"""
Module to interact with the ChromeCast via protobuf-over-socket.

Big thanks goes out to Fred Clift <fred@clift.org> who build the first
version of this code: https://github.com/minektur/chromecast-python-poc.
Without him this would not have been possible.
"""
# Pylint does not understand the protobuf objects correctly
# pylint: disable=no-member, too-many-lines

import errno
import json
import logging
import select
import socket
import ssl
import sys
import threading
import time
from collections import namedtuple
from struct import pack, unpack

from . import cast_channel_pb2
from .controllers import BaseController
from .controllers.media import MediaController
from .const import CAST_TYPE_AUDIO, CAST_TYPE_CHROMECAST, CAST_TYPE_GROUP
from .discovery import get_info_from_service, get_host_from_service_info
from .error import (
    ChromecastConnectionError,
    UnsupportedNamespace,
    NotConnected,
    PyChromecastStopped,
)

NS_CONNECTION = "urn:x-cast:com.google.cast.tp.connection"
NS_RECEIVER = "urn:x-cast:com.google.cast.receiver"
NS_HEARTBEAT = "urn:x-cast:com.google.cast.tp.heartbeat"

PLATFORM_DESTINATION_ID = "receiver-0"

MESSAGE_TYPE = "type"
TYPE_PING = "PING"
TYPE_RECEIVER_STATUS = "RECEIVER_STATUS"
TYPE_PONG = "PONG"
TYPE_CONNECT = "CONNECT"
TYPE_CLOSE = "CLOSE"
TYPE_GET_STATUS = "GET_STATUS"
TYPE_LAUNCH = "LAUNCH"
TYPE_LAUNCH_ERROR = "LAUNCH_ERROR"
TYPE_LOAD = "LOAD"

# The socket connection is being setup
CONNECTION_STATUS_CONNECTING = "CONNECTING"
# The socket connection was complete
CONNECTION_STATUS_CONNECTED = "CONNECTED"
# The socket connection has been disconnected
CONNECTION_STATUS_DISCONNECTED = "DISCONNECTED"
# Connecting to socket failed (after a CONNECTION_STATUS_CONNECTING)
CONNECTION_STATUS_FAILED = "FAILED"
# Failed to resolve service name
CONNECTION_STATUS_FAILED_RESOLVE = "FAILED_RESOLVE"
# The socket connection was lost and needs to be retried
CONNECTION_STATUS_LOST = "LOST"

APP_ID = "appId"
REQUEST_ID = "requestId"
SESSION_ID = "sessionId"
ERROR_REASON = "reason"

HB_PING_TIME = 10
HB_PONG_TIME = 10
POLL_TIME_BLOCKING = 5.0
POLL_TIME_NON_BLOCKING = 0.01
TIMEOUT_TIME = 30
RETRY_TIME = 5


class InterruptLoop(Exception):
    """ The chromecast has been manually stopped. """


def _dict_from_message_payload(message):
    """ Parses a PB2 message as a JSON dict. """
    try:
        data = json.loads(message.payload_utf8)
        if not isinstance(data, dict):
            logger = logging.getLogger(__name__)
            logger.debug(
                "Non dict json in namespace %s: '%s'",
                message.namespace,
                message.payload_utf8,
            )
            return {}
        return data
    except ValueError:
        logger = logging.getLogger(__name__)
        logger.debug(
            "Invalid json in namespace %s: '%s'",
            message.namespace,
            message.payload_utf8,
        )
        return {}


def _message_to_string(message, data=None):
    """ Gives a string representation of a PB2 message. """
    if data is None:
        data = _dict_from_message_payload(message)

    return "Message {} from {} to {}: {}".format(
        message.namespace,
        message.source_id,
        message.destination_id,
        data or message.payload_utf8,
    )


if sys.version_info >= (3, 0):

    def _json_to_payload(data):
        """ Encodes a python value into JSON format. """
        return json.dumps(data, ensure_ascii=False).encode("utf8")


else:

    def _json_to_payload(data):
        """ Encodes a python value into JSON format. """
        return json.dumps(data, ensure_ascii=False)


def _is_ssl_timeout(exc):
    """ Returns True if the exception is for an SSL timeout """
    return exc.message in (
        "The handshake operation timed out",
        "The write operation timed out",
        "The read operation timed out",
    )


NetworkAddress = namedtuple("NetworkAddress", ["address", "port"])

ConnectionStatus = namedtuple("ConnectionStatus", ["status", "address"])

CastStatus = namedtuple(
    "CastStatus",
    [
        "is_active_input",
        "is_stand_by",
        "volume_level",
        "volume_muted",
        "app_id",
        "display_name",
        "namespaces",
        "session_id",
        "transport_id",
        "status_text",
        "icon_url",
    ],
)

LaunchFailure = namedtuple("LaunchStatus", ["reason", "app_id", "request_id"])


# pylint: disable=too-many-instance-attributes
class SocketClient(threading.Thread):
    """
    Class to interact with a Chromecast through a socket.

