castle/docs/PHASE2_COMPLETE.md

# Phase 2: Reconciliation - COMPLETE ✅

## Summary

Phase 2 of the Beancount-inspired refactor focused on **reconciliation and automated balance checking**. This phase builds on Phase 1's foundation to provide robust reconciliation tools that ensure accounting accuracy and catch discrepancies early.

## Completed Features

### 1. Balance Assertions ✅

**Purpose**: Verify account balances match expected values at specific points in time (like Beancount's `balance` directive)

**Implementation**:
- **Models** (`models.py:184-219`):
  - `AssertionStatus` enum (pending, passed, failed)
  - `BalanceAssertion` model with sats and optional fiat checks
  - `CreateBalanceAssertion` request model

- **Database** (`migrations.py:275-320`):
  - `balance_assertions` table with expected/actual balance tracking
  - Tolerance levels for flexible matching
  - Status tracking and timestamps
  - Indexes for performance

- **CRUD** (`crud.py:773-981`):
  - `create_balance_assertion()` - Create and store assertion
  - `get_balance_assertion()` - Fetch single assertion
  - `get_balance_assertions()` - List with filters
  - `check_balance_assertion()` - Compare expected vs actual
  - `delete_balance_assertion()` - Remove assertion

- **API Endpoints** (`views_api.py:1067-1230`):
  - `POST /api/v1/assertions` - Create and check assertion
  - `GET /api/v1/assertions` - List assertions with filters
  - `GET /api/v1/assertions/{id}` - Get specific assertion
  - `POST /api/v1/assertions/{id}/check` - Re-check assertion
  - `DELETE /api/v1/assertions/{id}` - Delete assertion

- **UI** (`templates/castle/index.html:254-378`):
  - Balance Assertions card (super user only)
  - Failed assertions prominently displayed with red banner
  - Passed assertions in collapsible panel
  - Create assertion dialog with validation
  - Re-check and delete buttons

- **Frontend** (`static/js/index.js:70-79, 602-726`):
  - Data properties and computed values
  - CRUD methods for assertions
  - Automatic loading on page load

### 2. Reconciliation API Endpoints ✅

**Purpose**: Provide comprehensive reconciliation tools and reporting

**Implementation**:
- **Summary Endpoint** (`views_api.py:1236-1287`):
  - `GET /api/v1/reconciliation/summary`
  - Returns counts of assertions by status
  - Returns counts of journal entries by flag
  - Total accounts count
  - Last checked timestamp

- **Check All Endpoint** (`views_api.py:1290-1325`):
  - `POST /api/v1/reconciliation/check-all`
  - Re-checks all balance assertions
  - Returns summary of results (passed/failed/errors)
  - Useful for manual reconciliation runs

- **Discrepancies Endpoint** (`views_api.py:1328-1357`):
  - `GET /api/v1/reconciliation/discrepancies`
  - Returns all failed assertions
  - Returns all flagged journal entries
  - Returns all pending entries
  - Total discrepancy count

### 3. Reconciliation UI Dashboard ✅

**Purpose**: Visual dashboard for reconciliation status and quick access to reconciliation tools

**Implementation** (`templates/castle/index.html:380-499`):
- **Summary Cards**:
  - Balance Assertions stats (total, passed, failed, pending)
  - Journal Entries stats (total, cleared, pending, flagged)
  - Total Accounts count with last checked timestamp

- **Discrepancies Alert**:
  - Warning banner when discrepancies found
  - Shows count of failed assertions and flagged entries
  - "View Details" button to expand discrepancy list

- **Discrepancy Details**:
  - Failed assertions list with expected vs actual balances
  - Flagged entries list
  - Quick access to problematic transactions

- **Actions**:
  - "Check All" button to run full reconciliation
  - Loading states during checks
  - Success message when all accounts reconciled

**Frontend** (`static/js/index.js:80-85, 727-779, 933-934`):
- Reconciliation data properties
- Methods to load summary and discrepancies
- `runFullReconciliation()` method with notifications
- Automatic loading on page load for super users

### 4. Automated Daily Balance Checks ✅

**Purpose**: Run balance checks automatically on a schedule to catch discrepancies early

**Implementation**:

- **Tasks Module** (`tasks.py`):
  - `check_all_balance_assertions()` - Core checking logic
  - `scheduled_daily_reconciliation()` - Scheduled wrapper
  - Results logging and reporting
  - Error handling

- **API Endpoint** (`views_api.py:1363-1390`):
  - `POST /api/v1/tasks/daily-reconciliation`
  - Can be triggered manually or via cron
  - Returns detailed results
  - Super user only

- **Documentation** (`DAILY_RECONCILIATION.md`):
  - Comprehensive setup guide
  - Multiple scheduling options (cron, systemd, k8s)
  - Monitoring and troubleshooting
  - Best practices
  - Example scripts

## Benefits

### Accounting Accuracy
- ✅ Catch data entry errors early
- ✅ Verify balances at critical checkpoints
- ✅ Build confidence in accounting accuracy
- ✅ Required for external audits

