/// 全局业务常量集中地。
///
/// 收口此前散落在各处的「业务魔数」：网络超时、轮询间隔、重试退避、输入防抖、
/// 分页大小、业务上限等可调参数。**不**收 UI 尺寸/间距/字号等纯样式常量
/// （那些保留在各自 widget / 主题里，离使用点最近更易维护）。
///
/// 新增需要复用或可能调整的业务数值时，统一加到这里，避免再写裸字面量。
abstract final class AppConstants {
  // ── 网络超时 ──
  /// 未登录公共 Dio（登录/刷新）连接超时
  static const Duration publicConnectTimeout = Duration(seconds: 8);

  /// 未登录公共 Dio 读取超时
  static const Duration publicReceiveTimeout = Duration(seconds: 15);

  /// 登录态探测/轻量请求超时
  static const Duration authProbeTimeout = Duration(seconds: 4);

  /// 异常上报请求超时
  static const Duration errorReportTimeout = Duration(seconds: 5);

  /// 检查更新请求超时
  static const Duration updateCheckTimeout = Duration(seconds: 5);

  /// 连通性探测请求超时
  static const Duration connectivityTimeout = Duration(seconds: 15);

  /// 批量导入（Excel 上传）发送超时
  static const Duration importSendTimeout = Duration(seconds: 120);

  /// 批量导入（Excel 解析入库）读取超时
  static const Duration importReceiveTimeout = Duration(seconds: 300);

  // ── 重试 / 退避 ──
  /// 网络层错误自动重试的递增间隔（1s → 2s → 4s）
  static const List<Duration> retryBackoffs = [
    Duration(seconds: 1),
    Duration(seconds: 2),
    Duration(seconds: 4),
  ];

  /// 连通性探测的多轮预算（4s → 8s → 12s）
  static const List<Duration> connectivityBudgets = [
    Duration(seconds: 4),
    Duration(seconds: 8),
    Duration(seconds: 12),
  ];

  /// 连通性探测单轮（不重试）预算
  static const List<Duration> connectivitySingleBudget = [Duration(seconds: 4)];

  /// 连通性探测每轮失败后的退避步长（600ms × 轮次）
  static const Duration connectivityRetryStep = Duration(milliseconds: 600);

  // ── 轮询间隔 ──
  /// 会话心跳上报间隔
  static const Duration heartbeatInterval = Duration(seconds: 30);

  /// 在线时连通性轮询间隔
  static const Duration connectivityOnlinePoll = Duration(seconds: 30);

  /// 离线时连通性轮询间隔
  static const Duration connectivityOfflinePoll = Duration(minutes: 1);

  /// 后台检查更新轮询间隔
  static const Duration updatePollInterval = Duration(hours: 1);

  /// 启动后首次检查更新前的延迟
  static const Duration updateInitialDelay = Duration(seconds: 3);

  // ── 输入防抖 / 交互延迟 ──
  /// 下拉框失焦自动收起延迟
  static const Duration dropdownCloseDelay = Duration(milliseconds: 150);

  /// 搜索输入防抖
  static const Duration searchDebounce = Duration(milliseconds: 300);

  /// 自更新流程各步骤间的过渡延迟
  static const Duration updaterStepDelay = Duration(milliseconds: 400);

  // ── 分页 ──
  /// 列表默认每页条数
  static const int defaultPageSize = 20;

  /// 入库选货弹窗一次性拉取的库存条数
  static const int stockInPickerPageSize = 500;

  /// 出库选货弹窗一次性拉取的库存条数
  static const int stockOutPickerPageSize = 1000;

  /// 盘点拉取库存的每页条数
  static const int inventoryCheckPageSize = 200;

  // ── 业务上限 ──
  /// 授权未返回时的默认设备上限
  static const int defaultMaxDevices = 3;
}