Implement CloudFederationProvider for Talk

Signed-off-by: Gary Kim <gary@garykim.dev>

14 files changed, 908 insertions, 7 deletions

diff --git a/lib/BackgroundJob/RemoveEmptyRooms.php b/lib/BackgroundJob/RemoveEmptyRooms.php
index af9738809..3c620c171 100644
--- a/lib/BackgroundJob/RemoveEmptyRooms.php
+++ b/lib/BackgroundJob/RemoveEmptyRooms.php
@@ -23,6 +23,7 @@ declare(strict_types=1);
 
 namespace OCA\Talk\BackgroundJob;
 
+use OCA\Talk\Federation\FederationManager;
 use OCA\Talk\Service\ParticipantService;
 use OCP\AppFramework\Utility\ITimeFactory;
 use OCP\BackgroundJob\TimedJob;
@@ -46,6 +47,9 @@ class RemoveEmptyRooms extends TimedJob {
 	/** @var LoggerInterface */
 	protected $logger;
 
+	/** @var FederationManager */
+	protected $federationManager;
+
 	protected $numDeletedRooms = 0;
 
 	public function __construct(ITimeFactory $timeFactory,
@@ -77,7 +81,7 @@ class RemoveEmptyRooms extends TimedJob {
 			return;
 		}
 
