#!/usr/bin/python

# Copyright (c) 2013 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.


"""
submit_try: Submit a try request.

This is a thin wrapper around the try request utilities in depot_tools which
adds some validation and supports both git and svn.
"""


import httplib
import json
import os
import re
import shutil
import subprocess
import sys
import tempfile

import retrieve_from_googlesource


# Alias which can be used to run a try on every builder.
ALL_BUILDERS = 'all'
# Alias which can be used to run a try on all compile builders.
COMPILE_BUILDERS = 'compile'
# Alias which can be used to run a try on all builders that are run in the CQ.
CQ_BUILDERS = 'cq'
# Alias which can be used to specify a regex to choose builders.
REGEX = 'regex'

ALL_ALIASES = [ALL_BUILDERS, COMPILE_BUILDERS, REGEX, CQ_BUILDERS]

LARGE_NUMBER_OF_BOTS = 5

GIT = 'git.bat' if os.name == 'nt' else 'git'

# URL of the slaves.cfg file in the Skia buildbot sources.
SKIA_REPO = 'https://skia.googlesource.com/buildbot'
SLAVES_CFG_PATH = 'master/slaves.cfg'

# All try builders have this suffix.
TRYBOT_SUFFIX = '-Trybot'

# String for matching the svn url of the try server inside codereview.settings.
TRYSERVER_SVN_URL = 'TRYSERVER_SVN_URL: '

# Strings used for matching svn config properties.
URL_STR = 'URL'
REPO_ROOT_STR = 'Repository Root'


def FindDepotTools():
  """ Find depot_tools on the local machine and return its location. """
  which_cmd = 'where' if os.name == 'nt' else 'which'
  cmd = [which_cmd, 'gcl']
  proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
  if proc.wait() != 0:
    raise Exception('Couldn\'t find depot_tools in PATH!')
  gcl = proc.communicate()[0].split('\n')[0].rstrip()
  depot_tools_dir = os.path.dirname(gcl)
  return depot_tools_dir


def GetCheckoutRoot():
  """ Determine where the local checkout is rooted."""
  cmd = ['git', 'rev-parse', '--show-toplevel']
  proc = subprocess.Popen(cmd, stdout=subprocess.PIPE,
                          stderr=subprocess.STDOUT)
  if proc.wait() != 0:
    raise Exception('Couldn\'t find checkout root!')
  return os.path.basename(proc.communicate()[0])


def GetTryRepo():
  """Determine the TRYSERVER_SVN_URL from the codereview.settings file."""
  codereview_settings_file = os.path.join(os.path.dirname(__file__), os.pardir,
                                          'codereview.settings')
  with open(codereview_settings_file) as f:
    for line in f:
      if line.startswith(TRYSERVER_SVN_URL):
        return line[len(TRYSERVER_SVN_URL):].rstrip()
  raise Exception('Couldn\'t determine the TRYSERVER_SVN_URL. Make sure it is '
                  'defined in the %s file.' % codereview_settings_file)


def RetrieveTrybotList():
  """Retrieve the list of known trybots from the checked-in buildbot
  configuration."""
  # Retrieve the slaves.cfg file from the repository.
  slaves_cfg_text = retrieve_from_googlesource.get(SKIA_REPO, SLAVES_CFG_PATH)

  # Execute the slaves.cfg file to obtain the list of slaves.
  vars = {}
  exec(slaves_cfg_text, vars)
  slaves_cfg = vars['slaves']

  # Pull the list of known builders from the slaves list.
  trybots = set()
  for slave in slaves_cfg:
    for builder in slave['builder']:
      if not builder.endswith(TRYBOT_SUFFIX):
        trybots.add(builder)

  return list(trybots), vars['cq_trybots']


def ValidateArgs(argv, trybots, cq_trybots, is_svn=True):
  """ Parse and validate command-line arguments. If the arguments are valid,
  returns a tuple of (<changelist name>, <list of trybots>).

  trybots: list of strings; A list of the known try builders.
  cq_trybots: list of strings; Trybots who get run by the commit queue.
  is_svn: bool; whether or not we're in an svn checkout.
  """

  class CollectedArgs(object):
    def __init__(self, bots, changelist, revision):
      self._bots = bots
      self._changelist = changelist
      self._revision = revision

    @property
    def bots(self):
      for bot in self._bots:
        yield bot

    @property
    def changelist(self):
      return self._changelist

    @property
    def revision(self):
      return self._revision

  usage = (
"""submit_try: Submit a try request.
submit_try %s--bot <buildername> [<buildername> ...]

