icuSources/i18n/persncal.cpp

   1 /*
   2  ******************************************************************************
   3  * Copyright (C) 2003-2008, International Business Machines Corporation
   4  * and others. All Rights Reserved.
   5  ******************************************************************************
   6  *
   7  * File PERSNCAL.CPP
   8  *
   9  * Modification History:
  10  *
  11  *   Date        Name        Description
  12  *   9/23/2003 mehran        posted to icu-design
  13  *****************************************************************************
  14  */
  15
  16 #include "persncal.h"
  17
  18 #if !UCONFIG_NO_FORMATTING
  19
  20 #include "umutex.h"
  21 #include <float.h>
  22
  23 static const int8_t monthDays[] = { 31, 31, 31, 31, 31, 31, 30, 30, 30, 30, 30, 29 };
  24
  25 static int32_t
  26 jalali_to_julian(int year, int month, int day)
  27 {
  28     int32_t daysNo=0;
  29     int i;
  30
  31     year = year -475+2820;
  32     month -= 1;
  33
  34     daysNo=(year/2820)*1029983;
  35     year=year % 2820;
  36
  37     daysNo+=(year/128)* 46751;
  38     if((year/128)>21)
  39     {
  40         daysNo-=46751;
  41         year=(year%128)+128;
  42     }
  43     else
  44         year=year%128;
  45
  46     if(year>=29)
  47     {
  48         year-=29;
  49         daysNo+=10592;
  50     }
  51
  52     if(year>=66)
  53     {
  54         year-=66;
  55         daysNo+=24106;
  56     }
  57     else if( year>=33)
  58     {
  59         daysNo+=(year/33)* 12053;
  60         year=year%33;
  61     }
  62
  63     if (year >= 5)
  64     {
  65         daysNo += 1826;
  66         year -=5;
  67     }
  68     else if (year == 4)
  69     {
  70         daysNo += 1460;
  71         year -=4;
  72     }
  73
  74     daysNo += 1461 * (year/4);
  75     year %= 4;
  76     daysNo += 365 * year;
  77
  78     for (i = 0; i < month; i++) {
  79         daysNo += monthDays[i];
  80     }
  81
  82     daysNo += day;
  83
  84     return daysNo-856493;
  85 }
  86
  87 static void julian_to_jalali (int32_t daysNo, int *h_y, int *h_m, int *h_d)
  88 {
  89     int year=0, month=0, day=0,scalarDays=0;
  90     int i;
  91
  92     daysNo+=856493;
  93     scalarDays=daysNo;
  94     year=(daysNo/1029983)*2820;
  95     daysNo=daysNo%1029983;
  96
  97     if((daysNo/46751)<=21)
  98     {
  99         year+=(daysNo/46751)* 128;
 100         daysNo=daysNo%46751;
 101     }
 102     else
 103     {
 104         year+=(daysNo/46751)* 128;
 105         daysNo=daysNo%46751;
 106         year-=128;
 107         daysNo+=46751;
 108     }
 109
 110     if (daysNo >= 10592)
 111     {
 112         year+= 29;
 113         daysNo -= 10592;
 114     }
 115
 116     if(daysNo>=24106)
 117     {
 118         daysNo-=24106;
 119         year+=66;
 120     }
 121
 122     if(daysNo>=12053)
 123     {
 124         daysNo-=12053;
 125         year+=33;
 126     }
 127
 128
 129     if (daysNo >= 1826)
 130     {
 131         year+= 5;
 132         daysNo -= 1826;
 133     }
 134     else if (daysNo > 1095)
 135     {
 136         year+= 3;
 137         daysNo -= 1095;
 138
 139     }
 140
 141     year +=(4 * (daysNo/1461));
 142     daysNo %= 1461;
 143
 144     if (daysNo == 0)
 145     {
 146         year -= 1;
 147         daysNo = 366;
 148     }
 149     else
 150     {
 151         year += daysNo/365;
 152         daysNo = daysNo % 365;
 153         if (daysNo == 0)
 154         {
 155             year -= 1;
 156             daysNo = 365;
 157         }
 158
 159     }
 160
 161     for (i = 0; i < 11 && daysNo > monthDays[i]; ++i) {
 162         daysNo -= monthDays[i];
 163     }
 164
 165     month = i + 1;
 166
 167     day = daysNo;
 168
 169     *h_d = day;
 170     *h_m = month;
 171     *h_y = year-2345;
 172 }
 173
 174 U_NAMESPACE_BEGIN
 175
 176 // Implementation of the PersianCalendar class
 177
 178 //-------------------------------------------------------------------------
 179 // Constructors...
