# Copyright (c) 2012 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.

"""Top-level presubmit script for Chromium.

See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
for more details about the presubmit API built into gcl.
"""


import re


_EXCLUDED_PATHS = (
    r"^breakpad[\\\/].*",
    r"^native_client_sdk[\\\/].*",
    r"^net[\\\/]tools[\\\/]spdyshark[\\\/].*",
    r"^skia[\\\/].*",
    r"^v8[\\\/].*",
    r".*MakeFile$",
)


_TEST_ONLY_WARNING = (
    'You might be calling functions intended only for testing from\n'
    'production code.  It is OK to ignore this warning if you know what\n'
    'you are doing, as the heuristics used to detect the situation are\n'
    'not perfect.  The commit queue will not block on this warning.\n'
    'Email joi@chromium.org if you have questions.')



def _CheckNoInterfacesInBase(input_api, output_api):
  """Checks to make sure no files in libbase.a have |@interface|."""
  pattern = input_api.re.compile(r'^\s*@interface', input_api.re.MULTILINE)
  files = []
  for f in input_api.AffectedSourceFiles(input_api.FilterSourceFile):
    if (f.LocalPath().startswith('base/') and
        not f.LocalPath().endswith('_unittest.mm')):
      contents = input_api.ReadFile(f)
      if pattern.search(contents):
        files.append(f)

  if len(files):
    return [ output_api.PresubmitError(
        'Objective-C interfaces or categories are forbidden in libbase. ' +
        'See http://groups.google.com/a/chromium.org/group/chromium-dev/' +
        'browse_thread/thread/efb28c10435987fd',
        files) ]
  return []


def _CheckNoProductionCodeUsingTestOnlyFunctions(input_api, output_api):
  """Attempts to prevent use of functions intended only for testing in
  non-testing code. For now this is just a best-effort implementation
  that ignores header files and may have some false positives. A
  better implementation would probably need a proper C++ parser.
  """
  # We only scan .cc files and the like, as the declaration of
  # for-testing functions in header files are hard to distinguish from
  # calls to such functions without a proper C++ parser.
  source_extensions = r'\.(cc|cpp|cxx|mm)$'
  file_inclusion_pattern = r'.+%s' % source_extensions
  file_exclusion_patterns = (
      r'.*/(test_|mock_).+%s' % source_extensions,
      r'.+_test_(support|base)%s' % source_extensions,
      r'.+_(api|browser|perf|unit|ui)?test%s' % source_extensions,
      r'.+profile_sync_service_harness%s' % source_extensions,
      )
  path_exclusion_patterns = (
      r'.*[/\\](test|tool(s)?)[/\\].*',
      # At request of folks maintaining this folder.
      r'chrome[/\\]browser[/\\]automation[/\\].*',
      )

  base_function_pattern = r'ForTest(ing)?|for_test(ing)?'
  inclusion_pattern = input_api.re.compile(r'(%s)\s*\(' % base_function_pattern)
  exclusion_pattern = input_api.re.compile(
    r'::[A-Za-z0-9_]+(%s)|(%s)[^;]+\{' % (
      base_function_pattern, base_function_pattern))

  def FilterFile(affected_file):
    black_list = (file_exclusion_patterns + path_exclusion_patterns +
                  _EXCLUDED_PATHS + input_api.DEFAULT_BLACK_LIST)
    return input_api.FilterSourceFile(
      affected_file,
      white_list=(file_inclusion_pattern, ),
      black_list=black_list)

  problems = []
  for f in input_api.AffectedSourceFiles(FilterFile):
    local_path = f.LocalPath()
    lines = input_api.ReadFile(f).splitlines()
    line_number = 0
    for line in lines:
      if (inclusion_pattern.search(line) and
          not exclusion_pattern.search(line)):
        problems.append(
          '%s:%d\n    %s' % (local_path, line_number, line.strip()))
      line_number += 1

  if problems:
    if not input_api.is_committing:
      return [output_api.PresubmitPromptWarning(_TEST_ONLY_WARNING, problems)]
    else:
      # We don't warn on commit, to avoid stopping commits going through CQ.
      return [output_api.PresubmitNotifyResult(_TEST_ONLY_WARNING, problems)]
  else:
    return []


def _CheckNoIOStreamInHeaders(input_api, output_api):
  """Checks to make sure no .h files include <iostream>."""
  files = []
  pattern = input_api.re.compile(r'^#include\s*<iostream>',
                                 input_api.re.MULTILINE)
  for f in input_api.AffectedSourceFiles(input_api.FilterSourceFile):
    if not f.LocalPath().endswith('.h'):
      continue
    contents = input_api.ReadFile(f)
    if pattern.search(contents):
      files.append(f)

