#define ledPin 2
#define ledPin1 3
#define buttonPin 12
#define skracovanie 100
bool ledState=0;
bool buttonState=0;
bool lastButtonState=0;
unsigned long lastDebounceTime=0;
unsigned long previousMillis=0;
int debounceDelay=50;
int interval=5000;

void setup() {
  pinMode(buttonPin, INPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(ledPin1,OUTPUT);
  digitalWrite(ledPin, ledState);
  digitalWrite(ledPin1, !ledState);
  Serial.begin(9600);
  Serial.println("Interval blikanie je "+String(interval)+" ms");
}

void loop() {
  bool reading = digitalRead(buttonPin);
  if (reading != lastButtonState) {
    lastDebounceTime = millis();
  }
  if ((millis() - lastDebounceTime) > debounceDelay) {
    if (reading != buttonState) {
      buttonState = reading;
      if (buttonState == HIGH) {
        Serial.println("Interval blikanie je "+String(interval=(interval<=skracovanie?5000:interval-skracovanie))+" ms");
      }
    }
  }
  unsigned long currentMillis=millis();
  if(currentMillis-previousMillis>=interval){
    previousMillis=currentMillis;
    ledState=!ledState;
    digitalWrite(ledPin, ledState);
    digitalWrite(ledPin1, !ledState);
  }
  lastButtonState = reading;
}