1/*
2******************************************************************************
3* Copyright (C) 2003-2013, International Business Machines Corporation
4* and others. All Rights Reserved.
5******************************************************************************
6*
7* File ISLAMCAL.H
8*
9* Modification History:
10*
11*   Date        Name        Description
12*   10/14/2003  srl         ported from java IslamicCalendar
13*****************************************************************************
14*/
15
16#include "islamcal.h"
17
18#if !UCONFIG_NO_FORMATTING
19
20#include "umutex.h"
21#include <float.h>
22#include "gregoimp.h" // Math
23#include "astro.h" // CalendarAstronomer
24#include "uhash.h"
25#include "ucln_in.h"
26#include "uassert.h"
27
28static const UDate HIJRA_MILLIS = -42521587200000.0;    // 7/16/622 AD 00:00
29
30// Debugging
31#ifdef U_DEBUG_ISLAMCAL
32# include <stdio.h>
33# include <stdarg.h>
34static void debug_islamcal_loc(const char *f, int32_t l)
35{
36    fprintf(stderr, "%s:%d: ", f, l);
37}
38
39static void debug_islamcal_msg(const char *pat, ...)
40{
41    va_list ap;
42    va_start(ap, pat);
43    vfprintf(stderr, pat, ap);
44    fflush(stderr);
45}
46// must use double parens, i.e.:  U_DEBUG_ISLAMCAL_MSG(("four is: %d",4));
47#define U_DEBUG_ISLAMCAL_MSG(x) {debug_islamcal_loc(__FILE__,__LINE__);debug_islamcal_msg x;}
48#else
49#define U_DEBUG_ISLAMCAL_MSG(x)
50#endif
51
52
53// --- The cache --
54// cache of months
55static UMutex astroLock = U_MUTEX_INITIALIZER;  // pod bay door lock
56static icu::CalendarCache *gMonthCache = NULL;
57static icu::CalendarAstronomer *gIslamicCalendarAstro = NULL;
58
59U_CDECL_BEGIN
60static UBool calendar_islamic_cleanup(void) {
61    if (gMonthCache) {
62        delete gMonthCache;
63        gMonthCache = NULL;
64    }
65    if (gIslamicCalendarAstro) {
66        delete gIslamicCalendarAstro;
67        gIslamicCalendarAstro = NULL;
68    }
69    return TRUE;
70}
71U_CDECL_END
72
73U_NAMESPACE_BEGIN
74
75// Implementation of the IslamicCalendar class
76
77/**
78 * Friday EPOC
79 */
80static const int32_t CIVIL_EPOC = 1948440; // CE 622 July 16 Friday (Julian calendar) / CE 622 July 19 (Gregorian calendar)
81
82/**
83  * Thursday EPOC
84  */
85static const int32_t ASTRONOMICAL_EPOC = 1948439; // CE 622 July 15 Thursday (Julian calendar)
86
87
88static const int32_t UMALQURA_YEAR_START = 1318;
89static const int32_t UMALQURA_YEAR_END = 1480;
90
91static const int UMALQURA_MONTHLENGTH[] = {
92    //* 1318 -1322 */ "1011 0110 1010", "1001 0111 0101", "0100 1010 1110", "1010 0100 1111", "0101 0010 1011",
93                            0x0B6A,           0x0975,           0x04AE,           0x0A4F,           0x052B,
94    //* 1323 -1327 */ "0110 1001 0101", "0110 1100 1010", "1010 1101 0101", "0010 1101 0110", "1001 0101 1011",
95                            0x0695,           0x06CA,           0x0AD5,           0x02D6,           0x095B,
96    //* 1328 -1332 */ "1001 0010 1101", "1100 1001 0101", "1101 0100 1010", "1101 1001 0101", "0110 1101 0010",
97                            0x092D,           0x0C95,           0x0D4A,           0x0D95,           0x025B,
98    //* 1333 -1337 */ "1010 1101 0101", "0101 0101 1010", "1010 1010 1011", "0101 0010 1011", "0110 1010 0101",
99                            0x0AD5,           0x055A,           0x0AAB,           0x052B,           0x06A5,
100    //* 1338 -1342 */ "0111 0101 0010", "1011 1010 1001", "0011 0111 0100", "1010 1011 0110", "0101 0101 0110",
101                            0x0752,           0x0BA9,           0x0374,           0x0AB6,           0x0556,
102    //* 1343 -1347 */ "1010 1010 1010", "1101 0101 0010", "1011 1010 0100", "1011 1101 0010", "1010 1110 1010",
103                            0x0AAA,           0x0D52,           0x0BA4,           0x0BD2,           0x0AEA,
104    //* 1348 -1352 */ "0010 1101 1100", "1001 0110 1101", "1001 0010 1110", "1010 1010 0110", "1101 0101 0100",
105                            0x02DC,           0x096D,           0x092E,           0x0AA6,           0x0D54,
