#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);

//define pin
int pirSensPin = 2;
int ldrSensPin = A0;
int pirState = 0;
int ldrVal = 0;
int ledPin = 3;
int ledPinLDR = 4;
int ledPinPIR = 7;
bool stateLamp = false;

void setup() {
  //inisialisasi
  Serial.begin(9600);
  pinMode(pirSensPin, INPUT);
  pinMode(ldrSensPin, INPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(ledPinLDR, OUTPUT);
  pinMode(ledPinPIR, OUTPUT);

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

//fungsi nyalakan lampu
void NyalakanLampu()
{
  stateLamp = true;
  digitalWrite(ledPin, HIGH);
}

//fungsi matikan lampu
void MatikanLampu()
{
  stateLamp = false;
  digitalWrite(ledPin, LOW);
}

unsigned long terakhirAktif = 0;
const unsigned long jedaMati = 5000;

void loop() {
  // put your main code here, to run repeatedly:
  pirState = digitalRead(pirSensPin); //baca sensor PIR
  ldrVal = analogRead(ldrSensPin); //baca sensor LDR
  bool malam = ldrVal > 500; //cek apakah malam
  digitalWrite(ledPinLDR, malam ? HIGH : LOW); //indikator sensor PIR
  digitalWrite(ledPinPIR, pirState == HIGH ? HIGH : LOW); //indikator sensor LDR

  // LCD
  lcd.setCursor(0,0);
  lcd.print("Cahaya: ");
  lcd.setCursor(8,0);
  lcd.print(ldrVal); //cetak intensitas cahaya
  lcd.print(" CDL");

  lcd.setCursor(0,1);
  lcd.print("Gerak?  ");
  lcd.setCursor(9,1);
  lcd.print(pirState == HIGH ? "YA     " : "TIDAK"); //cetak kondisi gerak

  bool kondisiOn = (pirState == HIGH) || malam;

  if (kondisiOn) { //cek kondisi
    if (!stateLamp) {   //apakah lampu tidak nyala
      NyalakanLampu(); // nyalakan jika sebelumnya mati
    }
    terakhirAktif = millis(); // reset timer
  }
  else {
    if (stateLamp) { //apakah lampu nyala
      if (millis() - terakhirAktif >= jedaMati) {//apakah waktu melwati batas
        MatikanLampu(); //matikan lampu setelah 5 detik
      }
    }
  }
}