UPSTREAM BASELINE: nextcloud/spreed v22.0.12 (без изменений)

Источник: https://github.com/nextcloud/spreed/archive/refs/tags/v22.0.12.tar.gz С этого коммита ветка официального Nextcloud Talk отрезана (решение владельца 2026-07-06). Все дальнейшие изменения — только наши; версии релизов: 22.0.12-f7.N.
2026-07-06 14:07:50 +00:00
commit 01acfa3b40
1716 changed files with 613013 additions and 0 deletions
@@ -0,0 +1,103 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Controller;
+
+use OCA\Talk\Exceptions\CannotReachRemoteException;
+use OCA\Talk\Federation\Proxy\TalkV1\ProxyRequest;
+use OCA\Talk\Model\Invitation;
+use OCA\Talk\Participant;
+use OCA\Talk\ResponseDefinitions;
+use OCA\Talk\Room;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\FileDisplayResponse;
+use OCP\Files\SimpleFS\InMemoryFile;
+
+/**
+ * @psalm-import-type TalkChatMentionSuggestion from ResponseDefinitions
+ * @psalm-import-type TalkChatMessageWithParent from ResponseDefinitions
+ */
+class AvatarController {
+	public function __construct(
+		protected ProxyRequest $proxy,
+	) {
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\AvatarController::getAvatar()
+	 *
+	 * @return FileDisplayResponse<Http::STATUS_OK, array{Content-Type: string}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Room avatar returned
+	 */
+	public function getAvatar(Room $room, ?Participant $participant, ?Invitation $invitation, bool $darkTheme): FileDisplayResponse {
+		if ($participant === null && $invitation === null) {
+			throw new CannotReachRemoteException('Must receive either participant or invitation');
+		}
+
+		$proxy = $this->proxy->get(
+			$participant ? $participant->getAttendee()->getInvitedCloudId() : $invitation->getLocalCloudId(),
+			$participant ? $participant->getAttendee()->getAccessToken() : $invitation->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/room/' . $room->getRemoteToken() . '/avatar' . ($darkTheme ? '/dark' : ''),
+		);
+
+		if ($proxy->getStatusCode() !== Http::STATUS_OK) {
+			$this->proxy->logUnexpectedStatusCode(__METHOD__, $proxy->getStatusCode(), (string)$proxy->getBody());
+			throw new CannotReachRemoteException('Avatar request had unexpected status code');
+		}
+
+		$content = $proxy->getBody();
+		if ($content === '') {
+			throw new CannotReachRemoteException('No avatar content received');
+		}
+
+		$file = new InMemoryFile($room->getToken(), $content);
+
+		$response = new FileDisplayResponse($file, Http::STATUS_OK, ['Content-Type' => $file->getMimeType()]);
+		// Cache for 1 day
+		$response->cacheFor(60 * 60 * 24, false, true);
+		return $response;
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\AvatarController::getUserProxyAvatar()
+	 *
+	 * @return FileDisplayResponse<Http::STATUS_OK, array{Content-Type: string}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: User avatar returned
+	 */
+	public function getUserProxyAvatar(string $remoteServer, string $user, int $size, bool $darkTheme): FileDisplayResponse {
+		$proxy = $this->proxy->get(
+			null,
+			null,
+			$remoteServer . '/index.php/avatar/' . $user . '/' . $size . ($darkTheme ? '/dark' : ''),
+		);
+
+		if ($proxy->getStatusCode() !== Http::STATUS_OK) {
+			if ($proxy->getStatusCode() !== Http::STATUS_NOT_FOUND) {
+				$this->proxy->logUnexpectedStatusCode(__METHOD__, $proxy->getStatusCode(), (string)$proxy->getBody());
+			}
+			throw new CannotReachRemoteException('Avatar request had unexpected status code');
+		}
+
+		$content = $proxy->getBody();
+		if ($content === '') {
+			throw new CannotReachRemoteException('No avatar content received');
+		}
+
+		$file = new InMemoryFile($user, $content);
+
+		$response = new FileDisplayResponse($file, Http::STATUS_OK, ['Content-Type' => $file->getMimeType()]);
+		// Cache for 1 day
+		$response->cacheFor(60 * 60 * 24, false, true);
+		return $response;
+	}
+}
@@ -0,0 +1,215 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Controller;
+
+use OCA\Talk\Exceptions\CannotReachRemoteException;
+use OCA\Talk\Federation\Proxy\TalkV1\ProxyRequest;
+use OCA\Talk\Federation\Proxy\TalkV1\UserConverter;
+use OCA\Talk\Model\Session;
+use OCA\Talk\Participant;
+use OCA\Talk\ResponseDefinitions;
+use OCA\Talk\Room;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\DataResponse;
+
+/**
+ * @psalm-import-type TalkCapabilities from ResponseDefinitions
+ * @psalm-import-type TalkCallPeer from ResponseDefinitions
+ * @psalm-import-type TalkParticipant from ResponseDefinitions
+ * @psalm-import-type TalkRoom from ResponseDefinitions
+ */
+class CallController {
+	public function __construct(
+		protected ProxyRequest $proxy,
+		protected UserConverter $userConverter,
+	) {
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\CallController::getPeersForCall()
+	 *
+	 * @param Room $room the federated room to get the call peers
+	 * @param Participant $participant the federated user to get the call peers
+	 * @return DataResponse<Http::STATUS_OK, list<TalkCallPeer>, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: List of peers in the call returned
+	 */
+	public function getPeersForCall(Room $room, Participant $participant): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v4/call/' . $room->getRemoteToken(),
+		);
+
+		/** @var list<TalkCallPeer> $data */
+		$data = $this->proxy->getOCSData($proxy);
+
+		/** @var list<TalkCallPeer> $data */
+		$data = $this->userConverter->convertAttendees($room, $data, 'actorType', 'actorId', 'displayName');
+
+		$statusCode = $proxy->getStatusCode();
+		if (!in_array($statusCode, [Http::STATUS_OK], true)) {
+			$this->proxy->logUnexpectedStatusCode(__METHOD__, $proxy->getStatusCode());
+			throw new CannotReachRemoteException();
+		}
+
+		return new DataResponse($data, $statusCode);
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\CallController::joinFederatedCall()
+	 *
+	 * @param Room $room the federated room to join the call in
+	 * @param Participant $participant the federated user that will join the
+	 *                                 call; the participant must have a session
+	 * @param int<0, 15> $flags In-Call flags
+	 * @psalm-param int-mask-of<Participant::FLAG_*> $flags
+	 * @param bool $silent Join the call silently
+	 * @param bool $recordingConsent Agreement to be recorded
+	 * @return DataResponse<Http::STATUS_OK|Http::STATUS_NOT_FOUND, null, array{}>|DataResponse<Http::STATUS_BAD_REQUEST, array{error: string}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Federated user is now in the call
+	 * 400: Conditions to join not met
+	 * 404: Room not found
+	 */
+	public function joinFederatedCall(Room $room, Participant $participant, int $flags, bool $silent, bool $recordingConsent): DataResponse {
+		$options = [
+			'sessionId' => $participant->getSession()->getSessionId(),
+			'flags' => $flags,
+			'silent' => $silent,
+			'recordingConsent' => $recordingConsent,
+		];
+
+		$proxy = $this->proxy->post(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v4/call/' . $room->getRemoteToken() . '/federation',
+			$options,
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if (!in_array($statusCode, [Http::STATUS_OK, Http::STATUS_BAD_REQUEST, Http::STATUS_NOT_FOUND], true)) {
+			$this->proxy->logUnexpectedStatusCode(__METHOD__, $proxy->getStatusCode());
+			throw new CannotReachRemoteException();
+		}
+
+		if ($statusCode === Http::STATUS_BAD_REQUEST) {
+			/** @var array{error: string} $data */
+			$data = $this->proxy->getOCSData($proxy, [Http::STATUS_BAD_REQUEST]);
+			return new DataResponse($data, $statusCode);
+		}
+
+		return new DataResponse(null, $statusCode);
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\CallController::ringAttendee()
+	 *
+	 * @param int $attendeeId ID of the attendee to ring
+	 * @return DataResponse<Http::STATUS_OK|Http::STATUS_NOT_FOUND, null, array{}>|DataResponse<Http::STATUS_BAD_REQUEST, array{error: string}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Attendee rang successfully
+	 * 400: Ringing attendee is not possible
+	 * 404: Attendee could not be found
+	 */
+	public function ringAttendee(Room $room, Participant $participant, int $attendeeId): DataResponse {
+		$proxy = $this->proxy->post(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v4/call/' . $room->getRemoteToken() . '/ring/' . $attendeeId,
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if (!in_array($statusCode, [Http::STATUS_OK, Http::STATUS_BAD_REQUEST, Http::STATUS_NOT_FOUND], true)) {
+			$this->proxy->logUnexpectedStatusCode(__METHOD__, $proxy->getStatusCode());
+			throw new CannotReachRemoteException();
+		}
+
+		if ($statusCode === Http::STATUS_BAD_REQUEST) {
+			/** @var array{error: string} $data */
+			$data = $this->proxy->getOCSData($proxy, [Http::STATUS_BAD_REQUEST]);
+			return new DataResponse($data, $statusCode);
+		}
+
+		return new DataResponse(null, $statusCode);
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\CallController::updateFederatedCallFlags()
+	 *
+	 * @param Room $room the federated room to update the call flags in
+	 * @param Participant $participant the federated user to update the call
+	 *                                 flags; the participant must have a session
+	 * @param int<0, 15> $flags New flags
+	 * @psalm-param int-mask-of<Participant::FLAG_*> $flags New flags
+	 * @return DataResponse<Http::STATUS_OK|Http::STATUS_BAD_REQUEST|Http::STATUS_NOT_FOUND, null, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: In-call flags updated successfully for federated user
+	 * 400: Updating in-call flags is not possible
+	 * 404: Room not found
+	 */
+	public function updateFederatedCallFlags(Room $room, Participant $participant, int $flags): DataResponse {
+		$options = [
+			'sessionId' => $participant->getSession()->getSessionId(),
+			'flags' => $flags,
+		];
+
+		$proxy = $this->proxy->put(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v4/call/' . $room->getRemoteToken() . '/federation',
+			$options,
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if (!in_array($statusCode, [Http::STATUS_OK, Http::STATUS_BAD_REQUEST, Http::STATUS_NOT_FOUND], true)) {
+			$this->proxy->logUnexpectedStatusCode(__METHOD__, $proxy->getStatusCode());
+			throw new CannotReachRemoteException();
+		}
+
+		return new DataResponse(null, $statusCode);
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\CallController::leaveFederatedCall()
+	 *
+	 * @param Room $room the federated room to leave the call in
+	 * @param Participant $participant the federated user that will leave the
+	 *                                 call; the participant must have a session
+	 * @return DataResponse<Http::STATUS_OK|Http::STATUS_NOT_FOUND, null, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Federated user left the call
+	 * 404: Room not found
+	 */
+	public function leaveFederatedCall(Room $room, Participant $participant): DataResponse {
+		$options = [
+			'sessionId' => $participant->getSession()->getSessionId(),
