1 files changed, 309 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/japancal.cpp b/intl/icu/source/i18n/japancal.cpp
new file mode 100644
index 0000000000..fc18d6c0eb
--- /dev/null
+++ b/intl/icu/source/i18n/japancal.cpp
@@ -0,0 +1,309 @@
+// © 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+/*
+*******************************************************************************
+* Copyright (C) 2003-2009,2012,2016 International Business Machines Corporation and
+* others. All Rights Reserved.
+*******************************************************************************
+*
+* File JAPANCAL.CPP
+*
+* Modification History:
+*  05/16/2003    srl     copied from buddhcal.cpp
+*
+*/
+
+#include "unicode/utypes.h"
+
+#if !UCONFIG_NO_FORMATTING
+#if U_PLATFORM_HAS_WINUWP_API == 0
+#include <stdlib.h> // getenv() is not available in UWP env
+#else
+#ifndef WIN32_LEAN_AND_MEAN
+#   define WIN32_LEAN_AND_MEAN
+#endif
+#   define VC_EXTRALEAN
+#   define NOUSER
+#   define NOSERVICE
+#   define NOIME
+#   define NOMCX
+#include <windows.h>
+#endif
+#include "cmemory.h"
+#include "erarules.h"
+#include "japancal.h"
+#include "unicode/gregocal.h"
+#include "umutex.h"
+#include "uassert.h"
+#include "ucln_in.h"
+#include "cstring.h"
+
+static icu::EraRules * gJapaneseEraRules = nullptr;
+static icu::UInitOnce gJapaneseEraRulesInitOnce {};
+static int32_t gCurrentEra = 0;
+
+U_CDECL_BEGIN
+static UBool japanese_calendar_cleanup() {
+    if (gJapaneseEraRules) {
+        delete gJapaneseEraRules;
+        gJapaneseEraRules = nullptr;
+    }
+    gCurrentEra = 0;
+    gJapaneseEraRulesInitOnce.reset();
+    return true;
+}
+U_CDECL_END
+
+U_NAMESPACE_BEGIN
+
+UOBJECT_DEFINE_RTTI_IMPLEMENTATION(JapaneseCalendar)
+
+static const int32_t kGregorianEpoch = 1970;    // used as the default value of EXTENDED_YEAR
+static const char* TENTATIVE_ERA_VAR_NAME = "ICU_ENABLE_TENTATIVE_ERA";
+
+
+// Export the following for use by test code.
+UBool JapaneseCalendar::enableTentativeEra() {
+    // Although start date of next Japanese era is planned ahead, a name of
+    // new era might not be available. This implementation allows tester to
+    // check a new era without era names by settings below (in priority order).
+    // By default, such tentative era is disabled.
+
+    // 1. Environment variable ICU_ENABLE_TENTATIVE_ERA=true or false
+
+    UBool includeTentativeEra = false;
+
+#if U_PLATFORM_HAS_WINUWP_API == 1
+    // UWP doesn't allow access to getenv(), but we can call GetEnvironmentVariableW to do the same thing.
+    char16_t varName[26] = {};
+    u_charsToUChars(TENTATIVE_ERA_VAR_NAME, varName, static_cast<int32_t>(uprv_strlen(TENTATIVE_ERA_VAR_NAME)));
+    WCHAR varValue[5] = {};
+    DWORD ret = GetEnvironmentVariableW(reinterpret_cast<WCHAR*>(varName), varValue, UPRV_LENGTHOF(varValue));
+    if ((ret == 4) && (_wcsicmp(varValue, L"true") == 0)) {
+        includeTentativeEra = true;
+    }
+#else
+    char *envVarVal = getenv(TENTATIVE_ERA_VAR_NAME);
+    if (envVarVal != nullptr && uprv_stricmp(envVarVal, "true") == 0) {
+        includeTentativeEra = true;
+    }
+#endif
+    return includeTentativeEra;
+}
+
+
+// Initialize global Japanese era data
+static void U_CALLCONV initializeEras(UErrorCode &status) {
+    gJapaneseEraRules = EraRules::createInstance("japanese", JapaneseCalendar::enableTentativeEra(), status);
+    if (U_FAILURE(status)) {
+        return;
+    }
+    gCurrentEra = gJapaneseEraRules->getCurrentEraIndex();
+}
+
+static void init(UErrorCode &status) {
+    umtx_initOnce(gJapaneseEraRulesInitOnce, &initializeEras, status);
+    ucln_i18n_registerCleanup(UCLN_I18N_JAPANESE_CALENDAR, japanese_calendar_cleanup);
+}
+
+/* Some platforms don't like to export constants, like old Palm OS and some z/OS configurations. */
+uint32_t JapaneseCalendar::getCurrentEra() {
+    return gCurrentEra;
+}
+
+JapaneseCalendar::JapaneseCalendar(const Locale& aLocale, UErrorCode& success)
+:   GregorianCalendar(aLocale, success)
+{
+    init(success);
+    setTimeInMillis(getNow(), success); // Call this again now that the vtable is set up properly.
