/*
******************************************************************************
- * Copyright (C) 2003-2004, International Business Machines Corporation and *
- * others. All Rights Reserved. *
+ * Copyright (C) 2007-2011, International Business Machines Corporation
+ * and others. All Rights Reserved.
******************************************************************************
*
+ * File CHNSECAL.CPP
*
- ******************************************************************************
+ * Modification History:
+ *
+ * Date Name Description
+ * 9/18/2007 ajmacher ported from java ChineseCalendar
+ *****************************************************************************
*/
+
#include "chnsecal.h"
-// Placeholder for now until the implementation can be finished.
+#if !UCONFIG_NO_FORMATTING
+
+#include "umutex.h"
+#include <float.h>
+#include "gregoimp.h" // Math
+#include "astro.h" // CalendarAstronomer
+#include "uhash.h"
+#include "ucln_in.h"
+
+// Debugging
+#ifdef U_DEBUG_CHNSECAL
+# include <stdio.h>
+# include <stdarg.h>
+static void debug_chnsecal_loc(const char *f, int32_t l)
+{
+ fprintf(stderr, "%s:%d: ", f, l);
+}
+
+static void debug_chnsecal_msg(const char *pat, ...)
+{
+ va_list ap;
+ va_start(ap, pat);
+ vfprintf(stderr, pat, ap);
+ fflush(stderr);
+}
+// must use double parens, i.e.: U_DEBUG_CHNSECAL_MSG(("four is: %d",4));
+#define U_DEBUG_CHNSECAL_MSG(x) {debug_chnsecal_loc(__FILE__,__LINE__);debug_chnsecal_msg x;}
+#else
+#define U_DEBUG_CHNSECAL_MSG(x)
+#endif
+
+
+// --- The cache --
+static UMTX astroLock = 0; // pod bay door lock
+static icu::CalendarAstronomer *gChineseCalendarAstro = NULL;
+static icu::CalendarCache *gChineseCalendarWinterSolsticeCache = NULL;
+static icu::CalendarCache *gChineseCalendarNewYearCache = NULL;
+
+/**
+ * The start year of the Chinese calendar, the 61st year of the reign
+ * of Huang Di. Some sources use the first year of his reign,
+ * resulting in EXTENDED_YEAR values 60 years greater and ERA (cycle)
+ * values one greater.
+ */
+static const int32_t CHINESE_EPOCH_YEAR = -2636; // Gregorian year
+
+/**
+ * The offset from GMT in milliseconds at which we perform astronomical
+ * computations. Some sources use a different historically accurate
+ * offset of GMT+7:45:40 for years before 1929; we do not do this.
+ */
+static const double CHINA_OFFSET = 8 * kOneHour;
+
+/**
+ * Value to be added or subtracted from the local days of a new moon to
+ * get close to the next or prior new moon, but not cross it. Must be
+ * >= 1 and < CalendarAstronomer.SYNODIC_MONTH.
+ */
+static const int32_t SYNODIC_GAP = 25;
+
+
+U_CDECL_BEGIN
+static UBool calendar_chinese_cleanup(void) {
+ if (gChineseCalendarAstro) {
+ delete gChineseCalendarAstro;
+ gChineseCalendarAstro = NULL;
+ }
+ if (gChineseCalendarWinterSolsticeCache) {
+ delete gChineseCalendarWinterSolsticeCache;
+ gChineseCalendarWinterSolsticeCache = NULL;
+ }
+ if (gChineseCalendarNewYearCache) {
+ delete gChineseCalendarNewYearCache;
+ gChineseCalendarNewYearCache = NULL;
+ }
+ umtx_destroy(&astroLock);
+ return TRUE;
+}
+U_CDECL_END
+
+U_NAMESPACE_BEGIN
+
+
+// Implementation of the ChineseCalendar class
+
+
+//-------------------------------------------------------------------------
+// Constructors...
+//-------------------------------------------------------------------------
+
+
+Calendar* ChineseCalendar::clone() const {
+ return new ChineseCalendar(*this);
+}
+
+ChineseCalendar::ChineseCalendar(const Locale& aLocale, UErrorCode& success)
+: Calendar(TimeZone::createDefault(), aLocale, success)
+{
+ isLeapYear = FALSE;
+ setTimeInMillis(getNow(), success); // Call this again now that the vtable is set up properly.
