class ChartDataPoint {
  final DateTime timestamp;
  final double dropsPerMinute;

  ChartDataPoint({
    required this.timestamp,
    required this.dropsPerMinute,
  });

  /// Label waktu format HH:mm, dipakai di sumbu X grafik & tooltip.
  String get timeLabel {
    final h = timestamp.hour.toString().padLeft(2, '0');
    final m = timestamp.minute.toString().padLeft(2, '0');
    return '$h:$m';
  }

  @override
  String toString() {
    return 'ChartDataPoint(timestamp: $timestamp, dropsPerMinute: $dropsPerMinute)';
  }
}