/**
* Override Calendar to compute several fields specific to the Islamic
* 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.
* @draft ICU 2.4
*/
void IslamicCalendar::handleComputeFields(int32_t julianDay, UErrorCode & status)
{
int32_t year, month, dayOfMonth, dayOfYear;
UDate startDate;
int32_t days = julianDay - 1948440;
if (civil == CIVIL)
{
// Use the civil calendar approximation, which is just arithmetic
year = (int)ClockMath::floorDivide((double)(30 * days + 10646) , 10631.0);
month = (int32_t)uprv_ceil((days - 29 - yearStart(year)) / 29.5);
month = month < 11 ? month : 11;
startDate = monthStart(year, month);
}
else
{
// Guess at the number of elapsed full months since the epoch
int32_t months = (int32_t)uprv_floor((double)days / CalendarAstronomer::SYNODIC_MONTH);
startDate = uprv_floor(months * CalendarAstronomer::SYNODIC_MONTH);
double age = moonAge(internalGetTime(), status);
if (U_FAILURE(status))
{
status = U_MEMORY_ALLOCATION_ERROR;
return;
}
if (days - startDate >= 25 && age > 0)
{
// If we're near the end of the month, assume next month and search backwards
months++;
}
// Find out the last time that the new moon was actually visible at this longitude
// This returns midnight the night that the moon was visible at sunset.
while ((startDate = trueMonthStart(months)) > days)
{
// If it was after the date in question, back up a month and try again
months--;
}
year = months / 12 + 1;
month = months % 12;
}
dayOfMonth = (days - monthStart(year, month)) + 1;
// Now figure out the day of the year.
dayOfYear = (days - monthStart(year, 0) + 1);
internalSet(UCAL_ERA, 0);
internalSet(UCAL_YEAR, year);
internalSet(UCAL_EXTENDED_YEAR, year);
internalSet(UCAL_MONTH, month);
internalSet(UCAL_DAY_OF_MONTH, dayOfMonth);
internalSet(UCAL_DAY_OF_YEAR, dayOfYear);
}
UDate
GregorianCalendar::getEpochDay(UErrorCode& status)
{
complete(status);
// Divide by 1000 (convert to seconds) in order to prevent overflow when
// dealing with UDate(Long.MIN_VALUE) and UDate(Long.MAX_VALUE).
double wallSec = internalGetTime()/1000 + (internalGet(UCAL_ZONE_OFFSET) + internalGet(UCAL_DST_OFFSET))/1000;
return ClockMath::floorDivide(wallSec, kOneDay/1000.0);
}
void
GregorianCalendar::roll(UCalendarDateFields field, int32_t amount, UErrorCode& status)
{
if((amount == 0) || U_FAILURE(status)) {
return;
}
// J81 processing. (gregorian cutover)
UBool inCutoverMonth = FALSE;
int32_t cMonthLen=0; // 'c' for cutover; in days
int32_t cDayOfMonth=0; // no discontinuity: [0, cMonthLen)
double cMonthStart=0.0; // in ms
// Common code - see if we're in the cutover month of the cutover year
if(get(UCAL_EXTENDED_YEAR, status) == fGregorianCutoverYear) {
switch (field) {
case UCAL_DAY_OF_MONTH:
case UCAL_WEEK_OF_MONTH:
{
int32_t max = monthLength(internalGet(UCAL_MONTH));
UDate t = internalGetTime();
// We subtract 1 from the DAY_OF_MONTH to make it zero-based, and an
// additional 10 if we are after the cutover. Thus the monthStart
// value will be correct iff we actually are in the cutover month.
cDayOfMonth = internalGet(UCAL_DAY_OF_MONTH) - ((t >= fGregorianCutover) ? 10 : 0);
cMonthStart = t - ((cDayOfMonth - 1) * kOneDay);
// A month containing the cutover is 10 days shorter.
if ((cMonthStart < fGregorianCutover) &&
(cMonthStart + (cMonthLen=(max-10))*kOneDay >= fGregorianCutover)) {
inCutoverMonth = TRUE;
}
}
default:
;
}
}
switch (field) {
case UCAL_WEEK_OF_YEAR: {
// Unlike WEEK_OF_MONTH, WEEK_OF_YEAR never shifts the day of the
// week. Also, rolling the week of the year can have seemingly
// strange effects simply because the year of the week of year
// may be different from the calendar year. For example, the
// date Dec 28, 1997 is the first day of week 1 of 1998 (if
// weeks start on Sunday and the minimal days in first week is
// <= 3).
int32_t woy = get(UCAL_WEEK_OF_YEAR, status);
// Get the ISO year, which matches the week of year. This
// may be one year before or after the calendar year.
int32_t isoYear = get(UCAL_YEAR_WOY, status);
int32_t isoDoy = internalGet(UCAL_DAY_OF_YEAR);
if (internalGet(UCAL_MONTH) == UCAL_JANUARY) {
if (woy >= 52) {
isoDoy += handleGetYearLength(isoYear);
}
} else {
if (woy == 1) {
isoDoy -= handleGetYearLength(isoYear - 1);
}
}
woy += amount;
// Do fast checks to avoid unnecessary computation:
if (woy < 1 || woy > 52) {
// Determine the last week of the ISO year.
