fsfw/timemanager/CCSDSTime.h

#ifndef FSFW_TIMEMANAGER_CCSDSTIME_H_
#define FSFW_TIMEMANAGER_CCSDSTIME_H_

// COULDDO: have calls in Clock.h which return time quality and use timespec accordingly

#include "Clock.h"
#include "clockDefinitions.h"
#include "../returnvalues/HasReturnvaluesIF.h"
#include <cstdint>
#include <cstddef>

bool operator<(const timeval& lhs, const timeval& rhs);
bool operator<=(const timeval& lhs, const timeval& rhs);
bool operator==(const timeval& lhs, const timeval& rhs);
/**
 * static helper class for CCSDS Time Code Formats
 *
 * as described in CCSDS 301.0-B-3
 *
 * Still work in progress
 */
class CCSDSTime: public HasReturnvaluesIF {
public:
    /**
     * The Time code identifications, bits 4-6 in the P-Field
     */
    enum TimeCodeIdentification {
        CCS = 0b101,
        CUC_LEVEL1 = 0b001,
        CUC_LEVEL2 = 0b010,
        CDS = 0b100,
        AGENCY_DEFINED = 0b110
    };
    static const uint8_t P_FIELD_CUC_6B_CCSDS = (CUC_LEVEL1 << 4) + (3 << 2)
			        + 2;
    static const uint8_t P_FIELD_CUC_6B_AGENCY = (CUC_LEVEL2 << 4) + (3 << 2)
			        + 2;
    static const uint8_t P_FIELD_CDS_SHORT = (CDS << 4);
    /**
     * Struct for CDS day-segmented format.
     */
    struct CDS_short {
        uint8_t pField;
        uint8_t dayMSB;
        uint8_t dayLSB;
        uint8_t msDay_hh;
        uint8_t msDay_h;
        uint8_t msDay_l;
        uint8_t msDay_ll;
    };
    /**
     * Struct for the CCS fromat in day of month variation with max resolution
     */
    struct Ccs_seconds {
        uint8_t pField;
        uint8_t yearMSB;
        uint8_t yearLSB;
        uint8_t month;
        uint8_t day;
        uint8_t hour;
        uint8_t minute;
        uint8_t second;
    };

    /**
     * Struct for the CCS fromat in day of month variation with 10E-4 seconds resolution
     */
    struct Ccs_mseconds {
        uint8_t pField;
        uint8_t yearMSB;
        uint8_t yearLSB;
        uint8_t month;
        uint8_t day;
        uint8_t hour;
        uint8_t minute;
        uint8_t second;
        uint8_t secondEminus2;
        uint8_t secondEminus4;
    };

    struct OBT_FLP {
        uint8_t pFiled;
        uint8_t seconds_hh;
        uint8_t seconds_h;
        uint8_t seconds_l;
        uint8_t seconds_ll;
        uint8_t subsecondsMSB;
        uint8_t subsecondsLSB;
    };

    struct TimevalLess {
        bool operator()(const timeval& lhs, const timeval& rhs) const {
            return (lhs < rhs);
        }
    };

    static const uint8_t INTERFACE_ID = CLASS_ID::CCSDS_TIME_HELPER_CLASS;
    static const ReturnValue_t UNSUPPORTED_TIME_FORMAT = MAKE_RETURN_CODE(0);
    static const ReturnValue_t NOT_ENOUGH_INFORMATION_FOR_TARGET_FORMAT =
            MAKE_RETURN_CODE(1);
    static const ReturnValue_t LENGTH_MISMATCH = MAKE_RETURN_CODE(2);
    static const ReturnValue_t INVALID_TIME_FORMAT = MAKE_RETURN_CODE(3);
    static const ReturnValue_t INVALID_DAY_OF_YEAR = MAKE_RETURN_CODE(4);
    static const ReturnValue_t TIME_DOES_NOT_FIT_FORMAT = MAKE_RETURN_CODE(5);

    /**
     * convert a TimeofDay struct to ccs with seconds resolution
     *
     * @param to pointer to a CCS struct
     * @param from pointer to a TimeOfDay Struct
     * @return
     * 		- @c RETURN_OK if OK
     * 		- @c INVALID_TIMECODE if not OK
     */
    static ReturnValue_t convertToCcsds(Ccs_seconds *to,
            Clock::TimeOfDay_t const *from);

    /**
     * Converts to CDS format from timeval.
     * @param to pointer to the CDS struct to generate
     * @param from pointer to a timeval struct which comprises a time of day since UNIX epoch.
     * @return
     * 		- @c RETURN_OK as it assumes a valid timeval.
     */
    static ReturnValue_t convertToCcsds(CDS_short* to, timeval const *from);

    static ReturnValue_t convertToCcsds(OBT_FLP* to, timeval const *from);

