Updated 18 files, added 1692 files and deleted includes/system/compare.inc (automated)

1 files changed, 1081 insertions, 0 deletions

diff --git a/includes/external/matrix/node_modules/matrix-js-sdk/src/models/room-state.ts b/includes/external/matrix/node_modules/matrix-js-sdk/src/models/room-state.ts
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+++ b/includes/external/matrix/node_modules/matrix-js-sdk/src/models/room-state.ts
@@ -0,0 +1,1081 @@
+/*
+Copyright 2015 - 2021 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { RoomMember } from "./room-member";
+import { logger } from "../logger";
+import * as utils from "../utils";
+import { EventType, UNSTABLE_MSC2716_MARKER } from "../@types/event";
+import { IEvent, MatrixEvent, MatrixEventEvent } from "./event";
+import { MatrixClient } from "../client";
+import { GuestAccess, HistoryVisibility, IJoinRuleEventContent, JoinRule } from "../@types/partials";
+import { TypedEventEmitter } from "./typed-event-emitter";
+import { Beacon, BeaconEvent, BeaconEventHandlerMap, getBeaconInfoIdentifier, BeaconIdentifier } from "./beacon";
+import { TypedReEmitter } from "../ReEmitter";
+import { M_BEACON, M_BEACON_INFO } from "../@types/beacon";
+
+export interface IMarkerFoundOptions {
+    /** Whether the timeline was empty before the marker event arrived in the
+     *  room. This could be happen in a variety of cases:
+     *  1. From the initial sync
+     *  2. It's the first state we're seeing after joining the room
+     *  3. Or whether it's coming from `syncFromCache`
+     *
+     * A marker event refers to `UNSTABLE_MSC2716_MARKER` and indicates that
+     * history was imported somewhere back in time. It specifically points to an
+     * MSC2716 insertion event where the history was imported at. Marker events
+     * are sent as state events so they are easily discoverable by clients and
+     * homeservers and don't get lost in timeline gaps.
+     */
+    timelineWasEmpty?: boolean;
+}
+
+// possible statuses for out-of-band member loading
+enum OobStatus {
+    NotStarted,
+    InProgress,
+    Finished,
+}
+
+export interface IPowerLevelsContent {
+    users?: Record<string, number>;
+    events?: Record<string, number>;
+    // eslint-disable-next-line camelcase
+    users_default?: number;
+    // eslint-disable-next-line camelcase
+    events_default?: number;
+    // eslint-disable-next-line camelcase
+    state_default?: number;
+    ban?: number;
+    kick?: number;
+    redact?: number;
+}
+
+export enum RoomStateEvent {
+    Events = "RoomState.events",
+    Members = "RoomState.members",
+    NewMember = "RoomState.newMember",
+    Update = "RoomState.update", // signals batches of updates without specificity
+    BeaconLiveness = "RoomState.BeaconLiveness",
+    Marker = "RoomState.Marker",
+}
+
+export type RoomStateEventHandlerMap = {
+    /**
+     * Fires whenever the event dictionary in room state is updated.
+     * @param event - The matrix event which caused this event to fire.
+     * @param state - The room state whose RoomState.events dictionary
+     * was updated.
+     * @param prevEvent - The event being replaced by the new state, if
+     * known. Note that this can differ from `getPrevContent()` on the new state event
+     * as this is the store's view of the last state, not the previous state provided
+     * by the server.
+     * @example
+     * ```
+     * matrixClient.on("RoomState.events", function(event, state, prevEvent){
+     *   var newStateEvent = event;
+     * });
+     * ```
+     */
+    [RoomStateEvent.Events]: (event: MatrixEvent, state: RoomState, lastStateEvent: MatrixEvent | null) => void;
+    /**
+     * Fires whenever a member in the members dictionary is updated in any way.
+     * @param event - The matrix event which caused this event to fire.
+     * @param state - The room state whose RoomState.members dictionary
+     * was updated.
+     * @param member - The room member that was updated.
+     * @example
+     * ```
+     * matrixClient.on("RoomState.members", function(event, state, member){
+     *   var newMembershipState = member.membership;
+     * });
+     * ```
+     */
+    [RoomStateEvent.Members]: (event: MatrixEvent, state: RoomState, member: RoomMember) => void;
+    /**
+     * Fires whenever a member is added to the members dictionary. The RoomMember
+     * will not be fully populated yet (e.g. no membership state) but will already
+     * be available in the members dictionary.
+     * @param event - The matrix event which caused this event to fire.
+     * @param state - The room state whose RoomState.members dictionary
+     * was updated with a new entry.
+     * @param member - The room member that was added.
