// Include the libraries
#include <DHT.h>
#include <LiquidCrystal.h>

// Define the pins
#define DHTPIN 4 // DHT22 data pin
#define DHTTYPE DHT22 // DHT22 sensor type
#define PIR1 12 // PIR sensor 1 pin
#define PIR2 13 // PIR sensor 2 pin
#define PIR3 14 // PIR sensor 3 pin
#define PIR4 15 // PIR sensor 4 pin
#define LED1 16 // LED 1 pin
#define LED2 17 // LED 2 pin
#define LED3 18 // LED 3 pin
#define RS 19 // LCD RS pin
#define EN 21 // LCD EN pin
#define D4 22 // LCD D4 pin
#define D5 23 // LCD D5 pin
#define D6 25 // LCD D6 pin
#define D7 26 // LCD D7 pin

// Initialize the objects
DHT dht(DHTPIN, DHTTYPE); // DHT22 object
LiquidCrystal lcd(RS, EN, D4, D5, D6, D7); // LCD object

// Define the constants
const float optTemp = 25.0; // Optimum temperature
const int delayTime = 2000; // Delay time

// Define the variables
float temp; // Temperature
float hum; // Humidity
bool pir1; // PIR sensor 1 state
bool pir2; // PIR sensor 2 state
bool pir3; // PIR sensor 3 state
bool pir4; // PIR sensor 4 state
bool ac; // Air conditioner state
bool lamp1; // Lamp 1 state
bool lamp2; // Lamp 2 state

void setup() {
  // Initialize the serial monitor
  Serial.begin(9600);

  // Initialize the DHT22 sensor
  dht.begin();

  // Initialize the LCD display
  lcd.begin(16, 2);

  // Initialize the pins
  pinMode(PIR1, INPUT);
  pinMode(PIR2, INPUT);
  pinMode(PIR3, INPUT);
  pinMode(PIR4, INPUT);
  pinMode(LED1, OUTPUT);
  pinMode(LED2, OUTPUT);
  pinMode(LED3, OUTPUT);

  // Initialize the variables
  temp = 0.0;
  hum = 0.0;
  pir1 = false;
  pir2 = false;
  pir3 = false;
  pir4 = false;
  ac = false;
  lamp1 = false;
  lamp2 = false;
}

void loop() {
  // Read the temperature and humidity from the DHT22 sensor
  temp = dht.readTemperature();
  hum = dht.readHumidity();

  // Check if the readings are valid
  if (isnan(temp) || isnan(hum)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  // Print the readings to the serial monitor
  Serial.print("Temperature: ");
  Serial.print(temp);
  Serial.print(" *C, Humidity: ");
  Serial.print(hum);
  Serial.println(" %");

  // Display the readings on the LCD display
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(temp);
  lcd.print(" C");
  lcd.setCursor(0, 1);
  lcd.print("Hum: ");
  lcd.print(hum);
  lcd.print(" %");

  // Read the states of the PIR sensors
  pir1 = digitalRead(PIR1);
  pir2 = digitalRead(PIR2);
  pir3 = digitalRead(PIR3);
  pir4 = digitalRead(PIR4);

  // Print the states of the PIR sensors to the serial monitor
  Serial.print("PIR1: ");
  Serial.print(pir1);
  Serial.print(", PIR2: ");
  Serial.print(pir2);
  Serial.print(", PIR3: ");
  Serial.print(pir3);
  Serial.print(", PIR4: ");
  Serial.println(pir4);

  // Control the air conditioner based on the temperature and the PIR sensors
  if (temp > optTemp && (pir1 || pir2 || pir3 || pir4)) {
    // Turn on the air conditioner if the temperature is above the optimum and there is people in the room
    ac = true;
    digitalWrite(LED1, HIGH); // Turn on the LED 1
    Serial.println("Air conditioner is ON");
  } else {
    // Turn off the air conditioner otherwise
    ac = false;
    digitalWrite(LED1, LOW); // Turn off the LED 1
    Serial.println("Air conditioner is OFF");
  }

  // Control the lamps based on the PIR sensors
  if (pir1 || pir2) {
    // Turn on the lamp 1 if there is people in the front row
    lamp1 = true;
    digitalWrite(LED2, HIGH); // Turn on the LED 2
    Serial.println("Lamp 1 is ON");
  } else {
    // Turn off the lamp 1 otherwise
    lamp1 = false;
    digitalWrite(LED2, LOW); // Turn off the LED 2
    Serial.println("Lamp 1 is OFF");
  }

    if (pir3 || pir4) {
    // Turn on the lamp 2 if there is people in the back row
    lamp2 = true;
    digitalWrite(LED3, HIGH); // Turn on the LED 3
    Serial.println("Lamp 2 is ON");
  } else {
    // Turn off the lamp 2 otherwise
    lamp2 = false;
    digitalWrite(LED3, LOW); // Turn off the LED 3
    Serial.println("Lamp 2 is OFF");
  }

  // Delay for a while
  delay(delayTime);
}