+}
+
+JapaneseCalendar::~JapaneseCalendar()
+{
+}
+
+JapaneseCalendar::JapaneseCalendar(const JapaneseCalendar& source)
+: GregorianCalendar(source)
+{
+    UErrorCode status = U_ZERO_ERROR;
+    init(status);
+    U_ASSERT(U_SUCCESS(status));
+}
+
+JapaneseCalendar& JapaneseCalendar::operator= ( const JapaneseCalendar& right)
+{
+    GregorianCalendar::operator=(right);
+    return *this;
+}
+
+JapaneseCalendar* JapaneseCalendar::clone() const
+{
+    return new JapaneseCalendar(*this);
+}
+
+const char *JapaneseCalendar::getType() const
+{
+    return "japanese";
+}
+
+int32_t JapaneseCalendar::getDefaultMonthInYear(int32_t eyear) 
+{
+    int32_t era = internalGetEra();
+    // TODO do we assume we can trust 'era'?  What if it is denormalized?
+
+    int32_t month = 0;
+
+    // Find out if we are at the edge of an era
+    int32_t eraStart[3] = { 0,0,0 };
+    UErrorCode status = U_ZERO_ERROR;
+    gJapaneseEraRules->getStartDate(era, eraStart, status);
+    U_ASSERT(U_SUCCESS(status));
+    if(eyear == eraStart[0]) {
+        // Yes, we're in the first year of this era.
+        return eraStart[1]  // month
+                -1;         // return 0-based month
+    }
+
+    return month;
+}
+
+int32_t JapaneseCalendar::getDefaultDayInMonth(int32_t eyear, int32_t month) 
+{
+    int32_t era = internalGetEra();
+    int32_t day = 1;
+
+    int32_t eraStart[3] = { 0,0,0 };
+    UErrorCode status = U_ZERO_ERROR;
+    gJapaneseEraRules->getStartDate(era, eraStart, status);
+    U_ASSERT(U_SUCCESS(status));
+    if(eyear == eraStart[0]) {
+        if(month == eraStart[1] - 1) {
+            return eraStart[2];
+        }
+    }
+
+    return day;
+}
+
+
+int32_t JapaneseCalendar::internalGetEra() const
+{
+    return internalGet(UCAL_ERA, gCurrentEra);
+}
+
+int32_t JapaneseCalendar::handleGetExtendedYear()
+{
+    // EXTENDED_YEAR in JapaneseCalendar is a Gregorian year
+    // The default value of EXTENDED_YEAR is 1970 (Showa 45)
+    int32_t year;
+
+    if (newerField(UCAL_EXTENDED_YEAR, UCAL_YEAR) == UCAL_EXTENDED_YEAR &&
+        newerField(UCAL_EXTENDED_YEAR, UCAL_ERA) == UCAL_EXTENDED_YEAR) {
+        year = internalGet(UCAL_EXTENDED_YEAR, kGregorianEpoch);
+    } else {
+        UErrorCode status = U_ZERO_ERROR;
+        int32_t eraStartYear = gJapaneseEraRules->getStartYear(internalGet(UCAL_ERA, gCurrentEra), status);
+        U_ASSERT(U_SUCCESS(status));
+
+        // extended year is a gregorian year, where 1 = 1AD,  0 = 1BC, -1 = 2BC, etc
+        year = internalGet(UCAL_YEAR, 1)    // pin to minimum of year 1 (first year)
+            + eraStartYear                  // add gregorian starting year
+            - 1;                            // Subtract one because year starts at 1
+    }
+    return year;
+}
+
+
+void JapaneseCalendar::handleComputeFields(int32_t julianDay, UErrorCode& status)
+{
+    //Calendar::timeToFields(theTime, quick, status);
+    GregorianCalendar::handleComputeFields(julianDay, status);
+    int32_t year = internalGet(UCAL_EXTENDED_YEAR); // Gregorian year