+     * @example
+     * ```
+     * matrixClient.on("RoomState.newMember", function(event, state, member){
+     *   // add event listeners on 'member'
+     * });
+     * ```
+     */
+    [RoomStateEvent.NewMember]: (event: MatrixEvent, state: RoomState, member: RoomMember) => void;
+    [RoomStateEvent.Update]: (state: RoomState) => void;
+    [RoomStateEvent.BeaconLiveness]: (state: RoomState, hasLiveBeacons: boolean) => void;
+    [RoomStateEvent.Marker]: (event: MatrixEvent, setStateOptions?: IMarkerFoundOptions) => void;
+    [BeaconEvent.New]: (event: MatrixEvent, beacon: Beacon) => void;
+};
+
+type EmittedEvents = RoomStateEvent | BeaconEvent;
+type EventHandlerMap = RoomStateEventHandlerMap & BeaconEventHandlerMap;
+
+export class RoomState extends TypedEventEmitter<EmittedEvents, EventHandlerMap> {
+    public readonly reEmitter = new TypedReEmitter<EmittedEvents, EventHandlerMap>(this);
+    private sentinels: Record<string, RoomMember> = {}; // userId: RoomMember
+    // stores fuzzy matches to a list of userIDs (applies utils.removeHiddenChars to keys)
+    private displayNameToUserIds = new Map<string, string[]>();
+    private userIdsToDisplayNames: Record<string, string> = {};
+    private tokenToInvite: Record<string, MatrixEvent> = {}; // 3pid invite state_key to m.room.member invite
+    private joinedMemberCount: number | null = null; // cache of the number of joined members
+    // joined members count from summary api
+    // once set, we know the server supports the summary api
+    // and we should only trust that
+    // we could also only trust that before OOB members
+    // are loaded but doesn't seem worth the hassle atm
+    private summaryJoinedMemberCount: number | null = null;
+    // same for invited member count
+    private invitedMemberCount: number | null = null;
+    private summaryInvitedMemberCount: number | null = null;
+    private modified = -1;
+
+    // XXX: Should be read-only
+    // The room member dictionary, keyed on the user's ID.
+    public members: Record<string, RoomMember> = {}; // userId: RoomMember
+    // The state events dictionary, keyed on the event type and then the state_key value.
+    public events = new Map<string, Map<string, MatrixEvent>>(); // Map<eventType, Map<stateKey, MatrixEvent>>
+    // The pagination token for this state.
+    public paginationToken: string | null = null;
+
+    public readonly beacons = new Map<BeaconIdentifier, Beacon>();
+    private _liveBeaconIds: BeaconIdentifier[] = [];
+
+    /**
+     * Construct room state.
+     *
+     * Room State represents the state of the room at a given point.
+     * It can be mutated by adding state events to it.
+     * There are two types of room member associated with a state event:
+     * normal member objects (accessed via getMember/getMembers) which mutate
+     * with the state to represent the current state of that room/user, e.g.
+     * the object returned by `getMember('@bob:example.com')` will mutate to
+     * get a different display name if Bob later changes his display name
+     * in the room.
+     * There are also 'sentinel' members (accessed via getSentinelMember).
+     * These also represent the state of room members at the point in time
+     * represented by the RoomState object, but unlike objects from getMember,
+     * sentinel objects will always represent the room state as at the time
+     * getSentinelMember was called, so if Bob subsequently changes his display
+     * name, a room member object previously acquired with getSentinelMember
+     * will still have his old display name. Calling getSentinelMember again
+     * after the display name change will return a new RoomMember object
+     * with Bob's new display name.
+     *
+     * @param roomId - Optional. The ID of the room which has this state.
+     * If none is specified it just tracks paginationTokens, useful for notifTimelineSet
+     * @param oobMemberFlags - Optional. The state of loading out of bound members.
+     * As the timeline might get reset while they are loading, this state needs to be inherited
+     * and shared when the room state is cloned for the new timeline.
+     * This should only be passed from clone.
+     */
+    public constructor(public readonly roomId: string, private oobMemberFlags = { status: OobStatus.NotStarted }) {
+        super();
+        this.updateModifiedTime();
+    }
+
+    /**
+     * Returns the number of joined members in this room
+     * This method caches the result.
+     * @returns The number of members in this room whose membership is 'join'
+     */
+    public getJoinedMemberCount(): number {
+        if (this.summaryJoinedMemberCount !== null) {
+            return this.summaryJoinedMemberCount;
+        }
+        if (this.joinedMemberCount === null) {
+            this.joinedMemberCount = this.getMembers().reduce((count, m) => {
+                return m.membership === "join" ? count + 1 : count;
+            }, 0);
+        }
+        return this.joinedMemberCount;
+    }
+
+    /**
+     * Set the joined member count explicitly (like from summary part of the sync response)
+     * @param count - the amount of joined members
+     */
+    public setJoinedMemberCount(count: number): void {
+        this.summaryJoinedMemberCount = count;
+    }
+
+    /**
+     * Returns the number of invited members in this room
+     * @returns The number of members in this room whose membership is 'invite'
+     */
+    public getInvitedMemberCount(): number {
+        if (this.summaryInvitedMemberCount !== null) {
+            return this.summaryInvitedMemberCount;
+        }
+        if (this.invitedMemberCount === null) {
+            this.invitedMemberCount = this.getMembers().reduce((count, m) => {
+                return m.membership === "invite" ? count + 1 : count;
+            }, 0);
+        }
+        return this.invitedMemberCount;
+    }
+
+    /**
+     * Set the amount of invited members in this room
+     * @param count - the amount of invited members
+     */
+    public setInvitedMemberCount(count: number): void {
+        this.summaryInvitedMemberCount = count;
+    }
+
+    /**
+     * Get all RoomMembers in this room.
+     * @returns A list of RoomMembers.
