fade light

int greenLed = 11;
int redLed = 10;
int blueLed = 9;
int yellowLed = 6;




class FADE {
private:
  int fadeAmount = 0;

  enum ledState {
  fullOff,
  fullOn
};

  enum ledState currentState = fullOff;

public:
  void fadeLed(int ledPin, int fadeSpeed, int fadeRate) {

    fadeAmount = constrain(fadeAmount, 0, 255);

    switch (currentState) {
      case fullOff:
        fadeAmount += fadeRate;
        analogWrite(ledPin, fadeAmount);
        delay(fadeSpeed);

        if (fadeAmount >= 255) {
          currentState = fullOn;
        }
        break;

      case fullOn:
        fadeAmount = fadeAmount - fadeRate;
        analogWrite(ledPin, fadeAmount);
        delay(fadeSpeed);

        if (fadeAmount <= 0) {
          currentState = fullOff;
        }
        break;
    }

    Serial.println(fadeAmount);
  }
};

FADE greenFade;
FADE redFade;
FADE blueFade;
FADE yellowFade;

void setup() {
  // put your setup code here, to run once:
  pinMode(greenLed, OUTPUT);
  pinMode(redLed, OUTPUT);
  pinMode(blueLed, OUTPUT);
  pinMode(yellowLed, OUTPUT);

  Serial.begin(9600);
}

void loop() {
  greenFade.fadeLed(greenLed, 30, 20);
  redFade.fadeLed(redLed, 30, 10);
  blueFade.fadeLed(blueLed, 30, 15);
  yellowFade.fadeLed(yellowLed, 30, 25);
}