+}
+
+ChineseCalendar::ChineseCalendar(const ChineseCalendar& other) : Calendar(other) {
+ isLeapYear = other.isLeapYear;
+}
+
+ChineseCalendar::~ChineseCalendar()
+{
+}
+
+const char *ChineseCalendar::getType() const {
+ return "chinese";
+}
+
+//-------------------------------------------------------------------------
+// Minimum / Maximum access functions
+//-------------------------------------------------------------------------
+
+
+static const int32_t LIMITS[UCAL_FIELD_COUNT][4] = {
+ // Minimum Greatest Least Maximum
+ // Minimum Maximum
+ { 1, 1, 83333, 83333}, // ERA
+ { 1, 1, 60, 60}, // YEAR
+ { 0, 0, 11, 11}, // MONTH
+ { 1, 1, 50, 55}, // WEEK_OF_YEAR
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // WEEK_OF_MONTH
+ { 1, 1, 29, 30}, // DAY_OF_MONTH
+ { 1, 1, 353, 385}, // DAY_OF_YEAR
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DAY_OF_WEEK
+ { -1, -1, 5, 5}, // DAY_OF_WEEK_IN_MONTH
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // AM_PM
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR_OF_DAY
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MINUTE
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // SECOND
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECOND
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // ZONE_OFFSET
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DST_OFFSET
+ { -5000000, -5000000, 5000000, 5000000}, // YEAR_WOY
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DOW_LOCAL
+ { -5000000, -5000000, 5000000, 5000000}, // EXTENDED_YEAR
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // JULIAN_DAY
+ {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECONDS_IN_DAY
+ { 0, 0, 1, 1}, // IS_LEAP_MONTH
+};
+
+
+/**
+* @draft ICU 2.4
+*/
+int32_t ChineseCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const {
+ return LIMITS[field][limitType];
+}
+
+
+//----------------------------------------------------------------------
+// Calendar framework
+//----------------------------------------------------------------------
+
+/**
+ * Implement abstract Calendar method to return the extended year
+ * defined by the current fields. This will use either the ERA and
+ * YEAR field as the cycle and year-of-cycle, or the EXTENDED_YEAR
+ * field as the continuous year count, depending on which is newer.
+ * @stable ICU 2.8
+ */
+int32_t ChineseCalendar::handleGetExtendedYear() {
+ int32_t year;
+ if (newestStamp(UCAL_ERA, UCAL_YEAR, kUnset) <= fStamp[UCAL_EXTENDED_YEAR]) {
+ year = internalGet(UCAL_EXTENDED_YEAR, 1); // Default to year 1
+ } else {
+ int32_t cycle = internalGet(UCAL_ERA, 1) - 1; // 0-based cycle
+ year = cycle * 60 + internalGet(UCAL_YEAR, 1);
+ }
+ return year;
+}
+
+/**
+ * Override Calendar method to return the number of days in the given
+ * extended year and month.
+ *
+ * <p>Note: This method also reads the IS_LEAP_MONTH field to determine
+ * whether or not the given month is a leap month.
+ * @stable ICU 2.8
+ */
+int32_t ChineseCalendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const {
+ int32_t thisStart = handleComputeMonthStart(extendedYear, month, TRUE) -
+ kEpochStartAsJulianDay + 1; // Julian day -> local days
+ int32_t nextStart = newMoonNear(thisStart + SYNODIC_GAP, TRUE);
+ return nextStart - thisStart;
+}
+
+/**
+ * Override Calendar to compute several fields specific to the Chinese
+ * calendar system. These are:
+ *
+ * <ul><li>ERA
+ * <li>YEAR
+ * <li>MONTH
+ * <li>DAY_OF_MONTH
+ * <li>DAY_OF_YEAR
+ * <li>EXTENDED_YEAR</ul>
+ *
+ * The DAY_OF_WEEK and DOW_LOCAL fields are already set when this
+ * method is called. The getGregorianXxx() methods return Gregorian
+ * calendar equivalents for the given Julian day.
+ *
+ * <p>Compute the ChineseCalendar-specific field IS_LEAP_MONTH.
+ * @stable ICU 2.8
+ */
+void ChineseCalendar::handleComputeFields(int32_t julianDay, UErrorCode &/*status*/) {
+
+ computeChineseFields(julianDay - kEpochStartAsJulianDay, // local days
+ getGregorianYear(), getGregorianMonth(),
+ TRUE); // set all fields
+}
+
+/**
+ * Field resolution table that incorporates IS_LEAP_MONTH.
