icuSources/i18n/persncal.cpp

   1 // © 2016 and later: Unicode, Inc. and others.
   2 // License & terms of use: http://www.unicode.org/copyright.html
   3 /*
   4  ******************************************************************************
   5  * Copyright (C) 2003-2013, International Business Machines Corporation
   6  * and others. All Rights Reserved.
   7  ******************************************************************************
   8  *
   9  * File PERSNCAL.CPP
  10  *
  11  * Modification History:
  12  *
  13  *   Date        Name        Description
  14  *   9/23/2003   mehran      posted to icu-design
  15  *   10/1/2012   roozbeh     Fixed algorithm and heavily refactored and rewrote
  16  *                           based on the implementation of Gregorian
  17  *****************************************************************************
  18  */
  19
  20 #include "persncal.h"
  21
  22 #if !UCONFIG_NO_FORMATTING
  23
  24 #include "umutex.h"
  25 #include "gregoimp.h" // Math
  26 #include <float.h>
  27
  28 static const int16_t kPersianNumDays[]
  29 = {0,31,62,93,124,155,186,216,246,276,306,336}; // 0-based, for day-in-year
  30 static const int8_t kPersianMonthLength[]
  31 = {31,31,31,31,31,31,30,30,30,30,30,29}; // 0-based
  32 static const int8_t kPersianLeapMonthLength[]
  33 = {31,31,31,31,31,31,30,30,30,30,30,30}; // 0-based
  34
  35 static const int32_t kPersianCalendarLimits[UCAL_FIELD_COUNT][4] = {
  36     // Minimum  Greatest     Least   Maximum
  37     //           Minimum   Maximum
  38     {        0,        0,        0,        0}, // ERA
  39     { -5000000, -5000000,  5000000,  5000000}, // YEAR
  40     {        0,        0,       11,       11}, // MONTH
  41     {        1,        1,       52,       53}, // WEEK_OF_YEAR
  42     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // WEEK_OF_MONTH
  43     {        1,       1,        29,       31}, // DAY_OF_MONTH
  44     {        1,       1,       365,      366}, // DAY_OF_YEAR
  45     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DAY_OF_WEEK
  46     {        1,       1,         5,        5}, // DAY_OF_WEEK_IN_MONTH
  47     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // AM_PM
  48     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR
  49     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR_OF_DAY
  50     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MINUTE
  51     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // SECOND
  52     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECOND
  53     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // ZONE_OFFSET
  54     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DST_OFFSET
  55     { -5000000, -5000000,  5000000,  5000000}, // YEAR_WOY
  56     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DOW_LOCAL
  57     { -5000000, -5000000,  5000000,  5000000}, // EXTENDED_YEAR
  58     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // JULIAN_DAY
  59     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECONDS_IN_DAY
  60     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // IS_LEAP_MONTH
  61 };
  62
  63 U_NAMESPACE_BEGIN
  64
  65 static const int32_t PERSIAN_EPOCH = 1948320;
  66
  67 // Implementation of the PersianCalendar class
  68
  69 //-------------------------------------------------------------------------
  70 // Constructors...
  71 //-------------------------------------------------------------------------
  72
  73 const char *PersianCalendar::getType() const {
  74     return "persian";
  75 }
  76
  77 Calendar* PersianCalendar::clone() const {
  78     return new PersianCalendar(*this);
  79 }
  80
  81 PersianCalendar::PersianCalendar(const Locale& aLocale, UErrorCode& success)
  82   :   Calendar(TimeZone::createDefault(), aLocale, success)
  83 {
  84     setTimeInMillis(getNow(), success); // Call this again now that the vtable is set up properly.