// We do this using the standard formula we use
// everywhere in this file. If we can see that the
// days at the end of the year are going to fall into
// week 1 of the next year, we drop the last week by
// subtracting 7 from the last day of the year.
int32_t lastDoy = handleGetYearLength(isoYear);
int32_t lastRelDow = (lastDoy - isoDoy + internalGet(UCAL_DAY_OF_WEEK) -
getFirstDayOfWeek()) % 7;
if (lastRelDow < 0) lastRelDow += 7;
if ((6 - lastRelDow) >= getMinimalDaysInFirstWeek()) lastDoy -= 7;
int32_t lastWoy = weekNumber(lastDoy, lastRelDow + 1);
woy = ((woy + lastWoy - 1) % lastWoy) + 1;
}
set(UCAL_WEEK_OF_YEAR, woy);
set(UCAL_YEAR_WOY,isoYear);
return;
}
case UCAL_DAY_OF_MONTH:
if( !inCutoverMonth ) {
Calendar::roll(field, amount, status);
return;
} else {
// [j81] 1582 special case for DOM
// The default computation works except when the current month
// contains the Gregorian cutover. We handle this special case
// here. [j81 - aliu]
double monthLen = cMonthLen * kOneDay;
double msIntoMonth = uprv_fmod(internalGetTime() - cMonthStart +
amount * kOneDay, monthLen);
if (msIntoMonth < 0) {
msIntoMonth += monthLen;
}
#if defined (U_DEBUG_CAL)
fprintf(stderr, "%s:%d: roll DOM %d -> %.0lf ms \n",
__FILE__, __LINE__,amount, cMonthLen, cMonthStart+msIntoMonth);
#endif
setTimeInMillis(cMonthStart + msIntoMonth, status);
return;
}
case UCAL_WEEK_OF_MONTH:
if( !inCutoverMonth ) {
Calendar::roll(field, amount, status);
return;
} else {
#if defined (U_DEBUG_CAL)
fprintf(stderr, "%s:%d: roll WOM %d ??????????????????? \n",
__FILE__, __LINE__,amount);
#endif
// NOTE: following copied from the old
// GregorianCalendar::roll( WEEK_OF_MONTH ) code
// This is tricky, because during the roll we may have to shift
// to a different day of the week. For example:
// s m t w r f s
// 1 2 3 4 5
// 6 7 8 9 10 11 12
// When rolling from the 6th or 7th back one week, we go to the
// 1st (assuming that the first partial week counts). The same
// thing happens at the end of the month.
// The other tricky thing is that we have to figure out whether
// the first partial week actually counts or not, based on the
// minimal first days in the week. And we have to use the
// correct first day of the week to delineate the week
// boundaries.
// Here's our algorithm. First, we find the real boundaries of
// the month. Then we discard the first partial week if it
// doesn't count in this locale. Then we fill in the ends with
// phantom days, so that the first partial week and the last
// partial week are full weeks. We then have a nice square
// block of weeks. We do the usual rolling within this block,
// as is done elsewhere in this method. If we wind up on one of
// the phantom days that we added, we recognize this and pin to
// the first or the last day of the month. Easy, eh?
// Another wrinkle: To fix jitterbug 81, we have to make all this
// work in the oddball month containing the Gregorian cutover.
// This month is 10 days shorter than usual, and also contains
// a discontinuity in the days; e.g., the default cutover month
// is Oct 1582, and goes from day of month 4 to day of month 15.
// Normalize the DAY_OF_WEEK so that 0 is the first day of the week
// in this locale. We have dow in 0..6.
int32_t dow = internalGet(UCAL_DAY_OF_WEEK) - getFirstDayOfWeek();
if (dow < 0)
dow += 7;
// Find the day of month, compensating for cutover discontinuity.
int32_t dom = cDayOfMonth;
// Find the day of the week (normalized for locale) for the first
// of the month.
int32_t fdm = (dow - dom + 1) % 7;
if (fdm < 0)
fdm += 7;
// Get the first day of the first full week of the month,
// including phantom days, if any. Figure out if the first week
// counts or not; if it counts, then fill in phantom days. If
// not, advance to the first real full week (skip the partial week).
int32_t start;
if ((7 - fdm) < getMinimalDaysInFirstWeek())
start = 8 - fdm; // Skip the first partial week
else
start = 1 - fdm; // This may be zero or negative
// Get the day of the week (normalized for locale) for the last
// day of the month.
int32_t monthLen = cMonthLen;
int32_t ldm = (monthLen - dom + dow) % 7;
// We know monthLen >= DAY_OF_MONTH so we skip the += 7 step here.