-		if ($this->participantService->getNumberOfActors($room) === 0 && $room->getObjectType() !== 'file') {
+		if ($this->participantService->getNumberOfActors($room) === 0 && $room->getObjectType() !== 'file' && $this->federationManager->getNumberOfInvitations($room) === 0) {
 			$room->deleteRoom();
 			$this->numDeletedRooms++;
 		}
diff --git a/lib/Controller/FederationController.php b/lib/Controller/FederationController.php
new file mode 100644
index 000000000..ea951d593
--- /dev/null
+++ b/lib/Controller/FederationController.php
@@ -0,0 +1,87 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2021, Gary Kim <gary@garykim.dev>
+ *
+ * @author Gary Kim <gary@garykim.dev>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Talk\Controller;
+
+use OCA\Talk\AppInfo\Application;
+use OCA\Talk\Exceptions\UnauthorizedException;
+use OCA\Talk\Federation\FederationManager;
+use OCP\AppFramework\Db\MultipleObjectsReturnedException;
+use OCP\AppFramework\Http\DataResponse;
+use OCP\AppFramework\OCSController;
+use OCP\DB\Exception as DBException;
+use OCP\IRequest;
+use OCP\IUser;
+use OCP\IUserSession;
+
+class FederationController extends OCSController {
+	/** @var FederationManager */
+	private $federationManager;
+
+	/** @var IUserSession */
+	private $userSession;
+
+	public function __construct(IRequest $request, FederationManager $federationManager, IUserSession $userSession) {
+		parent::__construct(Application::APP_ID, $request);
+		$this->federationManager = $federationManager;
+		$this->userSession = $userSession;
+	}
+
+	/**
+	 * @NoAdminRequired
+	 *
+	 * @param int $id
+	 * @return DataResponse
+	 * @throws UnauthorizedException
+	 * @throws DBException
+	 * @throws MultipleObjectsReturnedException
+	 */
+	public function acceptShare(int $id): DataResponse {
+		$user = $this->userSession->getUser();
+		if (!$user instanceof IUser) {
+			throw new UnauthorizedException();
+		}
+		$this->federationManager->acceptRemoteRoomShare($user, $id);
+		return new DataResponse();
+	}
+
+	/**
+	 * @NoAdminRequired
+	 *
+	 * @param int $id
+	 * @return DataResponse
+	 * @throws UnauthorizedException
+	 * @throws DBException
+	 * @throws MultipleObjectsReturnedException
+	 */
+	public function rejectShare(int $id): DataResponse {
+		$user = $this->userSession->getUser();
+		if (!$user instanceof IUser) {
+			throw new UnauthorizedException();
+		}
+		$this->federationManager->rejectRemoteRoomShare($user, $id);
+		return new DataResponse();
+	}
+}
diff --git a/lib/Federation/CloudFederationProviderTalk.php b/lib/Federation/CloudFederationProviderTalk.php
new file mode 100644
index 000000000..9cf401afd
--- /dev/null
+++ b/lib/Federation/CloudFederationProviderTalk.php
@@ -0,0 +1,262 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2021 Gary Kim <gary@garykim.dev>
+ *
+ * @author Gary Kim <gary@garykim.dev>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Talk\Federation;
+
+use Exception;
+use OC\AppFramework\Http;
+use OC\HintException;
+use OCA\FederatedFileSharing\AddressHandler;
+use OCA\Talk\AppInfo\Application;
+use OCA\Talk\Manager;
+use OCA\Talk\Model\Attendee;
+use OCA\Talk\Model\AttendeeMapper;
+use OCA\Talk\Participant;
+use OCA\Talk\Service\ParticipantService;
+use OCP\DB\Exception as DBException;
+use OCP\Federation\Exceptions\ActionNotSupportedException;
+use OCP\Federation\Exceptions\AuthenticationFailedException;
+use OCP\Federation\Exceptions\BadRequestException;
+use OCP\Federation\Exceptions\ProviderCouldNotAddShareException;
+use OCP\Federation\ICloudFederationProvider;
+use OCP\Federation\ICloudFederationShare;
+use OCP\IURLGenerator;
+use OCP\IUser;
+use OCP\IUserManager;
+use OCP\Notification\IManager as INotificationManager;
+use OCP\Share\Exceptions\ShareNotFound;
+
+class CloudFederationProviderTalk implements ICloudFederationProvider {
+
+	/** @var IUserManager */
+	private $userManager;
+
+	/** @var AddressHandler */
+	private $addressHandler;
+
+	/** @var FederationManager */
+	private $federationManager;
+
+	/** @var INotificationManager */
+	private $notificationManager;
+
+	/** @var IURLGenerator */
+	private $urlGenerator;
+
+	/** @var ParticipantService  */
+	private $participantService;
+
+	/** @var AttendeeMapper  */
+	private $attendeeMapper;
+
+	/** @var Manager  */
+	private $manager;
+
+	public function __construct(
+		IUserManager $userManager,
+		AddressHandler $addressHandler,
+		FederationManager $federationManager,
+		INotificationManager $notificationManager,
+		IURLGenerator $urlGenerator,
+		ParticipantService $participantService,
+		AttendeeMapper $attendeeMapper,
+		Manager $manager
+	) {
+		$this->userManager = $userManager;
+		$this->addressHandler = $addressHandler;
+		$this->federationManager = $federationManager;
+		$this->notificationManager = $notificationManager;
+		$this->urlGenerator = $urlGenerator;
+		$this->participantService = $participantService;
+		$this->attendeeMapper = $attendeeMapper;
+		$this->manager = $manager;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function getShareType(): string {
+		return 'talk-room';
+	}
+
+	/**
+	 * @inheritDoc
+	 * @throws HintException
+	 * @throws DBException
+	 */
+	public function shareReceived(ICloudFederationShare $share): string {
+		if (!$this->federationManager->isEnabled()) {
+			throw new ProviderCouldNotAddShareException('Server does not support talk federation', '', Http::STATUS_SERVICE_UNAVAILABLE);
+		}
+		if ($share->getShareType() !== 'user') {
+			throw new ProviderCouldNotAddShareException('support for sharing with non-users not implemented yet', '', Http::STATUS_NOT_IMPLEMENTED);
+			// TODO: Implement group shares
+		}
+
+		if (!is_numeric($share->getShareType())) {
+			throw new ProviderCouldNotAddShareException('RoomType is not a number', '', Http::STATUS_BAD_REQUEST);
+		}
+
+		$shareSecret = $share->getShareSecret();
+		$shareWith = $share->getShareWith();
+		$roomToken = $share->getProviderId();
+		$roomName = $share->getResourceName();
+		$roomType = (int) $share->getShareType();
+		$sharedBy = $share->getSharedByDisplayName();
+		$sharedByFederatedId = $share->getSharedBy();
+		$owner = $share->getOwnerDisplayName();
+		$ownerFederatedId = $share->getOwner();
+		[, $remote] = $this->addressHandler->splitUserRemote($ownerFederatedId);
+
+		// if no explicit information about the person who created the share was send
+		// we assume that the share comes from the owner
+		if ($sharedByFederatedId === null) {
+			$sharedBy = $owner;
+			$sharedByFederatedId = $ownerFederatedId;
+		}
+
+		if ($remote && $shareSecret && $shareWith && $roomToken && $roomName && $owner) {
+			$shareWith = $this->userManager->get($shareWith);
+			if ($shareWith === null) {
+				throw new ProviderCouldNotAddShareException('User does not exist', '',Http::STATUS_BAD_REQUEST);
+			}
+
+			$shareId = (string) $this->federationManager->addRemoteRoom($shareWith, $roomType, $roomName, $roomToken, $remote, $shareSecret);
+
+			$this->notifyAboutNewShare($shareWith, $shareId, $sharedByFederatedId, $sharedBy, $roomName, $roomToken, $remote);
+			return $shareId;
+		}
+		throw new ProviderCouldNotAddShareException('required request data not found', '', Http::STATUS_BAD_REQUEST);
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function notificationReceived($notificationType, $providerId, array $notification): array {
+		if (!is_numeric($providerId)) {
+			throw new BadRequestException(['providerId']);
+		}
+		switch ($notificationType) {
+			case 'SHARE_ACCEPTED':
+				return $this->shareAccepted((int) $providerId, $notification);
+			case 'SHARE_DECLINED':
+				return $this->shareDeclined((int) $providerId, $notification);
+			case 'SHARE_UNSHARED':
+				return []; // TODO: Implement
+			case 'REQUEST_RESHARE':
+				return []; // TODO: Implement
+			case 'RESHARE_UNDO':
+				return []; // TODO: Implement
+			case 'RESHARE_CHANGE_PERMISSION':
+				return []; // TODO: Implement
+		}
+		// TODO: Implement notificationReceived() method.
+	}
+
+	/**
+	 * @throws ActionNotSupportedException
+	 * @throws ShareNotFound
+	 * @throws AuthenticationFailedException
+	 */
+	private function shareAccepted(int $id, array $notification): array {
