#include <Wire.h>
#include <LiquidCrystal.h>
#include <Servo.h>

Servo servo;  // Create servo object to control a servo
#define LED_PIN 13 // Pin for the LED

int val;
int pos = 0;    // Variable to store the servo position

int sensor = 1;  // The pin that the sensor is attached to

const int rs = 12, en = 11, d4 = 10, d5 = 9, d6 = 8, d7 = 7;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);
int ab;

const int DOUT_PIN = 2; // Pin connected to the DOUT pin of the load cell
const int CLK_PIN = 3;  // Pin connected to the CLK pin of the load cell

const float MAX_WEIGHT = 10; // Maximum weight in kilograms
bool carDetected = false;
unsigned long carDetectedTime = 0; // Variable to store the time when the car was detected

void setup() {
  lcd.begin(20, 4);
  pinMode(sensor, INPUT);
  pinMode(LED_PIN, OUTPUT);
  servo.attach(4);

  // Initialize the load cell module
  pinMode(DOUT_PIN, INPUT);
  pinMode(CLK_PIN, OUTPUT);
  
  // Wait for the load cell module to stabilize
  delay(1000);
}

void loop() {
  val = digitalRead(sensor);   // Read sensor value

  // Read the weight from the load cell
  float weight = getWeight();

  // Display the weight on the LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Weight: ");
  lcd.setCursor(0, 1);
  lcd.print(weight, 1);
  lcd.print(" kg");

  // Check if the weight exceeds the maximum limit
  if (weight > MAX_WEIGHT) {
    digitalWrite(LED_PIN, HIGH); // Turn on the LED
    delay(1000); // Wait for 1 second
    digitalWrite(LED_PIN, LOW); // Turn off the LED
    lcd.setCursor(0, 2);
    lcd.print("CHANGE ROAD OR TURN BACK");
    carDetected = false;
  } else if (val == LOW && !carDetected) {
    openBarrier();
    carDetected = true;
    carDetectedTime = millis(); // Record the time when the car was detected
  } else if (carDetected && millis() - carDetectedTime >= 10000) {
    closeBarrier();
    carDetected = false;
  }

  delay(1000);
}

float getWeight() {
  unsigned long value = 0;

  // Read 24 bits of data from the load cell
  for (byte i = 0; i < 24; i++) {
    digitalWrite(CLK_PIN, HIGH);
    delayMicroseconds(0.5);
    value <<= 1;
    if (digitalRead(DOUT_PIN)) {
      value++;
    }
    digitalWrite(CLK_PIN, LOW);
    delayMicroseconds(0.5);
  }

  // Set the MSB (bit 24) to 0 for a positive value
  value &= 0x7FFFFF;

  // Calculate the weight in kilograms
  float weight = value / 100;

  return weight;
}

void openBarrier() {
  for (pos = 0; pos <= 90; pos += 1) {
    servo.write(pos);
    delay(10);
  }
}

void closeBarrier() {
  for (pos = 90; pos >= 0; pos -= 1) {
    servo.write(pos);
    delay(10);
  }
}