1 /*
2  ******************************************************************************
3  * Copyright (C) 2003-2013, 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  *   10/1/2012   roozbeh     Fixed algorithm and heavily refactored and rewrote
14  *                           based on the implementation of Gregorian
15  *****************************************************************************
16  */
17 
18 #include "persncal.h"
19 
20 #if !UCONFIG_NO_FORMATTING
21 
22 #include "umutex.h"
23 #include "gregoimp.h" // Math
24 #include <float.h>
25 
26 static const int16_t kPersianNumDays[]
27 = {0,31,62,93,124,155,186,216,246,276,306,336}; // 0-based, for day-in-year
28 static const int8_t kPersianMonthLength[]
29 = {31,31,31,31,31,31,30,30,30,30,30,29}; // 0-based
30 static const int8_t kPersianLeapMonthLength[]
31 = {31,31,31,31,31,31,30,30,30,30,30,30}; // 0-based
32 
33 static const int32_t kPersianCalendarLimits[UCAL_FIELD_COUNT][4] = {
34     // Minimum  Greatest     Least   Maximum
35     //           Minimum   Maximum
36     {        0,        0,        0,        0}, // ERA
37     { -5000000, -5000000,  5000000,  5000000}, // YEAR
38     {        0,        0,       11,       11}, // MONTH
39     {        1,        1,       52,       53}, // WEEK_OF_YEAR
40     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // WEEK_OF_MONTH
41     {        1,       1,        29,       31}, // DAY_OF_MONTH
42     {        1,       1,       365,      366}, // DAY_OF_YEAR
43     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DAY_OF_WEEK
44     {        1,       1,         5,        5}, // DAY_OF_WEEK_IN_MONTH
45     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // AM_PM
46     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR
47     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR_OF_DAY
48     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MINUTE
49     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // SECOND
50     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECOND
51     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // ZONE_OFFSET
52     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DST_OFFSET
53     { -5000000, -5000000,  5000000,  5000000}, // YEAR_WOY
54     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DOW_LOCAL
55     { -5000000, -5000000,  5000000,  5000000}, // EXTENDED_YEAR
56     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // JULIAN_DAY
57     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECONDS_IN_DAY
58     {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // IS_LEAP_MONTH
59 };
60 
61 U_NAMESPACE_BEGIN
62 
63 static const int32_t PERSIAN_EPOCH = 1948320;
64 
65 // Implementation of the PersianCalendar class
66 
67 //-------------------------------------------------------------------------
68 // Constructors...
69 //-------------------------------------------------------------------------
70 
getType() const71 const char *PersianCalendar::getType() const {
72     return "persian";
73 }
74 
clone() const75 Calendar* PersianCalendar::clone() const {
76     return new PersianCalendar(*this);
77 }
78 
PersianCalendar(const Locale & aLocale,UErrorCode & success)79 PersianCalendar::PersianCalendar(const Locale& aLocale, UErrorCode& success)
80   :   Calendar(TimeZone::createDefault(), aLocale, success)
81 {
82     setTimeInMillis(getNow(), success); // Call this again now that the vtable is set up properly.
83 }
84 
PersianCalendar(const PersianCalendar & other)85 PersianCalendar::PersianCalendar(const PersianCalendar& other) : Calendar(other) {
86 }
87 
~PersianCalendar()88 PersianCalendar::~PersianCalendar()
89 {
90 }
91 
92 //-------------------------------------------------------------------------
93 // Minimum / Maximum access functions
94 //-------------------------------------------------------------------------
95 
96 
handleGetLimit(UCalendarDateFields field,ELimitType limitType) const97 int32_t PersianCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const {
98     return kPersianCalendarLimits[field][limitType];
99 }
100 
101 //-------------------------------------------------------------------------
102 // Assorted calculation utilities
103 //
104 
105 /**
106  * Determine whether a year is a leap year in the Persian calendar
107  */
isLeapYear(int32_t year)108 UBool PersianCalendar::isLeapYear(int32_t year)
109 {
110     int32_t remainder;
111     ClockMath::floorDivide(25 * year + 11, 33, remainder);
112     return (remainder < 8);
113 }
114 
115 /**
116  * Return the day # on which the given year starts.  Days are counted
117  * from the Persian epoch, origin 0.