+		$attendee = $this->getAttendeeAndValidate($id, $notification['sharedSecret']);
+
+		// TODO: Add activity for share accepted
+
+		return [];
+	}
+
+	/**
+	 * @throws ActionNotSupportedException
+	 * @throws ShareNotFound
+	 * @throws AuthenticationFailedException
+	 */
+	private function shareDeclined(int $id, array $notification): array {
+		$attendee = $this->getAttendeeAndValidate($id, $notification['sharedSecret']);
+
+		$room = $this->manager->getRoomById($attendee->getRoomId());
+		$participant = new Participant($room, $attendee, null);
+		$this->participantService->removeAttendee($room, $participant, 'Left Room');
+		return [];
+	}
+
+	/**
+	 * @throws AuthenticationFailedException
+	 * @throws ActionNotSupportedException
+	 * @throws ShareNotFound
+	 */
+	private function getAttendeeAndValidate(int $id, string $sharedSecret): Attendee {
+		if (!$this->federationManager->isEnabled()) {
+			throw new ActionNotSupportedException('Server does not support Talk federation');
+		}
+
+		try {
+			$attendee = $this->attendeeMapper->getById($id);
+		} catch (Exception $ex) {
+			throw new ShareNotFound();
+		}
+		if ($attendee->getActorType() !== Attendee::ACTOR_FEDERATED_REMOTE_USER) {
+			throw new ShareNotFound();
+		}
+		if ($attendee->getAccessToken() !== $sharedSecret) {
+			throw new AuthenticationFailedException();
+		}
+		return $attendee;
+	}
+
+	private function notifyAboutNewShare(IUser $shareWith, string $shareId, string $sharedByFederatedId, string $sharedByName, string $roomName, string $roomToken, string $serverUrl) {
+		$notification = $this->notificationManager->createNotification();
+		$notification->setApp(Application::APP_ID)
+			->setUser($shareWith->getUID())
+			->setDateTime(new \DateTime())
+			->setObject('remote_talk_share', $shareId)
+			->setSubject('remote_talk_share', [
+				'sharedByDisplayName' => $sharedByName,
+				'sharedByFederatedId' => $sharedByFederatedId,
+				'roomName' => $roomName,
+				'serverUrl' => $serverUrl,
+				'roomToken' => $roomToken,
+			]);
+
+		$declineAction = $notification->createAction();
+		$declineAction->setLabel('decline')
+			->setLink($this->urlGenerator->linkToOCSRouteAbsolute('spreed.Federation.rejectShare', ['id' => $shareId]), 'DELETE');
+		$notification->addAction($declineAction);
+
+		$acceptAction = $notification->createAction();
+		$acceptAction->setLabel('accept')
+			->setLink($this->urlGenerator->linkToOCSRouteAbsolute('spreed.Federation.acceptShare', ['id' => $shareId]), 'POST');
+		$notification->addAction($acceptAction);
+
+		$this->notificationManager->notify($notification);
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function getSupportedShareTypes() {
+		return ['user'];
+	}
+}
diff --git a/lib/Federation/FederationManager.php b/lib/Federation/FederationManager.php
new file mode 100644
index 000000000..58336478c
--- /dev/null
+++ b/lib/Federation/FederationManager.php
@@ -0,0 +1,156 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2021 Gary Kim <gary@garykim.dev>
+ *
+ * @author Gary Kim <gary@garykim.dev>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Talk\Federation;
+
+use OCA\Talk\Exceptions\RoomNotFoundException;
+use OCA\Talk\Exceptions\UnauthorizedException;
+use OCA\Talk\Manager;
+use OCA\Talk\Model\Attendee;
+use OCA\Talk\Model\Invitation;
+use OCA\Talk\Model\InvitationMapper;
+use OCA\Talk\Room;
+use OCA\Talk\Service\ParticipantService;
+use OCP\AppFramework\Db\MultipleObjectsReturnedException;
+use OCP\DB\Exception as DBException;
+use OCP\IConfig;
+use OCP\IUser;
+
+/**
+ * Class FederationManager
+ *
+ * @package OCA\Talk\Federation
+ *
+ * FederationManager handles incoming federated rooms
+ */
+class FederationManager {
+	/** @var IConfig */
+	private $config;
+
+	/** @var Manager */
+	private $manager;
+
+	/** @var ParticipantService */
+	private $participantService;
+
+	/** @var InvitationMapper */
+	private $invitationMapper;
+
+	public function __construct(
+		IConfig $config,
+		Manager $manager,
+		ParticipantService $participantService,
+		InvitationMapper $invitationMapper
+	) {
+		$this->config = $config;
+		$this->manager = $manager;
+		$this->participantService = $participantService;
+		$this->invitationMapper = $invitationMapper;
+	}
+
+	/**
+	 * Determine if Talk federation is enabled on this instance
+	 * @return bool
+	 */
+	public function isEnabled(): bool {
+		// TODO: Set to default true once implementation is complete
+		return $this->config->getSystemValueBool('talk_federation_enabled', false);
+	}
+
+	/**
+	 * @param IUser $user
+	 * @param int $roomType
+	 * @param string $roomName
+	 * @param string $roomToken
+	 * @param string $remoteUrl
+	 * @param string $sharedSecret
+	 * @return int share id for this specific remote room share
+	 * @throws DBException
+	 */
+	public function addRemoteRoom(IUser $user, int $roomType, string $roomName, string $roomToken, string $remoteUrl, string $sharedSecret): int {
+		try {
+			$room = $this->manager->getRoomByToken($roomToken, null, $remoteUrl);
+		} catch (RoomNotFoundException $ex) {
+			$room = $this->manager->createRemoteRoom($roomType, $roomName, $roomToken, $remoteUrl);
+		}
+		$invitation = new Invitation();
+		$invitation->setUserId($user->getUID());
+		$invitation->setRoomId($room->getId());
+		$invitation->setAccessToken($sharedSecret);
+		$invitation = $this->invitationMapper->insert($invitation);
+
+		return $invitation->getId();
+	}
+
+	/**
+	 * @throws DBException
+	 * @throws UnauthorizedException
+	 * @throws MultipleObjectsReturnedException
+	 */
+	public function acceptRemoteRoomShare(IUser $user, int $shareId) {
+		$invitation = $this->invitationMapper->getInvitationById($shareId);
+		if ($invitation->getUserId() !== $user->getUID()) {
+			throw new UnauthorizedException('invitation is for a different user');
+		}
+
+		// Add user to the room
+		$room = $this->manager->getRoomById($invitation->getRoomId());
+		$participant = [
+			[
+				'actorType' => Attendee::ACTOR_USERS,
+				'actorId' => $user->getUID(),
+				'displayName' => $user->getDisplayName(),
+				'accessToken' => $invitation->getAccessToken(),
+			]
+		];
+		$this->participantService->addUsers($room, $participant);
+
+		$this->invitationMapper->delete($invitation);
+
+		// TODO: Send SHARE_ACCEPTED notification
+	}
+
+	/**
+	 * @throws DBException
+	 * @throws UnauthorizedException
+	 * @throws MultipleObjectsReturnedException
+	 */
+	public function rejectRemoteRoomShare(IUser $user, int $shareId) {
+		$invitation = $this->invitationMapper->getInvitationById($shareId);
+		if ($invitation->getUserId() !== $user->getUID()) {
+			throw new UnauthorizedException('invitation is for a different user');
+		}
+		$this->invitationMapper->delete($invitation);
+
+		// TODO: Send SHARE_DECLINED notification
+	}
+
+	/**
+	 * @throws DBException
+	 */
+	public function getNumberOfInvitations(Room $room): int {
+		return $this->invitationMapper->countInvitationsForRoom($room);
+	}
+}
diff --git a/lib/Manager.php b/lib/Manager.php
index aeb52b200..044c6d3e3 100644
--- a/lib/Manager.php
+++ b/lib/Manager.php
@@ -37,6 +37,7 @@ use OCP\AppFramework\Utility\ITimeFactory;
 use OCP\Comments\IComment;
 use OCP\Comments\ICommentsManager;
 use OCP\Comments\NotFoundException;
+use OCP\DB\Exception as DBException;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\EventDispatcher\IEventDispatcher;
 use OCP\ICache;
@@ -185,6 +186,7 @@ class Manager {
 			(string) $row['name'],
 			(string) $row['description'],
 			(string) $row['password'],
+			(string) $row['server_url'],
 			(int) $row['active_guests'],
 			(int) $row['call_flag'],
 			$activeSince,
@@ -628,7 +630,7 @@ class Manager {
 	 * @return Room
 	 * @throws RoomNotFoundException
 	 */
-	public function getRoomByActor(string $token, string $actorType, string $actorId, ?string $sessionId = null): Room {
+	public function getRoomByActor(string $token, string $actorType, string $actorId, ?string $sessionId = null, ?string $server_url = null): Room {
 		$query = $this->db->getQueryBuilder();
 		$helper = new SelectHelper();
 		$helper->selectRoomsTable($query);
@@ -641,6 +643,12 @@ class Manager {
 			))
 			->where($query->expr()->eq('r.token', $query->createNamedParameter($token)));
 
