#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <DHT.h>
#include <RTClib.h>
#include <Servo.h>

// Pin assignments
const int pirPin = 2;          // PIR Motion Sensor
const int dhtPin = 3;          // DHT22 Sensor
const int ldrPin = A0;         // LDR (Photoresistor)
const int ledPin = 4;          // LED for light control
const int alertLedPin = 5;     // LED for security alert
const int acLedPin = 6;        // LED for air conditioner
const int curtainLedPin = 7;   // LED for curtains
const int buzzerPin = 8;       // Buzzer
const int servoPin = 10;       // Servo motor for smart lock
const int buttonPin = 11;      // Push button for manual lock/unlock
const int dataPin = 13;        // Connects to pin 14 on the 74HC595
const int clockPin = 12;       // Connects to pin 11 on the 74HC595
const int latchPin = 9;        // Connects to pin 12 on the 74HC595

// Shift Register Pins
const int secondPirPin = 1;   // Q1 on the 74HC595 shift register
const int newLedPin = 2;      // Q2 on the 74HC595 shift register

// DHT setup
#define DHT_TYPE DHT22
DHT dht(dhtPin, DHT_TYPE);

// LCD setup
LiquidCrystal_I2C lcd(0x27, 16, 2);

// RTC setup
RTC_DS1307 rtc;

// Servo setup
Servo myServo;
bool lockState = false; // false = unlocked, true = locked

// Shift Register state
byte shiftRegisterState = 0;

// Function prototypes
void displayInitialMessage();
void initializeSystem();
void readSensors();
void updateLcdDisplay(float temperature, float humidity);
void controlLights(int ldrValue);
void handleSecurityAlert(int pirState);
void controlAirConditioner(float temperature);
void controlCurtains(DateTime now);
void controlDoorLock();
void toggleLock();
void updateShiftRegister();
void handleSecondMotionSensor();

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

  pinMode(pirPin, INPUT);
  pinMode(ldrPin, INPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(alertLedPin, OUTPUT);
  pinMode(acLedPin, OUTPUT);
  pinMode(curtainLedPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
  pinMode(buttonPin, INPUT_PULLUP);
  pinMode(dataPin, OUTPUT);
  pinMode(clockPin, OUTPUT);
  pinMode(latchPin, OUTPUT);

  dht.begin();
  lcd.init();
  lcd.backlight();

  myServo.attach(servoPin);
  myServo.write(0); // Start with the door unlocked

  // Initialize RTC
  if (!rtc.begin()) {
    Serial.println("Couldn't find RTC");
    while (1);
  }
  if (!rtc.isrunning()) {
    Serial.println("RTC is NOT running!");
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }

  displayInitialMessage();
  initializeSystem();
}

void loop() {
  readSensors();
  DateTime now = rtc.now();
  controlCurtains(now);
  controlDoorLock();
  handleSecondMotionSensor(); // Handle second motion sensor
  delay(2000); // Wait for 2 seconds before next loop
}

void displayInitialMessage() {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Smart Home System");
  lcd.setCursor(0, 1);
  lcd.print("Initializing...");
  delay(2000);
}

void initializeSystem() {
  digitalWrite(ledPin, LOW);
  digitalWrite(alertLedPin, LOW);
  digitalWrite(acLedPin, LOW);
  digitalWrite(curtainLedPin, LOW);
  digitalWrite(buzzerPin, LOW);
}

void readSensors() {
  // Read PIR sensor
  int pirState = digitalRead(pirPin);

  // Read DHT22 sensor
  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();

  // Read LDR sensor
  int ldrValue = analogRead(ldrPin);

  // Read second PIR sensor
  bool secondPirState = bitRead(shiftRegisterState, secondPirPin);

  // Print values to Serial Monitor
  Serial.print("PIR: ");
  Serial.print(pirState);
  Serial.print("\tSecond PIR: ");
  Serial.print(secondPirState);
  Serial.print("\tTemperature: ");
  Serial.print(temperature);
  Serial.print("°C\tHumidity: ");
  Serial.print(humidity);
  Serial.print("%\tLDR: ");
  Serial.println(ldrValue);

  // Update LCD display
  updateLcdDisplay(temperature, humidity);

  // Control lights based on LDR value
  controlLights(ldrValue);

  // Handle security alert based on PIR sensor
  handleSecurityAlert(pirState);

  // Control air conditioner based on temperature
  controlAirConditioner(temperature);
}

void updateLcdDisplay(float temperature, float humidity) {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(temperature);
  lcd.print("C");
  lcd.setCursor(0, 1);
  lcd.print("Humidity: ");
  lcd.print(humidity);
  lcd.print("%");
}

void controlLights(int ldrValue) {
  if (ldrValue < 500) {
    digitalWrite(ledPin, HIGH); // Turn on LED if it's dark
  } else {
    digitalWrite(ledPin, LOW); // Turn off LED if it's light
  }
}

void handleSecurityAlert(int pirState) {
  if (pirState == HIGH) {
    for (int i = 0; i < 10; i++) {
      tone(8, 800); // Sound buzzer
      digitalWrite(alertLedPin, HIGH);
      delay(50);
      noTone(8);
      digitalWrite(alertLedPin, LOW);
      delay(150);
      tone(8, 900);
      digitalWrite(alertLedPin, HIGH);
      delay(50);
      noTone(8);
      digitalWrite(alertLedPin, LOW);
    }
  } else {
    digitalWrite(alertLedPin, LOW);
    noTone(8);
  }
}

void controlAirConditioner(float temperature) {
  if (temperature > 27.0) {
    digitalWrite(acLedPin, HIGH); // Turn on AC (represented by LED)
  } else {
    digitalWrite(acLedPin, LOW); // Turn off AC (represented by LED)
  }
}

void controlCurtains(DateTime now) {
  if (now.hour() >= 7 && now.hour() < 19) {
    digitalWrite(curtainLedPin, LOW); // Open curtains (represented by LED)
  } else {
    digitalWrite(curtainLedPin, HIGH); // Close curtains (represented by LED)
  }
}

void controlDoorLock() {
  if (digitalRead(buttonPin) == LOW) {
    toggleLock();
    delay(500); // Debounce delay
  }
}

void toggleLock() {
  if (lockState) {
    myServo.write(0); // Unlock door
    lockState = false;
  } else {
    myServo.write(90); // Lock door
    lockState = true;
  }
}

void updateShiftRegister() {
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, MSBFIRST, shiftRegisterState);
  digitalWrite(latchPin, HIGH);
}

void handleSecondMotionSensor() {
  bool motionDetected = bitRead(shiftRegisterState, secondPirPin);

  if (motionDetected) {
    bitSet(shiftRegisterState, newLedPin); // Turn on new LED
    updateShiftRegister();
    delay(6000); // Keep the LED on for 6 seconds
    bitClear(shiftRegisterState, newLedPin); // Turn off new LED
    updateShiftRegister();
  }
}