content: /*
   * 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
   * limitations under the License.
   */
  package com.datastax.oss.driver.internal.core.type.codec;
  
  import com.datastax.oss.driver.api.core.ProtocolVersion;
  import com.datastax.oss.driver.api.core.type.DataType;
  import com.datastax.oss.driver.api.core.type.DataTypes;
  import com.datastax.oss.driver.api.core.type.codec.TypeCodec;
  import com.datastax.oss.driver.api.core.type.codec.TypeCodecs;
  import com.datastax.oss.driver.api.core.type.reflect.GenericType;
  import com.datastax.oss.driver.internal.core.util.Strings;
  import edu.umd.cs.findbugs.annotations.NonNull;
  import edu.umd.cs.findbugs.annotations.Nullable;
  import io.netty.util.concurrent.FastThreadLocal;
  import java.nio.ByteBuffer;
  import java.text.ParsePosition;
  import java.text.SimpleDateFormat;
  import java.time.Instant;
  import java.time.ZoneId;
  import java.util.Date;
  import java.util.Optional;
  import java.util.TimeZone;
  import net.jcip.annotations.ThreadSafe;
  
  /**
   * A codec that handles Apache Cassandra(R)'s timestamp type and maps it to Java's {@link Instant}.
   *
   * <p>Implementation notes:
   *
   * <ol>
   *   <li>Because {@code Instant} uses a precision of nanoseconds, whereas the timestamp type uses a
   *       precision of milliseconds, truncation will happen for any excess precision information as
   *       though the amount in nanoseconds was subject to integer division by one million.
   *   <li>For compatibility reasons, this codec uses the legacy {@link SimpleDateFormat} API
   *       internally when parsing and formatting, and converts from {@link Instant} to {@link Date}
   *       and vice versa. Specially when parsing, this may yield different results as compared to
   *       what the newer Java Time API parsers would have produced for the same input.
   *   <li>Also, {@code Instant} can store points on the time-line further in the future and further
   *       in the past than {@code Date}. This codec will throw an exception when attempting to parse
   *       or format an {@code Instant} falling in this category.
   * </ol>
   *
   * <h3>Accepted date-time formats</h3>
   *
   * The following patterns are valid CQL timestamp literal formats for Apache Cassandra(R) 3.0 and
   * higher, and are thus all recognized when parsing:
   *
   * <ol>
   *   <li>{@code yyyy-MM-dd'T'HH:mm}
   *   <li>{@code yyyy-MM-dd'T'HH:mm:ss}
   *   <li>{@code yyyy-MM-dd'T'HH:mm:ss.SSS}
   *   <li>{@code yyyy-MM-dd'T'HH:mmX}
   *   <li>{@code yyyy-MM-dd'T'HH:mmXX}
   *   <li>{@code yyyy-MM-dd'T'HH:mmXXX}
   *   <li>{@code yyyy-MM-dd'T'HH:mm:ssX}
   *   <li>{@code yyyy-MM-dd'T'HH:mm:ssXX}
   *   <li>{@code yyyy-MM-dd'T'HH:mm:ssXXX}
   *   <li>{@code yyyy-MM-dd'T'HH:mm:ss.SSSX}
   *   <li>{@code yyyy-MM-dd'T'HH:mm:ss.SSSXX}
   *   <li>{@code yyyy-MM-dd'T'HH:mm:ss.SSSXXX}
   *   <li>{@code yyyy-MM-dd'T'HH:mm z}
   *   <li>{@code yyyy-MM-dd'T'HH:mm:ss z}
   *   <li>{@code yyyy-MM-dd'T'HH:mm:ss.SSS z}
   *   <li>{@code yyyy-MM-dd HH:mm}
   *   <li>{@code yyyy-MM-dd HH:mm:ss}
   *   <li>{@code yyyy-MM-dd HH:mm:ss.SSS}
   *   <li>{@code yyyy-MM-dd HH:mmX}
   *   <li>{@code yyyy-MM-dd HH:mmXX}
   *   <li>{@code yyyy-MM-dd HH:mmXXX}
   *   <li>{@code yyyy-MM-dd HH:mm:ssX}
   *   <li>{@code yyyy-MM-dd HH:mm:ssXX}
   *   <li>{@code yyyy-MM-dd HH:mm:ssXXX}
   *   <li>{@code yyyy-MM-dd HH:mm:ss.SSSX}
   *   <li>{@code yyyy-MM-dd HH:mm:ss.SSSXX}
   *   <li>{@code yyyy-MM-dd HH:mm:ss.SSSXXX}
   *   <li>{@code yyyy-MM-dd HH:mm z}
   *   <li>{@code yyyy-MM-dd HH:mm:ss z}
   *   <li>{@code yyyy-MM-dd HH:mm:ss.SSS z}
   *   <li>{@code yyyy-MM-dd}
   *   <li>{@code yyyy-MM-ddX}
   *   <li>{@code yyyy-MM-ddXX}
   *   <li>{@code yyyy-MM-ddXXX}
   *   <li>{@code yyyy-MM-dd z}
   * </ol>
   *
   * By default, when parsing, timestamp literals that do not include any time zone information will
   * be interpreted using the system's {@linkplain ZoneId#systemDefault() default time zone}. This is
   * intended to mimic Apache Cassandra(R)'s own parsing behavior (see {@code
   * org.apache.cassandra.serializers.TimestampSerializer}). The default time zone can be modified
   * using the {@linkplain TimestampCodec#TimestampCodec(ZoneId) one-arg constructor} that takes a
   * custom {@link ZoneId} as an argument.
   *
   * <p>When formatting, the pattern used is always {@code yyyy-MM-dd'T'HH:mm:ss.SSSXXX} and the time
   * zone is either the the system's default one, or the one that was provided when instantiating the
   * codec.
   */
  @ThreadSafe
  public class TimestampCodec implements TypeCodec<Instant> {
  