+		if ($server_url === null) {
+			$query->andWhere($query->expr()->isNull('r.server_url'));
+		} else {
+			$query->andWhere($query->expr()->eq('r.server_url', $query->createNamedParameter($server_url)));
+		}
+
 		if ($sessionId !== null) {
 			$helper->selectSessionsTable($query);
 			$query->leftJoin('a', 'talk_sessions', 's', $query->expr()->andX(
@@ -676,10 +684,10 @@ class Manager {
 	 * @return Room
 	 * @throws RoomNotFoundException
 	 */
-	public function getRoomByToken(string $token, ?string $preloadUserId = null): Room {
+	public function getRoomByToken(string $token, ?string $preloadUserId = null, ?string $serverUrl = null): Room {
 		$preloadUserId = $preloadUserId === '' ? null : $preloadUserId;
 		if ($preloadUserId !== null) {
-			return $this->getRoomByActor($token, Attendee::ACTOR_USERS, $preloadUserId);
+			return $this->getRoomByActor($token, Attendee::ACTOR_USERS, $preloadUserId, null, $serverUrl);
 		}
 
 		$query = $this->db->getQueryBuilder();
@@ -688,6 +696,13 @@ class Manager {
 		$query->from('talk_rooms', 'r')
 			->where($query->expr()->eq('r.token', $query->createNamedParameter($token)));
 