  85 }
  86
  87 PersianCalendar::PersianCalendar(const PersianCalendar& other) : Calendar(other) {
  88 }
  89
  90 PersianCalendar::~PersianCalendar()
  91 {
  92 }
  93
  94 //-------------------------------------------------------------------------
  95 // Minimum / Maximum access functions
  96 //-------------------------------------------------------------------------
  97
  98
  99 int32_t PersianCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const {
 100     return kPersianCalendarLimits[field][limitType];
 101 }
 102
 103 //-------------------------------------------------------------------------
 104 // Assorted calculation utilities
 105 //
 106
 107 /**
 108  * Determine whether a year is a leap year in the Persian calendar
 109  */
 110 UBool PersianCalendar::isLeapYear(int32_t year)
 111 {
 112     int32_t remainder;
 113     ClockMath::floorDivide(25 * year + 11, 33, remainder);
 114     return (remainder < 8);
 115 }
 116
 117 /**
 118  * Return the day # on which the given year starts.  Days are counted
 119  * from the Persian epoch, origin 0.
 120  */
 121 int32_t PersianCalendar::yearStart(int32_t year) {
 122     return handleComputeMonthStart(year,0,FALSE);
 123 }
 124
 125 /**
 126  * Return the day # on which the given month starts.  Days are counted
 127  * from the Persian epoch, origin 0.
 128  *
 129  * @param year  The Persian year
 130  * @param year  The Persian month, 0-based
 131  */
 132 int32_t PersianCalendar::monthStart(int32_t year, int32_t month) const {
 133     return handleComputeMonthStart(year,month,TRUE);
 134 }
 135
 136 //----------------------------------------------------------------------
 137 // Calendar framework
 138 //----------------------------------------------------------------------
 139
 140 /**
 141  * Return the length (in days) of the given month.
 142  *
 143  * @param year  The Persian year
 144  * @param year  The Persian month, 0-based
 145  */
 146 int32_t PersianCalendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const {
 147     // If the month is out of range, adjust it into range, and
 148     // modify the extended year value accordingly.
 149     if (month < 0 || month > 11) {
 150         extendedYear += ClockMath::floorDivide(month, 12, month);
 151     }
 152
 153     return isLeapYear(extendedYear) ? kPersianLeapMonthLength[month] : kPersianMonthLength[month];
 154 }
 155
 156 /**
 157  * Return the number of days in the given Persian year
 158  */
 159 int32_t PersianCalendar::handleGetYearLength(int32_t extendedYear) const {
 160     return isLeapYear(extendedYear) ? 366 : 365;
 161 }
 162
 163 //-------------------------------------------------------------------------
 164 // Functions for converting from field values to milliseconds....
 165 //-------------------------------------------------------------------------
 166
 167 // Return JD of start of given month/year
 168 int32_t PersianCalendar::handleComputeMonthStart(int32_t eyear, int32_t month, UBool /*useMonth*/) const {
 169     // If the month is out of range, adjust it into range, and
 170     // modify the extended year value accordingly.
 171     if (month < 0 || month > 11) {
 172         eyear += ClockMath::floorDivide(month, 12, month);
 173     }
 174
 175     int32_t julianDay = PERSIAN_EPOCH - 1 + 365 * (eyear - 1) + ClockMath::floorDivide(8 * eyear + 21, 33);
 176
 177     if (month != 0) {
 178         julianDay += kPersianNumDays[month];
 179     }
 180
 181     return julianDay;
 182 }
 183
 184 //-------------------------------------------------------------------------
 185 // Functions for converting from milliseconds to field values
 186 //-------------------------------------------------------------------------
 187
 188 int32_t PersianCalendar::handleGetExtendedYear() {
 189     int32_t year;
 190     if (newerField(UCAL_EXTENDED_YEAR, UCAL_YEAR) == UCAL_EXTENDED_YEAR) {
 191         year = internalGet(UCAL_EXTENDED_YEAR, 1); // Default to year 1
 192     } else {
 193         year = internalGet(UCAL_YEAR, 1); // Default to year 1
 194     }
 195     return year;
 196 }
 197
 198 /**
 199  * Override Calendar to compute several fields specific to the Persian
 200  * calendar system.  These are:
 201  *
 202  * <ul><li>ERA
 203  * <li>YEAR
 204  * <li>MONTH
 205  * <li>DAY_OF_MONTH
 206  * <li>DAY_OF_YEAR
 207  * <li>EXTENDED_YEAR</ul>
 208  *
 209  * The DAY_OF_WEEK and DOW_LOCAL fields are already set when this
 210  * method is called.
