text: /**
   * @copyright (c) 2016, Philipp Thürwächter & Pattrick Hüper
   * @copyright (c) 2007-present, Stephen Colebourne & Michael Nascimento Santos
   * @license BSD-3-Clause (see LICENSE in the root directory of this source tree)
   */
  
  import {requireNonNull, requireInstance} from './assert';
  import {DateTimeException, UnsupportedTemporalTypeException} from './errors';
  
  import {Clock} from './Clock';
  import {LocalTime} from './LocalTime';
  import {ZonedDateTime} from './ZonedDateTime';
  import {MathUtil} from './MathUtil';
  import {OffsetDateTime} from './OffsetDateTime';
  
  import {Temporal} from './temporal/Temporal';
  import {ChronoField} from './temporal/ChronoField';
  import {ChronoUnit} from './temporal/ChronoUnit';
  import {TemporalQueries} from './temporal/TemporalQueries';
  import {TemporalUnit} from './temporal/TemporalUnit';
  import {createTemporalQuery} from './temporal/TemporalQuery';
  import {DateTimeFormatter} from './format/DateTimeFormatter';
  
  const NANOS_PER_MILLI = 1000000;
  
  /**
   * An instantaneous point on the time-line.
   *
   * This class models a single instantaneous point on the time-line.
   * This might be used to record event time-stamps in the application.
   *
   * Time-scale
   *
   * The length of the solar day is the standard way that humans measure time.
   * This has traditionally been subdivided into 24 hours of 60 minutes of 60 seconds,
   * forming a 86400 second day.
   *
   * Modern timekeeping is based on atomic clocks which precisely define an SI second
   * relative to the transitions of a Caesium atom. The length of an SI second was defined
   * to be very close to the 86400th fraction of a day.
   *
   * Unfortunately, as the Earth rotates the length of the day varies.
   * In addition, over time the average length of the day is getting longer as the Earth slows.
   * As a result, the length of a solar day in 2012 is slightly longer than 86400 SI seconds.
   * The actual length of any given day and the amount by which the Earth is slowing
   * are not predictable and can only be determined by measurement.
   * The UT1 time-scale captures the accurate length of day, but is only available some
   * time after the day has completed.
   *
   * The UTC time-scale is a standard approach to bundle up all the additional fractions
   * of a second from UT1 into whole seconds, known as *leap-seconds*.
   * A leap-second may be added or removed depending on the Earth's rotational changes.
   * As such, UTC permits a day to have 86399 SI seconds or 86401 SI seconds where
   * necessary in order to keep the day aligned with the Sun.
   *
   * The modern UTC time-scale was introduced in 1972, introducing the concept of whole leap-seconds.
   * Between 1958 and 1972, the definition of UTC was complex, with minor sub-second leaps and
   * alterations to the length of the notional second. As of 2012, discussions are underway
   * to change the definition of UTC again, with the potential to remove leap seconds or
   * introduce other changes.
   *
   * Given the complexity of accurate timekeeping described above, this Java API defines
   * its own time-scale, the *Java Time-Scale*.
   *
   * The Java Time-Scale divides each calendar day into exactly 86400
   * subdivisions, known as seconds.  These seconds may differ from the
   * SI second.  It closely matches the de facto international civil time
   * scale, the definition of which changes from time to time.
   *
   * The Java Time-Scale has slightly different definitions for different
   * segments of the time-line, each based on the consensus international
   * time scale that is used as the basis for civil time. Whenever the
   * internationally-agreed time scale is modified or replaced, a new
   * segment of the Java Time-Scale must be defined for it.  Each segment
   * must meet these requirements:
   *
   * * the Java Time-Scale shall closely match the underlying international
   *   civil time scale;
   * * the Java Time-Scale shall exactly match the international civil
   *   time scale at noon each day;
   * * the Java Time-Scale shall have a precisely-defined relationship to
   *   the international civil time scale.
   *
   * There are currently, as of 2013, two segments in the Java time-scale.
   *
   * For the segment from 1972-11-03 (exact boundary discussed below) until
   * further notice, the consensus international time scale is UTC (with
   * leap seconds).  In this segment, the Java Time-Scale is identical to
   * [UTC-SLS](http://www.cl.cam.ac.uk/~mgk25/time/utc-sls/).
   * This is identical to UTC on days that do not have a leap second.
   * On days that do have a leap second, the leap second is spread equally
   * over the last 1000 seconds of the day, maintaining the appearance of
   * exactly 86400 seconds per day.
   *
   * For the segment prior to 1972-11-03, extending back arbitrarily far,
   * the consensus international time scale is defined to be UT1, applied
   * proleptically, which is equivalent to the (mean) solar time on the
   * prime meridian (Greenwich). In this segment, the Java Time-Scale is
   * identical to the consensus international time scale. The exact
   * boundary between the two segments is the instant where UT1 = UTC
   * between 1972-11-03T00:00 and 1972-11-04T12:00.
   *
   * Implementations of the Java time-scale using the JSR-310 API are not
   * required to provide any clock that is sub-second accurate, or that
   * progresses monotonically or smoothly. Implementations are therefore
   * not required to actually perform the UTC-SLS slew or to otherwise be
   * aware of leap seconds. JSR-310 does, however, require that
   * implementations must document the approach they use when defining a
   * clock representing the current instant.
   * See {@link Clock} for details on the available clocks.
   *
   * The Java time-scale is used for all date-time classes.
   * This includes {@link Instant}, {@link LocalDate}, {@link LocalTime}, {@link OffsetDateTime},
   * {@link ZonedDateTime} and {@link Duration}.
   *
   * ### Static properties of Class {@link Instant}
   *
   * Instant.EPOCH
   *
   * Instant.MIN
   *
   * Instant.MAX
   *
   * Instant.MIN_SECONDS
   *
   * Instant.MAX_SECONDS
   *
   */
  export class Instant extends Temporal {
  