  if len(files):
    return [ output_api.PresubmitError(
        'Do not #include <iostream> in header files, since it inserts static ' +
        'initialization into every file including the header. Instead, ' +
        '#include <ostream>. See http://crbug.com/94794',
        files) ]
  return []


def _CheckNoNewWStrings(input_api, output_api):
  """Checks to make sure we don't introduce use of wstrings."""
  problems = []
  for f in input_api.AffectedFiles():
    if (not f.LocalPath().endswith(('.cc', '.h')) or
        f.LocalPath().endswith('test.cc')):
      continue

    for line_num, line in f.ChangedContents():
      if 'wstring' in line:
        problems.append('    %s:%d' % (f.LocalPath(), line_num))

  if not problems:
    return []
  return [output_api.PresubmitPromptWarning('New code should not use wstrings.'
      '  If you are calling an API that accepts a wstring, fix the API.\n' +
      '\n'.join(problems))]


def _CheckNoDEPSGIT(input_api, output_api):
  """Make sure .DEPS.git is never modified manually."""
  if any(f.LocalPath().endswith('.DEPS.git') for f in
      input_api.AffectedFiles()):
    return [output_api.PresubmitError(
      'Never commit changes to .DEPS.git. This file is maintained by an\n'
      'automated system based on what\'s in DEPS and your changes will be\n'
      'overwritten.\n'
      'See http://code.google.com/p/chromium/wiki/UsingNewGit#Rolling_DEPS\n'
      'for more information')]
  return []


def _CheckNoFRIEND_TEST(input_api, output_api):
  """Make sure that gtest's FRIEND_TEST() macro is not used, the
  FRIEND_TEST_ALL_PREFIXES() macro from base/gtest_prod_util.h should be used
  instead since that allows for FLAKY_, FAILS_ and DISABLED_ prefixes."""
  problems = []

  file_filter = lambda f: f.LocalPath().endswith(('.cc', '.h'))
  for f in input_api.AffectedFiles(file_filter=file_filter):
    for line_num, line in f.ChangedContents():
      if 'FRIEND_TEST(' in line:
        problems.append('    %s:%d' % (f.LocalPath(), line_num))

  if not problems:
    return []
  return [output_api.PresubmitPromptWarning('Chromium code should not use '
      'gtest\'s FRIEND_TEST() macro. Include base/gtest_prod_util.h and use '
      'FRIEND_TEST_ALL_PREFIXES() instead.\n' + '\n'.join(problems))]


def _CheckNoNewOldCallback(input_api, output_api):
  """Checks to make sure we don't introduce new uses of old callbacks."""

  def HasOldCallbackKeywords(line):
    """Returns True if a line of text contains keywords that indicate the use
    of the old callback system.
    """
    return ('NewRunnableMethod' in line or
            'NewCallback' in line or
            input_api.re.search(r'\bCallback\d<', line) or
            input_api.re.search(r'\bpublic Task\b', line) or
            'public CancelableTask' in line)

  problems = []
  file_filter = lambda f: f.LocalPath().endswith(('.cc', '.h'))
  for f in input_api.AffectedFiles(file_filter=file_filter):
    if not any(HasOldCallbackKeywords(line) for line in f.NewContents()):
      continue
    for line_num, line in f.ChangedContents():
      if HasOldCallbackKeywords(line):
        problems.append('    %s:%d' % (f.LocalPath(), line_num))

  if not problems:
    return []
  return [output_api.PresubmitPromptWarning('The old callback system is '
      'deprecated. If possible, use base::Bind and base::Callback instead.\n' +
      '\n'.join(problems))]


def _CommonChecks(input_api, output_api):
  """Checks common to both upload and commit."""
  results = []
  results.extend(input_api.canned_checks.PanProjectChecks(
      input_api, output_api, excluded_paths=_EXCLUDED_PATHS))
  results.extend(_CheckNoInterfacesInBase(input_api, output_api))
  results.extend(_CheckAuthorizedAuthor(input_api, output_api))
  results.extend(
    _CheckNoProductionCodeUsingTestOnlyFunctions(input_api, output_api))
  results.extend(_CheckNoIOStreamInHeaders(input_api, output_api))
  results.extend(_CheckNoNewWStrings(input_api, output_api))
  results.extend(_CheckNoDEPSGIT(input_api, output_api))
  results.extend(_CheckNoFRIEND_TEST(input_api, output_api))
  results.extend(_CheckNoNewOldCallback(input_api, output_api))
  return results


def _CheckSubversionConfig(input_api, output_api):
  """Verifies the subversion config file is correctly setup.

