#define CHRONO_UTILITIES_TIMESPAN_INTEGER_SCALE_OVERLOADS

#include "../chrono/datetime.h"
#include "../chrono/format.h"
#include "../chrono/period.h"
#include "../chrono/timespan.h"
#include "../conversion/conversionexception.h"
#include "../tests/testutils.h"

#include <cppunit/TestFixture.h>
#include <cppunit/extensions/HelperMacros.h>

#include <chrono>
#include <cmath>
#include <iostream>

using namespace std;
using namespace CppUtilities;
using namespace CppUtilities::Literals;

using namespace CPPUNIT_NS;

// compile-time checks for DateTime class
static_assert(DateTime().isNull(), "isNull()");
static_assert(DateTime(1).totalTicks() == 1, "construction with ticks");
static_assert(DateTime(2) == DateTime(2), "operator ==");
static_assert(DateTime(2) != DateTime(3), "operator !=");
static_assert(DateTime(2) < DateTime(3), "operator <");
static_assert(DateTime(3) > DateTime(2), "operator >");
static_assert(DateTime::eternity().isEternity() && !DateTime().isEternity(), "isEternity()");
static constexpr auto dateFromUnixEpoch(
    DateTime::unixEpochStart() + TimeSpan::fromHours(1.0) + TimeSpan::fromMinutes(2.0) + TimeSpan::fromSeconds(3.1256789));
static_assert(dateFromUnixEpoch.dayOfWeek() == DayOfWeek::Thursday, "dayOfWeek()");
static_assert(dateFromUnixEpoch.hour() == 1, "hour()");
static_assert(dateFromUnixEpoch.minute() == 2, "minute()");
static_assert(dateFromUnixEpoch.second() == 3, "second()");
static_assert(dateFromUnixEpoch.millisecond() == 125, "millisecond()");
static_assert(dateFromUnixEpoch.microsecond() == 678, "microsecond()");
static_assert(dateFromUnixEpoch.nanosecond() == 900, "nanosecond()");
static_assert(dateFromUnixEpoch.isSameDay(DateTime::unixEpochStart()), "isSameDay()");
static_assert(!dateFromUnixEpoch.isSameDay(DateTime::unixEpochStart() + TimeSpan::fromHours(24.0)), "!isSameDay()");

// compile-time checks for TimeSpan class
static_assert(TimeSpan().isNull(), "isNull()");
static_assert(TimeSpan(1).totalTicks() == 1, "construction with ticks");
static_assert(TimeSpan(-1).isNegative() && !TimeSpan(1).isNegative(), "isNegative()");
static_assert(TimeSpan::infinity().isInfinity() && !TimeSpan().isInfinity(), "isInfinity()");
static_assert(TimeSpan::negativeInfinity().isNegativeInfinity() && !TimeSpan().isNegativeInfinity(), "isNegativeInfinity()");
static_assert(TimeSpan::fromMilliseconds(1.0125).nanoseconds() == 500, "fromMilliseconds()/nanoseconds()");
static_assert(TimeSpan::fromMilliseconds(1.0125).microseconds() == 12, "fromMilliseconds()/microseconds()");
static_assert(TimeSpan::fromMilliseconds(1.0125).milliseconds() == 1, "fromMilliseconds()/milliseconds()");
static_assert(TimeSpan::fromSeconds(TimeSpan::TickType(61)).seconds() == 1, "fromSeconds()/seconds()");
static_assert(TimeSpan::fromSeconds(TimeSpan::TickType(61)).minutes() == 1, "fromSeconds()/minutes()");
static_assert(TimeSpan::fromMinutes(TimeSpan::TickType(61)).minutes() == 1, "fromMinutes()/minutes()");
static_assert(TimeSpan::fromHours(TimeSpan::TickType(25)).hours() == 1, "fromMinutes()/hours()");
static_assert(TimeSpan::fromDays(20.5).days() == 20, "fromDays()/days()");
static_assert(TimeSpan::fromMinutes(1.5).totalMicroseconds() == 90e6, "totalMicroseconds()");
static_assert(TimeSpan::fromMinutes(1.5).totalMilliseconds() == 90e3, "totalMilliseconds()");
static_assert(TimeSpan::fromMinutes(1.5).totalSeconds() == 90.0, "totalSeconds()");
static_assert(TimeSpan::fromHours(1.5).totalMinutes() == 90.0, "totalMinutes()");
static_assert(TimeSpan::fromDays(1.5).totalHours() == 36.0, "totalHours()");
static_assert(TimeSpan::fromDays(20.5).totalDays() == 20.5, "totalDays()");