      /**
       * Obtains the current instant from the system clock, or if specified
       * the current instant from the specified clock.
       *
       * This will query the specified clock to obtain the current time.
       *
       * @param {Clock} [clock=Clock.systemUTC()] - the clock to use, defaults to the system clock
       * @return {Instant} the current instant, not null
       */
      static now(clock = Clock.systemUTC()){
          return clock.instant();
      }
  
      /**
       * Obtains an instance of {@link Instant} using seconds from the
       * epoch of 1970-01-01T00:00:00Z.
       *
       * @param {number} epochSecond - the number of seconds from 1970-01-01T00:00:00Z
       * @param {number} nanoAdjustment nanoseconds start from the start of epochSecond, if null the nanosecond field is set to zero.
       * @return {Instant} an instant, not null
       * @throws DateTimeException if the instant exceeds the maximum or minimum instant
       */
      static ofEpochSecond(epochSecond, nanoAdjustment=0){
          const secs = epochSecond + MathUtil.floorDiv(nanoAdjustment, LocalTime.NANOS_PER_SECOND);
          const nos = MathUtil.floorMod(nanoAdjustment, LocalTime.NANOS_PER_SECOND);
          return Instant._create(secs, nos);
      }
  
      /**
       * Obtains an instance of {@link Instant} using milliseconds from the
       * epoch of 1970-01-01T00:00:00Z.
       *
       * The seconds and nanoseconds are extracted from the specified milliseconds.
       *
       * @param {number} epochMilli - the number of milliseconds from 1970-01-01T00:00:00Z
       * @return {Instant} an instant, not null
       * @throws DateTimeException if the instant exceeds the maximum or minimum instant
       */
      static ofEpochMilli(epochMilli) {
          const secs = MathUtil.floorDiv(epochMilli, 1000);
          const mos = MathUtil.floorMod(epochMilli, 1000);
          return Instant._create(secs, mos * 1000000);
      }
  
      /**
       * Obtains an instance of {@link Instant} from a temporal object.
       *
       * A {@link TemporalAccessor} represents some form of date and time information.
       * This factory converts the arbitrary temporal object to an instance of {@link Instant}.
       *
       * The conversion extracts the {@link ChronoField#INSTANT_SECONDS}
       * and {@link ChronoField#NANO_OF_SECOND} fields.
       *
       * This method matches the signature of the functional interface {@link TemporalQuery}
       * allowing it to be used as a query via method reference, {@link Instant::from}.
       *
       * @param {TemporalAccessor} temporal - the temporal object to convert, not null
       * @return {Instant} the instant, not null
       * @throws DateTimeException if unable to convert to an {@link Instant}
       */
      static from(temporal) {
          try {
              const instantSecs = temporal.getLong(ChronoField.INSTANT_SECONDS);
              const nanoOfSecond = temporal.get(ChronoField.NANO_OF_SECOND);
              return Instant.ofEpochSecond(instantSecs, nanoOfSecond);
          } catch (ex) {
              throw new DateTimeException('Unable to obtain Instant from TemporalAccessor: ' +
                      temporal + ', type ' + typeof temporal, ex);
          }
      }
  
      /**
       * Obtains an instance of {@link Instant} from a text string such as
       * `2007-12-03T10:15:30.000Z`.
       *
       * The string must represent a valid instant in UTC and is parsed using
       * {@link DateTimeFormatter#ISO_INSTANT}.
       *
       * @param {string} text - the text to parse, not null
       * @return {Instant} the parsed instant, not null
       * @throws DateTimeParseException if the text cannot be parsed
       */
      static parse(text) {
          return DateTimeFormatter.ISO_INSTANT.parse(text, Instant.FROM);
      }
  
      /**
       *
       * @param {number} seconds
       * @param {number} nanoOfSecond
       * @returns {Instant}
       * @private
       */
      static _create(seconds, nanoOfSecond){
          if(seconds === 0 && nanoOfSecond === 0){
              return Instant.EPOCH;
          }
          return new Instant(seconds, nanoOfSecond);
      }
  
      /**
       *
       * @param {number} seconds
       * @param {number} nanoOfSecond
       * @private
       */
      static _validate(seconds, nanoOfSecond){
          if (seconds < Instant.MIN_SECONDS || seconds > Instant.MAX_SECONDS) {
              throw new DateTimeException('Instant exceeds minimum or maximum instant');
          }
          if (nanoOfSecond < 0 || nanoOfSecond > LocalTime.NANOS_PER_SECOND) {
              throw new DateTimeException('Instant exceeds minimum or maximum instant');
          }
      }
  