+ */
+const UFieldResolutionTable ChineseCalendar::CHINESE_DATE_PRECEDENCE[] =
+{
+ {
+ { UCAL_DAY_OF_MONTH, kResolveSTOP },
+ { UCAL_WEEK_OF_YEAR, UCAL_DAY_OF_WEEK, kResolveSTOP },
+ { UCAL_WEEK_OF_MONTH, UCAL_DAY_OF_WEEK, kResolveSTOP },
+ { UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_DAY_OF_WEEK, kResolveSTOP },
+ { UCAL_WEEK_OF_YEAR, UCAL_DOW_LOCAL, kResolveSTOP },
+ { UCAL_WEEK_OF_MONTH, UCAL_DOW_LOCAL, kResolveSTOP },
+ { UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_DOW_LOCAL, kResolveSTOP },
+ { UCAL_DAY_OF_YEAR, kResolveSTOP },
+ { kResolveRemap | UCAL_DAY_OF_MONTH, UCAL_IS_LEAP_MONTH, kResolveSTOP },
+ { kResolveSTOP }
+ },
+ {
+ { UCAL_WEEK_OF_YEAR, kResolveSTOP },
+ { UCAL_WEEK_OF_MONTH, kResolveSTOP },
+ { UCAL_DAY_OF_WEEK_IN_MONTH, kResolveSTOP },
+ { kResolveRemap | UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_DAY_OF_WEEK, kResolveSTOP },
+ { kResolveRemap | UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_DOW_LOCAL, kResolveSTOP },
+ { kResolveSTOP }
+ },
+ {{kResolveSTOP}}
+};
+
+/**
+ * Override Calendar to add IS_LEAP_MONTH to the field resolution
+ * table.
+ * @stable ICU 2.8
+ */
+const UFieldResolutionTable* ChineseCalendar::getFieldResolutionTable() const {
+ return CHINESE_DATE_PRECEDENCE;
+}
+
+/**
+ * Return the Julian day number of day before the first day of the
+ * given month in the given extended year.
+ *
+ * <p>Note: This method reads the IS_LEAP_MONTH field to determine
+ * whether the given month is a leap month.
+ * @param eyear the extended year
+ * @param month the zero-based month. The month is also determined
+ * by reading the IS_LEAP_MONTH field.
+ * @return the Julian day number of the day before the first
+ * day of the given month and year
+ * @stable ICU 2.8
+ */
+int32_t ChineseCalendar::handleComputeMonthStart(int32_t eyear, int32_t month, UBool useMonth) const {
+
+ ChineseCalendar *nonConstThis = (ChineseCalendar*)this; // cast away const
+
+ // If the month is out of range, adjust it into range, and
+ // modify the extended year value accordingly.
+ if (month < 0 || month > 11) {
+ double m = month;
+ eyear += (int32_t)ClockMath::floorDivide(m, 12.0, m);
+ month = (int32_t)m;
+ }
+
+ int32_t gyear = eyear + CHINESE_EPOCH_YEAR - 1; // Gregorian year
+ int32_t theNewYear = newYear(gyear);
+ int32_t newMoon = newMoonNear(theNewYear + month * 29, TRUE);
+
+ int32_t julianDay = newMoon + kEpochStartAsJulianDay;
+
+ // Save fields for later restoration
+ int32_t saveMonth = internalGet(UCAL_MONTH);
+ int32_t saveIsLeapMonth = internalGet(UCAL_IS_LEAP_MONTH);
+
+ // Ignore IS_LEAP_MONTH field if useMonth is false
+ int32_t isLeapMonth = useMonth ? saveIsLeapMonth : 0;
+
+ UErrorCode status = U_ZERO_ERROR;
+ nonConstThis->computeGregorianFields(julianDay, status);
+ if (U_FAILURE(status))
+ return 0;
+
+ // This will modify the MONTH and IS_LEAP_MONTH fields (only)
+ nonConstThis->computeChineseFields(newMoon, getGregorianYear(),
+ getGregorianMonth(), FALSE);
+
+ if (month != internalGet(UCAL_MONTH) ||
+ isLeapMonth != internalGet(UCAL_IS_LEAP_MONTH)) {
+ newMoon = newMoonNear(newMoon + SYNODIC_GAP, TRUE);
+ julianDay = newMoon + kEpochStartAsJulianDay;
+ }
+
+ nonConstThis->internalSet(UCAL_MONTH, saveMonth);
+ nonConstThis->internalSet(UCAL_IS_LEAP_MONTH, saveIsLeapMonth);
+
+ return julianDay - 1;
+}
+
+
+/**
+ * Override Calendar to handle leap months properly.
