music-assistant-server

1"""
2Protocol Linking Mixin for the Player Controller.
3
4Handles all logic for linking protocol players (AirPlay, Chromecast, DLNA) to
5native players or wrapping them in Universal Players.
6
7This module provides the ProtocolLinkingMixin class which is inherited by
8PlayerController to add protocol linking capabilities.
9"""
10
11from __future__ import annotations
12
13import asyncio
14import logging
15from contextlib import suppress
16from copy import deepcopy
17from typing import TYPE_CHECKING, cast
18
19from music_assistant_models.enums import (
20    EventType,
21    IdentifierType,
22    PlaybackState,
23    PlayerFeature,
24    PlayerType,
25    ProviderType,
26)
27from music_assistant_models.errors import PlayerCommandFailed, PlayerUnavailableError
28
29from music_assistant.constants import (
30    CONF_CACHED_ARP_MAC,
31    CONF_GROUP_MEMBERS,
32    CONF_LINKED_PROTOCOL_IDS,
33    CONF_PLAYER_DSP,
34    CONF_PLAYER_QUEUES,
35    CONF_PLAYERS,
36    CONF_PREFERRED_OUTPUT_PROTOCOL,
37    CONF_PROTOCOL_KEY_SPLITTER,
38    CONF_PROTOCOL_PARENT_ID,
39    CONF_REPORTED_MAC,
40    CONF_UNDERLYING_PLAYER_ID,
41    PROTOCOL_PRIORITY,
42    VERBOSE_LOG_LEVEL,
43)
44from music_assistant.helpers.util import (
45    is_locally_administered_mac,
46    is_valid_mac_address,
47    normalize_mac_for_matching,
48)
49from music_assistant.models.player import LinkedOutputProtocol, Player
50from music_assistant.providers.sync_group.constants import CONF_ALLOWED_MEMBERS
51from music_assistant.providers.universal_player import UniversalPlayer, UniversalPlayerProvider
52from music_assistant.providers.universal_player.constants import (
53    CONF_CREATED_AT,
54    CONF_DEVICE_IDENTIFIERS,
55    CONF_DEVICE_INFO,
56)
57
58if TYPE_CHECKING:
59    from collections.abc import Coroutine
60    from typing import Any
61
62    from music_assistant_models.player import OutputProtocol
63
64    from music_assistant import MusicAssistant
65
66# Config value keys that are bookkeeping of the universal player wrapper itself
67# (protocol links, device-identity caches and its creation moment) and must never
68# be carried over when a native player replaces a universal player, or when one
69# universal player absorbs another.
70UNIVERSAL_PLAYER_INTERNAL_CONF_KEYS = (
71    CONF_LINKED_PROTOCOL_IDS,
72    CONF_PROTOCOL_PARENT_ID,
73    CONF_UNDERLYING_PLAYER_ID,
74    CONF_DEVICE_IDENTIFIERS,
75    CONF_DEVICE_INFO,
76    CONF_CACHED_ARP_MAC,
77    CONF_REPORTED_MAC,
78    CONF_CREATED_AT,
79)
80
81
82class ProtocolLinkingMixin:
83    """
84    Mixin class providing protocol linking functionality for PlayerController.
85
86    Handles the complex logic of:
87    - Matching protocol players to native players via device identifiers
88    - Creating Universal Players for devices without native support
89    - Managing protocol links and their lifecycle
90    - Selecting the best output protocol for playback
91
92    This mixin expects to be mixed with a class that provides:
93    - mass: MusicAssistant instance
94    - _players: dict of registered players
95    - _pending_protocol_evaluations: dict of pending protocol evaluations
96    - logger: logging.Logger instance
97    - all(): method to get all players
98    - get(): method to get a player by ID
99    - unregister(): method to unregister a player
100    """
101
102    # Type hints for attributes provided by the class this mixin is used with
103    if TYPE_CHECKING:
104        mass: MusicAssistant
105        _players: dict[str, Player]
106        _pending_protocol_evaluations: dict[str, asyncio.TimerHandle]
107        _delayed_evaluation_lock: asyncio.Lock
108        logger: logging.Logger
109
110        def all_players(  # noqa: D102
111            self,
112            return_unavailable: bool = True,
113            return_disabled: bool = False,
114            provider_filter: str | None = None,
115            return_protocol_players: bool = False,
116        ) -> list[Player]: ...
117
118        def get_player(self, player_id: str) -> Player | None: ...  # noqa: D102
119
120        def unregister(  # noqa: D102
121            self,
122            player_id: str,
123            permanent: bool = False,
124            replacement_player_id: str | None = None,
125        ) -> Coroutine[Any, Any, None]: ...
126
127    def _is_protocol_player(self, player: Player) -> bool:
128        """
129        Check if a player is a generic protocol player without native support.
130
131        Protocol players have PlayerType.PROTOCOL set by their provider, indicating
132        they are generic streaming endpoints (e.g., AirPlay receiver, Chromecast device)
133        without vendor-specific native support in Music Assistant.
134        """
135        return player.state.type == PlayerType.PROTOCOL
136
137    def _evaluate_protocol_links(self, player: Player) -> None:
138        """
139        Evaluate and establish protocol links for a player.
140
141        Called when a player is registered to:
142        1. If it's from a protocol provider - try to link to a native player.
143        2. If it's a native player - try to link any existing protocol players.
144        """
145        if player.state.type == PlayerType.PROTOCOL:
146            # Protocol player: try to find a native parent
147            self._try_link_protocol_to_native(player)
148        elif player.state.type == PlayerType.GROUP:
149            return
150        else:
151            # A player that registers with a non-protocol type can no longer be a
152            # protocol child: drop a leftover persisted parent link (e.g. from a
153            # bridge client that turned web player) so the startup repair pass
154            # doesn't heal its player type back to protocol.
155            if self._get_cached_protocol_parent_id(player.player_id):
156                self._clear_protocol_parent_id(player.player_id)
157            # Native player (including STEREO_PAIR): try to find protocol players to link
158            self._try_link_protocols_to_native(player)
159
160    def _try_link_protocol_to_native(self, protocol_player: Player) -> None:
161        """Try to link a protocol player to a native player."""
162        protocol_domain = protocol_player.provider.domain
163
164        # Derived protocol players (e.g. Sendspin bridges riding on another
165        # protocol) resolve strictly via their underlying player - no identifier
166        # matching or delayed evaluation. If the underlying player has no parent
167        # yet, the link is established by _link_derived_protocols_of as soon as
168        # the underlying player gets linked.
169        if protocol_player.underlying_player_id:
170            self._try_link_derived_protocol(protocol_player)
171            return
172
173        # Check for cached parent_id from previous session and restore link immediately
174        cached_parent_id = self._get_cached_protocol_parent_id(protocol_player.player_id)
175        if cached_parent_id:
176            result = self._try_restore_cached_parent(
177                protocol_player, cached_parent_id, protocol_domain
178            )
179            if result:
180                return
181            # Link was refused or parent has active domain - fall through to search
182
183        # Look for a matching native player
184        if self._try_link_to_existing_player(protocol_player, protocol_domain):
185            return
186
187        # No native player found - schedule delayed evaluation to allow other protocols to register
188        if not protocol_player.protocol_parent_id:
189            self._schedule_protocol_evaluation(protocol_player)
190
191    def _try_restore_cached_parent(
192        self, protocol_player: Player, cached_parent_id: str, protocol_domain: str
193    ) -> bool:
194        """
195        Try to restore a cached parent link from a previous session.
196
197        :param protocol_player: The protocol player to link.
198        :param cached_parent_id: The cached parent player ID.
199        :param protocol_domain: The protocol domain (e.g., "airplay").
200        :return: True if handled (linked or waiting), False if should fall through.
201        """
202        if parent_player := self.get_player(cached_parent_id):
203            if parent_player.state.type == PlayerType.GROUP:
204                self._clear_protocol_parent_id(protocol_player.player_id)
205                return False
206            already_linked = any(
207                link.output_protocol_id == protocol_player.player_id
208                for link in parent_player.linked_output_protocols
209            )
210            if already_linked:
211                # Already linked from a previous call - just restore parent and identifiers
212                protocol_player.set_protocol_parent_id(cached_parent_id)
213            else:
214                # Try to add the link (may be refused if domain already has active link)
215                self._add_protocol_link(parent_player, protocol_player, protocol_domain)
216            if protocol_player.protocol_parent_id:
217                protocol_player.refresh_state()
218                parent_player.refresh_state()
219                # Merge the protocol player's identifiers into the universal player
220                # so identifiers discovered since the last persist (e.g. an
221                # ARP-resolved MAC) are included and new protocol players
222                # (like Sendspin bridges) can match via identifiers.
223                if parent_player.provider.domain == "universal_player" and isinstance(
224                    parent_player, UniversalPlayer
225                ):
226                    for conn_type, value in protocol_player.device_info.identifiers.items():
227                        parent_player.device_info.add_identifier(conn_type, value)
228                    self._update_universal_device_info(parent_player, protocol_player)
229                    # Check if this universal player should now be merged with another
230                    # (e.g., DLNA brought a MAC via ARP that matches an AirPlay universal)
231                    self._check_merge_universal_players(parent_player)
232                return True
233            # Link was refused (domain already active on parent) - fall through
234            return False
235
236        # Parent is not registered yet. Leave the protocol player unparented
237        # so the caller schedules delayed evaluation, which can wait for the
238        # cached parent without stranding the protocol player on a dangling id.
239        return False
240
241    def _try_link_to_existing_player(self, protocol_player: Player, protocol_domain: str) -> bool:
242        """
243        Try to link a protocol player to an existing native or universal player.
244
245        :param protocol_player: The protocol player to link.
246        :param protocol_domain: The protocol domain (e.g., "airplay").
247        :return: True if linked successfully, False if no match found.
248        """
249        # Protocol players should only link to:
250        # 1. True native players (Sonos, etc.)
251        # 2. Universal players
252        # NOT to other protocol players (they get merged via universal_player)
253        for native_player in self.all_players(return_protocol_players=False):
254            if native_player.player_id == protocol_player.player_id:
255                continue
256            if native_player.state.type in (PlayerType.PROTOCOL, PlayerType.GROUP):
257                continue
258
259            # For universal players, check if this protocol player is in its stored list
260            # or if identifiers match (for new protocol players like Sendspin bridges
261            # that weren't previously known to the Universal Player)
262            if native_player.provider.domain == "universal_player":
263                if isinstance(native_player, UniversalPlayer):
264                    is_known = protocol_player.player_id in native_player._protocol_player_ids
265                    is_match = not is_known and self._identifiers_match(
266                        native_player, protocol_player, protocol_domain
267                    )
268                    if is_known or is_match:
269                        self._add_protocol_link(native_player, protocol_player, protocol_domain)
270                        # Check if linking actually succeeded (may be refused for
271                        # duplicate domain)
272                        if not protocol_player.protocol_parent_id:
273                            continue
274                        # Merge the protocol player's identifiers into the universal
275                        # player so newly discovered identifiers are included as well
276                        for conn_type, value in protocol_player.device_info.identifiers.items():
277                            native_player.device_info.add_identifier(conn_type, value)
278                        # Update model/manufacturer if universal player has generic values
279                        self._update_universal_device_info(native_player, protocol_player)
280                        # Register newly matched protocol player with the universal player
281                        if is_match:
282                            native_player.add_protocol_player(protocol_player.player_id)
283                        # Persist updated data to config (async via task)
284                        self._save_universal_player_data(native_player)
285                        # Check if this universal player should now be merged with another
286                        self._check_merge_universal_players(native_player)
287                        protocol_player.refresh_state()
288                        native_player.refresh_state()
289                        return True
290                continue
291
292            # Check cached protocol IDs first for fast matching on restart
293            cached_ids = self._get_cached_protocol_ids(native_player.player_id)
294            if protocol_player.player_id in cached_ids:
295                self._add_protocol_link(native_player, protocol_player, protocol_domain)
296                if protocol_player.protocol_parent_id:
297                    protocol_player.refresh_state()
298                    native_player.refresh_state()
299                    return True
300                # Link refused (domain duplicate) - try next native player
301                continue
302
303            # Fallback to identifier matching
304            if self._identifiers_match(native_player, protocol_player, protocol_domain):
305                self._add_protocol_link(native_player, protocol_player, protocol_domain)
306                if protocol_player.protocol_parent_id:
307                    protocol_player.refresh_state()
308                    native_player.refresh_state()
309                    return True
310                # Link refused (domain duplicate) - try next native player
311                continue
312
313            # Final fallback: check if any already-linked protocol player on this native
314            # player shares identifiers with the new protocol player ("sibling matching").
315            # This handles native players (e.g., HEOS) that don't have their own MAC/serial
316            # identifiers but have protocol players (e.g., AirPlay) from the same device
317            # that do share identifiers with the new protocol player (e.g., Sendspin bridge).
318            if self._match_via_linked_protocols(native_player, protocol_player, protocol_domain):
319                return True
320
321        return False
322
323    def _match_via_linked_protocols(
324        self,
325        native_player: Player,
326        protocol_player: Player,
327        protocol_domain: str,
328    ) -> bool:
329        """
330        Try to match a protocol player to a native player via sibling protocol identifiers.
331
332        Check if any of the native player's already-linked protocol players share
333        identifiers with the new protocol player. This handles native players that lack
334        their own device identifiers but have sibling protocols from the same physical device.
335
336        :param native_player: The native player to potentially link to.
337        :param protocol_player: The new protocol player to link.
338        :param protocol_domain: The protocol domain of the new player.
339        :return: True if linked successfully, False if no match found.
340        """
341        for linked in native_player.linked_output_protocols:
342            linked_player = self.get_player(linked.output_protocol_id)
343            if not linked_player:
344                continue
345            if self._identifiers_match(linked_player, protocol_player, protocol_domain):
346                self._add_protocol_link(native_player, protocol_player, protocol_domain)
347                if protocol_player.protocol_parent_id:
348                    protocol_player.refresh_state()
349                    native_player.refresh_state()
350                    return True
351                # Link refused (domain duplicate) - stop checking siblings
352                break
353        return False
354
355    def _try_link_derived_protocol(self, protocol_player: Player) -> bool:
356        """
357        Link a derived protocol player to the parent of its underlying player.
358
359        Derived protocol players carry an underlying_player_id declared by their
360        bridge, which makes the parent resolution deterministic: they always join
361        the parent of the player they ride on (or that player itself when it is
362        not a protocol player). Callers must ensure the player is not linked yet.
363
364        :param protocol_player: The derived protocol player to link.
365        :return: True if the player got linked, False if the underlying player
366            (or its parent) is not available yet or the link was refused.
367        """
368        underlying = self.get_player(protocol_player.underlying_player_id or "")
369        if underlying is None:
370            return False
371        if underlying.state.type == PlayerType.PROTOCOL:
372            parent = (
373                self.get_player(underlying.protocol_parent_id)
374                if underlying.protocol_parent_id
375                else None
376            )
377        else:
378            parent = underlying
379        if parent is None or parent.state.type == PlayerType.GROUP:
380            return False
381
382        self._add_protocol_link(parent, protocol_player, protocol_player.provider.domain)
383        if not protocol_player.protocol_parent_id:
384            # Link refused (e.g. parent already has an active link from this domain)
385            return False
386
387        if parent.provider.domain == "universal_player" and isinstance(parent, UniversalPlayer):
388            # Track membership and identifiers on the universal player so the
389            # derived protocol restores quickly on the next start.