      /**
       *
       * @param {number} seconds
       * @param {number} nanoOfSecond
       * @private
       */
      constructor(seconds, nanoOfSecond){
          super();
          Instant._validate(seconds, nanoOfSecond);
          this._seconds = MathUtil.safeToInt(seconds);
          this._nanos = MathUtil.safeToInt(nanoOfSecond);
      }
  
      /**
       * Checks if the specified field is supported.
       *
       * This checks if this instant can be queried for the specified field.
       * If false, then calling {@link range} and {@link get} will throw an exception.
       *
       * If the field is a {@link ChronoField} then the query is implemented here.
       * The supported fields are:
       *
       * * {@link NANO_OF_SECOND}
       * * {@link MICRO_OF_SECOND}
       * * {@link MILLI_OF_SECOND}
       * * {@link INSTANT_SECONDS}
       *
       * All other {@link ChronoField} instances will return false.
       *
       * If the field is not a {@link ChronoField}, then the result of this method
       * is obtained by invoking {@link TemporalField.isSupportedBy}
       * passing `this` as the argument.
       * Whether the field is supported is determined by the field.
       *
       * @param {TemporalField|TemporalUnit} fieldOrUnit - the field to check, null returns false
       * @return {boolean} true if the field is supported on this instant, false if not
       */
      isSupported(fieldOrUnit) {
          if (fieldOrUnit instanceof ChronoField) {
              return fieldOrUnit === ChronoField.INSTANT_SECONDS || fieldOrUnit === ChronoField.NANO_OF_SECOND || fieldOrUnit === ChronoField.MICRO_OF_SECOND || fieldOrUnit === ChronoField.MILLI_OF_SECOND;
          }
          if (fieldOrUnit instanceof ChronoUnit) {
              return fieldOrUnit.isTimeBased() || fieldOrUnit === ChronoUnit.DAYS;
          }
          return fieldOrUnit != null && fieldOrUnit.isSupportedBy(this);
      }
  
      /**
       * Gets the range of valid values for the specified field.
       *
       * The range object expresses the minimum and maximum valid values for a field.
       * This instant is used to enhance the accuracy of the returned range.
       * If it is not possible to return the range, because the field is not supported
       * or for some other reason, an exception is thrown.
       *
       * If the field is a {@link ChronoField} then the query is implemented here.
       * The supported fields (see {@link isSupported}) will return
       * appropriate range instances.
       * All other {@link ChronoField} instances will throw a {@link DateTimeException}.
       *
       * If the field is not a {@link ChronoField}, then the result of this method
       * is obtained by invoking {@link TemporalField.rangeRefinedBy}
       * passing `this` as the argument.
       * Whether the range can be obtained is determined by the field.
       *
       * @param {TemporalField} field - the field to query the range for, not null
       * @return {ValueRange} the range of valid values for the field, not null
       * @throws DateTimeException if the range for the field cannot be obtained
       */
      range(field) {
          return super.range(field);
      }
  
      /**
       * Gets the value of the specified field from this instant as an `int`.
       *
       * This queries this instant for the value for the specified field.
       * The returned value will always be within the valid range of values for the field.
       * If it is not possible to return the value, because the field is not supported
       * or for some other reason, an exception is thrown.
       *
       * If the field is a {@link ChronoField} then the query is implemented here.
       * The supported fields (see {@link isSupported}) will return valid
       * values based on this date-time, except {@link INSTANT_SECONDS} which is too
       * large to fit in an `int` and throws a {@link DateTimeException}.
       * All other {@link ChronoField} instances will throw a {@link DateTimeException}.
       *
       * If the field is not a {@link ChronoField}, then the result of this method
       * is obtained by invoking {@link TemporalField.getFrom}
       * passing `this` as the argument. Whether the value can be obtained,
       * and what the value represents, is determined by the field.
       *
       * @param {TemporalField} field - the field to get, not null
       * @return {number} the value for the field
       * @throws DateTimeException if a value for the field cannot be obtained
       * @throws ArithmeticException if numeric overflow occurs
       */
      get(field) {
          return this.getLong(field);
      }
  
      /**
       * Gets the value of the specified field from this instant as a `long`.
       *
       * This queries this instant for the value for the specified field.
       * If it is not possible to return the value, because the field is not supported
       * or for some other reason, an exception is thrown.
       *
       * If the field is a {@link ChronoField} then the query is implemented here.
       * The supported fields (see {@link isSupported}) will return valid
       * values based on this date-time.
       * All other {@link ChronoField} instances will throw a {@link DateTimeException}.
       *
       * If the field is not a {@link ChronoField}, then the result of this method
       * is obtained by invoking {@link TemporalField.getFrom}
       * passing `this` as the argument. Whether the value can be obtained,
       * and what the value represents, is determined by the field.
       *
       * @param {TemporalField} field - the field to get, not null
       * @return {number} the value for the field
       * @throws DateTimeException if a value for the field cannot be obtained
       * @throws ArithmeticException if numeric overflow occurs
       */
      getLong(field) {
          if (field instanceof ChronoField) {
              switch (field) {
                  case ChronoField.NANO_OF_SECOND: return this._nanos;
                  case ChronoField.MICRO_OF_SECOND: return MathUtil.intDiv(this._nanos, 1000);
                  case ChronoField.MILLI_OF_SECOND: return MathUtil.intDiv(this._nanos, NANOS_PER_MILLI);
                  case ChronoField.INSTANT_SECONDS: return this._seconds;
              }
              throw new UnsupportedTemporalTypeException('Unsupported field: ' + field);
          }
          return field.getFrom(this);
      }
  
