1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4 *******************************************************************************
5 * Copyright (C) 2007-2013, International Business Machines Corporation and
6 * others. All Rights Reserved.
7 *******************************************************************************
8 */
9 #ifndef VTZONE_H
10 #define VTZONE_H
11 
12 #include "unicode/utypes.h"
13 
14 #if U_SHOW_CPLUSPLUS_API
15 
16 /**
17  * \file
18  * \brief C++ API: RFC2445 VTIMEZONE support
19  */
20 
21 #if !UCONFIG_NO_FORMATTING
22 
23 #include "unicode/basictz.h"
24 
25 U_NAMESPACE_BEGIN
26 
27 class VTZWriter;
28 class VTZReader;
29 class UVector;
30 
31 /**
32  * <code>VTimeZone</code> is a class implementing RFC2445 VTIMEZONE.  You can create a
33  * <code>VTimeZone</code> instance from a time zone ID supported by <code>TimeZone</code>.
34  * With the <code>VTimeZone</code> instance created from the ID, you can write out the rule
35  * in RFC2445 VTIMEZONE format.  Also, you can create a <code>VTimeZone</code> instance
36  * from RFC2445 VTIMEZONE data stream, which allows you to calculate time
37  * zone offset by the rules defined by the data. Or, you can create a
38  * <code>VTimeZone</code> from any other ICU <code>BasicTimeZone</code>.
39  * <br><br>
40  * Note: The consumer of this class reading or writing VTIMEZONE data is responsible to
41  * decode or encode Non-ASCII text.  Methods reading/writing VTIMEZONE data in this class
42  * do nothing with MIME encoding.
43  * @stable ICU 3.8
44  */
45 class U_I18N_API VTimeZone : public BasicTimeZone {
46 public:
47     /**
48      * Copy constructor.
49      * @param source    The <code>VTimeZone</code> object to be copied.
50      * @stable ICU 3.8
51      */
52     VTimeZone(const VTimeZone& source);
53 
54     /**
55      * Destructor.
56      * @stable ICU 3.8
57      */
58     virtual ~VTimeZone();
59 
60     /**
61      * Assignment operator.
62      * @param right The object to be copied.
63      * @stable ICU 3.8
64      */
65     VTimeZone& operator=(const VTimeZone& right);
66 
67     /**
68      * Return true if the given <code>TimeZone</code> objects are
69      * semantically equal. Objects of different subclasses are considered unequal.
70      * @param that  The object to be compared with.
71      * @return  true if the given <code>TimeZone</code> objects are
72       *semantically equal.
73      * @stable ICU 3.8
74      */
75     virtual UBool operator==(const TimeZone& that) const;
76 
77     /**
78      * Return true if the given <code>TimeZone</code> objects are
79      * semantically unequal. Objects of different subclasses are considered unequal.
80      * @param that  The object to be compared with.
81      * @return  true if the given <code>TimeZone</code> objects are
82      * semantically unequal.
83      * @stable ICU 3.8
84      */
85     virtual UBool operator!=(const TimeZone& that) const;
86 
87     /**
88      * Create a <code>VTimeZone</code> instance by the time zone ID.
89      * @param ID The time zone ID, such as America/New_York
90      * @return A <code>VTimeZone</code> object initialized by the time zone ID,
91      * or NULL when the ID is unknown.
92      * @stable ICU 3.8
93      */
94     static VTimeZone* createVTimeZoneByID(const UnicodeString& ID);
95 
96     /**
97      * Create a <code>VTimeZone</code> instance using a basic time zone.
98      * @param basicTZ The basic time zone instance
99      * @param status Output param to filled in with a success or an error.
100      * @return A <code>VTimeZone</code> object initialized by the basic time zone.
101      * @stable ICU 4.6
102      */
103     static VTimeZone* createVTimeZoneFromBasicTimeZone(const BasicTimeZone& basicTZ,
104                                                        UErrorCode &status);
105 
106     /**
107      * Create a <code>VTimeZone</code> instance by RFC2445 VTIMEZONE data
108      *
109      * @param vtzdata The string including VTIMEZONE data block
110      * @param status Output param to filled in with a success or an error.