  Checks that autoprops are enabled, returns an error otherwise.
  """
  join = input_api.os_path.join
  if input_api.platform == 'win32':
    appdata = input_api.environ.get('APPDATA', '')
    if not appdata:
      return [output_api.PresubmitError('%APPDATA% is not configured.')]
    path = join(appdata, 'Subversion', 'config')
  else:
    home = input_api.environ.get('HOME', '')
    if not home:
      return [output_api.PresubmitError('$HOME is not configured.')]
    path = join(home, '.subversion', 'config')

  error_msg = (
      'Please look at http://dev.chromium.org/developers/coding-style to\n'
      'configure your subversion configuration file. This enables automatic\n'
      'properties to simplify the project maintenance.\n'
      'Pro-tip: just download and install\n'
      'http://src.chromium.org/viewvc/chrome/trunk/tools/build/slave/config\n')

  try:
    lines = open(path, 'r').read().splitlines()
    # Make sure auto-props is enabled and check for 2 Chromium standard
    # auto-prop.
    if (not '*.cc = svn:eol-style=LF' in lines or
        not '*.pdf = svn:mime-type=application/pdf' in lines or
        not 'enable-auto-props = yes' in lines):
      return [
          output_api.PresubmitNotifyResult(
              'It looks like you have not configured your subversion config '
              'file or it is not up-to-date.\n' + error_msg)
      ]
  except (OSError, IOError):
    return [
        output_api.PresubmitNotifyResult(
            'Can\'t find your subversion config file.\n' + error_msg)
    ]
  return []


def _CheckAuthorizedAuthor(input_api, output_api):
  """For non-googler/chromites committers, verify the author's email address is
  in AUTHORS.
  """
  # TODO(maruel): Add it to input_api?
  import fnmatch

  author = input_api.change.author_email
  if not author:
    input_api.logging.info('No author, skipping AUTHOR check')
    return []
  authors_path = input_api.os_path.join(
      input_api.PresubmitLocalPath(), 'AUTHORS')
  valid_authors = (
      input_api.re.match(r'[^#]+\s+\<(.+?)\>\s*$', line)
      for line in open(authors_path))
  valid_authors = [item.group(1).lower() for item in valid_authors if item]
  if input_api.verbose:
    print 'Valid authors are %s' % ', '.join(valid_authors)
  if not any(fnmatch.fnmatch(author.lower(), valid) for valid in valid_authors):
    return [output_api.PresubmitPromptWarning(
        ('%s is not in AUTHORS file. If you are a new contributor, please visit'
        '\n'
        'http://www.chromium.org/developers/contributing-code and read the '
        '"Legal" section\n'
        'If you are a chromite, verify the contributor signed the CLA.') %
        author)]
  return []


def CheckChangeOnUpload(input_api, output_api):
  results = []
  results.extend(_CommonChecks(input_api, output_api))
  return results


def CheckChangeOnCommit(input_api, output_api):
  results = []
  results.extend(_CommonChecks(input_api, output_api))
  # TODO(thestig) temporarily disabled, doesn't work in third_party/
  #results.extend(input_api.canned_checks.CheckSvnModifiedDirectories(
  #    input_api, output_api, sources))
  # Make sure the tree is 'open'.
  results.extend(input_api.canned_checks.CheckTreeIsOpen(
      input_api,
      output_api,
      json_url='http://chromium-status.appspot.com/current?format=json'))
  results.extend(input_api.canned_checks.CheckRietveldTryJobExecution(input_api,
      output_api, 'http://codereview.chromium.org',
      ('win_rel', 'linux_rel', 'mac_rel'), 'tryserver@chromium.org'))

  results.extend(input_api.canned_checks.CheckChangeHasBugField(
      input_api, output_api))
  results.extend(input_api.canned_checks.CheckChangeHasTestField(
      input_api, output_api))
  results.extend(input_api.canned_checks.CheckChangeHasDescription(
      input_api, output_api))
  results.extend(_CheckSubversionConfig(input_api, output_api))
  return results


def GetPreferredTrySlaves(project, change):
  only_objc_files = all(
      f.LocalPath().endswith(('.mm', '.m')) for f in change.AffectedFiles())
  if only_objc_files:
    return ['mac_rel']
  preferred = ['win_rel', 'linux_rel', 'mac_rel']
  aura_re = '_aura[^/]*[.][^/]*'
  if any(re.search(aura_re, f.LocalPath()) for f in change.AffectedFiles()):
    preferred.append('linux_chromeos_aura:compile')
  return preferred