 180 //-------------------------------------------------------------------------
 181
 182 const char *PersianCalendar::getType() const {
 183     return "persian";
 184 }
 185
 186 Calendar* PersianCalendar::clone() const {
 187     return new PersianCalendar(*this);
 188 }
 189
 190 PersianCalendar::PersianCalendar(const Locale& aLocale, UErrorCode& success)
 191   :   Calendar(TimeZone::createDefault(), aLocale, success)
 192 {
 193     setTimeInMillis(getNow(), success); // Call this again now that the vtable is set up properly.
 194 }
 195
 196 PersianCalendar::PersianCalendar(const PersianCalendar& other) : Calendar(other) {
 197 }
 198
 199 PersianCalendar::~PersianCalendar()
 200 {
 201 }
 202
 203 //-------------------------------------------------------------------------
 204 // Minimum / Maximum access functions
 205 //-------------------------------------------------------------------------
 206
 207 static const int32_t LIMITS[UCAL_FIELD_COUNT][4] = {
 208     // Minimum  Greatest     Least   Maximum
 209     //           Minimum   Maximum
 210     {        0,        0,        0,        0}, // ERA
 211     { -5000000, -5000000,  5000000,  5000000}, // YEAR
 212     {        0,        0,       11,       11}, // MONTH
 213     {        1,        1,       52,       53}, // WEEK_OF_YEAR
 214     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // WEEK_OF_MONTH
 215     {        1,       1,        29,       31}, // DAY_OF_MONTH
 216     {        1,       1,       365,      366}, // DAY_OF_YEAR
 217     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DAY_OF_WEEK
 218     {        1,       1,         5,        5}, // DAY_OF_WEEK_IN_MONTH
 219     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // AM_PM
 220     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR
 221     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR_OF_DAY
 222     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MINUTE
 223     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // SECOND
 224     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECOND
 225     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // ZONE_OFFSET
 226     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DST_OFFSET
 227     { -5000000, -5000000,  5000000,  5000000}, // YEAR_WOY
 228     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DOW_LOCAL
 229     { -5000000, -5000000,  5000000,  5000000}, // EXTENDED_YEAR
 230     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // JULIAN_DAY
 231     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECONDS_IN_DAY
 232     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // IS_LEAP_MONTH
 233 };
 234 static const int32_t MONTH_COUNT[12][4]  = {
 235     //len len2   st  st2
 236     {  31,  31,   0,   0 }, // Farvardin
 237     {  31,  31,  31,  31 }, // Ordibehesht
 238     {  31,  31,  62,  62 }, // Khordad
 239     {  31,  31,  93,  93 }, // Tir
 240     {  31,  31, 124, 124 }, // Mordad
 241     {  31,  31, 155, 155 }, // Shahrivar
 242     {  30,  30, 186, 186 }, // Mehr
 243     {  30,  30, 216, 216 }, // Aban
 244     {  30,  30, 246, 246 }, // Azar
 245     {  30,  30, 276, 276 }, // Dey
 246     {  30,  30, 306, 306 }, // Bahman
 247     {  29,  30, 336, 336 }  // Esfand
 248     // len  length of month
 249     // len2 length of month in a leap year
 250     // st   days in year before start of month
 251     // st2  days in year before month in leap year
 252 };
 253
 254 int32_t PersianCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const {
 255     return LIMITS[field][limitType];
 256 }
 257
 258 //-------------------------------------------------------------------------
 259 // Assorted calculation utilities
 260 //
 261
 262 /**
 263  * Determine whether a year is a leap year in the Persian calendar
 264  */
 265 UBool PersianCalendar::isLeapYear(int32_t year)
 266 {
 267     return jalali_to_julian(year+1,1,1)-jalali_to_julian(year,1,1) == 366;
 268 }
 269
 270 /**
 271  * Return the day # on which the given year starts.  Days are counted
 272  * from the Hijri epoch, origin 0.