+ * @stable ICU 2.8
+ */
+void ChineseCalendar::add(UCalendarDateFields field, int32_t amount, UErrorCode& status) {
+ switch (field) {
+ case UCAL_MONTH:
+ if (amount != 0) {
+ int32_t dom = get(UCAL_DAY_OF_MONTH, status);
+ if (U_FAILURE(status)) break;
+ int32_t day = get(UCAL_JULIAN_DAY, status) - kEpochStartAsJulianDay; // Get local day
+ if (U_FAILURE(status)) break;
+ int32_t moon = day - dom + 1; // New moon
+ offsetMonth(moon, dom, amount);
+ }
+ break;
+ default:
+ Calendar::add(field, amount, status);
+ break;
+ }
+}
+
+/**
+ * Override Calendar to handle leap months properly.
+ * @stable ICU 2.8
+ */
+void ChineseCalendar::add(EDateFields field, int32_t amount, UErrorCode& status) {
+ add((UCalendarDateFields)field, amount, status);
+}
+
+/**
+ * Override Calendar to handle leap months properly.
+ * @stable ICU 2.8
+ */
+void ChineseCalendar::roll(UCalendarDateFields field, int32_t amount, UErrorCode& status) {
+ switch (field) {
+ case UCAL_MONTH:
+ if (amount != 0) {
+ int32_t dom = get(UCAL_DAY_OF_MONTH, status);
+ if (U_FAILURE(status)) break;
+ int32_t day = get(UCAL_JULIAN_DAY, status) - kEpochStartAsJulianDay; // Get local day
+ if (U_FAILURE(status)) break;
+ int32_t moon = day - dom + 1; // New moon (start of this month)
+
+ // Note throughout the following: Months 12 and 1 are never
+ // followed by a leap month (D&R p. 185).
+
+ // Compute the adjusted month number m. This is zero-based
+ // value from 0..11 in a non-leap year, and from 0..12 in a
+ // leap year.
+ int32_t m = get(UCAL_MONTH, status); // 0-based month
+ if (U_FAILURE(status)) break;
+ if (isLeapYear) { // (member variable)
+ if (get(UCAL_IS_LEAP_MONTH, status) == 1) {
+ ++m;
+ } else {
+ // Check for a prior leap month. (In the
+ // following, month 0 is the first month of the
+ // year.) Month 0 is never followed by a leap
+ // month, and we know month m is not a leap month.
+ // moon1 will be the start of month 0 if there is
+ // no leap month between month 0 and month m;
+ // otherwise it will be the start of month 1.
+ int moon1 = moon -
+ (int) (CalendarAstronomer::SYNODIC_MONTH * (m - 0.5));
+ moon1 = newMoonNear(moon1, TRUE);
+ if (isLeapMonthBetween(moon1, moon)) {
+ ++m;
+ }
+ }
+ if (U_FAILURE(status)) break;
+ }
+
+ // Now do the standard roll computation on m, with the
+ // allowed range of 0..n-1, where n is 12 or 13.
+ int32_t n = isLeapYear ? 13 : 12; // Months in this year
+ int32_t newM = (m + amount) % n;
+ if (newM < 0) {
+ newM += n;
+ }
+
+ if (newM != m) {
+ offsetMonth(moon, dom, newM - m);
+ }
+ }
+ break;
+ default:
+ Calendar::roll(field, amount, status);
+ break;
+ }
+}
+
+void ChineseCalendar::roll(EDateFields field, int32_t amount, UErrorCode& status) {
+ roll((UCalendarDateFields)field, amount, status);
+}
+
+
+//------------------------------------------------------------------
+// Support methods and constants
+//------------------------------------------------------------------
+
+/**
+ * Convert local days to UTC epoch milliseconds.
+ * @param days days after January 1, 1970 0:00 Asia/Shanghai
+ * @return milliseconds after January 1, 1970 0:00 GMT
+ */
+double ChineseCalendar::daysToMillis(double days) {
+ return (days * kOneDay) - CHINA_OFFSET;
+}
+
+/**
+ * Convert UTC epoch milliseconds to local days.
+ * @param millis milliseconds after January 1, 1970 0:00 GMT
+ * @return days after January 1, 1970 0:00 Asia/Shanghai
+ */
+double ChineseCalendar::millisToDays(double millis) {
+ return ClockMath::floorDivide(millis + CHINA_OFFSET, kOneDay);
+}
+
+//------------------------------------------------------------------
+// Astronomical computations
+//------------------------------------------------------------------
+
+
+/**
+ * Return the major solar term on or after December 15 of the given
+ * Gregorian year, that is, the winter solstice of the given year.
