# 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.

import contextlib
import logging
import os
import shutil
from six import StringIO
import socket
import subprocess
import tempfile
import time
import traceback

from oslo_utils import uuidutils

from selenium.webdriver.common import action_chains
from selenium.webdriver.common import by
from selenium.webdriver.common import keys
import testtools
import xvfbwrapper

from horizon.test import webdriver
from openstack_dashboard.test.integration_tests import config
from openstack_dashboard.test.integration_tests.pages import loginpage
from openstack_dashboard.test.integration_tests.regions import messages
from openstack_dashboard.test.integration_tests.video_recorder import \
    VideoRecorder

# Set logging level to DEBUG for all logger here
# so that lower level messages are output even before starting tests.
ROOT_LOGGER = logging.getLogger()
ROOT_LOGGER.setLevel(logging.DEBUG)

LOG = logging.getLogger(__name__)

IS_SELENIUM_HEADLESS = os.environ.get('SELENIUM_HEADLESS', False)
ROOT_PATH = os.path.dirname(os.path.abspath(config.__file__))

if not subprocess.call('which xdpyinfo > /dev/null 2>&1', shell=True):
    SCREEN_SIZE = subprocess.check_output('xdpyinfo | grep dimensions',
                                          shell=True).split()[1].split('x')
else:
    SCREEN_SIZE = (None, None)
    LOG.info("X11 isn't installed. Should use xvfb to run tests.")


def gen_random_resource_name(resource="", timestamp=True):
    """Generate random resource name using uuid and timestamp.

    Input fields are usually limited to 255 or 80 characters hence their
    provide enough space for quite long resource names, but it might be
    the case that maximum field length is quite restricted, it is then
    necessary to consider using shorter resource argument or avoid using
    timestamp by setting timestamp argument to False.
    """
    fields = ["horizon"]
    if resource:
        fields.append(resource)
    if timestamp:
        tstamp = time.strftime("%d-%m-%H-%M-%S")
        fields.append(tstamp)
    fields.append(uuidutils.generate_uuid(dashed=False))
    return "_".join(fields)


@contextlib.contextmanager
def gen_temporary_file(name='', suffix='.qcow2', size=10485760):
    """Generate temporary file with provided parameters.

    :param name: file name except the extension /suffix
    :param suffix: file extension/suffix
    :param size: size of the file to create, bytes are generated randomly
    :return: path to the generated file
    """
    with tempfile.NamedTemporaryFile(prefix=name, suffix=suffix) as tmp_file:
        tmp_file.write(os.urandom(size))
        yield tmp_file.name


class AssertsMixin(object):

    def assertSequenceTrue(self, actual):
        return self.assertEqual(list(actual), [True] * len(actual))

    def assertSequenceFalse(self, actual):
        return self.assertEqual(list(actual), [False] * len(actual))


class BaseTestCase(testtools.TestCase):

    CONFIG = config.get_config()

    def setUp(self):
        if not os.environ.get('INTEGRATION_TESTS', False):
            raise self.skipException(
                "The INTEGRATION_TESTS env variable is not set.")

        self._configure_log()

        self.addOnException(
            lambda exc_info: setattr(self, '_need_attach_test_log', True))

        def cleanup():
            if getattr(self, '_need_attach_test_log', None):
                self._attach_test_log()

        self.addCleanup(cleanup)

        width, height = SCREEN_SIZE
        display = '0.0'
        # Start a virtual display server for running the tests headless.
        if IS_SELENIUM_HEADLESS:
            width, height = 1920, 1080
            self.vdisplay = xvfbwrapper.Xvfb(width=width, height=height)
            args = []

            # workaround for memory leak in Xvfb taken from:
            # http://blog.jeffterrace.com/2012/07/xvfb-memory-leak-workaround.html
            args.append("-noreset")

            # disables X access control
            args.append("-ac")

            if hasattr(self.vdisplay, 'extra_xvfb_args'):
                # xvfbwrapper 0.2.8 or newer
                self.vdisplay.extra_xvfb_args.extend(args)
            else:
                self.vdisplay.xvfb_cmd.extend(args)
            self.vdisplay.start()
            display = self.vdisplay.new_display

            self.addCleanup(self.vdisplay.stop)

        self.video_recorder = VideoRecorder(width, height, display=display)
        self.video_recorder.start()

        self.addOnException(
            lambda exc_info: setattr(self, '_need_attach_video', True))

        def cleanup():
            self.video_recorder.stop()
            if getattr(self, '_need_attach_video', None):
                self._attach_video()
            else:
                self.video_recorder.clear()

        self.addCleanup(cleanup)

        # Increase the default Python socket timeout from nothing
        # to something that will cope with slow webdriver startup times.
        # This *just* affects the communication between this test process
        # and the webdriver.
        socket.setdefaulttimeout(60)
        # Start the Selenium webdriver and setup configuration.
        desired_capabilities = dict(webdriver.desired_capabilities)
        desired_capabilities['loggingPrefs'] = {'browser': 'ALL'}
        self.driver = webdriver.WebDriverWrapper(
            desired_capabilities=desired_capabilities
        )
        if self.CONFIG.selenium.maximize_browser:
            self.driver.maximize_window()
            if IS_SELENIUM_HEADLESS:  # force full screen in xvfb
                self.driver.set_window_size(width, height)

        self.driver.implicitly_wait(self.CONFIG.selenium.implicit_wait)
        self.driver.set_page_load_timeout(
            self.CONFIG.selenium.page_timeout)

        self.addOnException(self._attach_page_source)
        self.addOnException(self._attach_screenshot)
        self.addOnException(
            lambda exc_info: setattr(self, '_need_attach_browser_log', True))

        def cleanup():
            if getattr(self, '_need_attach_browser_log', None):
                self._attach_browser_log()
            self.driver.quit()

        self.addCleanup(cleanup)

        super(BaseTestCase, self).setUp()

    def addOnException(self, exception_handler):

        def wrapped_handler(exc_info):
            if issubclass(exc_info[0], testtools.testcase.TestSkipped):
                return
            return exception_handler(exc_info)

        super(BaseTestCase, self).addOnException(wrapped_handler)

    def _configure_log(self):
        """Configure log to capture test logs include selenium logs.