/*!
 * \brief The ChronoTests class tests classes and functions provided by the files inside the chrono directory.
 * \remarks Before committing any changes to this test, run with different timezones to prevent
 *          mistakes like timezone-dependent checks. (Eg. set environment variable TZ to different
 *          values like 'UTC' or 'America/Los_Angeles'.)
 */
class ChronoTests : public TestFixture {
    CPPUNIT_TEST_SUITE(ChronoTests);
    CPPUNIT_TEST(testDateTime);
    CPPUNIT_TEST(testDateTimeExpression);
    CPPUNIT_TEST(testTimeSpan);
    CPPUNIT_TEST(testOperators);
    CPPUNIT_TEST(testPeriod);
    CPPUNIT_TEST(testHashing);
    CPPUNIT_TEST_SUITE_END();

public:
    void setUp()
    {
    }
    void tearDown()
    {
    }

    void testDateTime();
    void testDateTimeExpression();
    void testTimeSpan();
    void testOperators();
    void testPeriod();
    void testHashing();
};

CPPUNIT_TEST_SUITE_REGISTRATION(ChronoTests);

/*!
 * \brief Tests most important DateTime features.
 */
void ChronoTests::testDateTime()
{
    // test year(), month(), ...
    CPPUNIT_ASSERT_EQUAL(DateTime::daysInMonth(2000, 2), 29);
    CPPUNIT_ASSERT_EQUAL(DateTime::daysInMonth(2001, 2), 28);
    CPPUNIT_ASSERT_EQUAL(DateTime::daysInMonth(2100, 2), 28);
    const auto test1 = DateTime::fromDateAndTime(2012, 2, 29, 15, 34, 20, 33.0);
    CPPUNIT_ASSERT_EQUAL(2012, test1.year());
    CPPUNIT_ASSERT_EQUAL(2, test1.month());
    CPPUNIT_ASSERT_EQUAL(29, test1.day());
    CPPUNIT_ASSERT_EQUAL(15, test1.hour());
    CPPUNIT_ASSERT_EQUAL(34, test1.minute());
    CPPUNIT_ASSERT_EQUAL(20, test1.second());
    CPPUNIT_ASSERT_EQUAL(33, test1.millisecond());
    CPPUNIT_ASSERT_EQUAL(DayOfWeek::Wednesday, test1.dayOfWeek());
    CPPUNIT_ASSERT_EQUAL((31 + 29), test1.dayOfYear());
    CPPUNIT_ASSERT(test1.isLeapYear());
    CPPUNIT_ASSERT(test1.isSameDay(test1 + TimeSpan::fromHours(8.0)));
    CPPUNIT_ASSERT(!test1.isSameDay(test1 + TimeSpan::fromHours(9.0)));
    CPPUNIT_ASSERT_EQUAL("Wed 2012-02-29 15:34:20.033"s, test1.toString(DateTimeOutputFormat::DateTimeAndShortWeekday));
    const auto test2 = DateTime::fromDateAndTime(1, 1, 1, 15, 34, 20, 33.0);
    CPPUNIT_ASSERT_EQUAL(1, test2.year());
    CPPUNIT_ASSERT_EQUAL(1, test2.month());
    CPPUNIT_ASSERT_EQUAL(1, test2.day());
    CPPUNIT_ASSERT_EQUAL(15, test2.hour());
    CPPUNIT_ASSERT_EQUAL(34, test2.minute());
    CPPUNIT_ASSERT_EQUAL(20, test2.second());
    CPPUNIT_ASSERT_EQUAL(33, test2.millisecond());

