#include "Timekeeper.h"

#include "../../timemanager/Clock.h"
#include "../../globalfunctions/timevalOperations.h"

#include <freertos/FreeRTOS.h>
#include <freertos/task.h>

#include <stdlib.h>
#include <time.h>

//TODO sanitize input?
//TODO much of this code can be reused for tick-only systems

uint16_t Clock::leapSeconds = 0;
MutexIF* Clock::timeMutex = nullptr;

uint32_t Clock::getTicksPerSecond(void) {
    return 1000;
}

ReturnValue_t Clock::setClock(const TimeOfDay_t* time) {

    timeval time_timeval;

    ReturnValue_t result = convertTimeOfDayToTimeval(time, &time_timeval);
    if (result != HasReturnvaluesIF::RETURN_OK){
        return result;
    }

    return setClock(&time_timeval);
}

ReturnValue_t Clock::setClock(const timeval* time) {
    timeval uptime = getUptime();

    timeval offset = *time - uptime;

    Timekeeper::instance()->setOffset(offset);

    return HasReturnvaluesIF::RETURN_OK;
}

ReturnValue_t Clock::getClock_timeval(timeval* time) {
    timeval uptime = getUptime();

    timeval offset = Timekeeper::instance()->getOffset();

    *time = offset + uptime;

    return HasReturnvaluesIF::RETURN_OK;
}

ReturnValue_t Clock::getUptime(timeval* uptime) {
    *uptime = getUptime();

    return HasReturnvaluesIF::RETURN_OK;
}

timeval Clock::getUptime() {
    TickType_t ticksSinceStart = xTaskGetTickCount();
    return Timekeeper::ticksToTimeval(ticksSinceStart);
}

ReturnValue_t Clock::getUptime(uint32_t* uptimeMs) {
    timeval uptime = getUptime();
    *uptimeMs = uptime.tv_sec * 1000 + uptime.tv_usec / 1000;
    return HasReturnvaluesIF::RETURN_OK;
}


//uint32_t Clock::getUptimeSeconds() {
//	timeval uptime = getUptime();
//	return uptime.tv_sec;
//}


ReturnValue_t Clock::getClock_usecs(uint64_t* time) {
    timeval time_timeval;
    ReturnValue_t result = getClock_timeval(&time_timeval);
    if (result != HasReturnvaluesIF::RETURN_OK) {
        return result;
    }
    *time = time_timeval.tv_sec * 1000000 + time_timeval.tv_usec;
    return HasReturnvaluesIF::RETURN_OK;
}

ReturnValue_t Clock::getDateAndTime(TimeOfDay_t* time) {
    timeval time_timeval;
    ReturnValue_t result = getClock_timeval(&time_timeval);
    if (result != HasReturnvaluesIF::RETURN_OK) {
        return result;
    }
    struct tm time_tm;

    gmtime_r(&time_timeval.tv_sec,&time_tm);

    time->year = time_tm.tm_year + 1900;
    time->month = time_tm.tm_mon + 1;
    time->day = time_tm.tm_mday;

    time->hour = time_tm.tm_hour;
    time->minute = time_tm.tm_min;
    time->second = time_tm.tm_sec;

    time->usecond = time_timeval.tv_usec;


    return HasReturnvaluesIF::RETURN_OK;
}

ReturnValue_t Clock::convertTimeOfDayToTimeval(const TimeOfDay_t* from,
        timeval* to) {
    struct tm time_tm = {};

    time_tm.tm_year = from->year - 1900;
    time_tm.tm_mon = from->month - 1;
    time_tm.tm_mday = from->day;

    time_tm.tm_hour = from->hour;
    time_tm.tm_min = from->minute;
    time_tm.tm_sec = from->second;

    time_t seconds = mktime(&time_tm);

    to->tv_sec = seconds;
    to->tv_usec = from->usecond;
    //Fails in 2038..
    return HasReturnvaluesIF::RETURN_OK;
}

ReturnValue_t Clock::convertTimevalToJD2000(timeval time, double* JD2000) {
    *JD2000 = (time.tv_sec - 946728000. + time.tv_usec / 1000000.) / 24.
            / 3600.;
    return HasReturnvaluesIF::RETURN_OK;
}

ReturnValue_t Clock::convertUTCToTT(timeval utc, timeval* tt) {
    //SHOULDDO: works not for dates in the past (might have less leap seconds)
    if (timeMutex == nullptr) {
        return HasReturnvaluesIF::RETURN_FAILED;
    }

    uint16_t leapSeconds;
    ReturnValue_t result = getLeapSeconds(&leapSeconds);
    if (result != HasReturnvaluesIF::RETURN_OK) {
        return result;
    }
    timeval leapSeconds_timeval = { 0, 0 };
    leapSeconds_timeval.tv_sec = leapSeconds;

    //initial offset between UTC and TAI
    timeval UTCtoTAI1972 = { 10, 0 };

    timeval TAItoTT = { 32, 184000 };

    *tt = utc + leapSeconds_timeval + UTCtoTAI1972 + TAItoTT;

    return HasReturnvaluesIF::RETURN_OK;
}

ReturnValue_t Clock::setLeapSeconds(const uint16_t leapSeconds_) {
    if (checkOrCreateClockMutex() != HasReturnvaluesIF::RETURN_OK) {
        return HasReturnvaluesIF::RETURN_FAILED;
    }
    ReturnValue_t result = timeMutex->lockMutex(MutexIF::TimeoutType::BLOCKING);
    if (result != HasReturnvaluesIF::RETURN_OK) {
        return result;
    }

    leapSeconds = leapSeconds_;

    result = timeMutex->unlockMutex();
    return result;
}

ReturnValue_t Clock::getLeapSeconds(uint16_t* leapSeconds_) {
    if (timeMutex == NULL) {
        return HasReturnvaluesIF::RETURN_FAILED;
    }
    ReturnValue_t result = timeMutex->lockMutex(MutexIF::TimeoutType::BLOCKING);
    if (result != HasReturnvaluesIF::RETURN_OK) {
        return result;
    }

    *leapSeconds_ = leapSeconds;

    result = timeMutex->unlockMutex();
    return result;
}

ReturnValue_t Clock::checkOrCreateClockMutex() {
    if (timeMutex == NULL) {
        MutexFactory* mutexFactory = MutexFactory::instance();
        if (mutexFactory == NULL) {
            return HasReturnvaluesIF::RETURN_FAILED;
        }
        timeMutex = mutexFactory->createMutex();
        if (timeMutex == NULL) {
            return HasReturnvaluesIF::RETURN_FAILED;
        }
    }
    return HasReturnvaluesIF::RETURN_OK;
}