+		if ($serverUrl === null) {
+			$query->andWhere($query->expr()->isNull('r.server_url'));
+		} else {
+			$query->andWhere($query->expr()->eq('r.server_url', $query->createNamedParameter($serverUrl)));
+		}
+
+
 		$result = $query->execute();
 		$row = $result->fetch();
 		$result->closeCursor();
@@ -908,6 +923,29 @@ class Manager {
 		return $room;
 	}
 
+	/**
+	 * @param int $type
+	 * @param string $name
+	 * @return Room
+	 * @throws DBException
+	 */
+	public function createRemoteRoom(int $type, string $name, string $token, string $serverUrl): Room {
+		$qb = $this->db->getQueryBuilder();
+
+		$qb->insert('talk_rooms')
+			->values([
+				'name' => $qb->createNamedParameter($name),
+				'type' => $qb->createNamedParameter($type, IQueryBuilder::PARAM_INT),
+				'token' => $qb->createNamedParameter($token),
+				'server_url' => $qb->createNamedParameter($serverUrl),
+			]);
+
+		$qb->executeStatement();
+		$roomId = $qb->getLastInsertId();
+
+		return $this->getRoomById($roomId);
+	}
+
 	public function resolveRoomDisplayName(Room $room, string $userId): string {
 		if ($room->getObjectType() === 'share:password') {
 			return $this->l->t('Password request: %s', [$room->getName()]);
diff --git a/lib/Migration/Version13000Date20210625232111.php b/lib/Migration/Version13000Date20210625232111.php
new file mode 100644
index 000000000..437a785d7
--- /dev/null
+++ b/lib/Migration/Version13000Date20210625232111.php
@@ -0,0 +1,88 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2021 Gary Kim <gary@garykim.dev>
+ *
+ * @author Gary Kim <gary@garykim.dev>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Talk\Migration;
+
+use Closure;
+use Doctrine\DBAL\Schema\SchemaException;
+use Doctrine\DBAL\Types\Types;
+use OCP\DB\ISchemaWrapper;
+use OCP\Migration\IOutput;
+use OCP\Migration\SimpleMigrationStep;
+
+class Version13000Date20210625232111 extends SimpleMigrationStep {
+	/**
+	 * @param IOutput $output
+	 * @param Closure $schemaClosure The `\Closure` returns a `ISchemaWrapper`
+	 * @param array $options
+	 * @return null|ISchemaWrapper
+	 * @throws SchemaException
+	 */
+	public function changeSchema(IOutput $output, Closure $schemaClosure, array $options): ?ISchemaWrapper {
+		/** @var ISchemaWrapper $schema */
+		$schema = $schemaClosure();
+
+		if ($schema->hasTable('talk_attendees')) {
+			$table = $schema->getTable('talk_attendees');
+			if (!$table->hasColumn('access_token')) {
+				$table->addColumn('access_token', Types::STRING, [
+					'notnull' => false,
+					'default' => null,
+				]);
+			}
+		}
+
+		if ($schema->hasTable('talk_rooms')) {
+			$table = $schema->getTable('talk_rooms');
+			if (!$table->hasColumn('server_url')) {
+				$table->addColumn('server_url', Types::STRING, [
+					'notnull' => false,
+					'default' => null,
+				]);
+			}
+		}
+
+		$table = $schema->createTable('talk_invitations');
+		$table->addColumn('id', Types::BIGINT, [
+			'autoincrement' => true,
+			'notnull' => true,
+		]);
+		$table->addColumn('room_id', Types::BIGINT, [
+			'notnull' => true,
+			'unsigned' => true,
+		]);
+		$table->addColumn('user_id', Types::STRING, [
+			'notnull' => true,
+			'length' => 255,
+		]);
+		$table->addColumn('access_token', Types::STRING, [
+			'notnull' => true,
+		]);
+
+		$table->setPrimaryKey(['id']);
+
+		return $schema;
+	}
+}
diff --git a/lib/Model/Attendee.php b/lib/Model/Attendee.php
index 6f7b083a5..0591d1dac 100644
--- a/lib/Model/Attendee.php
+++ b/lib/Model/Attendee.php
@@ -27,7 +27,7 @@ use OCP\AppFramework\Db\Entity;
 