### Operational Excellence
- ✅ Automated daily checks reduce manual work
- ✅ Dashboard provides at-a-glance reconciliation status
- ✅ Discrepancies are immediately visible
- ✅ Historical tracking of assertions

### Developer Experience
- ✅ Clean API for programmatic reconciliation
- ✅ Well-documented scheduling options
- ✅ Flexible tolerance levels
- ✅ Comprehensive error reporting

## File Changes

### New Files Created
1. `tasks.py` - Background tasks for automated reconciliation
2. `DAILY_RECONCILIATION.md` - Setup and scheduling documentation
3. `PHASE2_COMPLETE.md` - This file

### Modified Files
1. `models.py` - Added `BalanceAssertion`, `CreateBalanceAssertion`, `AssertionStatus`
2. `migrations.py` - Added `m007_balance_assertions` migration
3. `crud.py` - Added balance assertion CRUD operations
4. `views_api.py` - Added assertion, reconciliation, and task endpoints
5. `templates/castle/index.html` - Added assertions and reconciliation UI
6. `static/js/index.js` - Added assertion and reconciliation functionality
7. `BEANCOUNT_PATTERNS.md` - Updated roadmap to mark Phase 2 complete

## API Endpoints Summary

### Balance Assertions
- `POST /api/v1/assertions` - Create assertion
- `GET /api/v1/assertions` - List assertions
- `GET /api/v1/assertions/{id}` - Get assertion
- `POST /api/v1/assertions/{id}/check` - Re-check assertion
- `DELETE /api/v1/assertions/{id}` - Delete assertion

### Reconciliation
- `GET /api/v1/reconciliation/summary` - Get reconciliation summary
- `POST /api/v1/reconciliation/check-all` - Check all assertions
- `GET /api/v1/reconciliation/discrepancies` - Get discrepancies

### Automated Tasks
- `POST /api/v1/tasks/daily-reconciliation` - Run daily reconciliation check

## Usage Examples

### Create a Balance Assertion
```bash
curl -X POST http://localhost:5000/castle/api/v1/assertions \
  -H "X-Api-Key: ADMIN_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "account_id": "lightning",
    "expected_balance_sats": 268548,
    "tolerance_sats": 100
  }'
```

### Get Reconciliation Summary
```bash
curl http://localhost:5000/castle/api/v1/reconciliation/summary \
  -H "X-Api-Key: ADMIN_KEY"
```

### Run Full Reconciliation
```bash
curl -X POST http://localhost:5000/castle/api/v1/reconciliation/check-all \
  -H "X-Api-Key: ADMIN_KEY"
```

### Schedule Daily Reconciliation (Cron)
```bash
# Add to crontab
0 2 * * * curl -X POST http://localhost:5000/castle/api/v1/tasks/daily-reconciliation -H "X-Api-Key: ADMIN_KEY"
```

## Testing Checklist

- [x] Create balance assertion (UI)
- [x] Create balance assertion (API)
- [x] Assertion passes when balance matches
- [x] Assertion fails when balance doesn't match
- [x] Tolerance levels work correctly
- [x] Fiat balance assertions work
- [x] Re-check assertion updates status
- [x] Delete assertion removes it
- [x] Reconciliation summary shows correct stats
- [x] Check all assertions endpoint works
- [x] Discrepancies endpoint returns correct data
- [x] Dashboard displays summary correctly
- [x] Discrepancy alert shows when issues exist
- [x] "Check All" button triggers reconciliation
- [x] Daily reconciliation task executes successfully
- [x] Failed assertions are logged
- [x] All endpoints require super user access

## Next Steps

**Phase 3: Core Logic Refactoring (Medium Priority)**
- Create `core/` module with pure accounting logic
- Implement `CastleInventory` for position tracking
- Move balance calculation to `core/balance.py`
- Add comprehensive validation in `core/validation.py`

**Phase 4: Validation Plugins (Medium Priority)**
- Create plugin system architecture
- Implement `check_balanced` plugin
- Implement `check_receivables` plugin
- Add plugin configuration UI

**Phase 5: Advanced Features (Low Priority)**
- Add tags and links to entries
- Implement query language
- Add lot tracking to inventory
- Support multi-currency in single entry

## Conclusion

Phase 2 successfully implements Beancount's reconciliation philosophy in the Castle extension. With balance assertions, comprehensive reconciliation APIs, a visual dashboard, and automated daily checks, users can:

- **Trust their data** with automated verification
- **Catch errors early** through regular reconciliation
- **Save time** with automated daily checks
- **Gain confidence** in their accounting accuracy

The implementation follows Beancount's best practices while adapting to LNbits' architecture and use case. All reconciliation features are admin-only, ensuring proper access control for sensitive accounting operations.

**Phase 2 Status**: ✅ COMPLETE

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*Generated: 2025-10-23*
*Next: Phase 3 - Core Logic Refactoring*