#define _POSIX_C_SOURCE 200112L
#include "../CgeTimer.h"
#include <stdlib.h>
#include <sys/time.h>
#include <time.h>
#include <unistd.h>

enum Type {
    TYPE_UNDEFINED,
    TYPE_OLD_REALTIME,
    TYPE_NEW_REALTIME,
    TYPE_MONOTONIC
};

static int timerType = TYPE_UNDEFINED;

static int checkAvailableTimer(void) {
#if (_POSIX_TIMERS > 0)
    struct timespec ts;
#endif

    if (timerType != TYPE_UNDEFINED)
        return timerType;

#if (_POSIX_TIMERS > 0)
    if (!clock_gettime(CLOCK_MONOTONIC, &ts)) {
        timerType = TYPE_MONOTONIC;
    } else if (!clock_gettime(CLOCK_REALTIME, &ts)) {
        timerType = TYPE_NEW_REALTIME;
    } else
#endif
    timerType = TYPE_OLD_REALTIME;
    return timerType;
}

static void getTimer(uint64_t *sec, uint64_t *nsec) {
#if (_POSIX_TIMERS > 0)
    struct timespec ts;
#endif
    struct timeval tv;

    switch (checkAvailableTimer()) {
#if (_POSIX_TIMERS > 0)
    case TYPE_MONOTONIC:
        clock_gettime(CLOCK_MONOTONIC, &ts);
        *sec = ts.tv_sec;
        *nsec = ts.tv_nsec;
        break;

    case TYPE_NEW_REALTIME:
        clock_gettime(CLOCK_REALTIME, &ts);
        *sec = ts.tv_sec;
        *nsec = ts.tv_nsec;
        break;
#endif

    default:
    case TYPE_OLD_REALTIME:
        gettimeofday(&tv, NULL);
        *sec = tv.tv_sec;
        *nsec = tv.tv_usec * (uint64_t)1000;
        break;
    }
}

int CgeTimerIsMonotonic(void) {
    return checkAvailableTimer() == TYPE_MONOTONIC;
}

uint64_t CgeTimerMilliseconds(void) {
    uint64_t newSec, newNsec;

    getTimer(&newSec, &newNsec);
    return (newSec * 1000u) + (newNsec / 1000000ul);
}

uint64_t CgeTimerNanoseconds(void) {
    uint64_t newSec, newNsec;

    getTimer(&newSec, &newNsec);
    return (newSec * 1000000000ul) + newNsec;
}