/*
    *  Copyright 2010, 2011 Chris Pheby
    *
    *  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.
   */
  package org.jadira.bindings.core.jdk;
  
  import java.text.ParseException;
  import java.text.SimpleDateFormat;
  import java.util.Calendar;
  import java.util.GregorianCalendar;
  import java.util.TimeZone;
  
  import org.jadira.bindings.core.api.Binding;
  import org.jadira.bindings.core.api.BindingException;
  
  /**
   * Binds a Calendar to a String
   */
  public class CalendarStringBinding extends AbstractStringBinding<Calendar> implements Binding<Calendar, String> {
  
      private static final ThreadLocal<SimpleDateFormat> DATE_FORMAT = new ThreadLocal<SimpleDateFormat>() {
          @Override
          public SimpleDateFormat initialValue() {
              return new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZ");
          }
      };
  
      /**
       * {@inheritDoc}
       */
      @Override
      public Calendar unmarshal(String object) {
  
          if (object.length() < 31 || object.charAt(26) != ':' || object.charAt(29) != '['
                  || object.charAt(object.length() - 1) != ']') {
              throw new IllegalArgumentException("Unable to parse calendar: " + object);
          }
          TimeZone zone = TimeZone.getTimeZone(object.substring(30, object.length() - 1));
  
          String parseableDateString = object.substring(0, 26) + object.substring(27, 29);
  
          GregorianCalendar cal = new GregorianCalendar(zone);
          cal.setTimeInMillis(0);
          DATE_FORMAT.get().setCalendar(cal);
  
          try {
              DATE_FORMAT.get().parseObject(parseableDateString);
              return DATE_FORMAT.get().getCalendar();
          } catch (ParseException ex) {
              throw new BindingException(ex.getMessage(), ex);
          }
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public String marshal(Calendar object) {
  
          if (object instanceof GregorianCalendar) {
  
              GregorianCalendar cal = (GregorianCalendar) object;
  
              DATE_FORMAT.get().setCalendar(cal);
              String str = DATE_FORMAT.get().format(cal.getTime());
  
              String printableDateString = str.substring(0, 26) + ":" + str.substring(26) + "["
                      + cal.getTimeZone().getID() + "]";
              return printableDateString;
          } else {
              throw new IllegalArgumentException("CalendarStringBinding can only support "
                      + GregorianCalendar.class.getSimpleName());
          }
      }
  
      /**
       * {@inheritDoc}
       */
      /* @Override */
  	public Class<Calendar> getBoundClass() {
  		return Calendar.class;
  	}
  }