1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4 ******************************************************************************
5 * Copyright (C) 2013, International Business Machines Corporation
6 * and others. All Rights Reserved.
7 ******************************************************************************
8 *
9 * File DANGICAL.CPP
10 *****************************************************************************
11 */
12
13 #include "chnsecal.h"
14 #include "dangical.h"
15
16 #if !UCONFIG_NO_FORMATTING
17
18 #include "astro.h" // CalendarCache
19 #include "gregoimp.h" // Math
20 #include "uassert.h"
21 #include "ucln_in.h"
22 #include "umutex.h"
23 #include "unicode/rbtz.h"
24 #include "unicode/tzrule.h"
25
26 // --- The cache --
27 // Lazy Creation & Access synchronized by class CalendarCache with a mutex.
28 static icu::CalendarCache *gWinterSolsticeCache = nullptr;
29 static icu::CalendarCache *gNewYearCache = nullptr;
30
31 // gAstronomerTimeZone
32 static icu::TimeZone *gAstronomerTimeZone = nullptr;
33 static icu::UInitOnce gAstronomerTimeZoneInitOnce {};
34
35 /**
36 * The start year of the Korean traditional calendar (Dan-gi) is the inaugural
37 * year of Dan-gun (BC 2333).
38 */
39 static const int32_t DANGI_EPOCH_YEAR = -2332; // Gregorian year
40
41 U_CDECL_BEGIN
calendar_dangi_cleanup()42 static UBool calendar_dangi_cleanup() {
43 if (gWinterSolsticeCache) {
44 delete gWinterSolsticeCache;
45 gWinterSolsticeCache = nullptr;
46 }
47 if (gNewYearCache) {
48 delete gNewYearCache;
49 gNewYearCache = nullptr;
50 }
51
52 if (gAstronomerTimeZone) {
53 delete gAstronomerTimeZone;
54 gAstronomerTimeZone = nullptr;
55 }
56 gAstronomerTimeZoneInitOnce.reset();
57 return true;
58 }
59 U_CDECL_END
60
61 U_NAMESPACE_BEGIN
62
63 // Implementation of the DangiCalendar class
64
65 //-------------------------------------------------------------------------
66 // Constructors...
67 //-------------------------------------------------------------------------
68
69 const TimeZone* getAstronomerTimeZone(UErrorCode &status);
70
DangiCalendar(const Locale & aLocale,UErrorCode & success)71 DangiCalendar::DangiCalendar(const Locale& aLocale, UErrorCode& success)
72 : ChineseCalendar(aLocale, success)
73 {
74 }
75
DangiCalendar(const DangiCalendar & other)76 DangiCalendar::DangiCalendar (const DangiCalendar& other)
77 : ChineseCalendar(other)
78 {
79 }
80
~DangiCalendar()81 DangiCalendar::~DangiCalendar()
82 {
83 }
84
85 DangiCalendar*
clone() const86 DangiCalendar::clone() const
87 {
88 return new DangiCalendar(*this);
89 }
90
getType() const91 const char *DangiCalendar::getType() const {
92 return "dangi";
93 }
94
95 /**
96 * The time zone used for performing astronomical computations for
97 * Dangi calendar. In Korea various timezones have been used historically
98 * (cf. http://www.math.snu.ac.kr/~kye/others/lunar.html):
99 *
100 * - 1908/04/01: GMT+8
101 * 1908/04/01 - 1911/12/31: GMT+8.5
102 * 1912/01/01 - 1954/03/20: GMT+9
103 * 1954/03/21 - 1961/08/09: GMT+8.5
104 * 1961/08/10 - : GMT+9
105 *
106 * Note that, in 1908-1911, the government did not apply the timezone change
107 * but used GMT+8. In addition, 1954-1961's timezone change does not affect
108 * the lunar date calculation. Therefore, the following simpler rule works:
109 *
110 * -1911: GMT+8
111 * 1912-: GMT+9
112 *
