# Copyright 2017 The Cobalt Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""The base class for black box tests."""

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import logging
import time

from cobalt.tools.automated_testing import cobalt_runner
from cobalt.tools.automated_testing import webdriver_utils

selenium_exceptions = webdriver_utils.import_selenium_module(
    'common.exceptions')

# The following constants and logics are shared between this module and
# the JavaScript test environment. Anyone making changes here should also
# ensure necessary changes are made to testdata/black_box_js_test_utils.js
_TEST_STATUS_ELEMENT_NAME = 'black_box_test_status'
_JS_TEST_SUCCESS_MESSAGE = 'JavaScript_test_succeeded'
_JS_TEST_FAILURE_MESSAGE = 'JavaScript_test_failed'
_JS_TEST_SETUP_DONE_MESSAGE = 'JavaScript_setup_done'

POLL_UNTIL_WAIT_SECONDS = 30


class BlackBoxCobaltRunner(cobalt_runner.CobaltRunner):
  """Custom CobaltRunner made for BlackBoxTests' need."""

  class AssertException(Exception):
    """Raised when assert condition fails."""

  def __init__(self,
               launcher_params,
               url,
               log_file=None,
               target_params=None,
               success_message=None,
               poll_until_wait_seconds=POLL_UNTIL_WAIT_SECONDS,
               **kwargs):
    # For black box tests, don't log inline script warnings, we intend to
    # explicitly control timings for suspends and resumes, so we are not
    # concerned about a "suspend at the wrong time".
    if target_params is None:
      target_params = []
    target_params.append('--silence_inline_script_warnings')

    super().__init__(
        launcher_params,
        url,
        log_file,
        target_params,
        success_message,
        poll_until_wait_seconds=poll_until_wait_seconds,
        **kwargs)

    self.poll_until_wait_seconds = poll_until_wait_seconds

  def PollUntilFoundOrTestsFailedWithReconnects(self, css_selector):
    """Polls until an element is found.

    Args:
      css_selector: A CSS selector
    """
    start_time = time.time()
    while time.time() - start_time < self.poll_until_wait_seconds:
      is_failed = False
      try:
        if self.FindElements(css_selector):
          break
        is_failed = self.JSTestsFailed()
      except (cobalt_runner.CobaltRunner.AssertException,
              selenium_exceptions.NoSuchElementException,
              selenium_exceptions.NoSuchWindowException,
              selenium_exceptions.WebDriverException) as e:
        # If the page is reloaded, the webdriver client status becomes
        # stale and should be reconnected.
        logging.warning(e)
        self.ReconnectWebDriver()
        continue
      if is_failed:
        raise BlackBoxCobaltRunner.AssertException(
            'JS Test failed while waiting for ' + css_selector)
      time.sleep(0.25)

  def JSTestsSucceeded(self):
    """Check succeeded test assertion in HTML page."""

    # Call onTestEnd() in black_box_js_test_utils.js to unblock the waiting for
    # JavaScript test logic completion.
    self.PollUntilFound('[' + _TEST_STATUS_ELEMENT_NAME + ']')
    body_element = self.UniqueFind('body')
    return body_element.get_attribute(
        _TEST_STATUS_ELEMENT_NAME) == _JS_TEST_SUCCESS_MESSAGE

  def JSTestsFailed(self):
    """Check failed test assertion in HTML page."""

    # Call onTestEnd() in black_box_js_test_utils.js to unblock the waiting for
    # JavaScript test logic completion.
    body_element = self.UniqueFind('body')
    return body_element and body_element.get_attribute(
        _TEST_STATUS_ELEMENT_NAME) == _JS_TEST_FAILURE_MESSAGE

  def WaitForJSTestsSetup(self):
    """Poll setup status until JavaScript gives green light."""

    # Calling setupFinished() in black_box_js_test_utils.js to unblock the
    # waiting logic here.
    self.PollUntilFound(f'#{_JS_TEST_SETUP_DONE_MESSAGE}')