# 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.

from autotest_lib.client.common_lib import error
from autotest_lib.client.common_lib.cros.network import ping_runner
from autotest_lib.client.common_lib.cros.network import xmlrpc_datatypes
from autotest_lib.server import site_linux_system
from autotest_lib.server.cros.network import wifi_cell_test_base


class network_WiFi_CSA(wifi_cell_test_base.WiFiCellTestBase):
    """Test that the client vacates the channel after notification
    from the AP that it should switch channels. Note that not all clients
    support CSA (Channel Switch Announcement), but they generally should at
    least try to disconnect from the AP."""
    version = 1


    def parse_additional_arguments(self, commandline_args, additional_params):
        """Hook into super class to take control files parameters.

        @param commandline_args dict of parsed parameters from the autotest.
        @param additional_params list of dicts describing router configs.

        """
        self._configurations = additional_params


    def run_once(self):
        """Sets up a router, connects to it, then tests a channel switch."""
        for router_conf, alternate_channel in self._configurations:
            self.context.router.require_capabilities(
                  [site_linux_system.LinuxSystem.
                          CAPABILITY_SEND_MANAGEMENT_FRAME])
            self.context.configure(router_conf)
            assoc_params = xmlrpc_datatypes.AssociationParameters()
            assoc_params.ssid = self.context.router.get_ssid()
            self.context.assert_connect_wifi(assoc_params)
            ping_config = ping_runner.PingConfig(
                    self.context.get_wifi_addr(ap_num=0))
            client_mac = self.context.client.wifi_mac
            for _ in range(10):
                # Since the client might be in power-save, we are not
                # guaranteed it will hear this message the first time around.
                self.context.router.send_management_frame_on_ap(
                        'channel_switch', alternate_channel)

                # Test to see if the router received a deauth message from
                # the client.
                if self.context.router.detect_client_deauth(client_mac):
                    break

                # Otherwise detect the client leaving indirectly by measuring
                # client pings.  This should fail at some point.
                ping_config = ping_runner.PingConfig(
                        self.context.get_wifi_addr(ap_num=0),
                        count=3, ignore_status=True,
                        ignore_result=True)
                result = self.context.client.ping(ping_config)
                if result.loss > 60:
                    break
            else:
                raise error.TestFail('Client never lost connectivity')
            self.context.client.shill.disconnect(assoc_params.ssid)
            self.context.router.deconfig()