/**
   Mini piano for Arduino.

   You can control the colorful buttons with your keyboard:
   After starting the simulation, click anywhere in the diagram to focus it.
   Then press any key between 1 and 8 to play the piano (1 is the lowest note,
   8 is the highest).

   Copyright (C) 2021, Uri Shaked. Released under the MIT License.
*/

const int trigPin = 9; // Trigger pin of ultrasonic sensor
const int echoPin = 10; // Echo pin of ultrasonic sensor
const int numLeds = 5; // Number of LEDs to control
const int ledPins[numLeds] = {2, 3, 4, 5, 6}; // Pins connected to the LEDs
const int distanceThresholds[numLeds + 1] = {200, 250, 300, 350, 410}; // Distance thresholds for each LED

void setup() {
  Serial.begin(9600);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  for (int i = 0; i < numLeds; i++) {
    pinMode(ledPins[i], OUTPUT);
  }
}

void loop() {
  long duration, distance;
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = (duration * 0.0343) / 2; // Convert the time into distance

  Serial.print("Distance: ");
  Serial.println(distance);

  // Turn off all LEDs
  for (int i = 0; i < numLeds; i++) {
    digitalWrite(ledPins[i], LOW);
  }

  // Turn on the appropriate LED based on distance
  for (int i = 0; i < numLeds; i++) {
    if (distance >= distanceThresholds[i] && distance < distanceThresholds[i + 1]) {
      digitalWrite(ledPins[i], HIGH);
      break; // Exit loop once LED is turned on
    }
  }
  
  delay(500); // Delay for stability
}