From 247c1a3340d6d8bc1d3e47b68c44e6a05730a09f Mon Sep 17 00:00:00 2001
From: GitHub Copilot <copilot@github.com>
Date: Wed, 18 Feb 2026 15:09:31 +0000
Subject: [PATCH] Fix idle session breaking resize and input on reconnect
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Two bugs introduced in the idle tracker pause commit:

1. handleOutput() short-circuited entirely when idle, skipping
   connector.OnData() — so terminal output never reached clients
   even after reconnecting. Fix: still call connector.OnData()
   during idle; only skip the expensive tracker.Feed().

2. When a WebSocket client reconnects to an existing session,
   handleWebSocket never called UpdateConnector(), so the idle
   flag was never cleared and the tracker stayed paused. Fix:
   create a fresh connector and call session.UpdateConnector()
   on reconnect, which clears idle and rebuilds the tracker.
---
 webterm/coverage_boost_test.go | 23 ++++++++++++-----------
 webterm/docker_exec_session.go |  1 +
 webterm/server.go              |  7 +++++++
 webterm/terminal_session.go    |  5 ++++-
 4 files changed, 24 insertions(+), 12 deletions(-)

diff --git a/webterm/coverage_boost_test.go b/webterm/coverage_boost_test.go
index b50a31e..b7193b8 100644
--- a/webterm/coverage_boost_test.go
+++ b/webterm/coverage_boost_test.go
@@ -791,17 +791,18 @@ t.Fatalf("replay mismatch: %q", got)
 s.MarkIdle()
 s.idleSince.Store(time.Now().Add(-idleTrackerThreshold - time.Second).UnixNano())
 
-// Feed more output while idle — only replay should update
-s.handleOutput([]byte(" world"))
-if got := string(s.GetReplayBuffer()); got != "hello world" {
-t.Fatalf("replay should accumulate while idle: %q", got)
-}
-conn.mu.Lock()
-idleData := len(conn.data)
-conn.mu.Unlock()
-if idleData != 1 {
-t.Fatalf("connector should NOT receive data while idle, got %d calls", idleData)
-}
+	// Feed more output while idle — replay and connector still receive data,
+	// but the VT parser (tracker) is skipped.
+	s.handleOutput([]byte(" world"))
+	if got := string(s.GetReplayBuffer()); got != "hello world" {
+		t.Fatalf("replay should accumulate while idle: %q", got)
+	}
+	conn.mu.Lock()
+	idleData := len(conn.data)
+	conn.mu.Unlock()
+	if idleData != 2 {
+		t.Fatalf("connector should still receive data while idle, got %d calls", idleData)
+	}
 
 // GetScreenSnapshot should rebuild tracker on-demand
 snap2 := s.GetScreenSnapshot()
diff --git a/webterm/docker_exec_session.go b/webterm/docker_exec_session.go
index fc18353..393f112 100644
--- a/webterm/docker_exec_session.go
+++ b/webterm/docker_exec_session.go
@@ -154,6 +154,7 @@ func (s *DockerExecSession) handleOutput(data []byte) {
 	if ts := s.idleSince.Load(); ts != 0 && time.Since(time.Unix(0, ts)) > idleTrackerThreshold {
 		if len(filtered) > 0 {
 			s.replay.Add(filtered)
+			connector.OnData(filtered)
 		}
 		return
 	}
diff --git a/webterm/server.go b/webterm/server.go
index 9eab210..d4df423 100644
--- a/webterm/server.go
+++ b/webterm/server.go
@@ -515,6 +515,13 @@ func (s *LocalServer) handleWebSocket(w http.ResponseWriter, r *http.Request) {
 		session := s.sessionManager.GetSession(sessionID)
 		if session != nil && session.IsRunning() {
 			sessionCreated = true
+			// Clear idle state so the output pipeline resumes fully
+			connector := &localClientConnector{
+				server:    s,
+				sessionID: sessionID,
+				routeKey:  routeKey,
+			}
+			session.UpdateConnector(connector)
 			replay := daResponsePattern.ReplaceAll(session.GetReplayBuffer(), nil)
 			if len(replay) > 0 {
 				s.enqueueWSFrame(routeKey, websocket.BinaryMessage, replay)
diff --git a/webterm/terminal_session.go b/webterm/terminal_session.go
index 4c4b377..9d716e8 100644
--- a/webterm/terminal_session.go
+++ b/webterm/terminal_session.go
@@ -146,9 +146,12 @@ func (s *TerminalSession) handleOutput(data []byte) {
 	s.mu.Unlock()
 	filtered = FilterUnsupportedModes(filtered)
 	if ts := s.idleSince.Load(); ts != 0 && time.Since(time.Unix(0, ts)) > idleTrackerThreshold {
-		// No client connected — only maintain the replay buffer.
+		// No client connected — maintain replay buffer but skip VT parser.
+		// Still call the connector so data flows if a client just reconnected
+		// before MarkIdle was cleared.
 		if len(filtered) > 0 {
 			s.replay.Add(filtered)
+			connector.OnData(filtered)
 		}
 		return
 	}