/// Compile-time constants and defaults.
///
/// Anything here that the user can override at runtime appears as a default
/// value in `Settings` or `LayoutController`. Anything that's truly fixed
/// (channel count, status count, severity list) lives only here.
class AppConfig {
  AppConfig._();

  /// Total channels supported by the proto schema. Don't change without
  /// updating messages.proto in lockstep.
  static const int channelCount = 16;

  /// Total status indicators supported by the proto schema.
  static const int statusCount = 8;

  /// Default per-channel display names.
  static const List<String> defaultChannelNames = [
    'CH1', 'CH2', 'CH3', 'CH4',
    'CH5', 'CH6', 'CH7', 'CH8',
    'CH9', 'CH10', 'CH11', 'CH12',
    'CH13', 'CH14', 'CH15', 'CH16',
  ];

  /// Default per-status-field display names.
  static const List<String> defaultStatusNames = [
    'status1', 'status2', 'status3', 'status4',
    'status5', 'status6', 'status7', 'status8',
  ];

  /// Default Y range when a channel is fixed-mode and the user hasn't set one.
  static const double defaultYMin = 0.0;
  static const double defaultYMax = 1.0;

  /// Default grid shape on first launch.
  static const int defaultGridRows = 2;
  static const int defaultGridCols = 2;

  /// Default packet buffer capacity (≈ 10 minutes at 1 kHz on native).
  static const int defaultPacketBufferCapacityNative = 600000;

  /// Reduced default for Web (browser heap pressure).
  static const int defaultPacketBufferCapacityWeb = 120000;

  /// Default log buffer capacity.
  static const int defaultLogBufferCapacity = 5000;

  /// Default WebSocket URL on first launch.
  static const String defaultWsUrl = 'ws://localhost:9000';

  /// Default lookback for the per-frame status snapshot.
  static const int defaultStatusLookback = 1000;

  /// Default decoder batch interval (native only).
  static const Duration defaultDecoderBatchInterval =
      Duration(milliseconds: 8);

  /// Default reconnect parameters.
  static const Duration defaultReconnectInitialDelay =
      Duration(milliseconds: 500);
  static const Duration defaultReconnectMaxDelay = Duration(seconds: 30);
  static const double defaultReconnectBackoffFactor = 2.0;

  /// Default mini-log severity filter (Dashboard tab). ERROR + FATAL.
  static const Set<int> defaultMiniLogSeverities = {4, 5};

  /// Default chart x-window on launch and after Reset View.
  static const Duration defaultWindowWidth = Duration(seconds: 10);

  /// Hard floor on the x-window — below this, charts become a handful of
  /// samples and the UI gets confusing.
  static const Duration minWindowWidth = Duration(milliseconds: 10);
}