#include <LiquidCrystal_I2C.h>
#include <Servo.h>
#include "HX711.h"

// Pin configuration
const int trigPin = PA8;
const int echoPin = PA9;
const int buzzerPin = PA2;
const int relayPin = PA3;
const int servoPin = PA4;
const int proximityPin = PA5; // digunakan sebagai sensor logam (aktif: HIGH)

// Load cell pins
#define DT PA6
#define SCK PA7

HX711 scale;
Servo myServo;
LiquidCrystal_I2C lcd(0x27, 16, 2);

long duration;
int distance;
float weight;

void setup() {
  Serial.begin(9600);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(buzzerPin, OUTPUT);
  pinMode(relayPin, OUTPUT);
  pinMode(proximityPin, INPUT);

  myServo.attach(servoPin);
  myServo.write(90); // posisi awal (tidak menggeser)

  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("Botol Checker");
  lcd.setCursor(0, 1);
  lcd.print("Inisialisasi...");

  scale.begin(DT, SCK);
  delay(2000);
  scale.set_scale(); 
  scale.tare();       // mengatur 0
  lcd.clear();
}

void loop() {
  distance = getDistance();

  if (distance < 10) { // botol terdeteksi masuk
    digitalWrite(relayPin, HIGH); // aktifkan conveyor
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Botol Terdeteksi");

    delay(1000); // waktu botol menuju load cell
    digitalWrite(relayPin, LOW); // stop conveyor
    delay(1000); // waktu botol diam di atas load cell

    weight = scale.get_units(5);
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Berat: ");
    lcd.print(weight);
    lcd.print(" g");

    if (weight < 100 || weight > 200) {
      lcd.setCursor(0, 1);
      lcd.print("Berat Salah!");
      myServo.write(0); // geser ke jalur reject
      delay(2000);
      myServo.write(90); // kembali ke posisi awal
    } else {
      lcd.setCursor(0, 1);
      lcd.print("Berat Sesuai");
    }

    delay(1500);

    // Cek material
    int metalDetected = digitalRead(proximityPin);
    if (metalDetected == HIGH) {
      digitalWrite(buzzerPin, HIGH);
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Material: Logam");
    } else {
      digitalWrite(buzzerPin, LOW);
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Material: NonLogam");
    }

    lcd.setCursor(0, 1);
    lcd.print("Sortir selesai");
    delay(3000);
    lcd.clear();
  }

  delay(200);
}

int getDistance() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  return duration * 0.034 / 2;
}