#ifndef FADER_H
#define FADER_H

#include "ESP8266lib/ext/led/WS2812B.h"

/** fade between two colors */
class FadeBetween {

	Color c1;
	Color c2;
	int pos;
	int speed;
	int dir;

public:

	/** ctor */
	FadeBetween() {
        restart();
	}

	void setColor1(Color c1) {
		this->c1 = c1;
	}

	void setColor2(Color c2) {
		this->c2 = c2;
	}

    void restart()  {
        pos = 0;
        speed = 64;
        dir = 0;
    }

	void update() {

		if (dir == 0) {
			++pos;
			if (pos == speed) {dir = 1;}
		} else {
			--pos;
			if (pos == 0) {dir = 0;}
		}

	}

	Color getCurrent() const {
		const int fac0 = pos;
		const int fac1 = speed - fac0;
		Color c;
        c.r = clamp( (c1.r * fac0 + c2.r * fac1) / speed );
        c.g = clamp( (c1.g * fac0 + c2.g * fac1) / speed );
        c.b = clamp( (c1.b * fac0 + c2.b * fac1) / speed );
		return c;
	}

private:

    static inline uint8_t clamp(int val) {
        if (val > 255) {return 255;}
        if (val < 0) {return 0;}
        return val;
    }

};

#endif // FADER_H