# CLQMS Code Style and Conventions

## Naming Conventions

| Element | Convention | Example |
|---------|-----------|---------|
| Classes | PascalCase | `PatientController`, `PatientModel` |
| Methods | camelCase | `createPatient()`, `getPatients()` |
| Properties | snake_case (legacy) / camelCase (new) | `$patient_id` / `$patientId` |
| Constants | UPPER_SNAKE_CASE | `MAX_RETRY_COUNT` |
| Database Tables | snake_case | `patient`, `patient_visits`, `order_tests` |
| Database Columns | PascalCase (legacy) | `PatientID`, `NameFirst`, `Birthdate`, `CreatedAt` |
| JSON Fields | PascalCase | `"PatientID": "123"` |

## File and Directory Structure

### Controllers
- Grouped by domain in subdirectories: `app/Controllers/Patient/`, `app/Controllers/Specimen/`
- Each controller handles CRUD for its entity
- Use `ResponseTrait` for standardized responses

### Models
- Grouped by domain: `app/Models/Patient/`, `app/Models/Specimen/`
- Extend `BaseModel` for automatic UTC date handling
- Define `$table`, `$primaryKey`, `$allowedFields`
- Use `checkDbError()` for database error detection

## Code Patterns

### Controller Structure
```php
<?php
namespace App\Controllers\Patient;

use App\Traits\ResponseTrait;
use CodeIgniter\Controller;
use App\Models\Patient\PatientModel;

class PatientController extends Controller {
    use ResponseTrait;

    protected $db;
    protected $model;
    protected $rules;

    public function __construct() {
        $this->db = \Config\Database::connect();
        $this->model = new PatientModel();
        $this->rules = [ /* validation rules */ ];
    }

    public function index() { /* ... */ }
    public function create() { /* ... */ }
    public function show($id) { /* ... */ }
    public function update() { /* ... */ }
    public function delete() { /* ... */ }
}
```

### Model Structure
```php
<?php
namespace App\Models\Patient;

use App\Models\BaseModel;
use App\Services\AuditService;

class PatientModel extends BaseModel {
    protected $table = 'patient';
    protected $primaryKey = 'InternalPID';
    protected $allowedFields = ['PatientID', 'NameFirst', ...];
    
    protected $useTimestamps = true;
    protected $createdField = 'CreateDate';
    protected $useSoftDeletes = true;
    protected $deletedField = 'DelDate';

    public function getPatients($filters = []) { /* ... */ }
    public function createPatient($input) { /* ... */ }
    
    private function checkDbError($db, string $context) {
        $error = $db->error();
        if (!empty($error['code'])) {
            throw new \Exception("{$context} failed: {$error['code']} - {$error['message']}");
        }
    }
}
```

### Validation Rules
- Define in controller constructor as `$this->rules`
- Use CodeIgniter validation rules: `required`, `permit_empty`, `regex_match`, `max_length`, etc.
- For nested data, override rules dynamically based on input

### Response Format
```php
// Success
return $this->respond([
    'status' => 'success',
    'message' => 'Operation completed',
    'data' => $data
], 200);

// Error
return $this->respond([
    'status' => 'failed',
    'message' => 'Error description',
    'data' => []
], 400);
```

**Note:** Custom `ResponseTrait` automatically converts empty strings to `null`.

### Error Handling
- Use try-catch for JWT and external calls
- Log errors: `log_message('error', $message)`
- Return structured error responses with appropriate HTTP status codes

```php
try {
    $decoded = JWT::decode($token, new Key($key, 'HS256'));
} catch (\Firebase\JWT\ExpiredException $e) {
    return $this->respond(['status' => 'failed', 'message' => 'Token expired'], 401);
} catch (\Exception $e) {
    return $this->respond(['status' => 'failed', 'message' => 'Invalid token'], 401);
}
```

### Database Operations
- Use CodeIgniter Query Builder or Model methods
- Use `helper('utc')` for UTC date conversion
- Wrap multi-table operations in transactions

```php
$this->db->transStart();
// ... database operations
$this->db->transComplete();

if ($this->db->transStatus() === false) {
    return $this->respond(['status' => 'error', 'message' => 'Transaction failed'], 500);
}
```

### Audit Logging
Use `AuditService::logData()` for tracking data changes:
```php
AuditService::logData(
    'CREATE|UPDATE|DELETE',
    'table_name',
    (string) $recordId,
    'entity_name',
    null,
    $previousData,
    $newData,
    'Action description',
    ['metadata' => 'value']
);
```

## Route Patterns
```php
$routes->group('api/patient', function ($routes) {
    $routes->get('/', 'Patient\PatientController::index');
    $routes->post('/', 'Patient\PatientController::create');
    $routes->get('(:num)', 'Patient\PatientController::show/$1');
    $routes->patch('/', 'Patient\PatientController::update');
    $routes->delete('/', 'Patient\PatientController::delete');
});
```

## Testing Guidelines

```php
<?php
namespace Tests\Feature\Patients;

use CodeIgniter\Test\FeatureTestTrait;
use CodeIgniter\Test\CIUnitTestCase;
use Faker\Factory;

class PatientCreateTest extends CIUnitTestCase
{
    use FeatureTestTrait;

    protected $endpoint = 'api/patient';

    public function testCreatePatientSuccess()
    {
        $faker = Factory::create('id_ID');
        $payload = [...];
        $result = $this->withBodyFormat('json')->post($this->endpoint, $payload);
        $result->assertStatus(201);
    }
}
```

**Test Naming:** `test<Action><Scenario><ExpectedResult>` (e.g., `testCreatePatientValidationFail`)

## Security Best Practices
- Use `auth` filter for protected routes
- Sanitize user inputs with validation rules
- Use parameterized queries (CodeIgniter Query Builder handles this)
- Store secrets in `.env`, never commit to repository

## Legacy Field Naming
Database uses PascalCase columns: `PatientID`, `NameFirst`, `Birthdate`, `CreatedAt`, `UpdatedAt`

## ValueSet/Lookup Usage
```php
use App\Libraries\Lookups;

// Get all lookups
$allLookups = Lookups::getAll();

// Get single lookup formatted for dropdowns
$gender = Lookups::get('gender');

// Get label for a specific key
$label = Lookups::getLabel('gender', '1'); // Returns 'Female'

// Transform database records with lookup text labels
$labeled = Lookups::transformLabels($data, ['Sex' => 'gender']);
```