From e32a265836bfd59d4e3e11c5711c11612913f903 Mon Sep 17 00:00:00 2001
From: Siyuan Miao <i@xswan.net>
Date: Fri, 12 Sep 2025 12:48:34 +0200
Subject: [PATCH] fix: handshake won't happen if webrtc reconnects

---
 hidrpc.go                 |  5 ++++-
 ui/src/hooks/stores.ts    |  4 ++--
 ui/src/hooks/useHidRpc.ts | 14 ++++++++++++++
 3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/hidrpc.go b/hidrpc.go
index 8233e0f4..a81e115a 100644
--- a/hidrpc.go
+++ b/hidrpc.go
@@ -134,7 +134,10 @@ func reportHidRPC(params any, session *Session) {
 	}
 
 	if !session.hidRPCAvailable || session.HidChannel == nil {
-		logger.Warn().Msg("HID RPC is not available, skipping reportHidRPC")
+		logger.Warn().
+			Bool("hidRPCAvailable", session.hidRPCAvailable).
+			Bool("HidChannel", session.HidChannel != nil).
+			Msg("HID RPC is not available, skipping reportHidRPC")
 		return
 	}
 
diff --git a/ui/src/hooks/stores.ts b/ui/src/hooks/stores.ts
index b6eebfc0..bfbbb26e 100644
--- a/ui/src/hooks/stores.ts
+++ b/ui/src/hooks/stores.ts
@@ -109,7 +109,7 @@ export interface RTCState {
   setHidRpcDisabled: (disabled: boolean) => void;
 
   rpcHidProtocolVersion: number | null;
-  setRpcHidProtocolVersion: (version: number) => void;
+  setRpcHidProtocolVersion: (version: number | null) => void;
 
   rpcHidChannel: RTCDataChannel | null;
   setRpcHidChannel: (channel: RTCDataChannel) => void;
@@ -170,7 +170,7 @@ export const useRTCStore = create<RTCState>(set => ({
   setHidRpcDisabled: (disabled: boolean) => set({ hidRpcDisabled: disabled }),
 
   rpcHidProtocolVersion: null,
-  setRpcHidProtocolVersion: (version: number) => set({ rpcHidProtocolVersion: version }),
+  setRpcHidProtocolVersion: (version: number | null) => set({ rpcHidProtocolVersion: version }),
 
   rpcHidChannel: null,
   setRpcHidChannel: (channel: RTCDataChannel) => set({ rpcHidChannel: channel }),
diff --git a/ui/src/hooks/useHidRpc.ts b/ui/src/hooks/useHidRpc.ts
index 6f75c5ae..57a54e96 100644
--- a/ui/src/hooks/useHidRpc.ts
+++ b/ui/src/hooks/useHidRpc.ts
@@ -192,10 +192,24 @@ export function useHidRpc(onHidRpcMessage?: (payload: RpcMessage) => void) {
       onHidRpcMessage?.(message);
     };
 
+    const openHandler = () => {
+      console.warn("HID RPC channel opened");
+      sendHandshake();
+    };
+
+    const closeHandler = () => {
+      console.warn("HID RPC channel closed");
+      setRpcHidProtocolVersion(null);
+    };
+
     rpcHidChannel.addEventListener("message", messageHandler);
+    rpcHidChannel.addEventListener("close", closeHandler);
+    rpcHidChannel.addEventListener("open", openHandler);
 
     return () => {
       rpcHidChannel.removeEventListener("message", messageHandler);
+      rpcHidChannel.removeEventListener("close", closeHandler);
+      rpcHidChannel.removeEventListener("open", openHandler);
     };
   },
     [