    /**
     * Patterns accepted by Apache Cassandra(R) 3.0 and higher when parsing CQL literals.
     *
     * <p>Note that Cassandra's TimestampSerializer declares many more patterns but some of them are
     * equivalent when parsing.
     */
    private static final String[] DATE_STRING_PATTERNS =
        new String[] {
          // 1) date-time patterns separated by 'T'
          // (declared first because none of the others are ISO compliant, but some of these are)
          // 1.a) without time zone
          "yyyy-MM-dd'T'HH:mm",
          "yyyy-MM-dd'T'HH:mm:ss",
          "yyyy-MM-dd'T'HH:mm:ss.SSS",
          // 1.b) with ISO-8601 time zone
          "yyyy-MM-dd'T'HH:mmX",
          "yyyy-MM-dd'T'HH:mmXX",
          "yyyy-MM-dd'T'HH:mmXXX",
          "yyyy-MM-dd'T'HH:mm:ssX",
          "yyyy-MM-dd'T'HH:mm:ssXX",
          "yyyy-MM-dd'T'HH:mm:ssXXX",
          "yyyy-MM-dd'T'HH:mm:ss.SSSX",
          "yyyy-MM-dd'T'HH:mm:ss.SSSXX",
          "yyyy-MM-dd'T'HH:mm:ss.SSSXXX",
          // 1.c) with generic time zone
          "yyyy-MM-dd'T'HH:mm z",
          "yyyy-MM-dd'T'HH:mm:ss z",
          "yyyy-MM-dd'T'HH:mm:ss.SSS z",
          // 2) date-time patterns separated by whitespace
          // 2.a) without time zone
          "yyyy-MM-dd HH:mm",
          "yyyy-MM-dd HH:mm:ss",
          "yyyy-MM-dd HH:mm:ss.SSS",
          // 2.b) with ISO-8601 time zone
          "yyyy-MM-dd HH:mmX",
          "yyyy-MM-dd HH:mmXX",
          "yyyy-MM-dd HH:mmXXX",
          "yyyy-MM-dd HH:mm:ssX",
          "yyyy-MM-dd HH:mm:ssXX",
          "yyyy-MM-dd HH:mm:ssXXX",
          "yyyy-MM-dd HH:mm:ss.SSSX",
          "yyyy-MM-dd HH:mm:ss.SSSXX",
          "yyyy-MM-dd HH:mm:ss.SSSXXX",
          // 2.c) with generic time zone
          "yyyy-MM-dd HH:mm z",
          "yyyy-MM-dd HH:mm:ss z",
          "yyyy-MM-dd HH:mm:ss.SSS z",
          // 3) date patterns without time
          // 3.a) without time zone
          "yyyy-MM-dd",
          // 3.b) with ISO-8601 time zone
          "yyyy-MM-ddX",
          "yyyy-MM-ddXX",
          "yyyy-MM-ddXXX",
          // 3.c) with generic time zone
          "yyyy-MM-dd z"
        };
  
    private final FastThreadLocal<SimpleDateFormat> parser;
  
    private final FastThreadLocal<SimpleDateFormat> formatter;
  
