# Copyright (c) 2012 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.

import logging
import os

import android_commands
from chrome_test_server_spawner import SpawningServer
from flag_changer import FlagChanger
import lighttpd_server
import run_tests_helper

FORWARDER_PATH = '/data/local/tmp/forwarder'
# These ports must match up with the constants in net/test/test_server.cc
TEST_SERVER_SPAWNER_PORT = 8001
TEST_SERVER_PORT = 8002
TEST_SYNC_SERVER_PORT = 8003


class BaseTestRunner(object):
  """Base class for running tests on a single device.

  A subclass should implement RunTests() with no parameter, so that calling
  the Run() method will set up tests, run them and tear them down.
  """

  def __init__(self, device, shard_index):
    """
      Args:
        device: Tests will run on the device of this ID.
        shard_index: Index number of the shard on which the test suite will run.
    """
    self.device = device
    self.adb = android_commands.AndroidCommands(device=device)
    # Synchronize date/time between host and device. Otherwise same file on
    # host and device may have different timestamp which may cause
    # AndroidCommands.PushIfNeeded failed, or a test which may compare timestamp
    # got from http head and local time could be failed.
    self.adb.SynchronizeDateTime()
    self._http_server = None
    self._forwarder = None
    self._spawning_server = None
    self._spawner_forwarder = None
    self._forwarder_device_port = 8000
    self.forwarder_base_url = ('http://localhost:%d' %
        self._forwarder_device_port)
    self.flags = FlagChanger(self.adb)
    self.shard_index = shard_index

  def Run(self):
    """Calls subclass functions to set up tests, run them and tear them down.

    Returns:
      Test results returned from RunTests().
    """
    self.SetUp()
    try:
      return self.RunTests()
    finally:
      self.TearDown()

  def SetUp(self):
    """Called before tests run."""
    pass

  def RunTests(self):
    """Runs the tests. Need to be overridden."""
    raise NotImplementedError

  def TearDown(self):
    """Called when tests finish running."""
    self.ShutdownHelperToolsForTestSuite()

  def CopyTestData(self, test_data_paths, dest_dir):
    """Copies |test_data_paths| list of files/directories to |dest_dir|.

    Args:
      test_data_paths: A list of files or directories relative to |dest_dir|
          which should be copied to the device. The paths must exist in
          |CHROME_DIR|.
      dest_dir: Absolute path to copy to on the device.
    """
    for p in test_data_paths:
      self.adb.PushIfNeeded(
          os.path.join(run_tests_helper.CHROME_DIR, p),
          os.path.join(dest_dir, p))

  def LaunchTestHttpServer(self, document_root, extra_config_contents=None):
    """Launches an HTTP server to serve HTTP tests.

    Args:
      document_root: Document root of the HTTP server.
      extra_config_contents: Extra config contents for the HTTP server.
    """
    self._http_server = lighttpd_server.LighttpdServer(
        document_root, extra_config_contents=extra_config_contents)
    if self._http_server.StartupHttpServer():
      logging.info('http server started: http://localhost:%s',
                   self._http_server.port)
    else:
      logging.critical('Failed to start http server')
    # Root access needed to make the forwarder executable work.
    self.adb.EnableAdbRoot()
    self.StartForwarderForHttpServer()

  def StartForwarderForHttpServer(self):
    """Starts a forwarder for the HTTP server.

    The forwarder forwards HTTP requests and responses between host and device.
    """
    # Sometimes the forwarder device port may be already used. We have to kill
    # all forwarder processes to ensure that the forwarder can be started since
    # currently we can not associate the specified port to related pid.
    # TODO(yfriedman/wangxianzhu): This doesn't work as most of the time the
    # port is in use but the forwarder is already dead. Killing all forwarders
    # is overly destructive and breaks other tests which make use of forwarders.
    # if IsDevicePortUsed(self.adb, self._forwarder_device_port):
    #   self.adb.KillAll('forwarder')
    self._forwarder = run_tests_helper.ForwardDevicePorts(
        self.adb, [(self._forwarder_device_port, self._http_server.port)])

  def RestartHttpServerForwarderIfNecessary(self):
    """Restarts the forwarder if it's not open."""
    # Checks to see if the http server port is being used.  If not forwards the
    # request.
    # TODO(dtrainor): This is not always reliable because sometimes the port
    # will be left open even after the forwarder has been killed.
    if not run_tests_helper.IsDevicePortUsed(self.adb,
        self._forwarder_device_port):
      self.StartForwarderForHttpServer()

  def ShutdownHelperToolsForTestSuite(self):
    """Shuts down the server and the forwarder."""
    # Forwarders should be killed before the actual servers they're forwarding
    # to as they are clients potentially with open connections and to allow for
    # proper hand-shake/shutdown.
    if self._forwarder or self._spawner_forwarder:
      # Kill all forwarders on the device and then kill the process on the host
      # (if it exists)
      self.adb.KillAll('forwarder')
      if self._forwarder:
        self._forwarder.kill()
      if self._spawner_forwarder:
        self._spawner_forwarder.kill()
    if self._http_server:
      self._http_server.ShutdownHttpServer()
    if self._spawning_server:
      self._spawning_server.Stop()
    self.flags.Restore()

  def LaunchChromeTestServerSpawner(self):
    """Launches test server spawner."""
    self._spawning_server = SpawningServer(TEST_SERVER_SPAWNER_PORT,
                                          TEST_SERVER_PORT)
    self._spawning_server.Start()
    # TODO(yfriedman): Ideally we'll only try to start up a port forwarder if
    # there isn't one already running but for now we just get an error message
    # and the existing forwarder still works.
    self._spawner_forwarder = run_tests_helper.ForwardDevicePorts(
        self.adb, [(TEST_SERVER_SPAWNER_PORT, TEST_SERVER_SPAWNER_PORT),
                   (TEST_SERVER_PORT, TEST_SERVER_PORT)])