    // test fromTimeStamp()/toTimeStamp()
    const auto timeStamp = static_cast<time_t>(1453840331);
    const auto fromTimeStampGmt = DateTime::fromTimeStampGmt(timeStamp), fromTimeStamp = DateTime::fromTimeStamp(timeStamp);
    CPPUNIT_ASSERT_EQUAL("Tue 2016-01-26 20:32:11"s, fromTimeStampGmt.toString(DateTimeOutputFormat::DateTimeAndShortWeekday));
    CPPUNIT_ASSERT(fabs((fromTimeStamp - fromTimeStampGmt).totalDays()) <= 1.0);
    CPPUNIT_ASSERT_EQUAL(DateTime(), DateTime::fromTimeStamp(0));
    CPPUNIT_ASSERT_EQUAL(timeStamp, fromTimeStampGmt.toTimeStamp());

    // test fromChronoTimePointGmt()
    const auto fromChronoTimePointGmt = DateTime::fromChronoTimePointGmt(chrono::system_clock::from_time_t(timeStamp));
    CPPUNIT_ASSERT_EQUAL("Tue 2016-01-26 20:32:11"s, fromChronoTimePointGmt.toString(DateTimeOutputFormat::DateTimeAndShortWeekday));

    // test whether ConversionException() is thrown when invalid values are specified
    CPPUNIT_ASSERT_THROW(DateTime::fromDate(0, 1, 1), ConversionException);
    CPPUNIT_ASSERT_THROW(DateTime::fromDate(2012, 15, 1), ConversionException);
    CPPUNIT_ASSERT_THROW(DateTime::fromDateAndTime(0, 2, 29, 15, 34, 20, 33), ConversionException);
    CPPUNIT_ASSERT_THROW(DateTime::fromDateAndTime(2013, 2, 29, 15, 34, 20, 33), ConversionException);
    CPPUNIT_ASSERT_THROW(DateTime::fromDateAndTime(2012, 2, 29, 15, 61, 20, 33), ConversionException);
    CPPUNIT_ASSERT_THROW(DateTime::fromDateAndTime(2012, 4, 31, 15, 0, 20, 33), ConversionException);
    CPPUNIT_ASSERT_THROW(DateTime::fromDateAndTime(2012, 3, 31, 15, 0, 61, 33), ConversionException);
    CPPUNIT_ASSERT_THROW(DateTime::fromDateAndTime(2012, 1, 1, 61, 2, 1), ConversionException);
    CPPUNIT_ASSERT_THROW(DateTime::fromDateAndTime(2012, 1, 1, 15, 2, 1, 2000.0), ConversionException);