    :param host: The host to connect to.
    :param port: The port to use when connecting to the device, set to None to
                 use the default of 8009. Special devices such as Cast Groups
                 may return a different port number so we need to use that.
    :param cast_type: The type of chromecast to connect to, see
                      dial.CAST_TYPE_* for types.
    :param tries: Number of retries to perform if the connection fails.
                  None for inifinite retries.
    :param timeout: A floating point number specifying the socket timeout in
                    seconds. None means to use the default which is 30 seconds.
    :param retry_wait: A floating point number specifying how many seconds to
                       wait between each retry. None means to use the default
                       which is 5 seconds.
    :param services: A list of mDNS services to try to connect to. If present,
                     parameters host and port are ignored and host and port are
                     instead resolved through mDNS. The list of services may be
                     modified, for example if speaker group leadership is handed
                     over. SocketClient will catch modifications to the list when
                     attempting reconnect.
    :param zconf: A zeroconf instance, needed if a list of services is passed.
                  The zeroconf instance may be obtained from the browser returned by
                  pychromecast.start_discovery().
    """

    def __init__(self, host, port=None, cast_type=CAST_TYPE_CHROMECAST, **kwargs):
        tries = kwargs.pop("tries", None)
        timeout = kwargs.pop("timeout", None)
        retry_wait = kwargs.pop("retry_wait", None)
        services = kwargs.pop("services", None)
        zconf = kwargs.pop("zconf", None)

        super(SocketClient, self).__init__()

        self.daemon = True

        self.logger = logging.getLogger(__name__)

        self._force_recon = False

        self.cast_type = cast_type
        self.fn = None  # pylint:disable=invalid-name
        self.tries = tries
        self.timeout = timeout or TIMEOUT_TIME
        self.retry_wait = retry_wait or RETRY_TIME
        self.host = host
        self.services = services or [None]
        self.zconf = zconf
        self.port = port or 8009

        self.source_id = "sender-0"
        self.stop = threading.Event()
        # socketpair used to interrupt the worker thread
        self.socketpair = socket.socketpair()

        self.app_namespaces = []
        self.destination_id = None
        self.session_id = None
        self._request_id = 0
        # dict mapping requestId on threading.Event objects
        self._request_callbacks = {}
        self._open_channels = []

        self.connecting = True
        self.first_connection = True
        self.socket = None

        # dict mapping namespace on Controller objects
        self._handlers = {}
        self._connection_listeners = []

        self.receiver_controller = ReceiverController(cast_type)
        self.media_controller = MediaController()
        self.heartbeat_controller = HeartbeatController()

        self.register_handler(self.heartbeat_controller)
        self.register_handler(ConnectionController())
        self.register_handler(self.receiver_controller)
        self.register_handler(self.media_controller)

        self.receiver_controller.register_status_listener(self)

    def initialize_connection(
        self,
    ):  # noqa: E501 pylint:disable=too-many-statements, too-many-branches
        """Initialize a socket to a Chromecast, retrying as necessary."""
        tries = self.tries

        if self.socket is not None:
            self.socket.close()
            self.socket = None

        # Make sure nobody is blocking.
        for callback in self._request_callbacks.values():
            callback["event"].set()

        self.app_namespaces = []
        self.destination_id = None
        self.session_id = None
        self._request_id = 0
        self._request_callbacks = {}
        self._open_channels = []

        self.connecting = True
        retry_log_fun = self.logger.error

        # Dict keeping track of individual retry delay for each named service
        retries = {}

        def mdns_backoff(service, retry):
            """Exponentional backoff for service name mdns lookups."""
            now = time.time()
            retry["next_retry"] = now + retry["delay"]
            retry["delay"] = min(retry["delay"] * 2, 300)
            retries[service] = retry

        while not self.stop.is_set() and (
            tries is None or tries > 0
        ):  # noqa: E501 pylint:disable=too-many-nested-blocks
            # Prune retries dict
            retries = {
                key: retries[key]
                for key in self.services
                if (key is not None and key in retries)
            }

