# Copyright (c) 2013 The Chromium OS 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, os, re

from autotest_lib.client.cros import constants
from autotest_lib.client.bin import utils
from telemetry.core import cros_interface, exceptions, util
from telemetry.internal.browser import browser_finder, browser_options
from telemetry.internal.browser import extension_to_load

Error = exceptions.Error


# Cached result of whether ARC is available on current device.
_arc_available = None


def is_arc_available():
    """Returns true if ARC is available on current device."""
    global _arc_available
    if _arc_available is not None:
        return _arc_available

    def _check_lsb_release():
        lsb_release = '/etc/lsb-release'
        if not os.path.exists(lsb_release):
            return False
        with open(lsb_release) as f:
            for line in f:
                if line.startswith('CHROMEOS_ARC_VERSION='):
                    return True
        return False

    _arc_available = _check_lsb_release()
    return _arc_available


if is_arc_available():
    from autotest_lib.client.common_lib.cros import arc_util


def NormalizeEmail(username):
    """Remove dots from username. Add @gmail.com if necessary.

    TODO(achuith): Get rid of this when crbug.com/358427 is fixed.

    @param username: username/email to be scrubbed.
    """
    parts = re.split('@', username)
    parts[0] = re.sub('\.', '', parts[0])

    if len(parts) == 1:
        parts.append('gmail.com')
    return '@'.join(parts)


class Chrome(object):
    """Wrapper for creating a telemetry browser instance with extensions."""


    BROWSER_TYPE_LOGIN = 'system'
    BROWSER_TYPE_GUEST = 'system-guest'


    def __init__(self, logged_in=True, extension_paths=[], autotest_ext=False,
                 is_component=True, num_tries=3, extra_browser_args=None,
                 clear_enterprise_policy=True, dont_override_profile=False,
                 disable_gaia_services=True, disable_default_apps = True,
                 auto_login=True, gaia_login=False,
                 username=None, password=None, gaia_id=None,
                 arc_mode=None, disable_arc_opt_in=True):
        """
        Constructor of telemetry wrapper.

        @param logged_in: Regular user (True) or guest user (False).
        @param extension_paths: path of unpacked extension to install.
        @param autotest_ext: Load a component extension with privileges to
                             invoke chrome.autotestPrivate.
        @param is_component: Whether extensions should be loaded as component
                             extensions.
        @param num_tries: Number of attempts to log in.
        @param extra_browser_args: Additional argument(s) to pass to the
                                   browser. It can be a string or a list.
        @param clear_enterprise_policy: Clear enterprise policy before
                                        logging in.
        @param dont_override_profile: Don't delete cryptohome before login.
                                      Telemetry will output a warning with this
                                      option.
        @param disable_gaia_services: For enterprise autotests, this option may
                                      be used to enable policy fetch.
        @param disable_default_apps: For tests that exercise default apps.
        @param auto_login: Does not login automatically if this is False.
                           Useful if you need to examine oobe.
        @param gaia_login: Logs in to real gaia.
        @param username: Log in using this username instead of the default.
        @param password: Log in using this password instead of the default.
        @param gaia_id: Log in using this gaia_id instead of the default.
        @param arc_mode: How ARC instance should be started.  Default is to not
                         start.
        @param disable_arc_opt_in: For opt in flow autotest. This option is used
                                   to disable the arc opt in flow.
        """
        self._autotest_ext_path = None
        if autotest_ext:
            self._autotest_ext_path = os.path.join(os.path.dirname(__file__),
                                                   'autotest_private_ext')
            extension_paths.append(self._autotest_ext_path)

        finder_options = browser_options.BrowserFinderOptions()
        if is_arc_available() and arc_util.should_start_arc(arc_mode):
            # TODO(achuith): Fix extra_browser_args, so that appending the
            # following flags to it is simpler.
            if disable_arc_opt_in:
                finder_options.browser_options.AppendExtraBrowserArgs(
                        arc_util.get_extra_chrome_flags())
            logged_in = True

        self._browser_type = (self.BROWSER_TYPE_LOGIN
                if logged_in else self.BROWSER_TYPE_GUEST)
        finder_options.browser_type = self.browser_type
        if extra_browser_args:
            finder_options.browser_options.AppendExtraBrowserArgs(
                    extra_browser_args)

        # TODO(achuith): Remove this after PFQ revs. crbug.com/603169.
        if logged_in:
            try:
                extensions_to_load = finder_options.extensions_to_load
                for path in extension_paths:
                    extension = extension_to_load.ExtensionToLoad(
                            path, self.browser_type, is_component=is_component)
                    extensions_to_load.append(extension)
                self._extensions_to_load = extensions_to_load
            except AttributeError:
              pass

