#!/usr/bin/env vpython
# Copyright (c) 2015 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.

"""Utility library for running a startup profile on an Android device.

Sets up a device for cygprofile, disables sandboxing permissions, and sets up
support for web page replay, device forwarding, and fake certificate authority
to make runs repeatable.
"""

import argparse
import logging
import os
import shutil
import subprocess
import sys
import time

_SRC_PATH = os.path.join(os.path.dirname(__file__), os.pardir, os.pardir)
sys.path.append(os.path.join(_SRC_PATH, 'third_party', 'catapult', 'devil'))
from devil.android import apk_helper
from devil.android import device_errors
from devil.android import device_utils
from devil.android import flag_changer
from devil.android import forwarder
from devil.android.sdk import intent

sys.path.append(os.path.join(_SRC_PATH, 'build', 'android'))
import devil_chromium
from pylib import constants

sys.path.append(os.path.join(_SRC_PATH, 'tools', 'perf'))
from core import path_util
sys.path.append(path_util.GetTelemetryDir())
from telemetry.internal.util import webpagereplay_go_server
from telemetry.internal.util import binary_manager


class NoCyglogDataError(Exception):
  """An error used to indicate that no cyglog data was collected."""

  def __init__(self, value):
    super(NoCyglogDataError, self).__init__()
    self.value = value

  def __str__(self):
    return repr(self.value)


def _DownloadFromCloudStorage(bucket, sha1_file_name):
  """Download the given file based on a hash file."""
  cmd = ['download_from_google_storage', '--no_resume',
         '--bucket', bucket, '-s', sha1_file_name]
  print 'Executing command ' + ' '.join(cmd)
  process = subprocess.Popen(cmd)
  process.wait()
  if process.returncode != 0:
    raise Exception('Exception executing command %s' % ' '.join(cmd))


def _SimulateSwipe(device, x1, y1, x2, y2):
  """Simulates a swipe on a device from (x1, y1) to (x2, y2).

  Coordinates are in (device dependent) pixels, and the origin is at the upper
  left corner.
  The simulated swipe will take 300ms.

  Args:
    device: (device_utils.DeviceUtils) device to run the command on.
    x1, y1, x2, y2: (int) Coordinates.
  """
  args = [str(x) for x in (x1, y1, x2, y2)]
  device.RunShellCommand(['input', 'swipe'] + args)


class WprManager(object):
  """A utility to download a WPR archive, host it, and forward device ports to
  it.
  """

  _WPR_BUCKET = 'chrome-partner-telemetry'

  def __init__(self, wpr_archive, device, cmdline_file, package):
    self._device = device
    self._wpr_archive = wpr_archive
    self._wpr_archive_hash = wpr_archive + '.sha1'
    self._cmdline_file = cmdline_file
    self._wpr_server = None
    self._host_http_port = None
    self._host_https_port = None
    self._flag_changer = None
    self._package = package

  def Start(self):
    """Set up the device and host for WPR."""
    self.Stop()
    self._BringUpWpr()
    self._StartForwarder()

  def Stop(self):
    """Clean up the device and host's WPR setup."""
    self._StopForwarder()
    self._StopWpr()

  def __enter__(self):
    self.Start()

  def __exit__(self, unused_exc_type, unused_exc_val, unused_exc_tb):
    self.Stop()

  def _BringUpWpr(self):
    """Start the WPR server on the host and the forwarder on the device."""
    print 'Starting WPR on host...'
    _DownloadFromCloudStorage(self._WPR_BUCKET, self._wpr_archive_hash)
    if binary_manager.NeedsInit():
      binary_manager.InitDependencyManager([])
    self._wpr_server = webpagereplay_go_server.ReplayServer(
        self._wpr_archive, '127.0.0.1', 0, 0, replay_options=[])
    ports = self._wpr_server.StartServer()
    self._host_http_port = ports['http']
    self._host_https_port = ports['https']

