# Copyright (c) 2014 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
import os
import re
import time

import common
from autotest_lib.client.common_lib import error, global_config
from autotest_lib.client.common_lib.cros import retry
from autotest_lib.server.cros.dynamic_suite import frontend_wrappers
from autotest_lib.server.hosts import cros_host
from autotest_lib.server.hosts import cros_repair

from chromite.lib import timeout_util

AUTOTEST_INSTALL_DIR = global_config.global_config.get_config_value(
        'SCHEDULER', 'drone_installation_directory')

#'/usr/local/autotest'
SHADOW_CONFIG_PATH = '%s/shadow_config.ini' % AUTOTEST_INSTALL_DIR
ATEST_PATH = '%s/cli/atest' % AUTOTEST_INSTALL_DIR

# Sample output of fping that we are matching against, the fping command
# will return 10 lines but they will be one of these two formats.
# We want to get the IP address for the first line and not match the
# second line that has a non 0 %loss.
#192.168.231.100 : xmt/rcv/%loss = 10/10/0%, min/avg/max = 0.68/0.88/1.13
#192.168.231.102 : xmt/rcv/%loss = 10/0/100%
SUBNET_DUT_SEARCH_RE = (r'(?P<ip>192.168.231.1[0-1][0-9]) : '
                        'xmt\/rcv\/%loss = [0-9]+\/[0-9]+\/0%')

MOBLAB_HOME = '/home/moblab'
MOBLAB_BOTO_LOCATION = '%s/.boto' % MOBLAB_HOME
MOBLAB_LAUNCH_CONTROL_KEY_LOCATION = '%s/.launch_control_key' % MOBLAB_HOME
MOBLAB_SERVICE_ACCOUNT_LOCATION = '%s/.service_account.json' % MOBLAB_HOME
MOBLAB_AUTODIR = '/usr/local/autodir'
DHCPD_LEASE_FILE = '/var/lib/dhcp/dhcpd.leases'
MOBLAB_SERVICES = ['moblab-scheduler-init',
                   'moblab-database-init',
                   'moblab-devserver-init',
                   'moblab-gsoffloader-init',
                   'moblab-gsoffloader_s-init']
MOBLAB_PROCESSES = ['apache2', 'dhcpd']
DUT_VERIFY_SLEEP_SECS = 5
DUT_VERIFY_TIMEOUT = 15 * 60
MOBLAB_TMP_DIR = '/mnt/moblab/tmp'
MOBLAB_PORT = 80


class UpstartServiceNotRunning(error.AutoservError):
    """An expected upstart service was not in the expected state."""

    def __init__(self, service_name):
        """Create us.
        @param service_name: Name of the service_name that was in the worng
                state.
        """
        super(UpstartServiceNotRunning, self).__init__(
                'Upstart service %s not in running state.' % service_name)


class MoblabHost(cros_host.CrosHost):
    """Moblab specific host class."""


    def _initialize_frontend_rpcs(self, timeout_min):
        """Initialize frontends for AFE and TKO for a moblab host.

        We tunnel all communication to the frontends through an SSH tunnel as
        many testing environments block everything except SSH access to the
        moblab DUT.

        @param timeout_min: The timeout minuties for AFE services.
        """
        web_address = self.rpc_server_tracker.tunnel_connect(MOBLAB_PORT)
        # Pass timeout_min to self.afe
        self.afe = frontend_wrappers.RetryingAFE(timeout_min=timeout_min,
                                                 user='moblab',
                                                 server=web_address)
        # Use default timeout_min of MoblabHost for self.tko
        self.tko = frontend_wrappers.RetryingTKO(timeout_min=self.timeout_min,
                                                 user='moblab',
                                                 server=web_address)


    def _initialize(self, *args, **dargs):
        super(MoblabHost, self)._initialize(*args, **dargs)
        # TODO(jrbarnette):  Our superclass already initialized
        # _repair_strategy, and now we're re-initializing it here.
        # That's awkward, if not actually wrong.
        self._repair_strategy = cros_repair.create_moblab_repair_strategy()
        self.timeout_min = dargs.get('rpc_timeout_min', 1)
        self._initialize_frontend_rpcs(self.timeout_min)


    @staticmethod
    def check_host(host, timeout=10):
        """
        Check if the given host is an moblab host.