+    int32_t eraIdx = gJapaneseEraRules->getEraIndex(year, internalGetMonth() + 1, internalGet(UCAL_DAY_OF_MONTH), status);
+
+    internalSet(UCAL_ERA, eraIdx);
+    internalSet(UCAL_YEAR, year - gJapaneseEraRules->getStartYear(eraIdx, status) + 1);
+}
+
+/*
+Disable pivoting 
+*/
+UBool JapaneseCalendar::haveDefaultCentury() const
+{
+    return false;
+}
+
+UDate JapaneseCalendar::defaultCenturyStart() const
+{
+    return 0;// WRONG
+}
+
+int32_t JapaneseCalendar::defaultCenturyStartYear() const
+{
+    return 0;
+}
+
+int32_t JapaneseCalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const
+{
+    switch(field) {
+    case UCAL_ERA:
+        if (limitType == UCAL_LIMIT_MINIMUM || limitType == UCAL_LIMIT_GREATEST_MINIMUM) {
+            return 0;
+        }
+        return gJapaneseEraRules->getNumberOfEras() - 1; // max known era, not gCurrentEra
+    case UCAL_YEAR:
+        {
+            switch (limitType) {
+            case UCAL_LIMIT_MINIMUM:
+            case UCAL_LIMIT_GREATEST_MINIMUM:
+                return 1;
+            case UCAL_LIMIT_LEAST_MAXIMUM:
+                return 1;
+            case  UCAL_LIMIT_COUNT: //added to avoid warning
+            case UCAL_LIMIT_MAXIMUM:
+            {
+                UErrorCode status = U_ZERO_ERROR;
+                int32_t eraStartYear = gJapaneseEraRules->getStartYear(gCurrentEra, status);
+                U_ASSERT(U_SUCCESS(status));
+                return GregorianCalendar::handleGetLimit(UCAL_YEAR, UCAL_LIMIT_MAXIMUM) - eraStartYear;
+            }
+            default:
+                return 1;    // Error condition, invalid limitType
+            }
+        }
+    default:
+        return GregorianCalendar::handleGetLimit(field,limitType);
+    }
+}
+
+int32_t JapaneseCalendar::getActualMaximum(UCalendarDateFields field, UErrorCode& status) const {
+    if (field == UCAL_YEAR) {
+        int32_t era = get(UCAL_ERA, status);
+        if (U_FAILURE(status)) {
+            return 0; // error case... any value
+        }
+        if (era == gJapaneseEraRules->getNumberOfEras() - 1) { // max known era, not gCurrentEra
+            // TODO: Investigate what value should be used here - revisit after 4.0.
+            return handleGetLimit(UCAL_YEAR, UCAL_LIMIT_MAXIMUM);
+        } else {
+            int32_t nextEraStart[3] = { 0,0,0 };
+            gJapaneseEraRules->getStartDate(era + 1, nextEraStart, status);
+            int32_t nextEraYear = nextEraStart[0];
+            int32_t nextEraMonth = nextEraStart[1]; // 1-base
+            int32_t nextEraDate = nextEraStart[2];
+
+            int32_t eraStartYear = gJapaneseEraRules->getStartYear(era, status);
+            int32_t maxYear = nextEraYear - eraStartYear + 1;   // 1-base
+            if (nextEraMonth == 1 && nextEraDate == 1) {
+                // Subtract 1, because the next era starts at Jan 1
+                maxYear--;
+            }
+            return maxYear;
+        }
+    }
+    return GregorianCalendar::getActualMaximum(field, status);
+}
+
+U_NAMESPACE_END
+
+#endif