pi-pm3/IMPLEMENTATION_PRIORITIES.md

Implementation Priorities - Updated

Date: 2025-11-26 Status: Active Development

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🔴 PRIORITY 1: Power Management (BEFORE PI TESTING)

Why Critical: System behavior must be defined for UPS-present and UPS-absent scenarios before deploying to hardware.

Tasks

1.1 UPS Manager - Power Restrictions Method ⚠️ CRITICAL

• File: app/backend/managers/ups_manager.py
• Action: Add get_power_restrictions() method
• Estimated Time: 30 minutes
• Blocks: All hardware testing

Implementation:

def get_power_restrictions(self) -> Dict[str, Any]:
    """Get current power restrictions based on hardware state."""
    # See POWER_MANAGEMENT_POLICY.md for full implementation

1.2 System API - Power Restrictions Endpoint

• File: app/backend/api/system.py
• Action: Add GET /api/system/power/restrictions endpoint
• Estimated Time: 15 minutes
• Depends on: 1.1

Implementation:

@router.get("/power/restrictions")
async def get_power_restrictions():
    """Get current power restrictions."""
    # See POWER_MANAGEMENT_POLICY.md

1.3 Header Widget - UPS Missing Warning

• File: Multiple (plugin_manager, ups_manager)
• Action: Register widget when UPS not detected
• Estimated Time: 20 minutes
• Depends on: Header widget system (can defer to Phase 2)

1.4 Documentation Update

• Files:
  • README.md - Add power management section
  • GETTING_STARTED.md - Mention UPS optional
  • PROJECT_STATUS.md - Update status
• Estimated Time: 15 minutes

Total Time: ~1.5 hours for Phase 1 (core functionality)

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🟡 PRIORITY 2: Header Widget System (OPTIONAL FOR TESTING)

Why Important: Good UX, but not required for basic Pi testing

Tasks

2.1 Backend Widget Infrastructure

• Add HeaderWidget dataclass to plugin_manager
• Add widget registry methods
• Add dismissed widgets tracking
• Estimated Time: 1 hour

2.2 API Endpoints

• GET /api/system/widgets
• POST /api/system/widgets/{id}/dismiss
• Estimated Time: 30 minutes

2.3 Frontend Component

• Create HeaderWidgets.tsx
• Add CSS styles
• Integrate into root.tsx
• Estimated Time: 1.5 hours

2.4 UPS Integration

• Register widget on missing hardware
• Register widget on low battery
• Estimated Time: 30 minutes

Total Time: ~3.5 hours

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🟢 PRIORITY 3: Pi-gen Build Testing (READY TO GO)

Status: Scripts complete, ready for build

Tasks

3.1 Test Build

• Run ./build-image.sh quick
• Verify PM3 client builds
• Verify Python bindings work
• Estimated Time: 30 minutes (build time 5-10 min)

3.2 Fix Issues

• Address any build failures
• Update scripts as needed
• Estimated Time: Variable

3.3 Full Build

• Run ./build-image.sh full
• Create complete bootable image
• Estimated Time: 1-2 hours (build time)

Total Time: 2-3 hours

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🔵 PRIORITY 4: Hardware Testing

Prerequisites: Priorities 1 & 3 complete

4.1 Deploy to Pi Zero 2 W

• Flash SD card with custom image
• Boot and verify services start
• Test web interface access

4.2 Test Without UPS

• Verify power restrictions return "assumed AC"
• Verify header widget shows warning
• Verify no unexpected restrictions

4.3 Test With UPS (if available)

• Connect UPS HAT
• Verify battery monitoring works
• Test power restrictions on battery
• Test AC power detection

4.4 Test PM3 Operations

• Connect PM3 device
• Execute commands
• Test multi-device (if available)

Total Time: 2-4 hours

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🟣 PRIORITY 5: Future Enhancements (POST-MVP)

• Firmware flashing UI (Sprint 3)
• Advanced header widgets
• Plugin ecosystem
• Multi-device hardware testing

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Recommended Order

Session Today: Power Management

1. ✅ Plans A, B, C (cloud-init, PYTHONPATH, port conflict) - DONE
2. ✅ Header widget system design - DONE
3. ✅ Power management policy design - DONE
4. ⏭️ NEXT: Implement Priority 1 (Power Management)

Next Session: Build & Deploy

1. Test pi-gen build (Priority 3)
2. Deploy to Pi hardware (Priority 4)
3. Verify power management works
4. Test PM3 operations

Future Session: Polish

1. Implement header widgets (Priority 2)
2. Add firmware flashing (Sprint 3)
3. Advanced features

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Quick Implementation Guide

Step 1: Add Power Restrictions to UPS Manager

# Edit UPS manager
nano app/backend/managers/ups_manager.py

# Add get_power_restrictions() method
# See POWER_MANAGEMENT_POLICY.md lines 49-120

Step 2: Add API Endpoint

# Edit system API
nano app/backend/api/system.py

# Add /power/restrictions endpoint
# See POWER_MANAGEMENT_POLICY.md lines 166-180

Step 3: Test Locally

# Start backend
cd app/backend
python -m uvicorn main:app --reload

# Test endpoint
curl http://localhost:8000/api/system/power/restrictions

Step 4: Update Docs

# Update PROJECT_STATUS.md
# Update README.md with power management info

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Success Criteria

Priority 1 Complete When:

• Power management policy documented
• get_power_restrictions() method implemented
• API endpoint /api/system/power/restrictions working
• Returns correct response when UPS not detected
• Returns correct response when UPS on AC
• Returns correct response when UPS on battery
• Documentation updated

Ready for Pi Testing When:

• Priority 1 complete
• Priority 3 complete (build tested)
• Services start correctly
• Web interface accessible
• No Python import errors

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Current Status: Priority 1 design complete, implementation needed (~1.5 hours) Blocker: Must implement before Pi deployment Next Action: Implement get_power_restrictions() method