// NeoPixel Ring simple sketch (c) 2013 Shae Erisson
// released under the GPLv3 license to match the rest of the AdaFruit NeoPixel library
#include <Adafruit_NeoPixel.h>

#define PIN            10
#define NUMPIXELS      24

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

uint32_t counter;
uint16_t fakeMinutes, fakeHours;
char buffer[6];

void iterate_pixels(uint8_t index)
{
  if (index == 0) {
    pixels.clear();
    pixels.show();
    return;
  }

  for (int i = 0; i < index; i++) {
    pixels.setPixelColor(i, Adafruit_NeoPixel::Color(255, 0, 255));
    pixels.show();
  }
}

void setup() {
  Serial.begin(9600);
  pixels.begin(); // This initializes the NeoPixel library.
}



void loop() {

  snprintf(buffer, sizeof(buffer), "%02d:%02d", fakeHours, fakeMinutes);
  Serial.println(buffer);

  counter++;
  fakeMinutes = counter % 60;
  fakeHours = trunc(counter / 60);

  static int oldNumHalfHour = -1;
  int numHalfHour = fakeHours * 2 + (fakeMinutes > 30);

  if (oldNumHalfHour != numHalfHour) {
    oldNumHalfHour = numHalfHour;
    Serial.print("Contatore mezzore: ");
    Serial.println(numHalfHour);
    iterate_pixels(numHalfHour);
  }


  delay(500);
}