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    Licensed to the Apache Software Foundation (ASF) under one or more
    contributor license agreements.  See the NOTICE file distributed with
    this work for additional information regarding copyright ownership.
    The ASF licenses this file to You under the Apache License, Version 2.0
    (the "License"); you may not use this file except in compliance with
    the License.  You may obtain a copy of the License at

         http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
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}}
package {{invokerPackage}};

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonTokenId;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.datatype.threetenbp.DateTimeUtils;
import com.fasterxml.jackson.datatype.threetenbp.DecimalUtils;
import com.fasterxml.jackson.datatype.threetenbp.deser.ThreeTenDateTimeDeserializerBase;
import com.fasterxml.jackson.datatype.threetenbp.function.BiFunction;
import com.fasterxml.jackson.datatype.threetenbp.function.Function;
import org.threeten.bp.DateTimeException;
import org.threeten.bp.Instant;
import org.threeten.bp.OffsetDateTime;
import org.threeten.bp.ZoneId;
import org.threeten.bp.ZonedDateTime;
import org.threeten.bp.format.DateTimeFormatter;
import org.threeten.bp.temporal.Temporal;
import org.threeten.bp.temporal.TemporalAccessor;

import java.io.IOException;
import java.math.BigDecimal;

/**
 * Deserializer for ThreeTen temporal {@link Instant}s, {@link OffsetDateTime}, and {@link ZonedDateTime}s.
 * Adapted from the jackson threetenbp InstantDeserializer to add support for deserializing rfc822 format.
 *
 * @author Nick Williams
 */
public class CustomInstantDeserializer<T extends Temporal>
    extends ThreeTenDateTimeDeserializerBase<T> {
  private static final long serialVersionUID = 1L;

  public static final CustomInstantDeserializer<Instant> INSTANT = new CustomInstantDeserializer<Instant>(
      Instant.class, DateTimeFormatter.ISO_INSTANT,
      new Function<TemporalAccessor, Instant>() {
        @Override
        public Instant apply(TemporalAccessor temporalAccessor) {
          return Instant.from(temporalAccessor);
        }
      },
      new Function<FromIntegerArguments, Instant>() {
        @Override
        public Instant apply(FromIntegerArguments a) {
          return Instant.ofEpochMilli(a.value);
        }
      },
      new Function<FromDecimalArguments, Instant>() {
        @Override
        public Instant apply(FromDecimalArguments a) {
          return Instant.ofEpochSecond(a.integer, a.fraction);
        }
      },
      null
  );

  public static final CustomInstantDeserializer<OffsetDateTime> OFFSET_DATE_TIME = new CustomInstantDeserializer<OffsetDateTime>(
      OffsetDateTime.class, DateTimeFormatter.ISO_OFFSET_DATE_TIME,
      new Function<TemporalAccessor, OffsetDateTime>() {
        @Override
        public OffsetDateTime apply(TemporalAccessor temporalAccessor) {
          return OffsetDateTime.from(temporalAccessor);
        }
      },
      new Function<FromIntegerArguments, OffsetDateTime>() {
        @Override
        public OffsetDateTime apply(FromIntegerArguments a) {
          return OffsetDateTime.ofInstant(Instant.ofEpochMilli(a.value), a.zoneId);
        }
      },
      new Function<FromDecimalArguments, OffsetDateTime>() {
        @Override
        public OffsetDateTime apply(FromDecimalArguments a) {
          return OffsetDateTime.ofInstant(Instant.ofEpochSecond(a.integer, a.fraction), a.zoneId);
        }
      },
      new BiFunction<OffsetDateTime, ZoneId, OffsetDateTime>() {
        @Override
        public OffsetDateTime apply(OffsetDateTime d, ZoneId z) {
          return d.withOffsetSameInstant(z.getRules().getOffset(d.toLocalDateTime()));
        }
      }
  );

  public static final CustomInstantDeserializer<ZonedDateTime> ZONED_DATE_TIME = new CustomInstantDeserializer<ZonedDateTime>(
      ZonedDateTime.class, DateTimeFormatter.ISO_ZONED_DATE_TIME,
      new Function<TemporalAccessor, ZonedDateTime>() {
        @Override
        public ZonedDateTime apply(TemporalAccessor temporalAccessor) {
          return ZonedDateTime.from(temporalAccessor);
        }
      },
      new Function<FromIntegerArguments, ZonedDateTime>() {
        @Override
        public ZonedDateTime apply(FromIntegerArguments a) {
          return ZonedDateTime.ofInstant(Instant.ofEpochMilli(a.value), a.zoneId);
        }
      },
      new Function<FromDecimalArguments, ZonedDateTime>() {
        @Override
        public ZonedDateTime apply(FromDecimalArguments a) {
          return ZonedDateTime.ofInstant(Instant.ofEpochSecond(a.integer, a.fraction), a.zoneId);
        }
      },
      new BiFunction<ZonedDateTime, ZoneId, ZonedDateTime>() {
        @Override
        public ZonedDateTime apply(ZonedDateTime zonedDateTime, ZoneId zoneId) {
          return zonedDateTime.withZoneSameInstant(zoneId);
        }
      }
  );