    // test fromString()/toString()
    CPPUNIT_ASSERT_EQUAL(test1, DateTime::fromString("2012-02-29 15:34:20.033"));
    CPPUNIT_ASSERT_EQUAL_MESSAGE("surplus parts ignored", test1, DateTime::fromString("2012-02-29 15:34:20.033:12"));
    CPPUNIT_ASSERT_EQUAL("2012-02-29 15:34:20.033"s, test1.toString(DateTimeOutputFormat::DateAndTime, false));
    CPPUNIT_ASSERT_THROW(TimeSpan::fromString("2012-02-29 15:34:34:20.033"), ConversionException);
    const auto test3 = DateTime::fromIsoString("2016-08-29T21:32:31.125+02:00");
    CPPUNIT_ASSERT_EQUAL("2016-08-29T21:32:31.125+02:00"s, test3.first.toIsoString(test3.second));
    CPPUNIT_ASSERT_THROW(DateTime::fromString("#"), ConversionException);
    // test accuracy (of 100 nanoseconds)
    const auto test4 = DateTime::fromIsoString("2017-08-23T19:40:15.985077682+02:30");
    CPPUNIT_ASSERT_EQUAL(2.5, test4.second.totalHours());
    CPPUNIT_ASSERT_EQUAL(15, test4.first.second());
    CPPUNIT_ASSERT_EQUAL(985, test4.first.millisecond());
    CPPUNIT_ASSERT_EQUAL(77, test4.first.microsecond());
    CPPUNIT_ASSERT_EQUAL(600, test4.first.nanosecond());
    CPPUNIT_ASSERT_EQUAL("2017-08-23T19:40:15.9850776+02:30"s, test4.first.toIsoString(test4.second));
    // test negative delta
    const auto test5 = DateTime::fromIsoString("2017-08-23T19:40:15.985077682-02:30");
    CPPUNIT_ASSERT_EQUAL(-2.5, test5.second.totalHours());
    CPPUNIT_ASSERT_EQUAL(15, test5.first.second());
    CPPUNIT_ASSERT_EQUAL(985, test5.first.millisecond());
    CPPUNIT_ASSERT_EQUAL(77, test5.first.microsecond());
    CPPUNIT_ASSERT_EQUAL(600, test5.first.nanosecond());
    CPPUNIT_ASSERT_EQUAL("2017-08-23T19:40:15.9850776-02:30"s, test5.first.toIsoString(test5.second));
    // test further variants
    CPPUNIT_ASSERT_EQUAL_MESSAGE("only year", DateTime::fromDate(2008), DateTime::fromIsoStringGmt("2008"));
    CPPUNIT_ASSERT_EQUAL_MESSAGE("only year and month", DateTime::fromDate(2008, 12), DateTime::fromIsoStringGmt("2008-12"));
    CPPUNIT_ASSERT_EQUAL_MESSAGE("only date", DateTime::fromDate(2008, 12, 5), DateTime::fromIsoStringGmt("2008-12-05"));
    CPPUNIT_ASSERT_EQUAL_MESSAGE("Zulu time", TimeSpan(), DateTime::fromIsoString("2017-08-23T19:40:15.985077682Z").second);
    CPPUNIT_ASSERT_EQUAL_MESSAGE("no minutes", TimeSpan::fromHours(3.0), DateTime::fromIsoString("2017-08-23T19:40:15.985077682+03").second);
    const auto test6 = DateTime::fromIsoString("1970-01-01T01:02:03+01:00");
    CPPUNIT_ASSERT_EQUAL_MESSAGE("no seconds fraction (positive timezone offset, 1)", DateTime::fromDateAndTime(1970, 1, 1, 1, 2, 3), test6.first);
    CPPUNIT_ASSERT_EQUAL_MESSAGE("no seconds fraction (positive timezone offset, 2)", TimeSpan::fromHours(1.0), test6.second);
    const auto test7 = DateTime::fromIsoString("2021-05-20T23:02:45-04:00");
    CPPUNIT_ASSERT_EQUAL_MESSAGE("no seconds fraction (negative timezone offset, 1)", DateTime::fromDateAndTime(2021, 5, 20, 23, 2, 45), test7.first);
    CPPUNIT_ASSERT_EQUAL_MESSAGE("no seconds fraction (negative timezone offset, 2)", TimeSpan::fromHours(-4.0), test7.second);
    // implied separators / too many digits
    CPPUNIT_ASSERT_EQUAL_MESSAGE("no separators", test5.first - test5.second, DateTime::fromIsoStringGmt("20170823T194015.985077682-0230"));