111      * @return A <code>VTimeZone</code> initialized by the VTIMEZONE data or
112      * NULL if failed to load the rule from the VTIMEZONE data.
113      * @stable ICU 3.8
114      */
115     static VTimeZone* createVTimeZone(const UnicodeString& vtzdata, UErrorCode& status);
116 
117     /**
118      * Gets the RFC2445 TZURL property value.  When a <code>VTimeZone</code> instance was
119      * created from VTIMEZONE data, the initial value is set by the TZURL property value
120      * in the data.  Otherwise, the initial value is not set.
121      * @param url Receives the RFC2445 TZURL property value.
122      * @return true if TZURL attribute is available and value is set.
123      * @stable ICU 3.8
124      */
125     UBool getTZURL(UnicodeString& url) const;
126 
127     /**
128      * Sets the RFC2445 TZURL property value.
129      * @param url The TZURL property value.
130      * @stable ICU 3.8
131      */
132     void setTZURL(const UnicodeString& url);
133 
134     /**
135      * Gets the RFC2445 LAST-MODIFIED property value.  When a <code>VTimeZone</code> instance
136      * was created from VTIMEZONE data, the initial value is set by the LAST-MODIFIED property
137      * value in the data.  Otherwise, the initial value is not set.
138      * @param lastModified Receives the last modified date.
139      * @return true if lastModified attribute is available and value is set.
140      * @stable ICU 3.8
141      */
142     UBool getLastModified(UDate& lastModified) const;
143 
144     /**
145      * Sets the RFC2445 LAST-MODIFIED property value.
146      * @param lastModified The LAST-MODIFIED date.
147      * @stable ICU 3.8
148      */
149     void setLastModified(UDate lastModified);
150 
151     /**
152      * Writes RFC2445 VTIMEZONE data for this time zone
153      * @param result Output param to filled in with the VTIMEZONE data.
154      * @param status Output param to filled in with a success or an error.
155      * @stable ICU 3.8
156      */
157     void write(UnicodeString& result, UErrorCode& status) const;
158 
159     /**
160      * Writes RFC2445 VTIMEZONE data for this time zone applicalbe
161      * for dates after the specified start time.
162      * @param start The start date.
163      * @param result Output param to filled in with the VTIMEZONE data.
164      * @param status Output param to filled in with a success or an error.
165      * @stable ICU 3.8
166      */
167     void write(UDate start, UnicodeString& result, UErrorCode& status) const;
168 
169     /**
170      * Writes RFC2445 VTIMEZONE data applicalbe for the specified date.
171      * Some common iCalendar implementations can only handle a single time
172      * zone property or a pair of standard and daylight time properties using
173      * BYDAY rule with day of week (such as BYDAY=1SUN).  This method produce
174      * the VTIMEZONE data which can be handled these implementations.  The rules
175      * produced by this method can be used only for calculating time zone offset
176      * around the specified date.
177      * @param time The date used for rule extraction.
178      * @param result Output param to filled in with the VTIMEZONE data.
179      * @param status Output param to filled in with a success or an error.
180      * @stable ICU 3.8
181      */
182     void writeSimple(UDate time, UnicodeString& result, UErrorCode& status) const;
183 
184     /**
185      * Clones TimeZone objects polymorphically. Clients are responsible for deleting
186      * the TimeZone object cloned.
187      * @return   A new copy of this TimeZone object.
188      * @stable ICU 3.8
189      */
190     virtual VTimeZone* clone() const;
191 
192     /**
193      * Returns the TimeZone's adjusted GMT offset (i.e., the number of milliseconds to add
194      * to GMT to get local time in this time zone, taking daylight savings time into
195      * account) as of a particular reference date.  The reference date is used to determine
196      * whether daylight savings time is in effect and needs to be figured into the offset
197      * that is returned (in other words, what is the adjusted GMT offset in this time zone
198      * at this particular date and time?).  For the time zones produced by createTimeZone(),
199      * the reference data is specified according to the Gregorian calendar, and the date
200      * and time fields are local standard time.
201      *
202      * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload,
203      * which returns both the raw and the DST offset for a given time. This method
204      * is retained only for backward compatibility.