390            parent.add_protocol_player(protocol_player.player_id)
391            for conn_type, value in protocol_player.device_info.identifiers.items():
392                parent.device_info.add_identifier(conn_type, value)
393            self._save_universal_player_data(parent)
394
395        protocol_player.refresh_state()
396        parent.refresh_state()
397        self.logger.debug(
398            "Linked derived protocol %s to %s (via underlying %s)",
399            protocol_player.player_id,
400            parent.player_id,
401            underlying.player_id,
402        )
403        return True
404
405    def _link_derived_protocols_of(self, underlying_player: Player) -> None:
406        """
407        Link any waiting derived protocol players that ride on the given player.
408
409        Called after a player is linked to a parent (or registered as a native
410        player), so derived protocol players that registered earlier can join
411        the same parent.
412        """
413        for candidate in self.all_players(return_protocol_players=True):
414            if candidate.underlying_player_id != underlying_player.player_id:
415                continue
416            if candidate.protocol_parent_id:
417                continue
418            self._try_link_derived_protocol(candidate)
419
420    def _schedule_protocol_evaluation(self, protocol_player: Player) -> None:
421        """
422        Schedule a delayed protocol evaluation.
423
424        Delays evaluation to allow other protocol players and native players to register.
425        Uses a longer delay (30s) if this protocol player was previously linked to a native
426        player that hasn't registered yet, giving native providers time to start up.
427        """
428        player_id = protocol_player.player_id
429
430        # Cancel any existing pending evaluation for this player
431        if player_id in self._pending_protocol_evaluations:
432            self._pending_protocol_evaluations[player_id].cancel()
433
434        # Check if this protocol player has a cached parent (was previously linked)
435        cached_parent_id = self._get_cached_protocol_parent_id(player_id)
436        if cached_parent_id and not self.get_player(cached_parent_id):
437            # Previously linked to a native player that hasn't registered yet
438            # Use longer delay to give native providers time to start up
439            delay = 45.0
440            self.logger.debug(
441                "Protocol player %s waiting for cached parent %s (45s delay)",
442                player_id,
443                cached_parent_id,
444            )
445        else:
446            # Standard delay for protocol player discovery
447            # Allows time for other protocols and native players to register
448            delay = 15.0
449
450        # Schedule evaluation after the delay
451        handle = self.mass.loop.call_later(
452            delay,
453            lambda: self.mass.create_task(self._delayed_protocol_evaluation(player_id)),
454        )
455        self._pending_protocol_evaluations[player_id] = handle
456
457    async def _delayed_protocol_evaluation(self, player_id: str) -> None:
458        """
459        Perform delayed protocol evaluation.
460
461        Called after a delay to allow all protocol players for a device to register.
462        Decides whether to create a universal player, join an existing one, or
463        promote a single protocol player directly.
464
465        Uses a shared lock to serialize evaluations - multiple protocol players from the
466        same device may trigger concurrent evaluations that would otherwise race each other.
467        """
468        self._pending_protocol_evaluations.pop(player_id, None)
469
470        async with self._delayed_evaluation_lock:
471            protocol_player = self.get_player(player_id)
472            if not protocol_player or protocol_player.protocol_parent_id:
473                return
474            if protocol_player.state.type != PlayerType.PROTOCOL:
475                # The player changed type while the evaluation was pending
476                # (e.g. re-registered as a regular player); it must never be
477                # linked as a protocol or wrapped in a universal player.
478                return
479
480            # Derived protocol players resolve strictly via their underlying
481            # player and never match by identifiers or wrap into universal
482            # players; they wait for _link_derived_protocols_of otherwise.
483            if protocol_player.underlying_player_id:
484                self._try_link_derived_protocol(protocol_player)
485                return
486
487            protocol_domain = protocol_player.provider.domain
488
489            # Re-try linking to an existing native/universal player
490            if self._try_link_to_existing_player(protocol_player, protocol_domain):
491                return
492
493            # Check if there's an existing universal player we should join
494            if existing_universal := self._find_matching_universal_player(protocol_player):
495                await self._add_protocol_to_existing_universal(
496                    existing_universal, protocol_player, protocol_domain
497                )
498                if protocol_player.protocol_parent_id is not None:
499                    return
500                # Link refused (domain duplicate) - fall through to create separate UP
501
502            # Refuse to create a universal player wrapper when the cached parent
503            # config exists but is disabled. The user explicitly turned the
504            # parent device off; surfacing its protocols as a separate player
505            # would defeat that intent.
506            cached_parent_id = self._get_cached_protocol_parent_id(player_id)
507            if cached_parent_id:
508                parent_raw = self.mass.config.get(f"{CONF_PLAYERS}/{cached_parent_id}")
509                if parent_raw and not parent_raw.get("enabled", True):
510                    self.logger.debug(
511                        "Skipping universal player creation for %s: cached parent %s is disabled",
512                        player_id,
513                        cached_parent_id,
514                    )
515                    return
516
517            # Find all protocol players that match this device's identifiers
518            matching_protocols = self._find_matching_protocol_players(protocol_player)
519
520            # Create or update UniversalPlayer for all protocol players
521            await self._create_or_update_universal_player(matching_protocols)
522
523    def _find_matching_protocol_players(self, protocol_player: Player) -> list[Player]:
524        """
525        Find all protocol players that match the same device as the given player.
526
527        Searches through all registered protocol players to find ones that share
528        identifiers (MAC, IP, UUID) with the given player, indicating they represent
529        the same physical device.
530        """
531        matching = [protocol_player]
532        protocol_domain = protocol_player.provider.domain
533
534        for other_player in self.all_players(return_protocol_players=True):
535            if other_player.player_id == protocol_player.player_id:
536                continue
537            if other_player.state.type != PlayerType.PROTOCOL:
538                continue
539            if other_player.protocol_parent_id:
540                continue
541            if other_player.underlying_player_id:
542                # Derived protocol players follow their underlying player
543                # once it is linked; they never seed a universal player.
544                continue
545            # Skip players from the same protocol domain
546            # Multiple instances of the same protocol on one host are separate players
547            if other_player.provider.domain == protocol_domain:
548                continue
549            if self._identifiers_match(protocol_player, other_player):
550                matching.append(other_player)
551
552        return matching
553
554    def _find_matching_universal_player(self, protocol_player: Player) -> Player | None:
555        """Find an existing universal player that matches this protocol player."""
556        for player in self._players.values():
557            if not isinstance(player, UniversalPlayer):
558                continue
559            if self._identifiers_match(protocol_player, player, ""):
560                return player
561        return None
562
563    async def _add_protocol_to_existing_universal(
564        self, universal_player: Player, protocol_player: Player, protocol_domain: str
565    ) -> None:
566        """Add a protocol player to an existing universal player."""
567        # Refuse if the universal player already has a registered player from this domain.
568        # This prevents a second instance (e.g., two snapcast players on the same host)
569        # from replacing the first. The caller falls through to create a separate UP.
570        for link in universal_player.linked_output_protocols:
571            if link.protocol_domain == protocol_domain and self.get_player(link.output_protocol_id):
572                return
573
574        self._add_protocol_link(universal_player, protocol_player, protocol_domain)
575
576        # Check if linking actually succeeded (may be refused for duplicate domain)
577        if not protocol_player.protocol_parent_id:
578            return
579
580        if isinstance(universal_player, UniversalPlayer):
581            universal_player.add_protocol_player(protocol_player.player_id)
582            for conn_type, value in protocol_player.device_info.identifiers.items():
583                universal_player.device_info.add_identifier(conn_type, value)
584            # Update model/manufacturer if universal player has generic values
585            self._update_universal_device_info(universal_player, protocol_player)
586
587            # Persist all player data (protocol IDs, identifiers, device info) to config
588            for provider in self.mass.get_providers(ProviderType.PLAYER):
589                if provider.domain == "universal_player":
590                    await cast("UniversalPlayerProvider", provider)._save_player_data(
591                        universal_player.player_id, universal_player
592                    )
593                    break
594
595            # Check if this universal player should now be merged with another
596            self._check_merge_universal_players(universal_player)
597
598        protocol_player.refresh_state()
599        universal_player.refresh_state()
600
601    def _update_universal_device_info(
602        self, universal_player: UniversalPlayer, protocol_player: Player
603    ) -> None:
604        """
605        Update universal player's device info from protocol player if needed.
606
607        A universal player carries generic placeholder device info
608        (model="Universal Player", manufacturer="Music Assistant") when no real
609        values are known for it (yet). This method updates those values from a
610        protocol player that has real device info.
611        """
612        # Check if universal player has generic placeholder device info
613        device_info = universal_player.device_info
614        protocol_info = protocol_player.device_info
615
616        # Update model if universal player has generic value
617        if device_info.model in (None, "Universal Player") and protocol_info.model:
618            device_info.model = protocol_info.model
619
620        # Update manufacturer if universal player has generic value
621        if device_info.manufacturer in (None, "Music Assistant") and protocol_info.manufacturer:
622            device_info.manufacturer = protocol_info.manufacturer
623
624    def _save_universal_player_data(self, universal_player: UniversalPlayer) -> None:
625        """
626        Save universal player data to config via background task.
627
628        This is a helper to persist player data from synchronous code.
629        """
630
631        async def _do_save() -> None:
632            for provider in self.mass.get_providers(ProviderType.PLAYER):
633                if provider.domain == "universal_player":
634                    await cast("UniversalPlayerProvider", provider)._save_player_data(
635                        universal_player.player_id, universal_player
636                    )
637                    break
638
639        self.mass.create_task(_do_save())
640
641    def _get_known_protocol_ids(self, parent: Player) -> list[str]:
642        """
643        Get all protocol IDs tracked for a parent player.
644
645        Includes both active links and cached/inactive protocol IDs so callers can
646        safely migrate or clean up the full parent/protocol relationship.
647        """
648        result: list[str] = []
649        seen: set[str] = set()
650
651        for linked in parent.linked_output_protocols:
652            if linked.output_protocol_id not in seen:
653                result.append(linked.output_protocol_id)
654                seen.add(linked.output_protocol_id)
655
656        if parent.provider.domain == "universal_player" and isinstance(parent, UniversalPlayer):
657            cached_ids = parent._protocol_player_ids
658        else:
659            cached_ids = self._get_cached_protocol_ids(parent.player_id)
660
661        for protocol_id in cached_ids:
662            if protocol_id not in seen:
663                result.append(protocol_id)
664                seen.add(protocol_id)
665
666        return result
667
668    def _migrate_protocol_ids_to_parent(self, parent: Player, protocol_ids: set[str]) -> None:
669        """
670        Persist protocol ownership on a new parent without requiring active links.
671
672        This is used when protocol ownership moves from one parent to another during
673        promotion/merge flows. Active protocols are already linked in memory, but
674        disabled or temporarily unavailable protocols still need their cached parent
675        relationship moved as well.
676        """
677        if not protocol_ids:
678            return
679
680        if parent.provider.domain == "universal_player" and isinstance(parent, UniversalPlayer):
681            for protocol_id in protocol_ids:
682                parent.add_protocol_player(protocol_id)
683            self._save_universal_player_data(parent)
684        else:
685            conf_key = f"{CONF_PLAYERS}/{parent.player_id}/values/{CONF_LINKED_PROTOCOL_IDS}"
686            cached_ids = self._get_cached_protocol_ids(parent.player_id)
687            changed = False
688            for protocol_id in protocol_ids:
689                if protocol_id not in cached_ids:
690                    cached_ids.append(protocol_id)
691                    changed = True
692            if changed:
693                self.mass.config.set(conf_key, cached_ids)
694
695        for protocol_id in protocol_ids:
696            if self.mass.config.get(f"{CONF_PLAYERS}/{protocol_id}"):
697                self._save_protocol_parent_id(protocol_id, parent.player_id)
698
699    def _remove_protocol_ids_from_parent(self, parent: Player, protocol_ids: set[str]) -> None:
700        """
701        Remove protocol ownership from a parent before it is permanently cleaned up.
702
703        This prevents `_cleanup_protocol_links` from treating already-migrated
704        protocols as orphaned when the obsolete parent is unregistered.
705        """
706        if not protocol_ids:
707            return
708
709        remaining_links = [
710            link
711            for link in parent.linked_output_protocols
712            if link.output_protocol_id not in protocol_ids
713        ]
714        if len(remaining_links) != len(parent.linked_output_protocols):
715            parent.set_linked_output_protocols(remaining_links)
716
717        if parent.provider.domain == "universal_player" and isinstance(parent, UniversalPlayer):
718            for protocol_id in protocol_ids:
719                parent.remove_protocol_player(protocol_id)
720            if self.mass.config.get(f"{CONF_PLAYERS}/{parent.player_id}"):
721                self.mass.config.set(
722                    f"{CONF_PLAYERS}/{parent.player_id}/values/{CONF_LINKED_PROTOCOL_IDS}",
723                    parent._protocol_player_ids,
724                )
725        else:
726            for protocol_id in protocol_ids:
727                self._remove_protocol_id_from_cache(parent.player_id, protocol_id)
728
729    def _check_merge_universal_players(self, universal_player: UniversalPlayer) -> None:
730        """
731        Check if another universal player should be merged into this one.
732
733        Called after identifiers are copied from a protocol player to a universal player.
734        When a protocol player brings new identifiers (e.g., MAC from ARP enrichment),
735        the universal player may now match another universal player that was created
736        from a different protocol (e.g., DLNA-based universal player now matches
737        AirPlay-based universal player because they share the same MAC address).
738
739        The oldest universal player absorbs the other one. Only one merge is performed
740        per call; re-evaluation will catch cascading merges.
741        """
742        if not (match := self._find_mergeable_universal_player(universal_player)):
743            return
744        keep, remove = self._select_merge_winner(universal_player, match)
745        self.logger.info(
746            "Merging universal player %s into %s (shared identifiers)",
747            remove.player_id,
748            keep.player_id,
749        )
750        self._merge_universal_players(keep, remove)
751
752    def _find_mergeable_universal_player(
753        self, universal_player: UniversalPlayer
754    ) -> UniversalPlayer | None:
755        """
756        Return the first other universal player that represents the same device, if any.
757
758        Players that share a protocol domain are not returned: they are separate devices
759        that merely share an identifier, so merging them would orphan a protocol.
760
761        :param universal_player: The universal player to find a merge candidate for.
762        """
763        for player in list(self._players.values()):
764            if player.provider.domain != "universal_player":
765                continue
766            if player.player_id == universal_player.player_id:
767                continue
768            if not isinstance(player, UniversalPlayer):
769                continue
770
771            if not self._identifiers_match(universal_player, player, ""):
772                continue
773
774            # Do not merge if both UPs have protocols from the same domain.
775            # Multiple instances of the same protocol on one host (e.g., several
776            # squeezelite players on the same VM) are separate devices that happen
777            # to share an IP. Merging them would orphan one instance's protocol.
778            domains_a = {
779                link.protocol_domain
780                for link in universal_player.linked_output_protocols
781                if link.protocol_domain
782            }
783            domains_b = {
784                link.protocol_domain
785                for link in player.linked_output_protocols
786                if link.protocol_domain
787            }
788            if domains_a & domains_b:
789                self.logger.debug(
790                    "Skipping merge of %s and %s: shared protocol domain(s) %s",
791                    universal_player.player_id,
792                    player.player_id,
793                    domains_a & domains_b,
794                )
795                continue
796
797            return player
798
799        return None
800
801    def _select_merge_winner(
802        self, universal_player: UniversalPlayer, other_player: UniversalPlayer
803    ) -> tuple[UniversalPlayer, UniversalPlayer]:
804        """
805        Return which of the two universal players absorbs the other, as (keeper, absorbed).
806
807        The oldest player wins, on a tie the one with the most protocol links.
808
809        :param universal_player: The universal player the merge was triggered for.