 /**
  * @method void setRoomId(int $roomId)
- * @method string getRoomId()
+ * @method int getRoomId()
  * @method void setActorType(string $actorType)
  * @method string getActorType()
  * @method void setActorId(string $actorId)
@@ -51,6 +51,8 @@ use OCP\AppFramework\Db\Entity;
  * @method int getReadPrivacy()
  * @method void setPublishingPermissions(int $publishingPermissions)
  * @method int getPublishingPermissions()
+ * @method void setAccessToken(string $accessToken)
+ * @method null|string getAccessToken()
  */
 class Attendee extends Entity {
 	public const ACTOR_USERS = 'users';
@@ -59,6 +61,7 @@ class Attendee extends Entity {
 	public const ACTOR_EMAILS = 'emails';
 	public const ACTOR_CIRCLES = 'circles';
 	public const ACTOR_BRIDGED = 'bridged';
+	public const ACTOR_FEDERATED_REMOTE_USER = 'federated_remote';
 
 	public const PUBLISHING_PERMISSIONS_NONE = 0;
 	public const PUBLISHING_PERMISSIONS_AUDIO = 1;
@@ -105,6 +108,9 @@ class Attendee extends Entity {
 	/** @var int */
 	protected $publishingPermissions;
 
+	/** @var string */
+	protected $accessToken;
+
 	public function __construct() {
 		$this->addType('roomId', 'int');
 		$this->addType('actorType', 'string');
@@ -119,6 +125,7 @@ class Attendee extends Entity {
 		$this->addType('lastMentionMessage', 'int');
 		$this->addType('readPrivacy', 'int');
 		$this->addType('publishingPermissions', 'int');
+		$this->addType('accessToken', 'string');
 	}
 
 	public function getDisplayName(): string {
@@ -144,6 +151,7 @@ class Attendee extends Entity {
 			'last_mention_message' => $this->getLastMentionMessage(),
 			'read_privacy' => $this->getReadPrivacy(),
 			'publishing_permissions' => $this->getPublishingPermissions(),
+			'access_token' => $this->getAccessToken(),
 		];
 	}
 }
diff --git a/lib/Model/AttendeeMapper.php b/lib/Model/AttendeeMapper.php
index 3e8586389..cbf6f0393 100644
--- a/lib/Model/AttendeeMapper.php
+++ b/lib/Model/AttendeeMapper.php
@@ -23,12 +23,17 @@ declare(strict_types=1);
 
 namespace OCA\Talk\Model;
 
+use OCP\AppFramework\Db\DoesNotExistException;
+use OCP\AppFramework\Db\MultipleObjectsReturnedException;
 use OCP\AppFramework\Db\QBMapper;
+use OCP\DB\Exception as DBException;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\IDBConnection;
 
 /**
  * @method Attendee mapRowToEntity(array $row)
+ * @method Attendee findEntity(IQueryBuilder $query)
+ * @method Attendee[] findEntities(IQueryBuilder $query)
  */
 class AttendeeMapper extends QBMapper {
 
@@ -44,7 +49,7 @@ class AttendeeMapper extends QBMapper {
 	 * @param string $actorType
 	 * @param string $actorId
 	 * @return Attendee
-	 * @throws \OCP\AppFramework\Db\DoesNotExistException
+	 * @throws DoesNotExistException
 	 */
 	public function findByActor(int $roomId, string $actorType, string $actorId): Attendee {
 		$query = $this->db->getQueryBuilder();
@@ -58,6 +63,22 @@ class AttendeeMapper extends QBMapper {
 	}
 
