/*

 * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package sun.util;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.util.GregorianCalendar;

import java.util.Locale;

import java.util.Map;

import java.util.TimeZone;

import sun.util.locale.provider.CalendarDataUtility;

public class BuddhistCalendar extends GregorianCalendar {

//////////////////

// Class Variables

//////////////////

    private static final long serialVersionUID = -8527488697350388578L;

    private static final int BUDDHIST_YEAR_OFFSET = 543;

///////////////

// Constructors

///////////////

    /**

     * Constructs a default BuddhistCalendar using the current time

     * in the default time zone with the default locale.

     */

    public BuddhistCalendar() {

        super();

    }

    /**

     * Constructs a BuddhistCalendar based on the current time

     * in the given time zone with the default locale.

     * @param zone the given time zone.

     */

    public BuddhistCalendar(TimeZone zone) {

        super(zone);

    }

    /**

     * Constructs a BuddhistCalendar based on the current time

     * in the default time zone with the given locale.

     * @param aLocale the given locale.

     */

    public BuddhistCalendar(Locale aLocale) {

        super(aLocale);

    }

    /**

     * Constructs a BuddhistCalendar based on the current time

     * in the given time zone with the given locale.

     * @param zone the given time zone.

     * @param aLocale the given locale.

     */

    public BuddhistCalendar(TimeZone zone, Locale aLocale) {

        super(zone, aLocale);

    }

/////////////////

// Public methods

/////////////////

    /**

     * Returns {@code "buddhist"} as the calendar type of this Calendar.

     */

    @Override

    public String getCalendarType() {

        return "buddhist";

    }

    /**

     * Compares this BuddhistCalendar to an object reference.

     * @param obj the object reference with which to compare

     * @return true if this object is equal to <code>obj</code>; false otherwise

     */

    @Override

    public boolean equals(Object obj) {

        return obj instanceof BuddhistCalendar

            && super.equals(obj);

    }

    /**

     * Override hashCode.

     * Generates the hash code for the BuddhistCalendar object

     */

    @Override

    public int hashCode() {

        return super.hashCode() ^ BUDDHIST_YEAR_OFFSET;

    }

    /**

     * Gets the value for a given time field.

     * @param field the given time field.

     * @return the value for the given time field.

     */

    @Override

    public int get(int field)

    {

        if (field == YEAR) {

            return super.get(field) + yearOffset;

        }

        return super.get(field);

    }

    /**

     * Sets the time field with the given value.

     * @param field the given time field.

     * @param value the value to be set for the given time field.

     */

    @Override

    public void set(int field, int value)

    {

        if (field == YEAR) {

            super.set(field, value - yearOffset);

        } else {

            super.set(field, value);

        }

    }

    /**

     * Adds the specified (signed) amount of time to the given time field.

     * @param field the time field.

     * @param amount the amount of date or time to be added to the field.

     */

    @Override

    public void add(int field, int amount)

    {

        int savedYearOffset = yearOffset;

        // To let the superclass calculate date-time values correctly,

        // temporarily make this GregorianCalendar.

        yearOffset = 0;

        try {

            super.add(field, amount);

        } finally {

            yearOffset = savedYearOffset;

        }

    }

    /**

     * Add to field a signed amount without changing larger fields.

     * A negative roll amount means to subtract from field without changing

     * larger fields.

     * @param field the time field.

     * @param amount the signed amount to add to <code>field</code>.

     */

    @Override

    public void roll(int field, int amount)

    {

        int savedYearOffset = yearOffset;

        // To let the superclass calculate date-time values correctly,

        // temporarily make this GregorianCalendar.

        yearOffset = 0;

        try {

            super.roll(field, amount);

        } finally {

            yearOffset = savedYearOffset;

        }

    }

    @Override

    public String getDisplayName(int field, int style, Locale locale) {

        if (field != ERA) {

            return super.getDisplayName(field, style, locale);

        }

        return CalendarDataUtility.retrieveFieldValueName("buddhist", field, get(field), style, locale);

    }

    @Override

    public Map<String,Integer> getDisplayNames(int field, int style, Locale locale) {

        if (field != ERA) {

            return super.getDisplayNames(field, style, locale);

        }

        return CalendarDataUtility.retrieveFieldValueNames("buddhist", field, style, locale);

    }

    /**

     * Returns the maximum value that this field could have, given the

     * current date.  For example, with the date "Feb 3, 2540" and the

     * <code>DAY_OF_MONTH</code> field, the actual maximum is 28; for

     * "Feb 3, 2539" it is 29.

     *

     * @param field the field to determine the maximum of

     * @return the maximum of the given field for the current date of this Calendar

     */

    @Override

    public int getActualMaximum(int field) {

        int savedYearOffset = yearOffset;

        // To let the superclass calculate date-time values correctly,

        // temporarily make this GregorianCalendar.

        yearOffset = 0;

        try {

            return super.getActualMaximum(field);

        } finally {

            yearOffset = savedYearOffset;

        }

    }

    @Override

    @SuppressWarnings("empty-statement")

    public String toString() {

        // The super class produces a String with the Gregorian year

        // value (or '?')

        String s = super.toString();

        // If the YEAR field is UNSET, then return the Gregorian string.

        if (!isSet(YEAR)) {

            return s;

        }

        final String yearField = "YEAR=";

        int p = s.indexOf(yearField);

        // If the string doesn't include the year value for some

        // reason, then return the Gregorian string.

        if (p == -1) {

            return s;

        }

        p += yearField.length();

        StringBuilder sb = new StringBuilder(s.length() + 10);

        sb.append(s, 0, p);

        // Skip the year number

        while (Character.isDigit(s.charAt(p++)))

            ;

        int year = internalGet(YEAR) + BUDDHIST_YEAR_OFFSET;

        sb.append(year).append(s, p - 1, s.length());

        return sb.toString();

    }

    private transient int yearOffset = BUDDHIST_YEAR_OFFSET;

    private void readObject(ObjectInputStream stream)

        throws IOException, ClassNotFoundException {

        stream.defaultReadObject();

        yearOffset = BUDDHIST_YEAR_OFFSET;

    }

}