    CPPUNIT_ASSERT_EQUAL_MESSAGE(
        "not even T separator", DateTime::fromDateAndTime(2017, 8, 23, 19, 40, 15), DateTime::fromIsoStringGmt("20170823194015"));
    CPPUNIT_ASSERT_THROW_MESSAGE("too many digits after seconds", DateTime::fromIsoString("2017082319401516"), ConversionException);
    CPPUNIT_ASSERT_THROW_MESSAGE("too many digits after timezone offset", DateTime::fromIsoString("20170823194015.16+02300"), ConversionException);
    // test invalid characters
    CPPUNIT_ASSERT_THROW_MESSAGE("digits after Z", DateTime::fromIsoString("2017-O8-23T19:40:15.985077682Z02:00"), ConversionException);
    CPPUNIT_ASSERT_THROW_MESSAGE("invalid letter", DateTime::fromIsoString("2017-O8-23T19:40:15.985077682:+02:00"), ConversionException);
    CPPUNIT_ASSERT_THROW_MESSAGE("invalid T", DateTime::fromIsoString("2017-08-23T19:T40:15.985077682+02:00"), ConversionException);
    CPPUNIT_ASSERT_THROW_MESSAGE("invalid -", DateTime::fromIsoString("2017-08-23T19:40-15.985077682+02:00"), ConversionException);
    CPPUNIT_ASSERT_THROW_MESSAGE("invalid .", DateTime::fromIsoString("2017-08.5-23T19:40:15.985077682+02:00"), ConversionException);
    CPPUNIT_ASSERT_THROW_MESSAGE("invalid :", DateTime::fromIsoString("2017:08-23T19:40:15.985077682+02:00"), ConversionException);
    CPPUNIT_ASSERT_THROW_MESSAGE("invalid :", DateTime::fromIsoString("2017-08-23T19:40:15:985077682+02:00"), ConversionException);
    // ISO string via toString() format option
    CPPUNIT_ASSERT_EQUAL("1234-05-06T07:08:09.0105005"s, DateTime::fromDateAndTime(1234, 5, 6, 7, 8, 9, 10.5005).toString(DateTimeOutputFormat::Iso));
    CPPUNIT_ASSERT_EQUAL("1234-05-06T07:08:09.0105005"s,
        DateTime::fromDateAndTime(1234, 5, 6, 7, 8, 9, 10.5005).toString(DateTimeOutputFormat::IsoOmittingDefaultComponents));
    CPPUNIT_ASSERT_EQUAL("1234-05-06T07:08:09.010500"s,
        DateTime::fromDateAndTime(1234, 5, 6, 7, 8, 9, 10.500).toString(DateTimeOutputFormat::IsoOmittingDefaultComponents));
    CPPUNIT_ASSERT_EQUAL(
        "1234-05-06T07:08:09.010"s, DateTime::fromDateAndTime(1234, 5, 6, 7, 8, 9, 10).toString(DateTimeOutputFormat::IsoOmittingDefaultComponents));
    CPPUNIT_ASSERT_EQUAL(
        "1234-05-06T07:08:09"s, DateTime::fromDateAndTime(1234, 5, 6, 7, 8, 9).toString(DateTimeOutputFormat::IsoOmittingDefaultComponents));
    CPPUNIT_ASSERT_EQUAL(
        "1234-05-06T07:08"s, DateTime::fromDateAndTime(1234, 5, 6, 7, 8).toString(DateTimeOutputFormat::IsoOmittingDefaultComponents));
    CPPUNIT_ASSERT_EQUAL("1234-05-06T07"s, DateTime::fromDateAndTime(1234, 5, 6, 7).toString(DateTimeOutputFormat::IsoOmittingDefaultComponents));
    CPPUNIT_ASSERT_EQUAL("1234-05-06"s, DateTime::fromDateAndTime(1234, 5, 6).toString(DateTimeOutputFormat::IsoOmittingDefaultComponents));
    CPPUNIT_ASSERT_EQUAL("1234-05"s, DateTime::fromDateAndTime(1234, 5).toString(DateTimeOutputFormat::IsoOmittingDefaultComponents));
    CPPUNIT_ASSERT_EQUAL("1234"s, DateTime::fromDateAndTime(1234).toString(DateTimeOutputFormat::IsoOmittingDefaultComponents));
    CPPUNIT_ASSERT_EQUAL("0001"s, DateTime().toString(DateTimeOutputFormat::IsoOmittingDefaultComponents));