 	/**
+	 * @param int $id
+	 * @return Attendee
+	 * @throws DoesNotExistException
+	 * @throws MultipleObjectsReturnedException
+	 * @throws DBException
+	 */
+	public function getById(int $id): Attendee {
+		$query = $this->db->getQueryBuilder();
+		$query->select('*')
+			->from($this->getTableName())
+			->where($query->expr()->eq('id', $query->createNamedParameter($id)));
+
+		return $this->findEntity($query);
+	}
+
+	/**
 	 * @param int $roomId
 	 * @param string $actorType
 	 * @param int|null $lastJoinedCall
@@ -153,6 +174,7 @@ class AttendeeMapper extends QBMapper {
 			'last_mention_message' => (int) $row['last_mention_message'],
 			'read_privacy' => (int) $row['read_privacy'],
 			'publishing_permissions' => (int) $row['publishing_permissions'],
+			'access_token' => (string) $row['access_token'],
 		]);
 	}
 }
diff --git a/lib/Model/Invitation.php b/lib/Model/Invitation.php
new file mode 100644
index 000000000..cf2a591e0
--- /dev/null
+++ b/lib/Model/Invitation.php
@@ -0,0 +1,66 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2021 Gary Kim <gary@garykim.dev>
+ *
+ * @author Gary Kim <gary@garykim.dev>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Talk\Model;
+
+use OCP\AppFramework\Db\Entity;
+
+/**
+ * Class Invitation
+ *
+ * @package OCA\Talk\Model
+ *
+ * @method void setRoomId(int $roomId)
+ * @method int getRoomId()
+ * @method void setUserId(string $userId)
+ * @method string getUserId()
+ * @method void setAccessToken(string $accessToken)
+ * @method string getAccessToken()
+ */
+class Invitation extends Entity {
+	/** @var int */
+	protected $roomId;
+
+	/** @var string */
+	protected $userId;
+
+	/** @var string */
+	protected $accessToken;
+
+	public function __construct() {
+		$this->addType('roomId', 'int');
+		$this->addType('userId', 'string');
+		$this->addType('accessToken', 'string');
+	}
+
+	public function asArray(): array {
+		return [
+			'id' => $this->getId(),
+			'room_id' => $this->getRoomId(),
+			'user_id' => $this->getUserId(),
+			'access_token' => $this->getAccessToken(),
+		];
+	}
+}
diff --git a/lib/Model/InvitationMapper.php b/lib/Model/InvitationMapper.php
new file mode 100644
index 000000000..2a453a2a0
--- /dev/null
+++ b/lib/Model/InvitationMapper.php
@@ -0,0 +1,105 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2021 Gary Kim <gary@garykim.dev>
+ *
+ * @author Gary Kim <gary@garykim.dev>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Talk\Model;
+
+use OCA\Talk\Room;
+use OCP\AppFramework\Db\DoesNotExistException;
+use OCP\AppFramework\Db\MultipleObjectsReturnedException;
+use OCP\AppFramework\Db\QBMapper;
+use OCP\DB\Exception as DBException;
+use OCP\DB\QueryBuilder\IQueryBuilder;
+use OCP\IDBConnection;
+
+/**
+ * Class InvitationMapper
+ *
+ * @package OCA\Talk\Model
+ *
+ * @method Invitation mapRowToEntity(array $row)
+ * @method Invitation findEntity(IQueryBuilder $query)
+ * @method Invitation[] findEntities(IQueryBuilder $query)
+ */
+class InvitationMapper extends QBMapper {
+	public function __construct(IDBConnection $db) {
+		parent::__construct($db, 'talk_invitations', Invitation::class);
+	}
+
+	/**
+	 * @throws DBException
+	 * @throws MultipleObjectsReturnedException
+	 * @throws DoesNotExistException
+	 */
+	public function getInvitationById(int $id): Invitation {
+		$qb = $this->db->getQueryBuilder();
+
+		$qb->select('*')
+			->from($this->getTableName())
+			->where($qb->expr()->eq('id', $qb->createNamedParameter($id)));
+
+		return $this->findEntity($qb);
+	}
+
+	/**
+	 * @param Room $room
+	 * @return Invitation[]
+	 * @throws DBException
+	 */
+	public function getInvitationsForRoom(Room $room): array {
+		$qb = $this->db->getQueryBuilder();
+
+		$qb->select('*')
+			->from($this->getTableName())
+			->where($qb->expr()->eq('room_id', $qb->createNamedParameter($room->getId())));
+
+		return $this->findEntities($qb);
+	}
+
+	/**
+	 * @throws DBException
+	 */
+	public function countInvitationsForRoom(Room $room): int {
+		$qb = $this->db->getQueryBuilder();
+
+		$qb->select($qb->func()->count('*', 'num_invitations'))
+			->from($this->getTableName())
+			->where($qb->expr()->eq('room_id', $qb->createNamedParameter($room->getId())));
+
+		$result = $qb->executeQuery();
+		$row = $result->fetch();
+		$result->closeCursor();
+
+		return (int) ($row['num_invitations' ?? 0]);
+	}
+
+	public function createInvitationFromRow(array $row): Invitation {
+		return $this->mapRowToEntity([
+			'id' => $row['id'],
+			'room_id' => $row['room_id'],
+			'user_id' => $row['user_id'],
+			'access_token' => $row['access_token'],
+		]);
+	}
+}
diff --git a/lib/Model/SelectHelper.php b/lib/Model/SelectHelper.php
index dfcab988a..0730329fd 100644
--- a/lib/Model/SelectHelper.php
+++ b/lib/Model/SelectHelper.php
@@ -49,6 +49,7 @@ class SelectHelper {
 			->addSelect($alias . 'object_type')
 			->addSelect($alias . 'object_id')
 			->addSelect($alias . 'listable')
+			->addSelect($alias . 'server_url')
 			->selectAlias($alias . 'id', 'r_id');
 	}
 
@@ -70,6 +71,7 @@ class SelectHelper {
 			->addSelect($alias . 'last_mention_message')
 			->addSelect($alias . 'read_privacy')
 			->addSelect($alias . 'publishing_permissions')
+			->addSelect($alias . 'access_token')
 			->selectAlias($alias . 'id', 'a_id');
 	}
 
diff --git a/lib/Notification/Notifier.php b/lib/Notification/Notifier.php
index eeb657bdf..ab81dcf0f 100644
--- a/lib/Notification/Notifier.php
+++ b/lib/Notification/Notifier.php
@@ -23,6 +23,8 @@ declare(strict_types=1);
 
 namespace OCA\Talk\Notification;
 
+use OC\HintException;
+use OCA\FederatedFileSharing\AddressHandler;
 use OCA\Talk\Chat\CommentsManager;
 use OCA\Talk\Chat\MessageParser;
 use OCA\Talk\Config;
@@ -77,6 +79,8 @@ class Notifier implements INotifier {
 	protected $messageParser;
 	/** @var Definitions */
 	protected $definitions;
+	/** @var AddressHandler */
+	protected $addressHandler;
 
