#!/usr/bin/env python3
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import unittest

import thread_cert
import config
import mle

LEADER = 1
SED_1 = 2

CHILD_TIMEOUT = 30

DEFAULT_POLL_PERIOD = CHILD_TIMEOUT - 4
"""The default poll period calculated by ot::Mac::DataPollSender::GetDefaultPollPeriod()."""

USER_POLL_PERIOD = CHILD_TIMEOUT // 3
"""The poll period explicitly set by this test for verifying enhanced keep-alive."""


class SED_EnhancedKeepAlive(thread_cert.TestCase):
    TOPOLOGY = {
        LEADER: {
            'version': '1.2'
        },
        SED_1: {
            'mode': '-',
            'version': '1.2',
        },
    }
    """All nodes are created with default configurations"""

    def test(self):
        self.nodes[SED_1].set_timeout(CHILD_TIMEOUT)
        self.nodes[SED_1].set_pollperiod(USER_POLL_PERIOD * 1000)

        self.nodes[LEADER].start()
        self.simulator.go(config.LEADER_STARTUP_DELAY)
        self.assertEqual(self.nodes[LEADER].get_state(), 'leader')

        self.nodes[SED_1].start()
        self.simulator.go(7)
        self.assertEqual(self.nodes[SED_1].get_state(), 'child')

        leader_messages = self.simulator.get_messages_sent_by(LEADER)
        sed_messages = self.simulator.get_messages_sent_by(SED_1)

        # 1 - Leader transmits MLE advertisements
        msg = leader_messages.next_mle_message(mle.CommandType.ADVERTISEMENT)
        msg.assertSentWithHopLimit(255)
        msg.assertSentToDestinationAddress('ff02::1')
        msg.assertMleMessageContainsTlv(mle.SourceAddress)
        msg.assertMleMessageContainsTlv(mle.LeaderData)
        msg.assertMleMessageContainsTlv(mle.Route64)

        # 2 - SED_1 begins attach process by sending a multicast MLE Parent Request
        msg = sed_messages.next_mle_message(mle.CommandType.PARENT_REQUEST)
        msg.assertSentWithHopLimit(255)
        msg.assertSentToDestinationAddress('ff02::2')
        msg.assertMleMessageContainsTlv(mle.Mode)
        msg.assertMleMessageContainsTlv(mle.Challenge)
        msg.assertMleMessageContainsTlv(mle.ScanMask)
        msg.assertMleMessageContainsTlv(mle.Version)
        self.assertGreaterEqual(msg.get_mle_message_tlv(mle.Version).version, config.THREAD_VERSION_1_2)

        scan_mask_tlv = msg.get_mle_message_tlv(mle.ScanMask)
        self.assertEqual(1, scan_mask_tlv.router)
        self.assertEqual(0, scan_mask_tlv.end_device)

        # 3 - Leader sends a MLE Parent Response
        msg = leader_messages.next_mle_message(mle.CommandType.PARENT_RESPONSE)
        msg.assertSentToNode(self.nodes[SED_1])
        msg.assertMleMessageContainsTlv(mle.SourceAddress)
        msg.assertMleMessageContainsTlv(mle.LeaderData)
        msg.assertMleMessageContainsTlv(mle.LinkLayerFrameCounter)
        msg.assertMleMessageContainsOptionalTlv(mle.MleFrameCounter)
        msg.assertMleMessageContainsTlv(mle.Response)
        msg.assertMleMessageContainsTlv(mle.Challenge)
        msg.assertMleMessageContainsTlv(mle.LinkMargin)
        msg.assertMleMessageContainsTlv(mle.Connectivity)
        msg.assertMleMessageContainsTlv(mle.Version)
        self.assertGreaterEqual(msg.get_mle_message_tlv(mle.Version).version, config.THREAD_VERSION_1_2)

        # 4 - SED_1 receives the MLE Parent Response and sends a Child ID Request
        msg = sed_messages.next_mle_message(mle.CommandType.CHILD_ID_REQUEST)
        msg.assertSentToNode(self.nodes[LEADER])
        msg.assertMleMessageContainsTlv(mle.Response)
        msg.assertMleMessageContainsTlv(mle.LinkLayerFrameCounter)
        msg.assertMleMessageContainsOptionalTlv(mle.MleFrameCounter)
        msg.assertMleMessageContainsTlv(mle.Mode)
        msg.assertMleMessageContainsTlv(mle.Timeout)
        msg.assertMleMessageContainsTlv(mle.Version)
        msg.assertMleMessageContainsTlv(mle.TlvRequest)
        self.assertGreaterEqual(msg.get_mle_message_tlv(mle.Version).version, config.THREAD_VERSION_1_2)