106    //* 1353 -1357 */ "1011 1010 0101", "0101 1011 0100", "1001 1011 0110", "1001 0011 0111", "0100 1001 1011",
107                            0x0BA5,           0x05B4,           0x09B6,           0x0937,           0x049B,
108    //* 1358 -1362 */ "1010 0100 1011", "1011 0010 0101", "1011 0101 0100", "1011 0110 1010", "0101 0110 1010",
109                            0x0A4B,           0x0B25,           0x0B54,           0x0B6A,           0x056A,
110    //* 1363 -1367 */ "1010 1010 1011", "1010 0101 0101", "1101 0010 0101", "1110 1001 0010", "1110 1100 1001",
111                            0x0AAB,           0x0A55,           0x0D25,           0x0E92,           0x0EC9,
112    //* 1368 -1372 */ "0110 1101 0100", "1010 1110 1010", "0101 0110 1011", "0100 1010 1011", "1001 0100 1011",
113                            0x06D4,           0x0ADA,           0x056B,           0x04AB,           0x094B,
114    //* 1373 -1377 */ "1011 0100 1001", "1011 1010 0100", "1011 1011 0010", "0101 1011 0101", "0010 1011 1010",
115                            0x0B49,           0x0BA4,           0x0BB2,           0x05B5,           0x02BA,
116    //* 1378 -1382 */ "1001 0101 1011", "0100 1010 1011", "0101 0101 0101", "0110 1011 0010", "0101 1011 0100",
117                            0x095B,           0x04AB,           0x0555,           0x06B2,           0x05B4,
118    //* 1383 -1387 */ "1001 1101 1010", "1001 0110 1110", "0100 1010 1110", "1010 0101 0110", "1101 0010 1010",
119                            0x09DA,           0x096E,           0x04AE,           0x0A56,           0x0D2A,
120    //* 1388 -1392 */ "1101 0101 0100", "1101 1011 0010", "1010 1011 0101", "0010 1101 1010", "1001 0101 1011",
121                            0x0D54,           0x0DB2,           0x0AB5,           0x02DA,           0x095B,
122    //* 1393 -1397 */ "1001 0010 1011", "1010 1001 0101", "1011 0100 1001", "1011 0110 0100", "1011 0111 0001",
123                            0x092B,           0x0A95,           0x0B49,           0x0B64,           0x0B71,
124    //* 1398 -1402 */ "0101 1011 0100", "1010 1011 0101", "1010 1001 0110", "1101 0100 1010", "1110 1001 0010",
125                            0x05B4,           0x0AB5,           0x0A96,           0x0B4A,           0x0E92,
126    //* 1403 -1407 */ "1110 1100 1001", "0110 1101 0100", "1010 1110 1001", "1010 1010 1101", "0101 0101 0101",
127                            0x0EC9,           0x06D4,           0x0AE9,           0x0AAD,           0x0555,
128    //* 1408 -1412 */ "1010 1010 0101", "1011 0101 0010", "1101 1010 0100", "1101 1011 0010", "1001 1011 1010",
129                            0x0AA5,           0x0B52,           0x0DA4,           0x0DB2,           0x09BA,
130    //* 1413 -1417 */ "0100 1011 1010", "1010 0101 1011", "0101 0010 1101", "1010 1010 0101", "1010 1101 0100",
131                            0x04BA,           0x0A5B,           0x052D,           0x0AA5,           0x0AD4,
132    //* 1418 -1422 */ "1010 1110 1010", "0101 0101 1100", "0100 1011 1101", "0010 0011 1101", "1001 0001 1101",
133                            0x0AEA,           0x055C,           0x04BD,           0x023D,           0x091D,
134    //* 1423 -1427 */ "1010 1001 0101", "1011 0100 1010", "1011 0101 1010", "0101 0110 1101", "0010 1011 0110",
135                            0x0A95,           0x0B4A,           0x0B5A,           0x056D,           0x02B6,
136    //* 1428 -1432 */ "1001 0011 1011", "0100 1001 1011", "0110 0101 0101", "0110 1010 1001", "0111 0101 0100",
137                            0x093B,           0x049B,           0x0655,           0x06A9,           0x0754,
138    //* 1433 -1437 */ "1011 0110 1010", "0101 0110 1100", "1010 1010 1101", "0101 0101 0101", "1011 0010 1001",
139                            0x0B6A,           0x056C,           0x0AAD,           0x0555,           0x0B29,
140    //* 1438 -1442 */ "1011 1001 0010", "1011 1010 1001", "0101 1101 0100", "1010 1101 1010", "0101 0101 1010",