      /**
       * Gets the number of seconds from the Java epoch of 1970-01-01T00:00:00Z.
       *
       * The epoch second count is a simple incrementing count of seconds where
       * second 0 is 1970-01-01T00:00:00Z.
       * The nanosecond part of the day is returned by {@link getNanosOfSecond}.
       *
       * @return {number} the seconds from the epoch of 1970-01-01T00:00:00Z
       */
      epochSecond(){
          return this._seconds;
      }
  
      /**
       * Gets the number of nanoseconds, later along the time-line, from the start
       * of the second.
       *
       * The nanosecond-of-second value measures the total number of nanoseconds from
       * the second returned by {@link getEpochSecond}.
       *
       * @return {number} the nanoseconds within the second, always positive, never exceeds 999,999,999
       */
      nano(){
          return this._nanos;
      }
  
      //-------------------------------------------------------------------------
      /**
       * Returns an adjusted copy of this instant.
       *
       * This returns a new {@link Instant}, based on this one, with the date adjusted.
       * The adjustment takes place using the specified adjuster strategy object.
       * Read the documentation of the adjuster to understand what adjustment will be made.
       *
       * The result of this method is obtained by invoking the
       * {@link TemporalAdjuster#adjustInto} method on the
       * specified adjuster passing `this` as the argument.
       *
       * This instance is immutable and unaffected by this method call.
       *
       * @param {!TemporalAdjuster} adjuster - the adjuster to use, not null
       * @return {Instant} an {@link Instant} based on `this` with the adjustment made, not null
       * @throws DateTimeException if the adjustment cannot be made
       * @throws ArithmeticException if numeric overflow occurs
       */
      withAdjuster(adjuster) {
          requireNonNull(adjuster, 'adjuster');
          return adjuster.adjustInto(this);
      }
  
      /**
       * Returns a copy of this instant with the specified field set to a new value.
       *
       * This returns a new {@link Instant}, based on this one, with the value
       * for the specified field changed.
       * If it is not possible to set the value, because the field is not supported or for
       * some other reason, an exception is thrown.
       *
       * If the field is a {@link ChronoField} then the adjustment is implemented here.
       * The supported fields behave as follows:
       *
       * * {@link NANO_OF_SECOND} -
       *  Returns an {@link Instant} with the specified nano-of-second.
       *  The epoch-second will be unchanged.
       * * {@link MICRO_OF_SECOND} -
       *  Returns an {@link Instant} with the nano-of-second replaced by the specified
       *  micro-of-second multiplied by 1,000. The epoch-second will be unchanged.
       * * {@link MILLI_OF_SECOND} -
       *  Returns an {@link Instant} with the nano-of-second replaced by the specified
       *  milli-of-second multiplied by 1,000,000. The epoch-second will be unchanged.
       * * {@link INSTANT_SECONDS} -
       *  Returns an {@link Instant} with the specified epoch-second.
       *  The nano-of-second will be unchanged.
       *
       *
       * In all cases, if the new value is outside the valid range of values for the field
       * then a {@link DateTimeException} will be thrown.
       *
       * All other {@link ChronoField} instances will throw a {@link DateTimeException}.
       *
       * If the field is not a {@link ChronoField}, then the result of this method
       * is obtained by invoking {@link TemporalField.adjustInto}
       * passing `this` as the argument. In this case, the field determines
       * whether and how to adjust the instant.
       *
       * This instance is immutable and unaffected by this method call.
       *
       * @param {TemporalField} field - the field to set in the result, not null
       * @param {number} newValue - the new value of the field in the result
       * @return {Instant} an {@link Instant} based on `this` with the specified field set, not null
       * @throws DateTimeException if the field cannot be set
       * @throws ArithmeticException if numeric overflow occurs
       */
      withFieldValue(field, newValue) {
          requireNonNull(field, 'field');
          if (field instanceof ChronoField) {
              field.checkValidValue(newValue);
              switch (field) {
                  case ChronoField.MILLI_OF_SECOND: {
                      const nval = newValue * NANOS_PER_MILLI;
                      return (nval !== this._nanos? Instant._create(this._seconds, nval) : this);
                  }
                  case ChronoField.MICRO_OF_SECOND: {
                      const nval = newValue * 1000;
                      return (nval !== this._nanos? Instant._create(this._seconds, nval) : this);
                  }
                  case ChronoField.NANO_OF_SECOND: return (newValue !== this._nanos? Instant._create(this._seconds, newValue) : this);
                  case ChronoField.INSTANT_SECONDS: return (newValue !== this._seconds ? Instant._create(newValue, this._nanos) : this);
              }
              throw new UnsupportedTemporalTypeException('Unsupported field: ' + field);
          }
          return field.adjustInto(this, newValue);
      }
  
