#include <ESP32Servo.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

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

// Servo setup
Servo myServo;

// Pins
int pirPin = 23;      // PIR sensor output
int relayPin = 19;    // Relay control
int servoPin = 18;    // Servo motor
int pirState = LOW;

void setup() {
  Serial.begin(115200);

  // PIR, Relay
  pinMode(pirPin, INPUT);
  pinMode(relayPin, OUTPUT);

  // Servo setup (with pulse width range for SG90)
  myServo.attach(servoPin, 500, 2400);

  // LCD setup
  lcd.init();
  lcd.backlight();

  // Initial state
  myServo.write(0);            // Door unlocked
  digitalWrite(relayPin, LOW); // Alarm OFF
  lcd.setCursor(0, 0);
  lcd.print("System Ready");
}

void loop() {
  int motion = digitalRead(pirPin);

  if (motion == HIGH && pirState == LOW) {
    Serial.println("Motion Detected! Door Locked & Alarm ON");
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Motion Detected!");
    lcd.setCursor(0, 1);
    lcd.print("Door Locked");

    myServo.write(90);         // Lock door
    digitalWrite(relayPin, HIGH); // Alarm ON

    pirState = HIGH;
    delay(3000); // Keep locked for 3s
  }
  else if (motion == LOW && pirState == HIGH) {
    Serial.println("No Motion. Door Unlocked & Alarm OFF");
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("No Motion");
    lcd.setCursor(0, 1);
    lcd.print("Door Unlocked");

    myServo.write(0);          // Unlock door
    digitalWrite(relayPin, LOW); // Alarm OFF

    pirState = LOW;
  }
}