141                            0x0B92,           0x0BA9,           0x05D4,           0x0ADA,           0x055A,
142    //* 1443 -1447 */ "1010 1010 1011", "0101 1001 0101", "0111 0100 1001", "0111 0110 0100", "1011 1010 1010",
143                            0x0AAB,           0x0595,           0x0749,           0x0764,           0x0BAA,
144    //* 1448 -1452 */ "0101 1011 0101", "0010 1011 0110", "1010 0101 0110", "1110 0100 1101", "1011 0010 0101",
145                            0x05B5,           0x02B6,           0x0A56,           0x0E4D,           0x0B25,
146    //* 1453 -1457 */ "1011 0101 0010", "1011 0110 1010", "0101 1010 1101", "0010 1010 1110", "1001 0010 1111",
147                            0x0B52,           0x0B6A,           0x05AD,           0x02AE,           0x092F,
148    //* 1458 -1462 */ "0100 1001 0111", "0110 0100 1011", "0110 1010 0101", "0110 1010 1100", "1010 1101 0110",
149                            0x0497,           0x064B,           0x06A5,           0x06AC,           0x0AD6,
150    //* 1463 -1467 */ "0101 0101 1101", "0100 1001 1101", "1010 0100 1101", "1101 0001 0110", "1101 1001 0101",
151                            0x055D,           0x049D,           0x0A4D,           0x0D16,           0x0D95,
152    //* 1468 -1472 */ "0101 1010 1010", "0101 1011 0101", "0010 1101 1010", "1001 0101 1011", "0100 1010 1101",
153                            0x05AA,           0x05B5,           0x02DA,           0x095B,           0x04AD,
154    //* 1473 -1477 */ "0101 1001 0101", "0110 1100 1010", "0110 1110 0100", "1010 1110 1010", "0100 1111 0101",
155                            0x0595,           0x06CA,           0x06E4,           0x0AEA,           0x04F5,
156    //* 1478 -1480 */ "0010 1011 0110", "1001 0101 0110", "1010 1010 1010"
157                            0x02B6,           0x0956,           0x0AAA
158};
159
160int32_t getUmalqura_MonthLength(int32_t y, int32_t m) {
161    int32_t mask = (int32_t) (0x01 << (11 - m));    // set mask for bit corresponding to month
162    if((UMALQURA_MONTHLENGTH[y] & mask) == 0 )
163        return 29;
164    else
165        return 30;
166
167}
168
169//-------------------------------------------------------------------------
170// Constructors...
171//-------------------------------------------------------------------------
172
173const char *IslamicCalendar::getType() const {
174    const char *sType = NULL;
175
176    switch (cType) {
177    case CIVIL:
178        sType = "islamic-civil";
179        break;
180    case ASTRONOMICAL:
181        sType = "islamic";
182        break;
183    case TBLA:
184        sType = "islamic-tbla";
185        break;
186    case UMALQURA:
187        sType = "islamic-umalqura";
188        break;
189    default:
190        U_ASSERT(false); // out of range
191        sType = "islamic";  // "islamic" is used as the generic type
192        break;
193    }
194    return sType;
195}
196
197Calendar* IslamicCalendar::clone() const {
198    return new IslamicCalendar(*this);
199}
200
201IslamicCalendar::IslamicCalendar(const Locale& aLocale, UErrorCode& success, ECalculationType type)
202:   Calendar(TimeZone::createDefault(), aLocale, success),
203cType(type)
204{
205    setTimeInMillis(getNow(), success); // Call this again now that the vtable is set up properly.
206}
207
208IslamicCalendar::IslamicCalendar(const IslamicCalendar& other) : Calendar(other), cType(other.cType) {
209}
210
211IslamicCalendar::~IslamicCalendar()
212{
213}
214
215void IslamicCalendar::setCalculationType(ECalculationType type, UErrorCode &status)
216{
217    if (cType != type) {
218        // The fields of the calendar will become invalid, because the calendar
219        // rules are different
220        UDate m = getTimeInMillis(status);
221        cType = type;
222        clear();
223        setTimeInMillis(m, status);
224    }
225}
226
227/**
228* Returns <code>true</code> if this object is using the fixed-cycle civil
229* calendar, or <code>false</code> if using the religious, astronomical
230* calendar.
