const int trigPin = 9;
const int echoPin = 10;
const int MIN_DISTANCE = 10;
const int MAX_DISTANCE = 350;

long duration;
int distance;

void setup() {
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  Serial.begin(9600);
}

int measureDistance() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  duration = pulseIn(echoPin, HIGH);
  distance = duration * 0.034 / 2;
  
  if (distance < MIN_DISTANCE || distance > MAX_DISTANCE) {
    return -1; // Invalid distance
  }
  
  return distance;
}

const int buzzerPin = 11;
const int numNotes = 8;
const int frequencies[] = {262, 294, 330, 349, 392, 440, 494, 523}; // C4 to C5


void playNote(int frequency) {
  tone(buzzerPin, frequency);
  delay(200);
  noTone(buzzerPin);
}

int mapDistanceToNote(int distance) {
  int note = map(distance, 10, 50, 0, numNotes - 1);
  note = constrain(note, 0, numNotes - 1);
  return note;
}

int lastDistance = 0;
unsigned long lastMeasureTime = 0;
const int skipThreshold = 10; // cm/s

bool shouldSkipNote(int currentDistance) {
  unsigned long currentTime = millis();
  float timeDiff = (currentTime - lastMeasureTime) / 1000.0;
  float speed = abs(currentDistance - lastDistance) / timeDiff;
  
  lastDistance = currentDistance;
  lastMeasureTime = currentTime;
  
  return speed > skipThreshold;
}

void printStatus(int distance, int note) {
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.print(" cm | Note: ");
  Serial.println(frequencies[note]);
}
void loop() {
  int currentDistance = measureDistance();
  int currentNote = mapDistanceToNote(currentDistance);
  
  printStatus(currentDistance, currentNote);
  
  if (!shouldSkipNote(currentDistance)) {
    playNote(frequencies[currentNote]);
  }
  
  delay(50); // Adjust this delay to control sensitivity
}