Smart Home Security System using Arduino and IoT

#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>
#include <MFRC522.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

const char* ssid = "Your_SSID";
const char* password = "Your_PASSWORD";
ESP8266WebServer server(80);

#define PIR_SENSOR D2
#define BUZZER D3
#define RELAY D4
#define RST_PIN D9
#define SS_PIN D10

MFRC522 mfrc522(SS_PIN, RST_PIN);
LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
    Serial.begin(115200);
    WiFi.begin(ssid, password);
    
    while (WiFi.status() != WL_CONNECTED) {
        delay(1000);
        Serial.println("Connecting to Wi-Fi...");
    }
    
    Serial.println("Connected to Wi-Fi");
    Serial.println(WiFi.localIP());
    
    pinMode(PIR_SENSOR, INPUT);
    pinMode(BUZZER, OUTPUT);
    pinMode(RELAY, OUTPUT);
    digitalWrite(RELAY, HIGH);
    digitalWrite(BUZZER, LOW);
    SPI.begin();
    mfrc522.PCD_Init();
    lcd.begin();
    lcd.backlight();
    lcd.setCursor(0, 0);
    lcd.print("Security System");
    
    server.on("/alert", []() {
        server.send(200, "text/plain", "Intrusion detected!");
    });
    
    server.on("/unlock", []() {
        digitalWrite(RELAY, LOW);
        delay(5000);
        digitalWrite(RELAY, HIGH);
        server.send(200, "text/plain", "Door Unlocked");
    });
    
    server.begin();
    Serial.println("Server started");
}

void loop() {
    server.handleClient();
    
    // PIR Motion Detection
    if (digitalRead(PIR_SENSOR) == HIGH) {
        Serial.println("Motion Detected!");
        lcd.setCursor(0, 1);
        lcd.print("Motion Detected!");
        digitalWrite(BUZZER, HIGH);
        server.send(200, "text/plain", "Intrusion Alert!");
        delay(5000);
        digitalWrite(BUZZER, LOW);
        lcd.setCursor(0, 1);
        lcd.print("                ");
    }
    
    // RFID Authentication
    if (mfrc522.PICC_IsNewCardPresent() && mfrc522.PICC_ReadCardSerial()) {
        String uid = "";
        for (byte i = 0; i < mfrc522.uid.size; i++) {
            uid += String(mfrc522.uid.uidByte[i], HEX);
        }
        Serial.print("Card UID: ");
        Serial.println(uid);
        
        if (uid == "YOUR_CARD_UID") {
            lcd.setCursor(0, 1);
            lcd.print("Access Granted");
            digitalWrite(RELAY, LOW);
            delay(5000);
            digitalWrite(RELAY, HIGH);
        } else {
            lcd.setCursor(0, 1);
            lcd.print("Access Denied");
            digitalWrite(BUZZER, HIGH);
            delay(3000);
            digitalWrite(BUZZER, LOW);
        }
        delay(2000);
        lcd.setCursor(0, 1);
        lcd.print("                ");
    }
}