core/homeassistant/components/cast/helpers.py

"""Helpers to deal with Cast devices."""

from __future__ import annotations

import configparser
from dataclasses import dataclass
import logging
from typing import TYPE_CHECKING
from urllib.parse import urlparse

import aiohttp
import attr
import pychromecast
from pychromecast import dial
from pychromecast.const import CAST_TYPE_GROUP
from pychromecast.models import CastInfo

from homeassistant.core import HomeAssistant
from homeassistant.helpers import aiohttp_client

from .const import DOMAIN

if TYPE_CHECKING:
    from homeassistant.components import zeroconf


_LOGGER = logging.getLogger(__name__)

_PLS_SECTION_PLAYLIST = "playlist"


@attr.s(slots=True, frozen=True)
class ChromecastInfo:
    """Class to hold all data about a chromecast for creating connections.

    This also has the same attributes as the mDNS fields by zeroconf.
    """

    cast_info: CastInfo = attr.ib()
    is_dynamic_group = attr.ib(type=bool | None, default=None)

    @property
    def friendly_name(self) -> str:
        """Return the Friendly Name."""
        return self.cast_info.friendly_name

    @property
    def is_audio_group(self) -> bool:
        """Return if the cast is an audio group."""
        return self.cast_info.cast_type == CAST_TYPE_GROUP

    @property
    def uuid(self) -> bool:
        """Return the UUID."""
        return self.cast_info.uuid

    def fill_out_missing_chromecast_info(self, hass: HomeAssistant) -> ChromecastInfo:
        """Return a new ChromecastInfo object with missing attributes filled in.

        Uses blocking HTTP / HTTPS.
        """
        cast_info = self.cast_info
        if self.cast_info.cast_type is None or self.cast_info.manufacturer is None:
            unknown_models = hass.data[DOMAIN]["unknown_models"]
            if self.cast_info.model_name not in unknown_models:
                # Manufacturer and cast type is not available in mDNS data,
                # get it over HTTP
                cast_info = dial.get_cast_type(
                    cast_info,
                    zconf=ChromeCastZeroconf.get_zeroconf(),
                )
                unknown_models[self.cast_info.model_name] = (
                    cast_info.cast_type,
                    cast_info.manufacturer,
                )

                report_issue = (
                    "create a bug report at "
                    "https://github.com/home-assistant/core/issues?q=is%3Aopen+is%3Aissue"
                    "+label%3A%22integration%3A+cast%22"
                )

                _LOGGER.debug(
                    (
                        "Fetched cast details for unknown model '%s' manufacturer:"
                        " '%s', type: '%s'. Please %s"
                    ),
                    cast_info.model_name,
                    cast_info.manufacturer,
                    cast_info.cast_type,
                    report_issue,
                )
            else:
                cast_type, manufacturer = unknown_models[self.cast_info.model_name]
                cast_info = CastInfo(
                    cast_info.services,
                    cast_info.uuid,
                    cast_info.model_name,
                    cast_info.friendly_name,
                    cast_info.host,
                    cast_info.port,
                    cast_type,
                    manufacturer,
                )

        if not self.is_audio_group or self.is_dynamic_group is not None:
            # We have all information, no need to check HTTP API.
            return ChromecastInfo(cast_info=cast_info)

        # Fill out missing group information via HTTP API.
        is_dynamic_group = False
        http_group_status = None
        http_group_status = dial.get_multizone_status(
            None,
            services=self.cast_info.services,
            zconf=ChromeCastZeroconf.get_zeroconf(),
        )
        if http_group_status is not None:
            is_dynamic_group = any(
                g.uuid == self.cast_info.uuid for g in http_group_status.dynamic_groups
            )

        return ChromecastInfo(
            cast_info=cast_info,
            is_dynamic_group=is_dynamic_group,
        )


class ChromeCastZeroconf:
    """Class to hold a zeroconf instance."""