-b, --bot           Builder(s) or Alias on which to run the try. Required.
                    Allowed aliases: %s
-h, --help          Show this message.
-r <revision#>      Revision from which to run the try.
-l, --list_bots     List the available try builders and aliases and exit.
""" % ('<changelist> ' if is_svn else '', ALL_ALIASES))

  def Error(msg=None):
    if msg:
      print msg
    print usage
    sys.exit(1)

  using_bots = None
  changelist = None
  revision = None

  while argv:
    arg = argv.pop(0)
    if arg == '-h' or arg == '--help':
      Error()
    elif arg == '-l' or arg == '--list_bots':
      format_args = ['\n  '.join(sorted(trybots))] + \
                    ALL_ALIASES + \
                    ['\n    '.join(sorted(cq_trybots))]
      print (
"""
submit_try: Available builders:\n  %s

Can also use the following aliases to run on groups of builders-
  %s: Will run against all trybots.
  %s: Will run against all compile trybots.
  %s: You will be prompted to enter a regex to select builders with.
  %s: Will run against the same trybots as the commit queue:\n    %s

""" % tuple(format_args))
      sys.exit(0)
    elif arg == '-b' or arg == '--bot':
      if using_bots:
        Error('--bot specified multiple times.')
      if len(argv) < 1:
        Error('You must specify a builder with "--bot".')
      using_bots = []
      while argv and not argv[0].startswith('-'):
        for bot in argv.pop(0).split(','):
          if bot in ALL_ALIASES:
            if using_bots:
              Error('Cannot specify "%s" with additional builder names or '
                    'aliases.' % bot)
            elif bot == COMPILE_BUILDERS:
              using_bots = [t for t in trybots if t.startswith('Build')]
            elif bot == CQ_BUILDERS:
              using_bots = cq_trybots
            elif bot == REGEX:
              while True:
                regex = raw_input("Enter your trybot regex: ")
                p = re.compile(regex)
                using_bots = [t for t in trybots if p.match(t)]
                print '\n\nTrybots that match your regex:\n%s\n\n' % '\n'.join(
                    using_bots)
                if raw_input('Re-enter regex? [y,n]: ') == 'n':
                  break
            break
          else:
            if not bot in trybots:
              Error('Unrecognized builder: %s' % bot)
            using_bots.append(bot)
    elif arg == '-r':
      if len(argv) < 1:
        Error('You must specify a revision with "-r".')
      revision = argv.pop(0)
    else:
      if changelist or not is_svn:
        Error('Unknown argument: %s' % arg)
      changelist = arg
  if is_svn and not changelist:
    Error('You must specify a changelist name.')
  if not using_bots:
    Error('You must specify one or more builders using --bot.')
  if len(using_bots) > LARGE_NUMBER_OF_BOTS:
    are_you_sure = raw_input('Running a try on a large number of bots is very '
                             'expensive. You may be able to get enough '
                             'information by running on a smaller set of bots. '
                             'Are you sure you want to do this? [y,n]: ')
    if are_you_sure != 'y':
      Error()
  return CollectedArgs(bots=using_bots, changelist=changelist,
                       revision=revision)


def SubmitTryRequest(trybots, revision=None):
  """ Submits a try request on the given list of trybots.

  Args:
      trybots: list of strings; the names of the try builders to run.
      revision: optional string; the revision from which to run the try.
  """
  botlist = ','.join(['%s%s' % (bot, TRYBOT_SUFFIX) for bot in trybots])
  # Find depot_tools. This is needed to import git_cl and trychange.
  sys.path.append(FindDepotTools())
  import git_cl
  import trychange

  cmd = [GIT, 'diff', git_cl.Changelist().GetUpstreamBranch(),
         '--no-ext-diff']
  proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
  git_data = proc.communicate()
  if git_data[0] is None:
    raise Exception('Failed to capture git diff!')

  temp_dir = tempfile.mkdtemp()
  try:
    diff_file = os.path.join(temp_dir, 'patch.diff')
    with open(diff_file, 'wb') as f:
      f.write(git_data[0])
      f.close()

    try_args = ['--use_svn',
                '--svn_repo', GetTryRepo(),
                '--root', GetCheckoutRoot(),
                '--bot', botlist,
                '--diff', diff_file,
                ]
    if revision:
      try_args.extend(['-r', revision])

    # Submit the try request.
    trychange.TryChange(try_args, None, False)
  finally:
    shutil.rmtree(temp_dir)


def main():
  # Retrieve the list of active try builders from the build master.
  trybots, cq_trybots = RetrieveTrybotList()

  # Determine if we're in an SVN checkout.
  is_svn = os.path.isdir('.svn')

  # Parse and validate the command-line arguments.
  args = ValidateArgs(sys.argv[1:], trybots=trybots, cq_trybots=cq_trybots,
                      is_svn=is_svn)

  # Submit the try request.
  SubmitTryRequest(args.bots, args.revision)


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