231* @draft ICU 2.4
232*/
233UBool IslamicCalendar::isCivil() {
234    return (cType == CIVIL);
235}
236
237//-------------------------------------------------------------------------
238// Minimum / Maximum access functions
239//-------------------------------------------------------------------------
240
241// Note: Current IslamicCalendar implementation does not work
242// well with negative years.
243
244// TODO: In some cases the current ICU Islamic calendar implementation shows
245// a month as having 31 days. Since date parsing now uses range checks based
246// on the table below, we need to change the range for last day of month to
247// include 31 as a workaround until the implementation is fixed.
248static const int32_t LIMITS[UCAL_FIELD_COUNT][4] = {
249    // Minimum  Greatest    Least  Maximum
250    //           Minimum  Maximum
251    {        0,        0,        0,        0}, // ERA
252    {        1,        1,  5000000,  5000000}, // YEAR
253    {        0,        0,       11,       11}, // MONTH
254    {        1,        1,       50,       51}, // WEEK_OF_YEAR
255    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // WEEK_OF_MONTH
256    {        1,        1,       29,       31}, // DAY_OF_MONTH - 31 to workaround for cal implementation bug, should be 30
257    {        1,        1,      354,      355}, // DAY_OF_YEAR
258    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DAY_OF_WEEK
259    {       -1,       -1,        5,        5}, // DAY_OF_WEEK_IN_MONTH
260    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // AM_PM
261    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR
262    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR_OF_DAY
263    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MINUTE
264    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // SECOND
265    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECOND
266    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // ZONE_OFFSET
267    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DST_OFFSET
268    {        1,        1,  5000000,  5000000}, // YEAR_WOY
269    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DOW_LOCAL
270    {        1,        1,  5000000,  5000000}, // EXTENDED_YEAR
271    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // JULIAN_DAY
272    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECONDS_IN_DAY
273    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // IS_LEAP_MONTH
274};
275
276/**
277* @draft ICU 2.4
278*/
279int32_t IslamicCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const {
280    return LIMITS[field][limitType];
281}
282
283//-------------------------------------------------------------------------
284// Assorted calculation utilities
285//
286
287// table mapping extended year to julian day
288// for year start in the Umm-Al-Qura calendar.
289// 660 bytes
290static const int32_t jdForUmAlQuraYrStart[] = {
291//  jdIsUm     isYr
292    466700, // 1318
293    467055, // 1319
294    467410, // 1320
295    467764, // 1321
296    468119, // 1322
297    468473, // 1323
298    468827, // 1324
299    469181, // 1325
300    469536, // 1326
301    469890, // 1327
302    470245, // 1328
303    470599, // 1329
304    470953, // 1330
305    471307, // 1331
306    471662, // 1332
307    472016, // 1333
308    472371, // 1334
309    472725, // 1335
310    473080, // 1336
311    473434, // 1337
312    473788, // 1338
313    474142, // 1339
314    474497, // 1340
315    474851, // 1341
316    475206, // 1342
317    475560, // 1343
318    475914, // 1344
319    476268, // 1345
320    476622, // 1346
321    476977, // 1347
322    477332, // 1348
323    477686, // 1349
324    478041, // 1350
325    478395, // 1351
326    478749, // 1352
327    479103, // 1353
328    479458, // 1354
329    479812, // 1355
330    480167, // 1356
331    480522, // 1357
332    480876, // 1358
333    481230, // 1359
334    481584, // 1360
335    481938, // 1361
336    482293, // 1362
337    482647, // 1363
338    483002, // 1364
339    483356, // 1365
340    483710, // 1366
341    484064, // 1367
342    484419, // 1368
343    484773, // 1369
344    485128, // 1370
345    485483, // 1371
346    485837, // 1372
347    486191, // 1373
348    486545, // 1374
349    486899, // 1375
350    487254, // 1376
351    487609, // 1377
352    487963, // 1378
353    488318, // 1379
354    488672, // 1380
