From 61445d3d87169011a6c317f710737bb7e4090aee Mon Sep 17 00:00:00 2001
From: Julian Lam <julian@nodebb.org>
Date: Thu, 17 Oct 2024 11:05:27 -0400
Subject: [PATCH] feat: send Update(Note) on chat message deletion and
 restoration, serving Tombstone if deleted

re: #12853
---
 src/activitypub/inbox.js | 13 +++++++++++--
 src/activitypub/mocks.js | 14 ++++++++++++--
 src/api/activitypub.js   | 12 +++++++++---
 src/messaging/delete.js  |  4 ++++
 4 files changed, 36 insertions(+), 7 deletions(-)

diff --git a/src/activitypub/inbox.js b/src/activitypub/inbox.js
index 90ed9d6a22..ed33d00e90 100644
--- a/src/activitypub/inbox.js
+++ b/src/activitypub/inbox.js
@@ -107,8 +107,11 @@ inbox.update = async (req) => {
 					}
 
 					case isMessage: {
-						const roomId = await messaging.getMessageField(object.id, 'roomId');
+						const [roomId, deleted] = await messaging.getMessageFields(object.id, ['roomId', 'deleted']);
 						await messaging.editMessage(actor, object.id, roomId, object.content);
+						if (deleted) {
+							await api.chats.restoreMessage({ uid: actor }, { mid: object.id });
+						}
 						break;
 					}
 
@@ -140,8 +143,9 @@ inbox.update = async (req) => {
 		}
 
 		case 'Tombstone': {
-			const [isNote/* , isActor */] = await Promise.all([
+			const [isNote, isMessage/* , isActor */] = await Promise.all([
 				posts.exists(object.id),
+				messaging.messageExists(object.id),
 				// db.isSortedSetMember('usersRemote:lastCrawled', object.id),
 			]);
 
@@ -151,6 +155,11 @@ inbox.update = async (req) => {
 					break;
 				}
 
+				case isMessage: {
+					await api.chats.deleteMessage({ uid: actor }, { mid: object.id });
+					break;
+				}
+
 				// case isActor: {
 				// console.log('actor');
 				// break;
diff --git a/src/activitypub/mocks.js b/src/activitypub/mocks.js
index 90ba7b478d..09f6eeb934 100644
--- a/src/activitypub/mocks.js
+++ b/src/activitypub/mocks.js
@@ -451,10 +451,20 @@ Mocks.notes.public = async (post) => {
 };
 
 Mocks.notes.private = async ({ messageObj }) => {
-	// todo: deleted messages
+	const id = `${nconf.get('url')}/message/${messageObj.mid}`;
+
+	// Return a tombstone for a deleted message
+	if (messageObj.deleted === 1) {
+		return Mocks.tombstone({
+			id,
+			formerType: 'Note',
+			attributedTo: `${nconf.get('url')}/uid/${messageObj.fromuid}`,
+			// context: `${nconf.get('url')}/topic/${post.topic.tid}`,
+		});
+	}
+
 	let uids = await messaging.getUidsInRoom(messageObj.roomId, 0, -1);
 	uids = uids.filter(uid => String(uid) !== String(messageObj.fromuid)); // no author
-	const id = `${nconf.get('url')}/message/${messageObj.mid}`;
 	const to = new Set(uids.map(uid => (utils.isNumber(uid) ? `${nconf.get('url')}/uid/${uid}` : uid)));
 	const published = messageObj.timestampISO;
 	const updated = messageObj.edited ? messageObj.editedISO : undefined;
diff --git a/src/api/activitypub.js b/src/api/activitypub.js
index db4493f565..24a8504bb2 100644
--- a/src/api/activitypub.js
+++ b/src/api/activitypub.js
@@ -288,16 +288,22 @@ activitypubApi.update.note = enabledCheck(async (caller, { post }) => {
 });
 
 activitypubApi.update.privateNote = enabledCheck(async (caller, { messageObj }) => {
+	if (!utils.isNumber(messageObj.mid)) {
+		return;
+	}
+
 	const { roomId } = messageObj;
-	let targets = await messaging.getUidsInRoom(roomId, 0, -1);
-	targets = targets.filter(uid => !utils.isNumber(uid)); // remote uids only
+	let uids = await messaging.getUidsInRoom(roomId, 0, -1);
+	uids = uids.filter(uid => String(uid) !== String(messageObj.fromuid)); // no author
+	const to = uids.map(uid => (utils.isNumber(uid) ? `${nconf.get('url')}/uid/${uid}` : uid));
+	const targets = uids.filter(uid => !utils.isNumber(uid)); // remote uids only
 
 	const object = await activitypub.mocks.notes.private({ messageObj });
 
 	const payload = {
 		id: `${object.id}#activity/create/${Date.now()}`,
 		type: 'Update',
-		to: object.to,
+		to,
 		object,
 	};
 
diff --git a/src/messaging/delete.js b/src/messaging/delete.js
index 1c16ceddc1..9e0f23c797 100644
--- a/src/messaging/delete.js
+++ b/src/messaging/delete.js
@@ -2,6 +2,7 @@
 
 const sockets = require('../socket.io');
 const plugins = require('../plugins');
+const api = require('../api');
 
 module.exports = function (Messaging) {
 	Messaging.deleteMessage = async (mid, uid) => await doDeleteRestore(mid, 1, uid);
@@ -18,6 +19,7 @@ module.exports = function (Messaging) {
 
 		await Messaging.setMessageField(mid, 'deleted', state);
 		msgData.deleted = state;
+
 		const ioRoom = sockets.in(`chat_room_${msgData.roomId}`);
 		if (state === 1 && ioRoom) {
 			ioRoom.emit('event:chats.delete', mid);
@@ -27,5 +29,7 @@ module.exports = function (Messaging) {
 			ioRoom.emit('event:chats.restore', messages[0]);
 			plugins.hooks.fire('action:messaging.restore', { message: msgData });
 		}
+
+		api.activitypub.update.privateNote({ uid }, { messageObj: msgData });
 	}
 };