From b1344538013d735a50ef9168208cb2cd60735f19 Mon Sep 17 00:00:00 2001
From: Tulir Asokan <tulir@maunium.net>
Date: Fri, 23 Feb 2024 20:25:31 +0200
Subject: [PATCH] Handle logout events in a hacky way

---
 bridgestate.go         | 2 ++
 libgm/event_handler.go | 7 +++++++
 libgm/events/ready.go  | 2 ++
 user.go                | 7 +++++++
 4 files changed, 18 insertions(+)

diff --git a/bridgestate.go b/bridgestate.go
index 3243221..c76a2f2 100644
--- a/bridgestate.go
+++ b/bridgestate.go
@@ -27,6 +27,7 @@ const (
 	GMListenError      status.BridgeStateErrorCode = "gm-listen-error"
 	GMFatalError       status.BridgeStateErrorCode = "gm-listen-fatal-error"
 	GMUnpaired         status.BridgeStateErrorCode = "gm-unpaired"
+	GMUnpairedGaia     status.BridgeStateErrorCode = "gm-unpaired-gaia"
 	GMUnpaired404      status.BridgeStateErrorCode = "gm-unpaired-entity-not-found"
 	GMNotConnected     status.BridgeStateErrorCode = "gm-not-connected"
 	GMConnecting       status.BridgeStateErrorCode = "gm-connecting"
@@ -49,6 +50,7 @@ func init() {
 		GMFatalError:                "Fatal error polling messages from Google Messages server, please re-link the bridge",
 		GMUnpaired:                  "Unpaired from Google Messages, please re-link the connection to continue using SMS/RCS",
 		GMUnpaired404:               "Unpaired from Google Messages, please re-link the connection to continue using SMS/RCS",
+		GMUnpairedGaia:              "Unpaired from Google Messages, please re-link the connection to continue using SMS/RCS",
 		GMNotDefaultSMSApp:          "Google Messages isn't set as the default SMS app. Please set the default SMS app on your Android phone to Google Messages to continue using SMS/RCS.",
 		GMBrowserInactive:           "Google Messages opened in another browser",
 		GMBrowserInactiveTimeout:    "Google Messages disconnected due to timeout",
diff --git a/libgm/event_handler.go b/libgm/event_handler.go
index 61711ea..714ae38 100644
--- a/libgm/event_handler.go
+++ b/libgm/event_handler.go
@@ -1,6 +1,7 @@
 package libgm
 
 import (
+	"bytes"
 	"crypto/sha256"
 	"encoding/base64"
 	"fmt"
@@ -203,9 +204,15 @@ type WrappedMessage struct {
 	Data  []byte
 }
 
+var hackyLoggedOutBytes = []byte{0x72, 0x00}
+
 func (c *Client) handleUpdatesEvent(msg *IncomingRPCMessage) {
 	switch msg.Message.Action {
 	case gmproto.ActionType_GET_UPDATES:
+		if msg.DecryptedData == nil && bytes.Equal(msg.Message.UnencryptedData, hackyLoggedOutBytes) {
+			c.triggerEvent(&events.GaiaLoggedOut{})
+			return
+		}
 		data, ok := msg.DecryptedMessage.(*gmproto.UpdateEvents)
 		if !ok {
 			c.Logger.Error().
diff --git a/libgm/events/ready.go b/libgm/events/ready.go
index 67a1c7c..0f7cb77 100644
--- a/libgm/events/ready.go
+++ b/libgm/events/ready.go
@@ -15,6 +15,8 @@ type ClientReady struct {
 
 type AuthTokenRefreshed struct{}
 
+type GaiaLoggedOut struct{}
+
 type AccountChange struct {
 	*gmproto.AccountChangeOrSomethingEvent
 	IsFake bool
diff --git a/user.go b/user.go
index 5535ee7..728e595 100644
--- a/user.go
+++ b/user.go
@@ -711,6 +711,13 @@ func (user *User) syncHandleEvent(event any) {
 			Error:      GMUnpaired,
 		}, false)
 		go user.sendMarkdownBridgeAlert(true, "Unpaired from Google Messages. Log in again to continue using the bridge.")
+	case *events.GaiaLoggedOut:
+		user.zlog.Info().Msg("Got gaia logout event")
+		go user.Logout(status.BridgeState{
+			StateEvent: status.StateBadCredentials,
+			Error:      GMUnpaired,
+		}, false)
+		go user.sendMarkdownBridgeAlert(true, "Unpaired from Google Messages. Log in again to continue using the bridge.")
 	case *events.AuthTokenRefreshed:
 		go func() {
 			err := user.Update(context.TODO())