+     */
+    public getMembers(): RoomMember[] {
+        return Object.values(this.members);
+    }
+
+    /**
+     * Get all RoomMembers in this room, excluding the user IDs provided.
+     * @param excludedIds - The user IDs to exclude.
+     * @returns A list of RoomMembers.
+     */
+    public getMembersExcept(excludedIds: string[]): RoomMember[] {
+        return this.getMembers().filter((m) => !excludedIds.includes(m.userId));
+    }
+
+    /**
+     * Get a room member by their user ID.
+     * @param userId - The room member's user ID.
+     * @returns The member or null if they do not exist.
+     */
+    public getMember(userId: string): RoomMember | null {
+        return this.members[userId] || null;
+    }
+
+    /**
+     * Get a room member whose properties will not change with this room state. You
+     * typically want this if you want to attach a RoomMember to a MatrixEvent which
+     * may no longer be represented correctly by Room.currentState or Room.oldState.
+     * The term 'sentinel' refers to the fact that this RoomMember is an unchanging
+     * guardian for state at this particular point in time.
+     * @param userId - The room member's user ID.
+     * @returns The member or null if they do not exist.
+     */
+    public getSentinelMember(userId: string): RoomMember | null {
+        if (!userId) return null;
+        let sentinel = this.sentinels[userId];
+
+        if (sentinel === undefined) {
+            sentinel = new RoomMember(this.roomId, userId);
+            const member = this.members[userId];
+            if (member?.events.member) {
+                sentinel.setMembershipEvent(member.events.member, this);
+            }
+            this.sentinels[userId] = sentinel;
+        }
+        return sentinel;
+    }
+
+    /**
+     * Get state events from the state of the room.
+     * @param eventType - The event type of the state event.
+     * @param stateKey - Optional. The state_key of the state event. If
+     * this is `undefined` then all matching state events will be
+     * returned.
+     * @returns A list of events if state_key was
+     * `undefined`, else a single event (or null if no match found).
+     */
+    public getStateEvents(eventType: EventType | string): MatrixEvent[];
+    public getStateEvents(eventType: EventType | string, stateKey: string): MatrixEvent | null;
+    public getStateEvents(eventType: EventType | string, stateKey?: string): MatrixEvent[] | MatrixEvent | null {
+        if (!this.events.has(eventType)) {
+            // no match
+            return stateKey === undefined ? [] : null;
+        }
+        if (stateKey === undefined) {
+            // return all values
+            return Array.from(this.events.get(eventType)!.values());
+        }
+        const event = this.events.get(eventType)!.get(stateKey);
+        return event ? event : null;
+    }
+
+    public get hasLiveBeacons(): boolean {
+        return !!this.liveBeaconIds?.length;
+    }
+
+    public get liveBeaconIds(): BeaconIdentifier[] {
+        return this._liveBeaconIds;
+    }
+
+    /**
+     * Creates a copy of this room state so that mutations to either won't affect the other.
+     * @returns the copy of the room state
+     */
+    public clone(): RoomState {
+        const copy = new RoomState(this.roomId, this.oobMemberFlags);
+
+        // Ugly hack: because setStateEvents will mark
+        // members as susperseding future out of bound members
+        // if loading is in progress (through oobMemberFlags)
+        // since these are not new members, we're merely copying them
+        // set the status to not started
+        // after copying, we set back the status
+        const status = this.oobMemberFlags.status;
+        this.oobMemberFlags.status = OobStatus.NotStarted;
+
+        Array.from(this.events.values()).forEach((eventsByStateKey) => {
+            copy.setStateEvents(Array.from(eventsByStateKey.values()));
+        });
+
+        // Ugly hack: see above
+        this.oobMemberFlags.status = status;
+
+        if (this.summaryInvitedMemberCount !== null) {
+            copy.setInvitedMemberCount(this.getInvitedMemberCount());
+        }
+        if (this.summaryJoinedMemberCount !== null) {
+            copy.setJoinedMemberCount(this.getJoinedMemberCount());
+        }
+
+        // copy out of band flags if needed
+        if (this.oobMemberFlags.status == OobStatus.Finished) {
+            // copy markOutOfBand flags
+            this.getMembers().forEach((member) => {
+                if (member.isOutOfBand()) {
+                    copy.getMember(member.userId)?.markOutOfBand();
+                }
+            });
+        }
+
+        return copy;
+    }
+
+    /**
+     * Add previously unknown state events.
+     * When lazy loading members while back-paginating,
+     * the relevant room state for the timeline chunk at the end
+     * of the chunk can be set with this method.
+     * @param events - state events to prepend
+     */
+    public setUnknownStateEvents(events: MatrixEvent[]): void {
+        const unknownStateEvents = events.filter((event) => {
+            return !this.events.has(event.getType()) || !this.events.get(event.getType())!.has(event.getStateKey()!);
+        });
+
+        this.setStateEvents(unknownStateEvents);
+    }
+
+    /**
+     * Add an array of one or more state MatrixEvents, overwriting any existing
+     * state with the same `{type, stateKey}` tuple. Will fire "RoomState.events"
+     * for every event added. May fire "RoomState.members" if there are
+     * `m.room.member` events. May fire "RoomStateEvent.Marker" if there are
+     * `UNSTABLE_MSC2716_MARKER` events.
