/*
 * Joda Software License, Version 1.0
 *
 *
 * Copyright (c) 2001-2004 Stephen Colebourne.  
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:  
 *       "This product includes software developed by the
 *        Joda project (http://www.joda.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The name "Joda" must not be used to endorse or promote products
 *    derived from this software without prior written permission. For
 *    written permission, please contact licence@joda.org.
 *
 * 5. Products derived from this software may not be called "Joda",
 *    nor may "Joda" appear in their name, without prior written
 *    permission of the Joda project.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE JODA AUTHORS OR THE PROJECT
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Joda project and was originally 
 * created by Stephen Colebourne <scolebourne@joda.org>. For more
 * information on the Joda project, please see <http://www.joda.org/>.
 */
package org.joda.time.chrono;

import java.util.Locale;

import org.joda.time.DateTimeConstants;
import org.joda.time.DateTimeFieldType;
import org.joda.time.DurationField;
import org.joda.time.DurationFieldType;
import org.joda.time.field.BaseDateTimeField;
import org.joda.time.field.FieldUtils;
import org.joda.time.field.UnsupportedDurationField;

/**
 * Provides time calculations for the era component of time.
 *
 * @author Stephen Colebourne
 * @author Brian S O'Neill
 * @version 1.0
 * @since 1.0
 */
final class GJEraDateTimeField extends BaseDateTimeField {
    
    /** Serialization version */
    private static final long serialVersionUID = 4240986525305515528L;

    private final BaseGJChronology iChronology;

    /**
     * Restricted constructor
     */
    GJEraDateTimeField(BaseGJChronology chronology) {
        super(DateTimeFieldType.era());
        iChronology = chronology;
    }

    public boolean isLenient() {
        return false;
    }

    /**
     * Get the Era component of the specified time instant.
     * 
     * @param instant  the time instant in millis to query.
     */
    public int get(long instant) {
        if (iChronology.getYear(instant) <= 0) {
            return DateTimeConstants.BCE;
        } else {
            return DateTimeConstants.CE;
        }
    }

    protected String getAsText(int fieldValue, Locale locale) {
        return GJLocaleSymbols.forLocale(locale).eraValueToText(fieldValue);
    }

    /**
     * Set the Era component of the specified time instant.
     * 
     * @param instant  the time instant in millis to update.
     * @param era  the era to update the time to.
     * @return the updated time instant.
     * @throws IllegalArgumentException  if era is invalid.
     */
    public long set(long instant, int era) {
        FieldUtils.verifyValueBounds(this, era, DateTimeConstants.BCE, DateTimeConstants.CE);
            
        int oldEra = get(instant);
        if (oldEra != era) {
            int year = iChronology.getYear(instant);
            return iChronology.setYear(instant, -year);
        } else {
            return instant;
        }
    }

    public long set(long instant, String text, Locale locale) {
        return set(instant, GJLocaleSymbols.forLocale(locale).eraTextToValue(text));
    }

    public long roundFloor(long instant) {
        if (get(instant) == DateTimeConstants.CE) {
            return iChronology.setYear(0, 1);
        } else {
            return Long.MIN_VALUE;
        }
    }

    public long roundCeiling(long instant) {
        if (get(instant) == DateTimeConstants.BCE) {
            return iChronology.setYear(0, 1);
        } else {
            return Long.MAX_VALUE;
        }
    }

    public long roundHalfFloor(long instant) {
        // In reality, the era is infinite, so there is no halfway point.
        return roundFloor(instant);
    }

    public long roundHalfCeiling(long instant) {
        // In reality, the era is infinite, so there is no halfway point.
        return roundFloor(instant);
    }

    public long roundHalfEven(long instant) {
        // In reality, the era is infinite, so there is no halfway point.
        return roundFloor(instant);
    }

    public DurationField getDurationField() {
        return UnsupportedDurationField.getInstance(DurationFieldType.eras());
    }

    public DurationField getRangeDurationField() {
        return null;
    }

    public int getMinimumValue() {
        return DateTimeConstants.BCE;
    }

    public int getMaximumValue() {
        return DateTimeConstants.CE;
    }

    public int getMaximumTextLength(Locale locale) {
        return GJLocaleSymbols.forLocale(locale).getEraMaxTextLength();
    }

    /**
     * Serialization singleton
     */
    private Object readResolve() {
        return iChronology.era();
    }
}