+ * Computations are relative to Asia/Shanghai time zone.
+ * @param gyear a Gregorian year
+ * @return days after January 1, 1970 0:00 Asia/Shanghai of the
+ * winter solstice of the given year
+ */
+int32_t ChineseCalendar::winterSolstice(int32_t gyear) const {
+
+ UErrorCode status = U_ZERO_ERROR;
+ int32_t cacheValue = CalendarCache::get(&gChineseCalendarWinterSolsticeCache, gyear, status);
+
+ if (cacheValue == 0) {
+ // In books December 15 is used, but it fails for some years
+ // using our algorithms, e.g.: 1298 1391 1492 1553 1560. That
+ // is, winterSolstice(1298) starts search at Dec 14 08:00:00
+ // PST 1298 with a final result of Dec 14 10:31:59 PST 1299.
+ double ms = daysToMillis(Grego::fieldsToDay(gyear, UCAL_DECEMBER, 1));
+
+ umtx_lock(&astroLock);
+ if(gChineseCalendarAstro == NULL) {
+ gChineseCalendarAstro = new CalendarAstronomer();
+ ucln_i18n_registerCleanup(UCLN_I18N_CHINESE_CALENDAR, calendar_chinese_cleanup);
+ }
+ gChineseCalendarAstro->setTime(ms);
+ UDate solarLong = gChineseCalendarAstro->getSunTime(CalendarAstronomer::WINTER_SOLSTICE(), TRUE);
+ umtx_unlock(&astroLock);
+
+ // Winter solstice is 270 degrees solar longitude aka Dongzhi
+ cacheValue = (int32_t)millisToDays(solarLong);
+ CalendarCache::put(&gChineseCalendarWinterSolsticeCache, gyear, cacheValue, status);
+ }
+ if(U_FAILURE(status)) {
+ cacheValue = 0;
+ }
+ return cacheValue;
+}
+
+/**
+ * Return the closest new moon to the given date, searching either
+ * forward or backward in time.
+ * @param days days after January 1, 1970 0:00 Asia/Shanghai
+ * @param after if true, search for a new moon on or after the given
+ * date; otherwise, search for a new moon before it
+ * @return days after January 1, 1970 0:00 Asia/Shanghai of the nearest
+ * new moon after or before <code>days</code>
+ */
+int32_t ChineseCalendar::newMoonNear(double days, UBool after) const {
+
+ umtx_lock(&astroLock);
+ if(gChineseCalendarAstro == NULL) {
+ gChineseCalendarAstro = new CalendarAstronomer();
+ ucln_i18n_registerCleanup(UCLN_I18N_CHINESE_CALENDAR, calendar_chinese_cleanup);
+ }
+ gChineseCalendarAstro->setTime(daysToMillis(days));
+ UDate newMoon = gChineseCalendarAstro->getMoonTime(CalendarAstronomer::NEW_MOON(), after);
+ umtx_unlock(&astroLock);
+
+ return (int32_t) millisToDays(newMoon);
+}
+
+/**
+ * Return the nearest integer number of synodic months between
+ * two dates.
+ * @param day1 days after January 1, 1970 0:00 Asia/Shanghai
+ * @param day2 days after January 1, 1970 0:00 Asia/Shanghai
+ * @return the nearest integer number of months between day1 and day2
+ */
+int32_t ChineseCalendar::synodicMonthsBetween(int32_t day1, int32_t day2) const {
+ double roundme = ((day2 - day1) / CalendarAstronomer::SYNODIC_MONTH);
+ return (int32_t) (roundme + (roundme >= 0 ? .5 : -.5));
+}
+
+/**
+ * Return the major solar term on or before a given date. This
+ * will be an integer from 1..12, with 1 corresponding to 330 degrees,
+ * 2 to 0 degrees, 3 to 30 degrees,..., and 12 to 300 degrees.