            for service in self.services.copy():
                now = time.time()
                retry = retries.get(
                    service, {"delay": self.retry_wait, "next_retry": now}
                )
                # If we're connecting to a named service, check if it's time
                if service and now < retry["next_retry"]:
                    continue
                try:
                    self.socket = new_socket()
                    self.socket.settimeout(self.timeout)
                    self._report_connection_status(
                        ConnectionStatus(
                            CONNECTION_STATUS_CONNECTING,
                            NetworkAddress(self.host, self.port),
                        )
                    )
                    # Resolve the service name. If service is None, we're
                    # connecting directly to a host name or IP-address
                    if service:
                        host = None
                        port = None
                        service_info = get_info_from_service(service, self.zconf)
                        host, port = get_host_from_service_info(service_info)
                        if host and port:
                            try:
                                self.fn = service_info.properties[b"fn"].decode("utf-8")
                            except (AttributeError, KeyError, UnicodeError):
                                pass
                            self.logger.debug(
                                "[%s(%s):%s] Resolved service %s to %s:%s",
                                self.fn or "",
                                self.host,
                                self.port,
                                service,
                                host,
                                port,
                            )
                            self.host = host
                            self.port = port
                        else:
                            self.logger.debug(
                                "[%s(%s):%s] Failed to resolve service %s",
                                self.fn or "",
                                self.host,
                                self.port,
                                service,
                            )
                            self._report_connection_status(
                                ConnectionStatus(
                                    CONNECTION_STATUS_FAILED_RESOLVE,
                                    NetworkAddress(service, None),
                                )
                            )
                            mdns_backoff(service, retry)
                            # If zeroconf fails to receive the necessary data,
                            # try next service
                            continue

                    self.logger.debug(
                        "[%s(%s):%s] Connecting to %s:%s",
                        self.fn or "",
                        self.host,
                        self.port,
                        self.host,
                        self.port,
                    )
                    self.socket.connect((self.host, self.port))
                    self.socket = ssl.wrap_socket(self.socket)
                    self.connecting = False
                    self._force_recon = False
                    self._report_connection_status(
                        ConnectionStatus(
                            CONNECTION_STATUS_CONNECTED,
                            NetworkAddress(self.host, self.port),
                        )
                    )
                    self.receiver_controller.update_status()
                    self.heartbeat_controller.ping()
                    self.heartbeat_controller.reset()

                    if self.first_connection:
                        self.first_connection = False
                        self.logger.debug(
                            "[%s(%s):%s] Connected!",
                            self.fn or "",
                            self.host,
                            self.port,
                        )
                    else:
                        self.logger.info(
                            "[%s(%s):%s] Connection reestablished!",
                            self.fn or "",
                            self.host,
                            self.port,
                        )
                    return
                except OSError as err:
                    self.connecting = True
                    if self.stop.is_set():
                        self.logger.error(
                            "[%s(%s):%s] Failed to connect: %s. aborting due to stop signal.",
                            self.fn or "",
                            self.host,
                            self.port,
                            err,
                        )
                        raise ChromecastConnectionError("Failed to connect")

                    self._report_connection_status(
                        ConnectionStatus(
                            CONNECTION_STATUS_FAILED,
                            NetworkAddress(self.host, self.port),
                        )
                    )
                    if service is not None:
                        retry_log_fun(
                            "[%s(%s):%s] Failed to connect to service %s, retrying in %.1fs",
                            self.fn or "",
                            self.host,
                            self.port,
                            service,
                            retry["delay"],
                        )
                        mdns_backoff(service, retry)
                    else:
                        retry_log_fun(
                            "[%s(%s):%s] Failed to connect, retrying in %.1fs",
                            self.fn or "",
                            self.host,
                            self.port,
                            self.retry_wait,
                        )
                    retry_log_fun = self.logger.debug

            # Only sleep if we have another retry remaining
            if tries is None or tries > 1:
                self.logger.debug(
                    "[%s(%s):%s] Not connected, sleeping for %.1fs. Services: %s",
                    self.fn or "",
                    self.host,
                    self.port,
                    self.retry_wait,
                    self.services,
                )
                time.sleep(self.retry_wait)

            if tries:
                tries -= 1

        self.stop.set()
        self.logger.error(
            "[%s(%s):%s] Failed to connect. No retries.",
            self.fn or "",
            self.host,
            self.port,
        )
        raise ChromecastConnectionError("Failed to connect")

    def connect(self):
        """Connect socket connection to Chromecast device.

        Must only be called if the worker thread will not be started.
        """
        try:
            self.initialize_connection()
        except ChromecastConnectionError:
            self._report_connection_status(
                ConnectionStatus(
                    CONNECTION_STATUS_DISCONNECTED, NetworkAddress(self.host, self.port)
                )
            )
            return

    def disconnect(self):
        """ Disconnect socket connection to Chromecast device """
        self.stop.set()
        try:
            # Write to the socket to interrupt the worker thread
            self.socketpair[1].send(b"x")
        except socket.error:
            # The socketpair may already be closed during shutdown, ignore it
            pass

    def register_handler(self, handler):
        """ Register a new namespace handler. """
        self._handlers[handler.namespace] = handler

        handler.registered(self)

    def new_cast_status(self, cast_status):
        """ Called when a new cast status has been received. """
        new_channel = self.destination_id != cast_status.transport_id