        This allows us to attach them if test will be broken.
        """
        # clear other handlers to set target handler
        ROOT_LOGGER.handlers[:] = []
        self._log_buffer = StringIO()
        stream_handler = logging.StreamHandler(stream=self._log_buffer)
        stream_handler.setLevel(logging.DEBUG)
        formatter = logging.Formatter(
            '%(asctime)s - %(name)s - %(levelname)s - %(message)s')
        stream_handler.setFormatter(formatter)
        ROOT_LOGGER.addHandler(stream_handler)

    @property
    def _test_report_dir(self):
        report_dir = os.path.join(ROOT_PATH, 'test_reports',
                                  '{}.{}'.format(self.__class__.__name__,
                                                 self._testMethodName))
        if not os.path.isdir(report_dir):
            os.makedirs(report_dir)
        return report_dir

    def _attach_page_source(self, exc_info):
        source_path = os.path.join(self._test_report_dir, 'page.html')
        with self.log_exception("Attach page source"):
            with open(source_path, 'w') as f:
                f.write(self._get_page_html_source())

    def _attach_screenshot(self, exc_info):
        screen_path = os.path.join(self._test_report_dir, 'screenshot.png')
        with self.log_exception("Attach screenshot"):
            self.driver.get_screenshot_as_file(screen_path)

    def _attach_video(self, exc_info=None):
        with self.log_exception("Attach video"):
            if not os.path.isfile(self.video_recorder.file_path):
                LOG.warning("Can't find video %s",
                            self.video_recorder.file_path)
                return

            shutil.move(self.video_recorder.file_path,
                        os.path.join(self._test_report_dir, 'video.mp4'))

    def _attach_browser_log(self, exc_info=None):
        browser_log_path = os.path.join(self._test_report_dir, 'browser.log')
        with self.log_exception("Attach browser log"):
            with open(browser_log_path, 'w') as f:
                f.write(
                    self._unwrap_browser_log(self.driver.get_log('browser')))

    def _attach_test_log(self, exc_info=None):
        test_log_path = os.path.join(self._test_report_dir, 'test.log')
        with self.log_exception("Attach test log"):
            with open(test_log_path, 'w') as f:
                f.write(self._log_buffer.getvalue().encode('utf-8'))

    @contextlib.contextmanager
    def log_exception(self, label):
        try:
            yield
        except Exception:
            self.addDetail(
                label, testtools.content.text_content(traceback.format_exc()))

    @staticmethod
    def _unwrap_browser_log(_log):
        def rec(log):
            if isinstance(log, dict):
                return log['message'].encode('utf-8')
            elif isinstance(log, list):
                return '\n'.join([rec(item) for item in log])
            else:
                return log.encode('utf-8')
        return rec(_log)

    def zoom_out(self, times=3):
        """Zooming out a specified element.

        It prevents different elements being driven out of xvfb viewport
        (which in Selenium>=2.50.1 prevents interaction with them).
        """
        html = self.driver.find_element(by.By.TAG_NAME, 'html')
        html.send_keys(keys.Keys.NULL)
        zoom_out_keys = (keys.Keys.SUBTRACT,) * times
        action_chains.ActionChains(self.driver).key_down(
            keys.Keys.CONTROL).send_keys(*zoom_out_keys).key_up(
            keys.Keys.CONTROL).perform()

    def _get_page_html_source(self):
        """Gets html page source.

        self.driver.page_source is not used on purpose because it does not
        display html code generated/changed by javascript.
        """
        html_elem = self.driver.find_element_by_tag_name("html")
        return html_elem.get_attribute("innerHTML").encode("utf-8")


class TestCase(BaseTestCase, AssertsMixin):

    TEST_USER_NAME = BaseTestCase.CONFIG.identity.username
    TEST_PASSWORD = BaseTestCase.CONFIG.identity.password
    HOME_PROJECT = BaseTestCase.CONFIG.identity.home_project

    def setUp(self):
        super(TestCase, self).setUp()
        self.login_pg = loginpage.LoginPage(self.driver, self.CONFIG)
        self.login_pg.go_to_login_page()
        # TODO(schipiga): lets check that tests work without viewport changing,
        # otherwise will uncomment.
        # self.zoom_out()
        self.home_pg = self.login_pg.login(self.TEST_USER_NAME,
                                           self.TEST_PASSWORD)
        self.home_pg.change_project(self.HOME_PROJECT)
        self.assertTrue(
            self.home_pg.find_message_and_dismiss(messages.SUCCESS))
        self.assertFalse(
            self.home_pg.find_message_and_dismiss(messages.ERROR))

        def cleanup():
            if self.home_pg.is_logged_in:
                self.home_pg.go_to_home_page()
                self.home_pg.log_out()

        self.addCleanup(cleanup)


class AdminTestCase(TestCase, AssertsMixin):

    TEST_USER_NAME = TestCase.CONFIG.identity.admin_username
    TEST_PASSWORD = TestCase.CONFIG.identity.admin_password
    HOME_PROJECT = BaseTestCase.CONFIG.identity.admin_home_project
