#include <LiquidCrystal_I2C.h>
#include <Servo.h>

Servo front;  // front door
Servo back;  // back door
LiquidCrystal_I2C lcd(0x27, 20, 4);

int echo_back  = 2;
int trig_back = 3; // back
int echo_front = 4;
int trig_front = 5;  // front
long distance;
long distance1;

int irFront = A0; // IR sensor at front door
int irBack = A1;  // IR sensor at back door
int irFrontReading;
int irBackReading;

int buzzerFront = 12; // Front door
int buzzerBack = 13; // Back door

int RELAYFront = 11;  //  front door
int RELAYBack = 8;  //  back door

bool frontDetected = false;
bool backDetected = false;
bool displayingSystemAutomation = true;
bool frontDoorOpen = false;
bool backDoorOpen = false;

void setup() {
  Serial.begin(9600);

  lcd.clear();
  lcd.init();
  lcd.backlight();

  pinMode(echo_back, INPUT);
  pinMode(echo_front, INPUT);
  pinMode(trig_back, OUTPUT);
  pinMode(trig_front, OUTPUT);
  pinMode(RELAYFront, OUTPUT);
  pinMode(RELAYBack, OUTPUT);
  pinMode(buzzerFront, OUTPUT);
  pinMode(buzzerBack, OUTPUT);
  pinMode(irFront, INPUT);
  pinMode(irBack, INPUT);

  front.attach(9);
  back.attach(10);
}

void loop() {
  lcd.clear();

  digitalWrite(trig_back, LOW);
  delay(10);
  digitalWrite(trig_back, HIGH);
  delay(10);
  digitalWrite(trig_back, LOW);
  distance = pulseIn(echo_back, HIGH) * 0.034 / 2;

  digitalWrite(trig_front, LOW);
  delay(10);
  digitalWrite(trig_front, HIGH);
  delay(10);
  digitalWrite(trig_front, LOW);
  distance1 = pulseIn(echo_front, HIGH) * 0.034 / 2;

  irFrontReading = analogRead(irFront);
  irBackReading = analogRead(irBack);

  int irThreshold = 500; // adjust this value to your liking

  if (irFrontReading <= irThreshold) {
    irFrontReading = irFrontReading;
  } else {
    irFrontReading = irThreshold + (irFrontReading - irThreshold);
  }

  if (irBackReading <= irThreshold) {
    irBackReading = irBackReading;
  } else {
    irBackReading = irThreshold + (irBackReading - irThreshold);
  }

  if (distance1 <= 15 && distance1 > 0) {
    frontDetected = true;
  } else {
    frontDetected = false;
  }

  if (distance <= 15 && distance > 0) {
    backDetected = true;
  } else {
    backDetected = false;
  }

  if (frontDetected) {
    tone(buzzerFront, 300);
    digitalWrite(RELAYFront, HIGH);
    lcd.print("Intruder at front: ");
    lcd.print(distance1);
    lcd.print(" cm");
    lcd.setCursor(1, 1);
    lcd.print("IR Reading: ");
    lcd.print(irFrontReading);
    for (int i = 0; i <= 90; i++) {
      front.write(i);
      delay(10);
    }
    frontDoorOpen = true;
  }

  if (backDetected) {
    tone(buzzerBack, 500);
    digitalWrite(RELAYBack, HIGH);
    lcd.setCursor(1, 0);
    lcd.print("Intruder at back: ");
    lcd.setCursor(1,2);
    lcd.print(distance);
    lcd.print(" cm");
    lcd.setCursor(1, 3);
    lcd.print("IR Reading: ");
    lcd.print(irBackReading);
    for (int i = 0; i <= 90; i++) {
      back.write(i);
      delay(10);
    }
    backDoorOpen = true;
  }

  if (!frontDetected && frontDoorOpen) {
    for (int i = 90; i >= 0; i--) {
      front.write(i);
      delay(10);
    }
    digitalWrite(RELAYFront, LOW);
    noTone(buzzerFront);
    frontDoorOpen = false;
  }

  if (!backDetected && backDoorOpen) {
    for (int i = 90; i >= 0; i--) {
      back.write(i);
      delay(10);
    }
    digitalWrite(RELAYBack, LOW);
    noTone(buzzerBack);
    backDoorOpen = false;
  }

  if (!frontDetected && !backDetected) {
    lcd.clear();
    lcd.print("Home Automation");
    lcd.backlight();
  }

  delay(250);
}