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diff --git a/includes/external/matrix/node_modules/matrix-js-sdk/src/models/relations.ts b/includes/external/matrix/node_modules/matrix-js-sdk/src/models/relations.ts
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+/*
+Copyright 2019, 2021, 2023 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 { EventStatus, IAggregatedRelation, MatrixEvent, MatrixEventEvent } from "./event";
+import { logger } from "../logger";
+import { RelationType } from "../@types/event";
+import { TypedEventEmitter } from "./typed-event-emitter";
+import { MatrixClient } from "../client";
+import { Room } from "./room";
+
+export enum RelationsEvent {
+    Add = "Relations.add",
+    Remove = "Relations.remove",
+    Redaction = "Relations.redaction",
+}
+
+export type EventHandlerMap = {
+    [RelationsEvent.Add]: (event: MatrixEvent) => void;
+    [RelationsEvent.Remove]: (event: MatrixEvent) => void;
+    [RelationsEvent.Redaction]: (event: MatrixEvent) => void;
+};
+
+const matchesEventType = (eventType: string, targetEventType: string, altTargetEventTypes: string[] = []): boolean =>
+    [targetEventType, ...altTargetEventTypes].includes(eventType);
+
+/**
+ * A container for relation events that supports easy access to common ways of
+ * aggregating such events. Each instance holds events that of a single relation
+ * type and event type. All of the events also relate to the same original event.
+ *
+ * The typical way to get one of these containers is via
+ * EventTimelineSet#getRelationsForEvent.
+ */
+export class Relations extends TypedEventEmitter<RelationsEvent, EventHandlerMap> {
+    private relationEventIds = new Set<string>();
+    private relations = new Set<MatrixEvent>();
+    private annotationsByKey: Record<string, Set<MatrixEvent>> = {};
+    private annotationsBySender: Record<string, Set<MatrixEvent>> = {};
+    private sortedAnnotationsByKey: [string, Set<MatrixEvent>][] = [];
+    private targetEvent: MatrixEvent | null = null;
+    private creationEmitted = false;
+    private readonly client: MatrixClient;
+
+    /**
+     * @param relationType - The type of relation involved, such as "m.annotation", "m.reference", "m.replace", etc.
+     * @param eventType - The relation event's type, such as "m.reaction", etc.
+     * @param client - The client which created this instance. For backwards compatibility also accepts a Room.
+     * @param altEventTypes - alt event types for relation events, for example to support unstable prefixed event types
+     */
+    public constructor(
+        public readonly relationType: RelationType | string,
+        public readonly eventType: string,
+        client: MatrixClient | Room,
+        public readonly altEventTypes?: string[],
+    ) {
+        super();
+        this.client = client instanceof Room ? client.client : client;
+    }
+
+    /**
+     * Add relation events to this collection.
+     *
+     * @param event - The new relation event to be added.
+     */
+    public async addEvent(event: MatrixEvent): Promise<void> {
+        if (this.relationEventIds.has(event.getId()!)) {
+            return;
+        }
+
+        const relation = event.getRelation();
+        if (!relation) {
+            logger.error("Event must have relation info");
+            return;
+        }
+
+        const relationType = relation.rel_type;
+        const eventType = event.getType();
+
+        if (this.relationType !== relationType || !matchesEventType(eventType, this.eventType, this.altEventTypes)) {
+            logger.error("Event relation info doesn't match this container");
+            return;
+        }
+
+        // If the event is in the process of being sent, listen for cancellation
+        // so we can remove the event from the collection.
+        if (event.isSending()) {
+            event.on(MatrixEventEvent.Status, this.onEventStatus);
+        }
+
+        this.relations.add(event);
+        this.relationEventIds.add(event.getId()!);
+
+        if (this.relationType === RelationType.Annotation) {
+            this.addAnnotationToAggregation(event);
+        } else if (this.relationType === RelationType.Replace && this.targetEvent && !this.targetEvent.isState()) {
+            const lastReplacement = await this.getLastReplacement();
+            this.targetEvent.makeReplaced(lastReplacement!);
+        }
+
+        event.on(MatrixEventEvent.BeforeRedaction, this.onBeforeRedaction);
+
+        this.emit(RelationsEvent.Add, event);
+
+        this.maybeEmitCreated();
+    }
+
+    /**
+     * Remove relation event from this collection.
