// © 2016 and later: Unicode, Inc. and others.

// License & terms of use: http://www.unicode.org/copyright.html

/*

*******************************************************************************

* Copyright (C) 2003-2009,2012,2016 International Business Machines Corporation and

* others. All Rights Reserved.

*******************************************************************************

*

* File JAPANCAL.CPP

*

* Modification History:

*  05/16/2003    srl     copied from buddhcal.cpp

*

*/

#include "unicode/utypes.h"

#if !UCONFIG_NO_FORMATTING

#include "cmemory.h"

#include "japancal.h"

#include "unicode/gregocal.h"

#include "umutex.h"

#include "uassert.h"

//#define U_DEBUG_JCAL

#ifdef U_DEBUG_JCAL

#include <stdio.h>

#endif

U_NAMESPACE_BEGIN

UOBJECT_DEFINE_RTTI_IMPLEMENTATION(JapaneseCalendar)

//  Gregorian date of each emperor's ascension

//  Years are AD, months are 1-based.

static const struct { 

    int16_t year;

    int8_t  month;

    int8_t  day;

} kEraInfo[] =  {

    //  Year  Month Day

    {   645,    6, 19 },   // Taika   0

    {   650,    2, 15 },   // Hakuchi 1

    {   672,    1,  1 },   // Hakuho  2

    {   686,    7, 20 },   // Shucho  3

    {   701,    3, 21 },   // Taiho   4

    {   704,    5, 10 },   // Keiun   5

    {   708,    1, 11 },   // Wado    6

    {   715,    9,  2 },   // Reiki   7

    {   717,   11, 17 },   // Yoro    8

    {   724,    2,  4 },   // Jinki   9

    {   729,    8,  5 },   // Tempyo  10

    {   749,    4, 14 },   // Tempyo-kampo 11

    {   749,    7,  2 },   // Tempyo-shoho 12

    {   757,    8, 18 },   // Tempyo-hoji  13

    {   765,    1,  7 },   // Tempho-jingo 14

    {   767,    8, 16 },   // Jingo-keiun  15

    {   770,   10,  1 },   // Hoki         16

    {   781,    1,  1 },   // Ten-o        17

    {   782,    8, 19 },   // Enryaku      18

    {   806,    5, 18 },   // Daido        19

    {   810,    9, 19 },   // Konin        20

    {   824,    1,  5 },   // Tencho

    {   834,    1,  3 },   // Showa

    {   848,    6, 13 },   // Kajo

    {   851,    4, 28 },   // Ninju

    {   854,   11, 30 },   // Saiko

    {   857,    2, 21 },   // Tennan

    {   859,    4, 15 },   // Jogan

    {   877,    4, 16 },   // Genkei

    {   885,    2, 21 },   // Ninna

    {   889,    4, 27 },   // Kampyo       30

    {   898,    4, 26 },   // Shotai

    {   901,    7, 15 },   // Engi

    {   923,    4, 11 },   // Encho

    {   931,    4, 26 },   // Shohei

    {   938,    5, 22 },   // Tengyo

    {   947,    4, 22 },   // Tenryaku

    {   957,   10, 27 },   // Tentoku

    {   961,    2, 16 },   // Owa

    {   964,    7, 10 },   // Koho

    {   968,    8, 13 },   // Anna        40

    {   970,    3, 25 },   // Tenroku

    {   973,   12, 20 },   // Ten-en

    {   976,    7, 13 },   // Jogen

    {   978,   11, 29 },   // Tengen

    {   983,    4, 15 },   // Eikan

    {   985,    4, 27 },   // Kanna

    {   987,    4,  5 },   // Ei-en

    {   989,    8,  8 },   // Eiso

    {   990,   11,  7 },   // Shoryaku

    {   995,    2, 22 },   // Chotoku      50

    {   999,    1, 13 },   // Choho

    {  1004,    7, 20 },   // Kanko

    {  1012,   12, 25 },   // Chowa

    {  1017,    4, 23 },   // Kannin

    {  1021,    2,  2 },   // Jian

    {  1024,    7, 13 },   // Manju

    {  1028,    7, 25 },   // Chogen

    {  1037,    4, 21 },   // Choryaku

    {  1040,   11, 10 },   // Chokyu

