#include <Adafruit_NeoPixel.h>

#define PIN            8
#define NUMPIXELS      46

Adafruit_NeoPixel pixels = Adafruit_NeoPixel(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);
uint8_t red_colour;
uint8_t green_colour;
uint8_t blue_colour;
int red_color;
int green_color;
int blue_color;

uint8_t hue = 0;
double hue_double = 0;
double inline threeway_max(double a, double b, double c)
{
	return max(a, max(b, c));
}

double inline threeway_min(double a, double b, double c)
{
	return min(a, min(b, c));
}
void RgbToHsv(uint8_t red, uint8_t green, uint8_t blue, double& hue, double& saturation, double& value)
{
	auto rd = static_cast<double>(red) / 255;
	auto gd = static_cast<double>(green) / 255;
	auto bd = static_cast<double>(blue) / 255;
	auto max = threeway_max(rd, gd, bd), min = threeway_min(rd, gd, bd);
	 
	value = max;

	auto d = max - min;
	saturation = max == 0 ? 0 : d / max;

	hue = 0;
	if (max != min)
	{
		if (max == rd)
		{
			hue = (gd - bd) / d + (gd < bd ? 6 : 0);
		}
		else if (max == gd)
		{
			hue = (bd - rd) / d + 2;
		}
		else if (max == bd)
		{
			hue = (rd - gd) / d + 4;
		}
		hue /= 6;
	}
}
void HsvToRgb(double hue, double saturation, double value, uint8_t& red, uint8_t& green, uint8_t& blue)
{
	double r, g, b;

	auto i = static_cast<int>(hue * 6);
	auto f = hue * 6 - i;
	auto p = value * (1 - saturation);
	auto q = value * (1 - f * saturation);
	auto t = value * (1 - (1 - f) * saturation);

	switch (i % 6)
	{
	case 0: r = value , g = t , b = p;
		break;
	case 1: r = q , g = value , b = p;
		break;
	case 2: r = p , g = value , b = t;
		break;
	case 3: r = p , g = q , b = value;
		break;
	case 4: r = t , g = p , b = value;
		break;
	case 5: r = value , g = p , b = q;
		break;
	}

	red = static_cast<uint8_t>(r * 255);
	green = static_cast<uint8_t>(g * 255);
	blue = static_cast<uint8_t>(b * 255);
}


void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pixels.begin();
}

void loop() {
  // put your main code here, to run repeatedly:
  // for (int j = 0; j < 255; j++) {
		for (int i = 0; i < NUMPIXELS; i++) {
			HsvToRgb(hue_double,1,1, red_colour, green_colour, blue_colour);
			red_color = red_colour;
			green_color = green_colour;
			blue_color = blue_colour;      
			pixels.setPixelColor(i,pixels.Color(red_color,green_color,blue_color));
			
  	}
		pixels.show();
		delay(50);
		Serial.println(hue_double);
		hue_double += 0.01;
		if(hue_double > 1){
			hue_double = 0;
		}

}