355    489026, // 1381
356    489380, // 1382
357    489734, // 1383
358    490089, // 1384
359    490444, // 1385
360    490798, // 1386
361    491152, // 1387
362    491506, // 1388
363    491860, // 1389
364    492215, // 1390
365    492570, // 1391
366    492924, // 1392
367    493279, // 1393
368    493633, // 1394
369    493987, // 1395
370    494341, // 1396
371    494695, // 1397
372    495050, // 1398
373    495404, // 1399
374    495759, // 1400
375    496113, // 1401
376    496467, // 1402
377    496821, // 1403
378    497176, // 1404
379    497530, // 1405
380    497885, // 1406
381    498240, // 1407
382    498594, // 1408
383    498948, // 1409
384    499302, // 1410
385    499656, // 1411
386    500011, // 1412
387    500366, // 1413
388    500720, // 1414
389    501075, // 1415
390    501429, // 1416
391    501783, // 1417
392    502137, // 1418
393    502492, // 1419
394    502846, // 1420
395    503201, // 1421
396    503555, // 1422
397    503909, // 1423
398    504263, // 1424
399    504617, // 1425
400    504972, // 1426
401    505327, // 1427
402    505681, // 1428
403    506036, // 1429
404    506390, // 1430
405    506744, // 1431
406    507098, // 1432
407    507452, // 1433
408    507807, // 1434
409    508161, // 1435
410    508516, // 1436
411    508870, // 1437
412    509224, // 1438
413    509578, // 1439
414    509933, // 1440
415    510287, // 1441
416    510642, // 1442
417    510996, // 1443
418    511351, // 1444
419    511705, // 1445
420    512059, // 1446
421    512413, // 1447
422    512768, // 1448
423    513123, // 1449
424    513477, // 1450
425    513831, // 1451
426    514186, // 1452
427    514540, // 1453
428    514894, // 1454
429    515249, // 1455
430    515604, // 1456
431    515958, // 1457
432    516313, // 1458
433    516667, // 1459
434    517021, // 1460
435    517375, // 1461
436    517729, // 1462
437    518084, // 1463
438    518439, // 1464
439    518793, // 1465
440    519147, // 1466
441    519501, // 1467
442    519856, // 1468
443    520210, // 1469
444    520565, // 1470
445    520919, // 1471
446    521274, // 1472
447    521628, // 1473
448    521982, // 1474
449    522336, // 1475
450    522690, // 1476
451    523045, // 1477
452    523400, // 1478
453    523754, // 1479
454    524108, // 1480
455};
456
457/**
458* Determine whether a year is a leap year in the Islamic civil calendar
459*/
460UBool IslamicCalendar::civilLeapYear(int32_t year)
461{
462    return (14 + 11 * year) % 30 < 11;
463}
464
465/**
466* Return the day # on which the given year starts.  Days are counted
467* from the Hijri epoch, origin 0.
468*/
469int32_t IslamicCalendar::yearStart(int32_t year) const{
470    if (cType == CIVIL || cType == TBLA ||
471        (cType == UMALQURA && (year < UMALQURA_YEAR_START || year > UMALQURA_YEAR_END)))
472    {
473        // The following is similar to part of
474        // Dershowitz & Reingold, 3rd ed., formula 6.3
475        // adjusted to give day offset within current epoch.
476        return (year-1)*354 + ClockMath::floorDivide((3+11*year),30);
477    } else if(cType==ASTRONOMICAL){
478        return trueMonthStart(12*(year-1));
479    } else {
480        return jdForUmAlQuraYrStart[year - UMALQURA_YEAR_START];
481    }
482}
483
484/**
485* Return the day # on which the given month starts.  Days are counted
486* from the Hijri epoch, origin 0.
487*
488* @param year  The hijri year
489* @param year  The hijri month, 0-based (assumed to be in range 0..11)
490*/
491int32_t IslamicCalendar::monthStart(int32_t year, int32_t month) const {
492    if (cType == CIVIL || cType == TBLA) {
493        // The following is similar to part of
494        // Dershowitz & Reingold, 3rd ed., formula 6.3
495        // adjusted for 0-based months and to give day offset within current epoch.
496        // This does not handle months out of the range 0..11
497        return (year-1)*354 + (int32_t)ClockMath::floorDivide((3+11*year),30) +
498            (int32_t)uprv_ceil(29.5*month);
499    } else if(cType==ASTRONOMICAL){
500        return trueMonthStart(12*(year-1) + month);
501    } else {
502        int32_t ms = yearStart(year);
503        for(int i=0; i< month; i++){
504            ms+= handleGetMonthLength(year, i);
505        }
506        return ms;
507    }
508}
509
510/**
511* Find the day number on which a particular month of the true/lunar
512* Islamic calendar starts.
