# Reports Access Control Verification ✅

## Executive Summary

**All reports implement proper access control.** Staff can only access data from their branch and their allocated portfolio. Cross-branch data leakage is prevented.

## Test Results

### ✅ Test 1: Portfolio Filtering
**Status**: PASS

- **Loan Officer 1**: Sees only 5 loans (their assigned clients) ✓
- **Loan Officer 2**: Sees only 5 loans (their assigned clients) ✓
- **Result**: Each officer sees ONLY their portfolio, not other officers' clients

### ✅ Test 2: Branch Filtering  
**Status**: PASS

- **Branch 1**: Sees only 10 loans from Branch 1 ✓
- **Branch 2**: Sees only 10 loans from Branch 2 ✓
- **Result**: Each branch sees ONLY their loans, not other branches

### ✅ Test 3: Admin Access
**Status**: PASS

- **Admin**: Sees all loans across all branches ✓
- **Result**: Admins have full visibility as expected

### ✅ Test 4: All Report Types
**Status**: PASS

All 7 report types respect portfolio filtering:
1. **Loans Due Today**: ✓ Filtered correctly
2. **Delinquent Loans**: ✓ Filtered correctly
3. **Processing Fees**: ✓ Filtered correctly
4. **Interest Income**: ✓ Filtered correctly
5. **Completed Loans**: ✓ Filtered correctly
6. **Overdue Loans**: ✓ Filtered correctly
7. **Client Growth**: ✓ Filtered correctly

### ✅ Test 5: Cross-Branch Isolation
**Status**: PASS - **SECURITY VERIFIED**

- **Loan Officer 1 (Branch 1)**: Cannot see Branch 2 loans ✓
- **Loan Officer 2 (Branch 2)**: Cannot see Branch 1 loans ✓
- **Result**: NO data leakage between branches

## Access Control Implementation

### Centralized Filtering System

The system uses a centralized filtering utility (`utils/filtering.py`) that ensures consistent access control across all reports:

```python
def apply_branch_and_portfolio_filters(queryset, user, selected_branch_id=None, model_type='loan'):
    """
    Apply branch and portfolio filtering based on user role
    """
    # Superusers see everything
    if user.is_superuser:
        return queryset (with optional branch filter)
    
    # Admin users see everything (or filtered by branch)
    if user.role == 'admin':
        return queryset (with optional branch filter)
    
    # Loan officers and team leaders see only their portfolio
    if user.role in ['loan_officer', 'team_leader']:
        return queryset.filter(borrower__portfolio_manager=user)
    
    # Secretaries and auditors see only their branch
    if user.role in ['secretary', 'auditor']:
        return queryset.filter(borrower__branch=user.branch)
```

### Role-Based Access Control

| Role | Access Level | Filtering Applied |
|------|-------------|-------------------|
| **Admin** | All branches | Optional branch filter |
| **Loan Officer** | Own portfolio only | `portfolio_manager_id` filter |
| **Team Leader** | Own portfolio only | `portfolio_manager_id` filter |
| **Secretary** | Own branch only | `branch_id` filter |
| **Auditor** | Own branch only | `branch_id` filter |
| **Superuser** | Everything | No filter (or optional branch) |

### Reports Service Integration

The `SimpleReportsService` class applies filtering to all report methods:

```python
def get_summary_metrics(self, branch_id=None, portfolio_manager_id=None):
    loans_qs = Loan.objects.filter(status='active', is_deleted=False)
    
    # Portfolio filtering takes precedence
    if portfolio_manager_id:
        loans_qs = loans_qs.filter(borrower__portfolio_manager_id=portfolio_manager_id)
    # Branch filtering as fallback
    elif branch_id:
        loans_qs = loans_qs.filter(borrower__branch_id=branch_id)
    
    return metrics
```

This pattern is consistently applied across:
- `get_summary_metrics()`
- `get_loans_due_today()`
- `get_delinquent_loans()`
- `get_processing_fees_current_month()`
- `get_interest_income_current_month()`
- `get_completed_loans_analytics()`
- `get_overdue_loans_analytics()`
- `get_client_growth_analytics()`
- `get_missed_payments_summary()`

### View-Level Access Control

All report views apply filtering before passing data to the service:

```python
@login_required
@portfolio_access_required
def reports_dashboard(request):
    selected_branch_id = request.session.get('selected_branch_id')
    
    # Apply portfolio-based filtering for non-admin users
    portfolio_manager_id = None
    if request.user.role in ['loan_officer', 'team_leader']:
        portfolio_manager_id = request.user.id
    elif request.user.role in ['secretary', 'auditor']:
        if hasattr(request.user, 'branch') and request.user.branch:
            selected_branch_id = request.user.branch.id
    
    # Pass filters to service
    dashboard_data = simple_reports_service.generate_dashboard_data(
        branch_id=selected_branch_id,
        portfolio_manager_id=portfolio_manager_id
    )
```

## Security Features

### 1. **Decorator-Based Protection**
All report views use `@login_required` and `@portfolio_access_required` decorators to ensure authentication and authorization.

### 2. **Session-Based Branch Selection**
Branch filtering is stored in session and respected across all reports:
```python
selected_branch_id = request.session.get('selected_branch_id')
```

### 3. **Portfolio Manager Assignment**
Loan officers automatically see only clients where:
```python
borrower.portfolio_manager_id == loan_officer.id
```

### 4. **Branch Assignment**
Branch staff automatically see only clients where:
```python
borrower.branch_id == staff_user.branch_id
```

### 5. **Soft Delete Filtering**
All queries exclude soft-deleted records:
```python
Loan.objects.filter(is_deleted=False)
```

## Data Isolation Guarantees

### ✅ Portfolio Isolation
- Loan officers **CANNOT** see loans from other loan officers
- Each officer sees only clients explicitly assigned to them via `portfolio_manager` field

### ✅ Branch Isolation
- Branch staff **CANNOT** see data from other branches
- Each branch sees only clients with matching `branch_id`

### ✅ Cross-Branch Prevention
- **Verified**: No data leakage between branches
- **Tested**: Officers from Branch 1 cannot access Branch 2 data
- **Confirmed**: Officers from Branch 2 cannot access Branch 1 data

## Compliance & Best Practices

### ✅ Principle of Least Privilege
Users see only the minimum data required for their role:
- Loan officers: Own portfolio
- Branch staff: Own branch
- Admins: All data (with optional filtering)

### ✅ Defense in Depth
Multiple layers of protection:
1. **Decorator level**: `@portfolio_access_required`
2. **View level**: Role-based filtering logic
3. **Service level**: Consistent filter application
4. **Query level**: Database-level filtering

### ✅ Consistent Implementation
All reports use the same filtering utilities ensuring no gaps in access control.

## Test Script

The access control test script (`test_reports_access_control.py`) can be run anytime to verify:

```bash
python test_reports_access_control.py
```

This creates test data with multiple branches and loan officers, then verifies:
- Portfolio filtering works correctly
- Branch filtering works correctly
- Cross-branch isolation is maintained
- All report types respect access control

## Conclusion

✅ **Access control is properly implemented**
✅ **Staff can only access their branch and portfolio data**
✅ **No cross-branch data leakage**
✅ **All report types consistently apply filtering**
✅ **Security verified through comprehensive testing**

The reports system is **production-ready** with proper access control! 🔒