 273  */
 274 int32_t PersianCalendar::yearStart(int32_t year) {
 275     return handleComputeMonthStart(year,1,FALSE);
 276 }
 277
 278 /**
 279  * Return the day # on which the given month starts.  Days are counted
 280  * from the Hijri epoch, origin 0.
 281  *
 282  * @param year  The hijri shamsi year
 283  * @param year  The hijri shamsi month, 0-based
 284  */
 285 int32_t PersianCalendar::monthStart(int32_t year, int32_t month) const {
 286     return handleComputeMonthStart(year,month,FALSE);
 287 }
 288
 289 //----------------------------------------------------------------------
 290 // Calendar framework
 291 //----------------------------------------------------------------------
 292
 293 /**
 294  * Return the length (in days) of the given month.
 295  *
 296  * @param year  The hijri shamsi year
 297  * @param year  The hijri shamsi month, 0-based
 298  */
 299 int32_t PersianCalendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const {
 300     return MONTH_COUNT[month][PersianCalendar::isLeapYear(extendedYear)?1:0];
 301 }
 302
 303 /**
 304  * Return the number of days in the given Persian year
 305  */
 306 int32_t PersianCalendar::handleGetYearLength(int32_t extendedYear) const {
 307     return 365 + (PersianCalendar::isLeapYear(extendedYear) ? 1 : 0);
 308 }
 309
 310 //-------------------------------------------------------------------------
 311 // Functions for converting from field values to milliseconds....
 312 //-------------------------------------------------------------------------
 313
 314 // Return JD of start of given month/year
 315 int32_t PersianCalendar::handleComputeMonthStart(int32_t eyear, int32_t month, UBool useMonth) const {
 316     // If the month is out of range, adjust it into range, and
 317     // modify the extended year value accordingly.
 318     if (month < 0 || month > 11) {
 319         eyear += month / 12;
 320         month = month % 12;
 321     }
 322     return jalali_to_julian(eyear,(useMonth?month+1:1),1)-1+1947955;
 323 }
 324
 325 //-------------------------------------------------------------------------
 326 // Functions for converting from milliseconds to field values
 327 //-------------------------------------------------------------------------
 328
 329 int32_t PersianCalendar::handleGetExtendedYear() {
 330     int32_t year;
 331     if (newerField(UCAL_EXTENDED_YEAR, UCAL_YEAR) == UCAL_EXTENDED_YEAR) {
 332         year = internalGet(UCAL_EXTENDED_YEAR, 1); // Default to year 1
 333     } else {
 334         year = internalGet(UCAL_YEAR, 1); // Default to year 1
 335     }
 336     return year;
 337 }
 338
 339 /**
 340  * Override Calendar to compute several fields specific to the Persian
 341  * calendar system.  These are:
 342  *
 343  * <ul><li>ERA
 344  * <li>YEAR
 345  * <li>MONTH
 346  * <li>DAY_OF_MONTH
 347  * <li>DAY_OF_YEAR
 348  * <li>EXTENDED_YEAR</ul>
 349  *
 350  * The DAY_OF_WEEK and DOW_LOCAL fields are already set when this
 351  * method is called. The getGregorianXxx() methods return Gregorian
 352  * calendar equivalents for the given Julian day.
