From cc6b2b2934634d94d1e2fc1452533ee0f076ef6e Mon Sep 17 00:00:00 2001
From: nexy7574 <git@nexy7574.co.uk>
Date: Mon, 13 Jan 2025 17:08:36 +0000
Subject: [PATCH] Add intentional mentions to edited messages

---
 .../features/room/message/MessageEditor.tsx   | 40 +++++++++++++++++--
 1 file changed, 37 insertions(+), 3 deletions(-)

diff --git a/src/app/features/room/message/MessageEditor.tsx b/src/app/features/room/message/MessageEditor.tsx
index 0c995030..f35f2f41 100644
--- a/src/app/features/room/message/MessageEditor.tsx
+++ b/src/app/features/room/message/MessageEditor.tsx
@@ -19,9 +19,9 @@ import {
   as,
   config,
 } from 'folds';
-import { Editor, Transforms } from 'slate';
+import {Descendant, Editor, Transforms} from 'slate';
 import { ReactEditor } from 'slate-react';
-import { IContent, MatrixEvent, RelationType, Room } from 'matrix-js-sdk';
+import {IContent, IMentions, MatrixEvent, RelationType, Room} from 'matrix-js-sdk';
 import { isKeyHotkey } from 'is-hotkey';
 import {
   AUTOCOMPLETE_PREFIXES,
@@ -42,7 +42,7 @@ import {
   toMatrixCustomHTML,
   toPlainText,
   trimCustomHtml,
-  useEditor,
+  useEditor, BlockType,
 } from '../../../components/editor';
 import { useSetting } from '../../../state/hooks/settings';
 import { settingsAtom } from '../../../state/settings';
@@ -52,6 +52,10 @@ import { AsyncStatus, useAsyncCallback } from '../../../hooks/useAsyncCallback';
 import { useMatrixClient } from '../../../hooks/useMatrixClient';
 import { getEditedEvent, trimReplyFromFormattedBody } from '../../../utils/room';
 import { mobileOrTablet } from '../../../utils/user-agent';
+import {InlineElement} from "../../../components/editor/slate";
+import {getCanonicalAliasOrRoomId, isUserId} from "../../../utils/matrix";
+import {useAtom} from "jotai/index";
+import {roomIdToReplyDraftAtomFamily} from "../../../state/room/roomInputDrafts";
 
 type MessageEditorProps = {
   roomId: string;
@@ -122,6 +126,36 @@ export const MessageEditor = as<'div', MessageEditorProps>(
           body: plainText,
         };
 
+        const userIdMentions = new Set<string>();
+        // if (replyDraft && replyDraft.userId !== mx.getUserId()) {
+        //   userIdMentions.add(replyDraft.userId);
+        // }
+        // TODO: Get the original message's reply to pick up the mention
+        let mentionsRoom = false;
+        editor.children.forEach((node: Descendant): void => {
+          if ("type" in node && node.type === BlockType.Paragraph) {
+            node.children?.forEach((child: InlineElement): void => {
+              if ("type" in child && child.type === BlockType.Mention) {
+                const mention = child;
+                if (mention.id === getCanonicalAliasOrRoomId(mx, roomId)) {
+                  mentionsRoom = true
+                } else if (isUserId(mention.id) && mention.id !== mx.getUserId()) {
+                  userIdMentions.add(mention.id)
+                }
+              }
+            })
+          }
+        })
+        const mMentions: IMentions = {}
+        if (userIdMentions.size > 0) {
+          mMentions.user_ids = Array.from(userIdMentions)
+        }
+        if(mentionsRoom) {
+          mMentions.room = true
+        }
+
+        newContent["m.mentions"] = mMentions
+
         if (!customHtmlEqualsPlainText(customHtml, plainText)) {
           newContent.format = 'org.matrix.custom.html';
           newContent.formatted_body = customHtml;