+ * @param days days after January 1, 1970 0:00 Asia/Shanghai
+ */
+int32_t ChineseCalendar::majorSolarTerm(int32_t days) const {
+
+ umtx_lock(&astroLock);
+ if(gChineseCalendarAstro == NULL) {
+ gChineseCalendarAstro = new CalendarAstronomer();
+ ucln_i18n_registerCleanup(UCLN_I18N_CHINESE_CALENDAR, calendar_chinese_cleanup);
+ }
+ gChineseCalendarAstro->setTime(daysToMillis(days));
+ UDate solarLongitude = gChineseCalendarAstro->getSunLongitude();
+ umtx_unlock(&astroLock);
+
+ // Compute (floor(solarLongitude / (pi/6)) + 2) % 12
+ int32_t term = ( ((int32_t)(6 * solarLongitude / CalendarAstronomer::PI)) + 2 ) % 12;
+ if (term < 1) {
+ term += 12;
+ }
+ return term;
+}
+
+/**
+ * Return true if the given month lacks a major solar term.
+ * @param newMoon days after January 1, 1970 0:00 Asia/Shanghai of a new
+ * moon
+ */
+UBool ChineseCalendar::hasNoMajorSolarTerm(int32_t newMoon) const {
+ return majorSolarTerm(newMoon) ==
+ majorSolarTerm(newMoonNear(newMoon + SYNODIC_GAP, TRUE));
+}
+
+
+//------------------------------------------------------------------
+// Time to fields
+//------------------------------------------------------------------
+
+/**
+ * Return true if there is a leap month on or after month newMoon1 and
+ * at or before month newMoon2.
+ * @param newMoon1 days after January 1, 1970 0:00 Asia/Shanghai of a
+ * new moon
+ * @param newMoon2 days after January 1, 1970 0:00 Asia/Shanghai of a
+ * new moon
+ */
+UBool ChineseCalendar::isLeapMonthBetween(int32_t newMoon1, int32_t newMoon2) const {
+
+#ifdef U_DEBUG_CHNSECAL
+ // This is only needed to debug the timeOfAngle divergence bug.
+ // Remove this later. Liu 11/9/00
+ if (synodicMonthsBetween(newMoon1, newMoon2) >= 50) {
+ U_DEBUG_CHNSECAL_MSG((
+ "isLeapMonthBetween(%d, %d): Invalid parameters", newMoon1, newMoon2
+ ));
+ }
+#endif
+
+ return (newMoon2 >= newMoon1) &&
+ (isLeapMonthBetween(newMoon1, newMoonNear(newMoon2 - SYNODIC_GAP, FALSE)) ||
+ hasNoMajorSolarTerm(newMoon2));
+}
+
+/**
+ * Compute fields for the Chinese calendar system. This method can
+ * either set all relevant fields, as required by
+ * <code>handleComputeFields()</code>, or it can just set the MONTH and
+ * IS_LEAP_MONTH fields, as required by
+ * <code>handleComputeMonthStart()</code>.
+ *
+ * <p>As a side effect, this method sets {@link #isLeapYear}.
+ * @param days days after January 1, 1970 0:00 Asia/Shanghai of the
+ * date to compute fields for
+ * @param gyear the Gregorian year of the given date
+ * @param gmonth the Gregorian month of the given date
+ * @param setAllFields if true, set the EXTENDED_YEAR, ERA, YEAR,
+ * DAY_OF_MONTH, and DAY_OF_YEAR fields. In either case set the MONTH
+ * and IS_LEAP_MONTH fields.
+ */
+void ChineseCalendar::computeChineseFields(int32_t days, int32_t gyear, int32_t gmonth,
+ UBool setAllFields) {
+
+ // Find the winter solstices before and after the target date.
+ // These define the boundaries of this Chinese year, specifically,
+ // the position of month 11, which always contains the solstice.
+ // We want solsticeBefore <= date < solsticeAfter.
+ int32_t solsticeBefore;
+ int32_t solsticeAfter = winterSolstice(gyear);
+ if (days < solsticeAfter) {
+ solsticeBefore = winterSolstice(gyear - 1);
+ } else {
+ solsticeBefore = solsticeAfter;
+ solsticeAfter = winterSolstice(gyear + 1);
+ }
+
+ // Find the start of the month after month 11. This will be either
+ // the prior month 12 or leap month 11 (very rare). Also find the
+ // start of the following month 11.
