#include <stdint.h>
#include <stdbool.h>
#include <msp430.h>

#define interrupt(x) void __attribute__((interrupt (x)))
#define LEDS 6
#define DECAY 14
#define MAX 255

// ",".join([str(int(x**3/256/256)) for x in range(0, 256)])
const uint8_t bright_map[] = {
    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
    0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,3,3,3,3,3,
    4,4,4,4,4,5,5,5,5,5,6,6,6,6,7,7,7,8,8,8,9,9,9,10,10,10,11,11,11,
    12,12,13,13,13,14,14,15,15,16,16,17,17,18,18,19,19,20,20,21,22,
    22,23,23,24,25,25,26,27,27,28,29,29,30,31,32,32,33,34,35,35,36,
    37,38,39,40,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,
    57,59,60,61,62,63,64,66,67,68,69,71,72,73,74,76,77,79,80,81,83,
    84,86,87,88,90,91,93,95,96,98,99,101,103,104,106,108,109,111,
    113,114,116,118,120,122,123,125,127,129,131,133,135,137,139,141,
    143,145,147,149,151,153,155,158,160,162,164,166,169,171,173,176,
    178,180,183,185,188,190,193,195,198,200,203,205,208,210,213,216,
    218,221,224,227,229,232,235,238,241,244,247,250,253
};

void delay_ms(uint16_t ms) {
    while (ms--)
        __delay_cycles(16000);
}

uint16_t debug[8];

int main() {
    // Disable watchdog
    WDTCTL = WDTPW | WDTHOLD;
    
    // 16MHz clock
    BCSCTL1 = CALBC1_16MHZ;
    DCOCTL = CALDCO_16MHZ;

    P2SEL = 0;
    P2SEL2 = 0;
    
    P2DIR = 0x3F;
    
    int16_t cur = 0, dir = 1, i;
    uint16_t val;
    uint8_t pwm = 0, frame = 1;
    uint8_t bright[LEDS];
    uint8_t decay = 0;
    
    for (i = 0; i < LEDS; i++)
        bright[i] = 0;
    
    while (1) {
        val = 0;
        
        for (i = 0; i < LEDS; i++) {
            if (pwm < bright_map[bright[i]])
                val |= 1 << i;
        }
        
        P2OUT = val;
        
        pwm++;
        if (pwm == 0) {
            frame--;
            
            for (i = 0; i < LEDS; i++) {
                if (decay || i != cur) {
                    if (bright[i] <= DECAY)
                        bright[i] = 0;
                    else
                        bright[i] -= DECAY;
                }
            }
            
            if (frame == 0) {
                frame = 5;
                
                cur += dir;
                if (cur == LEDS - 1) {
                    dir = -1;
                    frame = 15;
                    decay = 0;
                } else if (cur == 0) {
                    dir = 1;
                    frame = 15;
                    decay = 0;
                } else {
                    decay = 1;
                }
                
                bright[cur] = MAX;
            }
        }
        
        __delay_cycles(1200);
    }
}