      //-----------------------------------------------------------------------
      /**
       * Returns a copy of this {@link Instant} truncated to the specified unit.
       *
       * Truncating the instant returns a copy of the original with fields
       * smaller than the specified unit set to zero.
       * The fields are calculated on the basis of using a UTC offset as seen
       * in {@link toString}.
       * For example, truncating with {@link ChronoUnit#MINUTES} will
       * round down to the nearest minute, setting the seconds and nanoseconds to zero.
       *
       * The unit must have a duration (see {@link TemporalUnit#getDuration})
       * that divides into the length of a standard day without remainder.
       * This includes all supplied time units on {@link ChronoUnit} and
       * {@link ChronoUnit#DAYS}. Other units throw an exception.
       *
       * This instance is immutable and unaffected by this method call.
       *
       * @param {!TemporalUnit} unit - the unit to truncate to, not null
       * @return {Instant} an {@link Instant} based on this instant with the time truncated, not null
       * @throws DateTimeException if the unit is invalid for truncation
       */
      truncatedTo(unit) {
          requireNonNull(unit, 'unit');
          if (unit === ChronoUnit.NANOS) {
              return this;
          }
          const unitDur = unit.duration();
          if (unitDur.seconds() > LocalTime.SECONDS_PER_DAY) {
              throw new DateTimeException('Unit is too large to be used for truncation');
          }
          const dur = unitDur.toNanos();
          if (MathUtil.intMod(LocalTime.NANOS_PER_DAY, dur) !== 0) {
              throw new DateTimeException('Unit must divide into a standard day without remainder');
          }
          const nod = MathUtil.intMod(this._seconds, LocalTime.SECONDS_PER_DAY) * LocalTime.NANOS_PER_SECOND + this._nanos;
          const result = MathUtil.intDiv(nod, dur) * dur;
          return this.plusNanos(result - nod);
      }
  
      //-----------------------------------------------------------------------
  
      /**
       * @param {!TemporalAmount} amount
       * @return {Instant}
       * @throws DateTimeException
       * @throws ArithmeticException
       */
      plusAmount(amount) {
          requireNonNull(amount, 'amount');
          return amount.addTo(this);
      }
  
      /**
       * @param {!number} amountToAdd
       * @param {!TemporalUnit} unit
       * @return {Instant}
       * @throws DateTimeException
       * @throws ArithmeticException
       */
      plusAmountUnit(amountToAdd, unit) {
          requireNonNull(amountToAdd, 'amountToAdd');
          requireNonNull(unit, 'unit');
          requireInstance(unit, TemporalUnit);
          if (unit instanceof ChronoUnit) {
              switch (unit) {
                  case ChronoUnit.NANOS: return this.plusNanos(amountToAdd);
                  case ChronoUnit.MICROS: return this._plus(MathUtil.intDiv(amountToAdd, 1000000), MathUtil.intMod(amountToAdd, 1000000) * 1000);
                  case ChronoUnit.MILLIS: return this.plusMillis(amountToAdd);
                  case ChronoUnit.SECONDS: return this.plusSeconds(amountToAdd);
                  case ChronoUnit.MINUTES: return this.plusSeconds(MathUtil.safeMultiply(amountToAdd, LocalTime.SECONDS_PER_MINUTE));
                  case ChronoUnit.HOURS: return this.plusSeconds(MathUtil.safeMultiply(amountToAdd, LocalTime.SECONDS_PER_HOUR));
                  case ChronoUnit.HALF_DAYS: return this.plusSeconds(MathUtil.safeMultiply(amountToAdd, LocalTime.SECONDS_PER_DAY / 2));
                  case ChronoUnit.DAYS: return this.plusSeconds(MathUtil.safeMultiply(amountToAdd, LocalTime.SECONDS_PER_DAY));
              }
              throw new UnsupportedTemporalTypeException('Unsupported unit: ' + unit);
          }
          return unit.addTo(this, amountToAdd);
      }
  
      /**
       * Returns a copy of this instant with the specified duration in seconds added.
       *
       * This instance is immutable and unaffected by this method call.
       *
       * @param {number} secondsToAdd  the seconds to add, positive or negative
       * @return {Instant} an {@link Instant} based on this instant with the specified seconds added, not null
       * @throws DateTimeException if the result exceeds the maximum or minimum instant
       */
      plusSeconds(secondsToAdd) {
          return this._plus(secondsToAdd, 0);
      }
  
      /**
       * Returns a copy of this instant with the specified duration in milliseconds added.
       *
       * This instance is immutable and unaffected by this method call.
       *
       * @param {number} millisToAdd - the milliseconds to add, positive or negative
       * @return {Instant} an {@link Instant} based on this instant with the specified milliseconds added, not null
       * @throws DateTimeException if the result exceeds the maximum or minimum instant
       * @throws ArithmeticException if numeric overflow occurs
       */
      plusMillis(millisToAdd) {
          return this._plus(MathUtil.intDiv(millisToAdd, 1000), MathUtil.intMod(millisToAdd, 1000) * NANOS_PER_MILLI);
      }
  
      /**
       * Returns a copy of this instant with the specified duration in nanoseconds added.
       *
       * This instance is immutable and unaffected by this method call.
       *
       * @param {number} nanosToAdd - the nanoseconds to add, positive or negative
       * @return {Instant} an {@link Instant} based on this instant with the specified nanoseconds added, not null
       * @throws DateTimeException if the result exceeds the maximum or minimum instant
       */
      plusNanos(nanosToAdd) {
          return this._plus(0, nanosToAdd);
      }
  
