#include <Servo.h>

Servo vikingsServo;
int potPin = A0;
int buttonPin = 2;
int ledPin = 13;
bool isRunning = false;

void setup() {
  vikingsServo.attach(9);
  pinMode(potPin, INPUT);
  pinMode(buttonPin, INPUT_PULLUP);
  pinMode(ledPin, OUTPUT);
}

void loop() {
  if (digitalRead(buttonPin) == LOW) {
    isRunning = !isRunning;
    delay(300); // debounce
  }

  if (isRunning) {
    digitalWrite(ledPin, HIGH);
    int potValue = analogRead(potPin);
    int angle = map(potValue, 0, 1023, 60, 120); // swing range
    vikingsServo.write(angle);
    delay(100);
    vikingsServo.write(180 - angle);
    delay(100);
  } else {
    digitalWrite(ledPin, LOW);
    vikingsServo.write(90); // neutral position
  }
}