810        :param other_player: The universal player it matched with.
811        """
812        # The outcome must be stable across server restarts. Without that, which
813        # UniversalPlayer "wins" depends on iteration order of self._players.values(),
814        # which can shift between runs and causes downstream player_id reshuffling
815        # (and broken entity bindings in consumers like the Home Assistant MA integration).
816        if self._merge_rank(universal_player) <= self._merge_rank(other_player):
817            return universal_player, other_player
818        return other_player, universal_player
819
820    def _merge_rank(self, universal_player: Player) -> tuple[int, int, str]:
821        """
822        Return the sort key of a universal player in a merge, lowest wins.
823
824        Age comes first because the keeper's player id is the one that survives, and the
825        oldest player is the one API consumers have been bound to the longest. The links
826        of the absorbed player move over either way, so nothing is lost by keeping the
827        smaller one. A player from before player ids were minted has no stored moment and
828        counts as the oldest, which is exactly what it is.
829        """
830        created_at = self.mass.config.get(
831            f"{CONF_PLAYERS}/{universal_player.player_id}/values/{CONF_CREATED_AT}", 0
832        )
833        return (
834            created_at if isinstance(created_at, int) else 0,
835            -len(universal_player.linked_output_protocols),
836            universal_player.player_id,
837        )
838
839    def _merge_universal_players(self, keep: UniversalPlayer, remove: UniversalPlayer) -> None:
840        """
841        Absorb one universal player into another and schedule the absorbed one's removal.
842
843        :param keep: The universal player that stays.
844        :param remove: The universal player that is absorbed.
845        """
846        known_protocol_ids = set(self._get_known_protocol_ids(remove))
847        active_protocol_ids = {link.output_protocol_id for link in remove.linked_output_protocols}
848        moved_protocol_ids: set[str] = set()
849
850        # Transfer protocol links from the removed player to the keeper
851        for linked in list(remove.linked_output_protocols):
852            if protocol_player := self.get_player(linked.output_protocol_id):
853                protocol_player.set_protocol_parent_id(None)
854                domain = linked.protocol_domain or protocol_player.provider.domain
855
856                # Check if keeper already has an active link from this domain
857                if self._parent_has_active_protocol_from_domain(keep, domain):
858                    self.logger.debug(
859                        "Skipping duplicate %s link during merge: %s",
860                        domain,
861                        linked.output_protocol_id,
862                    )
863                    continue
864
865                self._add_protocol_link(keep, protocol_player, domain)
866                if protocol_player.protocol_parent_id == keep.player_id:
867                    moved_protocol_ids.add(protocol_player.player_id)
868                    protocol_player.refresh_state()
869
870        # Move cached-only protocol ownership as well so old-parent cleanup
871        # does not wipe protocols that were intentionally preserved.
872        cached_only_ids = known_protocol_ids - active_protocol_ids
873        preserved_protocol_ids = moved_protocol_ids | cached_only_ids
874        self._migrate_protocol_ids_to_parent(keep, preserved_protocol_ids)
875        self._remove_protocol_ids_from_parent(remove, preserved_protocol_ids)
876
877        # Merge identifiers
878        for conn_type, value in remove.device_info.identifiers.items():
879            keep.device_info.add_identifier(conn_type, value)
880        keep.refresh_state()
881
882        # Persist updated data before the obsolete player is removed
883        self._save_universal_player_data(keep)
884
885        # Carry over the user's configuration and re-point group memberships
886        # before the permanent removal below deletes the losing wrapper's config
887        self._migrate_universal_player_config(remove.player_id, keep.player_id)
888        self._repoint_group_memberships(remove.player_id, keep.player_id)
889
890        # Stop playback and remove the obsolete player
891        self.mass.create_task(self._stop_and_unregister(remove, keep.player_id))
892
893    def _link_protocols_to_universal(
894        self, universal_player: Player, protocol_players: list[Player]
895    ) -> None:
896        """Link protocol players to a universal player, cleaning up existing links."""
897        for player in protocol_players:
898            # Clean up if linked to another player
899            if player.protocol_parent_id:
900                if parent := self.get_player(player.protocol_parent_id):
901                    self._remove_protocol_link(parent, player.player_id)
902                player.set_protocol_parent_id(None)
903            # Link to universal player
904            self._add_protocol_link(universal_player, player, player.provider.domain)
905            player.refresh_state()
906
907        # Update availability from protocol players
908        universal_player.refresh_state()
909
910    async def _create_or_update_universal_player(self, protocol_players: list[Player]) -> None:
911        """
912        Create or update a UniversalPlayer for a set of protocol players.
913
914        Delegates to the universal player provider which handles orchestration,
915        locking, and player creation. The controller then links the protocols
916        to the universal player.
917        """
918        # Filter out players that got linked during the async delay
919        protocol_players = [p for p in protocol_players if not p.protocol_parent_id]
920        if not protocol_players:
921            return
922
923        # Get the universal_player provider
924        universal_provider: UniversalPlayerProvider | None = None
925        for provider in self.mass.get_providers(ProviderType.PLAYER):
926            if provider.domain == "universal_player":
927                universal_provider = cast("UniversalPlayerProvider", provider)
928                break
929
930        if not universal_provider:
931            return
932
933        # Delegate to provider - it handles locking, create/update decision, etc.
934        # It reports which universal player each protocol player belongs to, as a
935        # device with several instances of one protocol domain gets more than one.
936        assignments = await universal_provider.ensure_universal_players_for_protocols(
937            protocol_players
938        )
939
940        # Link the protocols to their universal player (the controller manages
941        # cross-provider state), skipping players that were linked in the meantime.
942        by_universal_player: dict[str, list[Player]] = {}
943        for player in protocol_players:
944            if player.protocol_parent_id:
945                continue
946            if universal_player := assignments.get(player.player_id):
947                by_universal_player.setdefault(universal_player.player_id, []).append(player)
948
949        for universal_player_id, players in by_universal_player.items():
950            if universal_player := self.get_player(universal_player_id):
951                self._link_protocols_to_universal(universal_player, players)
952
953    def _try_link_protocols_to_native(self, native_player: Player) -> None:
954        """Try to link protocol players to a native player."""
955        # First, check if there's a universal player for this device that should be replaced
956        self._check_replace_universal_player(native_player)
957
958        # Look for protocol players that should be linked
959        for protocol_player in self.all_players(return_protocol_players=True):
960            if protocol_player.state.type != PlayerType.PROTOCOL:
961                continue
962            if protocol_player.protocol_parent_id:
963                # Already linked to a parent (could be this native player after replacement)
964                continue
965            if protocol_player.underlying_player_id:
966                # Derived protocol players link via their underlying player instead
967                continue
968
969            protocol_domain = protocol_player.provider.domain
970
971            # Skip if this native player already has an active link from this domain
972            # (prevents a second instance of the same protocol from trying to link)
973            if self._parent_has_active_protocol_from_domain(native_player, protocol_domain):
974                continue
975
976            if self._identifiers_match(native_player, protocol_player, protocol_domain):
977                self._add_protocol_link(native_player, protocol_player, protocol_domain)
978                # Check if linking succeeded (may be refused for duplicate domain)
979                if protocol_player.protocol_parent_id is not None:
980                    protocol_player.refresh_state()
981                    native_player.refresh_state()
982
983        # Proactively recover disabled/missing protocols from config
984        # This ensures disabled protocols show up in the UI so they can be re-enabled
985        self._recover_cached_protocol_links(native_player)
986
987        # Second pass: match remaining unlinked protocol players via sibling identifiers.
988        # After cache recovery, the native player has linked protocols (e.g., AirPlay)
989        # whose identifiers can be used to match new protocol players (e.g., Sendspin bridge)
990        # that share the same device identifiers but couldn't match the native player directly.
991        for protocol_player in self.all_players(return_protocol_players=True):
992            if protocol_player.state.type != PlayerType.PROTOCOL:
993                continue
994            if protocol_player.protocol_parent_id:
995                continue
996            if protocol_player.underlying_player_id:
997                continue
998            protocol_domain = protocol_player.provider.domain
999            if self._parent_has_active_protocol_from_domain(native_player, protocol_domain):
1000                continue
1001            if self._match_via_linked_protocols(native_player, protocol_player, protocol_domain):
1002                self.logger.debug(
1003                    "Linked %s to %s via sibling protocol identifiers",
1004                    protocol_player.player_id,
1005                    native_player.player_id,
1006                )
1007
1008        # Finally, link derived protocol players that ride directly on this
1009        # native player (derived players riding on the protocol players linked
1010        # above are handled by _add_protocol_link itself).
1011        self._link_derived_protocols_of(native_player)
1012
1013    def _check_replace_universal_player(self, native_player: Player) -> None:
1014        """Check if a universal player should be replaced by this native player."""
1015        # Skip if native_player is itself a universal player (prevent self-replacement)
1016        if native_player.provider.domain == "universal_player":
1017            return
1018
1019        # Look for universal players that match this native player
1020        for player in list(self._players.values()):
1021            if player.provider.domain != "universal_player":
1022                continue
1023
1024            # Check by identifiers first
1025            identifiers_match = self._identifiers_match(native_player, player, "")
1026
1027            # Also check if native player's ID is in the universal player's stored protocol list
1028            # This handles players that changed type (e.g., sendspin web players changed from
1029            # PROTOCOL to PLAYER type) and have no identifiers to match against
1030            player_id_in_protocols = (
1031                isinstance(player, UniversalPlayer)
1032                and native_player.player_id in player._protocol_player_ids
1033            )
1034
1035            if not identifiers_match and not player_id_in_protocols:
1036                continue
1037
1038            known_protocol_ids = set(self._get_known_protocol_ids(player))
1039            refused_protocol_ids: set[str] = set()
1040            moved_protocol_ids: set[str] = set()
1041
1042            # Transfer the protocol links from the universal player to the native player.
1043            # A derived protocol rides on another output, so a base and everything riding
1044            # on it can only move together: refusing one of them holds back the group.
1045            for group in self._group_protocol_links(player):
1046                domains = {
1047                    protocol_player.player_id: linked.protocol_domain
1048                    or protocol_player.provider.domain
1049                    for linked, protocol_player in group
1050                }
1051                if any(
1052                    self._parent_has_active_protocol_from_domain(
1053                        native_player, domain, exclude_player_id=protocol_id
1054                    )
1055                    for protocol_id, domain in domains.items()
1056                ):
1057                    refused_protocol_ids.update(domains.keys())
1058                    continue
1059                for _, protocol_player in group:
1060                    protocol_player.set_protocol_parent_id(None)
1061                    self._add_protocol_link(
1062                        native_player, protocol_player, domains[protocol_player.player_id]
1063                    )
1064                    if protocol_player.protocol_parent_id != native_player.player_id:
1065                        # Link refused, keep the protocol owned by the universal player.
1066                        protocol_player.set_protocol_parent_id(player.player_id)
1067                        refused_protocol_ids.add(protocol_player.player_id)
1068                        continue
1069                    protocol_player.refresh_state()
1070                    moved_protocol_ids.add(protocol_player.player_id)
1071
1072            # A refused link leaves the universal player in charge, so only hand over what
1073            # actually moved: ownership that exists in config alone stays with it, which
1074            # keeps a protocol derived from a refused one with the parent it will link to.
1075            migrated_protocol_ids = (
1076                moved_protocol_ids if refused_protocol_ids else known_protocol_ids
1077            )
1078            # A device that kept its id across a type change lists itself here.
1079            # It must never become its own protocol, and it must also be dropped
1080            # from the obsolete universal player so the permanent cleanup below
1081            # doesn't treat it as an orphaned protocol (which would re-wrap the
1082            # native player in a fresh universal player).
1083            migrated_protocol_ids.discard(native_player.player_id)
1084            self._migrate_protocol_ids_to_parent(native_player, migrated_protocol_ids)
1085            self._remove_protocol_ids_from_parent(
1086                player, migrated_protocol_ids | {native_player.player_id}
1087            )
1088            native_player.refresh_state()
1089
1090            if refused_protocol_ids:
1091                # Registered protocols that the native player refused remain on the wrapper.
1092                continue
1093
1094            # Carry over the user's configuration and re-point group memberships
1095            # before the permanent removal below deletes the universal player's config
1096            self._migrate_universal_player_config(player.player_id, native_player.player_id)
1097            self._repoint_group_memberships(player.player_id, native_player.player_id)
1098
1099            # Stop playback and remove the now-obsolete universal player
1100            self.mass.create_task(self._stop_and_unregister(player, native_player.player_id))
1101
1102    def _group_protocol_links(
1103        self, parent: Player
1104    ) -> list[list[tuple[LinkedOutputProtocol, Player]]]:
1105        """
1106        Group a parent's registered protocol links with the protocols riding on them.
1107
1108        Each group holds one base protocol followed by the derived protocols that ride
1109        on it. A protocol whose underlying player is not one of the parent's own links
1110        forms a group of its own.
1111
1112        :param parent: The parent player whose protocol links should be grouped.
1113        """
1114        registered = [
1115            (linked, protocol_player)
1116            for linked in parent.linked_output_protocols
1117            if (protocol_player := self.get_player(linked.output_protocol_id))
1118        ]
1119        link_ids = {protocol_player.player_id for _, protocol_player in registered}
1120        riders: dict[str, list[tuple[LinkedOutputProtocol, Player]]] = {}
1121        bases: list[tuple[LinkedOutputProtocol, Player]] = []
1122        for linked, protocol_player in registered:
1123            underlying_id = protocol_player.underlying_player_id
1124            if underlying_id and underlying_id in link_ids:
1125                riders.setdefault(underlying_id, []).append((linked, protocol_player))
1126            else:
1127                bases.append((linked, protocol_player))
1128
1129        groups = [
1130            [(linked, protocol_player), *riders.get(protocol_player.player_id, [])]
1131            for linked, protocol_player in bases
1132        ]
1133        # A derived protocol riding on another derived protocol has no base group here,
1134        # so it moves on its own rather than being dropped from the transfer.
1135        grouped_ids = {
1136            protocol_player.player_id for group in groups for _, protocol_player in group
1137        }
1138        groups.extend([entry] for entry in registered if entry[1].player_id not in grouped_ids)
1139        return groups
1140
1141    def _migrate_universal_player_config(self, universal_id: str, native_id: str) -> None:
1142        """
1143        Carry over user-set configuration from a replaced universal player.
1144
1145        Copies the custom display name, player config values, DSP settings and
1146        per-queue settings of the (obsolete) universal player onto the native
1147        player that replaces it, without overwriting values explicitly set on
1148        the native player itself. Must be called while the universal player's
1149        config still exists, as the permanent removal deletes it.
1150
1151        :param universal_id: Player id of the obsolete universal player being replaced.
1152        :param native_id: Player id of the native player that replaces it.
