int stato = 0;
void setup() {
  Serial.begin(115200);
  // put your setup code here, to run once:
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(16, INPUT_PULLUP);
  pinMode(17, INPUT_PULLUP);
  pinMode(18, INPUT_PULLUP);
  pinMode(19, INPUT_PULLUP);
}
void  loop()  {
  switch(stato){
    case 0:
      chiuso();
      break;
    case 1:
      apertura();
      break;
    case 2:
      aperto();
      break;
    case 3:
      chiusura();
      break;
  }
}
void chiuso ()  {
  if (! digitalRead(16)){
    Serial.println("apertura");
    digitalWrite(4, HIGH);
    delay(300);
    stato = 1;
  }
}
void apertura ()  {
  if (! digitalRead(18)){
    Serial.println("aperto");
    digitalWrite(4, LOW);
    delay(300);
    stato = 2;
    }
  if (!digitalRead(17)){
    Serial.println("mi sto richiudendo");
     digitalWrite(5, HIGH);
     digitalWrite(4, LOW);
    delay(300);
    stato = 3;
    }
}
void aperto () {
  if (! digitalRead(17)){
    Serial.println("chiusura");
    digitalWrite(5, HIGH);
    delay(300);
    stato = 3;
  }
}
void chiusura () {
  if (! digitalRead(19)){
    Serial.println("chiuso");
    digitalWrite(5,LOW);
    delay(300);
    stato = 0;
  }
}