Deduplicate PaymentReceived events on restart

src/event.rs

@@ -358,6 +358,14 @@ where
 		Ok(())
 	}
 
+	/// Check if a PaymentReceived event with the given payment_id already exists in the queue.
+	pub(crate) fn contains_payment_received(&self, payment_id: &PaymentId) -> bool {
+		let locked_queue = self.queue.lock().unwrap();
+		locked_queue.iter().any(|event| {
+			matches!(event, Event::PaymentReceived { payment_id: Some(id), .. } if id == payment_id)
+		})
+	}
+
 	fn persist_queue(&self, locked_queue: &VecDeque<Event>) -> Result<(), Error> {
 		let data = EventQueueSerWrapper(locked_queue).encode();
 		self.kv_store
@@ -938,6 +946,18 @@ where
 					},
 				}
 
+				// Check if a PaymentReceived event for this payment already exists in the queue.
+				// This handles the case where PaymentClaimed is replayed on restart - we only
+				// want to queue one PaymentReceived event per payment.
+				if self.event_queue.contains_payment_received(&payment_id) {
+					log_debug!(
+						self.logger,
+						"Skipping duplicate PaymentReceived for payment {}: event already queued",
+						payment_id,
+					);
+					return Ok(());
+				}
+
 				let event = Event::PaymentReceived {
 					payment_id: Some(payment_id),
 					payment_hash,