#!/usr/bin/env python
#
# Copyright 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.

"""Runs all types of tests from one unified interface."""

import collections
import logging
import optparse
import os
import shutil
import signal
import sys
import threading

from pylib import android_commands
from pylib import constants
from pylib import forwarder
from pylib import ports
from pylib.base import base_test_result
from pylib.base import test_dispatcher
from pylib.gtest import gtest_config
from pylib.gtest import setup as gtest_setup
from pylib.gtest import test_options as gtest_test_options
from pylib.linker import setup as linker_setup
from pylib.host_driven import setup as host_driven_setup
from pylib.instrumentation import setup as instrumentation_setup
from pylib.instrumentation import test_options as instrumentation_test_options
from pylib.junit import setup as junit_setup
from pylib.junit import test_dispatcher as junit_dispatcher
from pylib.monkey import setup as monkey_setup
from pylib.monkey import test_options as monkey_test_options
from pylib.perf import setup as perf_setup
from pylib.perf import test_options as perf_test_options
from pylib.perf import test_runner as perf_test_runner
from pylib.uiautomator import setup as uiautomator_setup
from pylib.uiautomator import test_options as uiautomator_test_options
from pylib.utils import apk_helper
from pylib.utils import command_option_parser
from pylib.utils import report_results
from pylib.utils import reraiser_thread
from pylib.utils import run_tests_helper


def AddCommonOptions(option_parser):
  """Adds all common options to |option_parser|."""

  group = optparse.OptionGroup(option_parser, 'Common Options')
  default_build_type = os.environ.get('BUILDTYPE', 'Debug')
  group.add_option('--debug', action='store_const', const='Debug',
                   dest='build_type', default=default_build_type,
                   help=('If set, run test suites under out/Debug. '
                         'Default is env var BUILDTYPE or Debug.'))
  group.add_option('--release', action='store_const',
                   const='Release', dest='build_type',
                   help=('If set, run test suites under out/Release.'
                         ' Default is env var BUILDTYPE or Debug.'))
  group.add_option('--build-directory', dest='build_directory',
                   help=('Path to the directory in which build files are'
                         ' located (should not include build type)'))
  group.add_option('-c', dest='cleanup_test_files',
                   help='Cleanup test files on the device after run',
                   action='store_true')
  group.add_option('--num_retries', dest='num_retries', type='int',
                   default=2,
                   help=('Number of retries for a test before '
                         'giving up.'))
  group.add_option('-v',
                   '--verbose',
                   dest='verbose_count',
                   default=0,
                   action='count',
                   help='Verbose level (multiple times for more)')
  group.add_option('--tool',
                   dest='tool',
                   help=('Run the test under a tool '
                         '(use --tool help to list them)'))
  group.add_option('--flakiness-dashboard-server',
                   dest='flakiness_dashboard_server',
                   help=('Address of the server that is hosting the '
                         'Chrome for Android flakiness dashboard.'))
  group.add_option('--skip-deps-push', dest='push_deps',
                   action='store_false', default=True,
                   help=('Do not push dependencies to the device. '
                         'Use this at own risk for speeding up test '
                         'execution on local machine.'))
  group.add_option('-d', '--device', dest='test_device',
                   help=('Target device for the test suite '
                         'to run on.'))
  option_parser.add_option_group(group)


def ProcessCommonOptions(options):
  """Processes and handles all common options."""
  run_tests_helper.SetLogLevel(options.verbose_count)
  constants.SetBuildType(options.build_type)
  if options.build_directory:
    constants.SetBuildDirectory(options.build_directory)


def AddGTestOptions(option_parser):
  """Adds gtest options to |option_parser|."""

  option_parser.usage = '%prog gtest [options]'
  option_parser.commands_dict = {}
  option_parser.example = '%prog gtest -s base_unittests'

