# Capability 7: Utilization Calculations - Code Review

## Review Date: 2026-03-22
## Reviewer: Claude (Automated)

---

## Summary

This code review covers the Utilization Calculations capability implementation. Overall, the code follows TDD principles and is well-structured. Several issues were identified that have been addressed.

---

## Issues Found

### 1. Backend - UtilizationService

#### ✅ Fixed: Missing Cache Invalidation Hook

**File:** `backend/app/Services/UtilizationService.php`
**Severity:** High → **Status:** ✅ Fixed

**Fix Applied:**
- Created `backend/app/Observers/AllocationObserver.php`
- Registered observer in `backend/app/Providers/AllocationEventServiceProvider.php`
- Observer calls `forgetUtilizationCache()` on allocation create/update/delete

---

#### 🟡 Deferred: Batch Query Not Optimized

**File:** `backend/app/Services/UtilizationService.php:56-64`
**Severity:** Medium → **Status:** 🟡 Deferred (Low Priority)

The `calculateRunningUtilization` method runs individual queries in a loop for each month. This is acceptable for typical usage (3-12 months YTD).

**Recommendation:** For production with large teams, consider batching the allocation queries.

---

### 2. Backend - UtilizationController

#### ✅ Fixed: Authorization Policy

**File:** `backend/app/Http/Controllers/Api/UtilizationController.php`
**Severity:** Medium → **Status:** ✅ Fixed

**Fix Applied:**
- Added `use Illuminate\Foundation\Auth\Access\AuthorizesRequests` trait
- Created policies:
  - `viewRunningUtilization` - allows viewing running utilization
  - `viewOverallUtilization` - allows viewing overall utilization
  - `viewUtilization` - allows viewing combined utilization data
  - `viewTeamUtilization` - allows viewing team utilization
  - `viewTeamRunningUtilization` - allows viewing team running utilization
  - `viewUtilizationTrend` - allows viewing utilization trends

---

### 3. Frontend - UtilizationBadge Component

#### ✅ Fixed: Missing Accessibility

**File:** `frontend/src/lib/components/common/UtilizationBadge.svelte`
**Severity:** Medium → **Status:** ✅ Fixed

**Fix Applied:**
- Added `role="status"` for screen reader compatibility
- Added `aria-label="Utilization: {percentage}, {status}"` for accessible context

---

### 4. Frontend - Utilization Service

#### ✅ Fixed: No Error Handling

**File:** `frontend/src/lib/services/utilizationService.ts`
**Severity:** Low → **Status:** ✅ Fixed

**Fix Applied:**
- Created `UtilizationServiceError` custom error class
- Added `safeApiCall<T>()` wrapper function with try-catch
- Wrapped all API methods with error handling
- Errors now include message, code, and original error details

---

### 5. Testing

#### 🟡 Pending: E2E Tests Marked as fixme

**File:** `frontend/tests/e2e/utilization.spec.ts`
**Severity:** Medium → **Status:** 🟡 Pending

All E2E tests use `test.fixme()` - they require frontend UI to be implemented first.

---

#### ✅ Fixed: Unit Tests Coverage

**File:** `backend/tests/Unit/Services/UtilizationServiceTest.php`
**Status:** ✅ 31 tests passing

---

## Security Considerations

1. ✅ **Authorization Implemented:** Policies control access to utilization data
2. ✅ **Input Validation:** Laravel validates UUID format and date format

---

## Performance Considerations

1. **Caching:** 1-hour cache TTL is appropriate for utilization data that changes with allocations
2. **Cache Invalidation:** Properly invalidated on allocation changes

---

## Fixes Summary

| Issue | Priority | Status | Fix Applied |
|------|---------|--------|--------------|
| Cache invalidation | P1 | ✅ Fixed | AllocationObserver clears cache |
| Authorization policy | P2 | ✅ Fixed | TeamMemberPolicy with view methods |
| E2E tests | P2 | 🟡 Pending | Needs frontend UI |
| Accessibility | P3 | ✅ Fixed | Added role="status" and aria-label |
| Error handling | P3 | ✅ Fixed | Added try-catch with safeApiCall wrapper |
| Batch query | P3 | 🟡 Deferred | Low priority |

---

## Remaining Action Items

| Priority | Issue | File | Notes |
|----------|-------|------|-------|
| 🟡 P2 | E2E tests implementation | utilization.spec.ts | Needs frontend UI |

**Note:** The E2E tests require the utilization display to be integrated into the frontend UI. The tests are written and ready, just need to be unmarked from `test.fixme()` once the UI components are in place.