    {  1044,   11, 24 },   // Kantoku      60

    {  1046,    4, 14 },   // Eisho

    {  1053,    1, 11 },   // Tengi

    {  1058,    8, 29 },   // Kohei

    {  1065,    8,  2 },   // Jiryaku

    {  1069,    4, 13 },   // Enkyu

    {  1074,    8, 23 },   // Shoho

    {  1077,   11, 17 },   // Shoryaku

    {  1081,    2, 10 },   // Eiho

    {  1084,    2,  7 },   // Otoku

    {  1087,    4,  7 },   // Kanji       70

    {  1094,   12, 15 },   // Kaho

    {  1096,   12, 17 },   // Eicho

    {  1097,   11, 21 },   // Shotoku

    {  1099,    8, 28 },   // Kowa

    {  1104,    2, 10 },   // Choji

    {  1106,    4,  9 },   // Kasho

    {  1108,    8,  3 },   // Tennin

    {  1110,    7, 13 },   // Ten-ei

    {  1113,    7, 13 },   // Eikyu

    {  1118,    4,  3 },   // Gen-ei      80

    {  1120,    4, 10 },   // Hoan

    {  1124,    4,  3 },   // Tenji

    {  1126,    1, 22 },   // Daiji

    {  1131,    1, 29 },   // Tensho

    {  1132,    8, 11 },   // Chosho

    {  1135,    4, 27 },   // Hoen

    {  1141,    7, 10 },   // Eiji

    {  1142,    4, 28 },   // Koji

    {  1144,    2, 23 },   // Tenyo

    {  1145,    7, 22 },   // Kyuan      90

    {  1151,    1, 26 },   // Ninpei

    {  1154,   10, 28 },   // Kyuju

    {  1156,    4, 27 },   // Hogen

    {  1159,    4, 20 },   // Heiji

    {  1160,    1, 10 },   // Eiryaku

    {  1161,    9,  4 },   // Oho

    {  1163,    3, 29 },   // Chokan

    {  1165,    6,  5 },   // Eiman

    {  1166,    8, 27 },   // Nin-an

    {  1169,    4,  8 },   // Kao       100

    {  1171,    4, 21 },   // Shoan

    {  1175,    7, 28 },   // Angen

    {  1177,    8,  4 },   // Jisho

    {  1181,    7, 14 },   // Yowa

    {  1182,    5, 27 },   // Juei

    {  1184,    4, 16 },   // Genryuku

    {  1185,    8, 14 },   // Bunji

    {  1190,    4, 11 },   // Kenkyu

    {  1199,    4, 27 },   // Shoji

    {  1201,    2, 13 },   // Kennin     110

    {  1204,    2, 20 },   // Genkyu

    {  1206,    4, 27 },   // Ken-ei

    {  1207,   10, 25 },   // Shogen

    {  1211,    3,  9 },   // Kenryaku

    {  1213,   12,  6 },   // Kenpo

    {  1219,    4, 12 },   // Shokyu

    {  1222,    4, 13 },   // Joo

    {  1224,   11, 20 },   // Gennin

    {  1225,    4, 20 },   // Karoku

    {  1227,   12, 10 },   // Antei      120

    {  1229,    3,  5 },   // Kanki

    {  1232,    4,  2 },   // Joei

    {  1233,    4, 15 },   // Tempuku

    {  1234,   11,  5 },   // Bunryaku

    {  1235,    9, 19 },   // Katei

    {  1238,   11, 23 },   // Ryakunin

    {  1239,    2,  7 },   // En-o

    {  1240,    7, 16 },   // Ninji

    {  1243,    2, 26 },   // Kangen

    {  1247,    2, 28 },   // Hoji      130

    {  1249,    3, 18 },   // Kencho

    {  1256,   10,  5 },   // Kogen

    {  1257,    3, 14 },   // Shoka

    {  1259,    3, 26 },   // Shogen

    {  1260,    4, 13 },   // Bun-o

    {  1261,    2, 20 },   // Kocho

    {  1264,    2, 28 },   // Bun-ei

    {  1275,    4, 25 },   // Kenji

    {  1278,    2, 29 },   // Koan

    {  1288,    4, 28 },   // Shoo      140

    {  1293,    8, 55 },   // Einin

    {  1299,    4, 25 },   // Shoan

    {  1302,   11, 21 },   // Kengen

    {  1303,    8,  5 },   // Kagen

    {  1306,   12, 14 },   // Tokuji

    {  1308,   10,  9 },   // Enkei

    {  1311,    4, 28 },   // Ocho

    {  1312,    3, 20 },   // Showa

    {  1317,    2,  3 },   // Bunpo

