/*
    *  Copyright 2001-2005 Stephen Colebourne
    *
    *  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.joda.time.chrono;
  
  import org.joda.time.DateTimeFieldType;
  import org.joda.time.DurationField;
  import org.joda.time.field.FieldUtils;
  import org.joda.time.field.ImpreciseDateTimeField;
  
  /**
   * A year field suitable for many calendars.
   *
   * @author Guy Allard
   * @author Stephen Colebourne
   * @author Brian S O'Neill
   * @since 1.1, refactored from GJYearDateTimeField
   */
  class BasicYearDateTimeField extends ImpreciseDateTimeField {
  
      /** Serialization version. */
      private static final long serialVersionUID = -98628754872287L;
  
      /** The underlying basic chronology. */
      protected final BasicChronology iChronology;
  
      /**
       * Restricted constructor.
       * 
       * @param chronology  the chronology this field belogs to
       */
      BasicYearDateTimeField(BasicChronology chronology) {
          super(DateTimeFieldType.year(), chronology.getAverageMillisPerYear());
          iChronology = chronology;
      }
  
      public boolean isLenient() {
          return false;
      }
  
      public int get(long instant) {
          return iChronology.getYear(instant);
      }
  
      public long add(long instant, int years) {
          if (years == 0) {
              return instant;
          }
          int thisYear = get(instant);
          int newYear = FieldUtils.safeAdd(thisYear, years);
          return set(instant, newYear);
      }
  
      public long add(long instant, long years) {
          return add(instant, FieldUtils.safeToInt(years));
      }
  
      public long addWrapField(long instant, int years) {
          if (years == 0) {
              return instant;
          }
          // Return newly calculated millis value
          int thisYear = iChronology.getYear(instant);
          int wrappedYear = FieldUtils.getWrappedValue
              (thisYear, years, iChronology.getMinYear(), iChronology.getMaxYear());
          return set(instant, wrappedYear);
      }
  
      public long set(long instant, int year) {
          FieldUtils.verifyValueBounds
              (this, year, iChronology.getMinYear(), iChronology.getMaxYear());
          return iChronology.setYear(instant, year);
      }
  
      public long getDifferenceAsLong(long minuendInstant, long subtrahendInstant) {
          if (minuendInstant < subtrahendInstant) {
              return -iChronology.getYearDifference(subtrahendInstant, minuendInstant);
          }
          return iChronology.getYearDifference(minuendInstant, subtrahendInstant);
      }
  
      public DurationField getRangeDurationField() {
          return null;
      }
  
      public boolean isLeap(long instant) {
          return iChronology.isLeapYear(get(instant));
     }
 
     public int getLeapAmount(long instant) {
         if (iChronology.isLeapYear(get(instant))) {
             return 1;
         } else {
             return 0;
         }
     }
 
     public DurationField getLeapDurationField() {
         return iChronology.days();
     }
 
     public int getMinimumValue() {
         return iChronology.getMinYear();
     }
 
     public int getMaximumValue() {
         return iChronology.getMaxYear();
     }
 
     public long roundFloor(long instant) {
         return iChronology.getYearMillis(get(instant));
     }
 
     public long roundCeiling(long instant) {
         int year = get(instant);
         long yearStartMillis = iChronology.getYearMillis(year);
         if (instant != yearStartMillis) {
             // Bump up to start of next year.
             instant = iChronology.getYearMillis(year + 1);
         }
         return instant;
     }
 
     public long remainder(long instant) {
         return instant - roundFloor(instant);
     }
 
     /**
      * Serialization singleton
      */
     private Object readResolve() {
         return iChronology.year();
     }
 }