#include <avr/io.h>

#include "lights.h"

static unsigned char pwm_vals[N_PWMLEDS*N_PWMLED_MODES];
static unsigned char adc_vals[N_PWMLEDS*N_PWMLED_MODES] = {
	/* pwmled0 */
	0x04, 0x14, 0x24, 0x38,
	/* pwmled1 */
	0x04, 0x14, 0x24, 0x38,
	/* pwmled2 */
	0x04, 0x14, 0x24, 0x38,
};

static unsigned char pwmled_state[N_PWMLEDS];
#define ST_DISABLED 0
#define ST_PROBING  1
#define ST_OFF      2
#define ST_ON       3

static unsigned char pwmled_mode[N_PWMLEDS];

static unsigned char pwm_probes[N_PWMLEDS];

static void start_probing(unsigned char n)
{
	pwmled_state[n] = ST_PROBING;
	pwm_set(n, 0);
	pwm_on(n);
	pwm_probes[n] = 0;
}

void pwmled_init()
{
	unsigned char i;

	for (i = 0; i < N_PWMLEDS*N_PWMLED_MODES; i++)
		pwm_vals[i] = 0;

	for (i = 0; i < N_PWMLEDS; i++) {
		start_probing(i);
	}
}

unsigned char pwmled_is_on(unsigned char n)
{
	unsigned char st = pwmled_state[n];
	if (st == ST_PROBING || st == ST_ON)
		return 1;
	else
		return 0;
}

static void inline probing_adc(unsigned char n, uint16_t adcval)
{
	unsigned char need_bigger = 0, i;
	unsigned char *pwm_p = &pwm_vals[n*N_PWMLED_MODES];
	unsigned char *adc_p = &adc_vals[n*N_PWMLED_MODES];
	unsigned char pwm = pwm_probes[n];

#if 0
	log_byte(0xF4);
	log_byte(n);
	log_word(adcval);
#endif

#if 0
	if (pwm == 0 && adcval > 0) { // non-zero voltage with zero PWM?
		pwmled_state[n] = ST_DISABLED;
		log_byte(n);
		log_byte(0xF0);
		log_word(adcval);
		return;
	}
#endif

	for (i = 0; i < N_PWMLED_MODES; i++, pwm_p++, adc_p++) {
		uint16_t adc = *adc_p;
		if (adc >= adcval) {
			*pwm_p = pwm;
			need_bigger = 1;
		}
	}

#if 0
	if ((n == 1 && pwm > 0x35) || adcval != 0) {
		log_byte(n);
		log_byte(0xF3);
		log_byte(pwm);
		log_word(adcval);
	}
#endif

	if (!need_bigger) { // successfully probed
		pwm_off(n);
		// pwm_set(n, 0);
		pwmled_state[n] = ST_OFF;
		log_byte(0xF1);
		log_byte(n);

		return;
	}

	if (pwm >= 0x70) { // over the maximum!
		pwm_off(n);
		pwmled_state[n] = ST_DISABLED;
		log_byte(0xF2);
		log_byte(n);
		// pwm_set(n, 0);
		return;
	}

	// try to increase
	pwm++;
	pwm_probes[n] = pwm;
	pwm_set(n, pwm);
}

// Feedback loop
static void inline on_adc(unsigned char n, uint16_t adcval)
{
#if 0
	uint16_t new_pwm = led_modes[led_mode].pwmval;
	uint16_t old_pwm = new_pwm;
	uint16_t adc_exp = led_modes[led_mode].expected;

	log_word(((adcval & 0xFF) << 8) | old_pwm);

	if (2*adcval > 5*adc_exp) { // >2.5x expected, lower significantly
		new_pwm = 2*old_pwm/3;
	} else if (3*adcval > 4*adc_exp) { // >1.33x expected, lower a bit
		new_pwm = old_pwm - 1;
	} else if (4*adcval < 3*adc_exp) { // 0.75x expected, raise a bit
		new_pwm = old_pwm + 1;
	}

	if (new_pwm > 0x60) { // odpojeno?
		new_pwm = 0x60;
	}
	if (new_pwm < 2) { // zkrat?
		new_pwm = 2;
	}

set_pwm:
	if (new_pwm != old_pwm) {
		led_modes[led_mode].pwmval = new_pwm;
		OCR1D = new_pwm;
	}
	// ADCSRA |= _BV(ADSC);
#endif
}

void pwmled_adc(unsigned char n, uint16_t adcval)
{
	unsigned char i, probing;
	switch (pwmled_state[n]) {
	case ST_PROBING:
		probing_adc(n, adcval);

		probing = 0;
		for (i = 0; i < N_PWMLEDS; i++)
			if (pwmled_state[i] == ST_PROBING)
				probing = 1;

		if (!probing) {
			for (i = 0; i < N_PWMLEDS; i++)
				log_byte(pwmled_state[i]);
				
			for (i = 0; i < N_PWMLEDS*N_PWMLED_MODES; i++)
				log_byte(pwm_vals[i]);
			log_flush();
		}
		
		return;
	case ST_ON:
		on_adc(n, adcval);
		return;
	// WTF am I doing in this function then?
	}
}