#include <LiquidCrystal.h>
#include <Servo.h>

// =======================
// Konfigurasi LCD
// =======================
LiquidCrystal lcd(7, 8, 9, 10, 11, 12);

// =======================
// Konfigurasi Pin
// =======================
const int o2Pin = A0;      // Input sensor O₂ (potensiometer)
const int rpmPin = A1;     // Input simulasi RPM (potensiometer)
const int servoPin = 6;    // Output servo

Servo limiterServo;        // Objek servo

// =======================
// Variabel Global
// =======================
float o2Voltage = 0;
int o2Value = 0;
int rpmValue = 0;
int rpm = 0;
int servoAngle = 0;
String mixtureStatus;

void setup() {
  lcd.begin(16, 2);
  limiterServo.attach(servoPin);

  lcd.print("ECU SIMULATOR");
  lcd.setCursor(0, 1);
  lcd.print("Init System...");
  delay(2000);
  lcd.clear();
}

void loop() {
  // =======================
  // BACA SENSOR O₂
  // =======================
  o2Value = analogRead(o2Pin);
  o2Voltage = o2Value * (5.0 / 1023.0);

  if (o2Voltage < 0.3) mixtureStatus = "LEAN";
  else if (o2Voltage <= 0.7) mixtureStatus = "IDEAL";
  else mixtureStatus = "RICH";

  // =======================
  // BACA PULSER (SIMULASI RPM)
  // =======================
  rpmValue = analogRead(rpmPin);
  rpm = map(rpmValue, 0, 1023, 0, 8000); // Skala 0–8000 RPM

  // =======================
  // KONTROL SERVO
  // =======================
  if (rpm < 1000) servoAngle = 0;
  else if (rpm >= 1000 && rpm <= 5000) {
    // Linear antara 1000 → 45°, 5000 → 90°
    servoAngle = map(rpm, 1000, 5000, 45, 90);
  } 
  else servoAngle = 90;

  limiterServo.write(servoAngle);

  // =======================
  // TAMPILKAN DATA
  // =======================
  lcd.setCursor(0, 0);
  lcd.print("RPM:");
  lcd.print(rpm);
  lcd.print("   "); // hapus sisa karakter lama

  lcd.setCursor(0, 1);
  lcd.print("O2:");
  lcd.print(o2Voltage, 2);
  lcd.print("V ");
  lcd.print(mixtureStatus);
  
  delay(300);
}