#!/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 subprocess
import svn
import sys


GLOBAL_VARIABLES = json.loads(svn.Svn.Cat('http://skia.googlecode.com/svn/'
                                          'buildbot/site_config/'
                                          'global_variables.json'))


def GetGlobalVariable(var_name):
  return GLOBAL_VARIABLES[var_name]['value']


# Alias which can be used to run a try on every builder.
ALL_BUILDERS = 'all'

# Contact information for the build master.
SKIA_BUILD_MASTER_HOST = str(GetGlobalVariable('master_host'))
SKIA_BUILD_MASTER_PORT = str(GetGlobalVariable('external_port'))

# All try builders have this suffix.
TRYBOT_SUFFIX = '_Trybot'

# Location of the codereview.settings file in the Skia repo.
SKIA_URL = 'skia.googlecode.com'
CODEREVIEW_SETTINGS = '/svn/codereview.settings'

# 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(is_svn=True):
  """ Determine where the local checkout is rooted.

  is_svn: boolean; whether we're in an SVN checkout. If False, assume we're in
      a git checkout.
  """
  if is_svn:
    repo = svn.Svn(os.curdir)
    svn_info = repo.GetInfo()
    url = svn_info.get(URL_STR, None)
    repo_root = svn_info.get(REPO_ROOT_STR, None)
    if not url or not repo_root:
      raise Exception('Couldn\'t find checkout root!')
    if url == repo_root:
      return 'svn'
    return url[len(repo_root)+1:]
  else:
    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 in the
  Skia repo. """
  connection = httplib.HTTPConnection(SKIA_URL)
  connection.request('GET', CODEREVIEW_SETTINGS)
  content = connection.getresponse().read()
  for line in content.split('\n'):
    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)


def RetrieveTrybotList():
  """ Retrieve the list of known trybots from the build master, stripping
  TRYBOT_SUFFIX from the name. """
  trybots = []
  connection = httplib.HTTPConnection(SKIA_BUILD_MASTER_HOST,  
                                      SKIA_BUILD_MASTER_PORT)  
  connection.request('GET', '/json/builders')  
  response = connection.getresponse()  
  builders = json.load(response)

  for builder in builders:
    if builder.endswith(TRYBOT_SUFFIX):
      trybots.append(builder[:-len(TRYBOT_SUFFIX)])
  return trybots


def ValidateArgs(argv, 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: A list of the known try builders.
  """

  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> ...]

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

  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':
      print 'submit_try: Available builders:\n  %s' % '\n  '.join(trybots)
      sys.exit(0)
    elif 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('-'):
        bot = argv.pop(0)
        if bot == ALL_BUILDERS:
          if using_bots:
            Error('Cannot specify "all" with additional builder names.')
          using_bots = trybots
          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.')
  return CollectedArgs(bots=using_bots, changelist=changelist,
                       revision=revision)


def SubmitTryRequest(args, is_svn=True):
  """ Submits a try request for the given changelist on the given list of
  trybots.

  args: Object whose properties are derived from command-line arguments. If
      is_svn is True, it should contain:
      - changelist: string; the name of the changelist to try.
      - bot: list of strings; the names of the try builders to run.
      - revision: optional, int; the revision number from which to run the try.
      If is_svn is False, it should contain:
      - bot: list of strings; the names of the try builders to run.
      - revision: optional, int; the revision number from which to run the try. 
  is_svn: boolean; are we in an SVN repo?
  """
  botlist = ','.join(['%s%s' % (bot, TRYBOT_SUFFIX) for bot in args.bots])
  if is_svn:
    gcl_cmd = 'gcl.bat' if os.name == 'nt' else 'gcl'
    try_args = [gcl_cmd, 'try', args.changelist,
                '--root', GetCheckoutRoot(is_svn),
                '--bot', botlist]
    if args.revision:
      try_args.extend(['-r', args.revision])
    print ' '.join(try_args)
    proc = subprocess.Popen(try_args, stdout=subprocess.PIPE,
                            stderr=subprocess.STDOUT)
    if proc.wait() != 0:
      raise Exception('Failed to submit try request: %s' % (
          proc.communicate()[0]))
    print proc.communicate()[0]
  else:
    # First, find depot_tools. This is needed to import trychange.
    sys.path.append(FindDepotTools())
    import trychange
    try_args = ['--use_svn',
                '--svn_repo', GetTryRepo(),
                '--root', GetCheckoutRoot(is_svn),
                '--bot', botlist]
    if args.revision:
      try_args.extend(['-r', args.revision])
    trychange.TryChange(try_args, None, False)


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

  # Submit the try request.
  SubmitTryRequest(args, is_svn=is_svn)


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