+     * @param stateEvents - a list of state events for this room.
+     *
+     * @remarks
+     * Fires {@link RoomStateEvent.Members}
+     * Fires {@link RoomStateEvent.NewMember}
+     * Fires {@link RoomStateEvent.Events}
+     * Fires {@link RoomStateEvent.Marker}
+     */
+    public setStateEvents(stateEvents: MatrixEvent[], markerFoundOptions?: IMarkerFoundOptions): void {
+        this.updateModifiedTime();
+
+        // update the core event dict
+        stateEvents.forEach((event) => {
+            if (event.getRoomId() !== this.roomId || !event.isState()) return;
+
+            if (M_BEACON_INFO.matches(event.getType())) {
+                this.setBeacon(event);
+            }
+
+            const lastStateEvent = this.getStateEventMatching(event);
+            this.setStateEvent(event);
+            if (event.getType() === EventType.RoomMember) {
+                this.updateDisplayNameCache(event.getStateKey()!, event.getContent().displayname ?? "");
+                this.updateThirdPartyTokenCache(event);
+            }
+            this.emit(RoomStateEvent.Events, event, this, lastStateEvent);
+        });
+
+        this.onBeaconLivenessChange();
+        // update higher level data structures. This needs to be done AFTER the
+        // core event dict as these structures may depend on other state events in
+        // the given array (e.g. disambiguating display names in one go to do both
+        // clashing names rather than progressively which only catches 1 of them).
+        stateEvents.forEach((event) => {
+            if (event.getRoomId() !== this.roomId || !event.isState()) return;
+
+            if (event.getType() === EventType.RoomMember) {
+                const userId = event.getStateKey()!;
+
+                // leave events apparently elide the displayname or avatar_url,
+                // so let's fake one up so that we don't leak user ids
+                // into the timeline
+                if (event.getContent().membership === "leave" || event.getContent().membership === "ban") {
+                    event.getContent().avatar_url = event.getContent().avatar_url || event.getPrevContent().avatar_url;
+                    event.getContent().displayname =
+                        event.getContent().displayname || event.getPrevContent().displayname;
+                }
+
+                const member = this.getOrCreateMember(userId, event);
+                member.setMembershipEvent(event, this);
+                this.updateMember(member);
+                this.emit(RoomStateEvent.Members, event, this, member);
+            } else if (event.getType() === EventType.RoomPowerLevels) {
+                // events with unknown state keys should be ignored
+                // and should not aggregate onto members power levels
+                if (event.getStateKey() !== "") {
+                    return;
+                }
+                const members = Object.values(this.members);
+                members.forEach((member) => {
+                    // We only propagate `RoomState.members` event if the
+                    // power levels has been changed
+                    // large room suffer from large re-rendering especially when not needed
+                    const oldLastModified = member.getLastModifiedTime();
+                    member.setPowerLevelEvent(event);
+                    if (oldLastModified !== member.getLastModifiedTime()) {
+                        this.emit(RoomStateEvent.Members, event, this, member);
+                    }
+                });
+
+                // assume all our sentinels are now out-of-date
+                this.sentinels = {};
+            } else if (UNSTABLE_MSC2716_MARKER.matches(event.getType())) {
+                this.emit(RoomStateEvent.Marker, event, markerFoundOptions);
+            }
+        });
+
+        this.emit(RoomStateEvent.Update, this);
+    }
+
+    public async processBeaconEvents(events: MatrixEvent[], matrixClient: MatrixClient): Promise<void> {
+        if (
+            !events.length ||
+            // discard locations if we have no beacons
+            !this.beacons.size
+        ) {
+            return;
+        }
+
+        const beaconByEventIdDict = [...this.beacons.values()].reduce<Record<string, Beacon>>((dict, beacon) => {
+            dict[beacon.beaconInfoId] = beacon;
+            return dict;
+        }, {});
+
+        const processBeaconRelation = (beaconInfoEventId: string, event: MatrixEvent): void => {
+            if (!M_BEACON.matches(event.getType())) {
+                return;
+            }
+
+            const beacon = beaconByEventIdDict[beaconInfoEventId];
+
+            if (beacon) {
+                beacon.addLocations([event]);
+            }
+        };
+
+        for (const event of events) {
+            const relatedToEventId = event.getRelation()?.event_id;
+            // not related to a beacon we know about; discard
+            if (!relatedToEventId || !beaconByEventIdDict[relatedToEventId]) return;
+            if (!M_BEACON.matches(event.getType()) && !event.isEncrypted()) return;
+
+            try {
+                await matrixClient.decryptEventIfNeeded(event);
+                processBeaconRelation(relatedToEventId, event);
+            } catch {
+                if (event.isDecryptionFailure()) {
+                    // add an event listener for once the event is decrypted.
+                    event.once(MatrixEventEvent.Decrypted, async () => {
+                        processBeaconRelation(relatedToEventId, event);
+                    });
+                }
+            }
+        }
+    }
+
+    /**
+     * Looks up a member by the given userId, and if it doesn't exist,
+     * create it and emit the `RoomState.newMember` event.
+     * This method makes sure the member is added to the members dictionary
+     * before emitting, as this is done from setStateEvents and setOutOfBandMember.
