// License MIT
// Compatibility layer done by Kamil Trzcinski <ayufan@ayufan.eu>

#include "wiringPi.h"

static uint64_t epochMilli, epochMicro;

int wiringPiSetup()
{
  initialiseEpoch();
  return setup();
}

int digitalRead(int gpio)
{
  return input_gpio(gpio);
}

void digitalWrite(int gpio, int value)
{
  output_gpio(gpio, value);
}

void pinMode(int gpio, int direction)
{
  setup_gpio(gpio, direction, PUD_UP);
}

//
// The functions belowe are copied from wiringPi
//

void initialiseEpoch (void)
{
  struct timeval tv ;

  gettimeofday (&tv, NULL) ;
  epochMilli = (uint64_t)tv.tv_sec * (uint64_t)1000    + (uint64_t)(tv.tv_usec / 1000) ;
  epochMicro = (uint64_t)tv.tv_sec * (uint64_t)1000000 + (uint64_t)(tv.tv_usec) ;
}

void delayMicrosecondsHard (unsigned int howLong)
{
  struct timeval tNow, tLong, tEnd ;

  gettimeofday (&tNow, NULL) ;
  tLong.tv_sec  = howLong / 1000000 ;
  tLong.tv_usec = howLong % 1000000 ;
  timeradd (&tNow, &tLong, &tEnd) ;

  while (timercmp (&tNow, &tEnd, <))
    gettimeofday (&tNow, NULL) ;
}

void delayMicroseconds (unsigned int howLong)
{
  struct timespec sleeper ;
  unsigned int uSecs = howLong % 1000000 ;
  unsigned int wSecs = howLong / 1000000 ;

  /**/ if (howLong ==   0)
    return ;
  else if (howLong  < 100)
    delayMicrosecondsHard (howLong) ;
  else
  {
    sleeper.tv_sec  = wSecs ;
    sleeper.tv_nsec = (long)(uSecs * 1000L) ;
    nanosleep (&sleeper, NULL) ;
  }
}

void delay (unsigned int howLong)
{
  struct timespec sleeper, dummy ;

  sleeper.tv_sec  = (time_t)(howLong / 1000) ;
  sleeper.tv_nsec = (long)(howLong % 1000) * 1000000 ;

  nanosleep (&sleeper, &dummy) ;
}

unsigned int millis (void)
{
  struct timeval tv ;
  uint64_t now ;

  gettimeofday (&tv, NULL) ;
  now  = (uint64_t)tv.tv_sec * (uint64_t)1000 + (uint64_t)(tv.tv_usec / 1000) ;

  return (uint32_t)(now - epochMilli) ;
}

unsigned int micros (void)
{
  struct timeval tv ;
  uint64_t now ;

  gettimeofday (&tv, NULL) ;
  now  = (uint64_t)tv.tv_sec * (uint64_t)1000000 + (uint64_t)tv.tv_usec ;

  return (uint32_t)(now - epochMicro) ;
}