        if new_channel:
            self.disconnect_channel(self.destination_id)

        self.app_namespaces = cast_status.namespaces
        self.destination_id = cast_status.transport_id
        self.session_id = cast_status.session_id

        if new_channel:
            # If any of the namespaces of the new app are supported
            # we will automatically connect to it to receive updates
            for namespace in self.app_namespaces:
                if namespace in self._handlers:
                    self._ensure_channel_connected(self.destination_id)
                    self._handlers[namespace].channel_connected()

    def _gen_request_id(self):
        """ Generates a unique request id. """
        self._request_id += 1

        return self._request_id

    @property
    def is_connected(self):
        """
        Returns True if the client is connected, False if it is stopped
        (or trying to connect).
        """
        return not self.connecting

    @property
    def is_stopped(self):
        """
        Returns True if the connection has been stopped, False if it is
        running.
        """
        return self.stop.is_set()

    def run(self):
        """ Connect to the cast and start polling the socket. """
        try:
            self.initialize_connection()
        except ChromecastConnectionError:
            self._report_connection_status(
                ConnectionStatus(
                    CONNECTION_STATUS_DISCONNECTED, NetworkAddress(self.host, self.port)
                )
            )
            return

        self.heartbeat_controller.reset()
        self._force_recon = False
        self.logger.debug("Thread started...")
        try:
            while not self.stop.is_set():
                if self.run_once(timeout=POLL_TIME_BLOCKING) == 1:
                    break
        except Exception:  # pylint: disable=broad-except
            self.logger.exception(
                ("[%s(%s):%s] Unhandled exception in worker thread"),
                self.fn or "",
                self.host,
                self.port,
            )
            raise

        self.logger.debug("Thread done...")
        # Clean up
        self._cleanup()

    def run_once(self, timeout=POLL_TIME_NON_BLOCKING):
        """
        Use run_once() in your own main loop after you
        receive something on the socket (get_socket()).
        """
        # pylint: disable=too-many-branches, too-many-return-statements

        try:
            if not self._check_connection():
                return 0
        except ChromecastConnectionError:
            return 1

        # poll the socket, as well as the socketpair to allow us to be interrupted
        rlist = [self.socket, self.socketpair[0]]
        can_read, _, _ = select.select(rlist, [], [], timeout)

        # read messages from chromecast
        message = data = None
        if self.socket in can_read and not self._force_recon:
            try:
                message = self._read_message()
            except InterruptLoop as exc:
                if self.stop.is_set():
                    self.logger.info(
                        "[%s(%s):%s] Stopped while reading message, disconnecting.",
                        self.fn or "",
                        self.host,
                        self.port,
                    )
                else:
                    self.logger.error(
                        "[%s(%s):%s] Interruption caught without being stopped: %s",
                        self.fn or "",
                        self.host,
                        self.port,
                        exc,
                    )
                return 1
            except ssl.SSLError as exc:
                if exc.errno == ssl.SSL_ERROR_EOF:
                    if self.stop.is_set():
                        return 1
                raise
            except socket.error:
                self._force_recon = True
                self.logger.error(
                    "[%s(%s):%s] Error reading from socket.",
                    self.fn or "",
                    self.host,
                    self.port,
                )
            else:
                data = _dict_from_message_payload(message)

        if self.socketpair[0] in can_read:
            # Clear the socket's buffer
            self.socketpair[0].recv(128)

        # If we are stopped after receiving a message we skip the message
        # and tear down the connection
        if self.stop.is_set():
            return 1

        if not message:
            return 0

        # See if any handlers will accept this message
        self._route_message(message, data)

        if REQUEST_ID in data:
            callback = self._request_callbacks.pop(data[REQUEST_ID], None)
            if callback is not None:
                event = callback["event"]
                callback["response"] = data
                function = callback["function"]
                event.set()
                if function:
                    function(data)

        return 0

    def get_socket(self):
        """
        Returns the socket of the connection to use it in you own
        main loop.
        """
        return self.socket

    def _check_connection(self):
        """
        Checks if the connection is active, and if not reconnect

        :return: True if the connection is active, False if the connection was
                 reset.
        """
        # check if connection is expired
        reset = False
        if self._force_recon:
            self.logger.warning(
                "[%s(%s):%s] Error communicating with socket, resetting connection",
                self.fn or "",
                self.host,
                self.port,
            )
            reset = True

        elif self.heartbeat_controller.is_expired():
            self.logger.warning(
                "[%s(%s):%s] Heartbeat timeout, resetting connection",
                self.fn or "",
                self.host,
                self.port,
            )
            reset = True

        if reset:
            self.receiver_controller.disconnected()
            for channel in self._open_channels:
                self.disconnect_channel(channel)
            self._report_connection_status(
                ConnectionStatus(
                    CONNECTION_STATUS_LOST, NetworkAddress(self.host, self.port)
                )
            )
            try:
                self.initialize_connection()
            except ChromecastConnectionError:
                self.stop.set()
            return False
        return True

    def _route_message(self, message, data: dict):
        """ Route message to any handlers on the message namespace """
        # route message to handlers
        if message.namespace in self._handlers:

            # debug messages
            if message.namespace != NS_HEARTBEAT:
                self.logger.debug(
                    "[%s(%s):%s] Received: %s",
                    self.fn or "",
                    self.host,
                    self.port,
                    _message_to_string(message, data),
                )

            # message handlers
            try:
                handled = self._handlers[message.namespace].receive_message(
                    message, data
                )

                if not handled:
                    if data.get(REQUEST_ID) not in self._request_callbacks:
                        self.logger.debug(
                            "[%s(%s):%s] Message unhandled: %s",
                            self.fn or "",
                            self.host,
                            self.port,
                            _message_to_string(message, data),
                        )
            except Exception:  # pylint: disable=broad-except
                self.logger.exception(
                    (
                        "[%s(%s):%s] Exception caught while sending message to "
                        "controller %s: %s"
                    ),
                    self.fn or "",
                    self.host,
                    self.port,
                    type(self._handlers[message.namespace]).__name__,
                    _message_to_string(message, data),
                )

        else:
            self.logger.debug(
                "[%s(%s):%s] Received unknown namespace: %s",
                self.fn or "",
                self.host,
                self.port,
                _message_to_string(message, data),
            )

    def _cleanup(self):
        """ Cleanup open channels and handlers """
        for channel in self._open_channels:
            try:
                self.disconnect_channel(channel)
            except Exception:  # pylint: disable=broad-except
                pass

        for handler in self._handlers.values():
            try:
                handler.tear_down()
            except Exception:  # pylint: disable=broad-except
                pass

        try:
            self.socket.close()
        except Exception:  # pylint: disable=broad-except
            self.logger.exception(
                "[%s(%s):%s] _cleanup", self.fn or "", self.host, self.port
            )
        self._report_connection_status(
            ConnectionStatus(
                CONNECTION_STATUS_DISCONNECTED, NetworkAddress(self.host, self.port)
            )
        )

        self.socketpair[0].close()
        self.socketpair[1].close()

        self.connecting = True

    def _report_connection_status(self, status):
        """ Report a change in the connection status to any listeners """
        for listener in self._connection_listeners:
            try:
                self.logger.debug(
                    "[%s(%s):%s] connection listener: %x (%s) %s",
                    self.fn or "",
                    self.host,
                    self.port,
                    id(listener),
                    type(listener).__name__,
                    status,
                )
                listener.new_connection_status(status)
            except Exception:  # pylint: disable=broad-except
                self.logger.exception(
                    "[%s(%s):%s] Exception thrown when calling connection listener",
                    self.fn or "",
                    self.host,
                    self.port,
                )

    def _read_bytes_from_socket(self, msglen):
        """ Read bytes from the socket. """
        chunks = []
        bytes_recd = 0
        while bytes_recd < msglen:
            if self.stop.is_set():
                raise InterruptLoop("Stopped while reading from socket")
            try:
                chunk = self.socket.recv(min(msglen - bytes_recd, 2048))
                if chunk == b"":
                    raise socket.error("socket connection broken")
                chunks.append(chunk)
                bytes_recd += len(chunk)
            except socket.timeout:
                self.logger.debug(
                    "[%s(%s):%s] timeout in : _read_bytes_from_socket",
                    self.fn or "",
                    self.host,
                    self.port,
                )
                continue
            except ssl.SSLError as exc:
                # Support older ssl implementations which does not raise
                # socket.timeout on timeouts
                if _is_ssl_timeout(exc):
                    self.logger.debug(
                        "[%s(%s):%s] ssl timeout in : _read_bytes_from_socket",
                        self.fn or "",
                        self.host,
                        self.port,
                    )
                    continue
                raise
        return b"".join(chunks)

    def _read_message(self):
        """ Reads a message from the socket and converts it to a message. """
        # first 4 bytes is Big-Endian payload length
        payload_info = self._read_bytes_from_socket(4)
        read_len = unpack(">I", payload_info)[0]

        # now read the payload
        payload = self._read_bytes_from_socket(read_len)

        # pylint: disable=no-member
        message = cast_channel_pb2.CastMessage()
        message.ParseFromString(payload)

        return message

    # pylint: disable=too-many-arguments
    def send_message(
        self,
        destination_id,
        namespace,
        data,
        inc_session_id=False,
        callback_function=False,
        no_add_request_id=False,
        force=False,
    ):
        """ Send a message to the Chromecast. """