  # TODO(gkanwar): Make this option required
  option_parser.add_option('-s', '--suite', dest='suite_name',
                           help=('Executable name of the test suite to run '
                                 '(use -s help to list them).'))
  option_parser.add_option('-f', '--gtest_filter', '--gtest-filter',
                           dest='test_filter',
                           help='googletest-style filter string.')
  option_parser.add_option('--gtest_also_run_disabled_tests',
                           '--gtest-also-run-disabled-tests',
                           dest='run_disabled', action='store_true',
                           help='Also run disabled tests if applicable.')
  option_parser.add_option('-a', '--test-arguments', dest='test_arguments',
                           default='',
                           help='Additional arguments to pass to the test.')
  option_parser.add_option('-t', dest='timeout',
                           help='Timeout to wait for each test',
                           type='int',
                           default=60)
  option_parser.add_option('--isolate_file_path',
                           '--isolate-file-path',
                           dest='isolate_file_path',
                           help='.isolate file path to override the default '
                                'path')
  # TODO(gkanwar): Move these to Common Options once we have the plumbing
  # in our other test types to handle these commands
  AddCommonOptions(option_parser)


def AddLinkerTestOptions(option_parser):
  option_parser.usage = '%prog linker'
  option_parser.commands_dict = {}
  option_parser.example = '%prog linker'

  option_parser.add_option('-f', '--gtest-filter', dest='test_filter',
                           help='googletest-style filter string.')
  AddCommonOptions(option_parser)


def ProcessGTestOptions(options):
  """Intercept test suite help to list test suites.

  Args:
    options: Command line options.
  """
  if options.suite_name == 'help':
    print 'Available test suites are:'
    for test_suite in (gtest_config.STABLE_TEST_SUITES +
                       gtest_config.EXPERIMENTAL_TEST_SUITES):
      print test_suite
    sys.exit(0)

  # Convert to a list, assuming all test suites if nothing was specified.
  # TODO(gkanwar): Require having a test suite
  if options.suite_name:
    options.suite_name = [options.suite_name]
  else:
    options.suite_name = [s for s in gtest_config.STABLE_TEST_SUITES]


def AddJavaTestOptions(option_parser):
  """Adds the Java test options to |option_parser|."""

  option_parser.add_option('-f', '--test-filter', dest='test_filter',
                           help=('Test filter (if not fully qualified, '
                                 'will run all matches).'))
  option_parser.add_option(
      '-A', '--annotation', dest='annotation_str',
      help=('Comma-separated list of annotations. Run only tests with any of '
            'the given annotations. An annotation can be either a key or a '
            'key-values pair. A test that has no annotation is considered '
            '"SmallTest".'))
  option_parser.add_option(
      '-E', '--exclude-annotation', dest='exclude_annotation_str',
      help=('Comma-separated list of annotations. Exclude tests with these '
            'annotations.'))
  option_parser.add_option(
      '--screenshot', dest='screenshot_failures', action='store_true',
      help='Capture screenshots of test failures')
  option_parser.add_option(
      '--save-perf-json', action='store_true',
      help='Saves the JSON file for each UI Perf test.')
  option_parser.add_option(
      '--official-build', action='store_true', help='Run official build tests.')
  option_parser.add_option(
      '--test_data', '--test-data', action='append', default=[],
      help=('Each instance defines a directory of test data that should be '
            'copied to the target(s) before running the tests. The argument '
            'should be of the form <target>:<source>, <target> is relative to '
            'the device data directory, and <source> is relative to the '
            'chromium build directory.'))


def ProcessJavaTestOptions(options):
  """Processes options/arguments and populates |options| with defaults."""

  if options.annotation_str:
    options.annotations = options.annotation_str.split(',')
  elif options.test_filter:
    options.annotations = []
  else:
    options.annotations = ['Smoke', 'SmallTest', 'MediumTest', 'LargeTest',
                           'EnormousTest', 'IntegrationTest']

  if options.exclude_annotation_str:
    options.exclude_annotations = options.exclude_annotation_str.split(',')
  else:
    options.exclude_annotations = []


def AddInstrumentationTestOptions(option_parser):
  """Adds Instrumentation test options to |option_parser|."""

  option_parser.usage = '%prog instrumentation [options]'
  option_parser.commands_dict = {}
  option_parser.example = ('%prog instrumentation '
                           '--test-apk=ChromeShellTest')

