text: """
  The MIT License (MIT)
  
  Copyright (c) 2015-2021 Rapptz
  Copyright (c) 2021-present Disnake Development
  
  Permission is hereby granted, free of charge, to any person obtaining a
  copy of this software and associated documentation files (the "Software"),
  to deal in the Software without restriction, including without limitation
  the rights to use, copy, modify, merge, publish, distribute, sublicense,
  and/or sell copies of the Software, and to permit persons to whom the
  Software is furnished to do so, subject to the following conditions:
  
  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.
  
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  DEALINGS IN THE SOFTWARE.
  
  
  Some documentation to refer to:
  
  - Our main web socket (mWS) sends opcode 4 with a guild ID and channel ID.
  - The mWS receives VOICE_STATE_UPDATE and VOICE_SERVER_UPDATE.
  - We pull the session_id from VOICE_STATE_UPDATE.
  - We pull the token, endpoint and server_id from VOICE_SERVER_UPDATE.
  - Then we initiate the voice web socket (vWS) pointing to the endpoint.
  - We send opcode 0 with the user_id, server_id, session_id and token using the vWS.
  - The vWS sends back opcode 2 with an ssrc, port, modes(array) and hearbeat_interval.
  - We send a UDP discovery packet to endpoint:port and receive our IP and our port in LE.
  - Then we send our IP and port via vWS with opcode 1.
  - When that's all done, we receive opcode 4 from the vWS.
  - Finally we can transmit data to endpoint:port.
  """
  
  from __future__ import annotations
  
  import asyncio
  import logging
  import socket
  import struct
  import threading
  from typing import TYPE_CHECKING, Any, Callable, List, Optional, Tuple
  
  from . import opus, utils
  from .backoff import ExponentialBackoff
  from .errors import ClientException, ConnectionClosed
  from .gateway import *
  from .player import AudioPlayer, AudioSource
  from .utils import MISSING
  
  if TYPE_CHECKING:
      from . import abc
      from .client import Client
      from .guild import Guild
      from .opus import Encoder
      from .state import ConnectionState
      from .types.voice import (
          GuildVoiceState as GuildVoiceStatePayload,
          SupportedModes,
          VoiceServerUpdate as VoiceServerUpdatePayload,
      )
      from .user import ClientUser
  
  
  has_nacl: bool
  
  try:
      import nacl.secret  # type: ignore
  
      has_nacl = True
  except ImportError:
      has_nacl = False
  
  __all__ = (
      "VoiceProtocol",
      "VoiceClient",
  )
  
  
  _log = logging.getLogger(__name__)
  
  
  class VoiceProtocol:
      """A class that represents the Discord voice protocol.
  
      This is an abstract class. The library provides a concrete implementation
      under :class:`VoiceClient`.
  
      This class allows you to implement a protocol to allow for an external
      method of sending voice, such as Lavalink_ or a native library implementation.
  
      These classes are passed to :meth:`abc.Connectable.connect <VoiceChannel.connect>`.
  
      .. _Lavalink: https://github.com/freyacodes/Lavalink
  
      Parameters
      ------------
      client: :class:`Client`
          The client (or its subclasses) that started the connection request.
      channel: :class:`abc.Connectable`
          The voice channel that is being connected to.
      """
  
      def __init__(self, client: Client, channel: abc.Connectable) -> None:
          self.client: Client = client
          self.channel: abc.Connectable = channel
  
      async def on_voice_state_update(self, data: GuildVoiceStatePayload) -> None:
          """|coro|
  
          An abstract method that is called when the client's voice state
          has changed. This corresponds to ``VOICE_STATE_UPDATE``.
  
          Parameters
          ------------
          data: :class:`dict`
              The raw `voice state payload`__.
  
              .. _voice_state_update_payload: https://discord.com/developers/docs/resources/voice#voice-state-object
  
              __ voice_state_update_payload_
          """
          raise NotImplementedError
  
      async def on_voice_server_update(self, data: VoiceServerUpdatePayload) -> None:
          """|coro|
  
          An abstract method that is called when initially connecting to voice.
          This corresponds to ``VOICE_SERVER_UPDATE``.
  
          Parameters
          ------------
          data: :class:`dict`
              The raw `voice server update payload`__.
  