+     * @param userId - the id of the user to look up
+     * @param event - the membership event for the (new) member. Used to emit.
+     * @returns the member, existing or newly created.
+     *
+     * @remarks
+     * Fires {@link RoomStateEvent.NewMember}
+     */
+    private getOrCreateMember(userId: string, event: MatrixEvent): RoomMember {
+        let member = this.members[userId];
+        if (!member) {
+            member = new RoomMember(this.roomId, userId);
+            // add member to members before emitting any events,
+            // as event handlers often lookup the member
+            this.members[userId] = member;
+            this.emit(RoomStateEvent.NewMember, event, this, member);
+        }
+        return member;
+    }
+
+    private setStateEvent(event: MatrixEvent): void {
+        if (!this.events.has(event.getType())) {
+            this.events.set(event.getType(), new Map());
+        }
+        this.events.get(event.getType())!.set(event.getStateKey()!, event);
+    }
+
+    /**
+     * @experimental
+     */
+    private setBeacon(event: MatrixEvent): void {
+        const beaconIdentifier = getBeaconInfoIdentifier(event);
+
+        if (this.beacons.has(beaconIdentifier)) {
+            const beacon = this.beacons.get(beaconIdentifier)!;
+
+            if (event.isRedacted()) {
+                if (beacon.beaconInfoId === (<IEvent>event.getRedactionEvent())?.redacts) {
+                    beacon.destroy();
+                    this.beacons.delete(beaconIdentifier);
+                }
+                return;
+            }
+
+            return beacon.update(event);
+        }
+
+        if (event.isRedacted()) {
+            return;
+        }
+
+        const beacon = new Beacon(event);
+
+        this.reEmitter.reEmit<BeaconEvent, BeaconEvent>(beacon, [
+            BeaconEvent.New,
+            BeaconEvent.Update,
+            BeaconEvent.Destroy,
+            BeaconEvent.LivenessChange,
+        ]);
+
+        this.emit(BeaconEvent.New, event, beacon);
+        beacon.on(BeaconEvent.LivenessChange, this.onBeaconLivenessChange.bind(this));
+        beacon.on(BeaconEvent.Destroy, this.onBeaconLivenessChange.bind(this));
+
+        this.beacons.set(beacon.identifier, beacon);
+    }
+
+    /**
+     * @experimental
+     * Check liveness of room beacons
+     * emit RoomStateEvent.BeaconLiveness event
+     */
+    private onBeaconLivenessChange(): void {
+        this._liveBeaconIds = Array.from(this.beacons.values())
+            .filter((beacon) => beacon.isLive)
+            .map((beacon) => beacon.identifier);
+
+        this.emit(RoomStateEvent.BeaconLiveness, this, this.hasLiveBeacons);
+    }
+
+    private getStateEventMatching(event: MatrixEvent): MatrixEvent | null {
+        return this.events.get(event.getType())?.get(event.getStateKey()!) ?? null;
+    }
+
+    private updateMember(member: RoomMember): void {
+        // this member may have a power level already, so set it.
+        const pwrLvlEvent = this.getStateEvents(EventType.RoomPowerLevels, "");
+        if (pwrLvlEvent) {
+            member.setPowerLevelEvent(pwrLvlEvent);
+        }
+
+        // blow away the sentinel which is now outdated
+        delete this.sentinels[member.userId];
+
+        this.members[member.userId] = member;
+        this.joinedMemberCount = null;
+        this.invitedMemberCount = null;
+    }
+
+    /**
+     * Get the out-of-band members loading state, whether loading is needed or not.
+     * Note that loading might be in progress and hence isn't needed.
+     * @returns whether or not the members of this room need to be loaded
+     */
+    public needsOutOfBandMembers(): boolean {
+        return this.oobMemberFlags.status === OobStatus.NotStarted;
+    }
+
+    /**
+     * Check if loading of out-of-band-members has completed
+     *
+     * @returns true if the full membership list of this room has been loaded. False if it is not started or is in
+     *    progress.
+     */
+    public outOfBandMembersReady(): boolean {
+        return this.oobMemberFlags.status === OobStatus.Finished;
+    }
+
+    /**
+     * Mark this room state as waiting for out-of-band members,
+     * ensuring it doesn't ask for them to be requested again
+     * through needsOutOfBandMembers
+     */
+    public markOutOfBandMembersStarted(): void {
+        if (this.oobMemberFlags.status !== OobStatus.NotStarted) {
+            return;
+        }
+        this.oobMemberFlags.status = OobStatus.InProgress;
+    }
+
+    /**
+     * Mark this room state as having failed to fetch out-of-band members
+     */
+    public markOutOfBandMembersFailed(): void {
+        if (this.oobMemberFlags.status !== OobStatus.InProgress) {
+            return;
+        }
+        this.oobMemberFlags.status = OobStatus.NotStarted;
+    }
+
+    /**
+     * Clears the loaded out-of-band members
+     */
+    public clearOutOfBandMembers(): void {
+        let count = 0;
+        Object.keys(this.members).forEach((userId) => {
+            const member = this.members[userId];
+            if (member.isOutOfBand()) {
+                ++count;
+                delete this.members[userId];
+            }
+        });
+        logger.log(`LL: RoomState removed ${count} members...`);
+        this.oobMemberFlags.status = OobStatus.NotStarted;
+    }
+
+    /**
+     * Sets the loaded out-of-band members.
