michael@0: /**
michael@0:  * Copyright (c) 2012, Ben Fortuna
michael@0:  * All rights reserved.
michael@0:  *
michael@0:  * Redistribution and use in source and binary forms, with or without
michael@0:  * modification, are permitted provided that the following conditions
michael@0:  * are met:
michael@0:  *
michael@0:  *  o Redistributions of source code must retain the above copyright
michael@0:  * notice, this list of conditions and the following disclaimer.
michael@0:  *
michael@0:  *  o Redistributions in binary form must reproduce the above copyright
michael@0:  * notice, this list of conditions and the following disclaimer in the
michael@0:  * documentation and/or other materials provided with the distribution.
michael@0:  *
michael@0:  *  o Neither the name of Ben Fortuna nor the names of any other contributors
michael@0:  * may be used to endorse or promote products derived from this software
michael@0:  * without specific prior written permission.
michael@0:  *
michael@0:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0:  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0:  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
michael@0:  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
michael@0:  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
michael@0:  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
michael@0:  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
michael@0:  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
michael@0:  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
michael@0:  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
michael@0:  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0:  */
michael@0: package net.fortuna.ical4j.model;
michael@0: 
michael@0: import java.util.Calendar;
michael@0: import java.util.Collections;
michael@0: import java.util.Date;
michael@0: import java.util.List;
michael@0: 
michael@0: import net.fortuna.ical4j.model.component.Daylight;
michael@0: import net.fortuna.ical4j.model.component.Observance;
michael@0: import net.fortuna.ical4j.model.component.VTimeZone;
michael@0: import net.fortuna.ical4j.model.property.TzId;
michael@0: import net.fortuna.ical4j.model.property.TzOffsetTo;
michael@0: 
michael@0: /**
michael@0:  * $Id$
michael@0:  *
michael@0:  * Created on 13/09/2005
michael@0:  *
michael@0:  * A Java timezone implementation based on an underlying VTimeZone
michael@0:  * definition.
michael@0:  * @author Ben Fortuna
michael@0:  */
michael@0: public class TimeZone extends java.util.TimeZone {
michael@0:     
michael@0:     private static final long serialVersionUID = -5620979316746547234L;
michael@0:     
michael@0:     private final VTimeZone vTimeZone;
michael@0:     private final int rawOffset;
michael@0:     
michael@0:     /**
michael@0:      * Constructs a new instance based on the specified VTimeZone.
michael@0:      * @param vTimeZone a VTIMEZONE object instance
michael@0:      */
michael@0:     public TimeZone(final VTimeZone vTimeZone) {
michael@0:         this.vTimeZone = vTimeZone;
michael@0:         final TzId tzId = (TzId) vTimeZone.getProperty(Property.TZID);
michael@0:         setID(tzId.getValue());
michael@0:         this.rawOffset = getRawOffset(vTimeZone);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * {@inheritDoc}
michael@0:      */
michael@3:     public final int getOffset(final int era, final int year, final int month, final int dayOfMonth,
michael@0:             final int dayOfWeek, final int milliseconds) {
michael@3: 
michael@3:         // calculate time of day
michael@3:         int ms = milliseconds;
michael@3:         final int hour = ms / 3600000;
michael@3:         ms -= hour*3600000;
michael@3:         final int minute = ms / 60000;
michael@3:         ms -= minute*60000;
michael@3:         final int second = ms / 1000;
michael@3:         ms -= second*1000;
michael@3: 
michael@3:         final Calendar cal = Calendar.getInstance();
michael@3:         cal.clear();	// don't retain current date/time, it may disturb the calculation		
michael@0:         
michael@3:     	// set date and time
michael@0:         cal.set(Calendar.ERA, era);
michael@0:         cal.set(Calendar.DAY_OF_WEEK, dayOfWeek);
michael@3:         cal.set(year, month, dayOfMonth, hour, minute, second);
michael@3:         cal.set(Calendar.MILLISECOND, ms);
michael@3:         
michael@0:         final Observance observance = vTimeZone.getApplicableObservance(new DateTime(cal.getTime()));
michael@0:         if (observance != null) {
michael@0:             final TzOffsetTo offset = (TzOffsetTo) observance.getProperty(Property.TZOFFSETTO);
michael@0:             return (int) offset.getOffset().getOffset();
michael@0:         }
michael@0:         return 0;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * {@inheritDoc}
michael@0:      */
michael@0:     public int getOffset(long date) {
michael@0:         final Observance observance = vTimeZone.getApplicableObservance(new DateTime(date));
michael@0:         if (observance != null) {
michael@0:             final TzOffsetTo offset = (TzOffsetTo) observance.getProperty(Property.TZOFFSETTO);
michael@3:             if (offset.getOffset().getOffset() < getRawOffset()) {
michael@3:             	return getRawOffset();
michael@3:             }
michael@3:             else {
michael@3:             	return (int) offset.getOffset().getOffset();
michael@3:             }
michael@0:         }
michael@0:         return 0;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * {@inheritDoc}
michael@0:      */
michael@0:     public final int getRawOffset() {
michael@0:         return rawOffset;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Determines if the specified date is in daylight time according to
michael@0:      * this timezone. This is done by finding the latest supporting
michael@0:      * observance for the specified date and identifying whether it is
michael@0:      * daylight time.
