const int numLEDs = 10;       // Number of LEDs in the strip
const int ledPins[numLEDs] = {2, 3, 4, 5, 6, 7, 8, 9, 10, 11}; // Pins connected to LEDs
int delayTime = 500;         // Initial delay time in milliseconds (2 seconds)
int minDelayTime = 0;       // Minimum delay time (250 milliseconds)
int delayStep =  100;          // Step to decrease or increase delay time
bool decreasing = true;       // To keep track of delay decreasing/increasing

void setup() {
  Serial.begin(9600);         // Initialize serial communication at 9600 baud rate
  Serial.println("LED Chase Initialized");
  
  for (int i = 0; i < numLEDs; i++) {
    pinMode(ledPins[i], OUTPUT); // Set each LED pin as output
    digitalWrite(ledPins[i], LOW); // Turn off all LEDs initially
  }
}

void loop() {
  // LED Chase forward
  for (int i = 0; i < numLEDs; i++) {
    digitalWrite(ledPins[i], HIGH);   // Turn on the current LED
    delay(delayTime);                 // Delay for the current delayTime
    digitalWrite(ledPins[i], LOW);    // Turn off the current LED
  }
  
  // LED Chase backward
  for (int i = numLEDs - 1; i >= 0; i--) {
    digitalWrite(ledPins[i], HIGH);   // Turn on the current LED
    delay(delayTime);                 // Delay for the current delayTime
    digitalWrite(ledPins[i], LOW);    // Turn off the current LED
  }

  // Print current delay time to serial monitor
  Serial.print("Current delay time: ");
  Serial.println(delayTime);

  // Update delay time
  if (decreasing) {
    delayTime -= delayStep;           // Decrease delay time
    if (delayTime <= minDelayTime) {
      decreasing = false;             // Switch to increasing mode
    }
  } else {
    delayTime += delayStep;           // Increase delay time
    if (delayTime >= 600) {
      decreasing = true;              // Switch to decreasing mode again
    }
  }
}