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.io.IOException;
michael@0: import java.io.Serializable;
michael@0: import java.util.Calendar;
michael@0: import java.util.Date;
michael@0: import java.util.StringTokenizer;
michael@0: import net.fortuna.ical4j.util.Dates;
michael@0: 
michael@4: import org.apache.commons.lang3.builder.HashCodeBuilder;
michael@0: 
michael@0: /**
michael@0:  * $Id$
michael@0:  *
michael@0:  * Created on 20/06/2005
michael@0:  *
michael@0:  * Represents a duration of time in iCalendar. Note that according to RFC2445 durations represented in weeks are
michael@0:  * mutually exclusive of other duration fields.
michael@0:  * 
michael@0:  * <pre>
michael@0:  *  4.3.6   Duration
michael@0:  *  
michael@0:  *     Value Name: DURATION
michael@0:  *  
michael@0:  *     Purpose: This value type is used to identify properties that contain
michael@0:  *     a duration of time.
michael@0:  *  
michael@0:  *     Formal Definition: The value type is defined by the following
michael@0:  *     notation:
michael@0:  *  
michael@0:  *       dur-value  = ([&quot;+&quot;] / &quot;-&quot;) &quot;P&quot; (dur-date / dur-time / dur-week)
michael@0:  *  
michael@0:  *       dur-date   = dur-day [dur-time]
michael@0:  *       dur-time   = &quot;T&quot; (dur-hour / dur-minute / dur-second)
michael@0:  *       dur-week   = 1*DIGIT &quot;W&quot;
michael@0:  *       dur-hour   = 1*DIGIT &quot;H&quot; [dur-minute]
michael@0:  *       dur-minute = 1*DIGIT &quot;M&quot; [dur-second]
michael@0:  *       dur-second = 1*DIGIT &quot;S&quot;
michael@0:  *       dur-day    = 1*DIGIT &quot;D&quot;
michael@0:  * </pre>
michael@0:  * 
michael@0:  * @author Ben Fortuna
michael@0:  */
michael@0: public class Dur implements Comparable, Serializable {
michael@0: 
michael@0:     private static final long serialVersionUID = 5013232281547134583L;
michael@0: 
michael@0:     private static final int DAYS_PER_WEEK = 7;
michael@0: 
michael@0:     private static final int SECONDS_PER_MINUTE = 60;
michael@0: 
michael@0:     private static final int MINUTES_PER_HOUR = 60;
michael@0: 
michael@0:     private static final int HOURS_PER_DAY = 24;
michael@0: 
michael@0:     private static final int DAYS_PER_YEAR = 365;
michael@0: 
michael@0:     private boolean negative;
michael@0: 
michael@0:     private int weeks;
michael@0: 
michael@0:     private int days;
michael@0: 
michael@0:     private int hours;
michael@0: 
michael@0:     private int minutes;
michael@0: 
michael@0:     private int seconds;
michael@0: 
michael@0:     /**
michael@0:      * Constructs a new duration instance from a string representation.
michael@0:      * @param value a string representation of a duration
michael@0:      */
michael@0:     public Dur(final String value) {
michael@0:         negative = false;
michael@0:         weeks = 0;
michael@0:         days = 0;
michael@0:         hours = 0;
michael@0:         minutes = 0;
michael@0:         seconds = 0;
michael@0: 
michael@0:         String token = null;
michael@0:         String prevToken = null;
michael@0: 
michael@0:         final StringTokenizer t = new StringTokenizer(value, "+-PWDTHMS", true);
michael@0:         while (t.hasMoreTokens()) {
michael@0:             prevToken = token;
michael@0:             token = t.nextToken();
michael@0: 
michael@0:             if ("+".equals(token)) {
michael@0:                 negative = false;
michael@0:             }
michael@0:             else if ("-".equals(token)) {
michael@0:                 negative = true;
michael@0:             }
michael@0:             else if ("P".equals(token)) {
michael@0:                 // does nothing..
