#include "Adafruit_Keypad.h"
#include <LiquidCrystal_I2C.h>

// Initialize LCD with I2C address 0x27, 16 columns, and 2 rows
LiquidCrystal_I2C lcd(0x27, 16, 2);

const byte ROWS = 4;
const byte COLS = 4;

int led = 12;  // LED connected to pin 1
int buz = 13;  // Buzzer connected to pin 0

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

// Define row and column pins
byte rowPins[ROWS] = {5, 4, 3, 2};  
byte colPins[COLS] = {11, 10, 9, 8};

// Initialize keypad
Adafruit_Keypad customKeypad = Adafruit_Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

void setup() {
  Serial.begin(9600);  
  customKeypad.begin();
  
  lcd.init();  
  lcd.backlight();  
  lcd.setCursor(0, 0);
  lcd.print("Press a key:");

  pinMode(led, OUTPUT);
  pinMode(buz, OUTPUT);
}

void loop() {
  customKeypad.tick();

  while (customKeypad.available()) {
    keypadEvent e = customKeypad.read();
    
    if (e.bit.EVENT == KEY_JUST_PRESSED) {
      char key = (char)e.bit.KEY;
      Serial.print("Key Pressed: ");
      Serial.println(key);

      // Display the key on the LCD
      lcd.setCursor(0, 1);
      lcd.print("Key: ");
      lcd.print(key);
      lcd.print("   "); // Clear extra characters

      // Key "1" → Blink LED 3 times
      if (key == '1') {
        for (int i = 0; i < 3; i++) {
          digitalWrite(led, HIGH);
          delay(100);
          digitalWrite(led, LOW);
          delay(100);
        }
      }

      // Key "2" → Buzzer sound at 1200Hz for 200ms, off for 200ms
      else if (key == '2') {
        tone(buz, 1200);  // Play tone at 1200Hz
        delay(200);
        noTone(buz);       // Stop tone
        delay(200);
      }
    }
  }
  delay(10);
}