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

const int POT_PIN = A0;
const int BUTTON_PIN = 2;
const int LED_PIN = 3;
const int BUZZER_PIN = 9;

LiquidCrystal_I2C lcd(0x27, 16, 2);

bool ligado = false;
bool lastButtonState = HIGH;

void setup() {
  pinMode(BUTTON_PIN, INPUT_PULLUP);
  pinMode(LED_PIN, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);

  lcd.init();
  lcd.backlight();

  Serial.begin(115200);
}

void loop() {
  bool currentButton = digitalRead(BUTTON_PIN);

  if (lastButtonState == HIGH && currentButton == LOW) {
    ligado = !ligado;
    delay(50);
  }

  lastButtonState = currentButton;

  int potValue = analogRead(POT_PIN);

  int freq = map(potValue, 0, 1023, 100, 2000);

  if (ligado) {
    tone(BUZZER_PIN, freq);
    digitalWrite(LED_PIN, HIGH);
  } else {
    noTone(BUZZER_PIN);
    digitalWrite(LED_PIN, LOW);
  }

  lcd.setCursor(0, 0);
  lcd.print("Pot: ");
  lcd.print(potValue);
  lcd.print("   ");

  lcd.setCursor(0, 1);
  lcd.print("Freq: ");
  lcd.print(freq);
  lcd.print(" Hz ");

  Serial.print("Pot: ");
  Serial.print(potValue);
  Serial.print(" | Freq: ");
  Serial.println(freq);

  delay(100);
}