113 * Unfortunately, our astronomer's approximation doesn't agree with the
114 * references (http://www.math.snu.ac.kr/~kye/others/lunar.html and
115 * http://astro.kasi.re.kr/Life/ConvertSolarLunarForm.aspx?MenuID=115)
116 * in 1897/7/30. So the following ad hoc fix is used here:
117 *
118 * -1896: GMT+8
119 * 1897: GMT+7
120 * 1898-1911: GMT+8
121 * 1912- : GMT+9
122 */
initAstronomerTimeZone(UErrorCode & status)123 static void U_CALLCONV initAstronomerTimeZone(UErrorCode &status) {
124 U_ASSERT(gAstronomerTimeZone == nullptr);
125 const UDate millis1897[] = { static_cast<UDate>((1897 - 1970) * 365 * kOneDay) }; // some days of error is not a problem here
126 const UDate millis1898[] = { static_cast<UDate>((1898 - 1970) * 365 * kOneDay) }; // some days of error is not a problem here
127 const UDate millis1912[] = { static_cast<UDate>((1912 - 1970) * 365 * kOneDay) }; // this doesn't create an issue for 1911/12/20
128 LocalPointer<InitialTimeZoneRule> initialTimeZone(new InitialTimeZoneRule(
129 UnicodeString(u"GMT+8"), 8*kOneHour, 0), status);
130
131 LocalPointer<TimeZoneRule> rule1897(new TimeArrayTimeZoneRule(
132 UnicodeString(u"Korean 1897"), 7*kOneHour, 0, millis1897, 1, DateTimeRule::STANDARD_TIME), status);
133
134 LocalPointer<TimeZoneRule> rule1898to1911(new TimeArrayTimeZoneRule(
135 UnicodeString(u"Korean 1898-1911"), 8*kOneHour, 0, millis1898, 1, DateTimeRule::STANDARD_TIME), status);
136
137 LocalPointer<TimeZoneRule> ruleFrom1912(new TimeArrayTimeZoneRule(
138 UnicodeString(u"Korean 1912-"), 9*kOneHour, 0, millis1912, 1, DateTimeRule::STANDARD_TIME), status);
139
140 LocalPointer<RuleBasedTimeZone> zone(new RuleBasedTimeZone(
141 UnicodeString(u"KOREA_ZONE"), initialTimeZone.orphan()), status); // adopts initialTimeZone
142
143 if (U_FAILURE(status)) {
144 return;
145 }
146 zone->addTransitionRule(rule1897.orphan(), status); // adopts rule1897
147 zone->addTransitionRule(rule1898to1911.orphan(), status);
148 zone->addTransitionRule(ruleFrom1912.orphan(), status);
149 zone->complete(status);
150 if (U_SUCCESS(status)) {
151 gAstronomerTimeZone = zone.orphan();
152 }
153 ucln_i18n_registerCleanup(UCLN_I18N_DANGI_CALENDAR, calendar_dangi_cleanup);
154 }
155
getAstronomerTimeZone(UErrorCode & status)156 const TimeZone* getAstronomerTimeZone(UErrorCode &status) {
157 umtx_initOnce(gAstronomerTimeZoneInitOnce, &initAstronomerTimeZone, status);
158 return gAstronomerTimeZone;
159 }
160
161 constexpr uint32_t kDangiRelatedYearDiff = -2333;
162
getRelatedYear(UErrorCode & status) const163 int32_t DangiCalendar::getRelatedYear(UErrorCode &status) const
164 {
165 int32_t year = get(UCAL_EXTENDED_YEAR, status);
166 if (U_FAILURE(status)) {
167 return 0;
168 }
169 if (uprv_add32_overflow(year, kDangiRelatedYearDiff, &year)) {
170 status = U_ILLEGAL_ARGUMENT_ERROR;
171 return 0;
172 }
173 return year;
174 }
175
setRelatedYear(int32_t year)176 void DangiCalendar::setRelatedYear(int32_t year)
177 {
178 // set extended year
179 set(UCAL_EXTENDED_YEAR, year - kDangiRelatedYearDiff);
180 }
181
getSetting(UErrorCode & status) const182 ChineseCalendar::Setting DangiCalendar::getSetting(UErrorCode& status) const {
183 return { DANGI_EPOCH_YEAR,
184 getAstronomerTimeZone(status),
185 &gWinterSolsticeCache, &gNewYearCache
186 };
187 }
188
189 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(DangiCalendar)
190
191 U_NAMESPACE_END
192
193 #endif
194
195