+     *
+     * @param event - The relation event to remove.
+     */
+    public async removeEvent(event: MatrixEvent): Promise<void> {
+        if (!this.relations.has(event)) {
+            return;
+        }
+
+        this.relations.delete(event);
+
+        if (this.relationType === RelationType.Annotation) {
+            this.removeAnnotationFromAggregation(event);
+        } else if (this.relationType === RelationType.Replace && this.targetEvent && !this.targetEvent.isState()) {
+            const lastReplacement = await this.getLastReplacement();
+            this.targetEvent.makeReplaced(lastReplacement!);
+        }
+
+        this.emit(RelationsEvent.Remove, event);
+    }
+
+    /**
+     * Listens for event status changes to remove cancelled events.
+     *
+     * @param event - The event whose status has changed
+     * @param status - The new status
+     */
+    private onEventStatus = (event: MatrixEvent, status: EventStatus | null): void => {
+        if (!event.isSending()) {
+            // Sending is done, so we don't need to listen anymore
+            event.removeListener(MatrixEventEvent.Status, this.onEventStatus);
+            return;
+        }
+        if (status !== EventStatus.CANCELLED) {
+            return;
+        }
+        // Event was cancelled, remove from the collection
+        event.removeListener(MatrixEventEvent.Status, this.onEventStatus);
+        this.removeEvent(event);
+    };
+
+    /**
+     * Get all relation events in this collection.
+     *
+     * These are currently in the order of insertion to this collection, which
+     * won't match timeline order in the case of scrollback.
+     * TODO: Tweak `addEvent` to insert correctly for scrollback.
+     *
+     * Relation events in insertion order.
+     */
+    public getRelations(): MatrixEvent[] {
+        return [...this.relations];
+    }
+
+    private addAnnotationToAggregation(event: MatrixEvent): void {
+        const { key } = event.getRelation() ?? {};
+        if (!key) return;
+
+        let eventsForKey = this.annotationsByKey[key];
+        if (!eventsForKey) {
+            eventsForKey = this.annotationsByKey[key] = new Set();
+            this.sortedAnnotationsByKey.push([key, eventsForKey]);
+        }
+        // Add the new event to the set for this key
+        eventsForKey.add(event);
+        // Re-sort the [key, events] pairs in descending order of event count
+        this.sortedAnnotationsByKey.sort((a, b) => {
+            const aEvents = a[1];
+            const bEvents = b[1];
+            return bEvents.size - aEvents.size;
+        });
+
+        const sender = event.getSender()!;
+        let eventsFromSender = this.annotationsBySender[sender];
+        if (!eventsFromSender) {
+            eventsFromSender = this.annotationsBySender[sender] = new Set();
+        }
+        // Add the new event to the set for this sender
+        eventsFromSender.add(event);
+    }
+
+    private removeAnnotationFromAggregation(event: MatrixEvent): void {
+        const { key } = event.getRelation() ?? {};
+        if (!key) return;
+
+        const eventsForKey = this.annotationsByKey[key];
+        if (eventsForKey) {
+            eventsForKey.delete(event);
+
+            // Re-sort the [key, events] pairs in descending order of event count
+            this.sortedAnnotationsByKey.sort((a, b) => {
+                const aEvents = a[1];
+                const bEvents = b[1];
+                return bEvents.size - aEvents.size;
+            });
+        }
+
+        const sender = event.getSender()!;
+        const eventsFromSender = this.annotationsBySender[sender];
+        if (eventsFromSender) {
+            eventsFromSender.delete(event);
+        }
+    }
+
+    /**
+     * For relations that have been redacted, we want to remove them from
+     * aggregation data sets and emit an update event.
+     *
+     * To do so, we listen for `Event.beforeRedaction`, which happens:
+     *   - after the server accepted the redaction and remote echoed back to us
+     *   - before the original event has been marked redacted in the client
+     *
+     * @param redactedEvent - The original relation event that is about to be redacted.