  def _StopWpr(self):
    """ Stop the WPR and forwarder."""
    print 'Stopping WPR on host...'
    if self._wpr_server:
      self._wpr_server.StopServer()
      self._wpr_server = None

  def _StartForwarder(self):
    """Sets up forwarding of device ports to the host, and configures chrome
    to use those ports.
    """
    if not self._wpr_server:
      logging.warning('No host WPR server to forward to.')
      return
    print 'Starting device forwarder...'
    forwarder.Forwarder.Map([(0, self._host_http_port),
                             (0, self._host_https_port)],
                            self._device)
    device_http = forwarder.Forwarder.DevicePortForHostPort(
        self._host_http_port)
    device_https = forwarder.Forwarder.DevicePortForHostPort(
        self._host_https_port)
    self._flag_changer = flag_changer.FlagChanger(
        self._device, self._cmdline_file)
    self._flag_changer.AddFlags([
        '--host-resolver-rules=MAP * 127.0.0.1,EXCLUDE localhost',
        '--testing-fixed-http-port=%s' % device_http,
        '--testing-fixed-https-port=%s' % device_https,

        # Allows to selectively avoid certificate errors in Chrome. Unlike
        # --ignore-certificate-errors this allows exercising the HTTP disk cache
        # and avoids re-establishing socket connections. The value is taken from
        # the WprGo documentation at:
        # https://github.com/catapult-project/catapult/blob/master/web_page_replay_go/README.md
        '--ignore-certificate-errors-spki-list=' +
        'PhrPvGIaAMmd29hj8BCZOq096yj7uMpRNHpn5PDxI6I=',

        # The flag --ignore-certificate-errors-spki-list (above) requires
        # specifying the profile directory, otherwise it is silently ignored.
        '--user-data-dir=/data/data/{}'.format(self._package)])

  def _StopForwarder(self):
    """Shuts down the port forwarding service."""
    if self._flag_changer:
      print 'Restoring flags while stopping forwarder, but why?...'
      self._flag_changer.Restore()
      self._flag_changer = None
    print 'Stopping device forwarder...'
    forwarder.Forwarder.UnmapAllDevicePorts(self._device)


class AndroidProfileTool(object):
  """A utility for generating cygprofile data for chrome on andorid.

  Runs cygprofile_unittest found in output_directory, does profiling runs,
  and pulls the data to the local machine in output_directory/cyglog_data.
  """

  _DEVICE_CYGLOG_DIR = '/data/local/tmp/chrome/cyglog'

  TEST_URL = 'https://www.google.com/#hl=en&q=science'
  _WPR_ARCHIVE = os.path.join(
      os.path.dirname(__file__), 'memory_top_10_mobile_000.wprgo')

  def __init__(self, output_directory, host_cyglog_dir, use_wpr, urls,
               simulate_user):
    """Constructor.

    Args:
      output_directory: (str) Chrome build directory.
      host_cyglog_dir: (str) Where to store the profiles.
      use_wpr: (bool) Whether to use Web Page Replay.
      urls: (str) URLs to load. Have to be contained in the WPR archive if
                  use_wpr is True.
      simulate_user: (bool) Whether to simulate a user.
    """
    devices = device_utils.DeviceUtils.HealthyDevices()
    self._device = devices[0]
    self._cygprofile_tests = os.path.join(
        output_directory, 'cygprofile_unittests')
    self._host_cyglog_dir = host_cyglog_dir
    self._use_wpr = use_wpr
    self._urls = urls
    self._simulate_user = simulate_user
    self._SetUpDevice()

  def RunCygprofileTests(self):
    """Run the cygprofile unit tests suite on the device.

    Returns:
      The exit code for the tests.
    """
    device_path = '/data/local/tmp/cygprofile_unittests'
    self._device.PushChangedFiles([(self._cygprofile_tests, device_path)])
    try:
      self._device.RunShellCommand(device_path, check_return=True)
    except (device_errors.CommandFailedError,
            device_errors.DeviceUnreachableError):
      # TODO(jbudorick): Let the exception propagate up once clients can
      # handle it.
      logging.exception('Failure while running cygprofile_unittests:')
      return 1
    return 0

  def CollectProfile(self, apk, package_info):
    """Run a profile and collect the log files.