    {  1319,    4, 28 },   // Geno      150

    {  1321,    2, 23 },   // Genkyo

    {  1324,   12,  9 },   // Shochu

    {  1326,    4, 26 },   // Kareki

    {  1329,    8, 29 },   // Gentoku

    {  1331,    8,  9 },   // Genko

    {  1334,    1, 29 },   // Kemmu

    {  1336,    2, 29 },   // Engen

    {  1340,    4, 28 },   // Kokoku

    {  1346,   12,  8 },   // Shohei

    {  1370,    7, 24 },   // Kentoku       160

    {  1372,    4,  1 },   // Bunch\u0169

    {  1375,    5, 27 },   // Tenju

    {  1379,    3, 22 },   // Koryaku

    {  1381,    2, 10 },   // Kowa

    {  1384,    4, 28 },   // Gench\u0169

    {  1384,    2, 27 },   // Meitoku

    {  1387,    8, 23 },   // Kakei

    {  1389,    2,  9 },   // Koo

    {  1390,    3, 26 },   // Meitoku

    {  1394,    7,  5 },   // Oei           170

    {  1428,    4, 27 },   // Shocho

    {  1429,    9,  5 },   // Eikyo

    {  1441,    2, 17 },   // Kakitsu

    {  1444,    2,  5 },   // Bun-an

    {  1449,    7, 28 },   // Hotoku

    {  1452,    7, 25 },   // Kyotoku

    {  1455,    7, 25 },   // Kosho

    {  1457,    9, 28 },   // Choroku

    {  1460,   12, 21 },   // Kansho

    {  1466,    2, 28 },   // Bunsho        180

    {  1467,    3,  3 },   // Onin

    {  1469,    4, 28 },   // Bunmei

    {  1487,    7, 29 },   // Chokyo

    {  1489,    8, 21 },   // Entoku

    {  1492,    7, 19 },   // Meio

    {  1501,    2, 29 },   // Bunki

    {  1504,    2, 30 },   // Eisho

    {  1521,    8, 23 },   // Taiei

    {  1528,    8, 20 },   // Kyoroku

    {  1532,    7, 29 },   // Tenmon       190

    {  1555,   10, 23 },   // Koji

    {  1558,    2, 28 },   // Eiroku

    {  1570,    4, 23 },   // Genki

    {  1573,    7, 28 },   // Tensho

    {  1592,   12,  8 },   // Bunroku

    {  1596,   10, 27 },   // Keicho

    {  1615,    7, 13 },   // Genwa

    {  1624,    2, 30 },   // Kan-ei

    {  1644,   12, 16 },   // Shoho

    {  1648,    2, 15 },   // Keian       200

    {  1652,    9, 18 },   // Shoo

    {  1655,    4, 13 },   // Meiryaku

    {  1658,    7, 23 },   // Manji

    {  1661,    4, 25 },   // Kanbun

    {  1673,    9, 21 },   // Enpo

    {  1681,    9, 29 },   // Tenwa

    {  1684,    2, 21 },   // Jokyo

    {  1688,    9, 30 },   // Genroku

    {  1704,    3, 13 },   // Hoei

    {  1711,    4, 25 },   // Shotoku      210

    {  1716,    6, 22 },   // Kyoho

    {  1736,    4, 28 },   // Genbun

    {  1741,    2, 27 },   // Kanpo

    {  1744,    2, 21 },   // Enkyo

    {  1748,    7, 12 },   // Kan-en

    {  1751,   10, 27 },   // Horyaku

    {  1764,    6,  2 },   // Meiwa

    {  1772,   11, 16 },   // An-ei

    {  1781,    4,  2 },   // Tenmei

    {  1789,    1, 25 },   // Kansei      220

    {  1801,    2,  5 },   // Kyowa

    {  1804,    2, 11 },   // Bunka

    {  1818,    4, 22 },   // Bunsei

    {  1830,   12, 10 },   // Tenpo

    {  1844,   12,  2 },   // Koka

    {  1848,    2, 28 },   // Kaei

    {  1854,   11, 27 },   // Ansei

    {  1860,    3, 18 },   // Man-en

    {  1861,    2, 19 },   // Bunkyu

    {  1864,    2, 20 },   // Genji        230

    {  1865,    4,  7 },   // Keio     231

    {  1868,    9,  8 },   // Meiji    232

    {  1912,    7, 30 },   // Taisho   233

    {  1926,   12, 25 },   // Showa    234

    {  1989,    1,  8 }   // Heisei    235

};

#define kEraCount UPRV_LENGTHOF(kEraInfo)

/**

 * The current era, for reference. 