      /**
       * Returns a copy of this instant with the specified duration added.
       *
       * This instance is immutable and unaffected by this method call.
       *
       * @param {number} secondsToAdd - the seconds to add, positive or negative
       * @param {number} nanosToAdd - the nanos to add, positive or negative
       * @return {Instant} an {@link Instant} based on this instant with the specified seconds added, not null
       * @throws DateTimeException if the result exceeds the maximum or minimum instant
       */
      _plus(secondsToAdd, nanosToAdd) {
          if (secondsToAdd === 0 && nanosToAdd === 0) {
              return this;
          }
          let epochSec = this._seconds + secondsToAdd;
          epochSec = epochSec + MathUtil.intDiv(nanosToAdd, LocalTime.NANOS_PER_SECOND);
          const nanoAdjustment = this._nanos + nanosToAdd % LocalTime.NANOS_PER_SECOND;
          return Instant.ofEpochSecond(epochSec, nanoAdjustment);
      }
  
      //-----------------------------------------------------------------------
  
      /**
       * @param {!TemporalAmount} amount
       * @return {Instant}
       * @throws DateTimeException
       * @throws ArithmeticException
       */
      minusAmount(amount) {
          requireNonNull(amount, 'amount');
          return amount.subtractFrom(this);
      }
  
      /**
       * @param {!number} amountToSubtract
       * @param {!TemporalUnit} unit
       * @return {Instant}
       * @throws DateTimeException
       * @throws ArithmeticException
       */
      minusAmountUnit(amountToSubtract, unit) {
          return this.plusAmountUnit(-1 * amountToSubtract, unit);
      }
  
      /**
       * Returns a copy of this instant with the specified duration in seconds subtracted.
       *
       * This instance is immutable and unaffected by this method call.
       *
       * @param {number} secondsToSubtract - the seconds to subtract, positive or negative
       * @return {Instant} an {@link Instant} based on this instant with the specified seconds subtracted, not null
       * @throws DateTimeException if the result exceeds the maximum or minimum instant
       */
      minusSeconds(secondsToSubtract) {
          return this.plusSeconds(secondsToSubtract * -1);
      }
  
      /**
       * Returns a copy of this instant with the specified duration in milliseconds subtracted.
       *
       * This instance is immutable and unaffected by this method call.
       *
       * @param {number} millisToSubtract - the milliseconds to subtract, positive or negative
       * @return {Instant} an {@link Instant} based on this instant with the specified milliseconds subtracted, not null
       * @throws DateTimeException if the result exceeds the maximum or minimum instant
       * @throws ArithmeticException if numeric overflow occurs
       */
      minusMillis(millisToSubtract) {
          return this.plusMillis(-1 * millisToSubtract);
      }
  
      /**
       * Returns a copy of this instant with the specified duration in nanoseconds subtracted.
       *
       * This instance is immutable and unaffected by this method call.
       *
       * @param {number} nanosToSubtract  the nanoseconds to subtract, positive or negative
       * @return {Instant} an {@link Instant} based on this instant with the specified nanoseconds subtracted, not null
       * @throws DateTimeException if the result exceeds the maximum or minimum instant
       * @throws ArithmeticException if numeric overflow occurs
       */
      minusNanos(nanosToSubtract) {
          return this.plusNanos(-1 * nanosToSubtract);
      }
  
      //-------------------------------------------------------------------------
      /**
       * Queries this instant using the specified query.
       *
       * This queries this instant using the specified query strategy object.
       * The {@link TemporalQuery} object defines the logic to be used to
       * obtain the result. Read the documentation of the query to understand
       * what the result of this method will be.
       *
       * The result of this method is obtained by invoking the
       * {@link TemporalQuery#queryFrom} method on the
       * specified query passing `this` as the argument.
       *
       * @param {!TemporalQuery} query - the query to invoke, not null
       * @return {*} the query result, null may be returned (defined by the query)
       * @throws DateTimeException if unable to query (defined by the query)
       * @throws ArithmeticException if numeric overflow occurs (defined by the query)
       */
      query(query) {
          requireNonNull(query, 'query');
          if (query === TemporalQueries.precision()) {
              return ChronoUnit.NANOS;
          }
          // inline TemporalAccessor.super.query(query) as an optimization
          if (query === TemporalQueries.localDate() || query === TemporalQueries.localTime() ||
                  query === TemporalQueries.chronology() || query === TemporalQueries.zoneId() ||
                  query === TemporalQueries.zone() || query === TemporalQueries.offset()) {
              return null;
          }
          return query.queryFrom(this);
      }
  
