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1 /*
2 **********************************************************************
3 * Copyright (C) 2001-2011, International Business Machines
4 * Corporation and others. All Rights Reserved.
5 **********************************************************************
6 * Date Name Description
7 * 05/24/01 aliu Creation.
8 **********************************************************************
9 */
10
11 #include "unicode/utypes.h"
12
13 #if !UCONFIG_NO_TRANSLITERATION
14
15 #include "unicode/uchar.h"
16 #include "unicode/uniset.h"
17 #include "unicode/ustring.h"
18 #include "unicode/utf16.h"
19 #include "titletrn.h"
20 #include "umutex.h"
21 #include "ucase.h"
22 #include "cpputils.h"
23
24 U_NAMESPACE_BEGIN
25
26 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(TitlecaseTransliterator)
27
28 TitlecaseTransliterator::TitlecaseTransliterator() :
29 CaseMapTransliterator(UNICODE_STRING("Any-Title", 9), NULL)
30 {
31 // Need to look back 2 characters in the case of "can't"
32 setMaximumContextLength(2);
33 }
34
35 /**
36 * Destructor.
37 */
38 TitlecaseTransliterator::~TitlecaseTransliterator() {
39 }
40
41 /**
42 * Copy constructor.
43 */
44 TitlecaseTransliterator::TitlecaseTransliterator(const TitlecaseTransliterator& o) :
45 CaseMapTransliterator(o)
46 {
47 }
48
49 /**
50 * Assignment operator.
51 */
52 /*TitlecaseTransliterator& TitlecaseTransliterator::operator=(
53 const TitlecaseTransliterator& o) {
54 CaseMapTransliterator::operator=(o);
55 return *this;
56 }*/
57
58 /**
59 * Transliterator API.
60 */
61 Transliterator* TitlecaseTransliterator::clone(void) const {
62 return new TitlecaseTransliterator(*this);
63 }
64
65 /**
66 * Implements {@link Transliterator#handleTransliterate}.
67 */
68 void TitlecaseTransliterator::handleTransliterate(
69 Replaceable& text, UTransPosition& offsets,
70 UBool isIncremental) const
71 {
72 // TODO reimplement, see ustrcase.c
73 // using a real word break iterator
74 // instead of just looking for a transition between cased and uncased characters
75 // call CaseMapTransliterator::handleTransliterate() for lowercasing? (set fMap)
76 // needs to take isIncremental into account because case mappings are context-sensitive
77 // also detect when lowercasing function did not finish because of context
78
79 if (offsets.start >= offsets.limit) {
80 return;
81 }
82
83 // case type: >0 cased (UCASE_LOWER etc.) ==0 uncased <0 case-ignorable
84 int32_t type;
85
86 // Our mode; we are either converting letter toTitle or
87 // toLower.
88 UBool doTitle = TRUE;
89
90 // Determine if there is a preceding context of cased case-ignorable*,
91 // in which case we want to start in toLower mode. If the
92 // prior context is anything else (including empty) then start
93 // in toTitle mode.
94 UChar32 c;
95 int32_t start;
96 for (start = offsets.start - 1; start >= offsets.contextStart; start -= U16_LENGTH(c)) {
97 c = text.char32At(start);
98 type=ucase_getTypeOrIgnorable(fCsp, c);
99 if(type>0) { // cased
100 doTitle=FALSE;
101 break;
102 } else if(type==0) { // uncased but not ignorable
103 break;
104 }
105 // else (type<0) case-ignorable: continue
106 }
107
108 // Convert things after a cased character toLower; things
109 // after an uncased, non-case-ignorable character toTitle. Case-ignorable
110 // characters are copied directly and do not change the mode.
111 UCaseContext csc;
112 uprv_memset(&csc, 0, sizeof(csc));
113 csc.p = &text;
114 csc.start = offsets.contextStart;
115 csc.limit = offsets.contextLimit;
116
117 UnicodeString tmp;
118 const UChar *s;
119 int32_t textPos, delta, result, locCache=0;
120
121 for(textPos=offsets.start; textPos<offsets.limit;) {
122 csc.cpStart=textPos;
123 c=text.char32At(textPos);
124 csc.cpLimit=textPos+=U16_LENGTH(c);
125
126 type=ucase_getTypeOrIgnorable(fCsp, c);
127 if(type>=0) { // not case-ignorable
128 if(doTitle) {
129 result=ucase_toFullTitle(fCsp, c, utrans_rep_caseContextIterator, &csc, &s, "", &locCache);
130 } else {
131 result=ucase_toFullLower(fCsp, c, utrans_rep_caseContextIterator, &csc, &s, "", &locCache);
132 }
133 doTitle = (UBool)(type==0); // doTitle=isUncased
134
135 if(csc.b1 && isIncremental) {
136 // fMap() tried to look beyond the context limit
137 // wait for more input
138 offsets.start=csc.cpStart;
139 return;
140 }
141
142 if(result>=0) {
143 // replace the current code point with its full case mapping result
144 // see UCASE_MAX_STRING_LENGTH
145 if(result<=UCASE_MAX_STRING_LENGTH) {
146 // string s[result]
147 tmp.setTo(FALSE, s, result);
148 delta=result-U16_LENGTH(c);
149 } else {
150 // single code point
151 tmp.setTo(result);
152 delta=tmp.length()-U16_LENGTH(c);
153 }
154 text.handleReplaceBetween(csc.cpStart, textPos, tmp);
155 if(delta!=0) {
156 textPos+=delta;
157 csc.limit=offsets.contextLimit+=delta;
158 offsets.limit+=delta;
159 }
160 }
161 }
162 }
163 offsets.start=textPos;
164 }
165
166 U_NAMESPACE_END
167
168 #endif /* #if !UCONFIG_NO_TRANSLITERATION */