  AddJavaTestOptions(option_parser)
  AddCommonOptions(option_parser)

  option_parser.add_option('-j', '--java-only', action='store_true',
                           default=False, help='Run only the Java tests.')
  option_parser.add_option('-p', '--python-only', action='store_true',
                           default=False,
                           help='Run only the host-driven tests.')
  option_parser.add_option('--host-driven-root',
                           help='Root of the host-driven tests.')
  option_parser.add_option('-w', '--wait_debugger', dest='wait_for_debugger',
                           action='store_true',
                           help='Wait for debugger.')
  option_parser.add_option(
      '--test-apk', dest='test_apk',
      help=('The name of the apk containing the tests '
            '(without the .apk extension; e.g. "ContentShellTest").'))
  option_parser.add_option('--coverage-dir',
                           help=('Directory in which to place all generated '
                                 'EMMA coverage files.'))
  option_parser.add_option('--device-flags', dest='device_flags', default='',
                           help='The relative filepath to a file containing '
                                'command-line flags to set on the device')


def ProcessInstrumentationOptions(options, error_func):
  """Processes options/arguments and populate |options| with defaults.

  Args:
    options: optparse.Options object.
    error_func: Function to call with the error message in case of an error.

  Returns:
    An InstrumentationOptions named tuple which contains all options relevant to
    instrumentation tests.
  """

  ProcessJavaTestOptions(options)

  if options.java_only and options.python_only:
    error_func('Options java_only (-j) and python_only (-p) '
               'are mutually exclusive.')
  options.run_java_tests = True
  options.run_python_tests = True
  if options.java_only:
    options.run_python_tests = False
  elif options.python_only:
    options.run_java_tests = False

  if not options.host_driven_root:
    options.run_python_tests = False

  if not options.test_apk:
    error_func('--test-apk must be specified.')


  options.test_apk_path = os.path.join(
      constants.GetOutDirectory(),
      constants.SDK_BUILD_APKS_DIR,
      '%s.apk' % options.test_apk)
  options.test_apk_jar_path = os.path.join(
      constants.GetOutDirectory(),
      constants.SDK_BUILD_TEST_JAVALIB_DIR,
      '%s.jar' %  options.test_apk)
  options.test_support_apk_path = '%sSupport%s' % (
      os.path.splitext(options.test_apk_path))

  options.test_runner = apk_helper.GetInstrumentationName(options.test_apk_path)

  return instrumentation_test_options.InstrumentationOptions(
      options.tool,
      options.cleanup_test_files,
      options.push_deps,
      options.annotations,
      options.exclude_annotations,
      options.test_filter,
      options.test_data,
      options.save_perf_json,
      options.screenshot_failures,
      options.wait_for_debugger,
      options.coverage_dir,
      options.test_apk,
      options.test_apk_path,
      options.test_apk_jar_path,
      options.test_runner,
      options.test_support_apk_path,
      options.device_flags
      )


def AddUIAutomatorTestOptions(option_parser):
  """Adds UI Automator test options to |option_parser|."""

  option_parser.usage = '%prog uiautomator [options]'
  option_parser.commands_dict = {}
  option_parser.example = (
      '%prog uiautomator --test-jar=chrome_shell_uiautomator_tests'
      ' --package=chrome_shell')
  option_parser.add_option(
      '--package',
      help=('Package under test. Possible values: %s' %
            constants.PACKAGE_INFO.keys()))
  option_parser.add_option(
      '--test-jar', dest='test_jar',
      help=('The name of the dexed jar containing the tests (without the '
            '.dex.jar extension). Alternatively, this can be a full path '
            'to the jar.'))

  AddJavaTestOptions(option_parser)
  AddCommonOptions(option_parser)


def ProcessUIAutomatorOptions(options, error_func):
  """Processes UIAutomator options/arguments.

  Args:
    options: optparse.Options object.
    error_func: Function to call with the error message in case of an error.