        @param host: An ssh host representing a device.
        @param timeout: The timeout for the run command.


        @return: True if the host device has adb.

        @raises AutoservRunError: If the command failed.
        @raises AutoservSSHTimeout: Ssh connection has timed out.
        """
        try:
            result = host.run(
                    'grep -q moblab /etc/lsb-release && '
                    '! test -f /mnt/stateful_partition/.android_tester',
                    ignore_status=True, timeout=timeout)
        except (error.AutoservRunError, error.AutoservSSHTimeout):
            return False
        return result.exit_status == 0


    def install_boto_file(self, boto_path=''):
        """Install a boto file on the Moblab device.

        @param boto_path: Path to the boto file to install. If None, sends the
                          boto file in the current HOME directory.

        @raises error.TestError if the boto file does not exist.
        """
        if not boto_path:
            boto_path = os.path.join(os.getenv('HOME'), '.boto')
        if not os.path.exists(boto_path):
            raise error.TestError('Boto File:%s does not exist.' % boto_path)
        self.send_file(boto_path, MOBLAB_BOTO_LOCATION)
        self.run('chown moblab:moblab %s' % MOBLAB_BOTO_LOCATION)


    def get_autodir(self):
        """Return the directory to install autotest for client side tests."""
        return self.autodir or MOBLAB_AUTODIR


    def run_as_moblab(self, command, **kwargs):
        """Moblab commands should be ran as the moblab user not root.

        @param command: Command to run as user moblab.
        """
        command = "su - moblab -c '%s'" % command
        return self.run(command, **kwargs)


    def wait_afe_up(self, timeout_min=5):
        """Wait till the AFE is up and loaded.

        Attempt to reach the Moblab's AFE and database through its RPC
        interface.

        @param timeout_min: Minutes to wait for the AFE to respond. Default is
                            5 minutes.

        @raises urllib2.HTTPError if AFE does not respond within the timeout.
        """
        # Use moblabhost's own AFE object with a longer timeout to wait for the
        # AFE to load. Also re-create the ssh tunnel for connections to moblab.
        # Set the timeout_min to be longer than self.timeout_min for rebooting.
        self._initialize_frontend_rpcs(timeout_min)
        # Verify the AFE can handle a simple request.
        self._check_afe()
        # Reset the timeout_min after rebooting checks for afe services.
        self.afe.set_timeout(self.timeout_min)


    def add_dut(self, hostname):
        """Add a DUT hostname to the AFE.

        @param hostname: DUT hostname to add.
        """
        result = self.run_as_moblab('%s host create %s' % (ATEST_PATH,
                                                           hostname))
        logging.debug('atest host create output for host %s:\n%s',
                      hostname, result.stdout)


    def find_and_add_duts(self):
        """Discover DUTs on the testing subnet and add them to the AFE.

        Pings the range of IP's a DUT might be assigned by moblab, then
        parses the output to discover connected DUTs, connected means
        they have 0% dropped pings.
        If they are not already in the AFE, adds them to AFE.
        """
        existing_hosts = [host.hostname for host in self.afe.get_hosts()]
        fping_result = self.run('fping -g 192.168.231.100 192.168.231.110 '
                                '-a -c 10 -p 30 -q', ignore_status=True)
        for line in fping_result.stderr.splitlines():
            match = re.match(SUBNET_DUT_SEARCH_RE, line)
            if match:
                dut_ip = match.group('ip')
                if dut_ip in existing_hosts:
                    break
                self.add_dut(dut_ip)


    def verify_software(self):
        """Create the autodir then do standard verify."""
        # In case cleanup or powerwash wiped the autodir, create an empty
        # directory.
        # Removing this mkdir command will result in the disk size check
        # not being performed.
        self.run('mkdir -p %s' % MOBLAB_AUTODIR)
        super(MoblabHost, self).verify_software()


    def _verify_upstart_service(self, service, timeout_m):
        """Verify that the given moblab service is running.