        # namespace is a string containing namespace
        # data is a dict that will be converted to json
        # wait_for_response only works if we have a request id

        # If channel is not open yet, connect to it.
        self._ensure_channel_connected(destination_id)

        request_id = None
        if not no_add_request_id:
            request_id = self._gen_request_id()
            data[REQUEST_ID] = request_id

        if inc_session_id:
            data[SESSION_ID] = self.session_id

        # pylint: disable=no-member
        msg = cast_channel_pb2.CastMessage()

        msg.protocol_version = msg.CASTV2_1_0
        msg.source_id = self.source_id
        msg.destination_id = destination_id
        msg.payload_type = cast_channel_pb2.CastMessage.STRING
        msg.namespace = namespace
        msg.payload_utf8 = _json_to_payload(data)

        # prepend message with Big-Endian 4 byte payload size
        be_size = pack(">I", msg.ByteSize())

        # Log all messages except heartbeat
        if msg.namespace != NS_HEARTBEAT:
            self.logger.debug(
                "[%s(%s):%s] Sending: %s",
                self.fn or "",
                self.host,
                self.port,
                _message_to_string(msg, data),
            )

        if not force and self.stop.is_set():
            raise PyChromecastStopped("Socket client's thread is stopped.")
        if not self.connecting and not self._force_recon:
            try:
                if not no_add_request_id and callback_function:
                    self._request_callbacks[request_id] = {
                        "event": threading.Event(),
                        "response": None,
                        "function": callback_function,
                    }
                self.socket.sendall(be_size + msg.SerializeToString())
            except socket.error:
                self._request_callbacks.pop(request_id, None)
                self._force_recon = True
                self.logger.info(
                    "[%s(%s):%s] Error writing to socket.",
                    self.fn or "",
                    self.host,
                    self.port,
                )
        else:
            raise NotConnected(
                "Chromecast {}:{} is connecting...".format(self.host, self.port)
            )

    def send_platform_message(
        self, namespace, message, inc_session_id=False, callback_function_param=False
    ):
        """ Helper method to send a message to the platform. """
        return self.send_message(
            PLATFORM_DESTINATION_ID,
            namespace,
            message,
            inc_session_id,
            callback_function_param,
        )

    def send_app_message(
        self, namespace, message, inc_session_id=False, callback_function_param=False
    ):
        """ Helper method to send a message to current running app. """
        if namespace not in self.app_namespaces:
            raise UnsupportedNamespace(
                (
                    "Namespace {} is not supported by current app. " "Supported are {}"
                ).format(namespace, ", ".join(self.app_namespaces))
            )

        return self.send_message(
            self.destination_id,
            namespace,
            message,
            inc_session_id,
            callback_function_param,
        )

    def register_connection_listener(self, listener):
        """Register a connection listener for when the socket connection
        changes. Listeners will be called with
        listener.new_connection_status(status)"""
        self._connection_listeners.append(listener)

    def _ensure_channel_connected(self, destination_id):
        """ Ensure we opened a channel to destination_id. """
        if destination_id not in self._open_channels:
            self._open_channels.append(destination_id)

            self.send_message(
                destination_id,
                NS_CONNECTION,
                {
                    MESSAGE_TYPE: TYPE_CONNECT,
                    "origin": {},
                    "userAgent": "PyChromecast",
                    "senderInfo": {
                        "sdkType": 2,
                        "version": "15.605.1.3",
                        "browserVersion": "44.0.2403.30",
                        "platform": 4,
                        "systemVersion": "Macintosh; Intel Mac OS X10_10_3",
                        "connectionType": 1,
                    },
                },
                no_add_request_id=True,
            )

    def disconnect_channel(self, destination_id):
        """ Disconnect a channel with destination_id. """
        if destination_id in self._open_channels:
            try:
                self.send_message(
                    destination_id,
                    NS_CONNECTION,
                    {MESSAGE_TYPE: TYPE_CLOSE, "origin": {}},
                    no_add_request_id=True,
                    force=True,
                )
            except NotConnected:
                pass
            except Exception:  # pylint: disable=broad-except
                self.logger.exception(
                    "[%s(%s):%s] Exception", self.fn or "", self.host, self.port
                )

            self._open_channels.remove(destination_id)

            self.handle_channel_disconnected()

    def handle_channel_disconnected(self):
        """ Handles a channel being disconnected. """
        for namespace in self.app_namespaces:
            if namespace in self._handlers:
                self._handlers[namespace].channel_disconnected()

        self.app_namespaces = []
        self.destination_id = None
        self.session_id = None


class ConnectionController(BaseController):
    """ Controller to respond to connection messages. """

    def __init__(self):
        super(ConnectionController, self).__init__(NS_CONNECTION)

    def receive_message(self, message, data: dict):
        """
        Called when a message is received.