              .. _voice_server_update_payload: https://discord.com/developers/docs/topics/gateway#voice-server-update-voice-server-update-event-fields
  
              __ voice_server_update_payload_
          """
          raise NotImplementedError
  
      async def connect(self, *, timeout: float, reconnect: bool) -> None:
          """|coro|
  
          An abstract method called when the client initiates the connection request.
  
          When a connection is requested initially, the library calls the constructor
          under ``__init__`` and then calls :meth:`connect`. If :meth:`connect` fails at
          some point then :meth:`disconnect` is called.
  
          Within this method, to start the voice connection flow it is recommended to
          use :meth:`Guild.change_voice_state` to start the flow. After which,
          :meth:`on_voice_server_update` and :meth:`on_voice_state_update` will be called.
          The order that these two are called is unspecified.
  
          Parameters
          ------------
          timeout: :class:`float`
              The timeout for the connection.
          reconnect: :class:`bool`
              Whether reconnection is expected.
          """
          raise NotImplementedError
  
      async def disconnect(self, *, force: bool) -> None:
          """|coro|
  
          An abstract method called when the client terminates the connection.
  
          See :meth:`cleanup`.
  
          Parameters
          ------------
          force: :class:`bool`
              Whether the disconnection was forced.
          """
          raise NotImplementedError
  
      def cleanup(self) -> None:
          """This method *must* be called to ensure proper clean-up during a disconnect.
  
          It is advisable to call this from within :meth:`disconnect` when you are
          completely done with the voice protocol instance.
  
          This method removes it from the internal state cache that keeps track of
          currently alive voice clients. Failure to clean-up will cause subsequent
          connections to report that it's still connected.
          """
          key_id, _ = self.channel._get_voice_client_key()
          self.client._connection._remove_voice_client(key_id)
  
  
  class VoiceClient(VoiceProtocol):
      """Represents a Discord voice connection.
  
      You do not create these, you typically get them from
      e.g. :meth:`VoiceChannel.connect`.
  
      Warning
      --------
      In order to use PCM based AudioSources, you must have the opus library
      installed on your system and loaded through :func:`opus.load_opus`.
      Otherwise, your AudioSources must be opus encoded (e.g. using :class:`FFmpegOpusAudio`)
      or the library will not be able to transmit audio.
  
      Attributes
      -----------
      session_id: :class:`str`
          The voice connection session ID.
      token: :class:`str`
          The voice connection token.
      endpoint: :class:`str`
          The endpoint we are connecting to.
      channel: :class:`abc.Connectable`
          The voice channel connected to.
      loop: :class:`asyncio.AbstractEventLoop`
          The event loop that the voice client is running on.
      """
  
      endpoint_ip: str
      voice_port: int
      secret_key: List[int]
      ssrc: int
  
      def __init__(self, client: Client, channel: abc.Connectable):
          if not has_nacl:
              raise RuntimeError("PyNaCl library needed in order to use voice")
  
          super().__init__(client, channel)
          state = client._connection
          self.token: str = MISSING
          self.socket = MISSING
          self.loop: asyncio.AbstractEventLoop = state.loop
          self._state: ConnectionState = state
          # this will be used in the AudioPlayer thread
          self._connected: threading.Event = threading.Event()
  
          self._handshaking: bool = False
          self._potentially_reconnecting: bool = False
          self._voice_state_complete: asyncio.Event = asyncio.Event()
          self._voice_server_complete: asyncio.Event = asyncio.Event()
  
          self.mode: str = MISSING
          self._connections: int = 0
          self.sequence: int = 0
          self.timestamp: int = 0
          self.timeout: float = 0
          self._runner: asyncio.Task = MISSING
          self._player: Optional[AudioPlayer] = None
          self.encoder: Encoder = MISSING
          self._lite_nonce: int = 0
          self.ws: DiscordVoiceWebSocket = MISSING
  
      warn_nacl = not has_nacl
      supported_modes: Tuple[SupportedModes, ...] = (
          "xsalsa20_poly1305_lite",
          "xsalsa20_poly1305_suffix",
          "xsalsa20_poly1305",
      )
  
      @property
      def guild(self) -> Optional[Guild]:
          """Optional[:class:`Guild`]: The guild we're connected to, if applicable."""
          return getattr(self.channel, "guild", None)
  
      @property
      def user(self) -> ClientUser:
          """:class:`ClientUser`: The user connected to voice (i.e. ourselves)."""
          return self._state.user
  
      def checked_add(self, attr, value, limit):
          val = getattr(self, attr)
          if val + value > limit:
              setattr(self, attr, 0)
          else:
              setattr(self, attr, val + value)
  
