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

LiquidCrystal_I2C lcd(0x27, 16, 2);
Servo myServo;

// Pin
const int trigPin = 9;
const int echoPin = 10;
const int ledMerah = 8;
const int ledHijau = 7;

// Variabel
long duration;
int distance;
bool pintuTerbuka = false;  // status pintu

void setup() {
  pinMode(trigPin, OUTPUT);
    pinMode(echoPin, INPUT);
      pinMode(ledMerah, OUTPUT);
        pinMode(ledHijau, OUTPUT);

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

              myServo.attach(6);

                // Kondisi awal
                  digitalWrite(ledMerah, HIGH);
                    digitalWrite(ledHijau, LOW);
                      myServo.write(0);
                        lcd.setCursor(0, 0);
                          lcd.print("Pintu Tertutup");
                          }

                          void loop() {
                            // Hitung jarak
                              digitalWrite(trigPin, LOW);
                                delayMicroseconds(2);
                                  digitalWrite(trigPin, HIGH);
                                    delayMicroseconds(10);
                                      digitalWrite(trigPin, LOW);
                                        duration = pulseIn(echoPin, HIGH);
                                          distance = duration * 0.034 / 2;

                                            // Logika buka pintu
                                              if (distance <= 50 && !pintuTerbuka) {
                                                  pintuTerbuka = true; // ubah status
                                                      digitalWrite(ledMerah, LOW);
                                                          digitalWrite(ledHijau, HIGH);
                                                              myServo.write(90);

                                                                  lcd.clear();
                                                                      lcd.setCursor(0, 0);
                                                                          lcd.print("Pintu Terbuka");
                                                                              delay(10000); // tunggu 10 detik

                                                                                  // Tutup pintu
                                                                                      digitalWrite(ledHijau, LOW);
                                                                                          digitalWrite(ledMerah, HIGH);
                                                                                              myServo.write(0);
                                                                                                  lcd.clear();
                                                                                                      lcd.setCursor(0, 0);
                                                                                                          lcd.print("Pintu Tertutup");

                                                                                                              // Tunggu sampai objek menjauh dulu
                                                                                                                  while (true) {
                                                                                                                        // Baca ulang jarak
                                                                                                                              digitalWrite(trigPin, LOW);
                                                                                                                                    delayMicroseconds(2);
                                                                                                                                          digitalWrite(trigPin, HIGH);
                                                                                                                                                delayMicroseconds(10);
                                                                                                                                                      digitalWrite(trigPin, LOW);
                                                                                                                                                            duration = pulseIn(echoPin, HIGH);
                                                                                                                                                                  distance = duration * 0.034 / 2;

                                                                                                                                                                        if (distance > 50) {
                                                                                                                                                                                pintuTerbuka = false; // reset status agar bisa buka lagi nanti
                                                                                                                                                                                        break; // keluar dari loop tunggu
                                                                                                                                                                                              }
                                                                                                                                                                                                    delay(200);
                                                                                                                                                                                                        }
                                                                                                                                                                                                          }

                                                                                                                                                                                                            delay(300);
                                                                                                                                                                                                            }