+		];
+
+		$proxy = $this->proxy->delete(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v4/call/' . $room->getRemoteToken() . '/federation',
+			$options,
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if (!in_array($statusCode, [Http::STATUS_OK, Http::STATUS_NOT_FOUND], true)) {
+			$this->proxy->logUnexpectedStatusCode(__METHOD__, $proxy->getStatusCode());
+			throw new CannotReachRemoteException();
+		}
+
+		return new DataResponse(null, $statusCode);
+	}
+}
@@ -0,0 +1,539 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Controller;
+
+use OCA\Talk\CachePrefix;
+use OCA\Talk\Chat\Notifier;
+use OCA\Talk\Exceptions\CannotReachRemoteException;
+use OCA\Talk\Federation\Proxy\TalkV1\ProxyRequest;
+use OCA\Talk\Federation\Proxy\TalkV1\UserConverter;
+use OCA\Talk\Model\Attendee;
+use OCA\Talk\Participant;
+use OCA\Talk\ResponseDefinitions;
+use OCA\Talk\Room;
+use OCA\Talk\Service\ParticipantService;
+use OCA\Talk\Service\RoomFormatter;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\DataResponse;
+use OCP\ICache;
+use OCP\ICacheFactory;
+
+/**
+ * @psalm-import-type TalkChatMentionSuggestion from ResponseDefinitions
+ * @psalm-import-type TalkChatMessage from ResponseDefinitions
+ * @psalm-import-type TalkChatMessageWithParent from ResponseDefinitions
+ * @psalm-import-type TalkRoom from ResponseDefinitions
+ */
+class ChatController {
+	protected ?ICache $proxyCacheMessages;
+
+	public function __construct(
+		protected ProxyRequest $proxy,
+		protected UserConverter $userConverter,
+		protected ParticipantService $participantService,
+		protected RoomFormatter $roomFormatter,
+		protected Notifier $notifier,
+		ICacheFactory $cacheFactory,
+	) {
+		$this->proxyCacheMessages = $cacheFactory->isAvailable() ? $cacheFactory->createDistributed(CachePrefix::FEDERATED_PCM) : null;
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\ChatController::sendMessage()
+	 *
+	 * @return DataResponse<Http::STATUS_CREATED, ?TalkChatMessageWithParent, array{X-Chat-Last-Common-Read?: numeric-string}>|DataResponse<Http::STATUS_BAD_REQUEST|Http::STATUS_NOT_FOUND|Http::STATUS_REQUEST_ENTITY_TOO_LARGE|Http::STATUS_TOO_MANY_REQUESTS, array{error: string}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 201: Message sent successfully
+	 * 400: Sending message is not possible
+	 * 404: Actor not found
+	 * 413: Message too long
+	 * 429: Mention rate limit exceeded (guests only)
+	 */
+	public function sendMessage(Room $room, Participant $participant, string $message, string $referenceId, int $replyTo, bool $silent, string $threadTitle, int $threadId): DataResponse {
+		$proxy = $this->proxy->post(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken(),
+			[
+				'message' => $message,
+				'actorDisplayName' => $participant->getAttendee()->getDisplayName(),
+				'referenceId' => $referenceId,
+				'replyTo' => $replyTo,
+				'silent' => $silent,
+				'threadTitle' => $threadTitle,
+				'threadId' => $threadId,
+			],
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if ($statusCode !== Http::STATUS_CREATED) {
+			if (!in_array($statusCode, [
+				Http::STATUS_BAD_REQUEST,
+				Http::STATUS_NOT_FOUND,
+				Http::STATUS_REQUEST_ENTITY_TOO_LARGE,
+				Http::STATUS_TOO_MANY_REQUESTS,
+			], true)) {
+				$statusCode = $this->proxy->logUnexpectedStatusCode(__METHOD__, $statusCode);
+			}
+			/** @var array{error: string} $data */
+			$data = $this->proxy->getOCSData($proxy, [Http::STATUS_CREATED]);
+			return new DataResponse($data, $statusCode);
+		}
+
+		/** @var ?TalkChatMessageWithParent $data */
+		$data = $this->proxy->getOCSData($proxy, [Http::STATUS_CREATED]);
+		if (!empty($data)) {
+			$data = $this->userConverter->convertMessage($room, $data);
+		} else {
+			$data = null;
+		}
+
+		$headers = [];
+		if ($proxy->getHeader('X-Chat-Last-Common-Read')) {
+			$headers['X-Chat-Last-Common-Read'] = (string)(int)$proxy->getHeader('X-Chat-Last-Common-Read');
+		}
+
+		return new DataResponse(
+			$data,
+			Http::STATUS_CREATED,
+			$headers,
+		);
+	}
+
+	/**
+	 * @return DataResponse<Http::STATUS_OK, list<TalkChatMessageWithParent>, array{'X-Chat-Last-Common-Read'?: numeric-string, X-Chat-Last-Given?: numeric-string}>|DataResponse<Http::STATUS_NOT_MODIFIED, null, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 *  200: Messages returned
+	 *  304: No messages
+	 *
+	 * @see \OCA\Talk\Controller\ChatController::getMessageContext()
+	 */
+	public function receiveMessages(
+		Room $room,
+		Participant $participant,
+		int $lookIntoFuture,
+		int $limit,
+		int $lastKnownMessageId,
+		int $lastCommonReadId,
+		int $timeout,
+		int $setReadMarker,
+		int $includeLastKnown,
+		int $noStatusUpdate,
+		int $markNotificationsAsRead): DataResponse {
+		$cacheKey = sha1(json_encode([$room->getRemoteServer(), $room->getRemoteToken()]));
+
+
+		if ($lookIntoFuture && $markNotificationsAsRead && $participant->getAttendee()->getActorType() === Attendee::ACTOR_USERS) {
+			$this->notifier->markMentionNotificationsRead($room, $participant->getAttendee()->getActorId());
+		}
+
+		if ($lookIntoFuture) {
+			if ($this->proxyCacheMessages instanceof ICache) {
+				for ($i = 0; $i <= $timeout; $i++) {
+					$cacheData = (int)$this->proxyCacheMessages->get($cacheKey);
+					if ($lastKnownMessageId !== $cacheData) {
+						break;
+					}
+					sleep(1);
+				}
+			} else {
+				// Poor-mans timeout, should later on cancel/trigger earlier,
+				// by checking the PCM database table
+				sleep(max(0, $timeout - 5));
+			}
+		}
+
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken(),
+			[
+				'lookIntoFuture' => $lookIntoFuture,
+				'limit' => $limit,
+				'lastKnownMessageId' => $lastKnownMessageId,
+				'lastCommonReadId' => $lastCommonReadId,
+				'timeout' => 0,
+				'setReadMarker' => $setReadMarker,
+				'includeLastKnown' => $includeLastKnown,
+				'noStatusUpdate' => $noStatusUpdate,
+				'markNotificationsAsRead' => $markNotificationsAsRead,
+			],
+		);
+
+		if ($lookIntoFuture && $setReadMarker) {
+			$this->participantService->updateUnreadInfoForProxyParticipant($participant,
+				0,
+				false,
+				false,
+				(int)($proxy->getHeader('X-Chat-Last-Given') ?: $lastKnownMessageId),
+			);
+		}
+
+		if ($proxy->getStatusCode() === Http::STATUS_NOT_MODIFIED) {
+			if ($lookIntoFuture && $this->proxyCacheMessages instanceof ICache) {
+				$cacheData = $this->proxyCacheMessages->get($cacheKey);
+				if ($cacheData === null || $cacheData < $lastKnownMessageId) {
+					$this->proxyCacheMessages->set($cacheKey, $lastKnownMessageId, 300);
+				}
+			}
+			return new DataResponse(null, Http::STATUS_NOT_MODIFIED);
+		}
+
+		$headers = [];
+		if ($proxy->getHeader('X-Chat-Last-Common-Read')) {
+			$headers['X-Chat-Last-Common-Read'] = (string)(int)$proxy->getHeader('X-Chat-Last-Common-Read');
+		}
+		if ($proxy->getHeader('X-Chat-Last-Given')) {
+			$headers['X-Chat-Last-Given'] = (string)(int)$proxy->getHeader('X-Chat-Last-Given');
+			if ($lookIntoFuture && $this->proxyCacheMessages instanceof ICache) {
+				$cacheData = $this->proxyCacheMessages->get($cacheKey);
+				if ($cacheData === null || $cacheData < $headers['X-Chat-Last-Given']) {
+					$this->proxyCacheMessages->set($cacheKey, (int)$headers['X-Chat-Last-Given'], 300);
+				}
+			}
+		}
+
+		/** @var list<TalkChatMessageWithParent> $data */
+		$data = $this->proxy->getOCSData($proxy);
+		/** @var list<TalkChatMessageWithParent> $data */
+		$data = $this->userConverter->convertMessages($room, $data);
+
+		return new DataResponse($data, Http::STATUS_OK, $headers);
+	}
+
+	/**
+	 * @return DataResponse<Http::STATUS_OK, list<TalkChatMessageWithParent>, array{'X-Chat-Last-Common-Read'?: numeric-string, X-Chat-Last-Given?: numeric-string}>|DataResponse<Http::STATUS_NOT_MODIFIED, null, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Message context returned
+	 * 304: No messages
+	 *
+	 * @see \OCA\Talk\Controller\ChatController::getMessageContext()
+	 */
+	public function getMessageContext(Room $room, Participant $participant, int $messageId, int $limit): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken() . '/' . $messageId . '/context',
+			[
+				'limit' => $limit,
+			],
+		);
+
+		if ($participant->getAttendee()->getActorType() === Attendee::ACTOR_USERS) {
+			$this->notifier->markMentionNotificationsRead($room, $participant->getAttendee()->getActorId());
+		}
+
+		if ($proxy->getStatusCode() === Http::STATUS_NOT_MODIFIED) {
+			return new DataResponse(null, Http::STATUS_NOT_MODIFIED);
+		}
+
+		$headers = [];
+		if ($proxy->getHeader('X-Chat-Last-Common-Read')) {
+			$headers['X-Chat-Last-Common-Read'] = (string)(int)$proxy->getHeader('X-Chat-Last-Common-Read');
+		}
+		if ($proxy->getHeader('X-Chat-Last-Given')) {
+			$headers['X-Chat-Last-Given'] = (string)(int)$proxy->getHeader('X-Chat-Last-Given');
+		}
+
+		/** @var list<TalkChatMessageWithParent> $data */
+		$data = $this->proxy->getOCSData($proxy);
+		/** @var list<TalkChatMessageWithParent> $data */
+		$data = $this->userConverter->convertMessages($room, $data);
+
+		return new DataResponse($data, Http::STATUS_OK, $headers);
+	}
+
+	/**
+	 * @return DataResponse<Http::STATUS_OK, array<string, list<TalkChatMessage>>, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: List of shared objects messages of each type returned
+	 *
+	 * @see \OCA\Talk\Controller\ChatController::getObjectsSharedInRoomOverview()
+	 */
+	public function getObjectsSharedInRoomOverview(Room $room, Participant $participant, int $limit): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken() . '/share/overview',
+			[
+				'limit' => $limit,
+			],
+		);
+
+		// We allow "200 OK" and "406 Not Acceptable" here, so that 33 against 32 and before is working well
+		/** @var array<string, list<TalkChatMessage>> $data */
+		$data = $this->proxy->getOCSData($proxy, [Http::STATUS_OK, Http::STATUS_NOT_ACCEPTABLE]);
+
+		$result = [];
+		foreach ($data as $type => $items) {
+			$result[$type] = array_values($this->userConverter->convertMessages($room, $items));
+		}
+
+		/** @var array<string, list<TalkChatMessage>> $result */
+		return new DataResponse($result, Http::STATUS_OK);
+	}
+
+	/**
+	 * @return DataResponse<Http::STATUS_OK, array<string, TalkChatMessage>, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: List of shared objects messages returned
+	 *
+	 * @see \OCA\Talk\Controller\ChatController::getObjectsSharedInRoom()
+	 */
+	public function getObjectsSharedInRoom(Room $room, Participant $participant, string $objectType, int $lastKnownMessageId, int $limit): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken() . '/share',
+			[
+				'objectType' => $objectType,
+				'lastKnownMessageId' => $lastKnownMessageId,
+				'limit' => $limit,
+			],
+		);
+
+		// We allow "200 OK" and "406 Not Acceptable" here, so that 33 against 32 and before is working well
+		/** @var array<string, TalkChatMessage> $data */