  Returns:
    A UIAutomatorOptions named tuple which contains all options relevant to
    uiautomator tests.
  """

  ProcessJavaTestOptions(options)

  if not options.package:
    error_func('--package is required.')

  if options.package not in constants.PACKAGE_INFO:
    error_func('Invalid package.')

  if not options.test_jar:
    error_func('--test-jar must be specified.')

  if os.path.exists(options.test_jar):
    # The dexed JAR is fully qualified, assume the info JAR lives along side.
    options.uiautomator_jar = options.test_jar
  else:
    options.uiautomator_jar = os.path.join(
        constants.GetOutDirectory(),
        constants.SDK_BUILD_JAVALIB_DIR,
        '%s.dex.jar' % options.test_jar)
  options.uiautomator_info_jar = (
      options.uiautomator_jar[:options.uiautomator_jar.find('.dex.jar')] +
      '_java.jar')

  return uiautomator_test_options.UIAutomatorOptions(
      options.tool,
      options.cleanup_test_files,
      options.push_deps,
      options.annotations,
      options.exclude_annotations,
      options.test_filter,
      options.test_data,
      options.save_perf_json,
      options.screenshot_failures,
      options.uiautomator_jar,
      options.uiautomator_info_jar,
      options.package)


def AddJUnitTestOptions(option_parser):
  """Adds junit test options to |option_parser|."""
  option_parser.usage = '%prog junit -s [test suite name]'
  option_parser.commands_dict = {}

  option_parser.add_option(
      '-s', '--test-suite', dest='test_suite',
      help=('JUnit test suite to run.'))
  option_parser.add_option(
      '-f', '--test-filter', dest='test_filter',
      help='Filters tests googletest-style.')
  option_parser.add_option(
      '--package-filter', dest='package_filter',
      help='Filters tests by package.')
  option_parser.add_option(
      '--runner-filter', dest='runner_filter',
      help='Filters tests by runner class. Must be fully qualified.')
  option_parser.add_option(
      '--sdk-version', dest='sdk_version', type="int",
      help='The Android SDK version.')
  AddCommonOptions(option_parser)


def ProcessJUnitTestOptions(options, error_func):
  """Processes all JUnit test options."""
  if not options.test_suite:
    error_func('No test suite specified.')
  return options


def AddMonkeyTestOptions(option_parser):
  """Adds monkey test options to |option_parser|."""

  option_parser.usage = '%prog monkey [options]'
  option_parser.commands_dict = {}
  option_parser.example = (
      '%prog monkey --package=chrome_shell')

  option_parser.add_option(
      '--package',
      help=('Package under test. Possible values: %s' %
            constants.PACKAGE_INFO.keys()))
  option_parser.add_option(
      '--event-count', default=10000, type='int',
      help='Number of events to generate [default: %default].')
  option_parser.add_option(
      '--category', default='',
      help='A list of allowed categories.')
  option_parser.add_option(
      '--throttle', default=100, type='int',
      help='Delay between events (ms) [default: %default]. ')
  option_parser.add_option(
      '--seed', type='int',
      help=('Seed value for pseudo-random generator. Same seed value generates '
            'the same sequence of events. Seed is randomized by default.'))
  option_parser.add_option(
      '--extra-args', default='',
      help=('String of other args to pass to the command verbatim '
            '[default: "%default"].'))

  AddCommonOptions(option_parser)


def ProcessMonkeyTestOptions(options, error_func):
  """Processes all monkey test options.

  Args:
    options: optparse.Options object.
    error_func: Function to call with the error message in case of an error.

  Returns:
    A MonkeyOptions named tuple which contains all options relevant to
    monkey tests.
  """
  if not options.package:
    error_func('--package is required.')

  if options.package not in constants.PACKAGE_INFO:
    error_func('Invalid package.')

  category = options.category
  if category:
    category = options.category.split(',')

  return monkey_test_options.MonkeyOptions(
      options.verbose_count,
      options.package,
      options.event_count,
      category,
      options.throttle,
      options.seed,
      options.extra_args)


def AddPerfTestOptions(option_parser):
  """Adds perf test options to |option_parser|."""

  option_parser.usage = '%prog perf [options]'
  option_parser.commands_dict = {}
  option_parser.example = ('%prog perf '
                           '[--single-step -- command args] or '
                           '[--steps perf_steps.json] or '
                           '[--print-step step]')