513*
514* @param month The month in question, origin 0 from the Hijri epoch
515*
516* @return The day number on which the given month starts.
517*/
518int32_t IslamicCalendar::trueMonthStart(int32_t month) const
519{
520    UErrorCode status = U_ZERO_ERROR;
521    int32_t start = CalendarCache::get(&gMonthCache, month, status);
522
523    if (start==0) {
524        // Make a guess at when the month started, using the average length
525        UDate origin = HIJRA_MILLIS
526            + uprv_floor(month * CalendarAstronomer::SYNODIC_MONTH) * kOneDay;
527
528        // moonAge will fail due to memory allocation error
529        double age = moonAge(origin, status);
530        if (U_FAILURE(status)) {
531            goto trueMonthStartEnd;
532        }
533
534        if (age >= 0) {
535            // The month has already started
536            do {
537                origin -= kOneDay;
538                age = moonAge(origin, status);
539                if (U_FAILURE(status)) {
540                    goto trueMonthStartEnd;
541                }
542            } while (age >= 0);
543        }
544        else {
545            // Preceding month has not ended yet.
546            do {
547                origin += kOneDay;
548                age = moonAge(origin, status);
549                if (U_FAILURE(status)) {
550                    goto trueMonthStartEnd;
551                }
552            } while (age < 0);
553        }
554        start = (int32_t)ClockMath::floorDivide((origin - HIJRA_MILLIS), (double)kOneDay) + 1;
555        CalendarCache::put(&gMonthCache, month, start, status);
556    }
557trueMonthStartEnd :
558    if(U_FAILURE(status)) {
559        start = 0;
560    }
561    return start;
562}
563
564/**
565* Return the "age" of the moon at the given time; this is the difference
566* in ecliptic latitude between the moon and the sun.  This method simply
567* calls CalendarAstronomer.moonAge, converts to degrees,
568* and adjusts the result to be in the range [-180, 180].
569*
570* @param time  The time at which the moon's age is desired,
571*              in millis since 1/1/1970.
572*/
573double IslamicCalendar::moonAge(UDate time, UErrorCode &status)
574{
575    double age = 0;
576
577    umtx_lock(&astroLock);
578    if(gIslamicCalendarAstro == NULL) {
579        gIslamicCalendarAstro = new CalendarAstronomer();
580        if (gIslamicCalendarAstro == NULL) {
581            status = U_MEMORY_ALLOCATION_ERROR;
582            return age;
583        }
584        ucln_i18n_registerCleanup(UCLN_I18N_ISLAMIC_CALENDAR, calendar_islamic_cleanup);
585    }
586    gIslamicCalendarAstro->setTime(time);
587    age = gIslamicCalendarAstro->getMoonAge();
588    umtx_unlock(&astroLock);
589
590    // Convert to degrees and normalize...
591    age = age * 180 / CalendarAstronomer::PI;
592    if (age > 180) {
593        age = age - 360;
594    }
595
596    return age;
597}
598
599//----------------------------------------------------------------------
600// Calendar framework
601//----------------------------------------------------------------------
602
603/**
604* Return the length (in days) of the given month.
605*
606* @param year  The hijri year
607* @param year  The hijri month, 0-based
608* @draft ICU 2.4
609*/
610int32_t IslamicCalendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const {
611
612    int32_t length = 0;
613
614    if (cType == CIVIL || cType == TBLA ||
615        (cType == UMALQURA && (extendedYear<UMALQURA_YEAR_START || extendedYear>UMALQURA_YEAR_END)) ) {
616        length = 29 + (month+1) % 2;
617        if (month == DHU_AL_HIJJAH && civilLeapYear(extendedYear)) {
618            length++;
619        }
620    } else if(cType == ASTRONOMICAL){
621        month = 12*(extendedYear-1) + month;
622        length =  trueMonthStart(month+1) - trueMonthStart(month) ;
623    } else {
624        length = getUmalqura_MonthLength(extendedYear - UMALQURA_YEAR_START, month);
625    }
626    return length;
627}
628
629/**
630* Return the number of days in the given Islamic year
631* @draft ICU 2.4
632*/
633int32_t IslamicCalendar::handleGetYearLength(int32_t extendedYear) const {
634    if (cType == CIVIL || cType == TBLA ||
635        (cType == UMALQURA && (extendedYear<UMALQURA_YEAR_START || extendedYear>UMALQURA_YEAR_END)) ) {
636        return 354 + (civilLeapYear(extendedYear) ? 1 : 0);
637    } else if(cType == ASTRONOMICAL){
638        int32_t month = 12*(extendedYear-1);
639        return (trueMonthStart(month + 12) - trueMonthStart(month));
640    } else {
641        int len = 0;
642        for(int i=0; i<12; i++) {
643            len += handleGetMonthLength(extendedYear, i);
644        }
645        return len;
646    }
647}
648
649//-------------------------------------------------------------------------
650// Functions for converting from field values to milliseconds....
