Improve thread deduplication thread process

Some threads were still holding a reference to the original thread models they were assigned to, leading to some unexpected timeline rendering

src/models/event.ts

@@ -412,9 +412,12 @@ export class MatrixEvent extends EventEmitter {
      * or in the main room timeline
      */
     public get replyInThread(): boolean {
-        const relations = this.getWireContent()["m.relates_to"];
-        return this.replyEventId
-            && relations[UNSTABLE_ELEMENT_REPLY_IN_THREAD.name];
+        const replyTo = this.getWireContent()
+            ?.["m.relates_to"]
+            ?.["m.in_reply_to"];
+        return (this.replyEventId
+            && replyTo[UNSTABLE_ELEMENT_REPLY_IN_THREAD.name])
+            || this.thread instanceof Thread;
     }
 
     /**

src/models/room.ts

@@ -1104,16 +1104,17 @@ export class Room extends EventEmitter {
      * @experimental
      */
     private dedupeThreads = (readyThread): void => {
-        const threads = Array.from(this.threads);
-        if (threads.includes(readyThread)) {
-            this.threads = new Set(threads.filter(thread => {
-                if (readyThread.id === thread.id && readyThread !== thread) {
-                    return false;
+        const deduped = Array.from(this.threads).reduce((dedupedThreads, thread) => {
+            if (dedupedThreads.has(thread.id)) {
+                dedupedThreads.get(thread.id).merge(thread);
             } else {
-                    return true;
-                }
-            }));
+                dedupedThreads.set(thread.id, thread);
             }
+
+            return dedupedThreads;
+        }, new Map<string, Thread>());
+
+        this.threads = new Set<Thread>(deduped.values());
     };
 
     /**

src/models/thread.ts

@@ -31,7 +31,7 @@ export class Thread extends EventEmitter {
     /**
      * A reference to all the events ID at the bottom of the threads
      */
-    public tail = new Set<string>();
+    public readonly tail = new Set<string>();
     private _timelineSet: EventTimelineSet;
 
     constructor(
@@ -155,7 +155,7 @@ export class Thread extends EventEmitter {
      * The number of messages in the thread
      */
     public get length(): number {
-        return this._timelineSet.getLiveTimeline().getEvents().length;
+        return this.events.length;
     }
 
     /**
@@ -163,7 +163,7 @@ export class Thread extends EventEmitter {
      */
     public get participants(): Set<string> {
         const participants = new Set<string>();
-        this._timelineSet.getLiveTimeline().getEvents().forEach(event => {
+        this.events.forEach(event => {
             participants.add(event.getSender());
         });
         return participants;
@@ -180,7 +180,18 @@ export class Thread extends EventEmitter {
      * A getter for the last event added to the thread
      */
     public get replyToEvent(): MatrixEvent {
-        const events = this._timelineSet.getLiveTimeline().getEvents();
+        const events = this.events;
         return events[events.length -1];
     }
+
+    public get events(): MatrixEvent[] {
+        return this._timelineSet.getLiveTimeline().getEvents();
+    }
+
+    public merge(thread: Thread): void {
+        thread.events.forEach(event => {
+            this.addEvent(event);
+        });
+        this.events.forEach(event => event.setThread(this));
+    }
 }

src/sync.ts

@@ -1718,11 +1718,27 @@ export class SyncApi {
      * @experimental
      */
     private processThreadEvents(room: Room, threadedEvents: MatrixEvent[]): void {
-        threadedEvents.forEach(event => {
+        threadedEvents
+            .sort((a, b) => a.getTs() - b.getTs())
+            .forEach(event => {
                 room.addThreadedEvent(event);
             });
     }
 
+    // extractRelatedEvents(event: MatrixEvent, events: MatrixEvent[], relatedEvents: MatrixEvent[] = []): MatrixEvent[] {
+    //     relatedEvents.push(event);
+
+    //     const parentEventId = event.parentEventId;
+    //     const parentEventIndex = events.findIndex(event => event.getId() === parentEventId);
+
+    //     if (parentEventIndex > -1) {
+    //         const [relatedEvent] = events.splice(parentEventIndex, 1);
+    //         return this.extractRelatedEvents(relatedEvent, events, relatedEvents);
+    //     } else {
+    //         return relatedEvents;
+    //     }
+    // }
+
     /**
      * Takes a list of timelineEvents and adds and adds to notifEvents
      * as appropriate.