+     * @param stateEvents - array of membership state events
+     */
+    public setOutOfBandMembers(stateEvents: MatrixEvent[]): void {
+        logger.log(`LL: RoomState about to set ${stateEvents.length} OOB members ...`);
+        if (this.oobMemberFlags.status !== OobStatus.InProgress) {
+            return;
+        }
+        logger.log(`LL: RoomState put in finished state ...`);
+        this.oobMemberFlags.status = OobStatus.Finished;
+        stateEvents.forEach((e) => this.setOutOfBandMember(e));
+        this.emit(RoomStateEvent.Update, this);
+    }
+
+    /**
+     * Sets a single out of band member, used by both setOutOfBandMembers and clone
+     * @param stateEvent - membership state event
+     */
+    private setOutOfBandMember(stateEvent: MatrixEvent): void {
+        if (stateEvent.getType() !== EventType.RoomMember) {
+            return;
+        }
+        const userId = stateEvent.getStateKey()!;
+        const existingMember = this.getMember(userId);
+        // never replace members received as part of the sync
+        if (existingMember && !existingMember.isOutOfBand()) {
+            return;
+        }
+
+        const member = this.getOrCreateMember(userId, stateEvent);
+        member.setMembershipEvent(stateEvent, this);
+        // needed to know which members need to be stored seperately
+        // as they are not part of the sync accumulator
+        // this is cleared by setMembershipEvent so when it's updated through /sync
+        member.markOutOfBand();
+
+        this.updateDisplayNameCache(member.userId, member.name);
+
+        this.setStateEvent(stateEvent);
+        this.updateMember(member);
+        this.emit(RoomStateEvent.Members, stateEvent, this, member);
+    }
+
+    /**
+     * Set the current typing event for this room.
+     * @param event - The typing event
+     */
+    public setTypingEvent(event: MatrixEvent): void {
+        Object.values(this.members).forEach(function (member) {
+            member.setTypingEvent(event);
+        });
+    }
+
+    /**
+     * Get the m.room.member event which has the given third party invite token.
+     *
+     * @param token - The token
+     * @returns The m.room.member event or null
+     */
+    public getInviteForThreePidToken(token: string): MatrixEvent | null {
+        return this.tokenToInvite[token] || null;
+    }
+
+    /**
+     * Update the last modified time to the current time.
+     */
+    private updateModifiedTime(): void {
+        this.modified = Date.now();
+    }
+
+    /**
+     * Get the timestamp when this room state was last updated. This timestamp is
+     * updated when this object has received new state events.
+     * @returns The timestamp
+     */
+    public getLastModifiedTime(): number {
+        return this.modified;
+    }
+
+    /**
+     * Get user IDs with the specified or similar display names.
+     * @param displayName - The display name to get user IDs from.
+     * @returns An array of user IDs or an empty array.
+     */
+    public getUserIdsWithDisplayName(displayName: string): string[] {
+        return this.displayNameToUserIds.get(utils.removeHiddenChars(displayName)) ?? [];
+    }
+
+    /**
+     * Returns true if userId is in room, event is not redacted and either sender of
+     * mxEvent or has power level sufficient to redact events other than their own.
+     * @param mxEvent - The event to test permission for
+     * @param userId - The user ID of the user to test permission for
+     * @returns true if the given used ID can redact given event
+     */
+    public maySendRedactionForEvent(mxEvent: MatrixEvent, userId: string): boolean {
+        const member = this.getMember(userId);
+        if (!member || member.membership === "leave") return false;
+
+        if (mxEvent.status || mxEvent.isRedacted()) return false;
+
+        // The user may have been the sender, but they can't redact their own message
+        // if redactions are blocked.
+        const canRedact = this.maySendEvent(EventType.RoomRedaction, userId);
+        if (mxEvent.getSender() === userId) return canRedact;
+
+        return this.hasSufficientPowerLevelFor("redact", member.powerLevel);
+    }
+
+    /**
+     * Returns true if the given power level is sufficient for action
+     * @param action - The type of power level to check
+     * @param powerLevel - The power level of the member
+     * @returns true if the given power level is sufficient
+     */
+    public hasSufficientPowerLevelFor(action: "ban" | "kick" | "redact", powerLevel: number): boolean {
+        const powerLevelsEvent = this.getStateEvents(EventType.RoomPowerLevels, "");
+
+        let powerLevels: IPowerLevelsContent = {};
+        if (powerLevelsEvent) {
+            powerLevels = powerLevelsEvent.getContent();
+        }
+
+        let requiredLevel = 50;
+        if (utils.isNumber(powerLevels[action])) {
+            requiredLevel = powerLevels[action]!;
+        }
+
+        return powerLevel >= requiredLevel;
+    }
+
+    /**
+     * Short-form for maySendEvent('m.room.message', userId)
+     * @param userId - The user ID of the user to test permission for
+     * @returns true if the given user ID should be permitted to send
+     *                   message events into the given room.
+     */
+    public maySendMessage(userId: string): boolean {
+        return this.maySendEventOfType(EventType.RoomMessage, userId, false);
+    }
+
+    /**
+     * Returns true if the given user ID has permission to send a normal
+     * event of type `eventType` into this room.
