enum CalibrationPhase { idle, selectingTag, ready, collecting, done, error }

const calibrationDistances = [0.5, 1.0, 2.0, 3.0];

class CalibrationState {
  const CalibrationState({
    this.phase = CalibrationPhase.idle,
    this.samplesNeeded = 0,
    this.samplesCollected = 0,
    this.selectedDistance,
    this.completedDistances = const {},
    this.waveform = const [],
    this.latestRssi,
    this.avgRssi,
    this.resultRssiRef,
    this.resultPathLossExp,
    this.tagRssiReadings = const {},
    this.selectedTagId,
    this.error,
  });

  final CalibrationPhase phase;
  final int samplesNeeded;
  final int samplesCollected;
  final double? selectedDistance;
  final Set<double> completedDistances;
  /// Circular buffer of recent RSSI readings for the waveform, max 30.
  final List<double> waveform;
  final double? latestRssi;
  final double? avgRssi;
  final double? resultRssiRef;
  final double? resultPathLossExp;
  /// Latest scan RSSI per tag device ID, updated during selectingTag phase.
  final Map<String, double> tagRssiReadings;
  /// The tag device ID committed for this calibration session.
  final String? selectedTagId;
  final String? error;

  bool get canFinish =>
      completedDistances.length >= 2 && phase != CalibrationPhase.collecting;

  double get progress =>
      samplesNeeded == 0 ? 0 : samplesCollected / samplesNeeded;

  CalibrationState copyWith({
    CalibrationPhase? phase,
    int? samplesNeeded,
    int? samplesCollected,
    double? selectedDistance,
    Set<double>? completedDistances,
    List<double>? waveform,
    double? latestRssi,
    double? avgRssi,
    double? resultRssiRef,
    double? resultPathLossExp,
    Map<String, double>? tagRssiReadings,
    String? selectedTagId,
    String? error,
    bool clearSelectedDistance = false,
    bool clearLatestRssi = false,
    bool clearAvgRssi = false,
    bool clearTagRssiReadings = false,
    bool clearSelectedTagId = false,
    bool clearError = false,
  }) =>
      CalibrationState(
        phase: phase ?? this.phase,
        samplesNeeded: samplesNeeded ?? this.samplesNeeded,
        samplesCollected: samplesCollected ?? this.samplesCollected,
        selectedDistance: clearSelectedDistance
            ? null
            : selectedDistance ?? this.selectedDistance,
        completedDistances: completedDistances ?? this.completedDistances,
        waveform: waveform ?? this.waveform,
        latestRssi: clearLatestRssi ? null : latestRssi ?? this.latestRssi,
        avgRssi: clearAvgRssi ? null : avgRssi ?? this.avgRssi,
        resultRssiRef: resultRssiRef ?? this.resultRssiRef,
        resultPathLossExp: resultPathLossExp ?? this.resultPathLossExp,
        tagRssiReadings: clearTagRssiReadings
            ? const {}
            : tagRssiReadings ?? this.tagRssiReadings,
        selectedTagId:
            clearSelectedTagId ? null : selectedTagId ?? this.selectedTagId,
        error: clearError ? null : error ?? this.error,
      );
}