michael@0:             }
michael@0:             else if ("W".equals(token)) {
michael@0:                 weeks = Integer.parseInt(prevToken);
michael@0:             }
michael@0:             else if ("D".equals(token)) {
michael@0:                 days = Integer.parseInt(prevToken);
michael@0:             }
michael@0:             else if ("T".equals(token)) {
michael@0:                 // does nothing..
michael@0:             }
michael@0:             else if ("H".equals(token)) {
michael@0:                 hours = Integer.parseInt(prevToken);
michael@0:             }
michael@0:             else if ("M".equals(token)) {
michael@0:                 minutes = Integer.parseInt(prevToken);
michael@0:             }
michael@0:             else if ("S".equals(token)) {
michael@0:                 seconds = Integer.parseInt(prevToken);
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Constructs a new duration from the specified weeks.
michael@0:      * @param weeks a duration in weeks.
michael@0:      */
michael@0:     public Dur(final int weeks) {
michael@0:         this.weeks = Math.abs(weeks);
michael@0:         this.days = 0;
michael@0:         this.hours = 0;
michael@0:         this.minutes = 0;
michael@0:         this.seconds = 0;
michael@0:         this.negative = weeks < 0;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Constructs a new duration from the specified arguments.
michael@0:      * @param days duration in days
michael@0:      * @param hours duration in hours
michael@0:      * @param minutes duration in minutes
michael@0:      * @param seconds duration in seconds
michael@0:      */
michael@0:     public Dur(final int days, final int hours, final int minutes,
michael@0:             final int seconds) {
michael@0: 
michael@0:         if (!(days >= 0 && hours >= 0 && minutes >= 0 && seconds >= 0)
michael@0:                 && !(days <= 0 && hours <= 0 && minutes <= 0 && seconds <= 0)) {
michael@0:             
michael@0:             throw new IllegalArgumentException("Invalid duration representation");
michael@0:         }
michael@0:         
michael@0:         this.weeks = 0;
michael@0:         this.days = Math.abs(days);
michael@0:         this.hours = Math.abs(hours);
michael@0:         this.minutes = Math.abs(minutes);
michael@0:         this.seconds = Math.abs(seconds);
michael@0:         
michael@0:         this.negative = days < 0 || hours < 0 || minutes < 0 || seconds < 0;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Constructs a new duration representing the time between the two specified dates. The end date may precede the
michael@0:      * start date in order to represent a negative duration.
michael@0:      * @param date1 the first date of the duration
michael@0:      * @param date2 the second date of the duration
michael@0:      */
michael@0:     public Dur(final Date date1, final Date date2) {
michael@0:         
michael@0:         Date start = null;
michael@0:         Date end = null;
michael@0:         
michael@0:         // Negative range? (start occurs after end)
michael@0:         negative = date1.compareTo(date2) > 0;
michael@0:         if (negative) {
michael@0:             // Swap the dates (which eliminates the need to bother with
michael@0:             // negative after this!)