651//-------------------------------------------------------------------------
652
653// Return JD of start of given month/year
654// Calendar says:
655// Get the Julian day of the day BEFORE the start of this year.
656// If useMonth is true, get the day before the start of the month.
657// Hence the -1
658/**
659* @draft ICU 2.4
660*/
661int32_t IslamicCalendar::handleComputeMonthStart(int32_t eyear, int32_t month, UBool /* useMonth */) const {
662    // This may be called by Calendar::handleComputeJulianDay with months out of the range
663    // 0..11. Need to handle that here since monthStart requires months in the range 0.11.
664    if (month > 11) {
665        eyear += (month / 12);
666        month %= 12;
667    } else if (month < 0) {
668        month++;
669        eyear += (month / 12) - 1;
670        month = (month % 12) + 11;
671    }
672    return monthStart(eyear, month) + ((cType == TBLA)? ASTRONOMICAL_EPOC: CIVIL_EPOC) - 1;
673}
674
675//-------------------------------------------------------------------------
676// Functions for converting from milliseconds to field values
677//-------------------------------------------------------------------------
678
679/**
680* @draft ICU 2.4
681*/
682int32_t IslamicCalendar::handleGetExtendedYear() {
683    int32_t year;
684    if (newerField(UCAL_EXTENDED_YEAR, UCAL_YEAR) == UCAL_EXTENDED_YEAR) {
685        year = internalGet(UCAL_EXTENDED_YEAR, 1); // Default to year 1
686    } else {
687        year = internalGet(UCAL_YEAR, 1); // Default to year 1
688    }
689    return year;
690}
691
692/**
693* Override Calendar to compute several fields specific to the Islamic
694* calendar system.  These are:
695*
696* <ul><li>ERA
697* <li>YEAR
698* <li>MONTH
699* <li>DAY_OF_MONTH
700* <li>DAY_OF_YEAR
701* <li>EXTENDED_YEAR</ul>
702*
703* The DAY_OF_WEEK and DOW_LOCAL fields are already set when this
704* method is called. The getGregorianXxx() methods return Gregorian
705* calendar equivalents for the given Julian day.
706* @draft ICU 2.4
707*/
708void IslamicCalendar::handleComputeFields(int32_t julianDay, UErrorCode &status) {
709    int32_t year, month, dayOfMonth, dayOfYear;
710    int32_t startDate;
711    int32_t days = julianDay - CIVIL_EPOC;
712
713    if (cType == CIVIL || cType == TBLA) {
714        if(cType == TBLA) {
715            days = julianDay - ASTRONOMICAL_EPOC;
716        }
717        // Use the civil calendar approximation, which is just arithmetic.
718        // The following is similar to part of
719        // Dershowitz & Reingold, 3rd ed., formula 6.4
720        year  = (int)ClockMath::floorDivide( (double)(30 * days + 10646) , 10631.0 );
721        month = (int32_t)uprv_ceil((days - 29 - yearStart(year)) / 29.5 );
722        month = month<11?month:11;
723        startDate = monthStart(year, month);
724    } else if(cType == ASTRONOMICAL){
725        // Guess at the number of elapsed full months since the epoch
726        int32_t months = (int32_t)uprv_floor((double)days / CalendarAstronomer::SYNODIC_MONTH);
727
728        startDate = (int32_t)uprv_floor(months * CalendarAstronomer::SYNODIC_MONTH);
729
730        double age = moonAge(internalGetTime(), status);
731        if (U_FAILURE(status)) {
732            status = U_MEMORY_ALLOCATION_ERROR;
733            return;
734        }
735        if ( days - startDate >= 25 && age > 0) {
736            // If we're near the end of the month, assume next month and search backwards
737            months++;
738        }
739
740        // Find out the last time that the new moon was actually visible at this longitude
741        // This returns midnight the night that the moon was visible at sunset.
