// ============================================================================
// ADD THIS METHOD TO: app/Controllers/Specimen/SpecimenController.php
// ============================================================================

/**
 * Delete a specimen (soft delete)
 * DELETE /api/specimen/(:num)
 */
public function delete($id) {
    try {
        // Check if specimen exists
        $specimen = $this->model->where('SID', $id)->first();
        
        if (empty($specimen)) {
            return $this->respond([
                'status' => 'failed',
                'message' => 'Specimen not found',
                'data' => null
            ], 404);
        }
        
        // Perform soft delete (set DelDate)
        $deleted = $this->model->update($id, [
            'DelDate' => date('Y-m-d H:i:s')
        ]);
        
        if (!$deleted) {
            return $this->respond([
                'status' => 'failed',
                'message' => 'Failed to delete specimen',
                'data' => null
            ], 500);
        }
        
        return $this->respond([
            'status' => 'success',
            'message' => 'Specimen deleted successfully',
            'data' => ['SID' => $id]
        ], 200);
        
    } catch (\Exception $e) {
        log_message('error', 'SpecimenController::delete error: ' . $e->getMessage());
        return $this->respond([
            'status' => 'failed',
            'message' => 'Failed to delete specimen',
            'data' => null
        ], 500);
    }
}