calculateBMR method

@override Future<double> calculateBMR({ required double weight, required double height, required int age, required bool isMale, required double bodyFatPercentage, Ethnicity ethnicity = Ethnicity.white, })

Implementation

@override
Future<double> calculateBMR({
  required double weight,
  required double height,
  required int age,
  required bool isMale,
  required double bodyFatPercentage,
  Ethnicity ethnicity = Ethnicity.white,
}) async {
  // Validate inputs
  if (weight <= 0 ||
      height <= 0 ||
      age <= 0 ||
      bodyFatPercentage < 0 ||
      bodyFatPercentage > 100) {
    throw ArgumentError("Invalid input values.");
  }

  double bmi =
      BodyMassIndex.calculateKiloAndMeters(weight: weight, height: height);
  double fatFreeMass = weight * (1 - bodyFatPercentage / 100);

  if (age >= 60) {
    return _calculateCunningham(fatFreeMass);
  }

  double bmr = _calculateMifflinStJeor(weight, height, age, isMale);

  switch (ethnicity) {
    case Ethnicity.black:
      bmr = _calculateOwen(weight, isMale);
      break;
    case Ethnicity.asian:
      bmr = _calculateHenry(weight, height, age, isMale);
      break;
    case Ethnicity.hispanic:
      bmr *= 1.05; // Simple adjustment factor
      break;
    case Ethnicity.white:
    case Ethnicity.other:
    default:
      break;
  }

  if (bmi < 18.5) {
    bmr = _calculateOwen(weight, isMale);
  } else if (bmi >= 30) {
    bmr = _calculateMuller(weight, height, age, isMale);
  }

  return Future.value(bmr);
}