+		$data = $this->proxy->getOCSData($proxy, [Http::STATUS_OK, Http::STATUS_NOT_ACCEPTABLE]);
+		/** @var array<string, TalkChatMessage> $data */
+		$data = $this->userConverter->convertMessages($room, $data);
+
+		return new DataResponse($data, Http::STATUS_OK);
+	}
+
+	/**
+	 * @return DataResponse<Http::STATUS_OK|Http::STATUS_ACCEPTED, TalkChatMessageWithParent, array{X-Chat-Last-Common-Read?: numeric-string}>|DataResponse<Http::STATUS_BAD_REQUEST, array{error: string}, array{}>|DataResponse<Http::STATUS_FORBIDDEN|Http::STATUS_NOT_FOUND|Http::STATUS_METHOD_NOT_ALLOWED|Http::STATUS_REQUEST_ENTITY_TOO_LARGE, array{error: string}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Message edited successfully
+	 * 202: Message edited successfully, but a bot or Matterbridge is configured, so the information can be replicated to other services
+	 * 400: Editing message is not possible, e.g. when the new message is empty or the message is too old
+	 * 403: Missing permissions to edit message
+	 * 404: Message not found
+	 * 405: Editing this message type is not allowed
+	 *
+	 * @see \OCA\Talk\Controller\ChatController::editMessage()
+	 */
+	public function editMessage(Room $room, Participant $participant, int $messageId, string $message): DataResponse {
+		$proxy = $this->proxy->put(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken() . '/' . $messageId,
+			[
+				'message' => $message,
+			],
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if ($statusCode !== Http::STATUS_OK && $statusCode !== Http::STATUS_ACCEPTED) {
+			if (!in_array($statusCode, [
+				Http::STATUS_BAD_REQUEST,
+				Http::STATUS_FORBIDDEN,
+				Http::STATUS_NOT_FOUND,
+				Http::STATUS_METHOD_NOT_ALLOWED,
+				Http::STATUS_REQUEST_ENTITY_TOO_LARGE,
+			], true)) {
+				$statusCode = $this->proxy->logUnexpectedStatusCode(__METHOD__, $statusCode);
+				$data = ['error' => 'status'];
+			} elseif ($statusCode === Http::STATUS_BAD_REQUEST) {
+				/** @var array{error: string} $data */
+				$data = $this->proxy->getOCSData($proxy, [Http::STATUS_BAD_REQUEST]);
+			} else {
+				$data = [];
+			}
+			return new DataResponse($data, $statusCode);
+		}
+
+		/** @var TalkChatMessageWithParent $data */
+		$data = $this->proxy->getOCSData($proxy, [Http::STATUS_OK, Http::STATUS_ACCEPTED]);
+		$data = $this->userConverter->convertMessage($room, $data);
+
+		$headers = [];
+		if ($proxy->getHeader('X-Chat-Last-Common-Read')) {
+			$headers['X-Chat-Last-Common-Read'] = (string)(int)$proxy->getHeader('X-Chat-Last-Common-Read');
+		}
+
+		return new DataResponse(
+			$data,
+			$statusCode,
+			$headers,
+		);
+	}
+
+	/**
+	 * @return DataResponse<Http::STATUS_OK|Http::STATUS_ACCEPTED, TalkChatMessageWithParent, array{X-Chat-Last-Common-Read?: numeric-string}>|DataResponse<Http::STATUS_BAD_REQUEST|Http::STATUS_FORBIDDEN|Http::STATUS_NOT_FOUND|Http::STATUS_METHOD_NOT_ALLOWED, array{error: string}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Message deleted successfully
+	 * 202: Message deleted successfully, but a bot or Matterbridge is configured, so the information can be replicated elsewhere
+	 * 400: Deleting message is not possible
+	 * 403: Missing permissions to delete message
+	 * 404: Message not found
+	 * 405: Deleting this message type is not allowed
+	 *
+	 * @see \OCA\Talk\Controller\ChatController::deleteMessage()
+	 */
+	public function deleteMessage(Room $room, Participant $participant, int $messageId): DataResponse {
+		$proxy = $this->proxy->delete(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken() . '/' . $messageId,
+		);
+
+		/** @var Http::STATUS_OK|Http::STATUS_ACCEPTED|Http::STATUS_BAD_REQUEST|Http::STATUS_FORBIDDEN|Http::STATUS_NOT_FOUND|Http::STATUS_REQUEST_ENTITY_TOO_LARGE $statusCode */
+		$statusCode = $proxy->getStatusCode();
+
+		if ($statusCode !== Http::STATUS_OK && $statusCode !== Http::STATUS_ACCEPTED) {
+			if (in_array($statusCode, [
+				Http::STATUS_BAD_REQUEST,
+				Http::STATUS_FORBIDDEN,
+				Http::STATUS_NOT_FOUND,
+				Http::STATUS_REQUEST_ENTITY_TOO_LARGE,
+			], true)) {
+				$statusCode = $this->proxy->logUnexpectedStatusCode(__METHOD__, $statusCode);
+			}
+			return new DataResponse([], $statusCode);
+		}
+
+		/** @var TalkChatMessageWithParent $data */
+		$data = $this->proxy->getOCSData($proxy, [Http::STATUS_OK, Http::STATUS_ACCEPTED]);
+		$data = $this->userConverter->convertMessage($room, $data);
+
+		$headers = [];
+		if ($proxy->getHeader('X-Chat-Last-Common-Read')) {
+			$headers['X-Chat-Last-Common-Read'] = (string)(int)$proxy->getHeader('X-Chat-Last-Common-Read');
+		}
+
+		return new DataResponse(
+			$data,
+			$statusCode,
+			$headers,
+		);
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\ChatController::setReadMarker()
+	 *
+	 * @param 'json'|'xml' $responseFormat
+	 * @return DataResponse<Http::STATUS_OK, TalkRoom, array{X-Chat-Last-Common-Read?: numeric-string}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: List of mention suggestions returned
+	 */
+	public function setReadMarker(Room $room, Participant $participant, string $responseFormat, ?int $lastReadMessage): DataResponse {
+		$proxy = $this->proxy->post(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken() . '/read',
+			$lastReadMessage !== null ? [
+				'lastReadMessage' => $lastReadMessage,
+			] : [],
+		);
+
+		/** @var TalkRoom $data */
+		$data = $this->proxy->getOCSData($proxy);
+
+		$this->participantService->updateUnreadInfoForProxyParticipant(
+			$participant,
+			$data['unreadMessages'],
+			$data['unreadMention'],
+			$data['unreadMentionDirect'],
+			$data['lastReadMessage'],
+		);
+
+		$headers = $lastCommonRead = [];
+		if ($proxy->getHeader('X-Chat-Last-Common-Read')) {
+			$lastCommonRead[$room->getId()] = (int)$proxy->getHeader('X-Chat-Last-Common-Read');
+			$headers['X-Chat-Last-Common-Read'] = (string)$lastCommonRead[$room->getId()];
+		}
+
+		return new DataResponse($this->roomFormatter->formatRoom(
+			$responseFormat,
+			$lastCommonRead,
+			$room,
+			$participant,
+		), Http::STATUS_OK, $headers);
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\ChatController::markUnread()
+	 *
+	 * @param 'json'|'xml' $responseFormat
+	 * @return DataResponse<Http::STATUS_OK, TalkRoom, array{X-Chat-Last-Common-Read?: numeric-string}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: List of mention suggestions returned
+	 */
+	public function markUnread(Room $room, Participant $participant, string $responseFormat): DataResponse {
+		$proxy = $this->proxy->delete(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken() . '/read',
+		);
+
+		/** @var TalkRoom $data */
+		$data = $this->proxy->getOCSData($proxy);
+
+		$this->participantService->updateUnreadInfoForProxyParticipant(
+			$participant,
+			$data['unreadMessages'],
+			$data['unreadMention'],
+			$data['unreadMentionDirect'],
+			$data['lastReadMessage'],
+		);
+
+		$headers = $lastCommonRead = [];
+		if ($proxy->getHeader('X-Chat-Last-Common-Read')) {
+			$lastCommonRead[$room->getId()] = (int)$proxy->getHeader('X-Chat-Last-Common-Read');
+			$headers['X-Chat-Last-Common-Read'] = (string)$lastCommonRead[$room->getId()];
+		}
+
+		return new DataResponse($this->roomFormatter->formatRoom(
+			$responseFormat,
+			$lastCommonRead,
+			$room,
+			$participant,
+		), Http::STATUS_OK, $headers);
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\ChatController::mentions()
+	 *
+	 * @return DataResponse<Http::STATUS_OK, list<TalkChatMentionSuggestion>, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: List of mention suggestions returned
+	 */
+	public function mentions(Room $room, Participant $participant, string $search, int $limit, bool $includeStatus): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken() . '/mentions',
+			[
+				'search' => $search,
+				'limit' => $limit,
+				'includeStatus' => $includeStatus,
+			],
+		);
+
+		/** @var list<TalkChatMentionSuggestion> $data */
+		$data = $this->proxy->getOCSData($proxy);
+		/** @var list<TalkChatMentionSuggestion> $data */
+		$data = $this->userConverter->convertAttendees($room, $data, 'source', 'id', 'label');
+
+		// FIXME post-load status information
+		return new DataResponse($data, Http::STATUS_OK);
+	}
+}
@@ -0,0 +1,258 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Controller;
+
+use OCA\Talk\Exceptions\CannotReachRemoteException;
+use OCA\Talk\Exceptions\PollPropertyException;
+use OCA\Talk\Federation\Proxy\TalkV1\ProxyRequest;
+use OCA\Talk\Federation\Proxy\TalkV1\UserConverter;
+use OCA\Talk\Participant;
+use OCA\Talk\ResponseDefinitions;
+use OCA\Talk\Room;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\DataResponse;
+use Psr\Log\LoggerInterface;
+
+/**
+ * @psalm-import-type TalkPoll from ResponseDefinitions
+ * @psalm-import-type TalkPollDraft from ResponseDefinitions
+ */
+class PollController {
+	public function __construct(
+		protected ProxyRequest $proxy,
+		protected UserConverter $userConverter,
+		protected LoggerInterface $logger,
+	) {
+	}
+
+	/**
+	 * @return DataResponse<Http::STATUS_OK, list<TalkPollDraft>, array{}>|DataResponse<Http::STATUS_FORBIDDEN|Http::STATUS_NOT_FOUND, list<empty>, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Polls returned
+	 * 404: Polls not found
+	 *
+	 * @see \OCA\Talk\Controller\PollController::showPoll()
+	 */
+	public function getDraftsForRoom(Room $room, Participant $participant): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/poll/' . $room->getRemoteToken() . '/drafts',
+		);
+
+		$status = $proxy->getStatusCode();
+		if ($status === Http::STATUS_NOT_FOUND || $status === Http::STATUS_FORBIDDEN) {
+			return new DataResponse([], $status);
+		}
+
+		/** @var list<TalkPollDraft> $list */
+		$list = $this->proxy->getOCSData($proxy);
+
+		$data = [];
+		foreach ($list as $poll) {
+			$data[] = $this->userConverter->convertPoll($room, $poll);
+		}
+
+		return new DataResponse($data);
+	}
+
+	/**
+	 * @return DataResponse<Http::STATUS_OK, TalkPoll, array{}>|DataResponse<Http::STATUS_NOT_FOUND, array{error: string}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Poll returned
+	 * 404: Poll not found
+	 *
+	 * @see \OCA\Talk\Controller\PollController::showPoll()
+	 */
+	public function showPoll(Room $room, Participant $participant, int $pollId): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/poll/' . $room->getRemoteToken() . '/' . $pollId,
+		);
+
+		if ($proxy->getStatusCode() === Http::STATUS_NOT_FOUND) {
+			/** @var array{error?: string} $data */
+			$data = $this->proxy->getOCSData($proxy);
+			return new DataResponse(['error' => $data['error'] ?? 'poll'], Http::STATUS_NOT_FOUND);
+		}
+
+		/** @var TalkPoll $data */
+		$data = $this->proxy->getOCSData($proxy);
+		$data = $this->userConverter->convertPoll($room, $data);
+
+		return new DataResponse($data);
+	}
+
+	/**
+	 * @param list<int> $optionIds