 211  */
 212 void PersianCalendar::handleComputeFields(int32_t julianDay, UErrorCode &/*status*/) {
 213     int32_t year, month, dayOfMonth, dayOfYear;
 214
 215     int32_t daysSinceEpoch = julianDay - PERSIAN_EPOCH;
 216     year = 1 + (int32_t)ClockMath::floorDivide(33 * (int64_t)daysSinceEpoch + 3, (int64_t)12053);
 217
 218     int32_t farvardin1 = 365 * (year - 1) + ClockMath::floorDivide(8 * year + 21, 33);
 219     dayOfYear = (daysSinceEpoch - farvardin1); // 0-based
 220     if (dayOfYear < 216) { // Compute 0-based month
 221         month = dayOfYear / 31;
 222     } else {
 223         month = (dayOfYear - 6) / 30;
 224     }
 225     dayOfMonth = dayOfYear - kPersianNumDays[month] + 1;
 226     ++dayOfYear; // Make it 1-based now
 227
 228     internalSet(UCAL_ERA, 0);
 229     internalSet(UCAL_YEAR, year);
 230     internalSet(UCAL_EXTENDED_YEAR, year);
 231     internalSet(UCAL_MONTH, month);
 232     internalSet(UCAL_DAY_OF_MONTH, dayOfMonth);
 233     internalSet(UCAL_DAY_OF_YEAR, dayOfYear);
 234 }
 235
 236 UBool
 237 PersianCalendar::inDaylightTime(UErrorCode& status) const
 238 {
 239     // copied from GregorianCalendar
 240     if (U_FAILURE(status) || !getTimeZone().useDaylightTime())
 241         return FALSE;
 242
 243     // Force an update of the state of the Calendar.
 244     ((PersianCalendar*)this)->complete(status); // cast away const
 245
 246     return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE);
 247 }
 248
 249 // default century
 250
 251 static UDate           gSystemDefaultCenturyStart       = DBL_MIN;
 252 static int32_t         gSystemDefaultCenturyStartYear   = -1;
 253 static icu::UInitOnce  gSystemDefaultCenturyInit        = U_INITONCE_INITIALIZER;
 254
 255 UBool PersianCalendar::haveDefaultCentury() const
 256 {
 257     return TRUE;
 258 }
 259
 260 static void U_CALLCONV initializeSystemDefaultCentury() {
 261     // initialize systemDefaultCentury and systemDefaultCenturyYear based
 262     // on the current time.  They'll be set to 80 years before
 263     // the current time.
 264     UErrorCode status = U_ZERO_ERROR;
 265     PersianCalendar calendar(Locale("@calendar=persian"),status);
 266     if (U_SUCCESS(status))
 267     {
 268         calendar.setTime(Calendar::getNow(), status);
 269         calendar.add(UCAL_YEAR, -80, status);
 270
 271         gSystemDefaultCenturyStart = calendar.getTime(status);
 272         gSystemDefaultCenturyStartYear = calendar.get(UCAL_YEAR, status);
 273     }
 274     // We have no recourse upon failure unless we want to propagate the failure
 275     // out.
 276 }
 277
 278 UDate PersianCalendar::defaultCenturyStart() const {
 279     // lazy-evaluate systemDefaultCenturyStart
 280     umtx_initOnce(gSystemDefaultCenturyInit, &initializeSystemDefaultCentury);
 281     return gSystemDefaultCenturyStart;
 282 }
 283
 284 int32_t PersianCalendar::defaultCenturyStartYear() const {
 285     // lazy-evaluate systemDefaultCenturyStartYear
 286     umtx_initOnce(gSystemDefaultCenturyInit, &initializeSystemDefaultCentury);
 287     return gSystemDefaultCenturyStartYear;
 288 }
 289
 290 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(PersianCalendar)
 291
 292 U_NAMESPACE_END
 293
 294 #endif
 295