#include <Keypad.h>


#define PIR_PIN 11
#define BUZZER_PIN 12
#define LED_PIN 13

const byte ROWS = 4; // Number of keypad rows
const byte COLS = 4; // Number of keypad columns

char keys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};

byte rowPins[ROWS] = {9, 8, 7, 6}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {5, 4, 3, 2}; // Connect to the column pinouts of the keypad

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

int alarmState = 0;
char password[5] = "1234"; // Change the password as needed

void setup() {
  pinMode(PIR_PIN, INPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(LED_PIN, OUTPUT);
  digitalWrite(BUZZER_PIN, LOW);
  digitalWrite(LED_PIN, LOW);
  Serial.begin(9600);
}

void loop() {
  if (alarmState == 0) {
    checkPassword(); // Check if password is entered to arm the alarm
  } else {
    checkMotion();   // Check for motion to trigger the alarm
  }
}

void checkPassword() {
  char key = keypad.getKey();
  
  if (key) {
    if (key == password[strlen(password) - 1]) {
      if (strlen(password) == 4) {
        disarmAlarm();
      } else {
        password[strlen(password)] = key;
      }
    } else {
      resetPassword();
    }
  }
}

void disarmAlarm() {
  alarmState = 1;
  digitalWrite(LED_PIN, HIGH);
  delay(500);
  digitalWrite(LED_PIN, LOW);
}

void resetPassword() {
  memset(password, 0, sizeof(password));
}

void checkMotion() {
  int motion = digitalRead(PIR_PIN);
  
  if (motion == HIGH) {
    activateAlarm();
  }
}

void activateAlarm() {
  digitalWrite(BUZZER_PIN, HIGH);
  delay(2000); // Adjust the duration of the alarm as needed
  digitalWrite(BUZZER_PIN, LOW);
}