#include <avr/io.h>
#include <stdlib.h> // for NULL

#include "lights.h"

static unsigned char led_counters[N_LEDS];
static pattern_t *led_patterns[N_LEDS];

static unsigned char fibonacci[8] = {
	0, 1, 2, 3, 5, 8, 13, 21,
};

static pattern_t boot_pattern[] = {
	{ 1, D_5 },
	{ 0, D_5 },
	{ 1, D_3 },
	{ 0, D_3 },
	{ 1, D_2 },
	{ 0, D_2 },
	{ 1, D_1 },
	{ 0, D_1 },
	{ 1, D_1 },
	{ 0, D_1 },
	{ 1, D_1 },
	{ 0, D_1 },
	{ 1, D_1 },
	{ 0, D_1 },
	{ 1, D_8 },
	{ 0, D_8 },
	PATTERN_END
};

static pattern_t pattern_num[] = {
	{ 0, D_5 },
	{ 1, D_1 }, /* 10 */
	{ 0, D_5 },
	{ 1, D_1 }, /*  9 */
	{ 0, D_5 },
	{ 1, D_1 }, /*  8 */
	{ 0, D_5 },
	{ 1, D_1 }, /*  7 */
	{ 0, D_5 },
	{ 1, D_1 }, /*  6 */
	{ 0, D_5 },
	{ 1, D_1 }, /*  5 */
	{ 0, D_5 },
	{ 1, D_1 }, /*  4 */
	{ 0, D_5 },
	{ 1, D_1 }, /*  3 */
	{ 0, D_5 },
	{ 1, D_1 }, /*  2 */
	{ 0, D_5 },
	{ 1, D_1 }, /*  1 */
	{ 0, D_13 },
	PATTERN_END
};

static pattern_t pattern_invnum[] = {
	{ 1, D_5 },
	{ 0, D_1 }, /* 10 */
	{ 1, D_5 },
	{ 0, D_1 }, /*  9 */
	{ 1, D_5 },
	{ 0, D_1 }, /*  8 */
	{ 1, D_5 },
	{ 0, D_1 }, /*  7 */
	{ 1, D_5 },
	{ 0, D_1 }, /*  6 */
	{ 1, D_5 },
	{ 0, D_1 }, /*  5 */
	{ 1, D_5 },
	{ 0, D_1 }, /*  4 */
	{ 1, D_5 },
	{ 0, D_1 }, /*  3 */
	{ 1, D_5 },
	{ 0, D_1 }, /*  2 */
	{ 1, D_5 },
	{ 0, D_1 }, /*  1 */
	{ 1, D_13 },
	PATTERN_END
};

pattern_t off_pattern[] = {
	{ 0, D_1 },
	PATTERN_END
};

/*
 * This is tricky: we use a single pattern for all three pwmleds,
 * but on some occasions, we want to be able to modify only a single
 * pwmled status without affecting other outputs. For example, during
 * braking, we want to modify only the rear pwmled status. We don't
 * use a separate "braking" pattern for every other pattern used, but instead
 * we change the pwmled0 status regardless of the original value when
 * braking. The rule is the following:
 * - if during braking the pwmled2 (front) is at mode 2, we switch it to
 *   mode 3 (which has the same target current) to avoid flicker.
 * - if pwmled0 (rear) is off, we set it to mode 2
 *   	(if it is with mode 1, we keep it at mode 1)
 * TODO: something similar should be done for the "entering the dark area"
 * 	condition, where we want to switch pwmled2 (front) on, to mode 2.
 */
void pwmleds_update_mode()
{
	unsigned char mode, mode0, mode1, mode2;

	mode = led_patterns[0]->mode;

	mode0 = mode & 3;
	mode1 = (mode >> 2) & 1;
	mode2 = (mode >> 3) & 3;

	if (err_flags.braking && !err_flags.err_battery) {
		mode0 = 2;
		if (mode2 == 2)
			mode2 = 3;
	}

	pwmled_set_mode(0, mode0);
	pwmled_set_mode(1, mode1);
	pwmled_set_mode(2, mode2);
}

void led_set_pattern(unsigned char n, pattern_t *pattern)
{
	if (!pattern)
		pattern = off_pattern;

	led_patterns[n] = pattern;

	led_counters[n] = fibonacci[pattern->duration_fib];

	if (n == 0) {
		pwmleds_update_mode();
	} else if (n < N_LEDS) {
		gpio_set(n - 1, pattern->mode);
	}
}

void init_pattern()
{
	unsigned char i;

	for (i = 0; i < N_LEDS; i++)
		led_set_pattern(i, NULL);

	led_set_pattern(N_ILLUM_LED, boot_pattern);
}

pattern_t *number_pattern(unsigned char num, unsigned char inv)
{
	if (num >= 10)
		num = 10;

	if (inv) {
		return pattern_invnum
			+ sizeof(pattern_invnum)/sizeof(pattern_t)
			- 2 - 2*num;
	} else {
		return pattern_num
			+ sizeof(pattern_num)/sizeof(pattern_t)
			- 2 - 2*num;
	}
}

static pattern_t *pattern_select(unsigned char n)
{
	switch(n) {
	case 0: return pwmled_pattern_select();
	case N_STATUS_LED: return status_led_pattern_select();
	case N_ILLUM_LED:  return illumination_led_pattern_select();
	case N_LASER_LED:  return laser_pattern_select();
	default: return NULL;
	}
}

void pattern_reload()
{
	unsigned char i;

	for (i = 0; i < N_LEDS; i++)
		led_set_pattern(i, pattern_select(i));
}

static void inline pattern_finished(unsigned char n)
{
	unsigned char i;

	led_patterns[n] = NULL;

	if (n == 0) {
		led_set_pattern(0, pattern_select(0));
	} else if (n == N_STATUS_LED) {
		if (!led_patterns[N_ILLUM_LED])
			led_set_pattern(N_ILLUM_LED,
				pattern_select(N_ILLUM_LED));
	} else if (n == N_ILLUM_LED) {
		if (!led_patterns[N_STATUS_LED])
			led_set_pattern(N_STATUS_LED,
				pattern_select(N_STATUS_LED));
	} else {
		led_set_pattern(n, pattern_select(n));
	}
}

void patterns_next_tick()
{
	unsigned char i;

	for (i = 0; i < N_LEDS; i++) {
		if (!led_patterns[i]) {
			pattern_finished(i);
			continue;
		}

		if (--led_counters[i] == 0) {
			pattern_t *p = led_patterns[i];
			p++;
			if (p->duration_fib == 0) { // END
				/* Keep the last state, wait for others */
				pattern_finished(i);
				continue;
			}
			led_set_pattern(i, p);
		}

	}
}