#include <avr/io.h>
#include <avr/signal.h>
#include <avr/interrupt.h>

/* IMPORTANT NOTE: Your PWM generation should be based off COLOR_SPACE_MAX 
   as all RGB values will range from 0 to COLOR_SPACE_MAX */

#define COLOR_SPACE_MAX 255		// Is the range of values the calculations will produce 0 to COLOR_SPACE MAX
#define COLOR_SPACE_CONSTANT (COLOR_SPACE_MAX/6 + 1)

/* Add additional global variable declarations. Remember to use volatile as needed */


int	main(void)
{
	// store the calculated values from H & S 
	unsigned char calc_red = COLOR_SPACE_MAX;
	unsigned char calc_green = COLOR_SPACE_MAX;
	unsigned char calc_blue = COLOR_SPACE_MAX;
	
	/* code initialization */

	sei();
	for(;;)
	{
		// calculate color
		if ( saturation_value_y == 0 ) {
			calc_red = COLOR_SPACE_MAX;                      
			calc_green = COLOR_SPACE_MAX;
			calc_blue = COLOR_SPACE_MAX;
		} else {
			// itermediate values used in calculation
			unsigned char tmp, tmp_r, tmp_1, tmp_2, tmp_3;
			unsigned long tmp_adj;

			tmp = hue_value_x / COLOR_SPACE_CONSTANT;
			tmp_r = hue_value_x - (tmp* COLOR_SPACE_CONSTANT); 
			tmp_1 = ( COLOR_SPACE_MAX * (COLOR_SPACE_MAX - (long)saturation_value_y ) ) / COLOR_SPACE_MAX;
			tmp_adj = (saturation_value_y * tmp_r) /  COLOR_SPACE_CONSTANT;
			tmp_2 = ( COLOR_SPACE_MAX * (COLOR_SPACE_MAX - tmp_adj) ) / COLOR_SPACE_MAX;
			tmp_adj = (saturation_value_y * ( COLOR_SPACE_CONSTANT - tmp_r)) /  COLOR_SPACE_CONSTANT; 
			tmp_3 = ( COLOR_SPACE_MAX * (COLOR_SPACE_MAX - tmp_adj) ) / COLOR_SPACE_MAX;

			if      ( tmp == 0 ) { calc_red = COLOR_SPACE_MAX     ; calc_green = tmp_3 ; calc_blue = tmp_1; }
			else if ( tmp == 1 ) { calc_red = tmp_2	; calc_green = COLOR_SPACE_MAX     ; calc_blue = tmp_1; }
			else if ( tmp == 2 ) { calc_red = tmp_1	; calc_green = COLOR_SPACE_MAX     ; calc_blue = tmp_3; }
			else if ( tmp == 3 ) { calc_red = tmp_1	; calc_green = tmp_2			   ; calc_blue = COLOR_SPACE_MAX;     }
			else if ( tmp == 4 ) { calc_red = tmp_3	; calc_green = tmp_1			   ; calc_blue = COLOR_SPACE_MAX;     }
			else                 { calc_red = COLOR_SPACE_MAX     ; calc_green = tmp_1 ; calc_blue = tmp_2; }
		}

		red = ((int)brightness * calc_red) / COLOR_SPACE_MAX;
		green = ((int)brightness * calc_green) / COLOR_SPACE_MAX;
		blue = ((int)brightness * calc_blue) / COLOR_SPACE_MAX;

	}
	return 0;
}