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

// LCD (endereço comum: 0x27 ou 0x3F)
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Pinos
Const int TRIG 5
Const int ECHO 18
Const int BUZZER 19
Const int LED 2
Const int PIR 26

LiquidCrystal_I2C lcd(0x27, 16, 2); 


void setup() {
  pinMode(TRIG, OUTPUT);
  pinMode(ECHO, INPUT);
  pinMode(BUZZER, OUTPUT);
  pinMode(LED, OUTPUT);
  pinMode(PIR, INPUT);
  
  
  lcd.init();
  lcd.backlight();
  lcd.print("Sistema ligado"); 
  serial.begin(115200); 

  long lerDistancia() {

  digitalWrite(TRIG, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG, LOW);
  return pulseIn(echo, HIGH) * 0.034 / 2; 
  }

void gerenciarBuzzer(long distancia) {
if (distancia < 20) [
tone (buzzer, 1000); 
] else if (distancia < 100) {
tone(buzzer 1000, 100 ); 
delay (distancia * 5); 
} else{ (buzzer);

}
}

void loop ()

if (digitalRead(PIR)) {
long dist


}

}
  Serial.begin(115200);


void loop() {

  digitalWrite(TRIG, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG, LOW);

  // Lê retorno
  duracao = pulseIn(ECHO, HIGH);

  // Calcula distância (cm)
  distancia = duracao * 0.034 / 2;

  // Mostra no LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Distancia:");
  lcd.setCursor(0, 1);
  lcd.print(distancia);

  Serial.println(distancia);

  // Controle buzzer e LED
  if (distancia < 20) {
    digitalWrite(BUZZER, HIGH);
    digitalWrite(LED, HIGH);
  } else {
    digitalWrite(BUZZER, LOW);
    digitalWrite(LED, LOW);
  }

  delay(500);
}