From b93100413c113b24d8652655579682f92e68dd50 Mon Sep 17 00:00:00 2001
From: Pierre HUBERT <pierre.git@communiquons.org>
Date: Mon, 1 Dec 2025 10:12:11 +0100
Subject: [PATCH] Propagate read receipt events

---
 matrixgw_backend/src/broadcast_messages.rs    |  3 ++
 .../src/controllers/ws_controller.rs          | 35 +++++++++++++++++++
 .../src/matrix_connection/sync_thread.rs      | 17 ++++++++-
 matrixgw_frontend/src/api/WsApi.ts            | 16 ++++++++-
 4 files changed, 69 insertions(+), 2 deletions(-)

diff --git a/matrixgw_backend/src/broadcast_messages.rs b/matrixgw_backend/src/broadcast_messages.rs
index db34a75..2e129eb 100644
--- a/matrixgw_backend/src/broadcast_messages.rs
+++ b/matrixgw_backend/src/broadcast_messages.rs
@@ -2,6 +2,7 @@ use crate::matrix_connection::sync_thread::MatrixSyncTaskID;
 use crate::users::{APIToken, UserEmail};
 use matrix_sdk::Room;
 use matrix_sdk::ruma::events::reaction::OriginalSyncReactionEvent;
+use matrix_sdk::ruma::events::receipt::SyncReceiptEvent;
 use matrix_sdk::ruma::events::room::message::OriginalSyncRoomMessageEvent;
 use matrix_sdk::ruma::events::room::redaction::OriginalSyncRoomRedactionEvent;
 use matrix_sdk::sync::SyncResponse;
@@ -32,6 +33,8 @@ pub enum BroadcastMessage {
     ReactionEvent(BxRoomEvent<OriginalSyncReactionEvent>),
     /// New room redaction
     RoomRedactionEvent(BxRoomEvent<OriginalSyncRoomRedactionEvent>),
+    /// Message fully read event
+    ReceiptEvent(BxRoomEvent<SyncReceiptEvent>),
     /// Raw Matrix sync response
     MatrixSyncResponse { user: UserEmail, sync: SyncResponse },
 }
diff --git a/matrixgw_backend/src/controllers/ws_controller.rs b/matrixgw_backend/src/controllers/ws_controller.rs
index 0c0fab1..62553e7 100644
--- a/matrixgw_backend/src/controllers/ws_controller.rs
+++ b/matrixgw_backend/src/controllers/ws_controller.rs
@@ -29,6 +29,19 @@ pub struct WsRoomEvent<E> {
     pub data: Box<E>,
 }
 
+#[derive(Debug, serde::Serialize)]
+pub struct WsReceiptEntry {
+    event: OwnedEventId,
+    user: OwnedUserId,
+    ts: Option<MilliSecondsSinceUnixEpoch>,
+}
+
+#[derive(Debug, serde::Serialize)]
+pub struct WsReceiptEvent {
+    pub room_id: OwnedRoomId,
+    pub receipts: Vec<WsReceiptEntry>,
+}
+
 /// Messages sent to the client
 #[derive(Debug, serde::Serialize)]
 #[serde(tag = "type")]
@@ -41,6 +54,9 @@ pub enum WsMessage {
 
     /// Room reaction event
     RoomRedactionEvent(WsRoomEvent<RoomRedactionEventContent>),
+
+    /// Fully read message event
+    ReceiptEvent(WsReceiptEvent),
 }
 
 impl WsMessage {
@@ -73,6 +89,25 @@ impl WsMessage {
                     data: Box::new(evt.data.content.clone()),
                 }))
             }
+            BroadcastMessage::ReceiptEvent(evt) if &evt.user == user => {
+                let mut receipts = vec![];
+                for (event_id, r) in &evt.data.content.0 {
+                    for user_receipts in r.values() {
+                        for (user, receipt) in user_receipts {
+                            receipts.push(WsReceiptEntry {
+                                event: event_id.clone(),
+                                user: user.clone(),
+                                ts: receipt.ts,
+                            })
+                        }
+                    }
+                }
+
+                Some(Self::ReceiptEvent(WsReceiptEvent {
+                    room_id: evt.room.room_id().to_owned(),
+                    receipts,
+                }))
+            }
             _ => None,
         }
     }
diff --git a/matrixgw_backend/src/matrix_connection/sync_thread.rs b/matrixgw_backend/src/matrix_connection/sync_thread.rs
index 30f4307..439c753 100644
--- a/matrixgw_backend/src/matrix_connection/sync_thread.rs
+++ b/matrixgw_backend/src/matrix_connection/sync_thread.rs
@@ -8,6 +8,7 @@ use crate::matrix_connection::matrix_manager::MatrixManagerMsg;
 use futures_util::StreamExt;
 use matrix_sdk::Room;
 use matrix_sdk::ruma::events::reaction::OriginalSyncReactionEvent;
+use matrix_sdk::ruma::events::receipt::SyncReceiptEvent;
 use matrix_sdk::ruma::events::room::message::OriginalSyncRoomMessageEvent;
 use matrix_sdk::ruma::events::room::redaction::OriginalSyncRoomRedactionEvent;
 use ractor::ActorRef;
@@ -91,11 +92,25 @@ async fn sync_thread_task(
                     room,
                 }))
             {
-                log::warn!("Failed to forward reaction event! {e}");
+                log::warn!("Failed to forward redaction event! {e}");
             }
         },
     ));
 
+    let tx_receipt_handle = tx.clone();
+    let user_receipt_handle = client.email.clone();
+    handlers.push(
+        client.add_event_handler(async move |event: SyncReceiptEvent, room: Room| {
+            if let Err(e) = tx_receipt_handle.send(BroadcastMessage::ReceiptEvent(BxRoomEvent {
+                user: user_receipt_handle.clone(),
+                data: Box::new(event),
+                room,
+            })) {
+                log::warn!("Failed to forward receipt event! {e}");
+            }
+        }),
+    );
+
     loop {
         tokio::select! {
             // Message from tokio broadcast
diff --git a/matrixgw_frontend/src/api/WsApi.ts b/matrixgw_frontend/src/api/WsApi.ts
index 23eb2f3..6104170 100644
--- a/matrixgw_frontend/src/api/WsApi.ts
+++ b/matrixgw_frontend/src/api/WsApi.ts
@@ -45,10 +45,24 @@ export interface RoomRedactionEvent extends BaseRoomEvent {
   };
 }
 
+export interface ReceiptEventEntry {
+  event: string;
+  user: string;
+  ts?: number;
+}
+
+export interface RoomReceiptEvent {
+  time: number;
+  type: "ReceiptEvent";
+  room_id: string;
+  receipts: ReceiptEventEntry[];
+}
+
 export type WsMessage =
   | RoomMessageEvent
   | RoomReactionEvent
-  | RoomRedactionEvent;
+  | RoomRedactionEvent
+  | RoomReceiptEvent;
 
 export class WsApi {
   /**