+	 * @return DataResponse<Http::STATUS_OK, TalkPoll, array{}>|DataResponse<Http::STATUS_BAD_REQUEST|Http::STATUS_NOT_FOUND, array{error: string}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Voted successfully
+	 * 400: Voting is not possible
+	 * 404: Poll not found
+	 *
+	 * @see \OCA\Talk\Controller\PollController::votePoll()
+	 */
+	public function votePoll(Room $room, Participant $participant, int $pollId, array $optionIds): DataResponse {
+		$proxy = $this->proxy->post(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/poll/' . $room->getRemoteToken() . '/' . $pollId,
+			['optionIds' => $optionIds],
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if ($statusCode !== Http::STATUS_OK) {
+			if (!in_array($statusCode, [
+				Http::STATUS_BAD_REQUEST,
+				Http::STATUS_NOT_FOUND,
+			], true)) {
+				$statusCode = $this->proxy->logUnexpectedStatusCode(__METHOD__, $statusCode);
+			}
+			/** @var array{error?: string} $data */
+			$data = $this->proxy->getOCSData($proxy);
+			return new DataResponse(['error' => $data['error'] ?? 'poll'], $statusCode);
+		}
+
+		/** @var TalkPoll $data */
+		$data = $this->proxy->getOCSData($proxy);
+		$data = $this->userConverter->convertPoll($room, $data);
+
+		return new DataResponse($data);
+	}
+
+
+	/**
+	 * @return DataResponse<Http::STATUS_OK, TalkPollDraft, array{}>|DataResponse<Http::STATUS_CREATED, TalkPoll, array{}>|DataResponse<Http::STATUS_BAD_REQUEST, array{error: 'draft'|'options'|'poll'|'question'|'room'}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Draft created successfully
+	 * 201: Poll created successfully
+	 * 400: Creating poll is not possible
+	 *
+	 * @see \OCA\Talk\Controller\PollController::createPoll()
+	 */
+	public function createPoll(Room $room, Participant $participant, string $question, array $options, int $resultMode, int $maxVotes, bool $draft): DataResponse {
+		$proxy = $this->proxy->post(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/poll/' . $room->getRemoteToken(),
+			[
+				'question' => $question,
+				'options' => $options,
+				'resultMode' => $resultMode,
+				'maxVotes' => $maxVotes,
+				'draft' => $draft,
+			],
+		);
+
+		$status = $proxy->getStatusCode();
+		if ($status === Http::STATUS_BAD_REQUEST) {
+			$data = $this->proxy->getOCSData($proxy, [Http::STATUS_BAD_REQUEST]);
+			return new DataResponse($data, Http::STATUS_BAD_REQUEST);
+		}
+
+		/** @var TalkPoll $data */
+		$data = $this->proxy->getOCSData($proxy, [Http::STATUS_OK, Http::STATUS_CREATED]);
+		$data = $this->userConverter->convertPoll($room, $data);
+
+		if ($status === Http::STATUS_OK) {
+			return new DataResponse($data);
+		}
+		return new DataResponse($data, Http::STATUS_CREATED);
+	}
+
+	/**
+	 * @return DataResponse<Http::STATUS_OK, TalkPollDraft, array{}>|DataResponse<Http::STATUS_BAD_REQUEST|Http::STATUS_FORBIDDEN|Http::STATUS_NOT_FOUND, array{error: 'draft'|'options'|'poll'|'question'|'room'}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Draft created successfully
+	 * 201: Poll created successfully
+	 * 400: Creating poll is not possible
+	 *
+	 * @see \OCA\Talk\Controller\PollController::createPoll()
+	 */
+	public function updateDraftPoll(int $pollId, Room $room, Participant $participant, string $question, array $options, int $resultMode, int $maxVotes): DataResponse {
+		$proxy = $this->proxy->post(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/poll/' . $room->getRemoteToken() . '/draft/' . $pollId,
+			[
+				'question' => $question,
+				'options' => $options,
+				'resultMode' => $resultMode,
+				'maxVotes' => $maxVotes
+			],
+		);
+
+		$status = $proxy->getStatusCode();
+		if ($status === Http::STATUS_BAD_REQUEST) {
+			$data = $this->proxy->getOCSData($proxy, [Http::STATUS_BAD_REQUEST]);
+			return new DataResponse($data, Http::STATUS_BAD_REQUEST);
+		}
+
+		/** @var TalkPollDraft $data */
+		$data = $this->proxy->getOCSData($proxy, [Http::STATUS_OK, Http::STATUS_CREATED]);
+		$data = $this->userConverter->convertPoll($room, $data);
+
+		if ($status === Http::STATUS_OK) {
+			return new DataResponse($data);
+		}
+		return new DataResponse($data);
+	}
+
+	/**
+	 * @return DataResponse<Http::STATUS_OK, TalkPoll, array{}>|DataResponse<Http::STATUS_ACCEPTED, null, array{}>|DataResponse<Http::STATUS_BAD_REQUEST|Http::STATUS_FORBIDDEN|Http::STATUS_NOT_FOUND, array{error: 'poll'}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Poll closed successfully
+	 * 400: Poll already closed
+	 * 403: Missing permissions to close poll
+	 * 404: Poll not found
+	 *
+	 * @see \OCA\Talk\Controller\PollController::closePoll()
+	 */
+	public function closePoll(Room $room, Participant $participant, int $pollId): DataResponse {
+		$proxy = $this->proxy->delete(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/poll/' . $room->getRemoteToken() . '/' . $pollId,
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if ($statusCode !== Http::STATUS_OK) {
+			if (!in_array($statusCode, [
+				Http::STATUS_BAD_REQUEST,
+				Http::STATUS_FORBIDDEN,
+				Http::STATUS_NOT_FOUND,
+			], true)) {
+				$statusCode = $this->proxy->logUnexpectedStatusCode(__METHOD__, $statusCode);
+			}
+			/** @var array{error?: string} $data */
+			$data = $this->proxy->getOCSData($proxy);
+
+			if ($data['error'] !== PollPropertyException::REASON_POLL) {
+				$this->logger->error('Unhandled error in ' . __METHOD__ . ': ' . $data['error']);
+			}
+
+			return new DataResponse(['error' => PollPropertyException::REASON_POLL], $statusCode);
+		}
+
+		/** @var TalkPoll $data */
+		$data = $this->proxy->getOCSData($proxy);
+		$data = $this->userConverter->convertPoll($room, $data);
+
+		return new DataResponse($data);
+	}
+}
@@ -0,0 +1,166 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Controller;
+
+use OCA\Talk\Federation\Proxy\TalkV1\ProxyRequest;
+use OCA\Talk\Federation\Proxy\TalkV1\UserConverter;
+use OCA\Talk\Participant;
+use OCA\Talk\ResponseDefinitions;
+use OCA\Talk\Room;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\DataResponse;
+
+/**
+ * @psalm-import-type TalkReaction from ResponseDefinitions
+ */
+class ReactionController {
+	public function __construct(
+		protected ProxyRequest $proxy,
+		protected UserConverter $userConverter,
+	) {
+	}
+
+	/**
+	 * Add a reaction to a message
+	 *
+	 * @param int $messageId ID of the message
+	 * @psalm-param non-negative-int $messageId
+	 * @param string $reaction Emoji to add
+	 * @return DataResponse<Http::STATUS_OK|Http::STATUS_CREATED, array<string, list<TalkReaction>>|\stdClass, array{}>|DataResponse<Http::STATUS_BAD_REQUEST|Http::STATUS_NOT_FOUND, null, array{}>
+	 *
+	 * 200: Reaction already existed
+	 * 201: Reaction added successfully
+	 * 400: Adding reaction is not possible
+	 * 404: Message not found
+	 *
+	 * @see \OCA\Talk\Controller\ReactionController::react()
+	 */
+	public function react(Room $room, Participant $participant, int $messageId, string $reaction, string $format): DataResponse {
+		$proxy = $this->proxy->post(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/reaction/' . $room->getRemoteToken() . '/' . $messageId,
+			[
+				'reaction' => $reaction,
+			],
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if ($statusCode !== Http::STATUS_OK && $statusCode !== Http::STATUS_CREATED) {
+			if (!in_array($statusCode, [
+				Http::STATUS_BAD_REQUEST,
+				Http::STATUS_NOT_FOUND,
+			], true)) {
+				$statusCode = $this->proxy->logUnexpectedStatusCode(__METHOD__, $statusCode);
+			}
+			return new DataResponse(null, $statusCode);
+		}
+
+		/** @var array<string, list<TalkReaction>> $data */
+		$data = $this->proxy->getOCSData($proxy, [Http::STATUS_CREATED, Http::STATUS_OK]);
+		$data = $this->userConverter->convertReactionsList($room, $data);
+
+		return new DataResponse($this->formatReactions($format, $data), $statusCode);
+	}
+
+	/**
+	 * Delete a reaction from a message
+	 *
+	 * @param int $messageId ID of the message
+	 * @psalm-param non-negative-int $messageId
+	 * @param string $reaction Emoji to remove
+	 * @return DataResponse<Http::STATUS_OK, array<string, list<TalkReaction>>|\stdClass, array{}>|DataResponse<Http::STATUS_BAD_REQUEST|Http::STATUS_NOT_FOUND, null, array{}>
+	 *
+	 * 200: Reaction deleted successfully
+	 * 400: Deleting reaction is not possible
+	 * 404: Message not found
+	 *
+	 * @see \OCA\Talk\Controller\ReactionController::delete()
+	 */
+	public function delete(Room $room, Participant $participant, int $messageId, string $reaction, string $format): DataResponse {
+		$proxy = $this->proxy->delete(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/reaction/' . $room->getRemoteToken() . '/' . $messageId,
+			[
+				'reaction' => $reaction,
+			],
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if ($statusCode !== Http::STATUS_OK) {
+			if (!in_array($statusCode, [
+				Http::STATUS_BAD_REQUEST,
+				Http::STATUS_NOT_FOUND,
+			], true)) {
+				$statusCode = $this->proxy->logUnexpectedStatusCode(__METHOD__, $statusCode);
+			}
+			return new DataResponse(null, $statusCode);
+		}
+
+		/** @var array<string, list<TalkReaction>> $data */
+		$data = $this->proxy->getOCSData($proxy);
+		$data = $this->userConverter->convertReactionsList($room, $data);
+
+		return new DataResponse($this->formatReactions($format, $data), $statusCode);
+	}
+
+
+	/**
+	 * Get a list of reactions for a message
+	 *
+	 * @param int $messageId ID of the message
+	 * @psalm-param non-negative-int $messageId
+	 * @param string|null $reaction Emoji to filter
+	 * @return DataResponse<Http::STATUS_OK, array<string, list<TalkReaction>>|\stdClass, array{}>|DataResponse<Http::STATUS_NOT_FOUND, null, array{}>
+	 *
+	 * 200: Reactions returned
+	 * 404: Message or reaction not found
+	 *
+	 * @see \OCA\Talk\Controller\ReactionController::getReactions()
+	 */
+	public function getReactions(Room $room, Participant $participant, int $messageId, ?string $reaction, string $format): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/reaction/' . $room->getRemoteToken() . '/' . $messageId,
+			$reaction === null ? [] : [
+				'reaction' => $reaction,
+			],
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if ($statusCode !== Http::STATUS_OK) {
+			if ($statusCode !== Http::STATUS_NOT_FOUND) {
+				$this->proxy->logUnexpectedStatusCode(__METHOD__, $statusCode);
+			}
+			return new DataResponse(null, Http::STATUS_NOT_FOUND);
+		}
+
+		/** @var array<string, list<TalkReaction>> $data */
+		$data = $this->proxy->getOCSData($proxy);
+		$data = $this->userConverter->convertReactionsList($room, $data);
+
+		return new DataResponse($this->formatReactions($format, $data), $statusCode);
+	}
+
+	/**
+	 * @param array<string, list<TalkReaction>> $reactions
+	 * @return array<string, list<TalkReaction>>|\stdClass
+	 */
+	protected function formatReactions(string $format, array $reactions): array|\stdClass {
+		if ($format === 'json' && empty($reactions)) {
+			// Cheating here to make sure the reactions array is always a
+			// JSON object on the API, even when there is no reaction at all.