      # connection related
  
      async def on_voice_state_update(self, data: GuildVoiceStatePayload) -> None:
          self.session_id = data["session_id"]
          channel_id = data["channel_id"]
  
          if not self._handshaking or self._potentially_reconnecting:
              # If we're done handshaking then we just need to update ourselves
              # If we're potentially reconnecting due to a 4014, then we need to differentiate
              # a channel move and an actual force disconnect
              if channel_id is None:
                  # We're being disconnected so cleanup
                  await self.disconnect()
              else:
                  guild = self.guild
                  self.channel = channel_id and guild and guild.get_channel(int(channel_id))  # type: ignore
          else:
              self._voice_state_complete.set()
  
      async def on_voice_server_update(self, data: VoiceServerUpdatePayload) -> None:
          if self._voice_server_complete.is_set():
              _log.info("Ignoring extraneous voice server update.")
              return
  
          self.token = data.get("token")
          self.server_id = int(data["guild_id"])
          endpoint = data.get("endpoint")
  
          if endpoint is None or self.token is None:
              _log.warning(
                  "Awaiting endpoint... This requires waiting. "
                  "If timeout occurred considering raising the timeout and reconnecting."
              )
              return
  
          self.endpoint, _, _ = endpoint.rpartition(":")
          if self.endpoint.startswith("wss://"):
              # Just in case, strip it off since we're going to add it later
              self.endpoint = self.endpoint[6:]
  
          # This gets set later
          self.endpoint_ip = MISSING
  
          self.socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
          self.socket.setblocking(False)
  
          if not self._handshaking:
              # If we're not handshaking then we need to terminate our previous connection in the websocket
              await self.ws.close(4000)
              return
  
          self._voice_server_complete.set()
  
      async def voice_connect(self) -> None:
          await self.channel.guild.change_voice_state(channel=self.channel)
  
      async def voice_disconnect(self) -> None:
          _log.info(
              "The voice handshake is being terminated for Channel ID %s (Guild ID %s)",
              self.channel.id,
              self.guild.id,
          )
          await self.channel.guild.change_voice_state(channel=None)
  
      def prepare_handshake(self) -> None:
          self._voice_state_complete.clear()
          self._voice_server_complete.clear()
          self._handshaking = True
          _log.info("Starting voice handshake... (connection attempt %d)", self._connections + 1)
          self._connections += 1
  
      def finish_handshake(self) -> None:
          _log.info("Voice handshake complete. Endpoint found %s", self.endpoint)
          self._handshaking = False
          self._voice_server_complete.clear()
          self._voice_state_complete.clear()
  
      async def connect_websocket(self) -> DiscordVoiceWebSocket:
          ws = await DiscordVoiceWebSocket.from_client(self)
          self._connected.clear()
          while ws.secret_key is None:
              await ws.poll_event()
          self._connected.set()
          return ws
  
      async def connect(self, *, reconnect: bool, timeout: float) -> None:
          _log.info("Connecting to voice...")
          self.timeout = timeout
  
          for i in range(5):
              self.prepare_handshake()
  
              # This has to be created before we start the flow.
              futures = [
                  self._voice_state_complete.wait(),
                  self._voice_server_complete.wait(),
              ]
  
              # Start the connection flow
              await self.voice_connect()
  
              try:
                  await utils.sane_wait_for(futures, timeout=timeout)
              except asyncio.TimeoutError:
                  await self.disconnect(force=True)
                  raise
  
              self.finish_handshake()
  
              try:
                  self.ws = await self.connect_websocket()
                  break
              except (ConnectionClosed, asyncio.TimeoutError):
                  if reconnect:
                      _log.exception("Failed to connect to voice... Retrying...")
                      await asyncio.sleep(1 + i * 2.0)
                      await self.voice_disconnect()
                      continue
                  else:
                      raise
  
          if self._runner is MISSING:
              self._runner = self.loop.create_task(self.poll_voice_ws(reconnect))
  
      async def potential_reconnect(self) -> bool:
          # Attempt to stop the player thread from playing early
          self._connected.clear()
          self.prepare_handshake()
          self._potentially_reconnecting = True
          try:
              # We only care about VOICE_SERVER_UPDATE since VOICE_STATE_UPDATE can come before we get disconnected
              await asyncio.wait_for(self._voice_server_complete.wait(), timeout=self.timeout)
          except asyncio.TimeoutError:
              self._potentially_reconnecting = False
              await self.disconnect(force=True)
              return False
  
          self.finish_handshake()
          self._potentially_reconnecting = False
          try:
              self.ws = await self.connect_websocket()
          except (ConnectionClosed, asyncio.TimeoutError):
              return False
          else:
              return True
  
      @property
      def latency(self) -> float:
          """:class:`float`: Latency between a HEARTBEAT and a HEARTBEAT_ACK in seconds.
  