 */

static const int32_t kCurrentEra = (kEraCount-1);  // int32_t to match the calendar field type

static const int32_t kGregorianEpoch = 1970;    // used as the default value of EXTENDED_YEAR

/* Some platforms don't like to export constants, like old Palm OS and some z/OS configurations. */

uint32_t JapaneseCalendar::getCurrentEra() {

    return kCurrentEra;

}

JapaneseCalendar::JapaneseCalendar(const Locale& aLocale, UErrorCode& success)

:   GregorianCalendar(aLocale, success)

{

    setTimeInMillis(getNow(), success); // Call this again now that the vtable is set up properly.

}

JapaneseCalendar::~JapaneseCalendar()

{

}

JapaneseCalendar::JapaneseCalendar(const JapaneseCalendar& source)

: GregorianCalendar(source)

{

}

JapaneseCalendar& JapaneseCalendar::operator= ( const JapaneseCalendar& right)

{

    GregorianCalendar::operator=(right);

    return *this;

}

Calendar* JapaneseCalendar::clone(void) const

{

    return new JapaneseCalendar(*this);

}

const char *JapaneseCalendar::getType() const

{

    return "japanese";

}

int32_t JapaneseCalendar::getDefaultMonthInYear(int32_t eyear) 

{

    int32_t era = internalGetEra();

    // TODO do we assume we can trust 'era'?  What if it is denormalized?

    int32_t month = 0;

    // Find out if we are at the edge of an era

    if(eyear == kEraInfo[era].year) {

        // Yes, we're in the first year of this era.

        return kEraInfo[era].month-1;

    }

    return month;

}

int32_t JapaneseCalendar::getDefaultDayInMonth(int32_t eyear, int32_t month) 

{

    int32_t era = internalGetEra();

    int32_t day = 1;

    if(eyear == kEraInfo[era].year) {

        if(month == (kEraInfo[era].month-1)) {

            return kEraInfo[era].day;

        }

    }

    return day;

}

int32_t JapaneseCalendar::internalGetEra() const

{

    return internalGet(UCAL_ERA, kCurrentEra);

}

int32_t JapaneseCalendar::handleGetExtendedYear()

{

    // EXTENDED_YEAR in JapaneseCalendar is a Gregorian year

    // The default value of EXTENDED_YEAR is 1970 (Showa 45)

    int32_t year;

    if (newerField(UCAL_EXTENDED_YEAR, UCAL_YEAR) == UCAL_EXTENDED_YEAR &&

        newerField(UCAL_EXTENDED_YEAR, UCAL_ERA) == UCAL_EXTENDED_YEAR) {

            year = internalGet(UCAL_EXTENDED_YEAR, kGregorianEpoch);

        } else {

            // Subtract one because year starts at 1

            year = internalGet(UCAL_YEAR) + kEraInfo[internalGetEra()].year - 1;

        }

        return year;

}

void JapaneseCalendar::handleComputeFields(int32_t julianDay, UErrorCode& status)

{

    //Calendar::timeToFields(theTime, quick, status);

    GregorianCalendar::handleComputeFields(julianDay, status);

    int32_t year = internalGet(UCAL_EXTENDED_YEAR); // Gregorian year

    int32_t low = 0;

    // Short circuit for recent years.  Most modern computations will

    // occur in the current era and won't require the binary search.

    // Note that if the year is == the current era year, then we use

    // the binary search to handle the month/dom comparison.

#ifdef U_DEBUG_JCAL

    fprintf(stderr, "==  %d \n", year);

#endif

    if (year > kEraInfo[kCurrentEra].year) {

        low = kCurrentEra;

#ifdef U_DEBUG_JCAL

        fprintf(stderr, " low=%d (special)\n", low);

#endif

    } else {

        // Binary search

        int32_t high = kEraCount;

#ifdef U_DEBUG_JCAL

        fprintf(stderr, " high=%d\n", high);

#endif

        while (low < high - 1) {

            int32_t i = (low + high) / 2;

            int32_t diff = year - kEraInfo[i].year;

