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

#define BUTTON_PIN D8

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

typedef struct struct_message {
  int track;
} struct_message;

struct_message msg;

bool lastState = HIGH;
int currentTrack = 1;

void setup() {
  Serial.begin(115200);
  pinMode(BUTTON_PIN, INPUT_PULLUP);

  WiFi.mode(WIFI_STA);

  if (esp_now_init() != ESP_OK) {
    Serial.println("ESP-NOW init failed");
    return;
  }

  esp_now_peer_info_t peerInfo = {};
  memcpy(peerInfo.peer_addr, peerAddress, 6);
  peerInfo.channel = 0;
  peerInfo.encrypt = false;

  esp_now_add_peer(&peerInfo);

  Serial.println("Sender ready");
}

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

  // detect press
  if (lastState == HIGH && currentState == LOW) {

    msg.track = currentTrack;

    Serial.print("Sending track: ");
    Serial.println(currentTrack);

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

    // move to next track
    currentTrack++;
    if (currentTrack > 4) currentTrack = 1;

    delay(300); // debounce
  }

  lastState = currentState;
}