1// © 2018 and later: Unicode, Inc. and others.
2// License & terms of use: http://www.unicode.org/copyright.html
3
4#include "unicode/utypes.h"
5
6#if !UCONFIG_NO_FORMATTING
7
8// Allow implicit conversion from char16_t* to UnicodeString for this file:
9// Helpful in toString methods and elsewhere.
10#define UNISTR_FROM_STRING_EXPLICIT
11
12#include "numparse_types.h"
13#include "string_segment.h"
14#include "putilimp.h"
15#include "unicode/utf16.h"
16#include "unicode/uniset.h"
17
18U_NAMESPACE_BEGIN
19
20
21StringSegment::StringSegment(const UnicodeString& str, bool ignoreCase)
22 : fStr(str), fStart(0), fEnd(str.length()),
23 fFoldCase(ignoreCase) {}
24
25int32_t StringSegment::getOffset() const {
26 return fStart;
27}
28
29void StringSegment::setOffset(int32_t start) {
30 fStart = start;
31}
32
33void StringSegment::adjustOffset(int32_t delta) {
34 fStart += delta;
35}
36
37void StringSegment::adjustOffsetByCodePoint() {
38 fStart += U16_LENGTH(getCodePoint());
39}
40
41void StringSegment::setLength(int32_t length) {
42 fEnd = fStart + length;
43}
44
45void StringSegment::resetLength() {
46 fEnd = fStr.length();
47}
48
49int32_t StringSegment::length() const {
50 return fEnd - fStart;
51}
52
53char16_t StringSegment::charAt(int32_t index) const {
54 return fStr.charAt(index + fStart);
55}
56
57UChar32 StringSegment::codePointAt(int32_t index) const {
58 return fStr.char32At(index + fStart);
59}
60
61UnicodeString StringSegment::toUnicodeString() const {
62 return UnicodeString(fStr.getBuffer() + fStart, fEnd - fStart);
63}
64
65const UnicodeString StringSegment::toTempUnicodeString() const {
66 // Use the readonly-aliasing constructor for efficiency.
67 return UnicodeString(FALSE, fStr.getBuffer() + fStart, fEnd - fStart);
68}
69
70UChar32 StringSegment::getCodePoint() const {
71 char16_t lead = fStr.charAt(fStart);
72 if (U16_IS_LEAD(lead) && fStart + 1 < fEnd) {
73 return fStr.char32At(fStart);
74 } else if (U16_IS_SURROGATE(lead)) {
75 return -1;
76 } else {
77 return lead;
78 }
79}
80
81bool StringSegment::startsWith(UChar32 otherCp) const {
82 return codePointsEqual(getCodePoint(), otherCp, fFoldCase);
83}
84
85bool StringSegment::startsWith(const UnicodeSet& uniset) const {
86 // TODO: Move UnicodeSet case-folding logic here.
87 // TODO: Handle string matches here instead of separately.
88 UChar32 cp = getCodePoint();
89 if (cp == -1) {
90 return false;
91 }
92 return uniset.contains(cp);
93}
94
95bool StringSegment::startsWith(const UnicodeString& other) const {
96 if (other.isBogus() || other.length() == 0 || length() == 0) {
97 return false;
98 }
99 int cp1 = getCodePoint();
100 int cp2 = other.char32At(0);
101 return codePointsEqual(cp1, cp2, fFoldCase);
102}
103
104int32_t StringSegment::getCommonPrefixLength(const UnicodeString& other) {
105 return getPrefixLengthInternal(other, fFoldCase);
106}
107
108int32_t StringSegment::getCaseSensitivePrefixLength(const UnicodeString& other) {
109 return getPrefixLengthInternal(other, false);
110}
111
112int32_t StringSegment::getPrefixLengthInternal(const UnicodeString& other, bool foldCase) {
113 U_ASSERT(other.length() > 0);
114 int32_t offset = 0;
115 for (; offset < uprv_min(length(), other.length());) {
116 // TODO: case-fold code points, not chars
117 char16_t c1 = charAt(offset);
118 char16_t c2 = other.charAt(offset);
119 if (!codePointsEqual(c1, c2, foldCase)) {
120 break;
121 }
122 offset++;
123 }
124 return offset;
125}
126
127bool StringSegment::codePointsEqual(UChar32 cp1, UChar32 cp2, bool foldCase) {
128 if (cp1 == cp2) {
129 return true;
130 }
131 if (!foldCase) {
132 return false;
133 }
134 cp1 = u_foldCase(cp1, TRUE);
135 cp2 = u_foldCase(cp2, TRUE);
136 return cp1 == cp2;
137}
138
139bool StringSegment::operator==(const UnicodeString& other) const {
140 return toTempUnicodeString() == other;
141}
142
143
144U_NAMESPACE_END
145#endif /* #if !UCONFIG_NO_FORMATTING */
146