// test now() and exactNow() (or at least whether both behave the same)
#if defined(PLATFORM_UNIX)
    const auto delta = DateTime::gmtNow() - DateTime::exactGmtNow();
    CPPUNIT_ASSERT(delta < TimeSpan::fromSeconds(2.0) && delta > TimeSpan::fromSeconds(-2.0));
#endif
}

/*!
 * \brief Tests parsing a DateTimeExpression. Checks for the parts in particular.
 */
void ChronoTests::testDateTimeExpression()
{
    // check adding ISO timestamp parts one-by-one and serialization back to string
    auto expr = DateTimeExpression::fromIsoString("1");
    auto parts = DateTimeParts::Year;
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts, expr.parts);
    CPPUNIT_ASSERT_EQUAL("0001"s, expr.toIsoString());
    expr = DateTimeExpression::fromIsoString("1-1");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::Month, expr.parts);
    CPPUNIT_ASSERT_EQUAL("0001-01"s, expr.toIsoString());
    expr = DateTimeExpression::fromIsoString("1-1-1");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::Day, expr.parts);
    CPPUNIT_ASSERT_EQUAL("0001-01-01"s, expr.toIsoString());
    expr = DateTimeExpression::fromIsoString("1-1-1T0");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::Hour, expr.parts);
    CPPUNIT_ASSERT_EQUAL("0001-01-01T00"s, expr.toIsoString());
    expr = DateTimeExpression::fromIsoString("1-1-1T0:0");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::Minute, expr.parts);
    CPPUNIT_ASSERT_EQUAL("0001-01-01T00:00"s, expr.toIsoString());
    expr = DateTimeExpression::fromIsoString("1-1-1T0:0:0");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::Second, expr.parts);
    CPPUNIT_ASSERT_EQUAL("0001-01-01T00:00:00"s, expr.toIsoString());
    expr = DateTimeExpression::fromIsoString("1-1-1T0:0:0.0");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::SubSecond, expr.parts);
    CPPUNIT_ASSERT_EQUAL("0001-01-01T00:00:00.000"s, expr.toIsoString());
    expr = DateTimeExpression::fromIsoString("1-1-1T0:0:0.0+0");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::DeltaHour, expr.parts);
    CPPUNIT_ASSERT_EQUAL("0001-01-01T00:00:00.000+00"s, expr.toIsoString());
    expr = DateTimeExpression::fromIsoString("1-1-1T0:0:0.0-0:0");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::DeltaMinute, expr.parts);
    CPPUNIT_ASSERT_EQUAL("0001-01-01T00:00:00.000+00:00"s, expr.toIsoString());

    // check that omitting parts in the middle is not possible anyways
    CPPUNIT_ASSERT_THROW(DateTimeExpression::fromIsoString("1-1T0"), ConversionException);

    // check ::fromString()
    expr = DateTimeExpression::fromString("1");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts = DateTimeParts::Year, expr.parts);
    expr = DateTimeExpression::fromString("1/1");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::Month, expr.parts);
    expr = DateTimeExpression::fromString("1/1/1");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::Day, expr.parts);
    expr = DateTimeExpression::fromString("1/1/1 0");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::Hour, expr.parts);
    expr = DateTimeExpression::fromString("1/1/1 0:0");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::Minute, expr.parts);
    expr = DateTimeExpression::fromString("1/1/1 0:0:0");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::Second, expr.parts);
    expr = DateTimeExpression::fromString("1/1/1 0:0:0.0");
    CPPUNIT_ASSERT_EQUAL(DateTime(), expr.value);
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), expr.delta);
    CPPUNIT_ASSERT_EQUAL(parts |= DateTimeParts::SubSecond, expr.parts);
}