205      *
206      * @param era        The reference date's era
207      * @param year       The reference date's year
208      * @param month      The reference date's month (0-based; 0 is January)
209      * @param day        The reference date's day-in-month (1-based)
210      * @param dayOfWeek  The reference date's day-of-week (1-based; 1 is Sunday)
211      * @param millis     The reference date's milliseconds in day, local standard time
212      * @param status     Output param to filled in with a success or an error.
213      * @return           The offset in milliseconds to add to GMT to get local time.
214      * @stable ICU 3.8
215      */
216     virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
217                               uint8_t dayOfWeek, int32_t millis, UErrorCode& status) const;
218 
219     /**
220      * Gets the time zone offset, for current date, modified in case of
221      * daylight savings. This is the offset to add *to* UTC to get local time.
222      *
223      * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload,
224      * which returns both the raw and the DST offset for a given time. This method
225      * is retained only for backward compatibility.
226      *
227      * @param era        The reference date's era
228      * @param year       The reference date's year
229      * @param month      The reference date's month (0-based; 0 is January)
230      * @param day        The reference date's day-in-month (1-based)
231      * @param dayOfWeek  The reference date's day-of-week (1-based; 1 is Sunday)
232      * @param millis     The reference date's milliseconds in day, local standard time
233      * @param monthLength The length of the given month in days.
234      * @param status     Output param to filled in with a success or an error.
235      * @return           The offset in milliseconds to add to GMT to get local time.
236      * @stable ICU 3.8
237      */
238     virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
239                            uint8_t dayOfWeek, int32_t millis,
240                            int32_t monthLength, UErrorCode& status) const;
241 
242     /**
243      * Returns the time zone raw and GMT offset for the given moment
244      * in time.  Upon return, local-millis = GMT-millis + rawOffset +
245      * dstOffset.  All computations are performed in the proleptic
246      * Gregorian calendar.  The default implementation in the TimeZone
247      * class delegates to the 8-argument getOffset().
248      *
249      * @param date moment in time for which to return offsets, in
250      * units of milliseconds from January 1, 1970 0:00 GMT, either GMT
251      * time or local wall time, depending on `local'.
252      * @param local if true, `date' is local wall time; otherwise it
253      * is in GMT time.
254      * @param rawOffset output parameter to receive the raw offset, that
255      * is, the offset not including DST adjustments
256      * @param dstOffset output parameter to receive the DST offset,
257      * that is, the offset to be added to `rawOffset' to obtain the
258      * total offset between local and GMT time. If DST is not in
259      * effect, this value is zero; otherwise it is a positive value,
260      * typically one hour.
261      * @param ec input-output error code
262      * @stable ICU 3.8
263      */
264     virtual void getOffset(UDate date, UBool local, int32_t& rawOffset,
265                            int32_t& dstOffset, UErrorCode& ec) const;
266 
267     /**
268      * Sets the TimeZone's raw GMT offset (i.e., the number of milliseconds to add
269      * to GMT to get local time, before taking daylight savings time into account).
270      *
271      * @param offsetMillis  The new raw GMT offset for this time zone.
272      * @stable ICU 3.8
273      */
274     virtual void setRawOffset(int32_t offsetMillis);
275 
276     /**
277      * Returns the TimeZone's raw GMT offset (i.e., the number of milliseconds to add
278      * to GMT to get local time, before taking daylight savings time into account).
279      *
280      * @return   The TimeZone's raw GMT offset.
281      * @stable ICU 3.8
282      */
283     virtual int32_t getRawOffset(void) const;
284 
285     /**
286      * Queries if this time zone uses daylight savings time.
287      * @return true if this time zone uses daylight savings time,
288      * false, otherwise.
289      * @stable ICU 3.8
290      */
291     virtual UBool useDaylightTime(void) const;
292 
293 #ifndef U_FORCE_HIDE_DEPRECATED_API
294     /**
295      * Queries if the given date is in daylight savings time in
296      * this time zone.
297      * This method is wasteful since it creates a new GregorianCalendar and
298      * deletes it each time it is called. This is a deprecated method
299      * and provided only for Java compatibility.