  protected final Function<FromIntegerArguments, T> fromMilliseconds;

  protected final Function<FromDecimalArguments, T> fromNanoseconds;

  protected final Function<TemporalAccessor, T> parsedToValue;

  protected final BiFunction<T, ZoneId, T> adjust;

  protected CustomInstantDeserializer(Class<T> supportedType,
                    DateTimeFormatter parser,
                    Function<TemporalAccessor, T> parsedToValue,
                    Function<FromIntegerArguments, T> fromMilliseconds,
                    Function<FromDecimalArguments, T> fromNanoseconds,
                    BiFunction<T, ZoneId, T> adjust) {
    super(supportedType, parser);
    this.parsedToValue = parsedToValue;
    this.fromMilliseconds = fromMilliseconds;
    this.fromNanoseconds = fromNanoseconds;
    this.adjust = adjust == null ? new BiFunction<T, ZoneId, T>() {
      @Override
      public T apply(T t, ZoneId zoneId) {
        return t;
      }
    } : adjust;
  }

  @SuppressWarnings("unchecked")
  protected CustomInstantDeserializer(CustomInstantDeserializer<T> base, DateTimeFormatter f) {
    super((Class<T>) base.handledType(), f);
    parsedToValue = base.parsedToValue;
    fromMilliseconds = base.fromMilliseconds;
    fromNanoseconds = base.fromNanoseconds;
    adjust = base.adjust;
  }

  @Override
  protected JsonDeserializer<T> withDateFormat(DateTimeFormatter dtf) {
    if (dtf == _formatter) {
      return this;
    }
    return new CustomInstantDeserializer<T>(this, dtf);
  }

  @Override
  public T deserialize(JsonParser parser, DeserializationContext context) throws IOException {
    //NOTE: Timestamps contain no timezone info, and are always in configured TZ. Only
    //string values have to be adjusted to the configured TZ.
    switch (parser.getCurrentTokenId()) {
      case JsonTokenId.ID_NUMBER_FLOAT: {
        BigDecimal value = parser.getDecimalValue();
        long seconds = value.longValue();
        int nanoseconds = DecimalUtils.extractNanosecondDecimal(value, seconds);
        return fromNanoseconds.apply(new FromDecimalArguments(
            seconds, nanoseconds, getZone(context)));
      }

      case JsonTokenId.ID_NUMBER_INT: {
        long timestamp = parser.getLongValue();
        if (context.isEnabled(DeserializationFeature.READ_DATE_TIMESTAMPS_AS_NANOSECONDS)) {
          return this.fromNanoseconds.apply(new FromDecimalArguments(
              timestamp, 0, this.getZone(context)
          ));
        }
        return this.fromMilliseconds.apply(new FromIntegerArguments(
            timestamp, this.getZone(context)
        ));
      }

      case JsonTokenId.ID_STRING: {
        String string = parser.getText().trim();
        if (string.length() == 0) {
          return null;
        }
        if (string.endsWith("+0000")) {
          string = string.substring(0, string.length() - 5) + "Z";
        }
        T value;
        try {
          TemporalAccessor acc = _formatter.parse(string);
          value = parsedToValue.apply(acc);
          if (context.isEnabled(DeserializationFeature.ADJUST_DATES_TO_CONTEXT_TIME_ZONE)) {
            return adjust.apply(value, this.getZone(context));
          }
        } catch (DateTimeException e) {
          throw _peelDTE(e);
        }
        return value;
      }
    }
    throw context.mappingException("Expected type float, integer, or string.");
  }

  private ZoneId getZone(DeserializationContext context) {
    // Instants are always in UTC, so don't waste compute cycles
    return (_valueClass == Instant.class) ? null : DateTimeUtils.timeZoneToZoneId(context.getTimeZone());
  }

  private static class FromIntegerArguments {
    public final long value;
    public final ZoneId zoneId;

    private FromIntegerArguments(long value, ZoneId zoneId) {
      this.value = value;
      this.zoneId = zoneId;
    }
  }

  private static class FromDecimalArguments {
    public final long integer;
    public final int fraction;
    public final ZoneId zoneId;

    private FromDecimalArguments(long integer, int fraction, ZoneId zoneId) {
      this.integer = integer;
      this.fraction = fraction;
      this.zoneId = zoneId;
    }
  }
}
