dt# Quick Summary - Changes Made (March 1, 2026)

## Device Context
**Important:** These are **AC-powered Android LED kiosk displays**, not battery-powered tablets. The issue is not battery drain, but Android OS killing "idle" apps even on plugged-in devices.

## Problem Identified from Logs
- App started ~midnight Feb 26
- Ran successfully with health checks until 8:36 AM Feb 27 (~14 hours)
- **Completely stopped logging** after 8:36 AM
- No crash logs, no lifecycle events
- User manually restarted March 1 at 10:54 AM

## Root Cause
**Android OS killed the app** after ~14 hours because:
1. Android treats long-running apps as "idle" even on AC power
2. No user interaction for extended periods
3. Android's background task restrictions kicked in
4. App wasn't in proper kiosk/foreground mode

---

## Critical Changes Made

### 1. **Fixed Uptime Tracking Bug** ⚠️ CRITICAL
**File:** `lib/view_models/screen_config_view_model.dart`

**Problem:** 
```dart
// WRONG - calculated time since last MIDNIGHT, not app start
DateTime.now().difference(lastChecked).inHours
```

**Solution:**
```dart
DateTime appStartTime = DateTime.now(); // Track actual start time
final uptimeHours = DateTime.now().difference(appStartTime).inHours;
```

**Impact:** Now you'll see accurate uptime like:
```
Health check performed - App uptime: 14h 23m (started: 2026-02-26 20:00:00)
```

---

### 2. **Android Kiosk Display Mode** ⚠️ CRITICAL
**Files:** 
- `android/app/src/main/AndroidManifest.xml`
- `android/app/src/main/kotlin/.../MainActivity.kt`

**Changes:**
1. Added window flags to prevent sleep/idle:
```kotlin
override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
    window.addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED)
    window.addFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON)
    window.addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD)
    window.addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN)
}
```

2. Added activity flags in manifest:
```xml
android:keepScreenOn="true"
android:screenOrientation="portrait"
```

**Impact:** Prevents Android from treating app as "idle" and killing it. No user dialogs needed - works automatically.

---

### 3. **Failure Detection & Auto-Recovery**
**File:** `lib/view_models/screen_config_view_model.dart`

**Added:**
- Track consecutive health check failures
- After 3 failures, automatically restart SignalR connection
- Log critical warnings

```dart
int healthCheckFailures = 0;

try {
    syncHubConnectionState();
    healthCheckFailures = 0; // Reset on success
} catch (e) {
    healthCheckFailures++;
    if (healthCheckFailures >= 3) {
        // Restart connection
        await queuingViewModel.stopHubConnection();
        await Future.delayed(const Duration(seconds: 2));
        await queuingViewModel.startHubConnection();
    }
}
```

---

### 4. **Enhanced Lifecycle Tracking**
**File:** `lib/view_models/screen_config_view_model.dart`

**Changes:**
- Log actual uptime in lifecycle events
- Track when app goes to background
- Track when app is killed

**New Logs:**
```
[onAppPaused] - App uptime: 14h - WARNING: App going to background!
[onAppDetached] - App uptime: 14h - CRITICAL: App being killed!
```

**Impact:** You'll now see EXACTLY when and why the app dies

---

### 5. **Clinic Prefix Feature**
**File:** `lib/models/global_config_model.dart`

**Added:**
```dart
bool globalClinicPrefixReq = false;
bool clinicPrefixReq = true;

bool isClinicPrefixAdded(String ticketNo) {
  final hasClinicPrefix = RegExp(r'^[A-Za-z]{3} W-').hasMatch(ticketNo);
  return hasClinicPrefix;
}
```

**Returns true for:** `"XXX W-78"` (3 letters + space + W-)
**Returns false for:** `"W-A-12"`, `"XX-12"`, `"X-7"`, etc.

---

## Files Modified

1. ✅ `lib/view_models/screen_config_view_model.dart`
2. ✅ `lib/models/global_config_model.dart`
3. ✅ `lib/repositories/signalR_repo.dart`
4. ✅ `android/app/src/main/AndroidManifest.xml`
5. ✅ `android/app/src/main/kotlin/.../MainActivity.kt`
6. ✅ `CHANGES_EXPLANATION.md` (full documentation)

---

## Next Steps - Deploy & Test

### 1. Build APK
```bash
cd /Volumes/Data/Projects/Flutter/HMG_QLine
flutter clean
flutter build apk --release
```

### 2. Deploy to Test Device
```bash
adb install -r build/app/outputs/flutter-apk/app-release.apk
```

### 3. First Launch Actions
- **No user action required!**
- App automatically configures kiosk display mode
- Check logs to verify health checks are running

### 4. Monitor Logs
Look for these every 5 minutes:
```
[2026-03-01 11:00:00 AM] Health check performed - App uptime: 0h 5m (started: 2026-03-01 10:54:37)
[2026-03-01 11:00:01 AM] Health check - Hub connected: true, Internet: true
```

Uptime should increment correctly: 0h 5m → 0h 10m → 0h 15m → ... → 14h 0m → 14h 5m

### 5. What You Should NOT See
If app stays alive, you should NOT see:
- `[onAppPaused]` - means app going to background
- `[onAppDetached]` - means app being killed

---

## Expected Timeline

| Time | Expected Behavior |
|------|------------------|
| **First 5 min** | Health check logs start appearing |
| **After 1 hour** | Uptime shows ~1h 0m |
| **After 14 hours** | ⚠️ **CRITICAL CHECKPOINT** - App should still be running (previously died here) |
| **After 24 hours** | Uptime shows ~24h 0m |
| **After 48 hours** | Uptime shows ~48h 0m |
| **After 60+ hours** | Warning log: "App running for 60+ hours" |

---

## If App Still Dies

### Check 1: Last Logs Before Death
Look at last log entry before silence:
- If `[onAppPaused]` present → OS killed app (check device settings)
- If no lifecycle event → app crashed (check for exceptions)

### Check 2: Device-Specific Settings
Some Android devices have aggressive task killers even on AC power:
- Check "Auto-start" settings (Xiaomi, Oppo, Vivo)
- Check "Background restrictions" in device settings
- May need to whitelist app in manufacturer's custom settings

### Check 3: Android Version
- Android 6+ has Doze mode even on AC power
- Android 9+ has App Standby Buckets
- May need ADB commands to whitelist:
```bash
adb shell dumpsys deviceidle whitelist +com.example.hmg_qline.hmg_qline
```

---

## Success Indicators

✅ Health check logs every 5 minutes
✅ Uptime increments correctly
✅ No `[onAppPaused]` or `[onAppDetached]` logs
✅ Hub connection stays alive
✅ App runs past 14-hour mark
✅ App runs 48+ hours without restart

---

## Emergency Rollback

If new version causes issues:
1. Keep old APK as backup
2. Reinstall old version via ADB
3. Report issue with last 100 lines of logs





