#!/usr/bin/python
"""Run tests in parallel."""

import argparse
import glob
import itertools
import multiprocessing
import os
import sys
import time

import jobset
import simplejson
import watch_dirs


# SimpleConfig: just compile with CONFIG=config, and run the binary to test
class SimpleConfig(object):

  def __init__(self, config):
    self.build_config = config
    self.maxjobs = 32 * multiprocessing.cpu_count()

  def run_command(self, binary):
    return [binary]


# ValgrindConfig: compile with some CONFIG=config, but use valgrind to run
class ValgrindConfig(object):

  def __init__(self, config, tool):
    self.build_config = config
    self.tool = tool
    self.maxjobs = 4 * multiprocessing.cpu_count()

  def run_command(self, binary):
    return ['valgrind', binary, '--tool=%s' % self.tool]


# different configurations we can run under
_CONFIGS = {
    'dbg': SimpleConfig('dbg'),
    'opt': SimpleConfig('opt'),
    'tsan': SimpleConfig('tsan'),
    'msan': SimpleConfig('msan'),
    'asan': SimpleConfig('asan'),
    'gcov': SimpleConfig('gcov'),
    'memcheck': ValgrindConfig('valgrind', 'memcheck'),
    'helgrind': ValgrindConfig('dbg', 'helgrind')
    }


_DEFAULT = ['dbg', 'opt']
_LANGUAGE_TEST_TARGETS = {
    'c++': 'buildtests_cxx',
    'c': 'buildtests_c',
}

# parse command line
argp = argparse.ArgumentParser(description='Run grpc tests.')
argp.add_argument('-c', '--config',
                  choices=['all'] + sorted(_CONFIGS.keys()),
                  nargs='+',
                  default=_DEFAULT)
argp.add_argument('-t', '--test-filter', nargs='*', default=['*'])
argp.add_argument('-n', '--runs_per_test', default=1, type=int)
argp.add_argument('-f', '--forever',
                  default=False,
                  action='store_const',
                  const=True)
argp.add_argument('--newline_on_success',
                  default=False,
                  action='store_const',
                  const=True)
argp.add_argument('-l', '--language',
                  choices=sorted(_LANGUAGE_TEST_TARGETS.keys()),
                  nargs='+',
                  default=sorted(_LANGUAGE_TEST_TARGETS.keys()))
args = argp.parse_args()

# grab config
run_configs = set(_CONFIGS[cfg]
                  for cfg in itertools.chain.from_iterable(
                      _CONFIGS.iterkeys() if x == 'all' else [x]
                      for x in args.config))
build_configs = set(cfg.build_config for cfg in run_configs)
make_targets = set(_LANGUAGE_TEST_TARGETS[x] for x in args.language)
filters = args.test_filter
runs_per_test = args.runs_per_test
forever = args.forever


class TestCache(object):
  """Cache for running tests."""

  def __init__(self):
    self._last_successful_run = {}

  def should_run(self, cmdline, bin_hash):
    cmdline = ' '.join(cmdline)
    if cmdline not in self._last_successful_run:
      return True
    if self._last_successful_run[cmdline] != bin_hash:
      return True
    return False

  def finished(self, cmdline, bin_hash):
    self._last_successful_run[' '.join(cmdline)] = bin_hash

  def dump(self):
    return [{'cmdline': k, 'hash': v}
            for k, v in self._last_successful_run.iteritems()]

  def parse(self, exdump):
    self._last_successful_run = dict((o['cmdline'], o['hash']) for o in exdump)

  def save(self):
    with open('.run_tests_cache', 'w') as f:
      f.write(simplejson.dumps(self.dump()))

  def maybe_load(self):
    if os.path.exists('.run_tests_cache'):
      with open('.run_tests_cache') as f:
        self.parse(simplejson.loads(f.read()))


def _build_and_run(check_cancelled, newline_on_success, cache):
  """Do one pass of building & running tests."""
  # build latest, sharing cpu between the various makes
  if not jobset.run(
      (['make',
        '-j', '%d' % (multiprocessing.cpu_count() + 1),
        'CONFIG=%s' % cfg] + list(make_targets)
       for cfg in build_configs),
      check_cancelled, maxjobs=1):
    return 1

  # run all the tests
  if not jobset.run(
      itertools.ifilter(
          lambda x: x is not None, (
              config.run_command(x)
              for config in run_configs
              for filt in filters
              for x in itertools.chain.from_iterable(itertools.repeat(
                  glob.glob('bins/%s/%s_test' % (
                      config.build_config, filt)),
                  runs_per_test)))),
      check_cancelled,
      newline_on_success=newline_on_success,
      maxjobs=min(c.maxjobs for c in run_configs),
      cache=cache):
    return 2

  return 0


test_cache = (None if runs_per_test != 1
              or 'gcov' in build_configs
              or 'valgrind' in build_configs
              else TestCache())
if test_cache:
  test_cache.maybe_load()

if forever:
  success = True
  while True:
    dw = watch_dirs.DirWatcher(['src', 'include', 'test'])
    initial_time = dw.most_recent_change()
    have_files_changed = lambda: dw.most_recent_change() != initial_time
    previous_success = success
    success = _build_and_run(check_cancelled=have_files_changed,
                             newline_on_success=False,
                             cache=test_cache) == 0
    if not previous_success and success:
      jobset.message('SUCCESS',
                     'All tests are now passing properly',
                     do_newline=True)
    jobset.message('IDLE', 'No change detected')
    while not have_files_changed():
      time.sleep(1)
else:
  result = _build_and_run(check_cancelled=lambda: False,
                          newline_on_success=args.newline_on_success,
                          cache=test_cache)
  if result == 0:
    jobset.message('SUCCESS', 'All tests passed', do_newline=True)
  else:
    jobset.message('FAILED', 'Some tests failed', do_newline=True)
  test_cache.save()
  sys.exit(result)