/*
    * Copyright 2003 - 2013 The eFaps Team
    *
    * Licensed 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.
   *
   * Revision:        $Rev$
   * Last Changed:    $Date$
   * Last Changed By: $Author$
   */
  
  package org.efaps.admin.datamodel.attributetype;
  
  import java.sql.SQLException;
  import java.sql.Timestamp;
  import java.util.ArrayList;
  import java.util.Date;
  import java.util.List;
  
  import org.efaps.admin.EFapsSystemConfiguration;
  import org.efaps.admin.KernelSettings;
  import org.efaps.admin.datamodel.Attribute;
  import org.efaps.db.Context;
  import org.efaps.db.wrapper.AbstractSQLInsertUpdate;
  import org.efaps.util.DateTimeUtil;
  import org.efaps.util.EFapsException;
  import org.joda.time.DateTime;
  import org.joda.time.DateTimeZone;
  import org.joda.time.ReadableDateTime;
  import org.joda.time.chrono.ISOChronology;
  
  /**
   * @author The eFaps Team
   * @version $Id$
   */
  public class DateTimeType
      extends AbstractType
  {
      /**
       * Needed for serialization.
       */
      private static final long serialVersionUID = 1L;
  
      /**
       * {@inheritDoc}
       * @throws EFapsException
       */
      @Override
      public Object readValue(final Attribute _attribute,
                              final List<Object> _objectList)
          throws EFapsException
      {
          // reads the Value from "Admin_Common_DataBaseTimeZone"
          final String timezoneID = EFapsSystemConfiguration.get().getAttributeValue(KernelSettings.DBTIMEZONE);
          final ISOChronology chron;
          if (timezoneID != null) {
              final DateTimeZone timezone = DateTimeZone.forID(timezoneID);
              chron = ISOChronology.getInstance(timezone);
          } else {
              chron = ISOChronology.getInstanceUTC();
          }
  
          final List<DateTime> ret = new ArrayList<DateTime>();
          for (final Object object : _objectList) {
              if (object instanceof Timestamp || object instanceof Date) {
                  // to avoid the automatic "correction" of the timezone first a local date must be made
                  // and than a new Date with the correct timezone must be created
                  final DateTime dateTime = new DateTime(object);
                  final DateTime unlocalized = new DateTime(dateTime.getYear(),
                                  dateTime.getMonthOfYear(),
                                  dateTime.getDayOfMonth(),
                                  dateTime.getHourOfDay(),
                                  dateTime.getMinuteOfHour(),
                                  dateTime.getSecondOfMinute(),
                                  dateTime.getMillisOfSecond(),
                                  chron);
                  ret.add(unlocalized);
              } else if (object != null) {
                  ret.add(new DateTime());
              } else {
                  ret.add(null);
              }
          }
          return _objectList.size() > 0 ? (ret.size() > 1 ? ret : ret.get(0)) : null;
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
     protected void prepare(final AbstractSQLInsertUpdate<?> _insertUpdate,
                            final Attribute _attribute,
                            final Object... _values)
         throws SQLException
     {
         checkSQLColumnSize(_attribute, 1);
         try {
             _insertUpdate.column(_attribute.getSqlColNames().get(0), eval(_values));
         } catch (final EFapsException e) {
             throw new SQLException(e);
         }
     }
 
 
     /**
      * The value that can be set is a Date, a DateTime or a String
      * yyyy-MM-dd'T'HH:mm:ss.SSSZZ. It will be normalized to ISO Calender with
      * TimeZone from SystemAttribute Admin_Common_DataBaseTimeZone. In case that
      * the SystemAttribute is missing UTC will be used.
      *
      * @param _value value to evaluate
      * @return evaluated value
      * @throws EFapsException on error
      */
     protected Timestamp eval(final Object[] _value)
         throws EFapsException
     {
         final Timestamp ret;
         if ((_value == null) || (_value.length == 0) || (_value[0] == null)) {
             ret = null;
         } else  {
             final DateTime dateTime = DateTimeUtil.translateFromUI(_value[0]);
             // until now we have a time that depends on the timezone of the application server
             // to convert it in a timestamp for the efaps database the timezone information (mainly the offset)
             // must be removed. This is done by creating a local date with the same, date and time.
             // this guarantees that the datetime inserted into the database depends on the setting
             // in the configuration and not on the timezone for the application server.
             final DateTime localized = new DateTime(dateTime.getYear(),
                                                     dateTime.getMonthOfYear(),
                                                     dateTime.getDayOfMonth(),
                                                     dateTime.getHourOfDay(),
                                                     dateTime.getMinuteOfHour(),
                                                     dateTime.getSecondOfMinute(),
                                                     dateTime.getMillisOfSecond());
             ret = (localized != null) ? new Timestamp(localized.getMillis()) : null;
         }
         return ret;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String toString4Where(final Object _value)
         throws EFapsException
     {
         String ret = "";
         if (_value instanceof ReadableDateTime) {
             ret = Context.getDbType().getStr4DateTime((ReadableDateTime) _value);
         } else if (_value instanceof String) {
             ret = (String) _value;
         }
         return ret;
     }
 }