michael@0:      * @param date a date instance
michael@0:      * @return true if the specified date is in daylight time, otherwise false
michael@0:      */
michael@0:     public final boolean inDaylightTime(final Date date) {
michael@0:         final Observance observance = vTimeZone.getApplicableObservance(new DateTime(date));
michael@0:         return (observance != null && observance instanceof Daylight);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * {@inheritDoc}
michael@0:      */
michael@0:     public final void setRawOffset(final int offsetMillis) {
michael@0:         throw new UnsupportedOperationException("Updates to the VTIMEZONE object must be performed directly");
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * {@inheritDoc}
michael@0:      */
michael@0:     public final boolean useDaylightTime() {
michael@0:         final ComponentList daylights = vTimeZone.getObservances().getComponents(Observance.DAYLIGHT);
michael@0:         return (!daylights.isEmpty());
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * @return Returns the VTimeZone backing this instance.
michael@0:      */
michael@0:     public final VTimeZone getVTimeZone() {
michael@0:         return vTimeZone;
michael@0:     }
michael@0: 
michael@0:     private static final int getRawOffset(VTimeZone vt) {
michael@0:         
michael@0:         List seasonalTimes = vt.getObservances().getComponents(Observance.STANDARD);
michael@0:         // if no standard time use daylight time..
michael@3:         if (seasonalTimes.isEmpty()) {
michael@0:             seasonalTimes = vt.getObservances().getComponents(Observance.DAYLIGHT);
michael@3:             if (seasonalTimes.isEmpty()) {
michael@3:                 return 0;
michael@3:             }
michael@0:         }
michael@0:         Observance latestSeasonalTime = null;
michael@3:         if (seasonalTimes.size() > 1) {
michael@3:             // per java spec and when dealing with historical time,
michael@3:             // rawoffset is the raw offset at the current date
michael@3:             final DateTime now = new DateTime();
michael@3:             Date latestOnset = null;
michael@3:             for (int i = 0; i < seasonalTimes.size(); i++) {
michael@3:                 Observance seasonalTime = (Observance) seasonalTimes.get(i);
michael@3:                 Date onset = seasonalTime.getLatestOnset(now);
michael@3:                 if (onset == null) {
michael@3:                     continue;
michael@3:                 }
michael@3:                 if (latestOnset == null || onset.after(latestOnset)) {
michael@3:                     latestOnset = onset;
michael@3:                     latestSeasonalTime = seasonalTime;
michael@3:                 }
michael@0:             }
michael@3:         } else {
michael@3:             latestSeasonalTime = (Observance)seasonalTimes.get(0);
michael@0:         }
michael@0:         if (latestSeasonalTime != null) {
michael@0:             final TzOffsetTo offsetTo = (TzOffsetTo) latestSeasonalTime.getProperty(Property.TZOFFSETTO);
michael@0:             if (offsetTo != null) {
michael@0:                 return (int) offsetTo.getOffset().getOffset();
michael@0:             }
michael@0:         }
michael@0:         return 0;
michael@0:     }
michael@3: 
michael@3:     public boolean equals(Object o) {
michael@3:         if (this == o) return true;
michael@3:         if (o == null || getClass() != o.getClass()) return false;
michael@3: 
michael@3:         TimeZone timeZone = (TimeZone) o;
michael@3: 
michael@3:         if (rawOffset != timeZone.rawOffset) return false;
michael@3:         if (vTimeZone != null ? !vTimeZone.equals(timeZone.vTimeZone) : timeZone.vTimeZone != null) return false;
michael@3: 
michael@3:         return true;
michael@3:     }
michael@3: 
michael@3:     public int hashCode() {
michael@3:         int result = vTimeZone != null ? vTimeZone.hashCode() : 0;
michael@3:         result = 31 * result + rawOffset;
michael@3:         return result;
michael@3:     }
michael@0: }