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import hci_packets as hci
import link_layer_packets as ll
import unittest
from hci_packets import ErrorCode
from py.bluetooth import Address
from py.controller import ControllerTest, Phy


class Test(ControllerTest):

    # Verify that the controller instance sends PING requests
    # to keep the connection alive, and triggers a supervision
    # timeout when no PING response is received.
    async def test_connection_keeplive(self):
        # Test parameters.
        peer_address = Address("aa:bb:cc:dd:ee:ff")
        controller = self.controller

        # Prelude: Establish an ACL connection as peripheral with the IUT.
        acl_connection_handle = await self.establish_le_connection_peripheral(
            peer_address
        )

        # The controller should send a PING request after a short timeout.
        await self.expect_ll(
            ll.PingRequest(
                destination_address=peer_address, source_address=controller.address
            )
        )
        controller.send_ll(
            ll.PingResponse(
                destination_address=controller.address, source_address=peer_address
            ),
            phy=Phy.LowEnergy,
        )

        # The controller should send another PING request after a short timeout.
        await self.expect_ll(
            ll.PingRequest(
                destination_address=peer_address, source_address=controller.address
            )
        )

        # Without any response from the peer device, the controller should trigger
        # a link supervision timeout.
        await self.expect_ll(
            ll.Disconnect(
                destination_address=peer_address,
                source_address=controller.address,
                reason=ErrorCode.CONNECTION_TIMEOUT,
            )
        )
        await self.expect_evt(
            hci.DisconnectionComplete(
                connection_handle=acl_connection_handle,
                status=ErrorCode.SUCCESS,
                reason=ErrorCode.CONNECTION_TIMEOUT,
            )
        )