  option_parser.add_option(
      '--single-step',
      action='store_true',
      help='Execute the given command with retries, but only print the result '
           'for the "most successful" round.')
  option_parser.add_option(
      '--steps',
      help='JSON file containing the list of commands to run.')
  option_parser.add_option(
      '--flaky-steps',
      help=('A JSON file containing steps that are flaky '
            'and will have its exit code ignored.'))
  option_parser.add_option(
      '--output-json-list',
      help='Write a simple list of names from --steps into the given file.')
  option_parser.add_option(
      '--print-step',
      help='The name of a previously executed perf step to print.')
  option_parser.add_option(
      '--no-timeout', action='store_true',
      help=('Do not impose a timeout. Each perf step is responsible for '
            'implementing the timeout logic.'))
  option_parser.add_option(
      '-f', '--test-filter',
      help=('Test filter (will match against the names listed in --steps).'))
  option_parser.add_option(
      '--dry-run',
      action='store_true',
      help='Just print the steps without executing.')
  AddCommonOptions(option_parser)


def ProcessPerfTestOptions(options, args, error_func):
  """Processes all perf test options.

  Args:
    options: optparse.Options object.
    error_func: Function to call with the error message in case of an error.

  Returns:
    A PerfOptions named tuple which contains all options relevant to
    perf tests.
  """
  # Only one of steps, print_step or single_step must be provided.
  count = len(filter(None,
                     [options.steps, options.print_step, options.single_step]))
  if count != 1:
    error_func('Please specify one of: --steps, --print-step, --single-step.')
  single_step = None
  if options.single_step:
    single_step = ' '.join(args[2:])
  return perf_test_options.PerfOptions(
      options.steps, options.flaky_steps, options.output_json_list,
      options.print_step, options.no_timeout, options.test_filter,
      options.dry_run, single_step)


def _RunGTests(options, devices):
  """Subcommand of RunTestsCommands which runs gtests."""
  ProcessGTestOptions(options)

  exit_code = 0
  for suite_name in options.suite_name:
    # TODO(gkanwar): Move this into ProcessGTestOptions once we require -s for
    # the gtest command.
    gtest_options = gtest_test_options.GTestOptions(
        options.tool,
        options.cleanup_test_files,
        options.push_deps,
        options.test_filter,
        options.run_disabled,
        options.test_arguments,
        options.timeout,
        options.isolate_file_path,
        suite_name)
    runner_factory, tests = gtest_setup.Setup(gtest_options, devices)

    results, test_exit_code = test_dispatcher.RunTests(
        tests, runner_factory, devices, shard=True, test_timeout=None,
        num_retries=options.num_retries)

    if test_exit_code and exit_code != constants.ERROR_EXIT_CODE:
      exit_code = test_exit_code

    report_results.LogFull(
        results=results,
        test_type='Unit test',
        test_package=suite_name,
        flakiness_server=options.flakiness_dashboard_server)

  if os.path.isdir(constants.ISOLATE_DEPS_DIR):
    shutil.rmtree(constants.ISOLATE_DEPS_DIR)

  return exit_code


def _RunLinkerTests(options, devices):
  """Subcommand of RunTestsCommands which runs linker tests."""
  runner_factory, tests = linker_setup.Setup(options, devices)

  results, exit_code = test_dispatcher.RunTests(
      tests, runner_factory, devices, shard=True, test_timeout=60,
      num_retries=options.num_retries)

  report_results.LogFull(
      results=results,
      test_type='Linker test',
      test_package='ChromiumLinkerTest')

  return exit_code


def _RunInstrumentationTests(options, error_func, devices):
  """Subcommand of RunTestsCommands which runs instrumentation tests."""
  instrumentation_options = ProcessInstrumentationOptions(options, error_func)

  if len(devices) > 1 and options.wait_for_debugger:
    logging.warning('Debugger can not be sharded, using first available device')
    devices = devices[:1]

  results = base_test_result.TestRunResults()
  exit_code = 0

  if options.run_java_tests:
    runner_factory, tests = instrumentation_setup.Setup(instrumentation_options)

    test_results, exit_code = test_dispatcher.RunTests(
        tests, runner_factory, devices, shard=True, test_timeout=None,
        num_retries=options.num_retries)

    results.AddTestRunResults(test_results)

  if options.run_python_tests:
    runner_factory, tests = host_driven_setup.InstrumentationSetup(
        options.host_driven_root, options.official_build,
        instrumentation_options)

    if tests:
      test_results, test_exit_code = test_dispatcher.RunTests(
          tests, runner_factory, devices, shard=True, test_timeout=None,
          num_retries=options.num_retries)

      results.AddTestRunResults(test_results)