1153        """
1154        source_raw = self.mass.config.get(f"{CONF_PLAYERS}/{universal_id}")
1155        source_raw = source_raw if isinstance(source_raw, dict) else {}
1156        target_key = f"{CONF_PLAYERS}/{native_id}"
1157        target_raw = self.mass.config.get(target_key)
1158        target_raw = target_raw if isinstance(target_raw, dict) else {}
1159        player_config_changed = False
1160
1161        # only carry an actual user rename, not the auto-generated default name;
1162        # likewise a name on the native player only counts as a user override when
1163        # it differs from the default name
1164        custom_name = source_raw.get("name")
1165        target_name = target_raw.get("name")
1166        target_has_custom_name = bool(target_name) and target_name != target_raw.get("default_name")
1167        if (
1168            custom_name
1169            and custom_name != source_raw.get("default_name")
1170            and not target_has_custom_name
1171        ):
1172            self.mass.config.set(f"{target_key}/name", custom_name)
1173            player_config_changed = True
1174
1175        source_values = source_raw.get("values")
1176        source_values = source_values if isinstance(source_values, dict) else {}
1177        target_values = target_raw.get("values")
1178        target_values = target_values if isinstance(target_values, dict) else {}
1179        for key, value in source_values.items():
1180            if key in UNIVERSAL_PLAYER_INTERNAL_CONF_KEYS:
1181                continue
1182            if CONF_PROTOCOL_KEY_SPLITTER in key:
1183                # stale virtual mirror of a protocol player's own config
1184                continue
1185            if key in target_values:
1186                continue
1187            self.mass.config.set(f"{target_key}/values/{key}", deepcopy(value))
1188            player_config_changed = True
1189
1190        # DSP settings follow wholesale, unless the native player has its own
1191        dsp_changed = False
1192        source_dsp = self.mass.config.get(f"{CONF_PLAYER_DSP}/{universal_id}")
1193        if source_dsp and not self.mass.config.get(f"{CONF_PLAYER_DSP}/{native_id}"):
1194            self.mass.config.set(f"{CONF_PLAYER_DSP}/{native_id}", deepcopy(source_dsp))
1195            dsp_changed = True
1196
1197        queue_changed = self._migrate_universal_queue_config(universal_id, native_id)
1198
1199        if not (player_config_changed or dsp_changed or queue_changed):
1200            return
1201        self.logger.info(
1202            "Carried over configuration of universal player %s to %s", universal_id, native_id
1203        )
1204        if player_config_changed:
1205            # the native player's in-place config was loaded before the carry-over,
1206            # so reload it to make the migrated values (e.g. custom name) effective
1207            self.mass.create_task(self._reapply_player_config(native_id))
1208
1209    def _migrate_universal_queue_config(self, universal_id: str, native_id: str) -> bool:
1210        """
1211        Move the per-queue settings of a replaced universal player to its replacement.
1212
1213        Queue ids equal player ids, so the source entry is removed once it is carried over.
1214
1215        :param universal_id: Player id of the obsolete universal player.
1216        :param native_id: Player id of the native player that replaces it.
1217        :return: True if any queue setting was carried over.
1218        """
1219        queue_changed = False
1220        source_queue_raw = self.mass.config.get(f"{CONF_PLAYER_QUEUES}/{universal_id}")
1221        source_queue_raw = source_queue_raw if isinstance(source_queue_raw, dict) else None
1222        if source_queue_values := (source_queue_raw or {}).get("values"):
1223            target_queue_key = f"{CONF_PLAYER_QUEUES}/{native_id}"
1224            target_queue_raw = self.mass.config.get(target_queue_key)
1225            target_queue_raw = (
1226                deepcopy(target_queue_raw) if isinstance(target_queue_raw, dict) else {}
1227            )
1228            target_queue_values = target_queue_raw.setdefault("values", {})
1229            for key, value in source_queue_values.items():
1230                if key in target_queue_values:
1231                    continue
1232                target_queue_values[key] = deepcopy(value)
1233                queue_changed = True
1234            if queue_changed:
1235                target_queue_raw["queue_id"] = native_id
1236                self.mass.config.set(target_queue_key, target_queue_raw)
1237        if source_queue_raw is not None:
1238            self.mass.config.remove(f"{CONF_PLAYER_QUEUES}/{universal_id}")
1239        return queue_changed
1240
1241    async def _reapply_player_config(self, player_id: str) -> None:
1242        """Reload the stored config onto a registered player and refresh its state."""
1243        if not (player := self.get_player(player_id)):
1244            return
1245        config = await self.mass.config.get_player_config(player_id)
1246        player.set_config(config)
1247        player.update_state()
1248        self.mass.signal_event(EventType.PLAYER_CONFIG_UPDATED, object_id=player_id, data=config)
1249
1250    def _repoint_group_memberships(self, old_player_id: str, new_player_id: str) -> None:
1251        """
1252        Re-point group memberships from a removed player to its successor.
1253
1254        When a universal player is replaced by a native player or merged into
1255        another universal player, other players that list the removed player as
1256        a group member (or allowed member) must follow its successor so those
1257        memberships are not silently lost. Updates the persisted config and keeps
1258        any registered player whose membership changed in sync.
1259
1260        :param old_player_id: Player id that is being removed.
1261        :param new_player_id: Player id that replaces it.
1262        """
1263        all_player_configs = self.mass.config.get(CONF_PLAYERS, {})
1264        if not isinstance(all_player_configs, dict):
1265            return
1266        for other_id, other_cfg in all_player_configs.items():
1267            if not isinstance(other_cfg, dict):
1268                continue
1269            other_values = other_cfg.get("values")
1270            if not isinstance(other_values, dict):
1271                continue
1272            for key in (CONF_GROUP_MEMBERS, CONF_ALLOWED_MEMBERS):
1273                members = other_values.get(key)
1274                if not isinstance(members, list) or old_player_id not in members:
1275                    continue
1276                new_members: list[str] = []
1277                for member_id in members:
1278                    resolved = new_player_id if member_id == old_player_id else member_id
1279                    if resolved not in new_members:
1280                        new_members.append(resolved)
1281                self.mass.config.set(f"{CONF_PLAYERS}/{other_id}/values/{key}", new_members)
1282                # keep a registered player's in-place config copy and state in sync
1283                if other_player := self.get_player(other_id):
1284                    if entry := other_player.config.values.get(key):
1285                        entry.value = new_members
1286                    other_player.refresh_state()
1287
1288    async def _stop_and_unregister(self, player: Player, replacement_player_id: str) -> None:
1289        """
1290        Stop active playback on a player and then permanently unregister it.
1291
1292        Used when an obsolete universal player is replaced or merged away: while
1293        it is not idle its protocol child keeps playing the dead queue's stream
1294        until the buffer drains, so playback is stopped first. Queue ownership is
1295        intentionally not transferred.
1296
1297        :param player: The obsolete player to stop and permanently remove.
1298        :param replacement_player_id: Player ID that takes the obsolete player's place.
1299        """
1300        if player.playback_state != PlaybackState.IDLE:
1301            with suppress(PlayerCommandFailed, PlayerUnavailableError):
1302                await self.mass.player_queues.stop(player.player_id)
1303        await self.unregister(
1304            player.player_id, permanent=True, replacement_player_id=replacement_player_id
1305        )
1306
1307    def _parent_has_active_protocol_from_domain(
1308        self, parent: Player, domain: str, exclude_player_id: str | None = None
1309    ) -> bool:
1310        """
1311        Check if a parent already has an active (registered) protocol player from a given domain.
1312
1313        This prevents a second protocol player of the same domain (e.g., a second AirPlay
1314        instance on the same host) from replacing the first one's link on the same parent.
1315
1316        :param parent: The parent player to check.
1317        :param domain: The protocol domain to check for (e.g., "airplay", "dlna").
1318        :param exclude_player_id: Optional player ID to exclude from the check
1319            (used when checking if a player's own domain is already linked).
1320        """
1321        for link in parent.linked_output_protocols:
1322            if link.protocol_domain != domain:
1323                continue
1324            if exclude_player_id and link.output_protocol_id == exclude_player_id:
1325                continue
1326            # A registered player from this domain blocks the link, even if unavailable.
1327            # Being offline doesn't make it a different device — it's still occupying
1328            # this domain slot. The provider should remove stale players explicitly.
1329            if self.get_player(link.output_protocol_id):
1330                return True
1331        return False
1332
1333    def _add_protocol_link(
1334        self, native_player: Player, protocol_player: Player, protocol_domain: str
1335    ) -> None:
1336        """Add a protocol link from native player to protocol player."""
1337        # Never link a player to itself (hides it as its own protocol child).
1338        if native_player.player_id == protocol_player.player_id:
1339            return
1340        # Guard: refuse to replace an existing active link from the same domain.
1341        # This prevents a second instance of the same protocol (e.g., two AirPlay
1342        # instances on the same host) from silently replacing the first one.
1343        if self._parent_has_active_protocol_from_domain(
1344            native_player, protocol_domain, exclude_player_id=protocol_player.player_id
1345        ):
1346            self.logger.debug(
1347                "Refusing to link %s to %s: parent already has an active %s link",
1348                protocol_player.player_id,
1349                native_player.player_id,
1350                protocol_domain,
1351            )
1352            return
1353
1354        # Remove any existing link for the same protocol domain
1355        updated_protocols = [
1356            link
1357            for link in native_player.linked_output_protocols
1358            if link.protocol_domain != protocol_domain
1359        ]
1360
1361        # Get priority for this protocol
1362        priority = PROTOCOL_PRIORITY.get(protocol_domain, 100)
1363
1364        # Derived transports (e.g. a Sendspin bridge riding on an AirPlay player)
1365        # reference the base output they run on top of; "native" when they ride
1366        # on the parent player itself
1367        derived_from = protocol_player.underlying_player_id
1368        if derived_from == native_player.player_id:
1369            derived_from = "native"
1370
1371        # Add the new link
1372        updated_protocols.append(
1373            LinkedOutputProtocol(
1374                output_protocol_id=protocol_player.player_id,
1375                protocol_domain=protocol_domain,
1376                priority=priority,
1377                derived_from=derived_from,
1378            )
1379        )
1380        native_player.set_linked_output_protocols(updated_protocols)
1381
1382        # Set protocol player's parent
1383        protocol_player.set_protocol_parent_id(native_player.player_id)
1384
1385        # Persist linked protocol IDs to config for fast restart
1386        # (only for non-universal players, as universal players handle this themselves)
1387        if native_player.provider.domain != "universal_player":
1388            self._save_linked_protocol_ids(native_player)
1389        # Always save the parent ID on the protocol player for reverse lookup on restart
1390        # (needed for both native and universal parents to enable fast restore)
1391        self._save_protocol_parent_id(protocol_player.player_id, native_player.player_id)
1392
1393        # The freshly linked player may have derived protocol players (e.g. a
1394        # Sendspin bridge riding on it) waiting to join the same parent.
1395        self._link_derived_protocols_of(protocol_player)
1396
1397    def _remove_protocol_link(
1398        self, native_player: Player, protocol_player_id: str, permanent: bool = False
1399    ) -> None:
1400        """
1401        Remove a protocol link.
1402
1403        :param native_player: The parent player to remove the link from.
1404        :param protocol_player_id: The protocol player ID to unlink.
1405        :param permanent: If True, also removes the protocol ID from the cached list.
1406            Use this when the protocol player config is being deleted. If False,
1407            the protocol ID remains in the cache so it can be shown as disabled
1408            and re-enabled later.
1409        """
1410        updated_protocols = [
1411            link
1412            for link in native_player.linked_output_protocols
1413            if link.output_protocol_id != protocol_player_id
1414        ]
1415        native_player.set_linked_output_protocols(updated_protocols)
1416
1417        # Clear parent reference on protocol player if it still exists
1418        if protocol_player := self.get_player(protocol_player_id):
1419            if protocol_player.protocol_parent_id == native_player.player_id:
1420                protocol_player.set_protocol_parent_id(None)
1421
1422        # Update persisted linked protocol IDs
1423        if native_player.provider.domain != "universal_player":
1424            if permanent:
1425                # Permanently remove from cache (player config is being deleted)
1426                self._remove_protocol_id_from_cache(native_player.player_id, protocol_player_id)
1427            # Note: we don't call _save_linked_protocol_ids here anymore for non-permanent
1428            # removals because the merge approach will preserve the ID in the cache
1429        # Always clear the cached parent ID (for both native and universal parents)
1430        self._clear_protocol_parent_id(protocol_player_id)
1431
1432    def _save_linked_protocol_ids(self, native_player: Player) -> None:
1433        """
1434        Save linked protocol IDs to config for persistence across restarts.
1435
1436        This method merges active protocol IDs with existing cached IDs to preserve
1437        disabled protocol players in the cache. This allows disabled protocols to be
1438        shown in the UI so they can be re-enabled.
1439        """
1440        conf_key = f"{CONF_PLAYERS}/{native_player.player_id}/values/{CONF_LINKED_PROTOCOL_IDS}"
1441        # Get existing cached IDs to preserve disabled protocols
1442        existing_ids: list[str] = self.mass.config.get(conf_key, [])
1443        # Get currently active protocol IDs
1444        active_ids = {link.output_protocol_id for link in native_player.linked_output_protocols}
1445        # Merge: keep existing IDs and add any new active ones
1446        merged_ids = list(existing_ids)
1447        for protocol_id in active_ids:
1448            if protocol_id not in merged_ids:
1449                merged_ids.append(protocol_id)
1450        self.mass.config.set(conf_key, merged_ids)
1451
1452    def _get_cached_protocol_ids(self, player_id: str) -> list[str]:
1453        """Get cached linked protocol IDs from config."""
1454        conf_key = f"{CONF_PLAYERS}/{player_id}/values/{CONF_LINKED_PROTOCOL_IDS}"
1455        result = self.mass.config.get(conf_key, [])
1456        return list(result) if result else []
1457
1458    def _remove_protocol_id_from_cache(
1459        self, parent_player_id: str, protocol_player_id: str
1460    ) -> None:
1461        """
1462        Permanently remove a protocol player ID from the cached linked protocol IDs.
1463
1464        Use this when a protocol player config is being deleted, not just disabled.
1465        """
1466        conf_key = f"{CONF_PLAYERS}/{parent_player_id}/values/{CONF_LINKED_PROTOCOL_IDS}"
1467        cached_ids: list[str] = self.mass.config.get(conf_key, [])
1468        if protocol_player_id in cached_ids:
1469            cached_ids.remove(protocol_player_id)
1470            self.mass.config.set(conf_key, cached_ids)
1471
1472    def _save_protocol_parent_id(self, protocol_player_id: str, parent_id: str) -> None:
1473        """Save the parent ID for a protocol player for persistence across restarts."""
1474        # Only save if the player config still exists to avoid creating partial entries
1475        if not self.mass.config.get(f"{CONF_PLAYERS}/{protocol_player_id}"):
1476            return
1477        conf_key = f"{CONF_PLAYERS}/{protocol_player_id}/values/{CONF_PROTOCOL_PARENT_ID}"
1478        self.mass.config.set(conf_key, parent_id)
1479
1480    def _save_underlying_player_id(self, player: Player) -> None:
1481        """
1482        Persist the derived-transport edge of a player to config.
1483
1484        Allows the edge to be resolved (e.g. by the config UI) even while the
1485        player is not registered. Clears a previously persisted edge when the
1486        player is no longer derived (e.g. a bridge client turned web player).
