// --- DEFINISI PIN ---
#define SWITCH_PIN     PA0
#define IR_SENSOR_PIN  PA1

#define LED_GREEN      PB0
#define LED_RED        PB1
#define BUZZER         PB2

// --- VARIABEL TIMER ---
unsigned long startTime = 0;
bool detecting = false;

void setup() {
  // Input
  pinMode(SWITCH_PIN, INPUT);      // pakai pull eksternal
  pinMode(IR_SENSOR_PIN, INPUT);   // pakai pull-down eksternal

  // Output
  pinMode(LED_GREEN, OUTPUT);
  pinMode(LED_RED, OUTPUT);
  pinMode(BUZZER, OUTPUT);

  // Default OFF
  digitalWrite(LED_GREEN, LOW);
  digitalWrite(LED_RED, LOW);
  digitalWrite(BUZZER, LOW);
}

void loop() {

  // === 1. CEK SWITCH ===
  // Switch aktif saat HIGH (sesuai referensi kode Anda)
  if (digitalRead(SWITCH_PIN) == HIGH) {

    // === 2. CEK IR SENSOR ===
    // LOW = mendeteksi benda
    if (digitalRead(IR_SENSOR_PIN) == LOW) {

      // Jika baru mulai deteksi
      if (!detecting) {
        detecting = true;
        startTime = millis();
      }

      // Hitung durasi deteksi
      if (millis() - startTime >= 15000) {
        // === KONDISI ALARM ===
        digitalWrite(LED_RED, HIGH);
        digitalWrite(LED_GREEN, LOW);
        digitalWrite(BUZZER, HIGH);
      }

    } else {
      // === TIDAK MENDETEKSI ===
      detecting = false;

      digitalWrite(LED_RED, LOW);
      digitalWrite(LED_GREEN, HIGH);
      digitalWrite(BUZZER, LOW);
    }

  } else {
    // === SWITCH OFF ===
    detecting = false;

    digitalWrite(LED_GREEN, LOW);
    digitalWrite(LED_RED, LOW);
    digitalWrite(BUZZER, LOW);
  }

  delay(10); // ringan, tidak mengganggu timing utama
}