// 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>

// Which pin on the Arduino is connected to the NeoPixels?
#define PIN        9 // On Trinket or Gemma, suggest changing this to 1

// How many NeoPixels are attached to the Arduino?
#define NUMPIXELS 40 // Popular NeoPixel ring size

// When setting up the NeoPixel library, we tell it how many pixels,
// and which pin to use to send signals. Note that for older NeoPixel
// strips you might need to change the third parameter -- see the
// strandtest example for more information on possible values.
Adafruit_NeoPixel pixels(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);

#define DELAYVAL 50 // Time (in milliseconds) to pause between pixels

#define BARLENGTH 10 // Length of moving bar

bool isFirstBarLength = 1; // whether first creating bar
int pixelIdx = 0;
int background[3] = {0, 0, 0};
int r = 16;
int g = 10;
int b = 10;

void setup() {
  pixels.begin(); // INITIALIZE NeoPixel strip object (REQUIRED)
}

void loop() {

  // The first NeoPixel in a strand is #0, second is 1, all the way up
  // to the count of pixels minus one.
  // for(int i=0; i<NUMPIXELS; i++) { // For each pixel...

  //   // pixels.Color() takes RGB values, from 0,0,0 up to 255,255,255:
  //   pixels.setPixelColor(i, pixels.Color(200, 200, 200));

  //   pixels.show();   // Send the updated pixel colors to the hardware.

  //   delay(DELAYVAL); // Pause before next pass through loop
  // }

  if (isFirstBarLength) {
    pixels.clear();
    for (int i = 0; i < BARLENGTH; i++) {
      pixels.setPixelColor(i, pixels.Color(r, g, b));
      pixels.show();
      pixelIdx++;
      delay(DELAYVAL);
    }
    isFirstBarLength = 0;
  }

  bool powerOn = 1;

  while (powerOn) {
    pixels.setPixelColor(pixelIdx, pixels.Color(r, g, b));
    pixels.show();

    pixels.setPixelColor((pixelIdx - BARLENGTH), pixels.Color(background[0], background[1], background[2]));
    pixels.show();

    if (pixelIdx >= NUMPIXELS) {
      pixels.setPixelColor(pixelIdx - NUMPIXELS, pixels.Color(r, g, b));
      pixels.show();

      if (pixelIdx >= (NUMPIXELS - 1) + BARLENGTH) {
        powerOn = 0;
        pixelIdx = BARLENGTH - 1;
      }
    }

    pixelIdx++;

    if (r > 10 && r < 160 && g == 10 && b == 10) {
      r += 2;
    }
    if (r >= 160) {
      r = 10;
      g = 16;
    }
    if (g > 10 && g < 160 && r == 10 && b == 10) {
      g += 2;
    }
    if (g >= 160) {
      g = 10;
      b = 16;
    }
    if (b > 10 && b < 160 && r == 10 && g == 10) {
      b += 2;
    }
    if (b >= 160) {
      b = 10;
      r = 16;
    }

    delay(DELAYVAL);
  }
}