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

const int potPin = A0;
const int greenLed = 9;
const int yellowLed = 10;
const int redLed = 11;
const int buzzerPin = 8;

const float voltage = 5.0;
const float lowCurrent = 0.01;
const float highCurrent = 0.02;

LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  pinMode(greenLed, OUTPUT);
  pinMode(yellowLed, OUTPUT);
  pinMode(redLed, OUTPUT);
  pinMode(buzzerPin, OUTPUT);

  lcd.begin(16, 2);
  lcd.backlight();

  lcd.setCursor(0, 0);
  lcd.print("Ohm Meter By SCB");
  delay(2000);
  lcd.clear();
}

void loop() {
  int potValue = analogRead(potPin);
  float resistance = (voltage / (potValue / 1023.0));
  float current = voltage / resistance;

  lcd.setCursor(0, 0);
  lcd.print("Resistansi: ");
  lcd.print(resistance, 1);
  lcd.print(" Ohm   ");

  digitalWrite(greenLed, LOW);
  digitalWrite(yellowLed, LOW);
  digitalWrite(redLed, LOW);
  digitalWrite(buzzerPin, LOW);

  lcd.setCursor(0, 1);
  if (current <= lowCurrent) {
    digitalWrite(greenLed, HIGH);
    lcd.print("Status: Aman     ");
  } else if (current <= highCurrent) {
    digitalWrite(yellowLed, HIGH);
    lcd.print("Status: Waspada  ");
  } else {
    digitalWrite(redLed, HIGH);
    digitalWrite(buzzerPin, HIGH);
    lcd.print("Status: Bahaya   ");
  }
// Cetak arus dalam mA untuk debugging

  delay(500);
}