raise Exception('Execution failed: ' + str(output))
  return pipe.returncode, output


# The checked-in SDKs are documented at
#     https://github.com/dart-lang/sdk/wiki/The-checked-in-SDK-in-tools
def CheckedInSdkPath():
  # We don't use the normal macos, linux, win32 directory names here, instead,
  # we use the names that the download_from_google_storage script uses.
  osdict = {'Darwin':'mac', 'Linux':'linux', 'Windows':'win'}
  system = platform.system()
  try:
    osname = osdict[system]
  except KeyError:
    print >>sys.stderr, ('WARNING: platform "%s" not supported') % (system)
    return None;
  tools_dir = os.path.dirname(os.path.realpath(__file__))
  return os.path.join(tools_dir,
                      'sdks',
                      osname,
                      'dart-sdk')


def CheckedInSdkExecutable():
  name = 'dart'
  if IsWindows():
    name = 'dart.exe'
  elif GuessOS() == 'linux':
    arch = GuessArchitecture()
    if arch == 'mips':
      name = 'dart-mips'
    elif arch == 'arm':
      name = 'dart-arm'
    elif arch == 'arm64':
      name = 'dart-arm64'
    elif arch == 'armv5te':
      # TODO(zra): This binary does not exist, yet. Check one in once we have
      # sufficient stability.
      name = 'dart-armv5te'
    elif arch == 'armv6':
      # TODO(zra): Ditto.
      name = 'dart-armv6'
  return os.path.join(CheckedInSdkPath(), 'bin', name)


def CheckedInSdkCheckExecutable():
  executable = CheckedInSdkExecutable()
  canary_script = os.path.join(os.path.dirname(os.path.realpath(__file__)),
                               'canary.dart')
  try:
    with open(os.devnull, 'wb') as silent_sink:
      if 0 == subprocess.call([executable, canary_script], stdout=silent_sink):
        return True
  except OSError as e:
    pass
  return False


class TempDir(object):
  def __init__(self, prefix=''):
    self._temp_dir = None
    self._prefix = prefix

  def __enter__(self):
    self._temp_dir = tempfile.mkdtemp(self._prefix)
    return self._temp_dir

  def __exit__(self, *_):
    shutil.rmtree(self._temp_dir, ignore_errors=True)

class ChangedWorkingDirectory(object):
  def __init__(self, working_directory):
    self._working_directory = working_directory

  def __enter__(self):
    self._old_cwd = os.getcwd()
    print "Enter directory = ", self._working_directory
    os.chdir(self._working_directory)

  def __exit__(self, *_):
    print "Enter directory = ", self._old_cwd
    os.chdir(self._old_cwd)


if __name__ == "__main__":
  import sys
  Main()