/*!
 * \brief Tests most important TimeSpan features.
 */
void ChronoTests::testTimeSpan()
{
    // test various usages of fromString(...), all other from...() functions and the plus operator
    CPPUNIT_ASSERT_EQUAL(TimeSpan(), TimeSpan::fromString(string()));
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromSeconds(5.0), TimeSpan::fromString("5.0"));
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromMinutes(5.5), TimeSpan::fromString("5:30"));
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromHours(7.0) + TimeSpan::fromMinutes(5.5), TimeSpan::fromString("7:5:30"));
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromDays(14.0), TimeSpan::fromString("14:::"));
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromDays(14.0), TimeSpan::fromString("14d"));
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromDays(14.0) + TimeSpan::fromHours(5.0), TimeSpan::fromString("14d 5h"));
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromDays(14.0) + TimeSpan::fromMinutes(5.0), TimeSpan::fromString(" 14d   5m"));
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromDays(14.0) + TimeSpan::fromMinutes(5.0) + TimeSpan::fromSeconds(24.5), TimeSpan::fromString("2 w 24.5s 5m "));
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromDays(14.0) + TimeSpan::fromSeconds(24.5), TimeSpan::fromString("2 w 24.5"));
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromDays(14.0) + TimeSpan::fromString("1:2:3:4"), TimeSpan::fromString("2 w 1:2:3:4"));
    CPPUNIT_ASSERT_THROW(TimeSpan::fromString("2:34a:53:32.5"), ConversionException);
    CPPUNIT_ASSERT_THROW(TimeSpan::fromString("1:2:3:4:5"), ConversionException);

    // test fromString(...) again and days(), hours(), ...
    const auto test1 = TimeSpan::fromString("2:34:53:2.5");
    CPPUNIT_ASSERT_EQUAL(3, test1.days());
    CPPUNIT_ASSERT_EQUAL(10, test1.hours());
    CPPUNIT_ASSERT_EQUAL(53, test1.minutes());
    CPPUNIT_ASSERT_EQUAL(2, test1.seconds());
    CPPUNIT_ASSERT_EQUAL(500, test1.milliseconds());
    CPPUNIT_ASSERT(test1.totalDays() > 3.0 && test1.totalDays() < 4.0);
    CPPUNIT_ASSERT(test1.totalHours() > (2 * 24 + 34) && test1.totalHours() < (2 * 24 + 35));
    CPPUNIT_ASSERT(test1.totalMinutes() > (2 * 24 * 60 + 34 * 60 + 53) && test1.totalHours() < (2 * 24 * 60 + 34 * 60 + 54));

    // test toString(...)
    CPPUNIT_ASSERT_EQUAL("3 d 10 h 53 min 2 s 500 ms"s, test1.toString(TimeSpanOutputFormat::WithMeasures, false));
    CPPUNIT_ASSERT_EQUAL("07:05:30"s, (TimeSpan::fromHours(7.0) + TimeSpan::fromMinutes(5.5)).toString());
    CPPUNIT_ASSERT_EQUAL("-5 s"s, TimeSpan::fromSeconds(-5.0).toString(TimeSpanOutputFormat::WithMeasures, false));
    CPPUNIT_ASSERT_EQUAL("0 s"s, TimeSpan().toString(TimeSpanOutputFormat::WithMeasures, false));
    CPPUNIT_ASSERT_EQUAL("5e+02 µs"s, TimeSpan::fromMilliseconds(0.5).toString(TimeSpanOutputFormat::WithMeasures, false));

    // test accuracy (of 100 nanoseconds)
    const auto test2 = TimeSpan::fromString("15.985077682");
    CPPUNIT_ASSERT_EQUAL(15.9850776, test2.totalSeconds());
    CPPUNIT_ASSERT_EQUAL(15, test2.seconds());
    CPPUNIT_ASSERT_EQUAL(985, test2.milliseconds());
    CPPUNIT_ASSERT_EQUAL(77, test2.microseconds());
    CPPUNIT_ASSERT_EQUAL(600, test2.nanoseconds());
    CPPUNIT_ASSERT_EQUAL("00:00:15.9850776"s, test2.toString());
    CPPUNIT_ASSERT_EQUAL("15 s 985 ms 77 µs 600 ns"s, test2.toString(TimeSpanOutputFormat::WithMeasures));
    CPPUNIT_ASSERT_EQUAL("15.9850776"s, test2.toString(TimeSpanOutputFormat::TotalSeconds));
}