// Get the limit day for the blocked-off rectangular month; that
// is, the day which is one past the last day of the month,
// after the month has already been filled in with phantom days
// to fill out the last week. This day has a normalized DOW of 0.
int32_t limit = monthLen + 7 - ldm;
// Now roll between start and (limit - 1).
int32_t gap = limit - start;
int32_t newDom = (dom + amount*7 - start) % gap;
if (newDom < 0)
newDom += gap;
newDom += start;
// Finally, pin to the real start and end of the month.
if (newDom < 1)
newDom = 1;
if (newDom > monthLen)
newDom = monthLen;
// Set the DAY_OF_MONTH. We rely on the fact that this field
// takes precedence over everything else (since all other fields
// are also set at this point). If this fact changes (if the
// disambiguation algorithm changes) then we will have to unset
// the appropriate fields here so that DAY_OF_MONTH is attended
// to.
// If we are in the cutover month, manipulate ms directly. Don't do
// this in general because it doesn't work across DST boundaries
// (details, details). This takes care of the discontinuity.
setTimeInMillis(cMonthStart + (newDom-1)*kOneDay, status);
return;
}
default:
Calendar::roll(field, amount, status);
return;
}
}
/**
* Override Calendar to compute several fields specific to the Islamic
* 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.
* @draft ICU 2.4
*/
void IslamicCalendar::handleComputeFields(int32_t julianDay, UErrorCode &status) {
int32_t year, month, dayOfMonth, dayOfYear;
int32_t startDate;
int32_t days = julianDay - CIVIL_EPOC;
if (cType == CIVIL || cType == TBLA) {
if(cType == TBLA) {
days = julianDay - ASTRONOMICAL_EPOC;
}
// Use the civil calendar approximation, which is just arithmetic
year = (int)ClockMath::floorDivide( (double)(30 * days + 10646) , 10631.0 );
month = (int32_t)uprv_ceil((days - 29 - yearStart(year)) / 29.5 );
month = month<11?month:11;
startDate = monthStart(year, month);
} else if(cType == ASTRONOMICAL){
// Guess at the number of elapsed full months since the epoch
int32_t months = (int32_t)uprv_floor((double)days / CalendarAstronomer::SYNODIC_MONTH);
startDate = (int32_t)uprv_floor(months * CalendarAstronomer::SYNODIC_MONTH);
double age = moonAge(internalGetTime(), status);
if (U_FAILURE(status)) {
status = U_MEMORY_ALLOCATION_ERROR;
return;
}
if ( days - startDate >= 25 && age > 0) {
// If we're near the end of the month, assume next month and search backwards
months++;
}
// Find out the last time that the new moon was actually visible at this longitude
// This returns midnight the night that the moon was visible at sunset.
while ((startDate = trueMonthStart(months)) > days) {
// If it was after the date in question, back up a month and try again
months--;
}
year = months / 12 + 1;
month = months % 12;
} else if(cType == UMALQURA) {
int32_t umalquraStartdays = yearStart(UMALQURA_YEAR_START) ;
if( days < umalquraStartdays){
//Use Civil calculation
year = (int)ClockMath::floorDivide( (double)(30 * days + 10646) , 10631.0 );
month = (int32_t)uprv_ceil((days - 29 - yearStart(year)) / 29.5 );
month = month<11?month:11;
startDate = monthStart(year, month);
}else{
int y =UMALQURA_YEAR_START-1, m =0;
long d = 1;
while(d > 0){
y++;
d = days - yearStart(y) +1;
if(d == handleGetYearLength(y)){
m=11;
break;
}else if(d < handleGetYearLength(y) ){
int monthLen = handleGetMonthLength(y, m);
m=0;
while(d > monthLen){
d -= monthLen;
m++;
monthLen = handleGetMonthLength(y, m);
}
break;
}
}
year = y;
month = m;
}
} else { // invalid 'civil'
U_ASSERT(false); // should not get here, out of range
year=month=0;
}
dayOfMonth = (days - monthStart(year, month)) + 1;
// Now figure out the day of the year.
dayOfYear = (days - monthStart(year, 0)) + 1;
internalSet(UCAL_ERA, 0);
internalSet(UCAL_YEAR, year);
internalSet(UCAL_EXTENDED_YEAR, year);
internalSet(UCAL_MONTH, month);
internalSet(UCAL_DAY_OF_MONTH, dayOfMonth);
internalSet(UCAL_DAY_OF_YEAR, dayOfYear);
}
