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

LiquidCrystal_I2C lcd(0x27, 16, 2);

const int trigPins[4] = {9, 5, 7, 11};
const int echoPins[4] = {8, 4, 6, 10};
const int greenLEDs[4] = {2, 3, 12, 13};
const int redLEDs[4] = {A0, A1, A2, A3};

long duration;
int distance[4];

void setup() {
  lcd.begin(16, 2);
  lcd.backlight();

  for (int i = 0; i < 4; i++) {
    pinMode(echoPins[i], INPUT);
    pinMode(trigPins[i], OUTPUT);
    pinMode(greenLEDs[i], OUTPUT);
    pinMode(redLEDs[i], OUTPUT);

    // Inicializa e testa os LEDs
    digitalWrite(greenLEDs[i], HIGH);
    digitalWrite(redLEDs[i], HIGH);
    delay(500);
    digitalWrite(greenLEDs[i], LOW);
    digitalWrite(redLEDs[i], LOW);
  }

  lcd.setCursor(1, 0);
  lcd.print("Estacionamento");
  delay(2000);
  lcd.clear();
}

void loop() {
  for (int i = 0; i < 4; i++) {
    digitalWrite(trigPins[i], HIGH);
    delayMicroseconds(10);
    digitalWrite(trigPins[i], LOW);

    duration = pulseIn(echoPins[i], HIGH);
    distance[i] = duration * 0.034 / 2;
  }

  for (int i = 0; i < 4; i++) {
    if (distance[i] < 15) {
      digitalWrite(greenLEDs[i], LOW);
      digitalWrite(redLEDs[i], HIGH);
    } else {
      digitalWrite(greenLEDs[i], HIGH);
      digitalWrite(redLEDs[i], LOW);
    }
  }

  lcd.setCursor(2, 0);
  lcd.print("1  2  3  4");

  for (int i = 0; i < 4; i++) {
    lcd.setCursor(2 + i * 3, 1);
    if (distance[i] < 15) {
      lcd.print("X"); // X = Ocupado
    } else {
      lcd.print(" "); // (void) = Livre
    }
  }

  delay(1000);
}