        data is message.payload_utf8 interpreted as a JSON dict.
        """
        if self._socket_client.is_stopped:
            return True

        if data[MESSAGE_TYPE] == TYPE_CLOSE:
            # The cast device is asking us to acknowledge closing this channel.
            self._socket_client.disconnect_channel(message.source_id)

            # Schedule a status update so that a channel is created.
            self._socket_client.receiver_controller.update_status()

            return True

        return False


class HeartbeatController(BaseController):
    """ Controller to respond to heartbeat messages. """

    def __init__(self):
        super(HeartbeatController, self).__init__(NS_HEARTBEAT, target_platform=True)
        self.last_ping = 0
        self.last_pong = time.time()

    def receive_message(self, message, data: dict):
        """
        Called when a heartbeat message is received.

        data is message.payload_utf8 interpreted as a JSON dict.
        """
        if self._socket_client.is_stopped:
            return True

        if data[MESSAGE_TYPE] == TYPE_PING:
            try:
                self._socket_client.send_message(
                    PLATFORM_DESTINATION_ID,
                    self.namespace,
                    {MESSAGE_TYPE: TYPE_PONG},
                    no_add_request_id=True,
                )
            except PyChromecastStopped:
                self._socket_client.logger.debug(
                    "Heartbeat error when sending response, "
                    "Chromecast connection has stopped"
                )

            return True

        if data[MESSAGE_TYPE] == TYPE_PONG:
            self.reset()
            return True

        return False

    def ping(self):
        """ Send a ping message. """
        self.last_ping = time.time()
        try:
            self.send_message({MESSAGE_TYPE: TYPE_PING})
        except NotConnected:
            self._socket_client.logger.error(
                "Chromecast is disconnected. " "Cannot ping until reconnected."
            )

    def reset(self):
        """ Reset expired counter. """
        self.last_pong = time.time()

    def is_expired(self):
        """ Indicates if connection has expired. """
        if time.time() - self.last_ping > HB_PING_TIME:
            self.ping()

        return (time.time() - self.last_pong) > HB_PING_TIME + HB_PONG_TIME


class ReceiverController(BaseController):
    """
    Controller to interact with the Chromecast platform.

    :param cast_type: Type of Chromecast device.
    """

    def __init__(self, cast_type=CAST_TYPE_CHROMECAST):
        super(ReceiverController, self).__init__(NS_RECEIVER, target_platform=True)

        self.status = None
        self.launch_failure = None
        self.app_to_launch = None
        self.cast_type = cast_type
        self.app_launch_event = threading.Event()
        self.app_launch_event_function = None

        self._status_listeners = []
        self._launch_error_listeners = []

    def disconnected(self):
        """ Called when disconnected. Will erase status. """
        self.logger.info("Receiver:channel_disconnected")
        self.status = None

    @property
    def app_id(self):
        """ Convenience method to retrieve current app id. """
        return self.status.app_id if self.status else None

    def receive_message(self, message, data: dict):
        """
        Called when a receiver message is received.

        data is message.payload_utf8 interpreted as a JSON dict.
        """
        if data[MESSAGE_TYPE] == TYPE_RECEIVER_STATUS:
            self._process_get_status(data)

            return True

        if data[MESSAGE_TYPE] == TYPE_LAUNCH_ERROR:
            self._process_launch_error(data)

            return True

        return False

    def register_status_listener(self, listener):
        """Register a status listener for when a new Chromecast status
        has been received. Listeners will be called with
        listener.new_cast_status(status)"""
        self._status_listeners.append(listener)

    def register_launch_error_listener(self, listener):
        """Register a listener for when a new launch error message
        has been received. Listeners will be called with
        listener.new_launch_error(launch_failure)"""
        self._launch_error_listeners.append(listener)

    def update_status(self, callback_function_param=False):
        """ Sends a message to the Chromecast to update the status. """
        self.logger.debug("Receiver:Updating status")
        self.send_message(
            {MESSAGE_TYPE: TYPE_GET_STATUS}, callback_function=callback_function_param
        )

    def launch_app(self, app_id, force_launch=False, callback_function=False):
        """Launches an app on the Chromecast.

