#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <MPU6050_tockn.h>

LiquidCrystal_I2C lcd(0x27, 16, 2); // Address 0x27, 16 columns, 2 rows
MPU6050 mpu6050(Wire);

const int trigPin = 7;
const int echoPin = 6;
const int buzzerPin = 2;

int maxSpeed = 60; // Set your maximum allowed speed in km/h
int safeDistance = 20; // Set your safe following distance in centimeters

void setup() {
  lcd.init();
  lcd.backlight();
  Wire.begin();
  mpu6050.begin();
  mpu6050.calcGyroOffsets(true);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(buzzerPin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  float accX = mpu6050.getAccX() / 16384.0;
  float speed = accX * 100; // Assuming you've calibrated it properly
  float distance = getDistance();

  lcd.setCursor(0, 0);
  lcd.print("Speed: " + String(speed) + " km/h");
  lcd.setCursor(0, 1);
  lcd.print("Distance: " + String(distance) + " cm");

  if (speed > maxSpeed) {
    // Display overspeed warning on the LCD
    lcd.setCursor(0, 1);
    lcd.print("Overspeed!");

    // Activate the buzzer to indicate overspeed
    tone(buzzerPin, 1000); // You can change the tone and duration

    // Implement accident-avoidance logic here
    if (distance < safeDistance) {
      // Implement automatic braking or avoidance maneuver here
      // For simulation purposes, you can print a message or take a specific action
      Serial.println("Collision imminent! Applying brakes.");
    }
  } else {
    noTone(buzzerPin);
  }

  delay(1000); // Update every second
}

float getDistance() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  long duration = pulseIn(echoPin, HIGH);
  float cm = duration * 0.034 / 2;

  return cm;
}