1487        """
1488        # Only save if the player config still exists to avoid creating partial entries
1489        if not self.mass.config.get(f"{CONF_PLAYERS}/{player.player_id}"):
1490            return
1491        conf_key = f"{CONF_PLAYERS}/{player.player_id}/values/{CONF_UNDERLYING_PLAYER_ID}"
1492        if player.underlying_player_id:
1493            self.mass.config.set(conf_key, player.underlying_player_id)
1494        elif self.mass.config.get(conf_key) is not None:
1495            self.mass.config.set(conf_key, None)
1496
1497    def _get_cached_protocol_parent_id(self, protocol_player_id: str) -> str | None:
1498        """Get cached parent ID for a protocol player from config."""
1499        conf_key = f"{CONF_PLAYERS}/{protocol_player_id}/values/{CONF_PROTOCOL_PARENT_ID}"
1500        result = self.mass.config.get(conf_key, None)
1501        return str(result) if result else None
1502
1503    def _clear_protocol_parent_id(self, protocol_player_id: str) -> None:
1504        """Clear the cached parent ID for a protocol player."""
1505        # Only clear if the player config still exists to avoid creating partial entries
1506        if not self.mass.config.get(f"{CONF_PLAYERS}/{protocol_player_id}"):
1507            return
1508        conf_key = f"{CONF_PLAYERS}/{protocol_player_id}/values/{CONF_PROTOCOL_PARENT_ID}"
1509        self.mass.config.set(conf_key, None)
1510
1511    def _recover_cached_protocol_links(self, native_player: Player) -> None:
1512        """
1513        Recover protocol links from config for disabled/missing protocols.
1514
1515        This ensures that disabled protocols show up in the output_protocols list
1516        so they can be re-enabled by the user. It also handles the case where
1517        protocol players haven't registered yet during startup.
1518        """
1519        # Get currently linked protocol IDs
1520        linked_protocol_ids = {
1521            link.output_protocol_id for link in native_player.linked_output_protocols
1522        }
1523
1524        # Get cached protocol IDs from config (includes protocols that were explicitly linked)
1525        cached_protocol_ids = self._get_cached_protocol_ids(native_player.player_id)
1526
1527        # Also check all protocol players that have protocol_parent_id pointing to this player
1528        # (this handles disabled protocols that may not be in linked_protocol_ids)
1529        all_player_configs = self.mass.config.get(CONF_PLAYERS, {})
1530        for protocol_id, protocol_config in all_player_configs.items():
1531            # Skip if not a protocol player
1532            if protocol_config.get("player_type") != "protocol":
1533                continue
1534            # Check if this protocol has a parent_id pointing to this native player
1535            protocol_values = protocol_config.get("values", {})
1536            protocol_parent_id = protocol_values.get(CONF_PROTOCOL_PARENT_ID)
1537            if protocol_parent_id == native_player.player_id:
1538                if protocol_id not in cached_protocol_ids:
1539                    cached_protocol_ids.append(protocol_id)
1540
1541        if not cached_protocol_ids:
1542            return
1543
1544        # Add link entries for any cached protocols that aren't currently linked
1545        updated_protocols = list(native_player.linked_output_protocols)
1546        for protocol_id in cached_protocol_ids:
1547            if protocol_id in linked_protocol_ids:
1548                continue  # Already linked
1549
1550            # Get protocol player config to determine the protocol domain
1551            protocol_config = self.mass.config.get(f"{CONF_PLAYERS}/{protocol_id}")
1552            if not protocol_config:
1553                continue
1554
1555            # Determine protocol domain from provider
1556            protocol_provider: str = protocol_config.get("provider")
1557            if not protocol_provider:
1558                continue
1559
1560            # Extract domain from provider instance_id (e.g., "airplay--uuid" -> "airplay")
1561            protocol_domain = protocol_provider.split("--", maxsplit=1)[0]
1562
1563            # Skip if parent already has a link from this domain
1564            existing_domains = {link.protocol_domain for link in updated_protocols}
1565            if protocol_domain in existing_domains:
1566                continue
1567
1568            # Get priority for this protocol
1569            priority = PROTOCOL_PRIORITY.get(protocol_domain, 100)
1570
1571            # Resolve the derived-transport edge from the live player when
1572            # registered, else from the persisted edge in config
1573            protocol_player = self.get_player(protocol_id)
1574            derived_from = (
1575                protocol_player.underlying_player_id
1576                if protocol_player
1577                else protocol_config.get("values", {}).get(CONF_UNDERLYING_PLAYER_ID)
1578            )
1579            if derived_from == native_player.player_id:
1580                derived_from = "native"
1581
1582            updated_protocols.append(
1583                LinkedOutputProtocol(
1584                    output_protocol_id=protocol_id,
1585                    protocol_domain=protocol_domain,
1586                    priority=priority,
1587                    derived_from=derived_from,
1588                )
1589            )
1590            self.logger.debug(
1591                "Recovered cached protocol link %s -> %s",
1592                native_player.player_id,
1593                protocol_id,
1594            )
1595
1596        if len(updated_protocols) != len(native_player.linked_output_protocols):
1597            native_player.set_linked_output_protocols(updated_protocols)
1598
1599    def _cleanup_protocol_links(self, player: Player) -> None:
1600        """Clean up protocol links when a player is permanently removed."""
1601        if player.state.type == PlayerType.PROTOCOL:
1602            self._unlink_from_protocol_parent(player)
1603            return
1604        self._detach_owned_protocols(player)
1605
1606    def _unlink_from_protocol_parent(self, player: Player) -> None:
1607        """Release a protocol player from the parent it is attached to."""
1608        if parent_id := player.protocol_parent_id:
1609            if parent_player := self.get_player(parent_id):
1610                # Use permanent=True to also remove from cached protocol IDs
1611                self._remove_protocol_link(parent_player, player.player_id, permanent=True)
1612                if (
1613                    parent_player.provider.domain == "universal_player"
1614                    and len(parent_player.linked_output_protocols) == 0
1615                ):
1616                    # No protocols left - the universal player has nothing to play
1617                    # on. Its config is deliberately kept: the player id is opaque
1618                    # and cannot be recreated, so deleting it here would orphan the
1619                    # entities API consumers bound to it. Only an explicit removal
1620                    # by the user deletes a universal player for good.
1621                    self.logger.info(
1622                        "Universal player %s has no protocols left",
1623                        parent_id,
1624                    )
1625                    self.mass.create_task(self.mass.players.unregister(parent_id, permanent=False))
1626                else:
1627                    parent_player.refresh_state()
1628            else:
1629                # Parent not registered yet — still purge the cached id
1630                self._remove_protocol_id_from_cache(parent_id, player.player_id)
1631
1632    def _detach_owned_protocols(self, player: Player) -> None:
1633        """Detach the protocol players a parent owns so they can find a new parent."""
1634        # collect the ids from both the active links and the cached state, since
1635        # disabled/inactive protocols may only exist in the cached parent data
1636        all_protocol_ids = set(self._get_known_protocol_ids(player))
1637        for protocol_id in all_protocol_ids:
1638            if protocol_player := self.get_player(protocol_id):
1639                # Protocol player is available: clear parent and schedule re-evaluation
1640                # so it can be matched to a new parent or a new universal player
1641                self.logger.debug(
1642                    "Player %s no longer owns protocol %s - scheduling evaluation",
1643                    player.player_id,
1644                    protocol_id,
1645                )
1646                self._detach_protocol_child(protocol_player)
1647            else:
1648                # Clear cached parent ID in config so protocol won't try to
1649                # restore a link to its former parent on next restart
1650                self._clear_protocol_parent_id(protocol_id)
1651                # Protocol player is not registered yet — it may still be
1652                # mid-discovery (e.g., DLNA connecting via SSDP). Don't delete
1653                # its config as that would cause a KeyError when it finishes
1654                # registering. Stale configs are harmless and get cleaned up
1655                # naturally on subsequent restarts.
1656                self.logger.debug(
1657                    "Player %s no longer owns protocol %s - not registered, skipping cleanup",
1658                    player.player_id,
1659                    protocol_id,
1660                )
1661
1662    def _cleanup_player_type_transition(self, existing: Player, *, becomes_protocol: bool) -> None:
1663        """
1664        Release the protocol topology a player owned before its type changed.
1665
1666        :param existing: The registered player instance for the changed player.
1667        :param becomes_protocol: True if the player moves into the protocol role,
1668            False if it leaves it.
1669        """
1670        if not becomes_protocol:
1671            # a provider may announce the new type with the live parent link already
1672            # dropped, so fall back to the persisted one to still reach the parent
1673            parent_id = existing.protocol_parent_id or self._get_cached_protocol_parent_id(
1674                existing.player_id
1675            )
1676            if not parent_id:
1677                return
1678            parent = self.get_player(parent_id)
1679            if parent is not None and parent.provider.domain == "universal_player":
1680                # drop only the active edge and leave the rest to the link evaluation,
1681                # which replaces the wrapper with this player: a leftover edge makes it
1682                # hand the player over to itself, which it refuses, abandoning the swap
1683                self._remove_protocol_link(parent, existing.player_id)
1684                return
1685            existing.set_protocol_parent_id(parent_id)
1686            # unlink at the parent and drop the persisted parent id, which would
1687            # otherwise heal the player's type back to protocol
1688            self._unlink_from_protocol_parent(existing)
1689            # a player leaving the protocol role has no parent, also when that parent
1690            # is not registered (anymore) and only the cached link could be cleaned up
1691            existing.set_protocol_parent_id(None)
1692            return
1693        # the player becomes a child itself: detach the protocol players it owned so they
1694        # can find a new parent, then give up their ownership in its (kept) config - the
1695        # reverse of the removal path, which drops the ownership before the detach
1696        protocol_ids = set(self._get_known_protocol_ids(existing))
1697        self._detach_owned_protocols(existing)
1698        self._remove_protocol_ids_from_parent(existing, protocol_ids)
1699
1700    def _detach_protocol_children(self, parent_id: str) -> None:
1701        """
1702        Detach the registered protocol players of a parent player that is going away.
1703
1704        Covers the removal paths that don't unregister the parent first (e.g. its
1705        provider is unloaded), where the parent is not around anymore to enumerate
1706        its protocol players.
1707
1708        :param parent_id: Player id of the parent that is being removed.
1709        """
1710        for protocol_player in list(self._players.values()):
1711            if protocol_player.state.type != PlayerType.PROTOCOL:
1712                continue
1713            # a protocol player waiting for a parent that never registered only has
1714            # the link in its config, so fall back to the cached parent
1715            linked_parent_id = protocol_player.protocol_parent_id or (
1716                self._get_cached_protocol_parent_id(protocol_player.player_id)
1717            )
1718            if linked_parent_id != parent_id:
1719                continue
1720            self.logger.debug(
1721                "Player %s removed - scheduling evaluation for protocol %s",
1722                parent_id,
1723                protocol_player.player_id,
1724            )
1725            self._detach_protocol_child(protocol_player)
1726
1727    def _detach_protocol_child(self, protocol_player: Player) -> None:
1728        """Clear a protocol player's parent link and schedule a fresh evaluation."""
1729        self._clear_protocol_parent_id(protocol_player.player_id)
1730        protocol_player.set_protocol_parent_id(None)
1731        protocol_player.refresh_state()
1732        self._schedule_protocol_evaluation(protocol_player)
1733
1734    def _identifiers_match(
1735        self, player_a: Player, player_b: Player, protocol_domain: str = ""
1736    ) -> bool:
1737        """
1738        Check if identifiers match between two players.
1739
1740        Matching is done by comparing connection identifiers (MAC, serial, UUID).
1741        As a last resort, IP address is used when at least one player has a
1742        locally-administered MAC, indicating the device uses MAC randomization
1743        and ARP could not resolve the real hardware address.
1744
1745        Invalid identifiers (e.g., 00:00:00:00:00:00 MAC addresses) are filtered out
1746        to prevent false matches between unrelated devices.
1747        """
1748        identifiers_a = player_a.device_info.identifiers
1749        identifiers_b = player_b.device_info.identifiers
1750
1751        # Check identifiers in order of reliability
1752        # MAC_ADDRESS > SERIAL_NUMBER > UUID > CAST_UUID > AIRPLAY_ID
1753        for conn_type in (
1754            IdentifierType.MAC_ADDRESS,
1755            IdentifierType.SERIAL_NUMBER,
1756            IdentifierType.UUID,
1757            IdentifierType.CAST_UUID,
1758            IdentifierType.AIRPLAY_ID,
1759        ):
1760            val_a = identifiers_a.get(conn_type)
1761            val_b = identifiers_b.get(conn_type)
1762
1763            if not val_a or not val_b:
1764                continue
1765
1766            # Filter out invalid MAC addresses (00:00:00:00:00:00, ff:ff:ff:ff:ff:ff)
1767            if conn_type == IdentifierType.MAC_ADDRESS:
1768                if not is_valid_mac_address(val_a) or not is_valid_mac_address(val_b):
1769                    self.logger.log(
1770                        VERBOSE_LOG_LEVEL,
1771                        "Skipping invalid MAC address for matching: %s=%s, %s=%s",
1772                        player_a.display_name,
1773                        val_a,
1774                        player_b.display_name,
1775                        val_b,
1776                    )
1777                    continue
1778
1779            # Normalize values for comparison
1780            if conn_type == IdentifierType.MAC_ADDRESS:
1781                # Use MAC normalization that handles locally-administered bit differences
1782                # Some protocols (like AirPlay) report a locally-administered MAC variant
1783                # where bit 1 of the first octet is set (e.g., 54:78:... vs 56:78:...)
1784                val_a_norm = normalize_mac_for_matching(val_a)
1785                val_b_norm = normalize_mac_for_matching(val_b)
1786
1787                # Direct match on current MAC
1788                if val_a_norm == val_b_norm:
1789                    return True
1790
1791                # Multi-MAC matching: also check original reported MACs.
1792                # Devices with multiple interfaces (WiFi + Ethernet) may have ARP
1793                # resolve one MAC while the protocol reports a different one.
1794                macs_a = {val_a_norm}
1795                macs_b = {val_b_norm}
1796                reported_a = player_a.extra_data.get("reported_mac")
1797                reported_b = player_b.extra_data.get("reported_mac")
1798                if reported_a and is_valid_mac_address(reported_a):
1799                    macs_a.add(normalize_mac_for_matching(reported_a))
1800                if reported_b and is_valid_mac_address(reported_b):
1801                    macs_b.add(normalize_mac_for_matching(reported_b))
1802                if macs_a & macs_b:
1803                    return True
1804
1805                # No MAC match - continue to next identifier type
1806                continue
1807
1808            val_a_norm = val_a.lower().replace(":", "").replace("-", "")
1809            val_b_norm = val_b.lower().replace(":", "").replace("-", "")
1810
1811            # Direct match
1812            if val_a_norm == val_b_norm:
1813                return True
1814
1815            # Special case: Sonos UUID matching with DLNA _MR suffix
1816            # Sonos uses RINCON_xxx, DLNA uses RINCON_xxx_MR for Media Renderer
1817            if conn_type == IdentifierType.UUID:
1818                if val_b_norm.endswith("_mr") and val_b_norm[:-3] == val_a_norm:
1819                    return True
1820                if val_a_norm.endswith("_mr") and val_a_norm[:-3] == val_b_norm:
1821                    return True
1822
1823        # Last resort: IP-based matching.
1824        # Two players on the same IP are very likely the same physical device.
1825        # This handles two cases:
1826        # 1. MAC randomization: at least one player has no real MAC (LA or missing),
1827        #    so ARP couldn't resolve a usable address.