        Will only launch if it is not currently running unless
        force_launch=True."""

        if not force_launch and self.status is None:
            self.update_status(
                lambda response: self._send_launch_message(
                    app_id, force_launch, callback_function
                )
            )
        else:
            self._send_launch_message(app_id, force_launch, callback_function)

    def _send_launch_message(self, app_id, force_launch=False, callback_function=False):
        if force_launch or self.app_id != app_id:
            self.logger.info("Receiver:Launching app %s", app_id)

            self.app_to_launch = app_id
            self.app_launch_event.clear()
            self.app_launch_event_function = callback_function
            self.launch_failure = None

            self.send_message({MESSAGE_TYPE: TYPE_LAUNCH, APP_ID: app_id})
        else:
            self.logger.info("Not launching app %s - already running", app_id)
            if callback_function:
                callback_function()

    def stop_app(self, callback_function_param=False):
        """ Stops the current running app on the Chromecast. """
        self.logger.info("Receiver:Stopping current app '%s'", self.app_id)
        return self.send_message(
            {MESSAGE_TYPE: "STOP"},
            inc_session_id=True,
            callback_function=callback_function_param,
        )

    def set_volume(self, volume):
        """Allows to set volume. Should be value between 0..1.
        Returns the new volume.

        """
        volume = min(max(0, volume), 1)
        self.logger.info("Receiver:setting volume to %.1f", volume)
        self.send_message({MESSAGE_TYPE: "SET_VOLUME", "volume": {"level": volume}})
        return volume

    def set_volume_muted(self, muted):
        """ Allows to mute volume. """
        self.send_message({MESSAGE_TYPE: "SET_VOLUME", "volume": {"muted": muted}})

    @staticmethod
    def _parse_status(data, cast_type):
        """
        Parses a STATUS message and returns a CastStatus object.

        :type data: dict
        :param cast_type: Type of Chromecast.
        :rtype: CastStatus
        """
        data = data.get("status", {})

        volume_data = data.get("volume", {})

        try:
            app_data = data["applications"][0]
        except (KeyError, IndexError):
            app_data = {}

        is_audio = cast_type in (CAST_TYPE_AUDIO, CAST_TYPE_GROUP)

        status = CastStatus(
            data.get("isActiveInput", None if is_audio else False),
            data.get("isStandBy", None if is_audio else True),
            volume_data.get("level", 1.0),
            volume_data.get("muted", False),
            app_data.get(APP_ID),
            app_data.get("displayName"),
            [item["name"] for item in app_data.get("namespaces", [])],
            app_data.get(SESSION_ID),
            app_data.get("transportId"),
            app_data.get("statusText", ""),
            app_data.get("iconUrl"),
        )
        return status

    def _process_get_status(self, data):
        """ Processes a received STATUS message and notifies listeners. """
        status = self._parse_status(data, self.cast_type)
        is_new_app = self.app_id != status.app_id and self.app_to_launch
        self.status = status

        self.logger.debug("Received status: %s", self.status)
        self._report_status()

        if is_new_app and self.app_to_launch == self.app_id:
            self.app_to_launch = None
            self.app_launch_event.set()
            if self.app_launch_event_function:
                self.logger.debug("Start app_launch_event_function...")
                self.app_launch_event_function()
                self.app_launch_event_function = None

    def _report_status(self):
        """ Reports the current status to all listeners. """
        for listener in self._status_listeners:
            try:
                listener.new_cast_status(self.status)
            except Exception:  # pylint: disable=broad-except
                self.logger.exception(
                    "Exception thrown when calling cast status listener"
                )

    @staticmethod
    def _parse_launch_error(data):
        """
        Parses a LAUNCH_ERROR message and returns a LaunchFailure object.

        :type data: dict
        :rtype: LaunchFailure
        """
        return LaunchFailure(
            data.get(ERROR_REASON, None), data.get(APP_ID), data.get(REQUEST_ID)
        )

    def _process_launch_error(self, data):
        """
        Processes a received LAUNCH_ERROR message and notifies listeners.
        """
        launch_failure = self._parse_launch_error(data)
        self.launch_failure = launch_failure

        if self.app_to_launch:
            self.app_to_launch = None
            self.app_launch_event.set()

        self.logger.debug("Launch status: %s", launch_failure)

        for listener in self._launch_error_listeners:
            try:
                listener.new_launch_error(launch_failure)
            except Exception:  # pylint: disable=broad-except
                self.logger.exception(
                    "Exception thrown when calling launch error listener"
                )

    def tear_down(self):
        """ Called when controller is destroyed. """
        super(ReceiverController, self).tear_down()

        self.status = None
        self.launch_failure = None
        self.app_to_launch = None
        self.app_launch_event.clear()

        self._status_listeners[:] = []


def new_socket():
    """
    Create a new socket with OS-specific parameters

    Try to set SO_REUSEPORT for BSD-flavored systems if it's an option.
    Catches errors if not.
    """
    new_sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    new_sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

    try:
        # noinspection PyUnresolvedReferences
        reuseport = socket.SO_REUSEPORT
    except AttributeError:
        pass
    else:
        try:
            new_sock.setsockopt(socket.SOL_SOCKET, reuseport, 1)
        except (OSError, socket.error) as err:
            # OSError on python 3, socket.error on python 2
            if err.errno != errno.ENOPROTOOPT:
                raise

    return new_sock