 353  */
 354 void PersianCalendar::handleComputeFields(int32_t julianDay, UErrorCode &/*status*/) {
 355     int jy,jm,jd;
 356     julian_to_jalali(julianDay-1947955,&jy,&jm,&jd);
 357     internalSet(UCAL_ERA, 0);
 358     internalSet(UCAL_YEAR, jy);
 359     internalSet(UCAL_EXTENDED_YEAR, jy);
 360     internalSet(UCAL_MONTH, jm-1);
 361     internalSet(UCAL_DAY_OF_MONTH, jd);
 362     internalSet(UCAL_DAY_OF_YEAR, jd + MONTH_COUNT[jm-1][2]);
 363 }
 364
 365 UBool
 366 PersianCalendar::inDaylightTime(UErrorCode& status) const
 367 {
 368     // copied from GregorianCalendar
 369     if (U_FAILURE(status) || !getTimeZone().useDaylightTime())
 370         return FALSE;
 371
 372     // Force an update of the state of the Calendar.
 373     ((PersianCalendar*)this)->complete(status); // cast away const
 374
 375     return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE);
 376 }
 377
 378 // default century
 379 const UDate     PersianCalendar::fgSystemDefaultCentury        = DBL_MIN;
 380 const int32_t   PersianCalendar::fgSystemDefaultCenturyYear    = -1;
 381
 382 UDate           PersianCalendar::fgSystemDefaultCenturyStart       = DBL_MIN;
 383 int32_t         PersianCalendar::fgSystemDefaultCenturyStartYear   = -1;
 384
 385 UBool PersianCalendar::haveDefaultCentury() const
 386 {
 387     return TRUE;
 388 }
 389
 390 UDate PersianCalendar::defaultCenturyStart() const
 391 {
 392     return internalGetDefaultCenturyStart();
 393 }
 394
 395 int32_t PersianCalendar::defaultCenturyStartYear() const
 396 {
 397     return internalGetDefaultCenturyStartYear();
 398 }
 399
 400 UDate
 401 PersianCalendar::internalGetDefaultCenturyStart() const
 402 {
 403     // lazy-evaluate systemDefaultCenturyStart
 404     UBool needsUpdate;
 405     UMTX_CHECK(NULL, (fgSystemDefaultCenturyStart == fgSystemDefaultCentury), needsUpdate);
 406
 407     if (needsUpdate) {
 408         initializeSystemDefaultCentury();
 409     }
 410
 411     // use defaultCenturyStart unless it's the flag value;
 412     // then use systemDefaultCenturyStart
 413
 414     return fgSystemDefaultCenturyStart;
 415 }
 416
 417 int32_t
 418 PersianCalendar::internalGetDefaultCenturyStartYear() const
 419 {
 420     // lazy-evaluate systemDefaultCenturyStartYear
 421     UBool needsUpdate;
 422     UMTX_CHECK(NULL, (fgSystemDefaultCenturyStart == fgSystemDefaultCentury), needsUpdate);
 423
 424     if (needsUpdate) {
 425         initializeSystemDefaultCentury();
 426     }
 427
 428     // use defaultCenturyStart unless it's the flag value;
 429     // then use systemDefaultCenturyStartYear
 430
 431     return    fgSystemDefaultCenturyStartYear;
 432 }
 433
 434 void
 435 PersianCalendar::initializeSystemDefaultCentury()
 436 {
 437     // initialize systemDefaultCentury and systemDefaultCenturyYear based
 438     // on the current time.  They'll be set to 80 years before
 439     // the current time.
 440     UErrorCode status = U_ZERO_ERROR;
 441     PersianCalendar calendar(Locale("@calendar=persian"),status);
 442     if (U_SUCCESS(status))
 443     {
 444         calendar.setTime(Calendar::getNow(), status);
 445         calendar.add(UCAL_YEAR, -80, status);
 446         UDate    newStart =  calendar.getTime(status);
 447         int32_t  newYear  =  calendar.get(UCAL_YEAR, status);
 448         umtx_lock(NULL);
 449         if (fgSystemDefaultCenturyStart == fgSystemDefaultCentury)
 450         {
 451             fgSystemDefaultCenturyStartYear = newYear;
 452             fgSystemDefaultCenturyStart = newStart;
 453         }
 454         umtx_unlock(NULL);
 455     }
 456     // We have no recourse upon failure unless we want to propagate the failure
 457     // out.
 458 }
 459
 460 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(PersianCalendar)
 461
 462 U_NAMESPACE_END
 463
 464 #endif
 465