enum _ChainPainterOption { Top, Bottom }

class _ChainPainter extends CustomPainter {
  static const _lineWidth = 5.0;
  static const _circleRadius = 7.5;
  final Paint _linePaint = Paint()
    ..color = FMColors.c5DACE9
    ..style = PaintingStyle.stroke
    ..strokeWidth = _lineWidth;
  final Paint _circlePaint = Paint()
    ..color = FMColors.c3D80F6
    ..style = PaintingStyle.fill
    ..strokeWidth = 0.0;

  final Set<_ChainPainterOption> options;

  _ChainPainter(this.options);

  @override
  void paint(Canvas canvas, Size size) {
    final lineDx = size.width / 2;
    if (options.contains(_ChainPainterOption.Top)) {
      canvas.drawLine(Offset(lineDx, 0), Offset(lineDx, 33), _linePaint);
    }
    if (options.contains(_ChainPainterOption.Bottom)) {
      canvas.drawLine(
        Offset(lineDx, 33),
        Offset(lineDx, size.height),
        _linePaint,
      );
    }
    final circleDx = size.width / 2;
    canvas.drawCircle(Offset(circleDx, 33), _circleRadius, _circlePaint);
  }

  @override
  bool shouldRepaint(CustomPainter oldDelegate) => false;
}