+			return new \stdClass();
+		}
+
+		return $reactions;
+	}
+}
@@ -0,0 +1,169 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Controller;
+
+use OCA\Talk\Exceptions\CannotReachRemoteException;
+use OCA\Talk\Federation\Proxy\TalkV1\ProxyRequest;
+use OCA\Talk\Federation\Proxy\TalkV1\UserConverter;
+use OCA\Talk\Model\Session;
+use OCA\Talk\Participant;
+use OCA\Talk\ResponseDefinitions;
+use OCA\Talk\Room;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\DataResponse;
+
+/**
+ * @psalm-import-type TalkCapabilities from ResponseDefinitions
+ * @psalm-import-type TalkParticipant from ResponseDefinitions
+ * @psalm-import-type TalkRoom from ResponseDefinitions
+ */
+class RoomController {
+	public function __construct(
+		protected ProxyRequest $proxy,
+		protected UserConverter $userConverter,
+	) {
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\RoomController::getParticipants()
+	 *
+	 * @return DataResponse<Http::STATUS_OK, list<TalkParticipant>, array{X-Nextcloud-Has-User-Statuses?: bool}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Participants returned
+	 * 403: Missing permissions for getting participants
+	 */
+	public function getParticipants(Room $room, Participant $participant): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v4/room/' . $room->getRemoteToken() . '/participants',
+		);
+
+		/** @var list<TalkParticipant> $data */
+		$data = $this->proxy->getOCSData($proxy);
+
+		/** @var list<TalkParticipant> $data */
+		$data = $this->userConverter->convertAttendees($room, $data, 'actorType', 'actorId', 'displayName');
+		$headers = [];
+		if ($proxy->getHeader('X-Nextcloud-Has-User-Statuses')) {
+			$headers['X-Nextcloud-Has-User-Statuses'] = (bool)$proxy->getHeader('X-Nextcloud-Has-User-Statuses');
+		}
+
+		return new DataResponse($data, Http::STATUS_OK, $headers);
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\RoomController::joinFederatedRoom()
+	 *
+	 * @param Room $room the federated room to join
+	 * @param Participant $participant the federated user to will join the room;
+	 *                                 the participant must have a session
+	 * @return DataResponse<Http::STATUS_OK|Http::STATUS_NOT_FOUND, array<empty>, array{X-Nextcloud-Talk-Proxy-Hash: string}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Federated user joined the room
+	 * 404: Room not found
+	 */
+	public function joinFederatedRoom(Room $room, Participant $participant): DataResponse {
+		$options = [
+			'sessionId' => $participant->getSession()->getSessionId(),
+		];
+
+		$proxy = $this->proxy->post(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v4/room/' . $room->getRemoteToken() . '/federation/active',
+			$options,
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if (!in_array($statusCode, [Http::STATUS_OK, Http::STATUS_NOT_FOUND], true)) {
+			$this->proxy->logUnexpectedStatusCode(__METHOD__, $proxy->getStatusCode());
+			throw new CannotReachRemoteException();
+		}
+
+		$headers = ['X-Nextcloud-Talk-Proxy-Hash' => $this->proxy->overwrittenRemoteTalkHash($proxy->getHeader('X-Nextcloud-Talk-Hash'))];
+
+		/** @var TalkRoom[] $data */
+		$data = $this->proxy->getOCSData($proxy);
+
+		$data = $this->userConverter->convertAttendee($room, $data, 'actorType', 'actorId', 'displayName');
+
+		return new DataResponse($data, $statusCode, $headers);
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\RoomController::leaveFederatedRoom()
+	 *
+	 * @param Room $room the federated room to leave
+	 * @param Participant $participant the federated user that will leave the
+	 *                                 room; the participant must have a session
+	 * @return DataResponse<Http::STATUS_OK, array<empty>, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Federated user left the room
+	 */
+	public function leaveFederatedRoom(Room $room, Participant $participant): DataResponse {
+		$options = [
+			'sessionId' => $participant->getSession()->getSessionId(),
+		];
+
+		$proxy = $this->proxy->delete(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v4/room/' . $room->getRemoteToken() . '/federation/active',
+			$options,
+		);
+
+		// STATUS_NOT_FOUND is not taken into account, as it should happen only
+		// for non-federation requests.
+		$statusCode = $proxy->getStatusCode();
+		if (!in_array($statusCode, [Http::STATUS_OK], true)) {
+			$this->proxy->logUnexpectedStatusCode(__METHOD__, $proxy->getStatusCode());
+			throw new CannotReachRemoteException();
+		}
+
+		return new DataResponse([], $statusCode);
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\RoomController::getCapabilities()
+	 *
+	 * @return DataResponse<Http::STATUS_OK, TalkCapabilities|array<empty>, array{X-Nextcloud-Talk-Hash: string}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Get capabilities successfully
+	 */
+	public function getCapabilities(Room $room, Participant $participant): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v4/room/' . $room->getRemoteToken() . '/capabilities',
+		);
+
+		/** @var TalkCapabilities|array<empty> $data */
+		$data = $this->proxy->getOCSData($proxy);
+
+		$headers = [
+			'X-Nextcloud-Talk-Hash' => $this->proxy->overwrittenRemoteTalkHash($proxy->getHeader('X-Nextcloud-Talk-Hash')),
+		];
+
+		return new DataResponse($data, Http::STATUS_OK, $headers);
+	}
+
+	/**
+	 * @return array<string, mixed>|\stdClass
+	 */
+	protected function emptyArray(): array|\stdClass {
+		// Cheating here to make sure the array is always a
+		// JSON object on the API, even when there is no entry at all.
+		return new \stdClass();
+	}
+}
@@ -0,0 +1,58 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Controller;
+
+use OCA\Talk\Exceptions\CannotReachRemoteException;
+use OCA\Talk\Federation\Proxy\TalkV1\ProxyRequest;
+use OCA\Talk\Participant;
+use OCA\Talk\ResponseDefinitions;
+use OCA\Talk\Room;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\DataResponse;
+
+/**
+ * @psalm-import-type TalkSignalingSettings from ResponseDefinitions
+ */
+class SignalingController {
+	public function __construct(
+		protected ProxyRequest $proxy,
+	) {
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\SignalingController::getSettings()
+	 *
+	 * @return DataResponse<Http::STATUS_OK, TalkSignalingSettings, array{}>|DataResponse<Http::STATUS_NOT_FOUND, array<empty>, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Signaling settings returned
+	 * 404: Room not found
+	 */
+	public function getSettings(Room $room, Participant $participant): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v3/signaling/settings',
+			[
+				'token' => $room->getRemoteToken(),
+			],
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if (!in_array($statusCode, [Http::STATUS_OK, Http::STATUS_NOT_FOUND], true)) {
+			$this->proxy->logUnexpectedStatusCode(__METHOD__, $proxy->getStatusCode());
+			throw new CannotReachRemoteException();
+		}
+
+		/** @var TalkSignalingSettings|array<empty> $data */
+		$data = $this->proxy->getOCSData($proxy);
+
+		return new DataResponse($data, $statusCode);
+	}
+}
@@ -0,0 +1,197 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Controller;
+
+use OCA\Talk\Chat\Notifier;
+use OCA\Talk\Exceptions\CannotReachRemoteException;
+use OCA\Talk\Federation\Proxy\TalkV1\ProxyRequest;
+use OCA\Talk\Federation\Proxy\TalkV1\UserConverter;
+use OCA\Talk\Participant;
+use OCA\Talk\ResponseDefinitions;
+use OCA\Talk\Room;
+use OCA\Talk\Service\ParticipantService;
+use OCA\Talk\Service\RoomFormatter;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\DataResponse;
+use OCP\ICacheFactory;
+
+/**
+ * @psalm-import-type TalkThreadInfo from ResponseDefinitions
+ * @psalm-import-type TalkRoom from ResponseDefinitions
+ */
+class ThreadController {
+
+	public function __construct(
+		protected ProxyRequest $proxy,
+		protected UserConverter $userConverter,
+		protected ParticipantService $participantService,
+		protected RoomFormatter $roomFormatter,
+		protected Notifier $notifier,
+		ICacheFactory $cacheFactory,
+	) {
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\ThreadController::getRecentActiveThreads()
+	 *
+	 * @return DataResponse<Http::STATUS_OK, list<TalkThreadInfo>, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: List of threads returned
+	 */
+	public function getRecentActiveThreads(Room $room, Participant $participant, int $limit): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken() . '/threads/recent',
+			[
+				'limit' => $limit,
+			],
+		);
+
+		/** @var list<TalkThreadInfo> $data */
+		$data = $this->proxy->getOCSData($proxy);
+		if (!empty($data)) {
+			$data = $this->userConverter->convertThreadInfos($room, $data);
+		}
+
+		return new DataResponse($data);
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\ThreadController::getThread()
+	 *
+	 * @psalm-param non-negative-int $threadId
+	 * @return DataResponse<Http::STATUS_OK, TalkThreadInfo, array{}>|DataResponse<Http::STATUS_NOT_FOUND, array{error: 'thread'|'status'}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Thread info returned
+	 * 404: Thread not found
+	 */
+	public function getThread(Room $room, Participant $participant, int $threadId): DataResponse {
+		$proxy = $this->proxy->get(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken() . '/threads/' . $threadId,
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if ($statusCode !== Http::STATUS_OK) {
+			if ($statusCode !== Http::STATUS_NOT_FOUND) {
+				$this->proxy->logUnexpectedStatusCode(__METHOD__, $statusCode);
+				$data = ['error' => 'status'];
+			} else {
+				/** @var array{error: 'thread'} $data */
+				$data = $this->proxy->getOCSData($proxy, [Http::STATUS_NOT_FOUND]);
+			}
+			return new DataResponse($data, Http::STATUS_NOT_FOUND);
+		}
+
+		/** @var TalkThreadInfo $data */
+		$data = $this->proxy->getOCSData($proxy);
+		$data = $this->userConverter->convertThreadInfo($room, $data);
+
+		return new DataResponse($data, Http::STATUS_OK);
+	}
+
+	/**
+	 * @see \OCA\Talk\Controller\ThreadController::setNotificationLevel()
+	 *
+	 * @psalm-param non-negative-int $threadId
+	 * @return DataResponse<Http::STATUS_OK, TalkThreadInfo, array{}>|DataResponse<Http::STATUS_BAD_REQUEST, array{error: 'title'}, array{}>|DataResponse<Http::STATUS_NOT_FOUND, array{error: 'thread'}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Thread renamed successfully
+	 * 400: When the provided title is empty
+	 * 404: Thread not found
+	 */
+	public function renameThread(Room $room, Participant $participant, int $threadId, string $threadTitle): DataResponse {
+		$proxy = $this->proxy->put(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken() . '/threads/' . $threadId,
+			['threadTitle' => $threadTitle],
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if ($statusCode !== Http::STATUS_OK) {
+			if (!in_array($statusCode, [
+				Http::STATUS_BAD_REQUEST,
+				Http::STATUS_NOT_FOUND,
+			], true)) {
+				$statusCode = $this->proxy->logUnexpectedStatusCode(__METHOD__, $statusCode);
+				$data = ['error' => 'thread'];
+			} elseif ($statusCode === Http::STATUS_BAD_REQUEST) {
