fix: Filter DeleteMessage when computing the oldest loaded message [WPB-3506]

src/script/conversation/MessageRepository.ts

@@ -1120,7 +1120,7 @@ export class MessageRepository {
    */
   public async deleteMessageById(conversationEntity: Conversation, messageId: string): Promise<number> {
     const isLastDeleted =
-      conversationEntity.isShowingLastReceivedMessage() && conversationEntity.getNewestMessage()?.id === messageId;
+      conversationEntity.hasLastReceivedMessageLoaded() && conversationEntity.getNewestMessage()?.id === messageId;
 
     const deleteCount = await this.eventService.deleteEvent(conversationEntity.id, messageId);
     const previousMessage = conversationEntity.getNewestMessage();

src/script/entity/Conversation.ts

@@ -58,7 +58,7 @@ import {ConversationStatus} from '../conversation/ConversationStatus';
 import {ConversationVerificationState} from '../conversation/ConversationVerificationState';
 import {NOTIFICATION_STATE} from '../conversation/NotificationSetting';
 import {ConversationError} from '../error/ConversationError';
-import {isContentMessage} from '../guards/Message';
+import {isContentMessage, isDeleteMessage} from '../guards/Message';
 import {StatusType} from '../message/StatusType';
 import {ConversationRecord} from '../storage/record/ConversationRecord';
 import {TeamState} from '../team/TeamState';
@@ -689,11 +689,13 @@ export class Conversation {
       if (alreadyAdded) {
         return false;
       }
-      if (this.isShowingLastReceivedMessage()) {
+      if (this.hasLastReceivedMessageLoaded()) {
         this.updateTimestamps(messageEntity);
         this.incomingMessages.remove(({id}) => messageEntity.id === id);
+        // If the last received message is currently in memory, we can add this message to the displayed messages
         this.messages_unordered.push(messageEntity);
       } else {
+        // If the conversation is not loaded, we will add this message to the incoming messages (but not to the messages displayed)
         this.incomingMessages.push(messageEntity);
       }
       amplify.publish(WebAppEvents.CONVERSATION.MESSAGE.ADDED, messageEntity);
@@ -917,10 +919,14 @@ export class Conversation {
   }
 
   /**
-   * Get the first message of the conversation.
+   * Get the oldest loaded message of the conversation.
    */
   getOldestMessage(): Message | undefined {
-    return this.messages()[0];
+    return this.messages().find(
+      message =>
+        // Deleted message should be ignored since they might have a timestamp in the past (the timestamp of a delete message is the timestamp of the message that was deleted)
+        !isDeleteMessage(message),
+    );
   }
 
   /**
@@ -1018,10 +1024,9 @@ export class Conversation {
     return participantCount <= config.MAX_VIDEO_PARTICIPANTS;
   }
 
-  readonly isShowingLastReceivedMessage = (): boolean => {
-    return this.getNewestMessage()?.timestamp()
-      ? this.getNewestMessage().timestamp() >= this.last_event_timestamp()
-      : true;
+  readonly hasLastReceivedMessageLoaded = (): boolean => {
+    const newestMessage = this.getNewestMessage();
+    return newestMessage?.timestamp() ? newestMessage.timestamp() >= this.last_event_timestamp() : true;
   };
 
   serialize(): ConversationRecord {

src/script/guards/Message.ts

@@ -20,6 +20,7 @@
 import {Draft} from 'Util/DraftStateUtil';
 
 import {ContentMessage} from '../entity/message/ContentMessage';
+import {DeleteMessage} from '../entity/message/DeleteMessage';
 import {MemberMessage} from '../entity/message/MemberMessage';
 import {SuperType} from '../message/SuperType';
 
@@ -31,6 +32,9 @@ export const isReadableMessage = (message: any): message is ContentMessage =>
 export const isContentMessage = (message: any): message is ContentMessage =>
   message && 'super_type' in message && message.super_type === SuperType.CONTENT;
 
+export const isDeleteMessage = (message: any): message is DeleteMessage =>
+  message && 'super_type' in message && message.super_type === SuperType.DELETE;
+
 export const isMemberMessage = (message: any | undefined | null): message is MemberMessage =>
   message && 'super_type' in message && message.super_type === SuperType.MEMBER;