scuffed-code/icu4c/source/i18n/strrepl.cpp

330 lines
11 KiB
C++

// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
**********************************************************************
* Copyright (c) 2002-2012, International Business Machines Corporation
* and others. All Rights Reserved.
**********************************************************************
* Date Name Description
* 01/21/2002 aliu Creation.
**********************************************************************
*/
#include "unicode/utypes.h"
#if !UCONFIG_NO_TRANSLITERATION
#include "unicode/uniset.h"
#include "unicode/utf16.h"
#include "strrepl.h"
#include "rbt_data.h"
#include "util.h"
U_NAMESPACE_BEGIN
UnicodeReplacer::~UnicodeReplacer() {}
UOBJECT_DEFINE_RTTI_IMPLEMENTATION(StringReplacer)
/**
* Construct a StringReplacer that sets the emits the given output
* text and sets the cursor to the given position.
* @param theOutput text that will replace input text when the
* replace() method is called. May contain stand-in characters
* that represent nested replacers.
* @param theCursorPos cursor position that will be returned by
* the replace() method
* @param theData transliterator context object that translates
* stand-in characters to UnicodeReplacer objects
*/
StringReplacer::StringReplacer(const UnicodeString& theOutput,
int32_t theCursorPos,
const TransliterationRuleData* theData) {
output = theOutput;
cursorPos = theCursorPos;
hasCursor = TRUE;
data = theData;
isComplex = TRUE;
}
/**
* Construct a StringReplacer that sets the emits the given output
* text and does not modify the cursor.
* @param theOutput text that will replace input text when the
* replace() method is called. May contain stand-in characters
* that represent nested replacers.
* @param theData transliterator context object that translates
* stand-in characters to UnicodeReplacer objects
*/
StringReplacer::StringReplacer(const UnicodeString& theOutput,
const TransliterationRuleData* theData) {
output = theOutput;
cursorPos = 0;
hasCursor = FALSE;
data = theData;
isComplex = TRUE;
}
/**
* Copy constructor.
*/
StringReplacer::StringReplacer(const StringReplacer& other) :
UnicodeFunctor(other),
UnicodeReplacer(other)
{
output = other.output;
cursorPos = other.cursorPos;
hasCursor = other.hasCursor;
data = other.data;
isComplex = other.isComplex;
}
/**
* Destructor
*/
StringReplacer::~StringReplacer() {
}
/**
* Implement UnicodeFunctor
*/
StringReplacer* StringReplacer::clone() const {
return new StringReplacer(*this);
}
/**
* Implement UnicodeFunctor
*/
UnicodeReplacer* StringReplacer::toReplacer() const {
return const_cast<StringReplacer *>(this);
}
/**
* UnicodeReplacer API
*/
int32_t StringReplacer::replace(Replaceable& text,
int32_t start,
int32_t limit,
int32_t& cursor) {
int32_t outLen;
int32_t newStart = 0;
// NOTE: It should be possible to _always_ run the complex
// processing code; just slower. If not, then there is a bug
// in the complex processing code.
// Simple (no nested replacers) Processing Code :
if (!isComplex) {
text.handleReplaceBetween(start, limit, output);
outLen = output.length();
// Setup default cursor position (for cursorPos within output)
newStart = cursorPos;
}
// Complex (nested replacers) Processing Code :
else {
/* When there are segments to be copied, use the Replaceable.copy()
* API in order to retain out-of-band data. Copy everything to the
* end of the string, then copy them back over the key. This preserves
* the integrity of indices into the key and surrounding context while
* generating the output text.
*/
UnicodeString buf;
int32_t oOutput; // offset into 'output'
isComplex = FALSE;
// The temporary buffer starts at tempStart, and extends
// to destLimit. The start of the buffer has a single
// character from before the key. This provides style
// data when addition characters are filled into the
// temporary buffer. If there is nothing to the left, use
// the non-character U+FFFF, which Replaceable subclasses
// should treat specially as a "no-style character."
// destStart points to the point after the style context
// character, so it is tempStart+1 or tempStart+2.
int32_t tempStart = text.length(); // start of temp buffer
int32_t destStart = tempStart; // copy new text to here
if (start > 0) {
int32_t len = U16_LENGTH(text.char32At(start-1));
text.copy(start-len, start, tempStart);
destStart += len;
} else {
UnicodeString str((UChar) 0xFFFF);
text.handleReplaceBetween(tempStart, tempStart, str);
destStart++;
}
int32_t destLimit = destStart;
for (oOutput=0; oOutput<output.length(); ) {
if (oOutput == cursorPos) {
// Record the position of the cursor
newStart = destLimit - destStart; // relative to start
}
UChar32 c = output.char32At(oOutput);
UnicodeReplacer* r = data->lookupReplacer(c);
if (r == NULL) {
// Accumulate straight (non-segment) text.
buf.append(c);
} else {
isComplex = TRUE;
// Insert any accumulated straight text.