300      *
301      * @param date the given UDate.
302      * @param status Output param filled in with success/error code.
303      * @return true if the given date is in daylight savings time,
304      * false, otherwise.
305      * @deprecated ICU 2.4. Use Calendar::inDaylightTime() instead.
306      */
307     virtual UBool inDaylightTime(UDate date, UErrorCode& status) const;
308 #endif  // U_FORCE_HIDE_DEPRECATED_API
309 
310     /**
311      * Returns true if this zone has the same rule and offset as another zone.
312      * That is, if this zone differs only in ID, if at all.
313      * @param other the <code>TimeZone</code> object to be compared with
314      * @return true if the given zone is the same as this one,
315      * with the possible exception of the ID
316      * @stable ICU 3.8
317      */
318     virtual UBool hasSameRules(const TimeZone& other) const;
319 
320     /**
321      * Gets the first time zone transition after the base time.
322      * @param base      The base time.
323      * @param inclusive Whether the base time is inclusive or not.
324      * @param result    Receives the first transition after the base time.
325      * @return  true if the transition is found.
326      * @stable ICU 3.8
327      */
328     virtual UBool getNextTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const;
329 
330     /**
331      * Gets the most recent time zone transition before the base time.
332      * @param base      The base time.
333      * @param inclusive Whether the base time is inclusive or not.
334      * @param result    Receives the most recent transition before the base time.
335      * @return  true if the transition is found.
336      * @stable ICU 3.8
337      */
338     virtual UBool getPreviousTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const;
339 
340     /**
341      * Returns the number of <code>TimeZoneRule</code>s which represents time transitions,
342      * for this time zone, that is, all <code>TimeZoneRule</code>s for this time zone except
343      * <code>InitialTimeZoneRule</code>.  The return value range is 0 or any positive value.
344      * @param status    Receives error status code.
345      * @return The number of <code>TimeZoneRule</code>s representing time transitions.
346      * @stable ICU 3.8
347      */
348     virtual int32_t countTransitionRules(UErrorCode& status) const;
349 
350     /**
351      * Gets the <code>InitialTimeZoneRule</code> and the set of <code>TimeZoneRule</code>
352      * which represent time transitions for this time zone.  On successful return,
353      * the argument initial points to non-NULL <code>InitialTimeZoneRule</code> and
354      * the array trsrules is filled with 0 or multiple <code>TimeZoneRule</code>
355      * instances up to the size specified by trscount.  The results are referencing the
356      * rule instance held by this time zone instance.  Therefore, after this time zone
357      * is destructed, they are no longer available.
358      * @param initial       Receives the initial timezone rule
359      * @param trsrules      Receives the timezone transition rules
360      * @param trscount      On input, specify the size of the array 'transitions' receiving
361      *                      the timezone transition rules.  On output, actual number of
362      *                      rules filled in the array will be set.
363      * @param status        Receives error status code.
364      * @stable ICU 3.8
365      */
366     virtual void getTimeZoneRules(const InitialTimeZoneRule*& initial,
367         const TimeZoneRule* trsrules[], int32_t& trscount, UErrorCode& status) const;
368 
369 private:
370     enum { DEFAULT_VTIMEZONE_LINES = 100 };
371 
372     /**
373      * Default constructor.