/*!
 * \brief Tests operators of DateTime / TimeSpan.
 */
void ChronoTests::testOperators()
{
    auto dateTime = DateTime::fromDateAndTime(1999, 1, 5, 4, 16);
    CPPUNIT_ASSERT_EQUAL(7, (dateTime + TimeSpan::fromDays(2.0)).day());
    CPPUNIT_ASSERT_EQUAL(6, (dateTime + TimeSpan::fromHours(24.0)).day());
    CPPUNIT_ASSERT_EQUAL(3, (dateTime + TimeSpan::fromHours(24.0) + TimeSpan::fromHours(-1.0)).hour());
    CPPUNIT_ASSERT_EQUAL(17, (dateTime + TimeSpan::fromHours(24.0) - TimeSpan::fromMinutes(-1.0)).minute());
    dateTime += TimeSpan::fromDays(365.0);
    CPPUNIT_ASSERT_EQUAL(2000, dateTime.year());
    CPPUNIT_ASSERT_EQUAL(5, dateTime.day());
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromDays(1.0), TimeSpan::fromHours(12.0) * 2.0);
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromHours(12.0), TimeSpan::fromDays(1.0) / 2.0);
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromDays(1.0), TimeSpan::fromHours(12.0) * TimeSpan::TickType(2));
    CPPUNIT_ASSERT_EQUAL(TimeSpan::fromHours(12.0), TimeSpan::fromDays(1.0) / TimeSpan::TickType(2));
    CPPUNIT_ASSERT_EQUAL(2.0, TimeSpan::fromDays(1.0) / TimeSpan::fromHours(12.0));
}

/*!
 * \brief Tests Period.
 */
void ChronoTests::testPeriod()
{
    const auto begin(DateTime::fromDateAndTime(1994, 7, 18, 15, 30, 21)), end(DateTime::fromDateAndTime(2017, 12, 2, 15, 30, 21));
    const Period period(begin, end);
    CPPUNIT_ASSERT_EQUAL(23, period.years());
    CPPUNIT_ASSERT_EQUAL(4, period.months());
    CPPUNIT_ASSERT_EQUAL(14, period.days());
    CPPUNIT_ASSERT_EQUAL(end.toString(), (begin + period).toString());

    const auto end2(DateTime::fromDateAndTime(2018, 1, 2, 15, 30, 21));
    const Period period2(begin, end2);
    CPPUNIT_ASSERT_EQUAL(23, period2.years());
    CPPUNIT_ASSERT_EQUAL(5, period2.months());
    CPPUNIT_ASSERT_EQUAL_MESSAGE("one more day, because December has 31 days", 15, period2.days());
    CPPUNIT_ASSERT_EQUAL(end2.toString(), (begin + period2).toString());
}

/*!
 * \brief Tests hashing DateTime / TimeSpan by using in a set.
 */
void ChronoTests::testHashing()
{
    set<DateTime> dateTimes;
    dateTimes.emplace(DateTime::fromDate(2500, 2, 1));
    dateTimes.emplace(DateTime::fromDate(2500, 2, 2));
    dateTimes.emplace(DateTime::fromDate(2500, 2, 1));
    CPPUNIT_ASSERT_EQUAL(2_st, dateTimes.size());

    set<TimeSpan> timeSpans;
    timeSpans.emplace(TimeSpan::fromDays(5.0));
    timeSpans.emplace(TimeSpan::fromDays(10.0));
    timeSpans.emplace(TimeSpan::fromDays(5.0));
    CPPUNIT_ASSERT_EQUAL(2_st, timeSpans.size());
}