    __zconf: zeroconf.HaZeroconf | None = None

    @classmethod
    def set_zeroconf(cls, zconf: zeroconf.HaZeroconf) -> None:
        """Set zeroconf."""
        cls.__zconf = zconf

    @classmethod
    def get_zeroconf(cls) -> zeroconf.HaZeroconf | None:
        """Get zeroconf."""
        return cls.__zconf


class CastStatusListener(
    pychromecast.controllers.media.MediaStatusListener,
    pychromecast.controllers.multizone.MultiZoneManagerListener,
    pychromecast.controllers.receiver.CastStatusListener,
    pychromecast.socket_client.ConnectionStatusListener,
):
    """Helper class to handle pychromecast status callbacks.

    Necessary because a CastDevice entity or dynamic group can create a new
    socket client and therefore callbacks from multiple chromecast connections can
    potentially arrive. This class allows invalidating past chromecast objects.
    """

    def __init__(self, cast_device, chromecast, mz_mgr, mz_only=False):
        """Initialize the status listener."""
        self._cast_device = cast_device
        self._uuid = chromecast.uuid
        self._valid = True
        self._mz_mgr = mz_mgr

        if cast_device._cast_info.is_audio_group:  # noqa: SLF001
            self._mz_mgr.add_multizone(chromecast)
        if mz_only:
            return

        chromecast.register_status_listener(self)
        chromecast.socket_client.media_controller.register_status_listener(self)
        chromecast.register_connection_listener(self)
        if not cast_device._cast_info.is_audio_group:  # noqa: SLF001
            self._mz_mgr.register_listener(chromecast.uuid, self)

    def new_cast_status(self, status):
        """Handle reception of a new CastStatus."""
        if self._valid:
            self._cast_device.new_cast_status(status)

    def new_media_status(self, status):
        """Handle reception of a new MediaStatus."""
        if self._valid:
            self._cast_device.new_media_status(status)

    def load_media_failed(self, queue_item_id, error_code):
        """Handle reception of a new MediaStatus."""
        if self._valid:
            self._cast_device.load_media_failed(queue_item_id, error_code)

    def new_connection_status(self, status):
        """Handle reception of a new ConnectionStatus."""
        if self._valid:
            self._cast_device.new_connection_status(status)

    def added_to_multizone(self, group_uuid):
        """Handle the cast added to a group."""

    def removed_from_multizone(self, group_uuid):
        """Handle the cast removed from a group."""
        if self._valid:
            self._cast_device.multizone_new_media_status(group_uuid, None)

    def multizone_new_cast_status(self, group_uuid, cast_status):
        """Handle reception of a new CastStatus for a group."""

    def multizone_new_media_status(self, group_uuid, media_status):
        """Handle reception of a new MediaStatus for a group."""
        if self._valid:
            self._cast_device.multizone_new_media_status(group_uuid, media_status)

    def invalidate(self):
        """Invalidate this status listener.

        All following callbacks won't be forwarded.
        """
        if self._cast_device._cast_info.is_audio_group:  # noqa: SLF001
            self._mz_mgr.remove_multizone(self._uuid)
        else:
            self._mz_mgr.deregister_listener(self._uuid, self)
        self._valid = False


class PlaylistError(Exception):
    """Exception wrapper for pls and m3u helpers."""


class PlaylistSupported(PlaylistError):
    """The playlist is supported by cast devices and should not be parsed."""


@dataclass
class PlaylistItem:
    """Playlist item."""

    length: str | None
    title: str | None
    url: str


def _is_url(url):
    """Validate the URL can be parsed and at least has scheme + netloc."""
    result = urlparse(url)
    return all([result.scheme, result.netloc])


async def _fetch_playlist(hass, url, supported_content_types):
    """Fetch a playlist from the given url."""
    try:
        session = aiohttp_client.async_get_clientsession(hass, verify_ssl=False)
        async with session.get(url, timeout=aiohttp.ClientTimeout(total=5)) as resp:
            charset = resp.charset or "utf-8"
            if resp.content_type in supported_content_types:
                raise PlaylistSupported
            try:
                playlist_data = (await resp.content.read(64 * 1024)).decode(charset)
            except ValueError as err:
                raise PlaylistError(f"Could not decode playlist {url}") from err
    except TimeoutError as err:
        raise PlaylistError(f"Timeout while fetching playlist {url}") from err
    except aiohttp.client_exceptions.ClientError as err:
        raise PlaylistError(f"Error while fetching playlist {url}") from err

    return playlist_data


async def parse_m3u(hass, url):
    """Very simple m3u parser.