    Args:
      apk: The location of the chrome apk to profile.
      package_info: A PackageInfo structure describing the chrome apk,
                    as from pylib/constants.

    Returns:
      A list of cygprofile data files.

    Raises:
      NoCyglogDataError: No data was found on the device.
    """
    self._Install(apk)
    try:
      changer = self._SetChromeFlags(package_info)
      self._SetUpDeviceFolders()
      if self._use_wpr:
        with WprManager(self._WPR_ARCHIVE, self._device,
                        package_info.cmdline_file, package_info.package):
          self._RunProfileCollection(package_info, self._simulate_user)
      else:
        self._RunProfileCollection(package_info, self._simulate_user)
    finally:
      self._RestoreChromeFlags(changer)

    data = self._PullCyglogData()
    self._DeleteDeviceData()
    return data

  def _RunProfileCollection(self, package_info, simulate_user):
    """Runs the profile collection tasks.

    If |simulate_user| is True, then try to simulate a real user, with swiping.
    Also do a first load of the page instead of about:blank, in order to
    exercise the cache. This is not desirable with a page that only contains
    cachable resources, as in this instance the network code will not be called.

    Args:
      package_info: Which Chrome package to use.
      simulate_user: (bool) Whether to try to simulate a user interacting with
                     the browser.
    """
    initial_url = self._urls[0] if simulate_user else 'about:blank'
    # Start up chrome once with a page, just to get the one-off
    # activities out of the way such as apk resource extraction and profile
    # creation.
    self._StartChrome(package_info, initial_url)
    time.sleep(15)
    self._KillChrome(package_info)
    self._SetUpDeviceFolders()
    for url in self._urls:
      self._StartChrome(package_info, url)
      time.sleep(15)
      if simulate_user:
        # Down, down, up, up.
        _SimulateSwipe(self._device, 200, 700, 200, 300)
        _SimulateSwipe(self._device, 200, 700, 200, 300)
        _SimulateSwipe(self._device, 200, 700, 200, 1000)
        _SimulateSwipe(self._device, 200, 700, 200, 1000)
      time.sleep(30)
      self._KillChrome(package_info)

  def Cleanup(self):
    """Delete all local and device files left over from profiling. """
    self._DeleteDeviceData()
    self._DeleteHostData()

  def _Install(self, apk):
    """Installs Chrome.apk on the device.

    Args:
      apk: The location of the chrome apk to profile.
    """
    print 'Installing apk...'
    self._device.Install(apk)

  def _SetUpDevice(self):
    """When profiling, files are output to the disk by every process.  This
    means running without sandboxing enabled.
    """
    # We need to have adb root in order to pull cyglog data
    try:
      print 'Enabling root...'
      self._device.EnableRoot()
      # SELinux need to be in permissive mode, otherwise the process cannot
      # write the log files.
      print 'Putting SELinux in permissive mode...'
      self._device.RunShellCommand(['setenforce', '0'], check_return=True)
    except device_errors.CommandFailedError as e:
      # TODO(jbudorick) Handle this exception appropriately once interface
      #                 conversions are finished.
      logging.error(str(e))

  def _SetChromeFlags(self, package_info):
    print 'Setting Chrome flags...'
    changer = flag_changer.FlagChanger(
        self._device, package_info.cmdline_file)
    changer.AddFlags(['--no-sandbox', '--disable-fre'])
    return changer

  def _RestoreChromeFlags(self, changer):
    print 'Restoring Chrome flags...'
    if changer:
      changer.Restore()

  def _SetUpDeviceFolders(self):
    """Creates folders on the device to store cyglog data."""
    print 'Setting up device folders...'
    self._DeleteDeviceData()
    self._device.RunShellCommand(
        ['mkdir', '-p', str(self._DEVICE_CYGLOG_DIR)],
        check_return=True)