      /**
       * Adjusts the specified temporal object to have this instant.
       *
       * This returns a temporal object of the same observable type as the input
       * with the instant changed to be the same as this.
       *
       * The adjustment is equivalent to using {@link Temporal#with}
       * twice, passing {@link ChronoField#INSTANT_SECONDS} and
       * {@link ChronoField#NANO_OF_SECOND} as the fields.
       *
       * In most cases, it is clearer to reverse the calling pattern by using
       * {@link Temporal#with}:
       * <pre>
       *   // these two lines are equivalent, but the second approach is recommended
       *   temporal = thisInstant.adjustInto(temporal);
       *   temporal = temporal.with(thisInstant);
       * </pre>
       *
       * This instance is immutable and unaffected by this method call.
       *
       * @param {!Temporal} temporal - the target object to be adjusted, not null
       * @return {Temporal} the adjusted object, not null
       * @throws DateTimeException if unable to make the adjustment
       * @throws ArithmeticException if numeric overflow occurs
       */
      adjustInto(temporal) {
          requireNonNull(temporal, 'temporal');
          return temporal.with(ChronoField.INSTANT_SECONDS, this._seconds).with(ChronoField.NANO_OF_SECOND, this._nanos);
      }
  
      /**
       * Calculates the period between this instant and another instant in
       * terms of the specified unit.
       *
       * This calculates the period between two instants in terms of a single unit.
       * The start and end points are `this` and the specified instant.
       * The result will be negative if the end is before the start.
       * The calculation returns a whole number, representing the number of
       * complete units between the two instants.
       * The {@link Temporal} passed to this method is converted to a
       * {@link Instant} using {@link from}.
       * For example, the period in days between two dates can be calculated
       * using `startInstant.until(endInstant, SECONDS)`.
       *
       * This method operates in association with {@link TemporalUnit#between}.
       * The result of this method is a `long` representing the amount of
       * the specified unit. By contrast, the result of {@link between} is an
       * object that can be used directly in addition/subtraction:
       * <pre>
       *   long period = start.until(end, SECONDS);   // this method
       *   dateTime.plus(SECONDS.between(start, end));      // use in plus/minus
       * </pre>
       *
       * The calculation is implemented in this method for {@link ChronoUnit}.
       * The units {@link NANOS}, {@link MICROS}, {@link MILLIS}, {@link SECONDS},
       * {@link MINUTES}, {@link HOURS}, {@link HALF_DAYS} and {@link DAYS}
       * are supported. Other {@link ChronoUnit} values will throw an exception.
       *
       * If the unit is not a {@link ChronoUnit}, then the result of this method
       * is obtained by invoking {@link TemporalUnit.between}
       * passing `this` as the first argument and the input temporal as
       * the second argument.
       *
       * This instance is immutable and unaffected by this method call.
       *
       * @param {Temporal} endExclusive - the end date, which is converted to an {@link Instant}, not null
       * @param {TemporalUnit} unit - the unit to measure the period in, not null
       * @return {number} the amount of the period between this date and the end date
       * @throws DateTimeException if the period cannot be calculated
       * @throws ArithmeticException if numeric overflow occurs
       */
      until(endExclusive, unit) {
          requireNonNull(endExclusive, 'endExclusive');
          requireNonNull(unit, 'unit');
          const end = Instant.from(endExclusive);
          if (unit instanceof ChronoUnit) {
              switch (unit) {
                  case ChronoUnit.NANOS: return this._nanosUntil(end);
                  case ChronoUnit.MICROS: return MathUtil.intDiv(this._nanosUntil(end), 1000);
                  case ChronoUnit.MILLIS: return MathUtil.safeSubtract(end.toEpochMilli(), this.toEpochMilli());
                  case ChronoUnit.SECONDS: return this._secondsUntil(end);
                  case ChronoUnit.MINUTES: return MathUtil.intDiv(this._secondsUntil(end), LocalTime.SECONDS_PER_MINUTE);
                  case ChronoUnit.HOURS: return MathUtil.intDiv(this._secondsUntil(end), LocalTime.SECONDS_PER_HOUR);
                  case ChronoUnit.HALF_DAYS: return MathUtil.intDiv(this._secondsUntil(end), (12 * LocalTime.SECONDS_PER_HOUR));
                  case ChronoUnit.DAYS: return MathUtil.intDiv(this._secondsUntil(end), LocalTime.SECONDS_PER_DAY);
              }
              throw new UnsupportedTemporalTypeException('Unsupported unit: ' + unit);
          }
          return unit.between(this, end);
      }
  
      /**
       *
       * @param {Temporal} end
       * @returns {number}
       * @private
       */
      _nanosUntil(end) {
          const secsDiff = MathUtil.safeSubtract(end.epochSecond(), this.epochSecond());
          const totalNanos = MathUtil.safeMultiply(secsDiff, LocalTime.NANOS_PER_SECOND);
          return MathUtil.safeAdd(totalNanos, end.nano() - this.nano());
      }
  
      /**
       *
       * @param {Temporal} end
       * @returns {number}
       * @private
       */
      _secondsUntil(end) {
          let secsDiff = MathUtil.safeSubtract(end.epochSecond(), this.epochSecond());
          const nanosDiff = end.nano() - this.nano();
          if (secsDiff > 0 && nanosDiff < 0) {
              secsDiff--;
          } else if (secsDiff < 0 && nanosDiff > 0) {
              secsDiff++;
          }
          return secsDiff;
      }
  