      # Only allow exit code escalation
      if test_exit_code and exit_code != constants.ERROR_EXIT_CODE:
        exit_code = test_exit_code

  if options.device_flags:
    options.device_flags = os.path.join(constants.DIR_SOURCE_ROOT,
                                        options.device_flags)

  report_results.LogFull(
      results=results,
      test_type='Instrumentation',
      test_package=os.path.basename(options.test_apk),
      annotation=options.annotations,
      flakiness_server=options.flakiness_dashboard_server)

  return exit_code


def _RunUIAutomatorTests(options, error_func, devices):
  """Subcommand of RunTestsCommands which runs uiautomator tests."""
  uiautomator_options = ProcessUIAutomatorOptions(options, error_func)

  runner_factory, tests = uiautomator_setup.Setup(uiautomator_options)

  results, exit_code = test_dispatcher.RunTests(
      tests, runner_factory, devices, shard=True, test_timeout=None,
      num_retries=options.num_retries)

  report_results.LogFull(
      results=results,
      test_type='UIAutomator',
      test_package=os.path.basename(options.test_jar),
      annotation=options.annotations,
      flakiness_server=options.flakiness_dashboard_server)

  return exit_code


def _RunJUnitTests(options, error_func):
  """Subcommand of RunTestsCommand which runs junit tests."""
  junit_options = ProcessJUnitTestOptions(options, error_func)
  runner_factory, tests = junit_setup.Setup(junit_options)
  _, exit_code = junit_dispatcher.RunTests(tests, runner_factory)

  return exit_code


def _RunMonkeyTests(options, error_func, devices):
  """Subcommand of RunTestsCommands which runs monkey tests."""
  monkey_options = ProcessMonkeyTestOptions(options, error_func)

  runner_factory, tests = monkey_setup.Setup(monkey_options)

  results, exit_code = test_dispatcher.RunTests(
      tests, runner_factory, devices, shard=False, test_timeout=None,
      num_retries=options.num_retries)

  report_results.LogFull(
      results=results,
      test_type='Monkey',
      test_package='Monkey')

  return exit_code


def _RunPerfTests(options, args, error_func):
  """Subcommand of RunTestsCommands which runs perf tests."""
  perf_options = ProcessPerfTestOptions(options, args, error_func)

  # Just save a simple json with a list of test names.
  if perf_options.output_json_list:
    return perf_test_runner.OutputJsonList(
        perf_options.steps, perf_options.output_json_list)

  # Just print the results from a single previously executed step.
  if perf_options.print_step:
    return perf_test_runner.PrintTestOutput(perf_options.print_step)

  runner_factory, tests, devices = perf_setup.Setup(perf_options)

  # shard=False means that each device will get the full list of tests
  # and then each one will decide their own affinity.
  # shard=True means each device will pop the next test available from a queue,
  # which increases throughput but have no affinity.
  results, _ = test_dispatcher.RunTests(
      tests, runner_factory, devices, shard=False, test_timeout=None,
      num_retries=options.num_retries)

  report_results.LogFull(
      results=results,
      test_type='Perf',
      test_package='Perf')

  if perf_options.single_step:
    return perf_test_runner.PrintTestOutput('single_step')

  perf_test_runner.PrintSummary(tests)

  # Always return 0 on the sharding stage. Individual tests exit_code
  # will be returned on the print_step stage.
  return 0


def _GetAttachedDevices(test_device=None):
  """Get all attached devices.

  Args:
    test_device: Name of a specific device to use.

  Returns:
    A list of attached devices.
  """
  attached_devices = []

  attached_devices = android_commands.GetAttachedDevices()
  if test_device:
    assert test_device in attached_devices, (
        'Did not find device %s among attached device. Attached devices: %s'
        % (test_device, ', '.join(attached_devices)))
    attached_devices = [test_device]

  assert attached_devices, 'No devices attached.'

  return sorted(attached_devices)


def RunTestsCommand(command, options, args, option_parser):
  """Checks test type and dispatches to the appropriate function.

  Args:
    command: String indicating the command that was received to trigger
        this function.
    options: optparse options dictionary.
    args: List of extra args from optparse.
    option_parser: optparse.OptionParser object.