  def _DeleteDeviceData(self):
    """Clears out cyglog storage locations on the device. """
    self._device.RunShellCommand(
        ['rm', '-rf', str(self._DEVICE_CYGLOG_DIR)],
        check_return=True)

  def _StartChrome(self, package_info, url):
    print 'Launching chrome...'
    self._device.StartActivity(
        intent.Intent(package=package_info.package,
                      activity=package_info.activity,
                      data=url,
                      extras={'create_new_tab': True}),
        blocking=True, force_stop=True)

  def _KillChrome(self, package_info):
    self._device.KillAll(package_info.package)

  def _DeleteHostData(self):
    """Clears out cyglog storage locations on the host."""
    shutil.rmtree(self._host_cyglog_dir, ignore_errors=True)

  def _SetUpHostFolders(self):
    self._DeleteHostData()
    os.mkdir(self._host_cyglog_dir)

  def _PullCyglogData(self):
    """Pulls the cyglog data off of the device.

    Returns:
      A list of cyglog data files which were pulled.

    Raises:
      NoCyglogDataError: No data was found on the device.
    """
    print 'Pulling cyglog data...'
    self._SetUpHostFolders()
    self._device.PullFile(self._DEVICE_CYGLOG_DIR, self._host_cyglog_dir)
    files = os.listdir(self._host_cyglog_dir)

    if len(files) == 0:
      raise NoCyglogDataError('No cyglog data was collected')

    # Temporary workaround/investigation: if (for unknown reason) 'adb pull' of
    # the directory 'cyglog' into '.../Release/cyglog_data' produces
    # '...cyglog_data/cyglog/files' instead of the usual '...cyglog_data/files',
    # list the files deeper in the tree.
    cyglog_dir = self._host_cyglog_dir
    if (len(files) == 1) and (files[0] == 'cyglog'):
      cyglog_dir = os.path.join(self._host_cyglog_dir, 'cyglog')
      files = os.listdir(cyglog_dir)

    if len(files) == 0:
      raise NoCyglogDataError('No cyglog data was collected')

    return [os.path.join(cyglog_dir, x) for x in files]


def AddProfileCollectionArguments(parser):
  """Adds the profiling collection arguments to |parser|."""
  parser.add_argument(
      '--no-wpr', action='store_true', help='Don\'t use WPR.')
  parser.add_argument('--urls', type=str, help='URLs to load.',
                      default=[AndroidProfileTool.TEST_URL],
                      nargs='+')
  parser.add_argument(
      '--simulate-user', action='store_true', help='More realistic collection.')


def CreateArgumentParser():
  """Creates and return the argument parser."""
  parser = argparse.ArgumentParser()
  parser.add_argument(
      '--adb-path', type=os.path.realpath,
      help='adb binary')
  parser.add_argument(
      '--apk-path', type=os.path.realpath, required=True,
      help='APK to profile')
  parser.add_argument(
      '--output-directory', type=os.path.realpath, required=True,
      help='Chromium output directory (e.g. out/Release)')
  parser.add_argument(
      '--trace-directory', type=os.path.realpath,
      help='Directory in which cyglog traces will be stored. '
           'Defaults to <output-directory>/cyglog_data')
  AddProfileCollectionArguments(parser)
  return parser


def main():
  parser = CreateArgumentParser()
  args = parser.parse_args()

  devil_chromium.Initialize(
      output_directory=args.output_directory, adb_path=args.adb_path)

  apk = apk_helper.ApkHelper(args.apk_path)
  package_info = None
  for p in constants.PACKAGE_INFO.itervalues():
    if p.package == apk.GetPackageName():
      package_info = p
      break
  else:
    raise Exception('Unable to determine package info for %s' % args.apk_path)

  profiler = AndroidProfileTool(
      args.output_directory, host_cyglog_dir=args.trace_directory,
      use_wpr=not args.no_wpr, urls=args.urls, simulate_user=args.simulate_user)
  profiler.CollectProfile(args.apk_path, package_info)
  return 0


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