          This could be referred to as the Discord Voice WebSocket latency and is
          an analogue of user's voice latencies as seen in the Discord client.
  
          .. versionadded:: 1.4
          """
          ws = self.ws
          return float("inf") if not ws else ws.latency
  
      @property
      def average_latency(self) -> float:
          """:class:`float`: Average of most recent 20 HEARTBEAT latencies in seconds.
  
          .. versionadded:: 1.4
          """
          ws = self.ws
          return float("inf") if not ws else ws.average_latency
  
      async def poll_voice_ws(self, reconnect: bool) -> None:
          backoff = ExponentialBackoff()
          while True:
              try:
                  await self.ws.poll_event()
              except (ConnectionClosed, asyncio.TimeoutError) as exc:
                  if isinstance(exc, ConnectionClosed):
                      # The following close codes are undocumented so I will document them here.
                      # 1000 - normal closure (obviously)
                      # 4014 - voice channel has been deleted.
                      # 4015 - voice server has crashed
                      if exc.code in (1000, 4015):
                          _log.info("Disconnecting from voice normally, close code %d.", exc.code)
                          await self.disconnect()
                          break
                      if exc.code == 4014:
                          _log.info("Disconnected from voice by force... potentially reconnecting.")
                          successful = await self.potential_reconnect()
                          if not successful:
                              _log.info(
                                  "Reconnect was unsuccessful, disconnecting from voice normally..."
                              )
                              await self.disconnect()
                              break
                          else:
                              continue
  
                  if not reconnect:
                      await self.disconnect()
                      raise
  
                  retry = backoff.delay()
                  _log.exception("Disconnected from voice... Reconnecting in %.2fs.", retry)
                  self._connected.clear()
                  await asyncio.sleep(retry)
                  await self.voice_disconnect()
                  try:
                      await self.connect(reconnect=True, timeout=self.timeout)
                  except asyncio.TimeoutError:
                      # at this point we've retried 5 times... let's continue the loop.
                      _log.warning("Could not connect to voice... Retrying...")
                      continue
  
      async def disconnect(self, *, force: bool = False) -> None:
          """|coro|
  
          Disconnects this voice client from voice.
          """
          if not force and not self.is_connected():
              return
  
          self.stop()
          self._connected.clear()
  
          try:
              if self.ws:
                  await self.ws.close()
  
              await self.voice_disconnect()
          finally:
              self.cleanup()
              if self.socket:
                  self.socket.close()
  
      async def move_to(self, channel: abc.Snowflake) -> None:
          """|coro|
  
          Moves you to a different voice channel.
  
          Parameters
          -----------
          channel: :class:`abc.Snowflake`
              The channel to move to. Must be a voice channel.
          """
          await self.channel.guild.change_voice_state(channel=channel)
  
      def is_connected(self) -> bool:
          """Indicates if the voice client is connected to voice."""
          return self._connected.is_set()
  
      # audio related
  
      def _get_voice_packet(self, data):
          header = bytearray(12)
  
          # Formulate rtp header
          header[0] = 0x80
          header[1] = 0x78
          struct.pack_into(">H", header, 2, self.sequence)
          struct.pack_into(">I", header, 4, self.timestamp)
          struct.pack_into(">I", header, 8, self.ssrc)
  
          encrypt_packet = getattr(self, "_encrypt_" + self.mode)
          return encrypt_packet(header, data)
  
      def _encrypt_xsalsa20_poly1305(self, header: bytes, data) -> bytes:
          box = nacl.secret.SecretBox(bytes(self.secret_key))
          nonce = bytearray(24)
          nonce[:12] = header
  
          return header + box.encrypt(bytes(data), bytes(nonce)).ciphertext
  
      def _encrypt_xsalsa20_poly1305_suffix(self, header: bytes, data) -> bytes:
          box = nacl.secret.SecretBox(bytes(self.secret_key))
          nonce = nacl.utils.random(nacl.secret.SecretBox.NONCE_SIZE)
  