+ int32_t firstMoon = newMoonNear(solsticeBefore + 1, TRUE);
+ int32_t lastMoon = newMoonNear(solsticeAfter + 1, FALSE);
+ int32_t thisMoon = newMoonNear(days + 1, FALSE); // Start of this month
+ // Note: isLeapYear is a member variable
+ isLeapYear = synodicMonthsBetween(firstMoon, lastMoon) == 12;
+
+ int32_t month = synodicMonthsBetween(firstMoon, thisMoon);
+ if (isLeapYear && isLeapMonthBetween(firstMoon, thisMoon)) {
+ month--;
+ }
+ if (month < 1) {
+ month += 12;
+ }
+
+ UBool isLeapMonth = isLeapYear &&
+ hasNoMajorSolarTerm(thisMoon) &&
+ !isLeapMonthBetween(firstMoon, newMoonNear(thisMoon - SYNODIC_GAP, FALSE));
+
+ internalSet(UCAL_MONTH, month-1); // Convert from 1-based to 0-based
+ internalSet(UCAL_IS_LEAP_MONTH, isLeapMonth?1:0);
+
+ if (setAllFields) {
+
+ int32_t year = gyear - CHINESE_EPOCH_YEAR;
+ if (month < 11 ||
+ gmonth >= UCAL_JULY) {
+ year++;
+ }
+ int32_t dayOfMonth = days - thisMoon + 1;
+
+ internalSet(UCAL_EXTENDED_YEAR, year);
+
+ // 0->0,60 1->1,1 60->1,60 61->2,1 etc.
+ int32_t yearOfCycle;
+ int32_t cycle = ClockMath::floorDivide(year - 1, 60, yearOfCycle);
+ internalSet(UCAL_ERA, cycle + 1);
+ internalSet(UCAL_YEAR, yearOfCycle + 1);
+
+ internalSet(UCAL_DAY_OF_MONTH, dayOfMonth);
+
+ // Days will be before the first new year we compute if this
+ // date is in month 11, leap 11, 12. There is never a leap 12.
+ // New year computations are cached so this should be cheap in
+ // the long run.
+ int32_t theNewYear = newYear(gyear);
+ if (days < theNewYear) {
+ theNewYear = newYear(gyear-1);
+ }
+ internalSet(UCAL_DAY_OF_YEAR, days - theNewYear + 1);
+ }
+}
+
+
+//------------------------------------------------------------------
+// Fields to time
+//------------------------------------------------------------------
+
+/**
+ * Return the Chinese new year of the given Gregorian year.
+ * @param gyear a Gregorian year
+ * @return days after January 1, 1970 0:00 Asia/Shanghai of the
+ * Chinese new year of the given year (this will be a new moon)
+ */
+int32_t ChineseCalendar::newYear(int32_t gyear) const {
+ UErrorCode status = U_ZERO_ERROR;
+ int32_t cacheValue = CalendarCache::get(&gChineseCalendarNewYearCache, gyear, status);
+
+ if (cacheValue == 0) {
+
+ int32_t solsticeBefore= winterSolstice(gyear - 1);
+ int32_t solsticeAfter = winterSolstice(gyear);
+ int32_t newMoon1 = newMoonNear(solsticeBefore + 1, TRUE);
+ int32_t newMoon2 = newMoonNear(newMoon1 + SYNODIC_GAP, TRUE);
+ int32_t newMoon11 = newMoonNear(solsticeAfter + 1, FALSE);
+
+ if (synodicMonthsBetween(newMoon1, newMoon11) == 12 &&
+ (hasNoMajorSolarTerm(newMoon1) || hasNoMajorSolarTerm(newMoon2))) {
+ cacheValue = newMoonNear(newMoon2 + SYNODIC_GAP, TRUE);
+ } else {
+ cacheValue = newMoon2;
+ }
+
+ CalendarCache::put(&gChineseCalendarNewYearCache, gyear, cacheValue, status);
+ }
+ if(U_FAILURE(status)) {
+ cacheValue = 0;
+ }
+ return cacheValue;
+}
+
+/**
+ * Adjust this calendar to be delta months before or after a given
+ * start position, pinning the day of month if necessary. The start
+ * position is given as a local days number for the start of the month
+ * and a day-of-month. Used by add() and roll().
+ * @param newMoon the local days of the first day of the month of the
+ * start position (days after January 1, 1970 0:00 Asia/Shanghai)
+ * @param dom the 1-based day-of-month of the start position
+ * @param delta the number of months to move forward or backward from
+ * the start position
+ */
+void ChineseCalendar::offsetMonth(int32_t newMoon, int32_t dom, int32_t delta) {
+ UErrorCode status = U_ZERO_ERROR;
+
+ // Move to the middle of the month before our target month.
+ newMoon += (int32_t) (CalendarAstronomer::SYNODIC_MONTH * (delta - 0.5));
+
+ // Search forward to the target month's new moon
+ newMoon = newMoonNear(newMoon, TRUE);
+
+ // Find the target dom
+ int32_t jd = newMoon + kEpochStartAsJulianDay - 1 + dom;
+
+ // Pin the dom. In this calendar all months are 29 or 30 days
+ // so pinning just means handling dom 30.