michael@0:             start = date2;
michael@0:             end = date1;
michael@0:         }
michael@0:         else {
michael@0:             start = date1;
michael@0:             end = date2;
michael@0:         }
michael@0: 
michael@0:         final Calendar startCal;
michael@0:         if (start instanceof net.fortuna.ical4j.model.Date) {
michael@0:             startCal = Dates.getCalendarInstance((net.fortuna.ical4j.model.Date)start);
michael@0:         } else {
michael@0:             startCal = Calendar.getInstance();
michael@0:         }
michael@0:         startCal.setTime(start);
michael@0:         final Calendar endCal = Calendar.getInstance(startCal.getTimeZone());
michael@0:         endCal.setTime(end);
michael@0: 
michael@0:         // Init our duration interval (which is in units that evolve as we
michael@0:         // compute, below)
michael@0:         int dur = 0;
michael@0: 
michael@0:         // Count days to get to the right year (loop in the very rare chance
michael@0:         // that a leap year causes us to come up short)
michael@0:         int nYears = endCal.get(Calendar.YEAR) - startCal.get(Calendar.YEAR);
michael@0:         while (nYears > 0) {
michael@0:             startCal.add(Calendar.DATE, DAYS_PER_YEAR * nYears);
michael@0:             dur += DAYS_PER_YEAR * nYears;
michael@0:             nYears = endCal.get(Calendar.YEAR) - startCal.get(Calendar.YEAR);
michael@0:         }
michael@0: 
michael@0:         // Count days to get to the right day
michael@0:         dur += endCal.get(Calendar.DAY_OF_YEAR)
michael@0:                 - startCal.get(Calendar.DAY_OF_YEAR);
michael@0: 
michael@0:         // Count hours to get to right hour
michael@0:         dur *= HOURS_PER_DAY; // days -> hours
michael@0:         dur += endCal.get(Calendar.HOUR_OF_DAY)
michael@0:                 - startCal.get(Calendar.HOUR_OF_DAY);
michael@0: 
michael@0:         // ... to the right minute
michael@0:         dur *= MINUTES_PER_HOUR; // hours -> minutes
michael@0:         dur += endCal.get(Calendar.MINUTE) - startCal.get(Calendar.MINUTE);
michael@0: 
michael@0:         // ... and second
michael@0:         dur *= SECONDS_PER_MINUTE; // minutes -> seconds
michael@0:         dur += endCal.get(Calendar.SECOND) - startCal.get(Calendar.SECOND);
michael@0: 
michael@0:         // Now unwind our units
michael@0:         seconds = dur % SECONDS_PER_MINUTE;
michael@0:         dur = dur / SECONDS_PER_MINUTE; // seconds -> minutes (drop remainder seconds)
michael@0:         minutes = dur % MINUTES_PER_HOUR;
michael@0:         dur /= MINUTES_PER_HOUR; // minutes -> hours (drop remainder minutes)
michael@0:         hours = dur % HOURS_PER_DAY;
michael@0:         dur /= HOURS_PER_DAY; // hours -> days (drop remainder hours)
michael@0:         days = dur;
michael@0:         weeks = 0;
michael@0: 
michael@0:         // Special case for week-only representation
michael@0:         if (seconds == 0 && minutes == 0 && hours == 0
michael@0:                 && (days % DAYS_PER_WEEK) == 0) {
michael@0:             weeks = days / DAYS_PER_WEEK;
michael@0:             days = 0;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Returns a date representing the end of this duration from the specified start date.
michael@0:      * @param start the date to start the duration
michael@0:      * @return the end of the duration as a date
michael@0:      */
michael@0:     public final Date getTime(final Date start) {
michael@0:         final Calendar cal;
michael@0:         if (start instanceof net.fortuna.ical4j.model.Date) {
michael@0:             cal = Dates.getCalendarInstance((net.fortuna.ical4j.model.Date)start);
michael@0:         } else {
michael@0:             cal = Calendar.getInstance();
michael@0:         }
michael@0: 
michael@0:         cal.setTime(start);
michael@0:         if (isNegative()) {
michael@0:             cal.add(Calendar.WEEK_OF_YEAR, -weeks);
michael@0:             cal.add(Calendar.DAY_OF_WEEK, -days);
michael@0:             cal.add(Calendar.HOUR_OF_DAY, -hours);
michael@0:             cal.add(Calendar.MINUTE, -minutes);
michael@0:             cal.add(Calendar.SECOND, -seconds);
michael@0:         }
michael@0:         else {
michael@0:             cal.add(Calendar.WEEK_OF_YEAR, weeks);
michael@0:             cal.add(Calendar.DAY_OF_WEEK, days);
michael@0:             cal.add(Calendar.HOUR_OF_DAY, hours);
michael@0:             cal.add(Calendar.MINUTE, minutes);
michael@0:             cal.add(Calendar.SECOND, seconds);
michael@0:         }
michael@0:         return cal.getTime();
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Provides a negation of this instance.
