// Generic esp32 core does not define LED_BUILTIN; DevKit status output is GPIO 2.
const int LED_BUILTIN = 2;

// Add filtering to reduce false triggers
const int PIR_PIN = 13;
const int MIN_TRIGGER_DURATION = 500; // Milliseconds
unsigned long triggerStartTime = 0;
bool confirmedMotion = false;

void setup() {
  Serial.begin(115200);
  Serial.println("PIR warm-up: wait 60 seconds");
  pinMode(PIR_PIN, INPUT);
  pinMode(LED_BUILTIN, OUTPUT);
  delay(60000);  // Wait for PIR warm-up
}

void loop() {
  int pirState = digitalRead(PIR_PIN);

  if (pirState == HIGH) {
    if (triggerStartTime == 0) {
      triggerStartTime = millis(); // Start timing
    } else if (millis() - triggerStartTime > MIN_TRIGGER_DURATION) {
      // Confirmed motion only if PIR stays HIGH for 500ms
      if (!confirmedMotion) {
        confirmedMotion = true;
        Serial.println("CONFIRMED MOTION");
        digitalWrite(LED_BUILTIN, HIGH);
      }
    }
  } else {
    // PIR went LOW - reset
    triggerStartTime = 0;
    confirmedMotion = false;
    digitalWrite(LED_BUILTIN, LOW);
  }

  delay(50);
}