        # 5 - Leader responds with a Child ID Response
        msg = leader_messages.next_mle_message(mle.CommandType.CHILD_ID_RESPONSE)
        msg.assertSentToNode(self.nodes[SED_1])
        msg.assertMleMessageContainsTlv(mle.SourceAddress)
        msg.assertMleMessageContainsTlv(mle.LeaderData)
        msg.assertMleMessageContainsTlv(mle.Address16)
        msg.assertMleMessageContainsOptionalTlv(mle.NetworkData)
        msg.assertMleMessageContainsOptionalTlv(mle.Route64)
        msg.assertMleMessageContainsOptionalTlv(mle.AddressRegistration)

        leader_aloc = self.nodes[LEADER].get_addr_leader_aloc()
        self.assertTrue(self.nodes[SED_1].ping(leader_aloc, timeout=USER_POLL_PERIOD * 2))

        # 6 - Timeout Child
        self.nodes[SED_1].set_pollperiod(CHILD_TIMEOUT * 1000 * 4)
        self.simulator.go(CHILD_TIMEOUT + 1)
        self.assertEqual(self.nodes[SED_1].get_state(), 'child')
        self.assertFalse(self.nodes[SED_1].ping(leader_aloc, timeout=USER_POLL_PERIOD * 2))
        self.flush_all()

        self.nodes[SED_1].stop()
        self.nodes[SED_1].set_pollperiod(USER_POLL_PERIOD * 1000)
        self.nodes[SED_1].start()

        # 7 - Wait SED_1 to re-attach
        self.simulator.go(240)
        self.assertEqual(self.nodes[SED_1].get_state(), 'child')
        leader_messages = self.simulator.get_messages_sent_by(LEADER)
        msg = leader_messages.next_mle_message(mle.CommandType.CHILD_ID_RESPONSE)
        msg.assertSentToNode(self.nodes[SED_1])
        msg.assertMleMessageContainsTlv(mle.SourceAddress)
        msg.assertMleMessageContainsTlv(mle.LeaderData)
        msg.assertMleMessageContainsTlv(mle.Address16)
        msg.assertMleMessageContainsOptionalTlv(mle.NetworkData)
        msg.assertMleMessageContainsOptionalTlv(mle.Route64)
        msg.assertMleMessageContainsOptionalTlv(mle.AddressRegistration)
        self.assertTrue(self.nodes[SED_1].ping(leader_aloc, timeout=USER_POLL_PERIOD * 2))
        self.flush_all()

        # 8 - Verify enhanced keep-alive works
        self.nodes[SED_1].set_pollperiod(CHILD_TIMEOUT * 1000 * 4)
        self.simulator.go(CHILD_TIMEOUT // 2)
        self.assertEqual(self.nodes[SED_1].get_state(), 'child')
        non_exist_addr = leader_aloc.replace('fc00', 'fc12')
        self.assertFalse(self.nodes[SED_1].ping(non_exist_addr))
        self.simulator.go(CHILD_TIMEOUT // 2)
        self.nodes[SED_1].set_pollperiod(USER_POLL_PERIOD * 1000)
        self.assertTrue(self.nodes[SED_1].ping(leader_aloc, timeout=USER_POLL_PERIOD * 2))

        # 9 - Verify child resets keep-alive timer
        self.nodes[SED_1].set_pollperiod(DEFAULT_POLL_PERIOD * 1000)
        self.simulator.go(DEFAULT_POLL_PERIOD // 3 * 2)
        self.flush_all()
        self.nodes[SED_1].ping(leader_aloc, timeout=1)
        self.simulator.go(DEFAULT_POLL_PERIOD // 3 * 2)
        sed_messages = self.simulator.get_messages_sent_by(SED_1)
        self.assertEqual(sed_messages.next_data_poll(), None)


if __name__ == '__main__':
    unittest.main()