          return header + box.encrypt(bytes(data), nonce).ciphertext + nonce
  
      def _encrypt_xsalsa20_poly1305_lite(self, header: bytes, data) -> bytes:
          box = nacl.secret.SecretBox(bytes(self.secret_key))
          nonce = bytearray(24)
  
          nonce[:4] = struct.pack(">I", self._lite_nonce)
          self.checked_add("_lite_nonce", 1, 4294967295)
  
          return header + box.encrypt(bytes(data), bytes(nonce)).ciphertext + nonce[:4]
  
      def play(
          self, source: AudioSource, *, after: Callable[[Optional[Exception]], Any] = None
      ) -> None:
          """Plays an :class:`AudioSource`.
  
          The finalizer, ``after`` is called after the source has been exhausted
          or an error occurred.
  
          If an error happens while the audio player is running, the exception is
          caught and the audio player is then stopped.  If no after callback is
          passed, any caught exception will be displayed as if it were raised.
  
          Parameters
          -----------
          source: :class:`AudioSource`
              The audio source we're reading from.
          after: Callable[[Optional[:class:`Exception`]], Any]
              The finalizer that is called after the stream is exhausted.
              This function must have a single parameter, ``error``, that
              denotes an optional exception that was raised during playing.
  
          Raises
          -------
          ClientException
              Already playing audio or not connected.
          TypeError
              Source is not a :class:`AudioSource` or after is not a callable.
          OpusNotLoaded
              Source is not opus encoded and opus is not loaded.
          """
  
          if not self.is_connected():
              raise ClientException("Not connected to voice.")
  
          if self.is_playing():
              raise ClientException("Already playing audio.")
  
          if not isinstance(source, AudioSource):
              raise TypeError(f"source must be an AudioSource not {source.__class__.__name__}")
  
          if not self.encoder and not source.is_opus():
              self.encoder = opus.Encoder()
  
          self._player = AudioPlayer(source, self, after=after)
          self._player.start()
  
      def is_playing(self) -> bool:
          """Indicates if we're currently playing audio."""
          return self._player is not None and self._player.is_playing()
  
      def is_paused(self) -> bool:
          """Indicates if we're playing audio, but if we're paused."""
          return self._player is not None and self._player.is_paused()
  
      def stop(self) -> None:
          """Stops playing audio."""
          if self._player:
              self._player.stop()
              self._player = None
  
      def pause(self) -> None:
          """Pauses the audio playing."""
          if self._player:
              self._player.pause()
  
      def resume(self) -> None:
          """Resumes the audio playing."""
          if self._player:
              self._player.resume()
  
      @property
      def source(self) -> Optional[AudioSource]:
          """Optional[:class:`AudioSource`]: The audio source being played, if playing.
  
          This property can also be used to change the audio source currently being played.
          """
          return self._player.source if self._player else None
  
      @source.setter
      def source(self, value: AudioSource) -> None:
          if not isinstance(value, AudioSource):
              raise TypeError(f"expected AudioSource not {value.__class__.__name__}.")
  
          if self._player is None:
              raise ValueError("Not playing anything.")
  
          self._player._set_source(value)
  
      def send_audio_packet(self, data: bytes, *, encode: bool = True) -> None:
          """Sends an audio packet composed of the data.
  
          You must be connected to play audio.
  
          Parameters
          ----------
          data: :class:`bytes`
              The :term:`py:bytes-like object` denoting PCM or Opus voice data.
          encode: :class:`bool`
              Indicates if ``data`` should be encoded into Opus.
  
          Raises
          -------
          ClientException
              You are not connected.
          opus.OpusError
              Encoding the data failed.
          """
  
          self.checked_add("sequence", 1, 65535)
          if encode:
              encoded_data = self.encoder.encode(data, self.encoder.SAMPLES_PER_FRAME)
          else:
              encoded_data = data
          packet = self._get_voice_packet(encoded_data)
          try:
              self.socket.sendto(packet, (self.endpoint_ip, self.voice_port))
          except BlockingIOError:
              _log.warning(
                  "A packet has been dropped (seq: %s, timestamp: %s)", self.sequence, self.timestamp
              )
  
          self.checked_add("timestamp", opus.Encoder.SAMPLES_PER_FRAME, 4294967295)
  