const int pwmPin = 1;       // pwnPin number conencted to MCU
const int buttonPin = 4;   // the number of the pushbutton pin
const int analogPin = A3; // battery voltage monitor resistor connected to analog pin 3

int var = 4;               //default
int lastButtonState = LOW;  // the previous reading from the input pin
int buttonState;             // the current reading from the input pin
unsigned long lastDebounceTime = 0;  // the last time the output pin was toggled
unsigned long debounceDelay = 150;    // the debounce time; increase if the output flickers


void setup() {
  pinMode(buttonPin, INPUT_PULLUP);
  pinMode(2, OUTPUT);    // sets the digital pin 2 as output
}

void loop() {
  // read the state of the switch into a local variable:
  int reading = digitalRead(buttonPin);

  // check to see if you just pressed the button
  // (i.e. the input went from HIGH to LOW), and you've waited long enough
  // since the last press to ignore any noise:

  // If the switch changed, due to noise or pressing:
  if (reading != lastButtonState) {
    // reset the debouncing timer
    lastDebounceTime = millis();
  }

  if ((millis() - lastDebounceTime) > debounceDelay) {
    // whatever the reading is at, it's been there for longer than the debounce
    // delay, so take it as the actual current state:

    // if the button state has changed:
    if (reading != buttonState) {
      buttonState = reading;

      // only toggle the LED if the new button state is HIGH
      if (buttonState == LOW) {
        var = var + 1;
        if (var >= 5) {
          var = 1;
        }
      }
    }
  }
  // save the reading. Next time through the loop, it'll be the lastButtonState:
  lastButtonState = reading;

  switch (var) {
    case 1:
      analogWrite(pwmPin, 0);
      digitalWrite(0, HIGH);

      break;
    case 2:
      analogWrite(pwmPin, 255);
      digitalWrite(0, LOW);
      break;

    case 3:
      analogWrite(pwmPin, 10);
      digitalWrite(0, HIGH);
      break;

    case 4:
      analogWrite(pwmPin, 0);
      digitalWrite(0, LOW);
      
      break;


    default:

      // if nothing else matches, do the default
      // default is optional
      break;
  }
  
}