    /**
     * convert a TimeofDay struct to ccs with 10E-3 seconds resolution
     *
     * The 10E-4 seconds in the CCS Struct are 0 as the TimeOfDay only has ms resolution
     *
     * @param to pointer to a CCS struct
     * @param from pointer to a TimeOfDay Struct
     * @return
     * 		- @c RETURN_OK if OK
     * 		- @c INVALID_TIMECODE if not OK
     */
    static ReturnValue_t convertToCcsds(Ccs_mseconds *to,
            Clock::TimeOfDay_t const *from);

    /**
     * SHOULDDO: can this be modified to recognize padding?
     * Tries to interpret a Level 1 CCSDS time code
     *
     * It assumes binary formats contain a valid P Field and recognizes the ASCII format
     * by the lack of one.
     *
     * @param to an empty TimeOfDay struct
     * @param from pointer to an CCSDS Time code
     * @param length length of the Time code
     * @return
     * 		- @c RETURN_OK if successful
     * 		- @c UNSUPPORTED_TIME_FORMAT if a (possibly valid) time code is not supported
     * 		- @c LENGTH_MISMATCH if the length does not match the P Field
     * 		- @c INVALID_TIME_FORMAT if the format or a value is invalid
     */
    static ReturnValue_t convertFromCcsds(Clock::TimeOfDay_t *to,
            uint8_t const *from, size_t length);

    /**
     * not implemented yet
     *
     * @param to
     * @param from
     * @return
     */
    static ReturnValue_t convertFromCcsds(timeval *to, uint8_t const *from,
            size_t* foundLength, size_t maxLength);

    static ReturnValue_t convertFromCUC(Clock::TimeOfDay_t *to,
            uint8_t const *from, uint8_t length);

    static ReturnValue_t convertFromCUC(timeval *to, uint8_t const *from,
            size_t* foundLength, size_t maxLength);

    static ReturnValue_t convertFromCUC(timeval *to, uint8_t pField,
            uint8_t const *from, size_t* foundLength, size_t maxLength);

    static ReturnValue_t convertFromCCS(timeval *to, uint8_t const *from,
            size_t* foundLength, size_t maxLength);

    static ReturnValue_t convertFromCCS(timeval *to, uint8_t pField,
            uint8_t const *from, size_t* foundLength, size_t maxLength);

    static ReturnValue_t convertFromCDS(Clock::TimeOfDay_t *to,
            uint8_t const *from, uint8_t length);

    static ReturnValue_t convertFromCDS(timeval *to, uint8_t const *from,
            size_t* foundLength, size_t maxLength);

    static ReturnValue_t convertFromCCS(Clock::TimeOfDay_t *to,
            uint8_t const *from, size_t* foundLength, size_t maxLength);

    static ReturnValue_t convertFromASCII(Clock::TimeOfDay_t *to,
            uint8_t const *from, uint8_t length);

    static uint32_t subsecondsToMicroseconds(uint16_t subseconds);
private:
    CCSDSTime();
    virtual ~CCSDSTime();
    /**
     * checks a ccs time stream for validity
     *
     * Stream may be longer than the actual timecode
     *
     * @param time pointer to an Ccs stream
     * @param length length of stream
     * @return
     */
    static ReturnValue_t checkCcs(const uint8_t* time, uint8_t length);

    static ReturnValue_t checkTimeOfDay(const Clock::TimeOfDay_t *time);

    static const uint32_t SECONDS_PER_DAY = 24 * 60 * 60;
    static const uint32_t SECONDS_PER_NON_LEAP_YEAR = SECONDS_PER_DAY * 365;
    static const uint32_t DAYS_CCSDS_TO_UNIX_EPOCH = 4383; //!< Time difference between CCSDS and POSIX epoch. This is exact, because leap-seconds where not introduced before 1972.
    static const uint32_t SECONDS_CCSDS_TO_UNIX_EPOCH = DAYS_CCSDS_TO_UNIX_EPOCH
            * SECONDS_PER_DAY;
    /**
     * @param dayofYear
     * @param year
     * @param month
     * @param day
     */
    static ReturnValue_t convertDaysOfYear(uint16_t dayofYear, uint16_t year,
            uint8_t *month, uint8_t *day);

    static bool isLeapYear(uint32_t year);
    static ReturnValue_t convertTimevalToTimeOfDay(Clock::TimeOfDay_t* to,
            timeval* from);
};

#endif /* FSFW_TIMEMANAGER_CCSDSTIME_H_ */