+				/** @var array{error: 'title'} $data */
+				$data = $this->proxy->getOCSData($proxy, [
+					Http::STATUS_BAD_REQUEST,
+				]);
+			} else {
+				/** @var array{error: 'thread'} $data */
+				$data = $this->proxy->getOCSData($proxy, [
+					Http::STATUS_NOT_FOUND,
+				]);
+			}
+			return new DataResponse($data, $statusCode);
+		}
+
+		/** @var TalkThreadInfo $data */
+		$data = $this->proxy->getOCSData($proxy);
+		$data = $this->userConverter->convertThreadInfo($room, $data);
+
+		return new DataResponse($data, Http::STATUS_OK);
+	}
+
+
+	/**
+	 * @see \OCA\Talk\Controller\ThreadController::setNotificationLevel()
+	 *
+	 * @psalm-param non-negative-int $messageId
+	 * @psalm-param Participant::NOTIFY_* $level
+	 * @return DataResponse<Http::STATUS_OK, TalkThreadInfo, array{}>|DataResponse<Http::STATUS_BAD_REQUEST|Http::STATUS_NOT_FOUND, array{error: 'level'|'message'|'status'|'top-most'}, array{}>
+	 * @throws CannotReachRemoteException
+	 *
+	 * 200: Successfully set notification level for thread
+	 * 400: Notification level was invalid
+	 * 404: Message or top most message not found
+	 */
+	public function setNotificationLevel(Room $room, Participant $participant, int $messageId, int $level): DataResponse {
+		$proxy = $this->proxy->post(
+			$participant->getAttendee()->getInvitedCloudId(),
+			$participant->getAttendee()->getAccessToken(),
+			$room->getRemoteServer() . '/ocs/v2.php/apps/spreed/api/v1/chat/' . $room->getRemoteToken() . '/threads/' . $messageId . '/notify',
+			['level' => $level],
+		);
+
+		$statusCode = $proxy->getStatusCode();
+		if ($statusCode !== Http::STATUS_OK) {
+			if (!in_array($statusCode, [
+				Http::STATUS_BAD_REQUEST,
+				Http::STATUS_NOT_FOUND,
+			], true)) {
+				$statusCode = $this->proxy->logUnexpectedStatusCode(__METHOD__, $statusCode);
+				$data = ['error' => 'status'];
+			} else {
+				/** @var array{error: 'level'|'message'|'top-most'} $data */
+				$data = $this->proxy->getOCSData($proxy, [
+					Http::STATUS_BAD_REQUEST,
+					Http::STATUS_NOT_FOUND,
+				]);
+			}
+			return new DataResponse($data, $statusCode);
+		}
+
+		/** @var TalkThreadInfo $data */
+		$data = $this->proxy->getOCSData($proxy);
+		$data = $this->userConverter->convertThreadInfo($room, $data);
+
+		return new DataResponse($data, Http::STATUS_OK);
+	}
+}
@@ -0,0 +1,50 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Listener;
+
+use OCA\Talk\Config;
+use OCA\Talk\Federation\CloudFederationProviderTalk;
+use OCA\Talk\Federation\FederationManager;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventListener;
+use OCP\OCM\Events\ResourceTypeRegisterEvent;
+use OCP\OCM\IOCMProvider;
+
+/**
+ * @template-implements IEventListener<Event>
+ */
+class ResourceTypeRegisterListener implements IEventListener {
+
+	public function __construct(
+		protected Config $talkConfig,
+		protected IOCMProvider $provider,
+		protected CloudFederationProviderTalk $talkProvider,
+	) {
+	}
+
+	#[\Override]
+	public function handle(Event $event): void {
+		if (!$event instanceof ResourceTypeRegisterEvent) {
+			// Unrelated
+			return;
+		}
+
+		if (!$this->talkConfig->isFederationEnabled()) {
+			return;
+		}
+
+		$event->registerResourceType(
+			FederationManager::TALK_ROOM_RESOURCE,
+			$this->talkProvider->getSupportedShareTypes(),
+			[
+				'talk-v1' => '/ocs/v2.php/apps/spreed/api/',
+			]
+		);
+	}
+}
@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Notifier;
+
+use OCA\Talk\Events\BeforeRoomDeletedEvent;
+use OCA\Talk\Federation\BackendNotifier;
+use OCA\Talk\Model\Attendee;
+use OCA\Talk\Service\ParticipantService;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventListener;
+use OCP\Federation\ICloudIdManager;
+
+/**
+ * @template-implements IEventListener<Event>
+ */
+class BeforeRoomDeletedListener implements IEventListener {
+	public function __construct(
+		protected BackendNotifier $backendNotifier,
+		protected ParticipantService $participantService,
+		protected ICloudIdManager $cloudIdManager,
+	) {
+	}
+
+	#[\Override]
+	public function handle(Event $event): void {
+		if (!$event instanceof BeforeRoomDeletedEvent) {
+			return;
+		}
+
+		$participants = $this->participantService->getParticipantsByActorType($event->getRoom(), Attendee::ACTOR_FEDERATED_USERS);
+		foreach ($participants as $participant) {
+			$cloudId = $this->cloudIdManager->resolveCloudId($participant->getAttendee()->getActorId());
+
+			$this->backendNotifier->sendRemoteUnShare(
+				$cloudId->getRemote(),
+				$participant->getAttendee()->getId(),
+				$participant->getAttendee()->getAccessToken(),
+			);
+		}
+	}
+}
@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Notifier;
+
+use OCA\Talk\Events\AttendeeRemovedEvent;
+use OCA\Talk\Model\Attendee;
+use OCA\Talk\Model\RetryNotificationMapper;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventListener;
+
+/**
+ * @template-implements IEventListener<Event>
+ */
+class CancelRetryOCMListener implements IEventListener {
+	public function __construct(
+		protected RetryNotificationMapper $retryNotificationMapper,
+	) {
+	}
+
+	#[\Override]
+	public function handle(Event $event): void {
+		if (!$event instanceof AttendeeRemovedEvent) {
+			return;
+		}
+
+		$attendee = $event->getAttendee();
+		if ($attendee->getActorType() !== Attendee::ACTOR_FEDERATED_USERS) {
+			return;
+		}
+
+		$this->retryNotificationMapper->deleteByProviderId(
+			(string)$event->getAttendee()->getId()
+		);
+	}
+}
@@ -0,0 +1,128 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Notifier;
+
+use OCA\Talk\Chat\ChatManager;
+use OCA\Talk\Chat\MessageParser;
+use OCA\Talk\Events\AAttendeeRemovedEvent;
+use OCA\Talk\Events\ASystemMessageSentEvent;
+use OCA\Talk\Events\ChatMessageSentEvent;
+use OCA\Talk\Events\SystemMessageSentEvent;
+use OCA\Talk\Events\SystemMessagesMultipleSentEvent;
+use OCA\Talk\Federation\BackendNotifier;
+use OCA\Talk\Model\Attendee;
+use OCA\Talk\Model\ProxyCacheMessage;
+use OCA\Talk\Service\ParticipantService;
+use OCP\Comments\IComment;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventListener;
+use OCP\Federation\ICloudIdManager;
+use OCP\L10N\IFactory;
+
+/**
+ * @template-implements IEventListener<Event>
+ */
+class MessageSentListener implements IEventListener {
+	public function __construct(
+		protected BackendNotifier $backendNotifier,
+		protected ParticipantService $participantService,
+		protected ICloudIdManager $cloudIdManager,
+		protected MessageParser $messageParser,
+		protected IFactory $l10nFactory,
+		protected ChatManager $chatManager,
+	) {
+	}
+
+	#[\Override]
+	public function handle(Event $event): void {
+		if (!$event instanceof ChatMessageSentEvent
+			&& !$event instanceof SystemMessageSentEvent
+			&& !$event instanceof SystemMessagesMultipleSentEvent) {
+			return;
+		}
+
+		// FIXME once we store/cache the info skip this if the room has no federation participant
+		// if (!$event->getRoom()->hasFederatedParticipants()) {
+		// return;
+		// }
+
+		// Try to have as neutral as possible messages
+		$l = $this->l10nFactory->get('spreed', 'en', 'en');
+		$chatMessage = $this->messageParser->createMessage($event->getRoom(), null, $event->getComment(), $l);
+		$this->messageParser->parseMessage($chatMessage);
+
+		$systemMessage = $chatMessage->getMessageType() === ChatManager::VERB_SYSTEM ? $chatMessage->getMessageRaw() : '';
+		if ($systemMessage !== 'message_edited'
+			&& $systemMessage !== 'message_deleted'
+			&& $event instanceof ASystemMessageSentEvent
+			&& $event->shouldSkipLastActivityUpdate()) {
+			return;
+		}
+
+		if (!$chatMessage->getVisibility()) {
+			return;
+		}
+
+		$expireDate = $event->getComment()->getExpireDate();
+		$creationDate = $event->getComment()->getCreationDateTime();
+
+		$metaData = $event->getComment()->getMetaData() ?? [];
+		$parent = $event->getParent();
+		if ($parent instanceof IComment) {
+			$metaData[ProxyCacheMessage::METADATA_REPLY_TO_ACTOR_TYPE] = $parent->getActorType();
+			$metaData[ProxyCacheMessage::METADATA_REPLY_TO_ACTOR_ID] = $parent->getActorId();
+			$metaData[ProxyCacheMessage::METADATA_REPLY_TO_MESSAGE_ID] = (int)$parent->getId();
+		}
+
+		$messageData = [
+			'remoteMessageId' => (int)$event->getComment()->getId(),
+			'actorType' => $chatMessage->getActorType(),
+			'actorId' => $chatMessage->getActorId(),
+			'actorDisplayName' => $chatMessage->getActorDisplayName(),
+			'messageType' => $chatMessage->getMessageType(),
+			'systemMessage' => $systemMessage,
+			'expirationDatetime' => $expireDate ? $expireDate->format(\DateTime::ATOM) : '',
+			'message' => $chatMessage->getMessage(),
+			'messageParameter' => json_encode($chatMessage->getMessageParameters(), JSON_THROW_ON_ERROR),
+			'creationDatetime' => $creationDate->format(\DateTime::ATOM),
+			'metaData' => json_encode($metaData, JSON_THROW_ON_ERROR),
+		];
+
+		$participants = $this->participantService->getParticipantsByActorType($event->getRoom(), Attendee::ACTOR_FEDERATED_USERS);
+		foreach ($participants as $participant) {
+			$attendee = $participant->getAttendee();
+			$cloudId = $this->cloudIdManager->resolveCloudId($attendee->getActorId());
+
+			$lastReadMessage = $attendee->getLastReadMessage();
+			$lastMention = $attendee->getLastMentionMessage();
+			$lastMentionDirect = $attendee->getLastMentionDirect();
+
+			$unreadInfo = [
+				'lastReadMessage' => $lastReadMessage,
+				'unreadMessages' => $this->chatManager->getUnreadCount($event->getRoom(), $lastReadMessage),
+				'unreadMention' => $lastMention !== 0 && $lastReadMessage < $lastMention,
+				'unreadMentionDirect' => $lastMentionDirect !== 0 && $lastReadMessage < $lastMentionDirect,
+			];
+
+			$success = $this->backendNotifier->sendMessageUpdate(
+				$cloudId->getRemote(),
+				$participant->getAttendee()->getId(),
+				$participant->getAttendee()->getAccessToken(),
+				$event->getRoom()->getToken(),
+				$messageData,
+				$unreadInfo,
+			);
+
+			if ($success === null) {
+				$this->participantService->removeAttendee($event->getRoom(), $participant, AAttendeeRemovedEvent::REASON_LEFT);
+			}
+		}
+	}
+}
@@ -0,0 +1,72 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Notifier;
+
+use OCA\Talk\Events\AAttendeeRemovedEvent;
+use OCA\Talk\Events\AParticipantModifiedEvent;
+use OCA\Talk\Events\ParticipantModifiedEvent;
+use OCA\Talk\Federation\BackendNotifier;
+use OCA\Talk\Model\Attendee;
+use OCA\Talk\Participant;
+use OCA\Talk\Service\ParticipantService;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventListener;
+use OCP\Federation\ICloudId;
+use OCP\Federation\ICloudIdManager;
+
+/**
+ * @template-implements IEventListener<Event>
+ */
+class ParticipantModifiedListener implements IEventListener {
+	public function __construct(
+		protected BackendNotifier $backendNotifier,
+		protected ParticipantService $participantService,
+		protected ICloudIdManager $cloudIdManager,
+	) {
+	}
+
+	#[\Override]
+	public function handle(Event $event): void {
+		if (!$event instanceof ParticipantModifiedEvent) {
+			return;
+		}
+
+		$participant = $event->getParticipant();