118  */
yearStart(int32_t year)119 int32_t PersianCalendar::yearStart(int32_t year) {
120     return handleComputeMonthStart(year,0,FALSE);
121 }
122 
123 /**
124  * Return the day # on which the given month starts.  Days are counted
125  * from the Persian epoch, origin 0.
126  *
127  * @param year  The Persian year
128  * @param year  The Persian month, 0-based
129  */
monthStart(int32_t year,int32_t month) const130 int32_t PersianCalendar::monthStart(int32_t year, int32_t month) const {
131     return handleComputeMonthStart(year,month,TRUE);
132 }
133 
134 //----------------------------------------------------------------------
135 // Calendar framework
136 //----------------------------------------------------------------------
137 
138 /**
139  * Return the length (in days) of the given month.
140  *
141  * @param year  The Persian year
142  * @param year  The Persian month, 0-based
143  */
handleGetMonthLength(int32_t extendedYear,int32_t month) const144 int32_t PersianCalendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const {
145     // If the month is out of range, adjust it into range, and
146     // modify the extended year value accordingly.
147     if (month < 0 || month > 11) {
148         extendedYear += ClockMath::floorDivide(month, 12, month);
149     }
150 
151     return isLeapYear(extendedYear) ? kPersianLeapMonthLength[month] : kPersianMonthLength[month];
152 }
153 
154 /**
155  * Return the number of days in the given Persian year
156  */
handleGetYearLength(int32_t extendedYear) const157 int32_t PersianCalendar::handleGetYearLength(int32_t extendedYear) const {
158     return isLeapYear(extendedYear) ? 366 : 365;
159 }
160 
161 //-------------------------------------------------------------------------
162 // Functions for converting from field values to milliseconds....
163 //-------------------------------------------------------------------------
164 
165 // Return JD of start of given month/year
handleComputeMonthStart(int32_t eyear,int32_t month,UBool) const166 int32_t PersianCalendar::handleComputeMonthStart(int32_t eyear, int32_t month, UBool /*useMonth*/) const {
167     // If the month is out of range, adjust it into range, and
168     // modify the extended year value accordingly.
169     if (month < 0 || month > 11) {
170         eyear += ClockMath::floorDivide(month, 12, month);
171     }
172 
173     int32_t julianDay = PERSIAN_EPOCH - 1 + 365 * (eyear - 1) + ClockMath::floorDivide(8 * eyear + 21, 33);
174 
175     if (month != 0) {
176         julianDay += kPersianNumDays[month];
177     }
178 
179     return julianDay;
180 }
181 
182 //-------------------------------------------------------------------------
183 // Functions for converting from milliseconds to field values
184 //-------------------------------------------------------------------------
185 
handleGetExtendedYear()186 int32_t PersianCalendar::handleGetExtendedYear() {
187     int32_t year;
188     if (newerField(UCAL_EXTENDED_YEAR, UCAL_YEAR) == UCAL_EXTENDED_YEAR) {
189         year = internalGet(UCAL_EXTENDED_YEAR, 1); // Default to year 1
190     } else {
191         year = internalGet(UCAL_YEAR, 1); // Default to year 1
192     }
193     return year;
194 }
195 
196 /**
197  * Override Calendar to compute several fields specific to the Persian
198  * calendar system.  These are:
199  *
200  * <ul><li>ERA
201  * <li>YEAR
202  * <li>MONTH
203  * <li>DAY_OF_MONTH
204  * <li>DAY_OF_YEAR
205  * <li>EXTENDED_YEAR</ul>
206  *
207  * The DAY_OF_WEEK and DOW_LOCAL fields are already set when this
208  * method is called.
