Fade in and out an LED by pressing a button. Fun times

switchy.ino

int led = 11;
int buttonPin = 2;
int buttonState = 0;
bool wasOn = false;
bool isOn = false;
bool wasPressed = false;

void setup() {
  pinMode(led, OUTPUT);
  pinMode(buttonPin, INPUT);
  Serial.begin(9600);
}

void loop() {
  buttonState = digitalRead(buttonPin);
  Serial.println(buttonState);
//  digitalWrite(led, buttonState);

  if (buttonState == HIGH) {
    wasPressed = true;
  } else {
    wasOn = isOn;
    if (wasPressed) {
      isOn = !isOn;
    }
    wasPressed = false;
  }
  
  if (isOn) {
    if (!wasOn) {
      fadeIn(led, 640);
    } else {
      digitalWrite(led, HIGH);
    }
  } else {
    if (wasOn) {
      fadeOut(led, 640);
    } else {
      digitalWrite(led, LOW);
    }
  }
}

void blink(int pin, int times, int duration) {
  for (int i = 0; i < times; i++) {
    digitalWrite(pin, HIGH);
    delay(duration);
    digitalWrite(pin, LOW);
    delay(duration);
  }
}

void fadeIn(int pin, unsigned long duration) {
  for (int i = 0; i <= 255; i++) {
    analogWrite(pin, i);
    delay(duration/255);
  }
}

void fadeOut(int pin, unsigned long duration) {
  for (int i = 255; i >= 0; i--) {
    analogWrite(pin, i);
    delay(duration/255);
  }
}