+     * @param eventType - The type of event to test
+     * @param userId - The user ID of the user to test permission for
+     * @returns true if the given user ID should be permitted to send
+     *                        the given type of event into this room,
+     *                        according to the room's state.
+     */
+    public maySendEvent(eventType: EventType | string, userId: string): boolean {
+        return this.maySendEventOfType(eventType, userId, false);
+    }
+
+    /**
+     * Returns true if the given MatrixClient has permission to send a state
+     * event of type `stateEventType` into this room.
+     * @param stateEventType - The type of state events to test
+     * @param cli - The client to test permission for
+     * @returns true if the given client should be permitted to send
+     *                        the given type of state event into this room,
+     *                        according to the room's state.
+     */
+    public mayClientSendStateEvent(stateEventType: EventType | string, cli: MatrixClient): boolean {
+        if (cli.isGuest() || !cli.credentials.userId) {
+            return false;
+        }
+        return this.maySendStateEvent(stateEventType, cli.credentials.userId);
+    }
+
+    /**
+     * Returns true if the given user ID has permission to send a state
+     * event of type `stateEventType` into this room.
+     * @param stateEventType - The type of state events to test
+     * @param userId - The user ID of the user to test permission for
+     * @returns true if the given user ID should be permitted to send
+     *                        the given type of state event into this room,
+     *                        according to the room's state.
+     */
+    public maySendStateEvent(stateEventType: EventType | string, userId: string): boolean {
+        return this.maySendEventOfType(stateEventType, userId, true);
+    }
+
+    /**
+     * Returns true if the given user ID has permission to send a normal or state
+     * event of type `eventType` into this room.
+     * @param eventType - The type of event to test
+     * @param userId - The user ID of the user to test permission for
+     * @param state - If true, tests if the user may send a state
+     event of this type. Otherwise tests whether
+     they may send a regular event.
+     * @returns true if the given user ID should be permitted to send
+     *                        the given type of event into this room,
+     *                        according to the room's state.
+     */
+    private maySendEventOfType(eventType: EventType | string, userId: string, state: boolean): boolean {
+        const powerLevelsEvent = this.getStateEvents(EventType.RoomPowerLevels, "");
+
+        let powerLevels: IPowerLevelsContent;
+        let eventsLevels: Record<EventType | string, number> = {};
+
+        let stateDefault = 0;
+        let eventsDefault = 0;
+        let powerLevel = 0;
+        if (powerLevelsEvent) {
+            powerLevels = powerLevelsEvent.getContent();
+            eventsLevels = powerLevels.events || {};
+
+            if (Number.isSafeInteger(powerLevels.state_default)) {
+                stateDefault = powerLevels.state_default!;
+            } else {
+                stateDefault = 50;
+            }
+
+            const userPowerLevel = powerLevels.users && powerLevels.users[userId];
+            if (Number.isSafeInteger(userPowerLevel)) {
+                powerLevel = userPowerLevel!;
+            } else if (Number.isSafeInteger(powerLevels.users_default)) {
+                powerLevel = powerLevels.users_default!;
+            }
+
+            if (Number.isSafeInteger(powerLevels.events_default)) {
+                eventsDefault = powerLevels.events_default!;
+            }
+        }
+
+        let requiredLevel = state ? stateDefault : eventsDefault;
+        if (Number.isSafeInteger(eventsLevels[eventType])) {
+            requiredLevel = eventsLevels[eventType];
+        }
+        return powerLevel >= requiredLevel;
+    }
+
+    /**
+     * Returns true if the given user ID has permission to trigger notification
+     * of type `notifLevelKey`
+     * @param notifLevelKey - The level of notification to test (eg. 'room')
+     * @param userId - The user ID of the user to test permission for
+     * @returns true if the given user ID has permission to trigger a
+     *                        notification of this type.
+     */
+    public mayTriggerNotifOfType(notifLevelKey: string, userId: string): boolean {
+        const member = this.getMember(userId);
+        if (!member) {
+            return false;
+        }
+
+        const powerLevelsEvent = this.getStateEvents(EventType.RoomPowerLevels, "");
+
+        let notifLevel = 50;
+        if (
+            powerLevelsEvent &&
+            powerLevelsEvent.getContent() &&
+            powerLevelsEvent.getContent().notifications &&
+            utils.isNumber(powerLevelsEvent.getContent().notifications[notifLevelKey])
+        ) {
+            notifLevel = powerLevelsEvent.getContent().notifications[notifLevelKey];
+        }
+
+        return member.powerLevel >= notifLevel;
+    }
+
+    /**
+     * Returns the join rule based on the m.room.join_rule state event, defaulting to `invite`.
+     * @returns the join_rule applied to this room
+     */
+    public getJoinRule(): JoinRule {
+        const joinRuleEvent = this.getStateEvents(EventType.RoomJoinRules, "");
+        const joinRuleContent: Partial<IJoinRuleEventContent> = joinRuleEvent?.getContent() ?? {};
+        return joinRuleContent["join_rule"] || JoinRule.Invite;
+    }
+
+    /**
+     * Returns the history visibility based on the m.room.history_visibility state event, defaulting to `shared`.
