#include <WiFi.h>
#include <esp_now.h>

#define BUTTON_PIN D8
#define LED_PIN D2

uint8_t peerAddress[] = {0x7C, 0x2C, 0x67, 0x64, 0xBA, 0xF8};

int trigger = 1;
bool lastState = HIGH;

// RECEIVE (ACK)
void OnDataRecv(const esp_now_recv_info_t *info,
                const uint8_t *incomingData,
                int len) {

  Serial.println("ACK received → blink LED");

  // Blink LED for few seconds
  for (int i = 0; i < 6; i++) {
    digitalWrite(LED_PIN, HIGH);
    delay(300);
    digitalWrite(LED_PIN, LOW);
    delay(300);
  }
}

void setup() {
  Serial.begin(115200);

  pinMode(BUTTON_PIN, INPUT_PULLUP);
  pinMode(LED_PIN, OUTPUT);

  WiFi.mode(WIFI_STA);
  esp_now_init();

  esp_now_peer_info_t peerInfo = {};
  memcpy(peerInfo.peer_addr, peerAddress, 6);
  esp_now_add_peer(&peerInfo);

  esp_now_register_recv_cb(OnDataRecv);

  Serial.println("Board 1 ready");
}

void loop() {
  bool currentState = digitalRead(BUTTON_PIN);

  if (lastState == HIGH && currentState == LOW) {

    Serial.println("Sending trigger");

    esp_now_send(peerAddress, (uint8_t *)&trigger, sizeof(trigger));

    delay(300); // debounce
  }

  lastState = currentState;
}