class QuestionAuditBarSlot {
  const QuestionAuditBarSlot({
    required this.asOf,
    required this.avgPrice,
    required this.volume,
    required this.volumeUsd,
    this.open,
    this.high,
    this.low,
    this.close,
  });

  final DateTime asOf;
  final num? open;
  final num? high;
  final num? low;
  final num? close;
  final num avgPrice;
  final num volume;
  final num volumeUsd;

  factory QuestionAuditBarSlot.fromJson(Map<String, dynamic> json) {
    final num avgPrice = json['avgPrice'] as num;
    final num volume = json['volume'] as num;
    return QuestionAuditBarSlot(
      asOf: DateTime.parse(json['asOf']! as String).toUtc(),
      open: json['open'] as num?,
      high: json['high'] as num?,
      low: json['low'] as num?,
      close: json['close'] as num?,
      avgPrice: avgPrice,
      volume: volume,
      volumeUsd: json['volumeUsd'] as num? ?? volume * avgPrice,
    );
  }
}

class QuestionAuditAsset {
  const QuestionAuditAsset({
    required this.symbol,
    required this.priceDelta,
    required this.volumeDelta,
    required this.olderSlot,
    required this.newerSlot,
  });

  final String symbol;
  final num priceDelta;
  final num volumeDelta;
  final QuestionAuditBarSlot olderSlot;
  final QuestionAuditBarSlot newerSlot;

  factory QuestionAuditAsset.fromJson(Map<String, dynamic> json) {
    return QuestionAuditAsset(
      symbol: json['symbol']! as String,
      priceDelta: json['priceDelta'] as num,
      volumeDelta: json['volumeDelta'] as num,
      olderSlot: QuestionAuditBarSlot.fromJson(
        json['olderSlot']! as Map<String, dynamic>,
      ),
      newerSlot: QuestionAuditBarSlot.fromJson(
        json['newerSlot']! as Map<String, dynamic>,
      ),
    );
  }
}

/// US RTH session-half slot length (9:30–12:45 and 12:45–16:00 ET).
const Duration _sessionHalfSlotDuration = Duration(hours: 3, minutes: 15);

class QuestionAuditReport {
  const QuestionAuditReport({
    required this.compareUntil,
    required this.newerSlotStart,
    required this.olderSlotStart,
    required this.windowDays,
    required this.assets,
    required this.canStepOlder,
    required this.canStepNewer,
    this.stepOlderCompareUntil,
    this.stepNewerCompareUntil,
  });

  final DateTime compareUntil;
  final DateTime newerSlotStart;
  final DateTime olderSlotStart;
  final int windowDays;
  final List<QuestionAuditAsset> assets;
  final bool canStepOlder;
  final bool canStepNewer;
  final DateTime? stepOlderCompareUntil;
  final DateTime? stepNewerCompareUntil;

  factory QuestionAuditReport.fromJson(Map<String, dynamic> json) {
    final List<dynamic> raw = json['assets'] as List<dynamic>? ?? <dynamic>[];
    final DateTime compareUntil = DateTime.parse(
      (json['compareUntil'] ?? json['asOf'])! as String,
    ).toUtc();
    return QuestionAuditReport(
      compareUntil: compareUntil,
      newerSlotStart: json['newerSlotStart'] == null
          ? compareUntil.subtract(_sessionHalfSlotDuration)
          : DateTime.parse(json['newerSlotStart']! as String).toUtc(),
      olderSlotStart: json['olderSlotStart'] == null
          ? compareUntil.subtract(_sessionHalfSlotDuration * 2)
          : DateTime.parse(json['olderSlotStart']! as String).toUtc(),
      windowDays: (json['windowDays'] as num).toInt(),
      canStepOlder: json['canStepOlder'] as bool? ?? false,
      canStepNewer: json['canStepNewer'] as bool? ?? false,
      stepOlderCompareUntil: _parseOptionalUtc(json['stepOlderCompareUntil']),
      stepNewerCompareUntil: _parseOptionalUtc(json['stepNewerCompareUntil']),
      assets: raw
          .map(
            (dynamic item) =>
                QuestionAuditAsset.fromJson(item as Map<String, dynamic>),
          )
          .toList(growable: false),
    );
  }
}

DateTime? _parseOptionalUtc(dynamic raw) {
  if (raw == null) {
    return null;
  }
  return DateTime.parse(raw as String).toUtc();
}