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

#include "cmd.h"
#include "serial.h"

#define PWM_MIN   500
#define PWM_MID  1500
#define PWM_MAX  2500

#define PWM_LOCK   PWM_MID
#define PWM_UNLOCK PWM_MAX - 50

#define SERVO_PIN   PB1
#define LOCK_BTN    PD6
#define UNLOCK_BTN  PD7

static inline void servo_init(void)
{
	DDRB |= (1 << SERVO_PIN);

	TCCR1A |= (1 << WGM11) | (1 << COM1A1);
	TCCR1B |= (1 << WGM13) | (1 << CS11);

	ICR1 = 20000;

	DDRD &= ~((1 << LOCK_BTN) | (1 << UNLOCK_BTN));
	PORTD |= (1 << LOCK_BTN) | (1 << UNLOCK_BTN);
}

static inline void lock(void)
{
	OCR1A = PWM_LOCK;
}

static inline void unlock(void)
{
	OCR1A = PWM_UNLOCK;
}

static inline int is_btn_pressed(unsigned char btn)
{
	if (!((PIND >> btn) & 0x01)) {
		_delay_us(2000);
		return !((PIND >> btn) & 0x01);
	}
	
	return 0;
}

static inline void pcint2_init(void)
{
	PCICR |= (1 << PCIE2);
	PCMSK2 |= ((1 << PCINT22) | (1 << PCINT23));
}

int main(void) 
{
	cli();

	servo_init();
	pcint2_init();
	serial_init();

	sei();

	for(;;) {
	}

	return 0;
}

ISR(PCINT2_vect)
{
	if (is_btn_pressed(LOCK_BTN))
		lock();

	if (is_btn_pressed(UNLOCK_BTN))
		unlock();
}