1828        # 2. Different MACs per protocol: some devices (e.g., Yamaha MusicCast) report
1829        #    different valid globally-unique MACs per protocol (DLNA vs AirPlay differ
1830        #    by 1 in the last octet). IP matching is safe here because two different
1831        #    devices on a LAN cannot share the same IP simultaneously.
1832        #    To avoid false positives between unrelated native players, this path
1833        #    requires at least one player to be a protocol or universal player.
1834        ip_a = identifiers_a.get(IdentifierType.IP_ADDRESS)
1835        ip_b = identifiers_b.get(IdentifierType.IP_ADDRESS)
1836        if ip_a and ip_b and ip_a == ip_b:
1837            mac_a = identifiers_a.get(IdentifierType.MAC_ADDRESS)
1838            mac_b = identifiers_b.get(IdentifierType.MAC_ADDRESS)
1839            a_is_real = (
1840                mac_a is not None
1841                and is_valid_mac_address(mac_a)
1842                and not is_locally_administered_mac(mac_a)
1843            )
1844            b_is_real = (
1845                mac_b is not None
1846                and is_valid_mac_address(mac_b)
1847                and not is_locally_administered_mac(mac_b)
1848            )
1849            # Case 1: at least one player has no real hardware MAC
1850            if not (a_is_real and b_is_real):
1851                return True
1852            # Case 2: both have real MACs but at least one is a protocol/universal player
1853            a_is_protocol = (
1854                player_a.type == PlayerType.PROTOCOL
1855                or player_a.provider.domain == "universal_player"
1856            )
1857            b_is_protocol = (
1858                player_b.type == PlayerType.PROTOCOL
1859                or player_b.provider.domain == "universal_player"
1860            )
1861            if a_is_protocol or b_is_protocol:
1862                return True
1863
1864        return False
1865
1866    def _select_best_output_protocol(self, player: Player) -> tuple[Player, OutputProtocol | None]:
1867        """
1868        Select the best available output protocol for a player.
1869
1870        Selection priority:
1871        1. Output protocol that is currently grouped/synced with other players.
1872        2. User's preferred output protocol (from player settings).
1873        3. Native playback (if player supports PLAY_MEDIA).
1874        4. The player's declared default output protocol domain, if available.
1875        5. Best available protocol by priority.
1876
1877        Returns tuple of (target_player, output_protocol).
1878        output_protocol is None when using native playback.
1879        """
1880        self.logger.log(
1881            VERBOSE_LOG_LEVEL,
1882            "Selecting output protocol for %s",
1883            player.state.name,
1884        )
1885
1886        # 1. Check if any output protocol is currently grouped
1887        for linked in player.linked_output_protocols:
1888            if protocol_player := self.get_player(linked.output_protocol_id):
1889                if protocol_player.available_for_playback and self._is_protocol_grouped(
1890                    protocol_player
1891                ):
1892                    self.logger.log(
1893                        VERBOSE_LOG_LEVEL,
1894                        "Selected protocol for %s: %s (grouped)",
1895                        player.state.name,
1896                        protocol_player.state.name,
1897                    )
1898                    return protocol_player, player.get_linked_protocol(linked.output_protocol_id)
1899
1900        # 2. Check for user's preferred output protocol.
1901        # The value is only stored while it differs from the entry's default: "native" when a
1902        # native output is available, otherwise "auto". A player without a native output (e.g. a
1903        # LinkPlay shell) therefore has no stored preference by default and gets its default
1904        # output domain applied in step 4.
1905        preferred = self.mass.config.get_raw_player_config_value(
1906            player.player_id, CONF_PREFERRED_OUTPUT_PROTOCOL
1907        )
1908        if preferred and preferred != "auto":
1909            if preferred == "native":
1910                if PlayerFeature.PLAY_MEDIA in player.supported_features:
1911                    self.logger.log(
1912                        VERBOSE_LOG_LEVEL,
1913                        "Selected protocol for %s: native (user preference)",
1914                        player.state.name,
1915                    )
1916                    return player, None
1917            else:
1918                for linked in player.linked_output_protocols:
1919                    if linked.output_protocol_id == preferred:
1920                        if protocol_player := self.get_player(linked.output_protocol_id):
1921                            if protocol_player.available_for_playback:
1922                                self.logger.log(
1923                                    VERBOSE_LOG_LEVEL,
1924                                    "Selected protocol for %s: %s (user preference)",
1925                                    player.state.name,
1926                                    protocol_player.state.name,
1927                                )
1928                                return protocol_player, player.get_linked_protocol(
1929                                    linked.output_protocol_id
1930                                )
1931                        break
1932
1933        # 3. Use native playback if available
1934        if PlayerFeature.PLAY_MEDIA in player.supported_features:
1935            self.logger.log(
1936                VERBOSE_LOG_LEVEL, "Selected protocol for %s: native", player.state.name
1937            )
1938            return player, None
1939
1940        # 4. Use the player's preferred default protocol domain, if it declares one and a
1941        # matching linked protocol is available (e.g. a LinkPlay shell prefers DLNA). This
1942        # never influences grouping; it only steers the default output for playback. "Auto"
1943        # is the entry default here, so it consistently resolves to this domain default.
1944        if default_domain := player.default_output_protocol_domain:
1945            for linked in sorted(player.linked_output_protocols, key=lambda x: x.priority):
1946                if linked.protocol_domain != default_domain:
1947                    continue
1948                if (protocol_player := self.get_player(linked.output_protocol_id)) and (
1949                    protocol_player.available_for_playback
1950                ):
1951                    self.logger.log(
1952                        VERBOSE_LOG_LEVEL,
1953                        "Selected protocol for %s: %s (default domain %s)",
1954                        player.state.name,
1955                        protocol_player.state.name,
1956                        default_domain,
1957                    )
1958                    return protocol_player, player.get_linked_protocol(linked.output_protocol_id)
1959
1960        # 5. Fall back to best protocol by priority
1961        for linked in sorted(player.linked_output_protocols, key=lambda x: x.priority):
1962            if protocol_player := self.get_player(linked.output_protocol_id):
1963                if protocol_player.available_for_playback:
1964                    self.logger.log(
1965                        VERBOSE_LOG_LEVEL,
1966                        "Selected protocol for %s: %s (priority-based)",
1967                        player.state.name,
1968                        protocol_player.state.name,
1969                    )
1970                    return protocol_player, player.get_linked_protocol(linked.output_protocol_id)
1971
1972        raise PlayerCommandFailed(f"Player {player.state.name} has no available output protocols")
1973
1974    def _get_control_target(
1975        self,
1976        player: Player,
1977        required_feature: PlayerFeature,
1978        require_active: bool = False,
1979    ) -> Player | None:
1980        """
1981        Get the best player(protocol) to send audio-path commands to.
1982
1983        Resolves commands that travel with the audio (enqueue, pause, announcements),
1984        so the output that renders the audio outranks the native player. Volume and
1985        mute are control-plane instead and resolve through
1986        :meth:`Player._get_protocol_player_for_feature`, which orders differently.
1987
1988        :param player: The player the command was issued on.
1989        :param required_feature: The feature the resolved target has to support.
1990        :param require_active: Only accept the output that is already rendering,
1991            instead of falling back to an idle one.
1992        """
1993        # If we have an active protocol, use that
1994        if (
1995            player.active_output_protocol
1996            and player.active_output_protocol != "native"
1997            and (protocol_player := self.mass.players.get_player(player.active_output_protocol))
1998            and required_feature in protocol_player.supported_features
1999        ):
2000            return protocol_player
2001
2002        # if the player natively supports the required feature, use that
2003        if (
2004            player.active_output_protocol == "native"
2005            and required_feature in player.supported_features
2006        ):
2007            return player
2008
2009        # If require_active is set, and no active protocol found, return None
2010        if require_active:
2011            return None
2012
2013        # if the player natively supports the required feature, use that
2014        if required_feature in player.supported_features:
2015            return player
2016
2017        # An output the user explicitly picked owns the audio, so a command that has to
2018        # start playback on an idle player follows it rather than the priority below.
2019        # The stored value survives a relink, so it only counts while it still names one
2020        # of this player's own outputs.
2021        preferred = self.mass.config.get_raw_player_config_value(
2022            player.player_id, CONF_PREFERRED_OUTPUT_PROTOCOL
2023        )
2024        if preferred and preferred not in ("auto", "native"):
2025            for linked in player.linked_output_protocols:
2026                if linked.output_protocol_id != preferred:
2027                    continue
2028                if (
2029                    (preferred_player := self.mass.players.get_player(str(preferred)))
2030                    and preferred_player.available_for_playback
2031                    and required_feature in preferred_player.supported_features
2032                ):
2033                    return preferred_player
2034                break
2035
2036        # Otherwise, use the best available linked protocol, ordered by the same
2037        # priority that regular playback selection applies.
2038        for linked in sorted(player.linked_output_protocols, key=lambda x: x.priority):
2039            if (
2040                (protocol_player := self.mass.players.get_player(linked.output_protocol_id))
2041                and protocol_player.available_for_playback
2042                and required_feature in protocol_player.supported_features
2043            ):
2044                return protocol_player
2045
2046        return None
2047
2048    def _is_protocol_grouped(self, protocol_player: Player) -> bool:
2049        """
2050        Check if a protocol player is currently grouped/synced with other players.
2051
2052        Used to prefer protocols that are actively participating in a group,
2053        ensuring consistent playback across grouped players.
2054        """
2055        is_grouped = bool(
2056            protocol_player.state.synced_to
2057            or (
2058                protocol_player.state.group_members and len(protocol_player.state.group_members) > 1
2059            )
2060            or protocol_player.state.active_group
2061        )
2062        if is_grouped:
2063            self.logger.log(
2064                VERBOSE_LOG_LEVEL,
2065                "Protocol player %s is grouped",
2066                protocol_player.state.name,
2067            )
2068        return is_grouped
2069
2070    def _translate_members_to_remove_for_protocols(
2071        self,
2072        parent_player: Player,
2073        player_ids: list[str],
2074        parent_protocol_player: Player | None,
2075        parent_protocol_domain: str | None,
2076    ) -> tuple[list[str], list[str]]:
2077        """
2078        Translate member IDs to remove into protocol and native lists.
2079
2080        :param parent_player: The parent player to remove members from.
2081        :param player_ids: List of visible player IDs to remove.
2082        :param parent_protocol_player: The parent's protocol player if available.
2083        :param parent_protocol_domain: The parent's protocol domain if available.
2084        """
2085        self.logger.debug(
2086            "Translating members to remove for %s: player_ids=%s, parent_protocol_domain=%s",
2087            parent_player.state.name,
2088            player_ids,
2089            parent_protocol_domain,
2090        )
2091        protocol_members: list[str] = []
2092        native_members: list[str] = []
2093
2094        for child_player_id in player_ids:
2095            child_player = self.get_player(child_player_id)
2096            if not child_player:
2097                continue
2098
2099            # Check if this member is in the parent's group via protocol
2100            if parent_protocol_domain and parent_protocol_player:
2101                child_protocol = child_player.get_output_protocol_by_domain(parent_protocol_domain)
2102                if child_protocol and child_protocol.available:
2103                    # For native protocol players, use the child's player_id directly
2104                    child_protocol_id = (
2105                        child_player.player_id
2106                        if child_protocol.is_native
2107                        else child_protocol.output_protocol_id
2108                    )
2109                    if child_protocol_id in parent_protocol_player.group_members:
2110                        self.logger.debug(
2111                            "Translating removal: %s -> protocol %s",
2112                            child_player_id,
2113                            child_protocol_id,
2114                        )
2115                        protocol_members.append(child_protocol_id)
2116                        continue
2117
2118            # Check if child's protocol player is in parent's native group_members
2119            # This handles native protocol players (e.g., native AirPlay player like Apple TV)
2120            # where the parent itself contains protocol player IDs in its group_members
2121            translated = False
2122            for linked in child_player.linked_output_protocols:
2123                if linked.output_protocol_id in parent_player.group_members:
2124                    self.logger.debug(
2125                        "Translating removal (native parent): %s -> protocol %s",
2126                        child_player_id,
2127                        linked.output_protocol_id,
2128                    )
2129                    native_members.append(linked.output_protocol_id)
2130                    translated = True
2131                    break
2132
2133            if not translated:
2134                native_members.append(child_player_id)
2135
2136        return protocol_members, native_members
2137
2138    def _filter_protocol_members(self, member_ids: list[str], protocol_player: Player) -> list[str]:
2139        """Filter member IDs to only include players from the same protocol domain."""
2140        return [
2141            pid
2142            for pid in member_ids
2143            if (p := self.get_player(pid)) and p.provider.domain == protocol_player.provider.domain
2144        ]
2145
2146    def _filter_native_members(self, member_ids: list[str], parent_player: Player) -> list[str]:
2147        """Filter member IDs to only include players compatible with the parent."""
2148        return [
2149            pid
2150            for pid in member_ids
2151            if (p := self.get_player(pid))
2152            and (
2153                p.provider.instance_id == parent_player.provider.instance_id
2154                or pid in parent_player._attr_can_group_with
2155                or p.provider.instance_id in parent_player._attr_can_group_with
2156            )
2157        ]
2158
2159    def _try_child_preferred_protocol(
2160        self,
2161        child_player: Player,
2162        parent_player: Player,
2163    ) -> tuple[str | None, str | None]:
2164        """
2165        Try to use child's preferred output protocol for grouping.
2166
2167        Returns tuple of (child_protocol_id, protocol_domain) or (None, None).
2168        """
2169        child_preferred = self.mass.config.get_raw_player_config_value(
2170            child_player.player_id, CONF_PREFERRED_OUTPUT_PROTOCOL
2171        )
2172        if not child_preferred or child_preferred in {"auto", "native"}:
2173            return None, None
2174
2175        # Find child's preferred protocol, with its current availability
2176        child_protocol = None
2177        for output_protocol in child_player.output_protocols:
2178            if output_protocol.output_protocol_id == child_preferred:
2179                child_protocol = output_protocol
2180                break
2181
2182        if not child_protocol or not child_protocol.available:
2183            return None, None
2184
2185        # Check if parent supports this protocol (including native protocol)
2186        parent_protocol = parent_player.get_output_protocol_by_domain(
2187            child_protocol.protocol_domain
2188        )
2189        if not parent_protocol or not parent_protocol.available:
2190            return None, None
2191
2192        # Check if this protocol supports set_members
2193        protocol_player = parent_player.get_protocol_player(parent_protocol.output_protocol_id)
2194        if (
2195            not protocol_player
2196            or PlayerFeature.SET_MEMBERS not in protocol_player.state.supported_features
2197        ):
2198            return None, None
2199
2200        return child_protocol.output_protocol_id, child_protocol.protocol_domain
2201
2202    def _can_use_native_grouping(
2203        self,
2204        child_player: Player,
2205        parent_player: Player,
2206        parent_supports_native: bool,
2207    ) -> bool:
2208        """Check if child can be grouped with parent using native grouping."""
