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 "gregoimp.h" // Math
19 #include "uassert.h"
20 #include "ucln_in.h"
21 #include "umutex.h"
22 #include "unicode/rbtz.h"
23 #include "unicode/tzrule.h"
24 
25 // --- The cache --
26 static icu::TimeZone *gDangiCalendarZoneAstroCalc = NULL;
27 static icu::UInitOnce gDangiCalendarInitOnce = U_INITONCE_INITIALIZER;
28 
29 /**
30  * The start year of the Korean traditional calendar (Dan-gi) is the inaugural
31  * year of Dan-gun (BC 2333).
32  */
33 static const int32_t DANGI_EPOCH_YEAR = -2332; // Gregorian year
34 
35 U_CDECL_BEGIN
calendar_dangi_cleanup(void)36 static UBool calendar_dangi_cleanup(void) {
37     if (gDangiCalendarZoneAstroCalc) {
38         delete gDangiCalendarZoneAstroCalc;
39         gDangiCalendarZoneAstroCalc = NULL;
40     }
41     gDangiCalendarInitOnce.reset();
42     return TRUE;
43 }
44 U_CDECL_END
45 
46 U_NAMESPACE_BEGIN
47 
48 // Implementation of the DangiCalendar class
49 
50 //-------------------------------------------------------------------------
51 // Constructors...
52 //-------------------------------------------------------------------------
53 
DangiCalendar(const Locale & aLocale,UErrorCode & success)54 DangiCalendar::DangiCalendar(const Locale& aLocale, UErrorCode& success)
55 :   ChineseCalendar(aLocale, DANGI_EPOCH_YEAR, getDangiCalZoneAstroCalc(), success)
56 {
57 }
58 
DangiCalendar(const DangiCalendar & other)59 DangiCalendar::DangiCalendar (const DangiCalendar& other)
60 : ChineseCalendar(other)
61 {
62 }
63 
~DangiCalendar()64 DangiCalendar::~DangiCalendar()
65 {
66 }
67 
68 DangiCalendar*
clone() const69 DangiCalendar::clone() const
70 {
71     return new DangiCalendar(*this);
72 }
73 
getType() const74 const char *DangiCalendar::getType() const {
75     return "dangi";
76 }
77 
78 /**
79  * The time zone used for performing astronomical computations for
80  * Dangi calendar. In Korea various timezones have been used historically
81  * (cf. http://www.math.snu.ac.kr/~kye/others/lunar.html):
82  *
83  *            - 1908/04/01: GMT+8
84  * 1908/04/01 - 1911/12/31: GMT+8.5
85  * 1912/01/01 - 1954/03/20: GMT+9
86  * 1954/03/21 - 1961/08/09: GMT+8.5
87  * 1961/08/10 -           : GMT+9
88  *
89  * Note that, in 1908-1911, the government did not apply the timezone change
90  * but used GMT+8. In addition, 1954-1961's timezone change does not affect
91  * the lunar date calculation. Therefore, the following simpler rule works:
92  *
93  * -1911: GMT+8
94  * 1912-: GMT+9
95  *
96  * Unfortunately, our astronomer's approximation doesn't agree with the
97  * references (http://www.math.snu.ac.kr/~kye/others/lunar.html and
98  * http://astro.kasi.re.kr/Life/ConvertSolarLunarForm.aspx?MenuID=115)
99  * in 1897/7/30. So the following ad hoc fix is used here:
100  *
101  *     -1896: GMT+8
102  *      1897: GMT+7
103  * 1898-1911: GMT+8
104  * 1912-    : GMT+9
105  */
initDangiCalZoneAstroCalc(void)106 static void U_CALLCONV initDangiCalZoneAstroCalc(void) {
107     U_ASSERT(gDangiCalendarZoneAstroCalc == NULL);
108     const UDate millis1897[] = { (UDate)((1897 - 1970) * 365 * kOneDay) }; // some days of error is not a problem here
109     const UDate millis1898[] = { (UDate)((1898 - 1970) * 365 * kOneDay) }; // some days of error is not a problem here
110     const UDate millis1912[] = { (UDate)((1912 - 1970) * 365 * kOneDay) }; // this doesn't create an issue for 1911/12/20
111     InitialTimeZoneRule* initialTimeZone = new InitialTimeZoneRule(UNICODE_STRING_SIMPLE("GMT+8"), 8*kOneHour, 0);
112     TimeZoneRule* rule1897 = new TimeArrayTimeZoneRule(UNICODE_STRING_SIMPLE("Korean 1897"), 7*kOneHour, 0, millis1897, 1, DateTimeRule::STANDARD_TIME);
113     TimeZoneRule* rule1898to1911 = new TimeArrayTimeZoneRule(UNICODE_STRING_SIMPLE("Korean 1898-1911"), 8*kOneHour, 0, millis1898, 1, DateTimeRule::STANDARD_TIME);
114     TimeZoneRule* ruleFrom1912 = new TimeArrayTimeZoneRule(UNICODE_STRING_SIMPLE("Korean 1912-"), 9*kOneHour, 0, millis1912, 1, DateTimeRule::STANDARD_TIME);
115     UErrorCode status = U_ZERO_ERROR;
116     RuleBasedTimeZone* dangiCalZoneAstroCalc = new RuleBasedTimeZone(UNICODE_STRING_SIMPLE("KOREA_ZONE"), initialTimeZone); // adopts initialTimeZone
117     dangiCalZoneAstroCalc->addTransitionRule(rule1897, status); // adopts rule1897
118     dangiCalZoneAstroCalc->addTransitionRule(rule1898to1911, status);
119     dangiCalZoneAstroCalc->addTransitionRule(ruleFrom1912, status);
120     dangiCalZoneAstroCalc->complete(status);
121     if (U_SUCCESS(status)) {
122         gDangiCalendarZoneAstroCalc = dangiCalZoneAstroCalc;
123     } else {
124         delete dangiCalZoneAstroCalc;
125         gDangiCalendarZoneAstroCalc = NULL;
126     }
127     ucln_i18n_registerCleanup(UCLN_I18N_DANGI_CALENDAR, calendar_dangi_cleanup);
128 }
129 
getDangiCalZoneAstroCalc(void) const130 const TimeZone* DangiCalendar::getDangiCalZoneAstroCalc(void) const {
131     umtx_initOnce(gDangiCalendarInitOnce, &initDangiCalZoneAstroCalc);
132     return gDangiCalendarZoneAstroCalc;
133 }
134 
135 
136 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(DangiCalendar)
137 
138 U_NAMESPACE_END
139 
140 #endif
141 
142