/*

 * Copyright (c) 1997, 2016, 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.

 *

 * 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.

 */

/**

 * @test

 * @bug 4033662

 * @summary test for limit on Calendar

 * @library /java/text/testlib

 * @run main CalendarLimitTest -verbose

 */

import java.util.*;

import java.text.*;

/**

 * This test verifies the behavior of Calendar around the very earliest limits

 * which it can handle.  It also verifies the behavior for large values of millis.

 *

 * Note: There used to be a limit, due to a bug, for early times.  There is

 * currently no limit.

 *

 * March 17, 1998: Added code to make sure big + dates are big + AD years, and

 * big - dates are big + BC years.

 */

public class CalendarLimitTest extends IntlTest

{

    // This number determined empirically; this is the old limit,

    // which we test for to make sure it isn't there anymore.

    static final long EARLIEST_SUPPORTED_MILLIS = -210993120000000L;

    static final int EPOCH_JULIAN_DAY   = 2440588; // Jaunary 1, 1970 (Gregorian)

    static final int JAN_1_1_JULIAN_DAY = 1721426; // January 1, year 1 (Gregorian)

    // Useful millisecond constants

    static final int  ONE_SECOND = 1000;

    static final int  ONE_MINUTE = 60*ONE_SECOND;

    static final int  ONE_HOUR   = 60*ONE_MINUTE;

    static final int  ONE_DAY    = 24*ONE_HOUR;

    static final int  ONE_WEEK   = 7*ONE_DAY;

    static final long ONE_YEAR   = (long)(365.2425 * ONE_DAY);

    static long ORIGIN; // This is the *approximate* point at which BC switches to AD

    public static void main(String argv[]) throws Exception {

        Locale locale = Locale.getDefault();

        if (!TestUtils.usesGregorianCalendar(locale)) {

            System.out.println("Skipping this test because locale is " + locale);

            return;

        }

        new CalendarLimitTest().run(argv);

    }

    /**

     * Converts Julian day to time as milliseconds.

     * @param julian the given Julian day number.

     * @return time as milliseconds.

     */

    private static final long julianDayToMillis(long julian) {

        return (julian - EPOCH_JULIAN_DAY) * ONE_DAY;

    }

    /**

     * Verify that the given time is processed without problem.

     * @return the adjust year, with 0 = 1 BC, -1 = 2 BC, etc.

     */

    int test(long millis, Calendar cal, DateFormat fmt)

    {

        Exception exception = null;

        String theDate = "";

        try {

            Date d= new Date(millis);

            cal.setTime(d);

            theDate = fmt.format(d);

        }

        catch (IllegalArgumentException e) {

            exception = e;

        }

        String s = "0x" + Long.toHexString(millis) + " " + theDate;

        int era=cal.get(Calendar.ERA), year=cal.get(Calendar.YEAR),

            dom=cal.get(Calendar.DATE), mon=cal.get(Calendar.MONTH);

        cal.clear();

        cal.set(year, mon, dom);

        cal.set(Calendar.ERA, era);

        Date rt = cal.getTime();

        boolean ok = true;

        if (exception != null) {

            errln("FAIL: Exception " + s);

            ok = false;

        }

        if (((millis >= ORIGIN) && (era != GregorianCalendar.AD)) ||

                 ((millis < ORIGIN) && (era != GregorianCalendar.BC)) ||

                 (year < 1)) {

            errln("FAIL: Bad year/era " + s);

            ok = false;

        }

        if (dom<1 || dom>31) {

            errln("FAIL: Bad DOM " + s);

            ok = false;

        }

        if (Math.abs(millis - rt.getTime()) > ONE_DAY) {

            errln("FAIL: RT fail " + s + " -> 0x" +

                  Long.toHexString(rt.getTime()) + " " +

                  fmt.format(rt));

            ok = false;

        }

        if (ok) logln(s);

        if (era==GregorianCalendar.BC) year = 1-year;

        return year;

    }

    public void TestCalendarLimit()

    {

        ORIGIN = julianDayToMillis(JAN_1_1_JULIAN_DAY);

        Calendar cal = Calendar.getInstance();

        // You must set the time zone to GMT+0 or the edge cases like

        // Long.MIN_VALUE, Long.MAX_VALUE, and right around the threshold

        // won't work, since before converting to fields the calendar code

        // will add the offset for the zone.

        cal.setTimeZone(TimeZone.getTimeZone("Africa/Casablanca"));

        DateFormat dateFormat = DateFormat.getDateInstance();

        dateFormat.setCalendar(cal); // Make sure you do this -- same reason as above

        ((SimpleDateFormat)dateFormat).applyPattern("MMM d, yyyy G");

        // Don't expect any failure for positive longs

        int lastYear=0;

        boolean first=true;

        for (long m = Long.MAX_VALUE; m > 0; m >>= 1)

        {

            int y = test(m, cal, dateFormat);

            if (!first && y > lastYear)

                errln("FAIL: Years should be decreasing " + lastYear + " " + y);

            first = false;

            lastYear = y;

        }

        // Expect failures for negative millis below threshold

        first = true;

        for (long m = Long.MIN_VALUE; m < 0; m /= 2) // Don't use m >>= 1

        {

            int y = test(m, cal, dateFormat);

            if (!first && y < lastYear)

                errln("FAIL: Years should be increasing " + lastYear + " " + y);

            first = false;

            lastYear = y;

        }

        // Test right around the threshold

        test(EARLIEST_SUPPORTED_MILLIS,   cal, dateFormat);

        test(EARLIEST_SUPPORTED_MILLIS-1, cal, dateFormat);

        // Test a date that should work

        test(Long.MIN_VALUE + ONE_DAY,    cal, dateFormat);

        // Try hours in the earliest day or two

        // JUST FOR DEBUGGING:

        if (false) {

            ((SimpleDateFormat)dateFormat).applyPattern("H:mm MMM d, yyyy G");

            for (int dom=2; dom<=3; ++dom) {

                for (int h=0; h<24; ++h) {

                    cal.clear();

                    cal.set(Calendar.ERA, GregorianCalendar.BC);

                    cal.set(292269055, Calendar.DECEMBER, dom, h, 0);

                    Date d = cal.getTime();

                    cal.setTime(d);

                    logln("" + h + ":00 Dec "+dom+", 292269055 BC -> " +

                          Long.toHexString(d.getTime()) + " -> " +

                          dateFormat.format(cal.getTime()));

                }

            }

            // Other way

            long t = 0x80000000018c5c00L; // Dec 3, 292269055 BC

            while (t<0) {

                cal.setTime(new Date(t));

                logln("0x" + Long.toHexString(t) + " -> " +

                      dateFormat.format(cal.getTime()));

                t -= ONE_HOUR;

            }

        }

    }

}

//eof