 	/** @var Room[] */
 	protected $rooms = [];
@@ -94,7 +98,8 @@ class Notifier implements INotifier {
 								INotificationManager $notificationManager,
 								CommentsManager $commentManager,
 								MessageParser $messageParser,
-								Definitions $definitions) {
+								Definitions $definitions,
+								AddressHandler $addressHandler) {
 		$this->lFactory = $lFactory;
 		$this->url = $url;
 		$this->config = $config;
@@ -107,6 +112,7 @@ class Notifier implements INotifier {
 		$this->commentManager = $commentManager;
 		$this->messageParser = $messageParser;
 		$this->definitions = $definitions;
+		$this->addressHandler = $addressHandler;
 	}
 
 	/**
@@ -258,6 +264,10 @@ class Notifier implements INotifier {
 			return $this->parseChatMessage($notification, $room, $participant, $l);
 		}
 
+		if ($subject === 'remote_talk_share') {
+			return $this->parseRemoteInvitationMessage($notification, $l);
+		}
+
 		$this->notificationManager->markProcessed($notification);
 		throw new \InvalidArgumentException('Unknown subject');
 	}
@@ -271,6 +281,44 @@ class Notifier implements INotifier {
 	}
 
 	/**
+	 * @throws HintException
+	 */
+	protected function parseRemoteInvitationMessage(INotification $notification, IL10N $l): INotification {
+		$subjectParameters = $notification->getSubjectParameters();
+
+		[$sharedById, $sharedByServer] = $this->addressHandler->splitUserRemote($subjectParameters['sharedByFederatedId']);
+
+		$message = $l->t('{user1} shared room {roomName} on {remoteServer} with you');
+		$parsedMessage = $l->t('{user1} shared room {roomName} on {remoteServer} with you', [
+			'user1' => $subjectParameters['sharedByFederatedId'],
+			'roomName' => $subjectParameters['roomName'],
+			'remoteServer' => $subjectParameters['serverUrl'],
+		]);
+
+		$notification->setParsedMessage($parsedMessage);
+		$notification->setRichMessage($message, [
+			'user1' => [
+				'type' => 'user',
+				'id' => $sharedById,
+				'name' => $subjectParameters['sharedByDisplayName'],
+				'server' => $sharedByServer,
+			],
+			'roomName' => [
+				'type' => 'highlight',
+				'id' => $subjectParameters['serverUrl'] . '::' . $subjectParameters['roomToken'],
+				'name' => $subjectParameters['roomName'],
+			],
+			'remoteServer' => [
+				'type' => 'highlight',
+				'id' => $subjectParameters['serverUrl'],
+				'name' => $subjectParameters['serverUrl'],
+			]
+		]);
+
+		return $notification;
+	}
+
+	/**
 	 * @param INotification $notification
 	 * @param Room $room
 	 * @param Participant $participant
diff --git a/lib/Room.php b/lib/Room.php
index d52fd2200..035072261 100644
--- a/lib/Room.php
+++ b/lib/Room.php
@@ -180,6 +180,8 @@ class Room {
 	private $description;
 	/** @var string */
 	private $password;
+	/** @var string */
+	private $serverUrl;
 	/** @var int */
 	private $activeGuests;
 	/** @var int */
@@ -218,6 +220,7 @@ class Room {
 								string $name,
 								string $description,
 								string $password,
+								string $serverUrl,
 								int $activeGuests,
 								int $callFlag,
 								?\DateTime $activeSince,
@@ -243,6 +246,7 @@ class Room {
 		$this->name = $name;
 		$this->description = $description;
 		$this->password = $password;
+		$this->serverUrl = $serverUrl;
 		$this->activeGuests = $activeGuests;
 		$this->callFlag = $callFlag;
 		$this->activeSince = $activeSince;
@@ -377,6 +381,14 @@ class Room {
 		return $this->password;
 	}
 
+	public function getServerUrl(): string {
+		return $this->serverUrl;
+	}
+
+	public function isFederatedRemoteRoom(): bool {
+		return $this->serverUrl !== '';
+	}
+
 	public function setParticipant(?string $userId, Participant $participant): void {
 		$this->currentUser = $userId;
 		$this->participant = $participant;
diff --git a/lib/Service/ParticipantService.php b/lib/Service/ParticipantService.php
index be27b16ed..18e2698f1 100644
--- a/lib/Service/ParticipantService.php
+++ b/lib/Service/ParticipantService.php
@@ -326,6 +326,9 @@ class ParticipantService {
 			if (isset($participant['displayName'])) {
 				$attendee->setDisplayName($participant['displayName']);
 			}
+			if (isset($participant['accessToken'])) {
+				$attendee->setAccessToken($participant['accessToken']);
+			}
 			$attendee->setParticipantType($participant['participantType'] ?? Participant::USER);
 			$attendee->setLastReadMessage($lastMessage);
 			$attendee->setReadPrivacy($readPrivacy);