#include <Arduino.h>
#include "ws2812b.h"

// Platform constants
const uint16_t MAX_RESOLUTION = 120;

// Pixel formats — both exist, only GRB is used.
struct RGBPixelFormat {
    uint8_t r, g, b;
};

struct GRBPixelFormat {
    uint8_t g, r, b;
};

class Strip {
public:
    static const uint8_t DATA_PIN = 2;

    GRBPixelFormat pixels[MAX_RESOLUTION];
    uint16_t length;

    Strip(uint16_t length) {
        this->length = length;
        memset(pixels, 0, sizeof(pixels));
    }

    void update() {
        ws2812b_write(DATA_PIN, (uint8_t*)pixels, length * sizeof(GRBPixelFormat));
    }
};

Strip strip(20);

void setup() {
    pinMode(Strip::DATA_PIN, OUTPUT);

    for (uint16_t i = 0; i < strip.length; i++) {
        uint8_t phase = i % 3;
        if (phase == 0) {
            strip.pixels[i].r = 200;
            strip.pixels[i].g = 0;
            strip.pixels[i].b = 0;
        } else if (phase == 1) {
            strip.pixels[i].r = 0;
            strip.pixels[i].g = 155;
            strip.pixels[i].b = 0;
        } else {
            strip.pixels[i].r = 0;
            strip.pixels[i].g = 0;
            strip.pixels[i].b = 255;
        }
    }

    strip.update();
}

void loop() {
    // static display
}