/*
 * 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 org.eigenbase.util14;

import java.sql.*;

import java.text.*;

/**
 * ZonelessTimestamp is a timestamp value without a time zone.
 */
public class ZonelessTimestamp extends ZonelessDatetime {
  //~ Static fields/initializers ---------------------------------------------

  /**
   * SerialVersionUID created with JDK 1.5 serialver tool.
   */
  private static final long serialVersionUID = -6829714640541648394L;

  //~ Instance fields --------------------------------------------------------

  protected final int precision;

  protected transient Timestamp tempTimestamp;

  //~ Constructors -----------------------------------------------------------

  /**
   * Constructs a ZonelessTimestamp.
   */
  public ZonelessTimestamp() {
    this.precision = 0;
  }

  /**
   * Constructs a ZonelessTimestamp with precision.
   *
   * <p>The precision is the number of digits to the right of the decimal
   * point in the seconds value. For example, a <code>TIMESTAMP(3)</code> has
   * a precision to milliseconds.
   *
   * @param precision Number of digits of precision
   */
  public ZonelessTimestamp(int precision) {
    this.precision = precision;
  }

  //~ Methods ----------------------------------------------------------------

  // implement ZonelessDatetime
  public Object toJdbcObject() {
    return new Timestamp(getJdbcTimestamp(DateTimeUtil.DEFAULT_ZONE));
  }

  /**
   * Converts this ZonelessTimestamp to a java.sql.Timestamp and formats it
   * via the {@link java.sql.Timestamp#toString() toString()} method of that
   * class.
   *
   * <p>Note: Jdbc formatting always includes a decimal point and at least one
   * digit of milliseconds precision. Trailing zeros, except for the first one
   * after the decimal point, do not appear in the output.
   *
   * @return the formatted time string
   */
  public String toString() {
    Timestamp ts =
        getTempTimestamp(getJdbcTimestamp(DateTimeUtil.DEFAULT_ZONE));

    // Remove trailing '.0' so that format is consistent with SQL spec for
    // CAST(TIMESTAMP(0) TO VARCHAR). E.g. "1969-12-31 16:00:00.0"
    // becomes "1969-12-31 16:00:00"
    return ts.toString().substring(0, 19);
  }

  /**
   * Formats this ZonelessTimestamp via a SimpleDateFormat. This method does
   * not display milliseconds precision.
   *
   * @param format format string, as required by SimpleDateFormat
   * @return the formatted timestamp string
   */
  public String toString(String format) {
    DateFormat formatter = getFormatter(format);
    Timestamp ts = getTempTimestamp(getTime());
    return formatter.format(ts);
  }

  /**
   * Parses a string as a ZonelessTimestamp.
   *
   * <p>This method's parsing is strict and may parse fractional seconds (as
   * opposed to just milliseconds.)
   *
   * @param s a string representing a time in ISO format, i.e. according to
   *          the SimpleDateFormat string "yyyy-MM-dd HH:mm:ss"
   * @return the parsed time, or null if parsing failed
   */
  public static ZonelessTimestamp parse(String s) {
    return parse(s, DateTimeUtil.TIMESTAMP_FORMAT_STRING);
  }

  /**
   * Parses a string as a ZonelessTimestamp using a given format string.
   *
   * <p>This method's parsing is strict and may parse fractional seconds (as
   * opposed to just milliseconds.)
   *
   * @param s      a string representing a time in ISO format, i.e. according to
   *               the SimpleDateFormat string "yyyy-MM-dd HH:mm:ss"
   * @param format format string as per {@link SimpleDateFormat}
   * @return the parsed timestamp, or null if parsing failed
   */
  public static ZonelessTimestamp parse(String s, String format) {
    DateTimeUtil.PrecisionTime pt =
        DateTimeUtil.parsePrecisionDateTimeLiteral(
            s,
            format,
            DateTimeUtil.GMT_ZONE);
    if (pt == null) {
      return null;
    }
    ZonelessTimestamp zt = new ZonelessTimestamp(pt.getPrecision());
    zt.setZonelessTime(pt.getCalendar().getTime().getTime());
    return zt;
  }

  /**
   * Gets a temporary Timestamp object. The same object is returned every
   * time.
   */
  protected Timestamp getTempTimestamp(long value) {
    if (tempTimestamp == null) {
      tempTimestamp = new Timestamp(value);
    } else {
      tempTimestamp.setTime(value);
    }
    return tempTimestamp;
  }
}

// End ZonelessTimestamp.java