#include "timer.h"

void ftoi(float f, int p, long *i, long *d) {
  long prec = 1;
  int x = p;
  while(x>0) {
    prec *= 10;
    x--;
  }
  *d = (long)((f - (long)f) * prec);
  *i = (long)f;
}

void getTime(struct PTimer *time) {
  struct timespec ts;
  clock_gettime(CLOCK_MONOTONIC, &ts);
  time->s = ts.tv_sec;
  time->m = ts.tv_sec*1000;
  time->n = ts.tv_nsec;
}

void doSleep(long seconds, long milliseconds, long nanoseconds) {
  struct timespec ts;
  ts.tv_sec = seconds;
  ts.tv_nsec = nanoseconds + (milliseconds*1000000);
  if (nanosleep(&ts, NULL) < 0)
    printf("ERR\n");
}

int main() {
  printf(" - testing high precision timer - use Ctrl-C to quit\n");
  struct PTimer start_timer;
  getTime(&start_timer);
  struct PTimer last_timer;
  getTime(&last_timer);
  printf("yup\n");
  printf("\tstart PTimer values - s: %d, m: %d, n: %d\n", start_timer.s, start_timer.m, start_timer.n);

  float tickrate = 1000.0f/60.0f; // 60 fps = 16.6666667ms
  printf("\tstart tickrate: %f\n", tickrate);
  struct PTimer sleep_time;
  ftoi(tickrate, 6, &sleep_time.m, &sleep_time.n);
  printf("\tstart tickrate: %ld.%ld\n", sleep_time.m, sleep_time.n);

  sleep(2);

  while(1) {
    struct PTimer current_timer;
    getTime(&current_timer);

    // processing would occur here

    struct PTimer delta_time;
    delta_time.s = current_timer.s - last_timer.s;
    delta_time.m = current_timer.m - last_timer.m;
    delta_time.n = current_timer.n - last_timer.n;

    printf("delta is %ds or %dm, with %dn (%d.%d)\n", delta_time.s, delta_time.m, delta_time.n, delta_time.m, delta_time.n);
    printf("sleeping for %d.%dms\n", sleep_time.m, sleep_time.n);
    
    last_timer = current_timer;
    doSleep(0, sleep_time.m, sleep_time.n);
  }
}