false, 'error' => 'user_id is required']); exit; } $db = Database::getInstance(); // Marcar como no leídos todos los mensajes entrantes del usuario $db->execute("UPDATE conversations SET is_read = 0 WHERE user_id = ? AND direction = 'incoming'", [$userId]); echo json_encode(['success' => true]); } catch (Exception $e) { error_log('mark_conversation_unread failed: ' . $e->getMessage()); http_response_code(500); echo json_encode(['success' => false, 'error' => 'Internal server error']); } ?>