+     */
+    private onBeforeRedaction = async (redactedEvent: MatrixEvent): Promise<void> => {
+        if (!this.relations.has(redactedEvent)) {
+            return;
+        }
+
+        this.relations.delete(redactedEvent);
+
+        if (this.relationType === RelationType.Annotation) {
+            // Remove the redacted annotation from aggregation by key
+            this.removeAnnotationFromAggregation(redactedEvent);
+        } else if (this.relationType === RelationType.Replace && this.targetEvent && !this.targetEvent.isState()) {
+            const lastReplacement = await this.getLastReplacement();
+            this.targetEvent.makeReplaced(lastReplacement!);
+        }
+
+        redactedEvent.removeListener(MatrixEventEvent.BeforeRedaction, this.onBeforeRedaction);
+
+        this.emit(RelationsEvent.Redaction, redactedEvent);
+    };
+
+    /**
+     * Get all events in this collection grouped by key and sorted by descending
+     * event count in each group.
+     *
+     * This is currently only supported for the annotation relation type.
+     *
+     * An array of [key, events] pairs sorted by descending event count.
+     * The events are stored in a Set (which preserves insertion order).
+     */
+    public getSortedAnnotationsByKey(): [string, Set<MatrixEvent>][] | null {
+        if (this.relationType !== RelationType.Annotation) {
+            // Other relation types are not grouped currently.
+            return null;
+        }
+
+        return this.sortedAnnotationsByKey;
+    }
+
+    /**
+     * Get all events in this collection grouped by sender.
+     *
+     * This is currently only supported for the annotation relation type.
+     *
+     * An object with each relation sender as a key and the matching Set of
+     * events for that sender as a value.
+     */
+    public getAnnotationsBySender(): Record<string, Set<MatrixEvent>> | null {
+        if (this.relationType !== RelationType.Annotation) {
+            // Other relation types are not grouped currently.
+            return null;
+        }
+
+        return this.annotationsBySender;
+    }
+
+    /**
+     * Returns the most recent (and allowed) m.replace relation, if any.
+     *
+     * This is currently only supported for the m.replace relation type,
+     * once the target event is known, see `addEvent`.
+     */
+    public async getLastReplacement(): Promise<MatrixEvent | null> {
+        if (this.relationType !== RelationType.Replace) {
+            // Aggregating on last only makes sense for this relation type
+            return null;
+        }
+        if (!this.targetEvent) {
+            // Don't know which replacements to accept yet.
+            // This method shouldn't be called before the original
+            // event is known anyway.
+            return null;
+        }
+
+        // the all-knowning server tells us that the event at some point had
+        // this timestamp for its replacement, so any following replacement should definitely not be less
+        const replaceRelation = this.targetEvent.getServerAggregatedRelation<IAggregatedRelation>(RelationType.Replace);
+        const minTs = replaceRelation?.origin_server_ts;
+
+        const lastReplacement = this.getRelations().reduce<MatrixEvent | null>((last, event) => {
+            if (event.getSender() !== this.targetEvent!.getSender()) {
+                return last;
+            }
+            if (minTs && minTs > event.getTs()) {
+                return last;
+            }
+            if (last && last.getTs() > event.getTs()) {
+                return last;
+            }
+            return event;
+        }, null);
+
+        if (lastReplacement?.shouldAttemptDecryption() && this.client.isCryptoEnabled()) {
+            await lastReplacement.attemptDecryption(this.client.crypto!);
+        } else if (lastReplacement?.isBeingDecrypted()) {
+            await lastReplacement.getDecryptionPromise();
+        }
+
+        return lastReplacement;
+    }
+
+    /*
+     * @param targetEvent - the event the relations are related to.
+     */
+    public async setTargetEvent(event: MatrixEvent): Promise<void> {
+        if (this.targetEvent) {
+            return;
+        }
+        this.targetEvent = event;
+
+        if (this.relationType === RelationType.Replace && !this.targetEvent.isState()) {
+            const replacement = await this.getLastReplacement();
+            // this is the initial update, so only call it if we already have something
+            // to not emit Event.replaced needlessly
+            if (replacement) {
+                this.targetEvent.makeReplaced(replacement);
+            }
+        }
+
+        this.maybeEmitCreated();
+    }
+
+    private maybeEmitCreated(): void {
+        if (this.creationEmitted) {
+            return;
+        }
+        // Only emit we're "created" once we have a target event instance _and_
+        // at least one related event.
+        if (!this.targetEvent || !this.relations.size) {
+            return;
+        }
+        this.creationEmitted = true;
+        this.targetEvent.emit(MatrixEventEvent.RelationsCreated, this.relationType, this.eventType);
+    }
+}