Lg Debugger

Common Fixes:

// WRONG: Missing timeout
await SSHSocket.connect(host, port);

// RIGHT: Always set a connection timeout
await SSHSocket.connect(host, port, timeout: const Duration(seconds: 10));

2. KML Not Showing on Google Earth

Symptoms: KML sent but nothing appears on the rig screens.

Diagnostic Steps:

1. Validate KML: Open in Google Earth Pro (desktop) first.
2. Coordinate order: KML uses longitude,latitude — most bugs are swapped lat/lon.
3. File path: Verify writing to /var/www/html/kml/slave_0.kml (check slave number).
4. Clear first: Old KML might override new. Call clearKML() before sendKML().
5. SSH command: Verify the echo '...' > /path command executes without error.
6. Google Earth refresh: GE may need a NetworkLink refresh or manual reload.

Common Fixes:

// WRONG: Lat/Lon swapped
'<coordinates>$latitude,$longitude,0</coordinates>'

// RIGHT: KML is lon,lat,alt
'<coordinates>$longitude,$latitude,0</coordinates>'

3. Provider / State Management Issues

Symptoms: UI doesn't update, "ProviderNotFoundException", stale data.

Diagnostic Steps:

1. Provider registered? Check MultiProvider in main.dart.
2. Watch vs Read: Use context.watch<T>() for reactive rebuilds, context.read<T>() for one-time.
3. notifyListeners(): Called after every state mutation?
4. Disposed?: Service not accessed after dispose() called?
5. Scope: Provider placed above the widget that needs it in the tree?

4. Async/Network Issues

Symptoms: App freezes, unhandled exceptions, loading states stuck.

Diagnostic Steps:

1. Try-catch: Is the async call wrapped?
2. Timeout: API or SSH call hanging without timeout?
3. Loading state: _isLoading set to false in finally block?
4. Error propagation: Exception caught but not displayed to user?

5. Build/Compile Errors

Symptoms: flutter analyze fails, red underlines, missing imports.

Diagnostic Steps:

1. flutter pub get — dependency resolution.
2. flutter clean && flutter pub get — clear build cache.
3. Check pubspec.yaml — correct package names and versions.
4. Check imports — relative vs package imports within lib/.
5. Check null safety — all ? and ! operators used correctly.

🛠 Debug Workflow

1. Reproduce → Can you trigger the bug consistently?
2. Isolate → Which layer? (UI, Service, SSH, KML, API)
3. Trace → Follow data flow: Widget → Service → SSH → Rig
4. Fix → Apply targeted fix in the correct layer
5. Verify → flutter analyze + flutter test + manual test
6. Document → Add to docs/tech-debt.md if it was a systemic issue

📋 Quick Reference: LG-Specific Debug Commands

# Check if LG rig is reachable
ping 192.168.1.100

# SSH into LG master manually
ssh [email protected]

# Check if Google Earth is running on the rig
ssh [email protected] "pgrep -f google-earth"

# Read current KML on master
ssh [email protected] "cat /var/www/html/kml/slave_0.kml"

# Read current query (camera control)
ssh [email protected] "cat /tmp/query.txt"

# Clear all KML manually
ssh [email protected] "echo '' > /var/www/html/kml/slave_0.kml"

# Relaunch Google Earth
ssh [email protected] "killall googleearth-bin; sleep 2; /opt/google/earth/pro/googleearth-bin &"

Reference Links

• Lucia's LG Master App (working reference): https://github.com/LiquidGalaxyLAB/LG-Master-Web-App
• dartssh2 docs: https://pub.dev/packages/dartssh2
• KML Reference (validate your KML): https://developers.google.com/kml/documentation/kmlreference
• Flutter debugging guide: https://docs.flutter.dev/testing/debugging
• LG rig setup/troubleshooting: https://github.com/LiquidGalaxyLAB/liquid-galaxy/wiki
• For deeper study → lg-learning-resources (.agent/skills/lg-learning-resources/SKILL.md)

⛔ Student Interaction Checkpoints

After Diagnosing — Explain Root Cause

⛔ STOP and WAIT — After identifying the bug, ask:

"I've found the root cause: [describe the issue]. Before I apply the fix — can you explain in your own words WHY this bug happens? What's the underlying principle being violated?"

Wait for the student's answer. Evaluate:

• ✅ Correct: They understand the root cause (e.g., lat/lon swap, missing notifyListeners(), no timeout).
• ⚠️ Partially correct: Guide them deeper — ask them to trace the data flow through the affected layers.
• ❌ Wrong or "just fix it": Trigger Critical Advisor (.agent/skills/lg-critical-advisor/SKILL.md). Debugging IS learning.

Before Applying Fix — Predict the Change

⛔ STOP and WAIT — Ask:

"I'm about to change [file/method]. What do you think the fix looks like? Describe the change before I show you the code."

Let the student attempt to describe the fix, then show the actual code.

After Fix — Verify Understanding

⛔ STOP and WAIT — After applying and verifying the fix, ask:

"How would you prevent this type of bug in the future? Should we add a test for this case?"

📋 Doc Save — Debug Session

For systemic issues, save to docs/tech-debt.md (already existing).

Additionally, save debug session context:

Save to: docs/aimentor/YYYY-MM-DD-debug-session.md

Include:

• Bug description and symptoms
• Root cause analysis
• Fix applied (with file paths)
• Lessons learned
• Prevention strategy (test added? pattern documented?)

Handoff

After fix → lg-code-reviewer for verification that the fix is clean.

🔗 Skill Chain

After the fix is applied, verified, and the student understands the root cause, automatically offer the next stage:

"Bug squashed and verified! You traced the root cause like a pro. Want to resume the pipeline where we left off, or run a code review on the fix? 🐛→✅"

If student wants to resume → activate .agent/skills/lg-resume-pipeline/SKILL.md. If student wants review → activate .agent/skills/lg-code-reviewer/SKILL.md.