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

#define DOPPLER_PIN 18
#define RELAY_PIN   19

#define MSG0 "Motion Detected!"
#define MSG1 "No Motion Detected!"

#define INTERVAL 5  // Interval 5 detik

unsigned long previous_millis = 0;    // Menyimpan waktu sebelumnya
unsigned long current_millis;
int8_t count = -2;

int motion_val = 0;
uint8_t is_off = 1;

LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  pinMode(RELAY_PIN, OUTPUT);  
  pinMode(DOPPLER_PIN, INPUT);

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

void loop() {
  current_millis = millis();

  motion_val = digitalRead(DOPPLER_PIN);

  lcd.setCursor(0, 0);

  if (motion_val == HIGH) {
    if (is_off == 0 && count == -2) return;

    digitalWrite(RELAY_PIN, HIGH);

    lcd.clear();
    lcd.print(MSG0);

    is_off = 0;
    count = -2;

    return;
  }

  if (count < -1) {
    count = INTERVAL;
    lcd.print(MSG1);
  }
  
  if (is_off == 1) return;

  // Menunggu 5 detik sebelum mematikan lampu
  if (current_millis - previous_millis >= 1000) {
    previous_millis = current_millis;
    count -= 1;

    lcd.setCursor(0, 1);
    lcd.printf("Delay: %d", count);
    lcd.flush();
  }

  if (count < -1) {
    //count = -1;
    is_off = 1;

    digitalWrite(RELAY_PIN, LOW);

    lcd.clear();
  }
}