#include <LiquidCrystal_I2C.h>
#include <DHT.h>

// Define pins for IR sensors, LDR, and LEDs
const int IR1 = 8, IR2 = 12, IR3 = 2, LDR = 7, led1 = 6, led2 = 5, led3 = 3;
const int ir_s1 = 9, ir_s2 = 10;

// Define variables for sensor values and brightness
int val1, val2, val3, val4;
int brit = 10; // Brightness for LEDs

// LCD initialization: 16 columns and 2 rows, I2C address 0x27 and 0x26
LiquidCrystal_I2C lcd1(0x27, 16, 2); // LCD1 for temperature display
LiquidCrystal_I2C lcd2(0x26, 16, 2); // LCD2 for speed display

// Initialize DHT sensor
#define DHTPIN A0     // Analog pin connected to the DHT sensor
#define DHTTYPE DHT22 // DHT 22 sensor
DHT dht(DHTPIN, DHTTYPE); // Create DHT object

// Variables to store the time when the IR sensors are triggered
unsigned long timer1;
unsigned long timer2;

// Variable to store the time difference between the two triggers
float Time;

// Flags to indicate if the sensors have been triggered
int flag1 = 0;
int flag2 = 0;

// Distance between the two IR sensors in meters
float distance = 5.0;

// Variable to store the calculated speed
float speed;

void setup() {
  // Initialize pins
  pinMode(IR1, INPUT);
  pinMode(IR2, INPUT);
  pinMode(IR3, INPUT);
  pinMode(LDR, INPUT);
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(led3, OUTPUT);
  pinMode(ir_s1, INPUT);
  pinMode(ir_s2, INPUT);
  
  // Initialize serial communication for debugging
  Serial.begin(9600);

  // Initialize the first LCD
  lcd1.init();
  lcd1.backlight();

  // Initialize the second LCD
  lcd2.init();
  lcd2.backlight();

  // Initialize DHT sensor
  dht.begin();
}

void loop() {
  // Read sensor values
  val1 = digitalRead(IR1);
  val2 = digitalRead(IR2);
  val3 = digitalRead(IR3);
  val4 = digitalRead(LDR);
  int ir_s1_val = digitalRead(ir_s1);
  int ir_s2_val = digitalRead(ir_s2);
  
  // Read temperature and humidity sensor values
  float temperatureC = dht.readTemperature();
  
  // Print sensor values and temperature to serial monitor
  Serial.print("IR1: "); Serial.print(val1);
  Serial.print(" | IR2: "); Serial.print(val2);
  Serial.print(" | IR3: "); Serial.print(val3);
  Serial.print(" | LDR: "); Serial.print(val4);
  Serial.print(" | Temp: "); Serial.print(temperatureC); Serial.println(" C");
  Serial.print(" | IR_S1: "); Serial.print(ir_s1_val);
  Serial.print(" | IR_S2: "); Serial.println(ir_s2_val);

  // Display temperature on the first LCD
  lcd1.clear();
  lcd1.setCursor(0, 0);
  lcd1.print("Temp: "); lcd1.print(temperatureC); lcd1.print(" C");

  // Control LEDs based on sensor values
  if (val1 == 0 && val2 == 0 && val3 == 0 && val4 == 0) {
    // All sensors are inactive
    digitalWrite(led1, LOW);
    digitalWrite(led2, LOW);
    digitalWrite(led3, LOW);
  } else if (val1 == 1 && val2 == 1 && val3 == 1 && val4 == 0) {
    // Specific condition with all IR sensors active but LDR inactive
    digitalWrite(led1, LOW);
    digitalWrite(led2, LOW);
    digitalWrite(led3, LOW);
  } else if (val1 == 0 && val2 == 0 && val3 == 0 && val4 == 1) {
    // LDR active, all IR sensors inactive
    analogWrite(led1, brit);
    analogWrite(led2, brit);
    analogWrite(led3, brit);
  } else if (val1 == 1 && val2 == 0 && val3 == 0 && val4 == 1) {
    // Specific condition with IR1 and LDR active
    analogWrite(led1, 255);
    analogWrite(led2, brit);
    analogWrite(led3, brit);
  } else if (val1 == 0 && val2 == 1 && val3 == 0 && val4 == 1) {
    // Specific condition with IR2 and LDR active
    analogWrite(led1, brit);
    analogWrite(led2, 255);
    analogWrite(led3, brit);
  } else if (val1 == 0 && val2 == 0 && val3 == 1 && val4 == 1) {
    // Specific condition with IR3 and LDR active
    analogWrite(led1, brit);
    analogWrite(led2, brit);
    analogWrite(led3, 255);
  } else if (val1 == 1 && val2 == 1 && val3 == 1 && val4 == 1) {
    // All sensors are active
    analogWrite(led1, 255);
    analogWrite(led2, 255);
    analogWrite(led3, 255);
  }

  // Speed measurement logic for the second LCD
  if (ir_s1_val == LOW ) {
    // First IR sensor triggered
    timer1 = millis(); // Record the time
    delay(100);
    flag1 = 1; // Set the flag to indicate the sensor was triggered
  }

  if (ir_s2_val == LOW ) {
    // Second IR sensor triggered
    timer2 = millis(); // Record the time
    delay(100);
    flag2 = 1; // Set the flag to indicate the sensor was triggered
  }

  if (flag1 == 1 && flag2 == 1) {
    // Both IR sensors have been triggered
    if (timer1 > timer2) {
      Time = (timer1 - timer2) / 1000.0; // Convert milliseconds to seconds
    } else {
      Time = (timer2 - timer1) / 1000.0; // Convert milliseconds to seconds
    }
    speed = (distance / Time); // Calculate speed in meters per second
    speed = speed * 3.6; // Convert speed to kilometers per hour
  }

  if (speed == 0) {
    // No speed calculated yet
    lcd2.setCursor(0, 0);
    if (flag1 == 0 && flag2 == 0) {
      lcd2.print("No car detected");
    lcd2.setCursor(0, 1);
      lcd2.print("Searching...    ");
    }
  } else {
    // Display the calculated speed
    lcd2.clear();
    lcd2.setCursor(0, 0);
    lcd2.print("Speed:");
    lcd2.print(speed, 1);
    lcd2.print(" Km/Hr  ");
    lcd2.setCursor(0, 1);
    delay(3000);
    if (speed > 50) {
      lcd2.print("  Over Speeding  ");
    } else {
      lcd2.print("  Normal Speed   ");
    }
    speed = 0; // Reset the speed
    flag1 = 0; // Reset the flag for the first sensor
    flag2 = 0; // Reset the flag for the second sensor
  }
}