  Returns:
    Integer indicated exit code.

  Raises:
    Exception: Unknown command name passed in, or an exception from an
        individual test runner.
  """

  # Check for extra arguments
  if len(args) > 2 and command != 'perf':
    option_parser.error('Unrecognized arguments: %s' % (' '.join(args[2:])))
    return constants.ERROR_EXIT_CODE
  if command == 'perf':
    if ((options.single_step and len(args) <= 2) or
        (not options.single_step and len(args) > 2)):
      option_parser.error('Unrecognized arguments: %s' % (' '.join(args)))
      return constants.ERROR_EXIT_CODE

  ProcessCommonOptions(options)

  devices = _GetAttachedDevices(options.test_device)

  forwarder.Forwarder.RemoveHostLog()
  if not ports.ResetTestServerPortAllocation():
    raise Exception('Failed to reset test server port.')

  if command == 'gtest':
    return _RunGTests(options, devices)
  elif command == 'linker':
    return _RunLinkerTests(options, devices)
  elif command == 'instrumentation':
    return _RunInstrumentationTests(options, option_parser.error, devices)
  elif command == 'uiautomator':
    return _RunUIAutomatorTests(options, option_parser.error, devices)
  elif command == 'junit':
    return _RunJUnitTests(options, option_parser.error)
  elif command == 'monkey':
    return _RunMonkeyTests(options, option_parser.error, devices)
  elif command == 'perf':
    return _RunPerfTests(options, args, option_parser.error)
  else:
    raise Exception('Unknown test type.')


def HelpCommand(command, _options, args, option_parser):
  """Display help for a certain command, or overall help.

  Args:
    command: String indicating the command that was received to trigger
        this function.
    options: optparse options dictionary. unused.
    args: List of extra args from optparse.
    option_parser: optparse.OptionParser object.

  Returns:
    Integer indicated exit code.
  """
  # If we don't have any args, display overall help
  if len(args) < 3:
    option_parser.print_help()
    return 0
  # If we have too many args, print an error
  if len(args) > 3:
    option_parser.error('Unrecognized arguments: %s' % (' '.join(args[3:])))
    return constants.ERROR_EXIT_CODE

  command = args[2]

  if command not in VALID_COMMANDS:
    option_parser.error('Unrecognized command.')

  # Treat the help command as a special case. We don't care about showing a
  # specific help page for itself.
  if command == 'help':
    option_parser.print_help()
    return 0

  VALID_COMMANDS[command].add_options_func(option_parser)
  option_parser.usage = '%prog ' + command + ' [options]'
  option_parser.commands_dict = {}
  option_parser.print_help()

  return 0


# Define a named tuple for the values in the VALID_COMMANDS dictionary so the
# syntax is a bit prettier. The tuple is two functions: (add options, run
# command).
CommandFunctionTuple = collections.namedtuple(
    'CommandFunctionTuple', ['add_options_func', 'run_command_func'])
VALID_COMMANDS = {
    'gtest': CommandFunctionTuple(AddGTestOptions, RunTestsCommand),
    'instrumentation': CommandFunctionTuple(
        AddInstrumentationTestOptions, RunTestsCommand),
    'uiautomator': CommandFunctionTuple(
        AddUIAutomatorTestOptions, RunTestsCommand),
    'junit': CommandFunctionTuple(
        AddJUnitTestOptions, RunTestsCommand),
    'monkey': CommandFunctionTuple(
        AddMonkeyTestOptions, RunTestsCommand),
    'perf': CommandFunctionTuple(
        AddPerfTestOptions, RunTestsCommand),
    'linker': CommandFunctionTuple(
        AddLinkerTestOptions, RunTestsCommand),
    'help': CommandFunctionTuple(lambda option_parser: None, HelpCommand)
    }


def DumpThreadStacks(_signal, _frame):
  for thread in threading.enumerate():
    reraiser_thread.LogThreadStack(thread)


def main():
  signal.signal(signal.SIGUSR1, DumpThreadStacks)
  option_parser = command_option_parser.CommandOptionParser(
      commands_dict=VALID_COMMANDS)
  return command_option_parser.ParseAndExecute(option_parser)


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