    /**
     * Creates a new {@code TimestampCodec} that uses the system's {@linkplain ZoneId#systemDefault()
     * default time zone} to parse timestamp literals that do not include any time zone information.
     */
    public TimestampCodec() {
      this(ZoneId.systemDefault());
    }
  
    /**
     * Creates a new {@code TimestampCodec} that uses the given {@link ZoneId} to parse timestamp
     * literals that do not include any time zone information.
     */
    public TimestampCodec(ZoneId defaultZoneId) {
      parser =
          new FastThreadLocal<SimpleDateFormat>() {
            @Override
            protected SimpleDateFormat initialValue() {
              SimpleDateFormat parser = new SimpleDateFormat();
              parser.setLenient(false);
              parser.setTimeZone(TimeZone.getTimeZone(defaultZoneId));
              return parser;
            }
          };
      formatter =
          new FastThreadLocal<SimpleDateFormat>() {
            @Override
            protected SimpleDateFormat initialValue() {
              SimpleDateFormat parser = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSXXX");
              parser.setTimeZone(TimeZone.getTimeZone(defaultZoneId));
              return parser;
            }
          };
    }
  
    @NonNull
    @Override
    public GenericType<Instant> getJavaType() {
      return GenericType.INSTANT;
    }
  
    @NonNull
    @Override
    public DataType getCqlType() {
      return DataTypes.TIMESTAMP;
    }
  
    @Override
    public boolean accepts(@NonNull Object value) {
      return value instanceof Instant;
    }
  
    @Override
    public boolean accepts(@NonNull Class<?> javaClass) {
      return javaClass == Instant.class;
    }
  
    @Nullable
    @Override
    public ByteBuffer encode(@Nullable Instant value, @NonNull ProtocolVersion protocolVersion) {
      return (value == null)
          ? null
          : TypeCodecs.BIGINT.encodePrimitive(value.toEpochMilli(), protocolVersion);
    }
  
    @Nullable
    @Override
    public Instant decode(@Nullable ByteBuffer bytes, @NonNull ProtocolVersion protocolVersion) {
      return (bytes == null || bytes.remaining() == 0)
          ? null
          : Instant.ofEpochMilli(TypeCodecs.BIGINT.decodePrimitive(bytes, protocolVersion));
    }
  
    @NonNull
    @Override
    public String format(@Nullable Instant value) {
      return (value == null) ? "NULL" : Strings.quote(formatter.get().format(Date.from(value)));
    }
  
    @Nullable
    @Override
    public Instant parse(@Nullable String value) {
      if (value == null || value.isEmpty() || value.equalsIgnoreCase("NULL")) {
        return null;
      }
      String unquoted = Strings.unquote(value);
      if (Strings.isLongLiteral(unquoted)) {
        // Numeric literals may be quoted or not
        try {
          return Instant.ofEpochMilli(Long.parseLong(unquoted));
        } catch (NumberFormatException e) {
          throw new IllegalArgumentException(
              String.format("Cannot parse timestamp value from \"%s\"", value));
        }
      } else {
        // Alphanumeric literals must be quoted
        if (!Strings.isQuoted(value)) {
          throw new IllegalArgumentException(
              String.format("Alphanumeric timestamp literal must be quoted: \"%s\"", value));
        }
        SimpleDateFormat parser = this.parser.get();
        TimeZone timeZone = parser.getTimeZone();
        ParsePosition pos = new ParsePosition(0);
        for (String pattern : DATE_STRING_PATTERNS) {
          parser.applyPattern(pattern);
          pos.setIndex(0);
          try {
            Date date = parser.parse(unquoted, pos);
            if (date != null && pos.getIndex() == unquoted.length()) {
              return date.toInstant();
            }
          } finally {
            // restore the parser's default time zone, it might have been modified by the call to
            // parse()
            parser.setTimeZone(timeZone);
          }
        }
        throw new IllegalArgumentException(
            String.format("Cannot parse timestamp value from \"%s\"", value));
      }
    }
  
    @NonNull
    @Override
    public Optional<Integer> serializedSize() {
      return Optional.of(8);
    }
  }
  