From 988fbd9dbd0721c534f33cf49166831e0de68c51 Mon Sep 17 00:00:00 2001
From: jjangddu <dw.jang@medithings.co.kr>
Date: Thu, 23 Apr 2026 14:09:16 +0900
Subject: [PATCH] =?UTF-8?q?fix:=20watchdog=EC=9D=84=20=EB=B3=84=EB=8F=84?=
 =?UTF-8?q?=20Thread=EB=A1=9C=20=EB=B6=84=EB=A6=AC=20(handler=20=EB=B8=94?=
 =?UTF-8?q?=EB=A1=9C=ED=82=B9=20=EB=B0=A9=EC=A7=80)?=
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기존: handler.postDelayed로 watchdog 실행 → BLE 스택이 handler를
블로킹하면 watchdog도 멈춤 (좀비 상태 감지 불가)

변경: 별도 daemon Thread에서 5초마다 lastRxTimestamp 체크
→ BLE handler가 블로킹되어도 독립적으로 15초 타임아웃 감지
→ 감지 시 handler.post로 메인 스레드에서 forceDisconnectAndReconnect 실행

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 .../medilightv2android/ble/BleManager.kt      | 36 +++++++++++--------
 1 file changed, 22 insertions(+), 14 deletions(-)

diff --git a/app/src/main/java/com/example/medilightv2android/ble/BleManager.kt b/app/src/main/java/com/example/medilightv2android/ble/BleManager.kt
index d96607b..f9a4f0e 100644
--- a/app/src/main/java/com/example/medilightv2android/ble/BleManager.kt
+++ b/app/src/main/java/com/example/medilightv2android/ble/BleManager.kt
@@ -352,31 +352,39 @@ class BleManager private constructor(private val context: Context) {
         batteryTimer = null
     }
 
-    // ── Watchdog (zombie connection detection) ──
+    // ── Watchdog (zombie connection detection, runs on separate thread) ──
+
+    private var watchdogJob: Thread? = null
+    @Volatile private var watchdogRunning = false
 
     private fun startWatchdog() {
         stopWatchdog()
         lastRxTimestamp = System.currentTimeMillis()
-        val check = object : Runnable {
-            override fun run() {
-                if (!isConnected.value) return
+        watchdogRunning = true
+
+        watchdogJob = Thread({
+            while (watchdogRunning) {
+                try { Thread.sleep(5000) } catch (_: InterruptedException) { break }
+                if (!watchdogRunning) break
+                if (!isConnected.value) continue
+
                 val silenceMs = System.currentTimeMillis() - lastRxTimestamp
                 if (silenceMs > watchdogTimeoutMs) {
-                    logw { "Watchdog: no RX for ${silenceMs}ms — forcing disconnect + reconnect" }
-                    debugLogger.error("WATCHDOG_TIMEOUT silence=${silenceMs}ms — forcing reconnect")
-                    forceDisconnectAndReconnect()
-                    return
+                    handler.post {
+                        logw { "Watchdog: no RX for ${silenceMs}ms — forcing disconnect + reconnect" }
+                        debugLogger.error("WATCHDOG_TIMEOUT silence=${silenceMs}ms — forcing reconnect")
+                        forceDisconnectAndReconnect()
+                    }
+                    break
                 }
-                handler.postDelayed(this, 5000)
             }
-        }
-        watchdogTimer = check
-        handler.postDelayed(check, 5000)
+        }, "BLE-Watchdog").also { it.isDaemon = true; it.start() }
     }
 
     private fun stopWatchdog() {
-        watchdogTimer?.let { handler.removeCallbacks(it) }
-        watchdogTimer = null
+        watchdogRunning = false
+        watchdogJob?.interrupt()
+        watchdogJob = null
     }
 
     private fun forceDisconnectAndReconnect() {