#include <LiquidCrystal.h>

#define echoPinl 2 // attach pin D2 Arduino to pin Echo of HC-SR04
#define echoPinm 4
#define echoPinr 5
#define trigPinl 6 // attach pin D6 Arduino to pin Trig of HC-SR04 for left sensor
#define trigPinm 13 // attach pin D7 Arduino to pin Trig of HC-SR04 for middle sensor
#define trigPinr 3 // attach pin D8 Arduino to pin Trig of HC-SR04 for right sensor

LiquidCrystal lcd(12, 11, 10, 9, 8, 7);

// defines variables
long durationl; // variable for the duration of sound wave travel
long durationm;
long durationr;
int distancel; // variable for the distance measurement
int distancem;
int distancer;

void setup() {
  pinMode(trigPinl, OUTPUT); // Sets the trigPinl as an OUTPUT
  pinMode(trigPinm, OUTPUT); // Sets the trigPinm as an OUTPUT
  pinMode(trigPinr, OUTPUT); // Sets the trigPinr as an OUTPUT
  pinMode(echoPinl, INPUT);
  pinMode(echoPinm, INPUT);
  pinMode(echoPinr, INPUT); // Sets the echoPin as an INPUT

  lcd.begin(16, 2); // Initialize the LCD with 16 columns and 2 rows
  Serial.begin(9600); // Initialize Serial communication for debugging
}

void loop() {
  // Measure left sensor
  distancel = getDistance(trigPinl, echoPinl);

  // Delay before measuring middle sensor
  delay(10);

  // Measure middle sensor
  distancem = getDistance(trigPinm, echoPinm);

  // Delay before measuring right sensor
  delay(10);

  // Measure right sensor
  distancer = getDistance(trigPinr, echoPinr);
  
  // Clear LCD before printing new readings
  lcd.clear();
  
  // Print distances on LCD
  lcd.setCursor(0, 0);
  lcd.print("L: ");
  lcd.print(distancel);
  lcd.setCursor(7, 0);
  lcd.print("M: ");
  lcd.print(distancem);
  lcd.setCursor(0, 1);
  lcd.print("R: ");
  lcd.print(distancer);

  // Debugging output
  Serial.print("Left: ");
  Serial.print(distancel);
  Serial.print(" | Middle: ");
  Serial.print(distancem);
  Serial.print(" | Right: ");
  Serial.println(distancer);

  delay(250); // Delay between sensor readings (adjust as needed)
}

int getDistance(int trigPin, int echoPin) {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  long duration = pulseIn(echoPin, HIGH);
  int distance = duration * 0.034 / 2;
  return distance;
}