#!/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 svn
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())