+ if (dom > 29) {
+ set(UCAL_JULIAN_DAY, jd-1);
+ // TODO Fix this. We really shouldn't ever have to
+ // explicitly call complete(). This is either a bug in
+ // this method, in ChineseCalendar, or in
+ // Calendar.getActualMaximum(). I suspect the last.
+ complete(status);
+ if (U_FAILURE(status)) return;
+ if (getActualMaximum(UCAL_DAY_OF_MONTH, status) >= dom) {
+ if (U_FAILURE(status)) return;
+ set(UCAL_JULIAN_DAY, jd);
+ }
+ } else {
+ set(UCAL_JULIAN_DAY, jd);
+ }
+}
+
+
+UBool
+ChineseCalendar::inDaylightTime(UErrorCode& status) const
+{
+ // copied from GregorianCalendar
+ if (U_FAILURE(status) || !getTimeZone().useDaylightTime())
+ return FALSE;
+
+ // Force an update of the state of the Calendar.
+ ((ChineseCalendar*)this)->complete(status); // cast away const
+
+ return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE);
+}
+
+// default century
+const UDate ChineseCalendar::fgSystemDefaultCentury = DBL_MIN;
+const int32_t ChineseCalendar::fgSystemDefaultCenturyYear = -1;
+
+UDate ChineseCalendar::fgSystemDefaultCenturyStart = DBL_MIN;
+int32_t ChineseCalendar::fgSystemDefaultCenturyStartYear = -1;
+
+
+UBool ChineseCalendar::haveDefaultCentury() const
+{
+ return TRUE;
+}
+
+UDate ChineseCalendar::defaultCenturyStart() const
+{
+ return internalGetDefaultCenturyStart();
+}
+
+int32_t ChineseCalendar::defaultCenturyStartYear() const
+{
+ return internalGetDefaultCenturyStartYear();
+}
+
+UDate
+ChineseCalendar::internalGetDefaultCenturyStart() const
+{
+ // lazy-evaluate systemDefaultCenturyStart
+ UBool needsUpdate;
+ UMTX_CHECK(NULL, (fgSystemDefaultCenturyStart == fgSystemDefaultCentury), needsUpdate);
+
+ if (needsUpdate) {
+ initializeSystemDefaultCentury();
+ }
+
+ // use defaultCenturyStart unless it's the flag value;
+ // then use systemDefaultCenturyStart
+
+ return fgSystemDefaultCenturyStart;
+}
+
+int32_t
+ChineseCalendar::internalGetDefaultCenturyStartYear() const
+{
+ // lazy-evaluate systemDefaultCenturyStartYear
+ UBool needsUpdate;
+ UMTX_CHECK(NULL, (fgSystemDefaultCenturyStart == fgSystemDefaultCentury), needsUpdate);
+
+ if (needsUpdate) {
+ initializeSystemDefaultCentury();
+ }
+
+ // use defaultCenturyStart unless it's the flag value;
+ // then use systemDefaultCenturyStartYear
+
+ return fgSystemDefaultCenturyStartYear;
+}
+
+void
+ChineseCalendar::initializeSystemDefaultCentury()
+{
+ // initialize systemDefaultCentury and systemDefaultCenturyYear based
+ // on the current time. They'll be set to 80 years before
+ // the current time.
+ UErrorCode status = U_ZERO_ERROR;
+ ChineseCalendar calendar(Locale("@calendar=chinese"),status);
+ if (U_SUCCESS(status))
+ {
+ calendar.setTime(Calendar::getNow(), status);
+ calendar.add(UCAL_YEAR, -80, status);
+ UDate newStart = calendar.getTime(status);
+ int32_t newYear = calendar.get(UCAL_YEAR, status);
+ umtx_lock(NULL);
+ if (fgSystemDefaultCenturyStart == fgSystemDefaultCentury)
+ {
+ fgSystemDefaultCenturyStartYear = newYear;
+ fgSystemDefaultCenturyStart = newStart;
+ }
+ umtx_unlock(NULL);
+ }
+ // We have no recourse upon failure unless we want to propagate the failure
+ // out.
+}
+
+UOBJECT_DEFINE_RTTI_IMPLEMENTATION(ChineseCalendar)
+
+U_NAMESPACE_END
+
+#endif
projects / apple / icu.git / blobdiff