rgb2hsl method Null safety

Implementation

static List<int> rgb2hsl(List<num> rgb) {
  final num r = rgb[0] / 255.0;
  final num g = rgb[1] / 255.0;
  final num b = rgb[2] / 255.0;
  final num minC = min(r, min(g, b));
  final num maxC = max(r, max(g, b));
  final num delta = maxC - minC;
  num h = 0;
  num s;

  if (maxC == minC) {
    h = 0;
  } else if (r == maxC) {
    h = (g - b) / delta;
  } else if (g == maxC) {
    h = 2 + (b - r) / delta;
  } else if (b == maxC) {
    h = 4 + (r - g) / delta;
  }

  h = min(h * 60, 360);

  if (h < 0) {
    h += 360;
  }

  final num l = (minC + maxC) / 2;

  if (maxC == minC) {
    s = 0;
  } else if (l <= 0.5) {
    s = delta / (maxC + minC);
  } else {
    s = delta / (2 - maxC - minC);
  }

  return [h.round(), (s * 100).round(), (l * 100).round()];
}