michael@0:      * @return a Dur instance that represents a negation of this instance
michael@0:      */
michael@0:     public final Dur negate() {
michael@0:         final Dur negated = new Dur(days, hours, minutes, seconds);
michael@0:         negated.weeks = weeks;
michael@0:         negated.negative = !negative;
michael@0:         return negated;
michael@0:     }
michael@0:     
michael@0:     /**
michael@0:      * Add two durations. Durations may only be added if they are both positive
michael@0:      * or both negative durations.
michael@0:      * @param duration the duration to add to this duration
michael@0:      * @return a new instance representing the sum of the two durations.
michael@0:      */
michael@0:     public final Dur add(final Dur duration) {
michael@0:         if ((!isNegative() && duration.isNegative())
michael@0:                 || (isNegative() && !duration.isNegative())) {
michael@0:             
michael@0:             throw new IllegalArgumentException(
michael@0:                     "Cannot add a negative and a positive duration");
michael@0:         }
michael@0:         
michael@0:         Dur sum = null;
michael@0:         if (weeks > 0 && duration.weeks > 0) {
michael@0:             sum = new Dur(weeks + duration.weeks);
michael@0:         }
michael@0:         else {
michael@0:             int daySum = (weeks > 0) ? weeks * DAYS_PER_WEEK + days : days;
michael@0:             int hourSum = hours;
michael@0:             int minuteSum = minutes;
michael@0:             int secondSum = seconds;
michael@0:             
michael@0:             if ((secondSum + duration.seconds) / SECONDS_PER_MINUTE > 0) {
michael@0:                 minuteSum += (secondSum + duration.seconds) / SECONDS_PER_MINUTE;
michael@0:                 secondSum = (secondSum + duration.seconds) % SECONDS_PER_MINUTE;
michael@0:             }
michael@0:             else {
michael@0:                 secondSum += duration.seconds;
michael@0:             }
michael@0:             
michael@0:             if ((minuteSum + duration.minutes) / MINUTES_PER_HOUR > 0) {
michael@0:                 hourSum += (minuteSum + duration.minutes) / MINUTES_PER_HOUR;
michael@0:                 minuteSum = (minuteSum + duration.minutes) % MINUTES_PER_HOUR;
michael@0:             }
michael@0:             else {
michael@0:                 minuteSum += duration.minutes;
michael@0:             }
michael@0:             
michael@0:             if ((hourSum + duration.hours) / HOURS_PER_DAY > 0) {
michael@0:                 daySum += (hourSum + duration.hours) / HOURS_PER_DAY;
michael@0:                 hourSum = (hourSum + duration.hours) % HOURS_PER_DAY;
michael@0:             }
michael@0:             else {
michael@0:                 hourSum += duration.hours;
michael@0:             }
michael@0:             
michael@0:             daySum += (duration.weeks > 0) ? duration.weeks * DAYS_PER_WEEK
michael@0:                     + duration.days : duration.days;
michael@0:             
michael@0:             sum = new Dur(daySum, hourSum, minuteSum, secondSum);
michael@0:         }
michael@0:         sum.negative = negative;
michael@0:         return sum;
michael@0:     }
michael@0:     
michael@0:     /**
michael@0:      * {@inheritDoc}
michael@0:      */
michael@0:     public final String toString() {
michael@0:         final StringBuffer b = new StringBuffer();
michael@0:         if (negative) {
michael@0:             b.append('-');
michael@0:         }
michael@0:         b.append('P');
michael@0:         if (weeks > 0) {
michael@0:             b.append(weeks);
michael@0:             b.append('W');
michael@0:         }
michael@0:         else {
michael@0:             if (days > 0) {
michael@0:                 b.append(days);
michael@0:                 b.append('D');
michael@0:             }
michael@0:             if (hours > 0 || minutes > 0 || seconds > 0) {
michael@0:                 b.append('T');
michael@0:                 if (hours > 0) {
michael@0:                     b.append(hours);
michael@0:                     b.append('H');
michael@0:                 }
michael@0:                 if (minutes > 0) {
michael@0:                     b.append(minutes);
michael@0:                     b.append('M');
michael@0:                 }
michael@0:                 if (seconds > 0) {
michael@0:                     b.append(seconds);
michael@0:                     b.append('S');
michael@0:                 }
michael@0:             }
michael@0:             // handle case of zero length duration
michael@0:             if ((hours + minutes + seconds + days + weeks) == 0) {
michael@0:                 b.append("T0S");
michael@0:             }
michael@0:         }
michael@0:         return b.toString();
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * {@inheritDoc}
michael@0:      */
michael@0:     public final int compareTo(final Object arg0) {
michael@0:         return compareTo((Dur) arg0);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Compares this duration with another, acording to their length.