374      */
375     VTimeZone();
376     static VTimeZone* createVTimeZone(VTZReader* reader);
377     void write(VTZWriter& writer, UErrorCode& status) const;
378     void write(UDate start, VTZWriter& writer, UErrorCode& status) const;
379     void writeSimple(UDate time, VTZWriter& writer, UErrorCode& status) const;
380     void load(VTZReader& reader, UErrorCode& status);
381     void parse(UErrorCode& status);
382 
383     void writeZone(VTZWriter& w, BasicTimeZone& basictz, UVector* customProps,
384         UErrorCode& status) const;
385 
386     void writeHeaders(VTZWriter& w, UErrorCode& status) const;
387     void writeFooter(VTZWriter& writer, UErrorCode& status) const;
388 
389     void writeZonePropsByTime(VTZWriter& writer, UBool isDst, const UnicodeString& zonename,
390                               int32_t fromOffset, int32_t toOffset, UDate time, UBool withRDATE,
391                               UErrorCode& status) const;
392     void writeZonePropsByDOM(VTZWriter& writer, UBool isDst, const UnicodeString& zonename,
393                              int32_t fromOffset, int32_t toOffset,
394                              int32_t month, int32_t dayOfMonth, UDate startTime, UDate untilTime,
395                              UErrorCode& status) const;
396     void writeZonePropsByDOW(VTZWriter& writer, UBool isDst, const UnicodeString& zonename,
397                              int32_t fromOffset, int32_t toOffset,
398                              int32_t month, int32_t weekInMonth, int32_t dayOfWeek,
399                              UDate startTime, UDate untilTime, UErrorCode& status) const;
400     void writeZonePropsByDOW_GEQ_DOM(VTZWriter& writer, UBool isDst, const UnicodeString& zonename,
401                                      int32_t fromOffset, int32_t toOffset,
402                                      int32_t month, int32_t dayOfMonth, int32_t dayOfWeek,
403                                      UDate startTime, UDate untilTime, UErrorCode& status) const;
404     void writeZonePropsByDOW_GEQ_DOM_sub(VTZWriter& writer, int32_t month, int32_t dayOfMonth,
405                                          int32_t dayOfWeek, int32_t numDays,
406                                          UDate untilTime, int32_t fromOffset, UErrorCode& status) const;
407     void writeZonePropsByDOW_LEQ_DOM(VTZWriter& writer, UBool isDst, const UnicodeString& zonename,
408                                      int32_t fromOffset, int32_t toOffset,
409                                      int32_t month, int32_t dayOfMonth, int32_t dayOfWeek,
410                                      UDate startTime, UDate untilTime, UErrorCode& status) const;
411     void writeFinalRule(VTZWriter& writer, UBool isDst, const AnnualTimeZoneRule* rule,
412                         int32_t fromRawOffset, int32_t fromDSTSavings,
413                         UDate startTime, UErrorCode& status) const;
414 
415     void beginZoneProps(VTZWriter& writer, UBool isDst, const UnicodeString& zonename,
416                         int32_t fromOffset, int32_t toOffset, UDate startTime, UErrorCode& status) const;
417     void endZoneProps(VTZWriter& writer, UBool isDst, UErrorCode& status) const;
418     void beginRRULE(VTZWriter& writer, int32_t month, UErrorCode& status) const;
419     void appendUNTIL(VTZWriter& writer, const UnicodeString& until, UErrorCode& status) const;
420 
421     BasicTimeZone   *tz;
422     UVector         *vtzlines;
423     UnicodeString   tzurl;
424     UDate           lastmod;
425     UnicodeString   olsonzid;
426     UnicodeString   icutzver;
427 
428 public:
429     /**
430      * Return the class ID for this class. This is useful only for comparing to
431      * a return value from getDynamicClassID(). For example:
432      * <pre>
433      * .   Base* polymorphic_pointer = createPolymorphicObject();
434      * .   if (polymorphic_pointer->getDynamicClassID() ==
435      * .       erived::getStaticClassID()) ...
436      * </pre>
437      * @return          The class ID for all objects of this class.
438      * @stable ICU 3.8
439      */
440     static UClassID U_EXPORT2 getStaticClassID(void);
441 
442     /**
443      * Returns a unique class ID POLYMORPHICALLY. Pure virtual override. This
444      * method is to implement a simple version of RTTI, since not all C++
445      * compilers support genuine RTTI. Polymorphic operator==() and clone()
446      * methods call this method.
447      *
448      * @return          The class ID for this object. All objects of a
449      *                  given class have the same class ID.  Objects of
450      *                  other classes have different class IDs.
451      * @stable ICU 3.8
452      */
453     virtual UClassID getDynamicClassID(void) const;
454 };
455 
456 U_NAMESPACE_END
457 
458 #endif /* #if !UCONFIG_NO_FORMATTING */
459 
460 #endif /* U_SHOW_CPLUSPLUS_API */
461 
462 #endif // VTZONE_H
463 //eof
464