if (buf.length() > 0) {
text.handleReplaceBetween(destLimit, destLimit, buf);
destLimit += buf.length();
buf.truncate(0);
}
// Delegate output generation to replacer object
int32_t len = r->replace(text, destLimit, destLimit, cursor);
destLimit += len;
}
oOutput += U16_LENGTH(c);
}
// Insert any accumulated straight text.
if (buf.length() > 0) {
text.handleReplaceBetween(destLimit, destLimit, buf);
destLimit += buf.length();
}
if (oOutput == cursorPos) {
// Record the position of the cursor
newStart = destLimit - destStart; // relative to start
}
outLen = destLimit - destStart;
// Copy new text to start, and delete it
text.copy(destStart, destLimit, start);
text.handleReplaceBetween(tempStart + outLen, destLimit + outLen, UnicodeString());
// Delete the old text (the key)
text.handleReplaceBetween(start + outLen, limit + outLen, UnicodeString());
}
if (hasCursor) {
// Adjust the cursor for positions outside the key. These
// refer to code points rather than code units. If cursorPos
// is within the output string, then use newStart, which has
// already been set above.
if (cursorPos < 0) {
newStart = start;
int32_t n = cursorPos;
// Outside the output string, cursorPos counts code points
while (n < 0 && newStart > 0) {
newStart -= U16_LENGTH(text.char32At(newStart-1));
++n;
}
newStart += n;
} else if (cursorPos > output.length()) {
newStart = start + outLen;
int32_t n = cursorPos - output.length();
// Outside the output string, cursorPos counts code points
while (n > 0 && newStart < text.length()) {
newStart += U16_LENGTH(text.char32At(newStart));
--n;
}
newStart += n;
} else {
// Cursor is within output string. It has been set up above
// to be relative to start.
newStart += start;
}
cursor = newStart;
}
return outLen;
}
/**
* UnicodeReplacer API
*/
UnicodeString& StringReplacer::toReplacerPattern(UnicodeString& rule,
UBool escapeUnprintable) const {
rule.truncate(0);
UnicodeString quoteBuf;
int32_t cursor = cursorPos;
// Handle a cursor preceding the output
if (hasCursor && cursor < 0) {
while (cursor++ < 0) {
ICU_Utility::appendToRule(rule, (UChar)0x0040 /*@*/, TRUE, escapeUnprintable, quoteBuf);
}
// Fall through and append '|' below
}
for (int32_t i=0; i<output.length(); ++i) {
if (hasCursor && i == cursor) {
ICU_Utility::appendToRule(rule, (UChar)0x007C /*|*/, TRUE, escapeUnprintable, quoteBuf);
}
UChar c = output.charAt(i); // Ok to use 16-bits here
UnicodeReplacer* r = data->lookupReplacer(c);
if (r == NULL) {
ICU_Utility::appendToRule(rule, c, FALSE, escapeUnprintable, quoteBuf);
} else {
UnicodeString buf;
r->toReplacerPattern(buf, escapeUnprintable);
buf.insert(0, (UChar)0x20);
buf.append((UChar)0x20);
ICU_Utility::appendToRule(rule, buf,
TRUE, escapeUnprintable, quoteBuf);
}
}
// Handle a cursor after the output. Use > rather than >= because
// if cursor == output.length() it is at the end of the output,
// which is the default position, so we need not emit it.
if (hasCursor && cursor > output.length()) {
cursor -= output.length();
while (cursor-- > 0) {
ICU_Utility::appendToRule(rule, (UChar)0x0040 /*@*/, TRUE, escapeUnprintable, quoteBuf);
}
ICU_Utility::appendToRule(rule, (UChar)0x007C /*|*/, TRUE, escapeUnprintable, quoteBuf);
}
// Flush quoteBuf out to result
ICU_Utility::appendToRule(rule, -1,
TRUE, escapeUnprintable, quoteBuf);
return rule;
}
/**
* Implement UnicodeReplacer
*/
void StringReplacer::addReplacementSetTo(UnicodeSet& toUnionTo) const {
UChar32 ch;
for (int32_t i=0; i<output.length(); i+=U16_LENGTH(ch)) {
ch = output.char32At(i);
UnicodeReplacer* r = data->lookupReplacer(ch);
if (r == NULL) {
toUnionTo.add(ch);
} else {
r->addReplacementSetTo(toUnionTo);
}
}
}
/**
* UnicodeFunctor API
*/
void StringReplacer::setData(const TransliterationRuleData* d) {
data = d;
int32_t i = 0;
while (i<output.length()) {
UChar32 c = output.char32At(i);
UnicodeFunctor* f = data->lookup(c);
if (f != NULL) {
f->setData(data);
}
i += U16_LENGTH(c);
}
}
U_NAMESPACE_END
#endif /* #if !UCONFIG_NO_TRANSLITERATION */
//eof