209  */
handleComputeFields(int32_t julianDay,UErrorCode &)210 void PersianCalendar::handleComputeFields(int32_t julianDay, UErrorCode &/*status*/) {
211     int32_t year, month, dayOfMonth, dayOfYear;
212 
213     int32_t daysSinceEpoch = julianDay - PERSIAN_EPOCH;
214     year = 1 + ClockMath::floorDivide(33 * daysSinceEpoch + 3, 12053);
215 
216     int32_t farvardin1 = 365 * (year - 1) + ClockMath::floorDivide(8 * year + 21, 33);
217     dayOfYear = (daysSinceEpoch - farvardin1); // 0-based
218     if (dayOfYear < 216) { // Compute 0-based month
219         month = dayOfYear / 31;
220     } else {
221         month = (dayOfYear - 6) / 30;
222     }
223     dayOfMonth = dayOfYear - kPersianNumDays[month] + 1;
224     ++dayOfYear; // Make it 1-based now
225 
226     internalSet(UCAL_ERA, 0);
227     internalSet(UCAL_YEAR, year);
228     internalSet(UCAL_EXTENDED_YEAR, year);
229     internalSet(UCAL_MONTH, month);
230     internalSet(UCAL_DAY_OF_MONTH, dayOfMonth);
231     internalSet(UCAL_DAY_OF_YEAR, dayOfYear);
232 }
233 
234 UBool
inDaylightTime(UErrorCode & status) const235 PersianCalendar::inDaylightTime(UErrorCode& status) const
236 {
237     // copied from GregorianCalendar
238     if (U_FAILURE(status) || !getTimeZone().useDaylightTime())
239         return FALSE;
240 
241     // Force an update of the state of the Calendar.
242     ((PersianCalendar*)this)->complete(status); // cast away const
243 
244     return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE);
245 }
246 
247 // default century
248 
249 static UDate           gSystemDefaultCenturyStart       = DBL_MIN;
250 static int32_t         gSystemDefaultCenturyStartYear   = -1;
251 static icu::UInitOnce  gSystemDefaultCenturyInit        = U_INITONCE_INITIALIZER;
252 
haveDefaultCentury() const253 UBool PersianCalendar::haveDefaultCentury() const
254 {
255     return TRUE;
256 }
257 
initializeSystemDefaultCentury()258 static void U_CALLCONV initializeSystemDefaultCentury() {
259     // initialize systemDefaultCentury and systemDefaultCenturyYear based
260     // on the current time.  They'll be set to 80 years before
261     // the current time.
262     UErrorCode status = U_ZERO_ERROR;
263     PersianCalendar calendar(Locale("@calendar=persian"),status);
264     if (U_SUCCESS(status))
265     {
266         calendar.setTime(Calendar::getNow(), status);
267         calendar.add(UCAL_YEAR, -80, status);
268 
269         gSystemDefaultCenturyStart = calendar.getTime(status);
270         gSystemDefaultCenturyStartYear = calendar.get(UCAL_YEAR, status);
271     }
272     // We have no recourse upon failure unless we want to propagate the failure
273     // out.
274 }
275 
defaultCenturyStart() const276 UDate PersianCalendar::defaultCenturyStart() const {
277     // lazy-evaluate systemDefaultCenturyStart
278     umtx_initOnce(gSystemDefaultCenturyInit, &initializeSystemDefaultCentury);
279     return gSystemDefaultCenturyStart;
280 }
281 
defaultCenturyStartYear() const282 int32_t PersianCalendar::defaultCenturyStartYear() const {
283     // lazy-evaluate systemDefaultCenturyStartYear
284     umtx_initOnce(gSystemDefaultCenturyInit, &initializeSystemDefaultCentury);
285     return gSystemDefaultCenturyStartYear;
286 }
287 
288 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(PersianCalendar)
289 
290 U_NAMESPACE_END
291 
292 #endif
293 
294