michael@0:      * @param arg0 another duration instance
michael@0:      * @return a postive value if this duration is longer, zero if the duration
michael@0:      * lengths are equal, otherwise a negative value
michael@0:      */
michael@0:     public final int compareTo(final Dur arg0) {
michael@0:         int result;
michael@0:         if (isNegative() != arg0.isNegative()) {
michael@0:             // return Boolean.valueOf(isNegative()).compareTo(Boolean.valueOf(arg0.isNegative()));
michael@0:             // for pre-java 1.5 compatibility..
michael@0:             if (isNegative()) {
michael@0:                 return Integer.MIN_VALUE;
michael@0:             }
michael@0:             else {
michael@0:                 return Integer.MAX_VALUE;
michael@0:             }
michael@0:         }
michael@0:         else if (getWeeks() != arg0.getWeeks()) {
michael@0:             result = getWeeks() - arg0.getWeeks();
michael@0:         }
michael@0:         else if (getDays() != arg0.getDays()) {
michael@0:             result = getDays() - arg0.getDays();
michael@0:         }
michael@0:         else if (getHours() != arg0.getHours()) {
michael@0:             result = getHours() - arg0.getHours();
michael@0:         }
michael@0:         else if (getMinutes() != arg0.getMinutes()) {
michael@0:             result = getMinutes() - arg0.getMinutes();
michael@0:         }
michael@0:         else {
michael@0:             result = getSeconds() - arg0.getSeconds();
michael@0:         }
michael@0:         // invert sense of all tests if both durations are negative
michael@0:         if (isNegative()) {
michael@0:             return -result;
michael@0:         }
michael@0:         else {
michael@0:             return result;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * {@inheritDoc}
michael@0:      */
michael@0:     public boolean equals(final Object obj) {
michael@0:         if (obj instanceof Dur) {
michael@0:             return ((Dur) obj).compareTo(this) == 0;
michael@0:         }
michael@0:         return super.equals(obj);
michael@0:     }
michael@0:     
michael@0:     /**
michael@0:      * {@inheritDoc}
michael@0:      */
michael@0:     public int hashCode() {
michael@0:         return new HashCodeBuilder().append(weeks).append(days).append(
michael@0:                 hours).append(minutes).append(seconds).append(negative).toHashCode();
michael@0:     }
michael@0:     
michael@0:     /**
michael@0:      * @return Returns the days.
michael@0:      */
michael@0:     public final int getDays() {
michael@0:         return days;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * @return Returns the hours.
michael@0:      */
michael@0:     public final int getHours() {
michael@0:         return hours;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * @return Returns the minutes.
michael@0:      */
michael@0:     public final int getMinutes() {
michael@0:         return minutes;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * @return Returns the negative.
michael@0:      */
michael@0:     public final boolean isNegative() {
michael@0:         return negative;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * @return Returns the seconds.
michael@0:      */
michael@0:     public final int getSeconds() {
michael@0:         return seconds;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * @return Returns the weeks.
michael@0:      */
michael@0:     public final int getWeeks() {
michael@0:         return weeks;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * @param stream
michael@0:      * @throws IOException
michael@0:      * @throws ClassNotFoundException
michael@0:      */
michael@0:     private void readObject(final java.io.ObjectInputStream stream) throws IOException, ClassNotFoundException {
michael@0:         stream.defaultReadObject();
michael@0:     }
michael@0: }