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

#define PIN        0
#define NUMPIXELS  7

typedef struct struct_message {
  int brushSize;
  uint32_t color;  // Direct decimal color like 16777215
} struct_message;

struct_message ledData;

int lastBrushSize = -1;
int brush = 0;

Adafruit_NeoPixel pixels(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);

// Callback when data is received
void OnDataRecv(const esp_now_recv_info_t *recvInfo, const uint8_t *incomingData, int len) {
  memcpy(&ledData, incomingData, sizeof(ledData));
  
  Serial.print("📥 Brush Size: ");
  Serial.println(ledData.brushSize);
  Serial.print("🎨 Decimal Color: ");
  Serial.println(ledData.color);
}

void setup() {
  Serial.begin(115200);
  WiFi.mode(WIFI_STA);

  Serial.print("Receiver MAC Address: ");
  Serial.println(WiFi.macAddress());

  if (esp_now_init() != ESP_OK) {
    Serial.println("❌ Error initializing ESP-NOW");
    return;
  }

  esp_now_register_recv_cb(OnDataRecv);

  pixels.begin();
  pixels.clear();
  pixels.show();
}

void loop() {
  if (ledData.brushSize != lastBrushSize || brush > 0) {
    lastBrushSize = ledData.brushSize;
    
    switch (ledData.brushSize) {
      case 1: brush = 1; break;
      case 2: brush = 4; break;
      case 3: brush = 7; break;
      default: brush = 0; break;
    }

    pixels.clear();

    if (ledData.brushSize == 1) {
      pixels.setPixelColor(0, ledData.color);

    } else if (ledData.brushSize == 2) {
      pixels.setPixelColor(0, ledData.color);
      pixels.setPixelColor(1, ledData.color);
      pixels.setPixelColor(4, ledData.color);
      pixels.setPixelColor(5, ledData.color);

    } else if (ledData.brushSize == 3) {
      for (int i = 0; i < NUMPIXELS; i++) {
        pixels.setPixelColor(i, ledData.color);
      }
    }
    
    pixels.show();

    Serial.print("✨ Lighting up ");
    Serial.print(brush);
    Serial.println(" pixels.");
  }
}