    Based on https://github.com/dvndrsn/M3uParser/blob/master/m3uparser.py
    """
    # From Mozilla gecko source: https://github.com/mozilla/gecko-dev/blob/c4c1adbae87bf2d128c39832d72498550ee1b4b8/dom/media/DecoderTraits.cpp#L47-L52
    hls_content_types = (
        # https://tools.ietf.org/html/draft-pantos-http-live-streaming-19#section-10
        "application/vnd.apple.mpegurl",
        # Additional informal types used by Mozilla gecko not included as they
        # don't reliably indicate HLS streams
    )
    m3u_data = await _fetch_playlist(hass, url, hls_content_types)
    m3u_lines = m3u_data.splitlines()

    playlist = []

    length = None
    title = None

    for line in m3u_lines:
        line = line.strip()
        if line.startswith("#EXTINF:"):
            # Get length and title from #EXTINF line
            info = line.split("#EXTINF:")[1].split(",", 1)
            if len(info) != 2:
                _LOGGER.warning("Ignoring invalid extinf %s in playlist %s", line, url)
                continue
            length = info[0].split(" ", 1)
            title = info[1].strip()
        elif line.startswith(("#EXT-X-VERSION:", "#EXT-X-STREAM-INF:")):
            # HLS stream, supported by cast devices
            raise PlaylistSupported("HLS")
        elif line.startswith("#"):
            # Ignore other extensions
            continue
        elif len(line) != 0:
            # Get song path from all other, non-blank lines
            if not _is_url(line):
                raise PlaylistError(f"Invalid item {line} in playlist {url}")
            playlist.append(PlaylistItem(length=length, title=title, url=line))
            # reset the song variables so it doesn't use the same EXTINF more than once
            length = None
            title = None

    return playlist


async def parse_pls(hass, url):
    """Very simple pls parser.

    Based on https://github.com/mariob/plsparser/blob/master/src/plsparser.py
    """
    pls_data = await _fetch_playlist(hass, url, ())

    pls_parser = configparser.ConfigParser()
    try:
        pls_parser.read_string(pls_data, url)
    except configparser.Error as err:
        raise PlaylistError(f"Can't parse playlist {url}") from err

    if (
        _PLS_SECTION_PLAYLIST not in pls_parser
        or pls_parser[_PLS_SECTION_PLAYLIST].getint("Version") != 2
    ):
        raise PlaylistError(f"Invalid playlist {url}")

    try:
        num_entries = pls_parser.getint(_PLS_SECTION_PLAYLIST, "NumberOfEntries")
    except (configparser.NoOptionError, ValueError) as err:
        raise PlaylistError(f"Invalid NumberOfEntries in playlist {url}") from err

    playlist_section = pls_parser[_PLS_SECTION_PLAYLIST]

    playlist = []
    for entry in range(1, num_entries + 1):
        file_option = f"File{entry}"
        if file_option not in playlist_section:
            _LOGGER.warning("Missing %s in pls from %s", file_option, url)
            continue
        item_url = playlist_section[file_option]
        if not _is_url(item_url):
            raise PlaylistError(f"Invalid item {item_url} in playlist {url}")
        playlist.append(
            PlaylistItem(
                length=playlist_section.get(f"Length{entry}"),
                title=playlist_section.get(f"Title{entry}"),
                url=item_url,
            )
        )
    return playlist


async def parse_playlist(hass, url):
    """Parse an m3u or pls playlist."""
    if url.endswith((".m3u", ".m3u8")):
        playlist = await parse_m3u(hass, url)
    else:
        playlist = await parse_pls(hass, url)

    if not playlist:
        raise PlaylistError(f"Empty playlist {url}")

    return playlist