+		if ($participant->getAttendee()->getActorType() !== Attendee::ACTOR_FEDERATED_USERS) {
+			return;
+		}
+
+		if (!in_array($event->getProperty(), [
+			AParticipantModifiedEvent::PROPERTY_PERMISSIONS,
+			AParticipantModifiedEvent::PROPERTY_RESEND_CALL,
+		], true)) {
+			return;
+		}
+
+		// For modifying participants we only notify the affected participant's server
+		$cloudId = $this->cloudIdManager->resolveCloudId($participant->getAttendee()->getActorId());
+		$success = $this->notifyParticipantModified($cloudId, $participant, $event);
+
+		if ($success === null) {
+			$this->participantService->removeAttendee($event->getRoom(), $participant, AAttendeeRemovedEvent::REASON_LEFT);
+		}
+	}
+
+	private function notifyParticipantModified(ICloudId $cloudId, Participant $participant, AParticipantModifiedEvent $event): ?bool {
+		return $this->backendNotifier->sendParticipantModifiedUpdate(
+			$cloudId->getRemote(),
+			$participant->getAttendee()->getId(),
+			$participant->getAttendee()->getAccessToken(),
+			$event->getRoom()->getToken(),
+			$event->getProperty(),
+			$event->getNewValue(),
+			$event->getOldValue(),
+		);
+	}
+}
@@ -0,0 +1,154 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1\Notifier;
+
+use OCA\Talk\Events\AAttendeeRemovedEvent;
+use OCA\Talk\Events\ALobbyModifiedEvent;
+use OCA\Talk\Events\AParticipantModifiedEvent;
+use OCA\Talk\Events\ARoomModifiedEvent;
+use OCA\Talk\Events\CallEndedEvent;
+use OCA\Talk\Events\CallEndedForEveryoneEvent;
+use OCA\Talk\Events\CallStartedEvent;
+use OCA\Talk\Events\LobbyModifiedEvent;
+use OCA\Talk\Events\RoomModifiedEvent;
+use OCA\Talk\Federation\BackendNotifier;
+use OCA\Talk\Model\Attendee;
+use OCA\Talk\Participant;
+use OCA\Talk\Service\ParticipantService;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventListener;
+use OCP\Federation\ICloudId;
+use OCP\Federation\ICloudIdManager;
+
+/**
+ * @template-implements IEventListener<Event>
+ */
+class RoomModifiedListener implements IEventListener {
+	public function __construct(
+		protected BackendNotifier $backendNotifier,
+		protected ParticipantService $participantService,
+		protected ICloudIdManager $cloudIdManager,
+	) {
+	}
+
+	#[\Override]
+	public function handle(Event $event): void {
+		if (!$event instanceof CallStartedEvent
+				&& !$event instanceof CallEndedEvent
+				&& !$event instanceof CallEndedForEveryoneEvent
+				&& !$event instanceof LobbyModifiedEvent
+				&& !$event instanceof RoomModifiedEvent) {
+			return;
+		}
+
+		if (!in_array($event->getProperty(), [
+			ARoomModifiedEvent::PROPERTY_ACTIVE_SINCE,
+			ARoomModifiedEvent::PROPERTY_AVATAR,
+			ARoomModifiedEvent::PROPERTY_CALL_RECORDING,
+			ARoomModifiedEvent::PROPERTY_DEFAULT_PERMISSIONS,
+			ARoomModifiedEvent::PROPERTY_DESCRIPTION,
+			ARoomModifiedEvent::PROPERTY_IN_CALL,
+			ARoomModifiedEvent::PROPERTY_LOBBY,
+			ARoomModifiedEvent::PROPERTY_MENTION_PERMISSIONS,
+			ARoomModifiedEvent::PROPERTY_MESSAGE_EXPIRATION,
+			ARoomModifiedEvent::PROPERTY_NAME,
+			ARoomModifiedEvent::PROPERTY_READ_ONLY,
+			ARoomModifiedEvent::PROPERTY_RECORDING_CONSENT,
+			ARoomModifiedEvent::PROPERTY_SIP_ENABLED,
+			ARoomModifiedEvent::PROPERTY_TYPE,
+		], true)) {
+			return;
+		}
+
+		if ($event->getRoom()->isFederatedConversation()) {
+			return;
+		}
+
+		$participants = $this->participantService->getParticipantsByActorType($event->getRoom(), Attendee::ACTOR_FEDERATED_USERS);
+		foreach ($participants as $participant) {
+			$cloudId = $this->cloudIdManager->resolveCloudId($participant->getAttendee()->getActorId());
+
+			if ($event instanceof CallStartedEvent) {
+				$success = $this->notifyCallStarted($cloudId, $participant, $event);
+			} elseif ($event instanceof CallEndedEvent || $event instanceof CallEndedForEveryoneEvent) {
+				$success = $this->notifyCallEnded($cloudId, $participant, $event);
+			} elseif ($event instanceof ALobbyModifiedEvent) {
+				$success = $this->notifyLobbyModified($cloudId, $participant, $event);
+			} else {
+				$success = $this->notifyRoomModified($cloudId, $participant, $event);
+			}
+
+			if ($success === null) {
+				$this->participantService->removeAttendee($event->getRoom(), $participant, AAttendeeRemovedEvent::REASON_LEFT);
+			}
+		}
+	}
+
+	private function notifyCallStarted(ICloudId $cloudId, Participant $participant, CallStartedEvent $event) {
+		$details = [];
+		if ($event->getDetail(AParticipantModifiedEvent::DETAIL_IN_CALL_SILENT)) {
+			$details = [AParticipantModifiedEvent::DETAIL_IN_CALL_SILENT => true];
+		}
+
+		return $this->backendNotifier->sendCallStarted(
+			$cloudId->getRemote(),
+			$participant->getAttendee()->getId(),
+			$participant->getAttendee()->getAccessToken(),
+			$event->getRoom()->getToken(),
+			$event->getProperty(),
+			$event->getNewValue(),
+			$event->getCallFlag(),
+			$details,
+		);
+	}
+
+	private function notifyCallEnded(ICloudId $cloudId, Participant $participant, CallEndedEvent|CallEndedForEveryoneEvent $event) {
+		$details = [];
+		if ($event instanceof CallEndedForEveryoneEvent) {
+			$details = [AParticipantModifiedEvent::DETAIL_IN_CALL_END_FOR_EVERYONE => true];
+		}
+
+		return $this->backendNotifier->sendCallEnded(
+			$cloudId->getRemote(),
+			$participant->getAttendee()->getId(),
+			$participant->getAttendee()->getAccessToken(),
+			$event->getRoom()->getToken(),
+			ARoomModifiedEvent::PROPERTY_ACTIVE_SINCE,
+			null,
+			Participant::FLAG_DISCONNECTED,
+			$details,
+		);
+	}
+
+	private function notifyLobbyModified(ICloudId $cloudId, Participant $participant, ALobbyModifiedEvent $event) {
+		return $this->backendNotifier->sendRoomModifiedLobbyUpdate(
+			$cloudId->getRemote(),
+			$participant->getAttendee()->getId(),
+			$participant->getAttendee()->getAccessToken(),
+			$event->getRoom()->getToken(),
+			$event->getProperty(),
+			$event->getNewValue(),
+			$event->getOldValue(),
+			$event->getLobbyTimer(),
+			$event->isTimerReached(),
+		);
+	}
+
+	private function notifyRoomModified(ICloudId $cloudId, Participant $participant, ARoomModifiedEvent $event) {
+		return $this->backendNotifier->sendRoomModifiedUpdate(
+			$cloudId->getRemote(),
+			$participant->getAttendee()->getId(),
+			$participant->getAttendee()->getAccessToken(),
+			$event->getRoom()->getToken(),
+			$event->getProperty(),
+			$event->getNewValue(),
+			$event->getOldValue(),
+		);
+	}
+}
@@ -0,0 +1,260 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1;
+
+use GuzzleHttp\Exception\ClientException;
+use GuzzleHttp\Exception\ServerException;
+use OC\Http\Client\Response;
+use OCA\Talk\AppInfo\Application;
+use OCA\Talk\Config as TalkConfig;
+use OCA\Talk\Exceptions\CannotReachRemoteException;
+use OCA\Talk\Exceptions\RemoteClientException;
+use OCA\Talk\Participant;
+use OCA\Talk\Settings\UserPreference;
+use OCP\AppFramework\Http;
+use OCP\Http\Client\IClientService;
+use OCP\Http\Client\IResponse;
+use OCP\IConfig;
+use OCP\IUserSession;
+use OCP\L10N\IFactory;
+use Psr\Log\LoggerInterface;
+use SensitiveParameter;
+
+class ProxyRequest {
+	public function __construct(
+		protected IConfig $config,
+		protected IClientService $clientService,
+		protected LoggerInterface $logger,
+		protected IFactory $l10nFactory,
+		protected IUserSession $userSession,
+		protected TalkConfig $talkConfig,
+	) {
+	}
+
+	public function overwrittenRemoteTalkHash(string $hash): string {
+		$typingIndicator = $this->config->getUserValue(
+			$this->userSession->getUser()?->getUID(),
+			Application::APP_ID,
+			UserPreference::TYPING_PRIVACY,
+			Participant::PRIVACY_PRIVATE,
+		);
+		return sha1(json_encode([
+			'remoteHash' => $hash,
+			'manipulated' => [
+				'config' => [
+					'chat' => [
+						'read-privacy',
+						'typing-privacy' => $typingIndicator,
+					],
+					'call' => [
+						'blur-virtual-background',
+					],
+					'conversations' => [
+						'list-style',
+					],
+				],
+			]
+		]));
+	}
+
+	/**
+	 * @return Http::STATUS_BAD_REQUEST
+	 */
+	public function logUnexpectedStatusCode(string $method, int $statusCode, string $logDetails = ''): int {
+		if ($this->config->getSystemValueBool('debug')) {
+			$this->logger->error('Unexpected status code ' . $statusCode . ' returned for ' . $method . ($logDetails !== '' ? "\n" . $logDetails : ''));
+		} else {
+			$this->logger->debug('Unexpected status code ' . $statusCode . ' returned for ' . $method . ($logDetails !== '' ? "\n" . $logDetails : ''));
+		}
+		return Http::STATUS_BAD_REQUEST;
+	}
+
+	protected function generateDefaultRequestOptions(
+		?string $cloudId,
+		#[SensitiveParameter]
+		?string $accessToken,
+	): array {
+		$options = [
+			'verify' => !$this->config->getSystemValueBool('sharing.federation.allowSelfSignedCertificates'),
+			'nextcloud' => [
+				'allow_local_address' => $this->config->getSystemValueBool('allow_local_remote_servers'),
+			],
+			'headers' => [
+				'Accept' => 'application/json',
+				'X-Nextcloud-Federation' => 'true',
+				'OCS-APIRequest' => 'true',
+				'Accept-Language' => $this->l10nFactory->getUserLanguage($this->userSession->getUser()),
+			],
+			'timeout' => 5,
+		];
+
+		if ($cloudId !== null && $accessToken !== null) {
+			$options['auth'] = [urlencode($cloudId), $accessToken];
+		}
+
+		return $options;
+	}
+
+	protected function prependProtocolIfNotAvailable(string $url): string {
+		if (!str_starts_with($url, 'http://') && !str_starts_with($url, 'https://')) {
+			$url = 'https://' . $url;
+		}
+		return $url;
+	}
+
+	/**
+	 * @param 'get'|'post'|'put'|'delete' $verb
+	 * @throws CannotReachRemoteException
+	 */
+	protected function request(
+		string $verb,
+		?string $cloudId,
+		#[SensitiveParameter]
+		?string $accessToken,
+		string $url,
+		array $parameters,
+	): IResponse {
+		if (!$this->talkConfig->isFederationEnabled()) {
+			throw new CannotReachRemoteException();
+		}
+
+		$requestOptions = $this->generateDefaultRequestOptions($cloudId, $accessToken);
+		if (!empty($parameters)) {
+			$requestOptions['json'] = $parameters;
+		}
+
+		try {
+			return $this->clientService->newClient()->{$verb}(
+				$this->prependProtocolIfNotAvailable($url),
+				$requestOptions
+			);
+		} catch (ClientException $e) {
+			$status = $e->getResponse()->getStatusCode();
+
+			try {
+				$body = $e->getResponse()->getBody()->getContents();
+				$data = json_decode($body, true, flags: JSON_THROW_ON_ERROR);
+				$e->getResponse()->getBody()->rewind();
+				if (!is_array($data)) {
+					throw new \RuntimeException('JSON response is not an array');
+				}
+			} catch (\Throwable $e) {
+				throw new CannotReachRemoteException('Error parsing JSON response', $e->getCode(), $e);
+			}
+
+			$clientException = new RemoteClientException($e->getMessage(), $status, $e, $data);
+			$this->logger->debug('Client error from remote', ['exception' => $clientException]);
+			return new Response($e->getResponse(), false);
+		} catch (ServerException|\Throwable $e) {
+			$serverException = new CannotReachRemoteException($e->getMessage(), $e->getCode(), $e);
+			$this->logger->error('Could not reach remote', ['exception' => $serverException]);