742        while ((startDate = trueMonthStart(months)) > days) {
743            // If it was after the date in question, back up a month and try again
744            months--;
745        }
746
747        year = months / 12 + 1;
748        month = months % 12;
749    } else if(cType == UMALQURA) {
750        int32_t umalquraStartdays = yearStart(UMALQURA_YEAR_START) ;
751        if( days < umalquraStartdays){
752                //Use Civil calculation
753                year  = (int)ClockMath::floorDivide( (double)(30 * days + 10646) , 10631.0 );
754                month = (int32_t)uprv_ceil((days - 29 - yearStart(year)) / 29.5 );
755                month = month<11?month:11;
756                startDate = monthStart(year, month);
757            }else{
758                int y =UMALQURA_YEAR_START-1, m =0;
759                long d = 1;
760                while(d > 0){
761                    y++;
762                    d = days - yearStart(y) +1;
763                    if(d == handleGetYearLength(y)){
764                        m=11;
765                        break;
766                    }else if(d < handleGetYearLength(y) ){
767                        int monthLen = handleGetMonthLength(y, m);
768                        m=0;
769                        while(d > monthLen){
770                            d -= monthLen;
771                            m++;
772                            monthLen = handleGetMonthLength(y, m);
773                        }
774                        break;
775                    }
776                }
777                year = y;
778                month = m;
779            }
780    } else { // invalid 'civil'
781      U_ASSERT(false); // should not get here, out of range
782      year=month=0;
783    }
784
785    dayOfMonth = (days - monthStart(year, month)) + 1;
786
787    // Now figure out the day of the year.
788    dayOfYear = (days - monthStart(year, 0)) + 1;
789
790
791    internalSet(UCAL_ERA, 0);
792    internalSet(UCAL_YEAR, year);
793    internalSet(UCAL_EXTENDED_YEAR, year);
794    internalSet(UCAL_MONTH, month);
795    internalSet(UCAL_DAY_OF_MONTH, dayOfMonth);
796    internalSet(UCAL_DAY_OF_YEAR, dayOfYear);
797}
798
799UBool
800IslamicCalendar::inDaylightTime(UErrorCode& status) const
801{
802    // copied from GregorianCalendar
803    if (U_FAILURE(status) || (&(getTimeZone()) == NULL && !getTimeZone().useDaylightTime()))
804        return FALSE;
805
806    // Force an update of the state of the Calendar.
807    ((IslamicCalendar*)this)->complete(status); // cast away const
808
809    return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE);
810}
811
812/**
813 * The system maintains a static default century start date and Year.  They are
814 * initialized the first time they are used.  Once the system default century date
815 * and year are set, they do not change.
816 */
817static UDate           gSystemDefaultCenturyStart       = DBL_MIN;
818static int32_t         gSystemDefaultCenturyStartYear   = -1;
819static icu::UInitOnce  gSystemDefaultCenturyInit        = U_INITONCE_INITIALIZER;
820
821
822UBool IslamicCalendar::haveDefaultCentury() const
823{
824    return TRUE;
825}
826
827UDate IslamicCalendar::defaultCenturyStart() const
828{
829    // lazy-evaluate systemDefaultCenturyStart
830    umtx_initOnce(gSystemDefaultCenturyInit, &initializeSystemDefaultCentury);
831    return gSystemDefaultCenturyStart;
832}
833
834int32_t IslamicCalendar::defaultCenturyStartYear() const
835{
836    // lazy-evaluate systemDefaultCenturyStartYear
837    umtx_initOnce(gSystemDefaultCenturyInit, &initializeSystemDefaultCentury);
838    return gSystemDefaultCenturyStartYear;
839}
840
841
842void U_CALLCONV
843IslamicCalendar::initializeSystemDefaultCentury()
844{
845    // initialize systemDefaultCentury and systemDefaultCenturyYear based
846    // on the current time.  They'll be set to 80 years before
847    // the current time.
848    UErrorCode status = U_ZERO_ERROR;
849    IslamicCalendar calendar(Locale("@calendar=islamic-civil"),status);
850    if (U_SUCCESS(status)) {
851        calendar.setTime(Calendar::getNow(), status);
852        calendar.add(UCAL_YEAR, -80, status);
853
854        gSystemDefaultCenturyStart = calendar.getTime(status);
855        gSystemDefaultCenturyStartYear = calendar.get(UCAL_YEAR, status);
856    }
857    // We have no recourse upon failure unless we want to propagate the failure
858    // out.
859}
860
861
862
863UOBJECT_DEFINE_RTTI_IMPLEMENTATION(IslamicCalendar)
864
865U_NAMESPACE_END
866
867#endif
868
869