#include <stdlib.h>
#include <avr/power.h>
#include <avr/io.h>
#include <util/delay.h>

void set_frequency(int frequency) {
  int i = F_CPU / (2*8);
  OCR0A = i/frequency;
}

int main(void) {
  // Base clock: 8MHz.
  clock_prescale_set(clock_div_8);

  DDRA |= (1 << DDA4);
  DDRA |= (1 << DDA7);  // OCR1A
  DDRA |= (1 << DDA6);  // OCR0B
  DDRB |= (1 << DDB2);  // OCR0A

  // PORTB |= _BV(DDB2);

  // PORTA |= (1 << DDA7);
  // PORTA |= (1 << DDA6);

  TCCR0A |= (1 << COM0A1) | (1 << COM0B1);  // set non-inverting mode
  // TCCR0A |= (1 << WGM11) | (1 << WGM10);  // set 10bit phase corrected PWM Mode
  TCCR0A |= (1 << WGM10);  // 8 bit PWM
  TCCR0B |= (1 << CS01);  // prescaler

  TCCR1A |= (1 << COM0A1);  // set non-inverting mode
  // TCCR0A |= (1 << WGM11) | (1 << WGM10);  // set 10bit phase corrected PWM Mode
  TCCR1A |= (1 << WGM10);  // 8 bit PWM
  TCCR1B |= (1 << CS01);  // prescaler

  uint32_t tick = 0;
  while (1) {
    tick += 1;
    OCR0A = abs((tick % 511) - 255) * 0.2;  // green
    OCR0B = abs(((tick + 127) % 511) - 255) * 0.2;  // yellow
    OCR1A = abs(((tick + 255) % 511) - 255) * 0.1;  // blue
    _delay_ms(10);

    // set_frequency(tick % 50);
    // _delay_ms(200);
    // PORTA |= _BV(DDA4);
    // _delay_ms(500);
    // PORTA &= ~_BV(DDA4);
    // _delay_ms(500);
  }
  return 0;
}