+			throw $serverException;
+		}
+	}
+
+	/**
+	 * @throws CannotReachRemoteException
+	 */
+	public function get(
+		?string $cloudId,
+		#[SensitiveParameter]
+		?string $accessToken,
+		string $url,
+		array $parameters = [],
+	): IResponse {
+		return $this->request(
+			'get',
+			$cloudId,
+			$accessToken,
+			$url,
+			$parameters,
+		);
+	}
+
+	/**
+	 * @throws CannotReachRemoteException
+	 */
+	public function put(
+		string $cloudId,
+		#[SensitiveParameter]
+		string $accessToken,
+		string $url,
+		array $parameters = [],
+	): IResponse {
+		return $this->request(
+			'put',
+			$cloudId,
+			$accessToken,
+			$url,
+			$parameters,
+		);
+	}
+
+	/**
+	 * @throws CannotReachRemoteException
+	 */
+	public function delete(
+		string $cloudId,
+		#[SensitiveParameter]
+		string $accessToken,
+		string $url,
+		array $parameters = [],
+	): IResponse {
+		return $this->request(
+			'delete',
+			$cloudId,
+			$accessToken,
+			$url,
+			$parameters,
+		);
+	}
+
+	/**
+	 * @throws CannotReachRemoteException
+	 */
+	public function post(
+		string $cloudId,
+		#[SensitiveParameter]
+		string $accessToken,
+		string $url,
+		array $parameters = [],
+	): IResponse {
+		return $this->request(
+			'post',
+			$cloudId,
+			$accessToken,
+			$url,
+			$parameters,
+		);
+	}
+
+	/**
+	 * @param list<int> $allowedStatusCodes
+	 * @throws CannotReachRemoteException
+	 */
+	public function getOCSData(IResponse $response, array $allowedStatusCodes = [Http::STATUS_OK]): array {
+		if (!in_array($response->getStatusCode(), $allowedStatusCodes, true)) {
+			$this->logUnexpectedStatusCode(__METHOD__, $response->getStatusCode());
+		}
+
+		try {
+			$content = $response->getBody();
+			$responseData = json_decode($content, true, flags: JSON_THROW_ON_ERROR);
+			if (!is_array($responseData)) {
+				throw new \RuntimeException('JSON response is not an array');
+			}
+		} catch (\Throwable $e) {
+			$this->logger->error('Error parsing JSON response: ' . ($content ?? 'no-data'), ['exception' => $e]);
+			throw new CannotReachRemoteException('Error parsing JSON response', $e->getCode(), $e);
+		}
+
+		return $responseData['ocs']['data'] ?? [];
+	}
+}
@@ -0,0 +1,259 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Talk\Federation\Proxy\TalkV1;
+
+use OCA\Talk\Model\Attendee;
+use OCA\Talk\ResponseDefinitions;
+use OCA\Talk\Room;
+use OCA\Talk\Service\AvatarService;
+use OCA\Talk\Service\ParticipantService;
+
+/**
+ * @psalm-import-type TalkChatMessageWithParent from ResponseDefinitions
+ * @psalm-import-type TalkPoll from ResponseDefinitions
+ * @psalm-import-type TalkPollDraft from ResponseDefinitions
+ * @psalm-import-type TalkReaction from ResponseDefinitions
+ * @psalm-import-type TalkThreadInfo from ResponseDefinitions
+ */
+class UserConverter {
+	/**
+	 * @var array<string, array<string, array{userId: string, displayName: string}>>
+	 */
+	protected array $participantsPerRoom = [];
+
+	public function __construct(
+		protected ParticipantService $participantService,
+		protected AvatarService $avatarService,
+	) {
+	}
+
+	/**
+	 * @return array{type: string, id: string}
+	 */
+	public function convertTypeAndId(Room $room, string $type, string $id): array {
+		if ($type === Attendee::ACTOR_USERS) {
+			$type = Attendee::ACTOR_FEDERATED_USERS;
+			$id = $this->createCloudIdFromUserIdAndFullServerUrl($id, $room->getRemoteServer());
+		} elseif ($type === Attendee::ACTOR_FEDERATED_USERS) {
+			$localParticipants = $this->getLocalParticipants($room);
+			if (isset($localParticipants[$id])) {
+				$local = $localParticipants[$id];
+
+				$type = Attendee::ACTOR_USERS;
+				$id = $local['userId'];
+			}
+		}
+
+		return ['type' => $type, 'id' => $id];
+	}
+
+	public function convertAttendee(Room $room, array $entry, string $typeField, string $idField, string $displayNameField): array {
+		if (!isset($entry[$typeField])) {
+			return $entry;
+		}
+
+		if ($entry[$typeField] === Attendee::ACTOR_USERS) {
+			$entry[$typeField] = Attendee::ACTOR_FEDERATED_USERS;
+			$entry[$idField] = $this->createCloudIdFromUserIdAndFullServerUrl($entry[$idField], $room->getRemoteServer());
+		} elseif ($entry[$typeField] === Attendee::ACTOR_FEDERATED_USERS) {
+			$localParticipants = $this->getLocalParticipants($room);
+			if (isset($localParticipants[$entry[$idField]])) {
+				$local = $localParticipants[$entry[$idField]];
+
+				$entry[$typeField] = Attendee::ACTOR_USERS;
+				$entry[$idField] = $local['userId'];
+				$entry[$displayNameField] = $local['displayName'];
+			}
+		}
+		return $entry;
+	}
+
+	public function convertAttendees(Room $room, array $entries, string $typeField, string $idField, string $displayNameField): array {
+		return array_map(
+			fn (array $entry): array => $this->convertAttendee($room, $entry, $typeField, $idField, $displayNameField),
+			$entries
+		);
+	}
+
+	protected function convertMessageParameter(Room $room, array $parameter): array {
+		if ($parameter['type'] === 'user') { // RichObjectDefinition, not Attendee::ACTOR_USERS
+			if (!isset($parameter['server'])) {
+				$parameter['server'] = $room->getRemoteServer();
+				if (!isset($parameter['mention-id'])) {
+					$parameter['mention-id'] = $parameter['id'];
+				}
+			} elseif ($parameter['server']) {
+				$localParticipants = $this->getLocalParticipants($room);
+				$cloudId = $this->createCloudIdFromUserIdAndFullServerUrl($parameter['id'], $parameter['server']);
+				if (!isset($parameter['mention-id'])) {
+					$parameter['mention-id'] = 'federated_user/' . $parameter['id'] . '@' . $parameter['server'];
+				}
+				if (isset($localParticipants[$cloudId])) {
+					unset($parameter['server']);
+					$parameter['name'] = $localParticipants[$cloudId]['displayName'];
+				}
+			}
+		} elseif ($parameter['type'] === 'call' && $parameter['id'] === $room->getRemoteToken()) {
+			$parameter['id'] = $room->getToken();
+			$parameter['icon-url'] = $this->avatarService->getAvatarUrl($room);
+			if (!isset($parameter['mention-id'])) {
+				$parameter['mention-id'] = 'all';
+			}
+		} elseif ($parameter['type'] === 'circle') {
+			if (!isset($parameter['mention-id'])) {
+				$parameter['mention-id'] = 'team/' . $parameter['id'];
+			}
+		} elseif ($parameter['type'] === 'user-group') {
+			if (!isset($parameter['mention-id'])) {
+				$parameter['mention-id'] = 'group/' . $parameter['id'];
+			}
+		} elseif ($parameter['type'] === 'email' || $parameter['type'] === 'guest') {
+			if (!isset($parameter['mention-id'])) {
+				$parameter['mention-id'] = $parameter['type'] . '/' . $parameter['id'];
+			}
+		}
+		return $parameter;
+	}
+
+	public function convertMessageParameters(Room $room, array $message): array {
+		$message['messageParameters'] = array_map(
+			fn (array $message): array => $this->convertMessageParameter($room, $message),
+			$message['messageParameters']
+		);
+		return $message;
+	}
+
+	/**
+	 * @param Room $room
+	 * @param TalkChatMessageWithParent $message
+	 * @return TalkChatMessageWithParent
+	 */
+	public function convertMessage(Room $room, array $message): array {
+		$message['token'] = $room->getToken();
+		$message = $this->convertAttendee($room, $message, 'actorType', 'actorId', 'actorDisplayName');
+		$message = $this->convertAttendee($room, $message, 'lastEditActorType', 'lastEditActorId', 'lastEditActorDisplayName');
+		$message = $this->convertMessageParameters($room, $message);
+
+		if (isset($message['parent'])) {
+			$message['parent'] = $this->convertMessage($room, $message['parent']);
+		}
+		return $message;
+	}
+
+	/**
+	 * @param Room $room
+	 * @param TalkChatMessageWithParent[] $messages
+	 * @return TalkChatMessageWithParent[]
+	 */
+	public function convertMessages(Room $room, array $messages): array {
+		return array_map(
+			fn (array $message): array => $this->convertMessage($room, $message),
+			$messages
+		);
+	}
+
+	/**
+	 * @param Room $room
+	 * @param TalkThreadInfo $threadInfo
+	 * @return TalkThreadInfo
+	 */
+	public function convertThreadInfo(Room $room, array $threadInfo): array {
+		$threadInfo['thread']['roomToken'] = $room->getToken();
+		if (isset($threadInfo['first'])) {
+			$threadInfo['first'] = $this->convertMessageParameters($room, $threadInfo['first']);
+		}
+		if (isset($threadInfo['last'])) {
+			$threadInfo['last'] = $this->convertMessageParameters($room, $threadInfo['last']);
+		}
+		return $threadInfo;
+	}
+
+	/**
+	 * @param Room $room
+	 * @param list<TalkThreadInfo> $threadInfos
+	 * @return list<TalkThreadInfo>
+	 */
+	public function convertThreadInfos(Room $room, array $threadInfos): array {
+		return array_map(
+			fn (array $threadInfo): array => $this->convertThreadInfo($room, $threadInfo),
+			$threadInfos
+		);
+	}
+
+	/**
+	 * @template T of TalkPoll|TalkPollDraft
+	 * @param Room $room
+	 * @param TalkPoll|TalkPollDraft $poll
+	 * @psalm-param T $poll
+	 * @return TalkPoll|TalkPollDraft
+	 * @psalm-return T
+	 */
+	public function convertPoll(Room $room, array $poll): array {
+		$poll = $this->convertAttendee($room, $poll, 'actorType', 'actorId', 'actorDisplayName');
+		if (isset($poll['details'])) {
+			$poll['details'] = array_map(
+				fn (array $vote): array => $this->convertAttendee($room, $vote, 'actorType', 'actorId', 'actorDisplayName'),
+				$poll['details']
+			);
+		}
+		return $poll;
+	}
+
+	/**
+	 * @param Room $room
+	 * @param TalkReaction[] $reactions
+	 * @return TalkReaction[]
+	 */
+	protected function convertReactions(Room $room, array $reactions): array {
+		return array_map(
+			fn (array $reaction): array => $this->convertAttendee($room, $reaction, 'actorType', 'actorId', 'actorDisplayName'),
+			$reactions
+		);
+	}
+
+	/**
+	 * @param Room $room
+	 * @param array<string, TalkReaction[]> $reactionsList
+	 * @return array<string, TalkReaction[]>
+	 */
+	public function convertReactionsList(Room $room, array $reactionsList): array {
+		return array_map(
+			fn (array $reactions): array => $this->convertReactions($room, $reactions),
+			$reactionsList
+		);
+	}
+
+	/**
+	 * @return array<string, array{userId: string, displayName: string}>
+	 */
+	protected function getLocalParticipants(Room $room): array {
+		if (array_key_exists($room->getToken(), $this->participantsPerRoom)) {
+			return $this->participantsPerRoom[$room->getToken()];
+		}
+
+		$this->participantsPerRoom[$room->getToken()] = [];
+		$localParticipants = $this->participantService->getActorsByType($room, Attendee::ACTOR_USERS);
+		foreach ($localParticipants as $participant) {
+			$this->participantsPerRoom[$room->getToken()][$participant->getInvitedCloudId()] = [
+				'userId' => $participant->getActorId(),
+				'displayName' => $participant->getDisplayName(),
+			];
+		}
+
+		return $this->participantsPerRoom[$room->getToken()];
+	}
+
+	protected function createCloudIdFromUserIdAndFullServerUrl(string $userId, string $serverUrl): string {
+		if (str_starts_with($serverUrl, 'https://')) {
+			$serverUrl = substr($serverUrl, strlen('https://'));
+		}
+		return $userId . '@' . $serverUrl;
+	}
+}