/*
* Copyright (C) 2004, 2006 Apple Computer, Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#import "config.h"
#import "TextBoundaries.h"
#import <Foundation/Foundation.h>
#import <unicode/uchar.h>
#import <unicode/ustring.h>
#import <unicode/utypes.h>
#import <unicode/ubrk.h>
namespace WebCore {
static bool isSkipCharacter(UChar c)
{
return c == 0xA0 ||
c == '\n' ||
c == '.' ||
c == ',' ||
c == '!' ||
c == '?' ||
c == ';' ||
c == ':' ||
u_isspace(c);
}
static bool isWhitespaceCharacter(UChar c)
{
return c == 0xA0 ||
c == '\n' ||
u_isspace(c);
}
static bool isWordDelimitingCharacter(UChar c)
{
CFCharacterSetRef set = CFCharacterSetGetPredefined(kCFCharacterSetAlphaNumeric);
return !CFCharacterSetIsCharacterMember(set, c) && c != '\'' && c != '&';
}
void findWordBoundary(const UChar* chars, int len, int position, int* start, int* end)
{
int startPos = position;
if (startPos > 0 && isWordDelimitingCharacter(chars[startPos-1]))
startPos--;
while (startPos > 0 && !isWordDelimitingCharacter(chars[startPos-1]))
startPos--;
int endPos = position;
while (endPos < len && !isWordDelimitingCharacter(chars[endPos]))
endPos++;
*start = startPos;
*end = endPos;
}
int findNextWordFromIndex(const UChar* chars, int len, int position, bool forward)
{
int pos = position;
UErrorCode status = U_ZERO_ERROR;
UBreakIterator *boundary = ubrk_open(UBRK_WORD, currentTextBreakLocaleID(), const_cast<unichar *>(reinterpret_cast<const unichar *>(chars)), len, &status);
if (boundary && U_SUCCESS(status)) {
if (forward) {
do {
pos = ubrk_following(boundary, pos);
if (pos == UBRK_DONE) {
pos = len;
}
} while (pos <= len && (pos == 0 || !isSkipCharacter(chars[pos-1])) && isSkipCharacter(chars[pos]));
}
else {
do {
pos = ubrk_preceding(boundary, pos);
if (pos == UBRK_DONE) {
pos = 0;
}
} while (pos > 0 && isSkipCharacter(chars[pos]) && !isWhitespaceCharacter(chars[pos-1]));
}
ubrk_close(boundary);
}
return pos;
}
// This code was swiped from the CarbonCore UnicodeUtilities. One change from that is to use the empty
// string instead of the "old locale model" as the ultimate fallback. This change is per the UnicodeUtilities
// engineer.
//
// NOTE: this abviously could be fairly expensive to do. If it turns out to be a bottleneck, it might
// help to instead put a call in the iteratory initializer to set the current text break locale. Unfortunately,
// we can not cache it across calls to our API since the result can change without our knowing (AFAIK
// there are no notifiers for AppleTextBreakLocale and/or AppleLanguages changes).
char* currentTextBreakLocaleID()
{
const int localeStringLength = 32;
static char localeStringBuffer[localeStringLength] = { 0 };
char* localeString = &localeStringBuffer[0];
// Empty string means "root locale", which what we use if we can't use a pref.
// We get the parts string from AppleTextBreakLocale pref.
// If that fails then look for the first language in the AppleLanguages pref.
CFStringRef prefLocaleStr = (CFStringRef)CFPreferencesCopyValue(CFSTR("AppleTextBreakLocale"),
kCFPreferencesAnyApplication, kCFPreferencesCurrentUser, kCFPreferencesAnyHost);
if (!prefLocaleStr) {
CFArrayRef appleLangArr = (CFArrayRef)CFPreferencesCopyValue(CFSTR("AppleLanguages"),
kCFPreferencesAnyApplication, kCFPreferencesCurrentUser, kCFPreferencesAnyHost);
if (appleLangArr) {
// Take the topmost language. Retain so that we can blindly release later.
prefLocaleStr = (CFStringRef)CFArrayGetValueAtIndex(appleLangArr, 0);
if (prefLocaleStr)
CFRetain(prefLocaleStr);
CFRelease(appleLangArr);
}
}
if (prefLocaleStr) {
// Canonicalize pref string in case it is not in the canonical format. This call is only available on Tiger and newer.
CFStringRef canonLocaleCFStr = CFLocaleCreateCanonicalLanguageIdentifierFromString(kCFAllocatorDefault, prefLocaleStr);
if (canonLocaleCFStr) {
CFStringGetCString(canonLocaleCFStr, localeString, localeStringLength, kCFStringEncodingASCII);
CFRelease(canonLocaleCFStr);
}
CFRelease(prefLocaleStr);
}
return localeString;
}
void findSentenceBoundary(const UChar* chars, int len, int position, int* start, int* end)
{
int startPos = 0;
int endPos = 0;
UErrorCode status = U_ZERO_ERROR;
UBreakIterator* boundary = ubrk_open(UBRK_SENTENCE, currentTextBreakLocaleID(), chars, len, &status);
if (boundary && U_SUCCESS(status)) {
startPos = ubrk_preceding(boundary, position);
if (startPos == UBRK_DONE) {
startPos = 0;
}
endPos = ubrk_following(boundary, startPos);
if (endPos == UBRK_DONE)
endPos = len;
ubrk_close(boundary);
}
*start = startPos;
*end = endPos;
}
int findNextSentenceFromIndex(const UChar* chars, int len, int position, bool forward)
{
int pos = 0;
UErrorCode status = U_ZERO_ERROR;
UBreakIterator* boundary = ubrk_open(UBRK_SENTENCE, currentTextBreakLocaleID(), chars, len, &status);
if (boundary && U_SUCCESS(status)) {
if (forward) {
pos = ubrk_following(boundary, position);
if (pos == UBRK_DONE)
pos = len;
} else {
pos = ubrk_preceding(boundary, position);
if (pos == UBRK_DONE)
pos = 0;
}
ubrk_close(boundary);
}
return pos;
}
}