2209        if not parent_supports_native:
2210            return False
2211        return (
2212            parent_player.is_native_group_compatible(child_player)
2213            or child_player.player_id in parent_player._attr_can_group_with
2214            or child_player.provider.instance_id in parent_player._attr_can_group_with
2215        )
2216
2217    def _try_find_common_protocol(
2218        self, child_player: Player, parent_player: Player
2219    ) -> tuple[OutputProtocol | None, OutputProtocol | None]:
2220        """
2221        Find common protocol that supports set_members.
2222
2223        Returns tuple of (parent_protocol, child_protocol) or (None, None).
2224        """
2225        for parent_output_protocol in parent_player.output_protocols:
2226            if not parent_output_protocol.available:
2227                continue
2228            child_protocol = child_player.get_output_protocol_by_domain(
2229                parent_output_protocol.protocol_domain
2230            )
2231            if not child_protocol or not child_protocol.available:
2232                continue
2233            protocol_player = parent_player.get_protocol_player(
2234                parent_output_protocol.output_protocol_id
2235            )
2236            if protocol_player and PlayerFeature.SET_MEMBERS in protocol_player.supported_features:
2237                return parent_output_protocol, child_protocol
2238        return None, None
2239
2240    def _parent_has_live_native_session(self, parent_player: Player) -> bool:
2241        """
2242        Return True when the parent currently holds a live native playback session.
2243
2244        The active output protocol lingers for a few seconds after stop, so a non-idle
2245        playback state is required to distinguish a real session from a just-stopped one.
2246        """
2247        return parent_player.active_output_protocol == "native" and (
2248            parent_player.state.playback_state in (PlaybackState.PLAYING, PlaybackState.PAUSED)
2249        )
2250
2251    def _order_members_for_native_join(
2252        self,
2253        player_ids: list[str],
2254        parent_player: Player,
2255        parent_supports_native_grouping: bool,
2256    ) -> list[str]:
2257        """
2258        Order members so a live native session can be joined without splitting the group.
2259
2260        When the parent already holds a live native session, children that cannot group
2261        natively are evaluated first: they may force a shared protocol for the whole group,
2262        and processing them before the native-capable children lets those join that same
2263        protocol instead of being stranded in a separate native sub-group. The order is left
2264        untouched when the parent is not playing natively, so fresh-group selection is unchanged.
2265
2266        :param player_ids: The member IDs to be added, in their original order.
2267        :param parent_player: The parent player being joined.
2268        :param parent_supports_native_grouping: Whether the parent can group natively.
2269        """
2270        if not self._parent_has_live_native_session(parent_player):
2271            return player_ids
2272        return sorted(
2273            player_ids,
2274            key=lambda pid: bool(
2275                (child := self.get_player(pid))
2276                and self._can_use_native_grouping(
2277                    child, parent_player, parent_supports_native_grouping
2278                )
2279            ),
2280        )
2281
2282    def _try_join_active_native_session(
2283        self,
2284        child_player: Player,
2285        parent_player: Player,
2286        parent_protocol_domain: str | None,
2287        parent_supports_native_grouping: bool,
2288        native_members: list[str],
2289    ) -> bool:
2290        """
2291        Add the child to native_members if it can join the parent's active native session.
2292
2293        A child's preferred output protocol must only steer protocol selection when the child
2294        initiates its own playback; when it joins a parent that is already playing natively it
2295        should adopt native grouping if compatible, rather than forcing the whole group onto
2296        the child's preferred protocol. Skipped once a protocol has been selected for the group,
2297        so mixed batches stay cohesive on a single protocol.
2298
2299        :param child_player: The player being added to the group.
2300        :param parent_player: The parent player being joined.
2301        :param parent_protocol_domain: The protocol domain already selected for the group, if any.
2302        :param parent_supports_native_grouping: Whether the parent can group natively.
2303        :param native_members: The native members list to append to when the child joins.
2304        """
2305        if not (
2306            self._parent_has_live_native_session(parent_player)
2307            and not parent_protocol_domain
2308            and self._can_use_native_grouping(
2309                child_player, parent_player, parent_supports_native_grouping
2310            )
2311        ):
2312            return False
2313        native_members.append(child_player.player_id)
2314        self.logger.log(
2315            VERBOSE_LOG_LEVEL,
2316            "Joining parent's active native session for %s",
2317            child_player.state.name,
2318        )
2319        return True
2320
2321    def _translate_native_members_to_protocol(
2322        self, parent_player: Player, protocol_domain: str, member_ids: list[str]
2323    ) -> list[str]:
2324        """
2325        Translate natively grouped members onto the protocol domain the parent plays through.
2326
2327        Members that do not have that protocol cannot follow the parent at all and are
2328        dropped with a warning instead.
2329
2330        :param parent_player: The parent player the members are grouped with.
2331        :param protocol_domain: The protocol domain selected for the group.
2332        :param member_ids: The member IDs that were selected for native grouping.
2333        """
2334        translated: list[str] = []
2335        for member_id in member_ids:
2336            member_player = self.get_player(member_id)
2337            if not member_player:
2338                continue
2339            # a native group's members may be listed by their protocol player id
2340            if member_player.protocol_parent_id:
2341                member_player = self.get_player(member_player.protocol_parent_id) or member_player
2342            member_protocol = member_player.get_output_protocol_by_domain(protocol_domain)
2343            if not member_protocol or not member_protocol.available:
2344                self.logger.warning(
2345                    "Cannot group %s with %s: the group plays through the %s protocol, "
2346                    "which %s does not support",
2347                    member_player.state.name,
2348                    parent_player.state.name,
2349                    protocol_domain,
2350                    member_player.state.name,
2351                )
2352                continue
2353            # For native protocol players, use the member's player_id directly
2354            translated.append(
2355                member_player.player_id
2356                if member_protocol.is_native
2357                else member_protocol.output_protocol_id
2358            )
2359            self.logger.log(
2360                VERBOSE_LOG_LEVEL,
2361                "Moving %s from native grouping to the %s protocol",
2362                member_player.state.name,
2363                protocol_domain,
2364            )
2365        return translated
2366
2367    def _move_native_members_to_group_protocol(
2368        self,
2369        parent_player: Player,
2370        parent_protocol_player: Player | None,
2371        parent_protocol_domain: str | None,
2372        protocol_members: list[str],
2373        native_members: list[str],
2374    ) -> None:
2375        """
2376        Move the members selected for native grouping onto the protocol the group ended up on.
2377
2378        Does nothing unless the group ends up on one of the parent's protocols while the
2379        parent's native grouping needs the parent's own stream: only then do those members
2380        have no session left to attach to.
2381
2382        :param parent_player: The parent player being joined.
2383        :param parent_protocol_player: The protocol player selected for the group, if any.
2384        :param parent_protocol_domain: The protocol domain selected for the group, if any.
2385        :param protocol_members: The protocol member list the translated IDs are added to.
2386        :param native_members: The native member IDs, emptied when they are moved over.
2387        """
2388        if not (
2389            native_members
2390            and parent_protocol_domain
2391            and parent_protocol_player
2392            and parent_protocol_player.player_id != parent_player.player_id
2393            and parent_player.native_grouping_requires_own_stream
2394        ):
2395            return
2396        protocol_members.extend(
2397            self._translate_native_members_to_protocol(
2398                parent_player, parent_protocol_domain, native_members
2399            )
2400        )
2401        native_members.clear()
2402
2403    def _migrate_stranded_native_members(
2404        self,
2405        parent_player: Player,
2406        parent_protocol_player: Player,
2407        protocol_members: list[str],
2408    ) -> list[str]:
2409        """
2410        Move the native members that a switch to the given protocol strands onto that protocol.
2411
2412        Returns the member IDs that are still attached to the parent's own stream, so the
2413        caller can release them from it. Empty unless the parent renders that stream itself
2414        while its native grouping attaches the members to exactly that stream: only then are
2415        they left without anything to play.
2416
2417        :param parent_player: The parent player that is about to switch protocol.
2418        :param parent_protocol_player: The protocol player the parent will render through.
2419        :param protocol_members: The protocol member list the translated IDs are added to.
2420        """
2421        if parent_protocol_player.player_id == parent_player.player_id:
2422            return []
2423        if not parent_player.native_grouping_requires_own_stream:
2424            return []
2425        if parent_player.active_output_protocol not in (None, "native"):
2426            return []
2427        if parent_player.state.playback_state not in (PlaybackState.PLAYING, PlaybackState.PAUSED):
2428            return []
2429        stranded = [
2430            member_id
2431            for member_id in parent_player.group_members
2432            if member_id != parent_player.player_id
2433        ]
2434        for protocol_id in self._translate_native_members_to_protocol(
2435            parent_player, parent_protocol_player.provider.domain, stranded
2436        ):
2437            if protocol_id not in protocol_members:
2438                protocol_members.append(protocol_id)
2439        return stranded
2440
2441    async def _stop_native_session(
2442        self,
2443        parent_player: Player,
2444        parent_protocol_player: Player,
2445        stranded_native_members: list[str],
2446    ) -> None:
2447        """
2448        Release the given members from the parent's own stream and stop it.
2449
2450        :param parent_player: The parent player whose native session is handed over.
2451        :param parent_protocol_player: The protocol player taking the output over.
2452        :param stranded_native_members: The members to release, already migrated.
2453        """
2454        self.logger.debug(
2455            "Stopping the native session of %s before switching to %s, migrated members: %s",
2456            parent_player.state.name,
2457            parent_protocol_player.state.name,
2458            stranded_native_members,
2459        )
2460        # The members already joined the protocol group, so the native session only has to
2461        # release them and stop. Releasing them first also clears the native group, which
2462        # keeps a later native playback command from resurrecting it. Both calls take the
2463        # provider's own lock, so they must run one after the other.
2464        await parent_player.set_members(player_ids_to_remove=stranded_native_members)
2465        await parent_player.stop()
2466
2467    def _translate_members_for_protocols(
2468        self,
2469        parent_player: Player,
2470        player_ids: list[str],
2471        parent_protocol_player: Player | None,
2472        parent_protocol_domain: str | None,
2473    ) -> tuple[list[str], list[str], Player | None, str | None]:
2474        """
2475        Translate member IDs to protocol or native IDs.
2476
2477        The grouping method is picked per member, see _select_grouping_for_member.
2478
2479        Returns tuple of (protocol_members, native_members, protocol_player, protocol_domain).
2480        """
2481        protocol_members: list[str] = []
2482        native_members: list[str] = []
2483        parent_supports_native_grouping = (
2484            PlayerFeature.SET_MEMBERS in parent_player.supported_features
2485        )
2486        player_ids = self._order_members_for_native_join(
2487            player_ids, parent_player, parent_supports_native_grouping
2488        )
2489
2490        self.logger.log(
2491            VERBOSE_LOG_LEVEL,
2492            "Translating members for %s: parent_supports_native=%s, parent_protocol=%s (%s)",
2493            parent_player.state.name,
2494            parent_supports_native_grouping,
2495            parent_protocol_player.state.name if parent_protocol_player else "none",
2496            parent_protocol_domain or "none",
2497        )
2498
2499        for child_player_id in player_ids:
2500            child_player = self.get_player(child_player_id)
2501            if not child_player:
2502                continue
2503
2504            self.logger.log(
2505                VERBOSE_LOG_LEVEL,
2506                "Processing child %s (type=%s, protocols=%s)",
2507                child_player.state.name,
2508                child_player.state.type,
2509                [p.protocol_domain for p in child_player.output_protocols],
2510            )
2511
2512            parent_protocol_player, parent_protocol_domain = self._select_grouping_for_member(
2513                child_player,
2514                parent_player,
2515                parent_protocol_player,
2516                parent_protocol_domain,
2517                parent_supports_native_grouping,
2518                protocol_members,
2519                native_members,
2520            )
2521
2522        # Post-pass: the protocol selected for the group is only known once every child has
2523        # been processed, so the members picked for native grouping are corrected here.
2524        self._move_native_members_to_group_protocol(
2525            parent_player,
2526            parent_protocol_player,
2527            parent_protocol_domain,
2528            protocol_members,
2529            native_members,
2530        )
2531
2532        return protocol_members, native_members, parent_protocol_player, parent_protocol_domain
2533
2534    def _select_grouping_for_member(
2535        self,
2536        child_player: Player,
2537        parent_player: Player,
2538        parent_protocol_player: Player | None,
2539        parent_protocol_domain: str | None,
2540        parent_supports_native_grouping: bool,
2541        protocol_members: list[str],
2542        native_members: list[str],
2543    ) -> tuple[Player | None, str | None]:
2544        """
2545        Pick the grouping method for a single member and add it to the matching member list.
2546
2547        Selection priority when grouping:
2548        0. If the parent is already playing natively and the child can be grouped
2549           natively, join that native session (a child joining an existing group must
2550           not force the whole group onto its own preferred output protocol)
2551        1. Try child's preferred output protocol (from player settings)
2552        2. Try parent's active output protocol (if any and child supports it)
2553        3. Try native grouping (if parent and child are compatible)
2554        4. Search for common protocol that supports set_members
2555        5. Log warning if no option works
2556
2557        Returns the protocol player/domain the group is on, which the picked method may have
2558        changed.
2559
2560        :param child_player: The player being added to the group.
2561        :param parent_player: The parent player being joined.
2562        :param parent_protocol_player: The protocol player selected for the group so far, if any.
2563        :param parent_protocol_domain: The protocol domain selected for the group so far, if any.
2564        :param parent_supports_native_grouping: Whether the parent can group natively.
2565        :param protocol_members: The protocol member list to append to.
2566        :param native_members: The native member list to append to.
2567        """
2568        # Priority 0: The parent is already playing natively and the child can join
2569        # that native session directly - adopt it before considering the child's own
2570        # preferred output protocol.
2571        if self._try_join_active_native_session(
2572            child_player,
2573            parent_player,
2574            parent_protocol_domain,
2575            parent_supports_native_grouping,
2576            native_members,
2577        ):
2578            return parent_protocol_player, parent_protocol_domain
2579
2580        # Priority 0.5: a player that runs its own multiroom (e.g. a LinkPlay control shell)
2581        # keeps grouping on its native path rather than routing it through a linked protocol
2582        # that is merely its preferred playback output. Native compatibility still decides
2583        # whether this is possible, so an incompatible/cross-backend pair falls through.
2584        if child_player.prefer_native_grouping and self._can_use_native_grouping(
2585            child_player, parent_player, parent_supports_native_grouping
2586        ):
2587            native_members.append(child_player.player_id)
2588            self.logger.log(
2589                VERBOSE_LOG_LEVEL,
2590                "Using native grouping (preferred) for %s",
2591                child_player.state.name,
2592            )
2593            return parent_protocol_player, parent_protocol_domain
2594
2595        # Priority 1: the child's preferred output protocol
2596        grouped, parent_protocol_player, parent_protocol_domain = (
2597            self._try_group_via_preferred_protocol(
2598                child_player,
2599                parent_player,
2600                parent_protocol_player,
2601                parent_protocol_domain,
2602                protocol_members,
2603            )
2604        )
2605        if grouped:
2606            return parent_protocol_player, parent_protocol_domain
2607
2608        # Priority 2: the protocol the group is already on
2609        grouped, parent_protocol_player, parent_protocol_domain = (
2610            self._try_group_via_active_protocol(
2611                child_player,
2612                parent_protocol_player,
2613                parent_protocol_domain,
2614                protocol_members,
2615            )
2616        )
2617        if grouped:
2618            return parent_protocol_player, parent_protocol_domain
2619
2620        # Priority 3: native grouping
2621        if self._can_use_native_grouping(
2622            child_player, parent_player, parent_supports_native_grouping
2623        ):
2624            native_members.append(child_player.player_id)
2625            self.logger.log(
2626                VERBOSE_LOG_LEVEL,
2627                "Using native grouping for %s",
2628                child_player.state.name,
2629            )
2630            return parent_protocol_player, parent_protocol_domain
2631
2632        # Priority 4: a protocol both players share that supports set_members
2633        grouped, parent_protocol_player, parent_protocol_domain = (
2634            self._try_group_via_common_protocol(
2635                child_player,
2636                parent_player,
2637                parent_protocol_player,
2638                parent_protocol_domain,
2639                protocol_members,
2640            )
2641        )
2642        if grouped:
2643            return parent_protocol_player, parent_protocol_domain
2644
2645        # Priority 5: no option worked
2646        self.logger.warning(
2647            "Cannot group %s with %s: no compatible grouping method found "
2648            "(tried: child preferred protocol, parent active protocol, "
2649            "native grouping, common protocols)",
2650            child_player.state.name,
2651            parent_player.state.name,
2652        )
2653        return parent_protocol_player, parent_protocol_domain
2654
2655    def _try_group_via_preferred_protocol(
2656        self,
2657        child_player: Player,
2658        parent_player: Player,
2659        parent_protocol_player: Player | None,
2660        parent_protocol_domain: str | None,
2661        protocol_members: list[str],
2662    ) -> tuple[bool, Player | None, str | None]:
2663        """
2664        Try to group the child through the output protocol it prefers in its player settings.
2665
2666        Only used when the group is not on a protocol yet or is already on that same protocol.
2667        Returns whether the child was grouped, together with the protocol player/domain the
2668        group is on: the child's preferred protocol may become the group's protocol.