        @param service: The upstart service to check for.
        @timeout_m: Timeout (in minuts) before giving up.
        @raises TimeoutException or UpstartServiceNotRunning if service isn't
                running.
        """
        @retry.retry(error.AutoservError, timeout_min=timeout_m, delay_sec=10)
        def _verify():
            if not self.upstart_status(service):
                raise UpstartServiceNotRunning(service)
        _verify()

    def verify_moblab_services(self, timeout_m):
        """Verify the required Moblab services are up and running.

        @param timeout_m: Timeout (in minutes) for how long to wait for services
                to start. Actual time taken may be slightly more than this.
        @raises AutoservError if any moblab service is not running.
        """
        if not MOBLAB_SERVICES:
            return

        service = MOBLAB_SERVICES[0]
        try:
            # First service can take a long time to start, especially on first
            # boot where container setup can take 5-10 minutes, depending on the
            # device.
            self._verify_upstart_service(service, timeout_m)
        except error.TimeoutException:
            raise UpstartServiceNotRunning(service)

        for service in MOBLAB_SERVICES[1:]:
            try:
                # Follow up services should come up quickly.
                self._verify_upstart_service(service, 0.5)
            except error.TimeoutException:
                raise UpstartServiceNotRunning(service)

        for process in MOBLAB_PROCESSES:
            try:
                self.run('pgrep %s' % process)
            except error.AutoservRunError:
                raise error.AutoservError('Moblab process: %s is not running.'
                                          % process)


    def _check_afe(self):
        """Verify whether afe of moblab works before verifying its DUTs.

        Verifying moblab sometimes happens after a successful provision, in
        which case moblab is restarted but tunnel of afe is not re-connected.
        This func is used to check whether afe is working now.

        @return True if afe works.
        @raises error.AutoservError if AFE is down; other exceptions are passed
                through.
        """
        try:
            self.afe.get_hosts()
        except (error.TimeoutException, timeout_util.TimeoutError) as e:
            raise error.AutoservError('Moblab AFE is not responding: %s' %
                                      str(e))
        except Exception as e:
            logging.error('Unknown exception when checking moblab AFE: %s', e)
            raise

        return True


    def verify_duts(self):
        """Verify the Moblab DUTs are up and running.

        @raises AutoservError if no DUTs are in the Ready State.
        """
        hosts = self.afe.reverify_hosts()
        logging.debug('DUTs scheduled for reverification: %s', hosts)


    def verify_special_tasks_complete(self):
        """Wait till the special tasks on the moblab host are complete."""
        total_time = 0
        while (self.afe.get_special_tasks(is_complete=False) and
               total_time < DUT_VERIFY_TIMEOUT):
            total_time = total_time + DUT_VERIFY_SLEEP_SECS
            time.sleep(DUT_VERIFY_SLEEP_SECS)
        if not self.afe.get_hosts(status='Ready'):
            for host in self.afe.get_hosts():
                logging.error('DUT: %s Status: %s', host, host.status)
            raise error.AutoservError('Moblab has 0 Ready DUTs')


    def get_platform(self):
        """Determine the correct platform label for this host.

        For Moblab devices '_moblab' is appended.

        @returns a string representing this host's platform.
        """
        return super(MoblabHost, self).get_platform() + '_moblab'


    def make_tmp_dir(self, base=MOBLAB_TMP_DIR):
        """Creates a temporary directory.

        @param base: The directory where it should be created.

        @return Path to a newly created temporary directory.
        """
        self.run('mkdir -p %s' % base)
        return self.run('mktemp -d -p %s' % base).stdout.strip()


    def get_os_type(self):
        return 'moblab'