#include <Adafruit_NeoPixel.h>

#define PIN 8
#define WIDTH 16
#define HEIGHT 16
#define NUMPIXELS (WIDTH * HEIGHT)

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

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

  // Executa padrão de teste
  testPattern();
}

// Função para converter coordenadas XY em índice real na matriz zig-zag
int XYtoIndex(int x, int y) {
  if (y % 2 == 0) {
    return y * WIDTH + x;  // linhas pares: esquerda → direita
  } else {
    return y * WIDTH + (WIDTH - 1 - x);  // linhas ímpares: direita → esquerda
  }
}

// Função de teste: percorre cores básicas
void testPattern() {
  // vermelho
  for (int i = 0; i < NUMPIXELS; i++) {
    strip.setPixelColor(i, strip.Color(255, 0, 0));
  }
  strip.show();
  delay(1000);

  // verde
  for (int i = 0; i < NUMPIXELS; i++) {
    strip.setPixelColor(i, strip.Color(0, 255, 0));
  }
  strip.show();
  delay(1000);

  // azul
  for (int i = 0; i < NUMPIXELS; i++) {
    strip.setPixelColor(i, strip.Color(0, 0, 255));
  }
  strip.show();
  delay(1000);

  // branco
  for (int i = 0; i < NUMPIXELS; i++) {
    strip.setPixelColor(i, strip.Color(255, 255, 255));
  }
  strip.show();
  delay(1000);

  // apagar
  strip.clear();
  strip.show();
}

void loop() {
  if (Serial.available()) {
    String frame = Serial.readStringUntil('\n'); // lê quadro completo

    int startIdx = frame.indexOf("<START>");
    int endIdx   = frame.indexOf("<END>");
    if (startIdx == -1 || endIdx == -1) return;

    String data = frame.substring(startIdx + 7, endIdx);

    int pixelIndex = 0;
    char *token = strtok((char*)data.c_str(), ";");
    while (token != NULL && pixelIndex < NUMPIXELS) {
      int r, g, b;
      if (sscanf(token, "%d,%d,%d", &r, &g, &b) == 3) {
        int x = pixelIndex % WIDTH;
        int y = pixelIndex / WIDTH;
        int realIndex = XYtoIndex(x, y);
        strip.setPixelColor(realIndex, strip.Color(r, g, b));
      }
      pixelIndex++;
      token = strtok(NULL, ";");
    }
    strip.show();
  }
}