      //-----------------------------------------------------------------------
      /**
       * Combines this instant with an offset to create an {@link OffsetDateTime}.
       *
       * This returns an {@link OffsetDateTime} formed from this instant at the
       * specified offset from UTC/Greenwich. An exception will be thrown if the
       * instant is too large to fit into an offset date-time.
       *
       * This method is equivalent to {@link OffsetDateTime#ofInstant}.
       *
       * @param {ZoneOffset} offset - the offset to combine with, not null
       * @return {OffsetDateTime} the offset date-time formed from this instant and the specified offset, not null
       * @throws DateTimeException if the result exceeds the supported range
       */
      atOffset(offset) {
          return OffsetDateTime.ofInstant(this, offset);
      }
  
      /**
       * Combines this instant with a time-zone to create a {@link ZonedDateTime}.
       *
       * This returns an {@link ZonedDateTime} formed from this instant at the
       * specified time-zone. An exception will be thrown if the instant is too
       * large to fit into a zoned date-time.
       *
       * This method is equivalent to {@link ZonedDateTime#ofInstant}.
       *
       * @param {ZoneId} zone - the zone to combine with, not null
       * @return {ZonedDateTime} the zoned date-time formed from this instant and the specified zone, not null
       * @throws DateTimeException if the result exceeds the supported range
       */
      atZone(zone) {
          return ZonedDateTime.ofInstant(this, zone);
      }
  
      //-----------------------------------------------------------------------
      /**
       * Converts this instant to the number of milliseconds from the epoch
       * of 1970-01-01T00:00:00Z.
       *
       * If this instant represents a point on the time-line too far in the future
       * or past to fit in a `long` milliseconds, then an exception is thrown.
       *
       * If this instant has greater than millisecond precision, then the conversion
       * will drop any excess precision information as though the amount in nanoseconds
       * was subject to integer division by one million.
       *
       * @return {number} the number of milliseconds since the epoch of 1970-01-01T00:00:00Z
       * @throws ArithmeticException if numeric overflow occurs
       */
      toEpochMilli() {
          const millis = MathUtil.safeMultiply(this._seconds, 1000);
          return millis + MathUtil.intDiv(this._nanos, NANOS_PER_MILLI);
      }
  
      //-----------------------------------------------------------------------
      /**
       * Compares this instant to the specified instant.
       *
       * The comparison is based on the time-line position of the instants.
       * It is "consistent with equals", as defined by {@link Comparable}.
       *
       * @param {Instant} otherInstant  the other instant to compare to, not null
       * @return {number} the comparator value, negative if less, positive if greater
       * @throws NullPointerException if otherInstant is null
       */
      compareTo(otherInstant) {
          requireNonNull(otherInstant, 'otherInstant');
          requireInstance(otherInstant, Instant, 'otherInstant');
          const cmp = MathUtil.compareNumbers(this._seconds, otherInstant._seconds);
          if (cmp !== 0) {
              return cmp;
          }
          return this._nanos - otherInstant._nanos;
      }
  
      /**
       * Checks if this instant is after the specified instant.
       *
       * The comparison is based on the time-line position of the instants.
       *
       * @param {Instant} otherInstant  the other instant to compare to, not null
       * @return {boolean} true if this instant is after the specified instant
       * @throws NullPointerException if otherInstant is null
       */
      isAfter(otherInstant) {
          return this.compareTo(otherInstant) > 0;
      }
  
      /**
       * Checks if this instant is before the specified instant.
       *
       * The comparison is based on the time-line position of the instants.
       *
       * @param {Instant} otherInstant  the other instant to compare to, not null
       * @return {boolean} true if this instant is before the specified instant
       * @throws NullPointerException if otherInstant is null
       */
      isBefore(otherInstant) {
          return this.compareTo(otherInstant) < 0;
      }
  
      /**
       * Checks if this instant is equal to the specified instant.
       *
       * The comparison is based on the time-line position of the instants.
       *
       * @param {*} other - the other instant, null/ undefined returns false
       * @return {boolean} true if the other instant is equal to this one
       */
      equals(other) {
          if(this === other){
              return true;
          }
          if(other instanceof Instant){
              return this.epochSecond() === other.epochSecond() &&
                  this.nano() === other.nano();
          }
          return false;
      }
  
      /**
       * Returns a hash code for this instant.
       *
       * @return {number} a suitable hash code
       */
      hashCode() {
          return MathUtil.hashCode(this._seconds, this._nanos);
      }
  
      /**
       * A string representation of this instant using ISO-8601 representation.
       *
       * The format used is the same as {@link DateTimeFormatter#ISO_INSTANT}.
       *
       * @return {string} an ISO-8601 representation of this instant, not null
       */
      toString(){
          return DateTimeFormatter.ISO_INSTANT.format(this);
      }
  
      /**
       *
       * @return {string} same as {@link LocalDate.toString}
       */
      toJSON() {
          return this.toString();
      }
  }
  
  export function _init() {
      Instant.MIN_SECONDS = -31619119219200; // -1000000-01-01T00:00:00Z
      Instant.MAX_SECONDS = 31494816403199; // +1000000-12-31T23:59:59.999999999Z
      Instant.EPOCH = new Instant(0, 0);
      Instant.MIN = Instant.ofEpochSecond(Instant.MIN_SECONDS, 0);
      Instant.MAX = Instant.ofEpochSecond(Instant.MAX_SECONDS, 999999999);
      Instant.FROM = createTemporalQuery('Instant.FROM', (temporal) => {
          return Instant.from(temporal);
      });
  }
  