// 返回阳历y年日差天数为x时所对应的月日数（如y=2000，x=274时，返回1001(表示10月1日，即返回100*m+d)）
static double antiDayDifference(int y, double x)
{
int m = 1;
for (int j = 1; j <= 12; j++)
{
int mL = dayDifference(y, j + 1, 1) - dayDifference(y, j, 1);
if (x <= mL || j == 12)
{
m = j;
break;
}
else
x -= mL;
}
return 100 * m + x;
}
// 返回等效标准天数（y年m月d日相应历种的1年1月1日的等效(即对Gregorian历与Julian历是统一的)天数）
static double equivalentStandardDay(int y, int m, int d)
{
//Julian的等效标准天数
double v = (y - 1) * 365 + floor((double)((y - 1) / 4)) + dayDifference(y, m, d) - 2;
if (y > 1582)
{//Gregorian的等效标准天数
v += -floor((double)((y - 1) / 100)) + floor((double)((y - 1) / 400)) + 2;
}
return v;
}
UnicodeString& RelativeDateFormat::format( Calendar& cal,
UnicodeString& appendTo,
FieldPosition& pos) const {
UErrorCode status = U_ZERO_ERROR;
UChar emptyStr = 0;
UnicodeString dateString(&emptyStr);
// calculate the difference, in days, between 'cal' and now.
int dayDiff = dayDifference(cal, status);
// look up string
int32_t len = 0;
const UChar *theString = getStringForDay(dayDiff, len, status);
if(U_SUCCESS(status) && (theString!=NULL)) {
// found a relative string
dateString.setTo(theString, len);
}
if(fTimeFormat == NULL || fCombinedFormat == 0) {
if (dateString.length() > 0) {
appendTo.append(dateString);
} else if(fDateFormat != NULL) {
fDateFormat->format(cal,appendTo,pos);
}
} else {
if (dateString.length() == 0 && fDateFormat != NULL) {
fDateFormat->format(cal,dateString,pos);
}
UnicodeString timeString(&emptyStr);
FieldPosition timepos = pos;
fTimeFormat->format(cal,timeString,timepos);
Formattable timeDateStrings[] = { timeString, dateString };
fCombinedFormat->format(timeDateStrings, 2, appendTo, pos, status); // pos is ignored by this
int32_t offset;
if (pos.getEndIndex() > 0 && (offset = appendTo.indexOf(dateString)) >= 0) {
// pos.field was found in dateString, offset start & end based on final position of dateString
pos.setBeginIndex( pos.getBeginIndex() + offset );
pos.setEndIndex( pos.getEndIndex() + offset );
} else if (timepos.getEndIndex() > 0 && (offset = appendTo.indexOf(timeString)) >= 0) {
// pos.field was found in timeString, offset start & end based on final position of timeString
pos.setBeginIndex( timepos.getBeginIndex() + offset );
pos.setEndIndex( timepos.getEndIndex() + offset );
}
}
return appendTo;
}
UnicodeString& RelativeDateFormat::format( Calendar& cal,
UnicodeString& appendTo,
FieldPosition& pos) const {
UErrorCode status = U_ZERO_ERROR;
UnicodeString relativeDayString;
UDisplayContext capitalizationContext = getContext(UDISPCTX_TYPE_CAPITALIZATION, status);
// calculate the difference, in days, between 'cal' and now.
int dayDiff = dayDifference(cal, status);
// look up string
int32_t len = 0;
const UChar *theString = getStringForDay(dayDiff, len, status);
if(U_SUCCESS(status) && (theString!=NULL)) {
// found a relative string
relativeDayString.setTo(theString, len);
}
if ( relativeDayString.length() > 0 && !fDatePattern.isEmpty() &&
(fTimePattern.isEmpty() || fCombinedFormat == NULL || fCombinedHasDateAtStart)) {
#if !UCONFIG_NO_BREAK_ITERATION
// capitalize relativeDayString according to context for relative, set formatter no context
if ( u_islower(relativeDayString.char32At(0)) && fCapitalizationBrkIter!= NULL &&
( capitalizationContext==UDISPCTX_CAPITALIZATION_FOR_BEGINNING_OF_SENTENCE ||
(capitalizationContext==UDISPCTX_CAPITALIZATION_FOR_UI_LIST_OR_MENU && fCapitalizationOfRelativeUnitsForUIListMenu) ||
(capitalizationContext==UDISPCTX_CAPITALIZATION_FOR_STANDALONE && fCapitalizationOfRelativeUnitsForStandAlone) ) ) {
// titlecase first word of relativeDayString
relativeDayString.toTitle(fCapitalizationBrkIter, fLocale, U_TITLECASE_NO_LOWERCASE | U_TITLECASE_NO_BREAK_ADJUSTMENT);
}
#endif
fDateTimeFormatter->setContext(UDISPCTX_CAPITALIZATION_NONE, status);
} else {
// set our context for the formatter
fDateTimeFormatter->setContext(capitalizationContext, status);
}
if (fDatePattern.isEmpty()) {
fDateTimeFormatter->applyPattern(fTimePattern);
fDateTimeFormatter->format(cal,appendTo,pos);
} else if (fTimePattern.isEmpty() || fCombinedFormat == NULL) {
if (relativeDayString.length() > 0) {
appendTo.append(relativeDayString);
} else {
fDateTimeFormatter->applyPattern(fDatePattern);
fDateTimeFormatter->format(cal,appendTo,pos);
}
} else {
UnicodeString datePattern;
if (relativeDayString.length() > 0) {
// Need to quote the relativeDayString to make it a legal date pattern
relativeDayString.findAndReplace(UNICODE_STRING("'", 1), UNICODE_STRING("''", 2)); // double any existing APOSTROPHE
relativeDayString.insert(0, APOSTROPHE); // add APOSTROPHE at beginning...
relativeDayString.append(APOSTROPHE); // and at end
datePattern.setTo(relativeDayString);
} else {
datePattern.setTo(fDatePattern);
}
UnicodeString combinedPattern;
fCombinedFormat->format(fTimePattern, datePattern, combinedPattern, status);
fDateTimeFormatter->applyPattern(combinedPattern);
fDateTimeFormatter->format(cal,appendTo,pos);
}
return appendTo;
}
