#!/usr/bin/env python
# Copyright (c) 2016 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.

"""This script takes a Clang git revision as an argument, it then
creates a feature branch, puts this revision into update.py, uploads
a CL, triggers Clang Upload try bots, and tells what to do next"""

import argparse
import fnmatch
import itertools
import os
import re
import shutil
import subprocess
import sys

from build import GetSvnRevision

# Path constants.
THIS_DIR = os.path.dirname(__file__)
UPDATE_PY_PATH = os.path.join(THIS_DIR, "update.py")
CHROMIUM_DIR = os.path.abspath(os.path.join(THIS_DIR, '..', '..', '..'))

is_win = sys.platform.startswith('win32')

def PatchRevision(clang_git_revision, clang_svn_revision, clang_sub_revision):
  with open(UPDATE_PY_PATH, 'rb') as f:
    content = f.read()
  m = re.search("CLANG_SVN_REVISION = '([0-9]+)'", content)
  clang_old_revision = m.group(1)

  content = re.sub("CLANG_REVISION = '[0-9a-f]+'",
                   "CLANG_REVISION = '{}'".format(clang_git_revision),
                   content, count=1)
  content = re.sub("CLANG_SVN_REVISION = '[0-9]+'",
                   "CLANG_SVN_REVISION = '{}'".format(clang_svn_revision),
                   content, count=1)
  content = re.sub("CLANG_SUB_REVISION = [0-9]+",
                   "CLANG_SUB_REVISION = {}".format(clang_sub_revision),
                   content, count=1)
  with open(UPDATE_PY_PATH, 'wb') as f:
    f.write(content)
  return clang_old_revision


def Git(args):
  # Needs shell=True on Windows due to git.bat in depot_tools.
  subprocess.check_call(["git"] + args, shell=is_win)

def main():
  parser = argparse.ArgumentParser(description='upload new clang revision')
  parser.add_argument('clang_git_revision', nargs=1,
                      help='Clang git revision to build the toolchain for.')
  parser.add_argument('clang_sub_revision',
                      type=int, nargs='?', default=1,
                      help='Clang sub-revision to build the toolchain for.')

  args = parser.parse_args()

  clang_git_revision = args.clang_git_revision[0]
  clang_svn_revision = GetSvnRevision(clang_git_revision)
  clang_sub_revision = args.clang_sub_revision

  # Needs shell=True on Windows due to git.bat in depot_tools.
  git_revision = subprocess.check_output(
      ["git", "rev-parse", "origin/master"], shell=is_win).strip()

  print "Making a patch for Clang {}-{}-{}".format(clang_svn_revision,
                                                   clang_git_revision[:8],
                                                   clang_sub_revision)
  print "Chrome revision: {}".format(git_revision)

  clang_old_revision = PatchRevision(clang_git_revision, clang_svn_revision,
                                     clang_sub_revision)

  Git(["checkout", "-b", "clang-{}-{}-{}".format(clang_svn_revision,
                                                 clang_git_revision[:8],
                                                 clang_sub_revision)])
  Git(["add", UPDATE_PY_PATH])

  commit_message = 'Ran `{}`.'.format(' '.join(sys.argv))
  Git(["commit", "-m", "Roll clang {}:{}.\n\n{}".format(
      clang_old_revision, clang_svn_revision, commit_message)])

  Git(["cl", "upload", "-f", "--bypass-hooks"])
  Git(["cl", "try", "-B", "luci.chromium.try",
       "-b", "linux_upload_clang",
       "-b", "mac_upload_clang",
       "-b", "win_upload_clang",
       "-r", git_revision])

  print ("Please, wait until the try bots succeeded "
         "and then push the binaries to goma.")

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