+     * @returns the history_visibility applied to this room
+     */
+    public getHistoryVisibility(): HistoryVisibility {
+        const historyVisibilityEvent = this.getStateEvents(EventType.RoomHistoryVisibility, "");
+        const historyVisibilityContent = historyVisibilityEvent?.getContent() ?? {};
+        return historyVisibilityContent["history_visibility"] || HistoryVisibility.Shared;
+    }
+
+    /**
+     * Returns the guest access based on the m.room.guest_access state event, defaulting to `shared`.
+     * @returns the guest_access applied to this room
+     */
+    public getGuestAccess(): GuestAccess {
+        const guestAccessEvent = this.getStateEvents(EventType.RoomGuestAccess, "");
+        const guestAccessContent = guestAccessEvent?.getContent() ?? {};
+        return guestAccessContent["guest_access"] || GuestAccess.Forbidden;
+    }
+
+    /**
+     * Find the predecessor room based on this room state.
+     *
+     * @param msc3946ProcessDynamicPredecessor - if true, look for an
+     * m.room.predecessor state event and use it if found (MSC3946).
+     * @returns null if this room has no predecessor. Otherwise, returns
+     * the roomId, last eventId and viaServers of the predecessor room.
+     *
+     * If msc3946ProcessDynamicPredecessor is true, use m.predecessor events
+     * as well as m.room.create events to find predecessors.
+     *
+     * Note: if an m.predecessor event is used, eventId may be undefined
+     * since last_known_event_id is optional.
+     *
+     * Note: viaServers may be undefined, and will definitely be undefined if
+     * this predecessor comes from a RoomCreate event (rather than a
+     * RoomPredecessor, which has the optional via_servers property).
+     */
+    public findPredecessor(
+        msc3946ProcessDynamicPredecessor = false,
+    ): { roomId: string; eventId?: string; viaServers?: string[] } | null {
+        // Note: the tests for this function are against Room.findPredecessor,
+        // which just calls through to here.
+
+        if (msc3946ProcessDynamicPredecessor) {
+            const predecessorEvent = this.getStateEvents(EventType.RoomPredecessor, "");
+            if (predecessorEvent) {
+                const content = predecessorEvent.getContent<{
+                    predecessor_room_id: string;
+                    last_known_event_id?: string;
+                    via_servers?: string[];
+                }>();
+                const roomId = content.predecessor_room_id;
+                let eventId = content.last_known_event_id;
+                if (typeof eventId !== "string") {
+                    eventId = undefined;
+                }
+                let viaServers = content.via_servers;
+                if (!Array.isArray(viaServers)) {
+                    viaServers = undefined;
+                }
+                if (typeof roomId === "string") {
+                    return { roomId, eventId, viaServers };
+                }
+            }
+        }
+
+        const createEvent = this.getStateEvents(EventType.RoomCreate, "");
+        if (createEvent) {
+            const predecessor = createEvent.getContent<{
+                predecessor?: Partial<{
+                    room_id: string;
+                    event_id: string;
+                }>;
+            }>()["predecessor"];
+            if (predecessor) {
+                const roomId = predecessor["room_id"];
+                if (typeof roomId === "string") {
+                    let eventId = predecessor["event_id"];
+                    if (typeof eventId !== "string" || eventId === "") {
+                        eventId = undefined;
+                    }
+                    return { roomId, eventId };
+                }
+            }
+        }
+        return null;
+    }
+
+    private updateThirdPartyTokenCache(memberEvent: MatrixEvent): void {
+        if (!memberEvent.getContent().third_party_invite) {
+            return;
+        }
+        const token = (memberEvent.getContent().third_party_invite.signed || {}).token;
+        if (!token) {
+            return;
+        }
+        const threePidInvite = this.getStateEvents(EventType.RoomThirdPartyInvite, token);
+        if (!threePidInvite) {
+            return;
+        }
+        this.tokenToInvite[token] = memberEvent;
+    }
+
+    private updateDisplayNameCache(userId: string, displayName: string): void {
+        const oldName = this.userIdsToDisplayNames[userId];
+        delete this.userIdsToDisplayNames[userId];
+        if (oldName) {
+            // Remove the old name from the cache.
+            // We clobber the user_id > name lookup but the name -> [user_id] lookup
+            // means we need to remove that user ID from that array rather than nuking
+            // the lot.
+            const strippedOldName = utils.removeHiddenChars(oldName);
+
+            const existingUserIds = this.displayNameToUserIds.get(strippedOldName);
+            if (existingUserIds) {
+                // remove this user ID from this array
+                const filteredUserIDs = existingUserIds.filter((id) => id !== userId);
+                this.displayNameToUserIds.set(strippedOldName, filteredUserIDs);
+            }
+        }
+
+        this.userIdsToDisplayNames[userId] = displayName;
+
+        const strippedDisplayname = displayName && utils.removeHiddenChars(displayName);
+        // an empty stripped displayname (undefined/'') will be set to MXID in room-member.js
+        if (strippedDisplayname) {
+            const arr = this.displayNameToUserIds.get(strippedDisplayname) ?? [];
+            arr.push(userId);
+            this.displayNameToUserIds.set(strippedDisplayname, arr);
+        }
+    }
+}