        # finder options must be set before parse_args(), browser options must
        # be set before Create().
        # TODO(crbug.com/360890) Below MUST be '2' so that it doesn't inhibit
        # autotest debug logs
        finder_options.verbosity = 2
        finder_options.CreateParser().parse_args(args=[])
        b_options = finder_options.browser_options
        b_options.disable_component_extensions_with_background_pages = False
        b_options.create_browser_with_oobe = True
        b_options.clear_enterprise_policy = clear_enterprise_policy
        b_options.dont_override_profile = dont_override_profile
        b_options.disable_gaia_services = disable_gaia_services
        b_options.disable_default_apps = disable_default_apps
        b_options.disable_component_extensions_with_background_pages = disable_default_apps

        b_options.auto_login = auto_login
        b_options.gaia_login = gaia_login

        if is_arc_available() and not disable_arc_opt_in:
            arc_util.set_browser_options_for_opt_in(b_options)

        self.username = b_options.username if username is None else username
        self.password = b_options.password if password is None else password
        self.username = NormalizeEmail(self.username)
        b_options.username = self.username
        b_options.password = self.password
        # gaia_id will be added to telemetry code in chromium repository later
        try:
            self.gaia_id = b_options.gaia_id if gaia_id is None else gaia_id
            b_options.gaia_id = self.gaia_id
        except AttributeError:
            pass

        self.arc_mode = arc_mode

        if logged_in:
            try:
                extensions_to_load = b_options.extensions_to_load
                for path in extension_paths:
                    extension = extension_to_load.ExtensionToLoad(
                            path, self.browser_type, is_component=is_component)
                    extensions_to_load.append(extension)
                self._extensions_to_load = extensions_to_load
            except AttributeError:
              pass

        # Turn on collection of Chrome coredumps via creation of a magic file.
        # (Without this, Chrome coredumps are trashed.)
        open(constants.CHROME_CORE_MAGIC_FILE, 'w').close()

        for i in range(num_tries):
            try:
                browser_to_create = browser_finder.FindBrowser(finder_options)
                self._browser = browser_to_create.Create(finder_options)
                if is_arc_available():
                    if not disable_arc_opt_in:
                        arc_util.opt_in(self.browser)
                    arc_util.post_processing_after_browser(self)
                break
            except (exceptions.LoginException) as e:
                logging.error('Timed out logging in, tries=%d, error=%s',
                              i, repr(e))
                if i == num_tries-1:
                    raise


    def __enter__(self):
        return self


    def __exit__(self, *args):
        self.close()


    @property
    def browser(self):
        """Returns a telemetry browser instance."""
        return self._browser


    def get_extension(self, extension_path):
        """Fetches a telemetry extension instance given the extension path."""
        for ext in self._extensions_to_load:
            if extension_path == ext.path:
                return self.browser.extensions[ext]
        return None


    @property
    def autotest_ext(self):
        """Returns the autotest extension."""
        return self.get_extension(self._autotest_ext_path)


    @property
    def login_status(self):
        """Returns login status."""
        ext = self.autotest_ext
        if not ext:
            return None

        ext.ExecuteJavaScript('''
            window.__login_status = null;
            chrome.autotestPrivate.loginStatus(function(s) {
              window.__login_status = s;
            });
        ''')
        return ext.EvaluateJavaScript('window.__login_status')


    def get_visible_notifications(self):
        """Returns an array of visible notifications of Chrome.

        For specific type of each notification, please refer to Chromium's
        chrome/common/extensions/api/autotest_private.idl.
        """
        ext = self.autotest_ext
        if not ext:
            return None

        ext.ExecuteJavaScript('''
            window.__items = null;
            chrome.autotestPrivate.getVisibleNotifications(function(items) {
              window.__items  = items;
            });
        ''')
        if ext.EvaluateJavaScript('window.__items') is None:
            return None
        return ext.EvaluateJavaScript('window.__items')


    @property
    def browser_type(self):
        """Returns the browser_type."""
        return self._browser_type


    @staticmethod
    def did_browser_crash(func):
        """Runs func, returns True if the browser crashed, False otherwise.

        @param func: function to run.

        """
        try:
            func()
        except (Error):
            return True
        return False


    @staticmethod
    def wait_for_browser_restart(func):
        """Runs func, and waits for a browser restart.

        @param func: function to run.

        """
        _cri = cros_interface.CrOSInterface()
        pid = _cri.GetChromePid()
        Chrome.did_browser_crash(func)
        utils.poll_for_condition(lambda: pid != _cri.GetChromePid(), timeout=60)


    def wait_for_browser_to_come_up(self):
        """Waits for the browser to come up. This should only be called after a
        browser crash.
        """
        def _BrowserReady(cr):
            tabs = []  # Wrapper for pass by reference.
            if self.did_browser_crash(
                    lambda: tabs.append(cr.browser.tabs.New())):
                return False
            try:
                tabs[0].Close()
            except:
                # crbug.com/350941
                logging.error('Timed out closing tab')
            return True
        util.WaitFor(lambda: _BrowserReady(self), timeout=10)


    def close(self):
        """Closes the browser."""
        try:
            if is_arc_available():
                arc_util.pre_processing_before_close(self)
        finally:
            self._browser.Close()