#include <avr/io.h>
#include <avr/delay.h>

int maxValue(int x) {
	if (x > 255) {
		return 255;
	}

	return x;
}

int minValue(int x) {
	if (x < 0) {
		return 0;
	}

	return x;
}

int main(void) {
	TCCR0|=(1<<WGM00)|(1<<WGM01)|(1<<COM01)|(0<<CS02)|(0<<CS01)|(1<<CS00);
	TCCR1A|=(1<<COM1A1)|(1<<COM1B1)|(1<<WGM11);
	TCCR1B|=(1<<WGM13)|(1<<WGM12)|(0<<CS12)|(0<<CS11)|(1<<CS10);
	ICR1=255;

	DDRB |= (1 << PB3);
	DDRD |= (1 << PD5) | (1 << PD4);
	DDRA = 0x00; // in

	PORTA = 0xFF;

	int r = 255;
	int g = 255;
	int b = 255;

	OCR0 = r;	// PB3, R
	OCR1A = g;	// PD5, G
	OCR1B = b;	// PD4, B

	int constN = 255 / 7;
	int lastButton = 0;

	while (1) {
		if (PINA == lastButton) {
			continue;
		}

		lastButton = PINA;

		switch (PINA) {
			// R
            case 0b11111110:
            	r += constN;
            	r = maxValue(r);
				OCR0 = r;
                break;
            case 0b11111101:
            	r -= constN;
            	r = minValue(r);
				OCR0 = r;
                break;

            // G
            case 0b11111011:
            	g += constN;
            	g = maxValue(g);
				OCR1A = g;
                break;
            case 0b11110111:
            	g -= constN;
            	g = minValue(g);
				OCR1A = g;
                break;

            // B
            case 0b11101111:
            	b += constN;
            	b = maxValue(b);
				OCR1B = b;
                break;
            case 0b11011111:
            	b -= constN;
            	b = minValue(b);
				OCR1B = b;
                break;
		}
	}

	return 0;
}