2669
2670        :param child_player: The player being added to the group.
2671        :param parent_player: The parent player being joined.
2672        :param parent_protocol_player: The protocol player selected for the group so far, if any.
2673        :param parent_protocol_domain: The protocol domain selected for the group so far, if any.
2674        :param protocol_members: The protocol member list to append to.
2675        """
2676        child_protocol_id, protocol_domain = self._try_child_preferred_protocol(
2677            child_player, parent_player
2678        )
2679        if not (
2680            child_protocol_id
2681            and protocol_domain
2682            and (not parent_protocol_domain or protocol_domain == parent_protocol_domain)
2683        ):
2684            return False, parent_protocol_player, parent_protocol_domain
2685
2686        if not parent_protocol_player or parent_protocol_domain != protocol_domain:
2687            parent_protocol = parent_player.get_output_protocol_by_domain(protocol_domain)
2688            if parent_protocol:
2689                parent_protocol_player = parent_player.get_protocol_player(
2690                    parent_protocol.output_protocol_id
2691                )
2692                parent_protocol_domain = protocol_domain
2693        protocol_members.append(child_protocol_id)
2694        self.logger.log(
2695            VERBOSE_LOG_LEVEL,
2696            "Using child's preferred protocol %s for %s",
2697            protocol_domain,
2698            child_player.state.name,
2699        )
2700        return True, parent_protocol_player, parent_protocol_domain
2701
2702    def _try_group_via_active_protocol(
2703        self,
2704        child_player: Player,
2705        parent_protocol_player: Player | None,
2706        parent_protocol_domain: str | None,
2707        protocol_members: list[str],
2708    ) -> tuple[bool, Player | None, str | None]:
2709        """
2710        Try to group the child through the protocol the group is already on.
2711
2712        Returns whether the child was grouped, together with the protocol player/domain the
2713        group is on: the selection is dropped when that protocol cannot group members itself,
2714        so a later grouping method can select another one.
2715
2716        :param child_player: The player being added to the group.
2717        :param parent_protocol_player: The protocol player selected for the group so far, if any.
2718        :param parent_protocol_domain: The protocol domain selected for the group so far, if any.
2719        :param protocol_members: The protocol member list to append to.
2720        """
2721        if not parent_protocol_domain or not parent_protocol_player:
2722            return False, parent_protocol_player, parent_protocol_domain
2723
2724        if PlayerFeature.SET_MEMBERS not in parent_protocol_player.state.supported_features:
2725            self.logger.log(
2726                VERBOSE_LOG_LEVEL,
2727                "Parent's active protocol %s does not support SET_MEMBERS, "
2728                "will search for alternative",
2729                parent_protocol_domain,
2730            )
2731            # Drop the selection so a later grouping method can select a new protocol
2732            return False, None, None
2733
2734        child_protocol = child_player.get_output_protocol_by_domain(parent_protocol_domain)
2735        if not child_protocol or not child_protocol.available:
2736            return False, parent_protocol_player, parent_protocol_domain
2737
2738        # For native protocol players, use the child's player_id directly
2739        # (e.g., a native sendspin web player IS the protocol player)
2740        child_protocol_id = (
2741            child_player.player_id
2742            if child_protocol.is_native
2743            else child_protocol.output_protocol_id
2744        )
2745        protocol_members.append(child_protocol_id)
2746        self.logger.log(
2747            VERBOSE_LOG_LEVEL,
2748            "Using parent's active protocol %s for %s",
2749            parent_protocol_domain,
2750            child_player.state.name,
2751        )
2752        return True, parent_protocol_player, parent_protocol_domain
2753
2754    def _try_group_via_common_protocol(
2755        self,
2756        child_player: Player,
2757        parent_player: Player,
2758        parent_protocol_player: Player | None,
2759        parent_protocol_domain: str | None,
2760        protocol_members: list[str],
2761    ) -> tuple[bool, Player | None, str | None]:
2762        """
2763        Try to group the child through a protocol both players share.
2764
2765        Returns whether the child was grouped, together with the protocol player/domain the
2766        group is on: the shared protocol may become the group's protocol.
2767
2768        :param child_player: The player being added to the group.
2769        :param parent_player: The parent player being joined.
2770        :param parent_protocol_player: The protocol player selected for the group so far, if any.
2771        :param parent_protocol_domain: The protocol domain selected for the group so far, if any.
2772        :param protocol_members: The protocol member list to append to.
2773        """
2774        parent_protocol, child_protocol = self._try_find_common_protocol(
2775            child_player, parent_player
2776        )
2777        if not parent_protocol or not child_protocol:
2778            return False, parent_protocol_player, parent_protocol_domain
2779
2780        if not parent_protocol_player or parent_protocol_domain != parent_protocol.protocol_domain:
2781            parent_protocol_player = parent_player.get_protocol_player(
2782                parent_protocol.output_protocol_id
2783            )
2784            if parent_protocol_player:
2785                parent_protocol_domain = parent_protocol_player.provider.domain
2786        # For native protocol players, use the child's player_id directly
2787        child_protocol_id = (
2788            child_player.player_id
2789            if child_protocol.is_native
2790            else child_protocol.output_protocol_id
2791        )
2792        protocol_members.append(child_protocol_id)
2793        self.logger.log(
2794            VERBOSE_LOG_LEVEL,
2795            "Selected common protocol %s for grouping %s with %s",
2796            parent_protocol.protocol_domain,
2797            child_player.state.name,
2798            parent_player.state.name,
2799        )
2800        return True, parent_protocol_player, parent_protocol_domain
2801
2802    async def _forward_protocol_set_members(
2803        self,
2804        parent_player: Player,
2805        parent_protocol_player: Player,
2806        protocol_members_to_add: list[str],
2807        protocol_members_to_remove: list[str],
2808    ) -> None:
2809        """
2810        Forward protocol members to protocol player's set_members and manage active output protocol.
2811
2812        :param parent_player: The parent player (native/universal).
2813        :param parent_protocol_player: The protocol player to forward commands to.
2814        :param protocol_members_to_add: Protocol player IDs to add.
2815        :param protocol_members_to_remove: Protocol player IDs to remove.
2816        """
2817        filtered_protocol_add = self._filter_protocol_members(
2818            protocol_members_to_add, parent_protocol_player
2819        )
2820        filtered_protocol_remove = self._filter_protocol_members(
2821            protocol_members_to_remove, parent_protocol_player
2822        )
2823        self.logger.debug(
2824            "Protocol grouping on %s: filtered_add=%s, filtered_remove=%s",
2825            parent_protocol_player.state.name,
2826            filtered_protocol_add,
2827            filtered_protocol_remove,
2828        )
2829
2830        if not filtered_protocol_add and not filtered_protocol_remove:
2831            return
2832
2833        # Safety check: verify protocol player supports SET_MEMBERS
2834        if PlayerFeature.SET_MEMBERS not in parent_protocol_player.state.supported_features:
2835            self.logger.error(
2836                "Protocol player %s does not support SET_MEMBERS, cannot perform grouping. "
2837                "This should have been caught earlier in the flow.",
2838                parent_protocol_player.state.name,
2839            )
2840            return
2841
2842        # Members that ride the parent's own stream are stranded by the protocol switch below,
2843        # so they join the protocol group in this very same call and their native session is
2844        # torn down afterwards.
2845        stranded_native_members = (
2846            self._migrate_stranded_native_members(
2847                parent_player, parent_protocol_player, filtered_protocol_add
2848            )
2849            if filtered_protocol_add
2850            else []
2851        )
2852
2853        # This runs before set_members because a member's own stream starts inside that call
2854        # and the provider resolves the member's volume control as it starts: unless its parent
2855        # already points at this protocol, that resolution picks a sibling interface of the same
2856        # device (e.g. its cast side) over the one carrying the audio.
2857        self._activate_protocol_on_added_children(filtered_protocol_add)
2858
2859        self.logger.debug(
2860            "Calling set_members on protocol player %s with add=%s, remove=%s",
2861            parent_protocol_player.state.name,
2862            filtered_protocol_add,
2863            filtered_protocol_remove,
2864        )
2865        await parent_protocol_player.set_members(
2866            player_ids_to_add=filtered_protocol_add or None,
2867            player_ids_to_remove=filtered_protocol_remove or None,
2868        )
2869
2870        if filtered_protocol_add:
2871            await self._activate_group_output_protocol(
2872                parent_player, parent_protocol_player, stranded_native_members
2873            )
2874
2875        self.logger.debug(
2876            "After set_members, protocol player %s state: group_members=%s, synced_to=%s",
2877            parent_protocol_player.state.name,
2878            parent_protocol_player.group_members,
2879            parent_protocol_player.synced_to,
2880        )
2881
2882    def _activate_protocol_on_added_children(self, protocol_member_ids: list[str]) -> None:
2883        """
2884        Point the parent of each given protocol member at the protocol carrying the group audio.
2885
2886        :param protocol_member_ids: The protocol player IDs joining the group.
2887        """
2888        for child_protocol_id in protocol_member_ids:
2889            if not (child_protocol := self.get_player(child_protocol_id)):
2890                continue
2891            if not child_protocol.protocol_parent_id:
2892                continue
2893            if not (child_player := self.get_player(child_protocol.protocol_parent_id)):
2894                continue
2895            if child_player.active_output_protocol == child_protocol_id:
2896                continue
2897            self.logger.debug(
2898                "Setting active output protocol on child %s to %s",
2899                child_player.state.name,
2900                child_protocol_id,
2901            )
2902            child_player.set_active_output_protocol(child_protocol_id)
2903
2904    async def _activate_group_output_protocol(
2905        self,
2906        parent_player: Player,
2907        parent_protocol_player: Player,
2908        stranded_native_members: list[str],
2909    ) -> None:
2910        """
2911        Mark the given protocol as the parent's output and hand the playback over to it.
2912
2913        The handover only runs when the parent is actually switching protocol while it is
2914        rendering; playback is resumed only for a parent that was playing, so adding a member
2915        never starts playback on its own.
2916
2917        :param parent_player: The parent player that just gained protocol members.
2918        :param parent_protocol_player: The protocol player the members joined.
2919        :param stranded_native_members: The members left without a stream by the switch.
2920        """
2921        previous_protocol = parent_player.active_output_protocol
2922        was_playing = parent_player.state.playback_state == PlaybackState.PLAYING
2923        # A paused player still holds its output, so the handover has to run for it too.
2924        was_rendering = was_playing or parent_player.state.playback_state == PlaybackState.PAUSED
2925
2926        # Native protocol: parent_protocol_player is the same as parent_player
2927        is_native_protocol = parent_protocol_player.player_id == parent_player.player_id
2928        already_using_native = previous_protocol in (None, "native")
2929        already_using_this_protocol = previous_protocol == parent_protocol_player.player_id
2930        switching_protocols = not (
2931            (is_native_protocol and already_using_native) or already_using_this_protocol
2932        )
2933
2934        self.logger.debug(
2935            "Protocol grouping: is_native=%s, already_native=%s, already_this=%s, "
2936            "switching=%s, was_rendering=%s",
2937            is_native_protocol,
2938            already_using_native,
2939            already_using_this_protocol,
2940            switching_protocols,
2941            was_rendering,
2942        )
2943
2944        if not (is_native_protocol and already_using_native):
2945            parent_player.set_active_output_protocol(parent_protocol_player.player_id)
2946
2947        if not (was_rendering and switching_protocols):
2948            return
2949
2950        self.logger.info(
2951            "Handing the output of %s over to the %s protocol%s",
2952            parent_player.state.name,
2953            parent_protocol_player.provider.domain,
2954            " and resuming playback" if was_playing else "",
2955        )
2956        if stranded_native_members:
2957            await self._stop_native_session(
2958                parent_player, parent_protocol_player, stranded_native_members
2959            )
2960        old_parent_members = await self._stop_previous_protocol(
2961            parent_player, parent_protocol_player, previous_protocol
2962        )
2963        if was_playing:
2964            await self.mass.players.cmd_resume(parent_player.player_id)
2965        if old_parent_members:
2966            self.logger.debug(
2967                "Re-adding migrated members %s to %s on new protocol",
2968                old_parent_members,
2969                parent_player.state.name,
2970            )
2971            # Use internal handler because we are already inside a
2972            # _handle_set_members call chain that holds the play lock.
2973            await self.mass.players._handle_set_members(
2974                parent_player,
2975                player_ids_to_add=old_parent_members,
2976            )
2977
2978    async def _stop_previous_protocol(
2979        self,
2980        parent_player: Player,
2981        parent_protocol_player: Player,
2982        previous_protocol: str | None,
2983    ) -> list[str]:
2984        """
2985        Stop the protocol player the parent was rendering through and return its members.
2986
2987        The returned IDs are parent player IDs, so the caller can re-add them to the group
2988        once the new protocol carries the audio. Empty if there is nothing to hand over.
2989
2990        :param parent_player: The parent player that is switching protocol.
2991        :param parent_protocol_player: The protocol player taking the output over.
2992        :param previous_protocol: The parent's previous active output protocol, if any.
2993        """
2994        if previous_protocol in (None, "native"):
2995            return []
2996        if not (old_protocol_player := self.get_player(previous_protocol)):
2997            return []
2998        if old_protocol_player.player_id == parent_protocol_player.player_id:
2999            return []
3000        # Translate the old protocol's child members back to parent player IDs
3001        old_parent_members: list[str] = []
3002        for member_id in old_protocol_player.group_members:
3003            if member_id == old_protocol_player.player_id:
3004                continue
3005            if not (member_player := self.get_player(member_id)):
3006                continue
3007            parent_id = member_player.protocol_parent_id or member_id
3008            if parent_id != parent_player.player_id:
3009                old_parent_members.append(parent_id)
3010        self.logger.debug(
3011            "Stopping old protocol player %s before switching to %s, migrating members: %s",
3012            old_protocol_player.state.name,
3013            parent_protocol_player.state.name,
3014            old_parent_members,
3015        )
3016        # Use internal handler to stop the specific protocol player,
3017        # bypassing group/sync redirect and queue redirect logic.
3018        await self.mass.players._handle_cmd_stop(old_protocol_player.player_id)
3019        return old_parent_members
3020