#include <DHT.h>      
#include <LiquidCrystal.h>  

#define DHTPIN 11            // DHT sensor pin
#define DHTTYPE DHT22        // DHT type (DHT22)

DHT dht(DHTPIN, DHTTYPE);    

const int rs = 2, en = 3, d4 = 4, d5 = 5, d6 = 6, d7 = 7;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);

int ledPin = 13;             // LED pin
int buzzerPin = 10;          // Buzzer pin
int inputPin = 8;            // PIR sensor pin
int pirState = LOW;          // We start, assuming no motion detected
int val = 0;                 // Variable for PIR sensor value
float t;                     // Temperature variable
float h;                     // Humidity variable

void setup() {
    Serial.begin(9600);
    dht.begin();
    lcd.begin(16, 2);
    lcd.setCursor(0, 0);
    lcd.print("    Welcome to  ");
    lcd.setCursor(0, 1);
    lcd.print("  Smart Temp Sens");
    delay(2000);
    lcd.clear();
    pinMode(ledPin, OUTPUT);      // Declare LED as output
    pinMode(buzzerPin, OUTPUT);   // Declare buzzer as output
    pinMode(inputPin, INPUT);     // Declare PIR sensor as input
}

void loop() {
    val = digitalRead(inputPin);  // Read PIR sensor input
    if (val == HIGH) {            // Check if the input is HIGH
        digitalWrite(ledPin, HIGH);  // Turn LED ON
        digitalWrite(buzzerPin, HIGH);  // Turn buzzer ON
        delay(1000);  // Buzzer sound duration
        digitalWrite(buzzerPin, LOW);   // Turn buzzer OFF
        
        if (pirState == LOW) {
            // We have just turned on
                lcd.setCursor(0, 0);
                lcd.print("    Motion detected!");
                lcd.setCursor(0, 1);
                lcd.print("  Temp sens active.");
            Serial.println("Motion detected! Temp sensor active.");
            delay(3000);
            lcd.clear();
            lcd.setCursor(0,3);
            lcd.print("  Temp sensor active.");
            temp_sensor();  // Call the temperature and humidity sensor function
            pirState = HIGH;
        }
    } else {
        digitalWrite(ledPin, LOW);  // Turn LED OFF
        if (pirState == HIGH) {
            // We have just turned off
            Serial.println("Motion ended!");
            // We only want to print on the output change, not state
            pirState = LOW;
        }
    }
}

void temp_sensor() {
    h = dht.readHumidity();
    t = dht.readTemperature();
    
    // Display temperature in Celsius
    lcd.setCursor(0, 0);
    lcd.print("Temp: ");
    lcd.print(t);
    lcd.print((char)223);  // Degree symbol
    lcd.print("C");
    
    // Display humidity
    lcd.setCursor(0, 1);
    lcd.print("Humid: ");
    lcd.print(h);
    lcd.print("% ");
    
    delay(5000);
    
    // Display temperature in Fahrenheit
    lcd.setCursor(0, 0);
    lcd.print("Temp: ");
    lcd.print(dht.convertCtoF(t));
    lcd.print(" ");
    lcd.print((char)223);  // Degree symbol
    lcd.print("F");
    
    delay(5000);
}