#ifdef U_DEBUG_JCAL

            fprintf(stderr, "  d=%d   low=%d, high=%d. Considering %d:M%d D%d Y%d. { we are ?:M%d D%d Y%d }\n",

                diff,low, high, i, kEraInfo[i].month-1, kEraInfo[i].day,  kEraInfo[i].year, internalGet(UCAL_MONTH), internalGet(UCAL_DATE),year);

#endif

            // If years are the same, then compare the months, and if those

            // are the same, compare days of month.  In the ERAS array

            // months are 1-based for easier maintenance.

            if (diff == 0) {

                diff = internalGet(UCAL_MONTH) - (kEraInfo[i].month - 1);

#ifdef U_DEBUG_JCAL

                fprintf(stderr, "diff now %d (M)  = %d - %d - 1\n", diff, internalGet(UCAL_MONTH), kEraInfo[i].month);

#endif

                if (diff == 0) {

                    diff = internalGet(UCAL_DATE) - kEraInfo[i].day;

#ifdef U_DEBUG_JCAL

                    fprintf(stderr, "diff now %d (D)\n", diff);

#endif

                }

            }

            if (diff >= 0) {

                low = i;

            } else {

                high = i;

            }

#ifdef U_DEBUG_JCAL

            fprintf(stderr, ". low=%d, high=%d, i=%d, diff=%d.. %d\n", low, high, i, diff, year);

#endif

        }

    }

#ifdef U_DEBUG_JCAL

    fprintf(stderr, "  low[era]=%d,.. %d\n", low, year);

#endif

    // Now we've found the last era that starts before this date, so

    // adjust the year to count from the start of that era.  Note that

    // all dates before the first era will fall into the first era by

    // the algorithm.

    internalSet(UCAL_ERA, low);

    internalSet(UCAL_YEAR, year - kEraInfo[low].year + 1);

#ifdef U_DEBUG_JCAL

    fprintf(stderr, "  Set ERA=%d, year=%d\n", low, year-kEraInfo[low].year+1);

#endif

}

/*

Disable pivoting 

*/

UBool JapaneseCalendar::haveDefaultCentury() const

{

    return FALSE;

}

UDate JapaneseCalendar::defaultCenturyStart() const

{

    return 0;// WRONG

}

int32_t JapaneseCalendar::defaultCenturyStartYear() const

{

    return 0;

}

int32_t JapaneseCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const

{

    switch(field) {

    case UCAL_ERA:

        if (limitType == UCAL_LIMIT_MINIMUM || limitType == UCAL_LIMIT_GREATEST_MINIMUM) {

            return 0;

        }

        return kCurrentEra;

    case UCAL_YEAR:

        {

            switch (limitType) {

            case UCAL_LIMIT_MINIMUM:

            case UCAL_LIMIT_GREATEST_MINIMUM:

                return 1;

            case UCAL_LIMIT_LEAST_MAXIMUM:

                return 1;

            case  UCAL_LIMIT_COUNT: //added to avoid warning

            case UCAL_LIMIT_MAXIMUM:

                return GregorianCalendar::handleGetLimit(UCAL_YEAR, UCAL_LIMIT_MAXIMUM) - kEraInfo[kCurrentEra].year;

            default:

                return 1;    // Error condition, invalid limitType

            }

        }

    default:

        return GregorianCalendar::handleGetLimit(field,limitType);

    }

}

int32_t JapaneseCalendar::getActualMaximum(UCalendarDateFields field, UErrorCode& status) const {

    if (field == UCAL_YEAR) {

        int32_t era = get(UCAL_ERA, status);

        if (U_FAILURE(status)) {

            return 0; // error case... any value

        }

        if (era == kCurrentEra) {

            // TODO: Investigate what value should be used here - revisit after 4.0.

            return handleGetLimit(UCAL_YEAR, UCAL_LIMIT_MAXIMUM);

        } else {

            int32_t nextEraYear = kEraInfo[era + 1].year;

            int32_t nextEraMonth = kEraInfo[era + 1].month;

            int32_t nextEraDate = kEraInfo[era + 1].day;

            int32_t maxYear = nextEraYear - kEraInfo[era].year + 1; // 1-base

            if (nextEraMonth == 1 && nextEraDate == 1) {

                // Subtract 1, because the next era starts at Jan 1

                maxYear--;

            }

            return maxYear;

        }

    }

    return GregorianCalendar::getActualMaximum(field, status);

}

U_NAMESPACE_END

#endif