gecko-dev/layout/generic/nsTextTransformer.cpp
1999-01-05 23:02:27 +00:00

388 lines
10 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/NPL/
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
* the License for the specific language governing rights and limitations
* under the License.
*
* The Original Code is Mozilla Communicator client code.
*
* The Initial Developer of the Original Code is Netscape Communications
* Corporation. Portions created by Netscape are Copyright (C) 1998
* Netscape Communications Corporation. All Rights Reserved.
*/
#include "nsTextTransformer.h"
#include "nsIContent.h"
#include "nsIFrame.h"
#include "nsIStyleContext.h"
#include "nsITextContent.h"
#include "nsStyleConsts.h"
// XXX put a copy in nsHTMLIIDs
static NS_DEFINE_IID(kITextContentIID, NS_ITEXT_CONTENT_IID);
// XXX I'm sure there are other special characters
#define CH_NBSP 160
#define MAX_UNIBYTE 127
nsTextTransformer::nsTextTransformer(PRUnichar* aBuffer, PRInt32 aBufLen)
: mAutoBuffer(aBuffer),
mBuffer(aBuffer),
mBufferLength(aBufLen < 0 ? 0 : aBufLen),
mHasMultibyte(PR_FALSE)
{
}
nsTextTransformer::~nsTextTransformer()
{
if (mBuffer != mAutoBuffer) {
delete [] mBuffer;
}
}
nsresult
nsTextTransformer::Init(/*nsTextRun& aTextRun, XXX*/
nsIFrame* aFrame,
PRInt32 aStartingOffset)
{
// Make sure we have *some* space in case arguments to the ctor were
// bizzare.
if (mBufferLength < 100) {
if (!GrowBuffer()) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
// Get the frames text content
nsIContent* content;
aFrame->GetContent(content);
nsITextContent* tc;
if (NS_OK != content->QueryInterface(kITextContentIID, (void**) &tc)) {
NS_RELEASE(content);
return NS_OK;
}
tc->GetText(mFrags, mNumFrags);
NS_RELEASE(tc);
NS_RELEASE(content);
mStartingOffset = aStartingOffset;
mOffset = mStartingOffset;
// Compute the total length of the text content.
PRInt32 sum = 0;
PRInt32 n = mNumFrags;
const nsTextFragment* frag = mFrags;
for (; --n >= 0; frag++) {
sum += frag->GetLength();
}
mContentLength = sum;
// Set current fragment and current fragment offset
mCurrentFrag = mFrags;
mCurrentFragOffset = 0;
PRInt32 offset = 0;
n = mNumFrags;
for (frag = mFrags; --n >= 0; frag++) {
if (aStartingOffset < offset + frag->GetLength()) {
mCurrentFrag = frag;
mCurrentFragOffset = aStartingOffset - offset;
break;
}
offset += frag->GetLength();
}
// Get the frames style and choose a transform proc
const nsStyleText* styleText;
aFrame->GetStyleData(eStyleStruct_Text, (const nsStyleStruct*&) styleText);
mWhiteSpace = styleText->mWhiteSpace;
mTextTransform = styleText->mTextTransform;
return NS_OK;
}
PRBool
nsTextTransformer::GrowBuffer()
{
PRInt32 newLen = mBufferLength * 2;
if (newLen <= 100) {
newLen = 100;
}
PRUnichar* newBuffer = new PRUnichar[newLen];
if (nsnull == newBuffer) {
return PR_FALSE;
}
if (0 != mBufferLength) {
nsCRT::memcpy(newBuffer, mBuffer, sizeof(PRUnichar) * mBufferLength);
if (mBuffer != mAutoBuffer) {
delete [] mBuffer;
}
}
mBuffer = newBuffer;
mBufferLength = newLen;
return PR_TRUE;
}
PRUnichar*
nsTextTransformer::GetNextWord(PRBool aInWord,
PRInt32& aWordLenResult,
PRInt32& aContentLenResult,
PRBool& aIsWhitespaceResult)
{
NS_PRECONDITION(mOffset <= mContentLength, "bad offset");
// See if the content has been exhausted
if (mOffset == mContentLength) {
aWordLenResult = 0;
aContentLenResult = 0;
return nsnull;
}
PRUnichar* bp = mBuffer;
PRUnichar* bufEnd = mBuffer + mBufferLength;
const nsTextFragment* frag = mCurrentFrag;
const nsTextFragment* lastFrag = mFrags + mNumFrags;
PRInt32 wordLen = 1;
PRInt32 contentLen = 1;
// Set the isWhitespace flag by examining the next character in the
// text fragment.
PRInt32 offset = mCurrentFragOffset;
PRUnichar firstChar;
if (frag->Is2b()) {
const PRUnichar* up = frag->Get2b();
firstChar = up[offset];
}
else {
const unsigned char* cp = (const unsigned char*) frag->Get1b();
firstChar = PRUnichar(cp[offset]);
}
PRBool isWhitespace = XP_IS_SPACE(firstChar);
offset++;
if (isWhitespace) {
if (NS_STYLE_WHITESPACE_PRE == mWhiteSpace) {
if ('\t' == firstChar) {
// Leave tab alone so that caller can expand it
}
else if ('\n' == firstChar) {
// Advance content past newline but do not allow newline to
// remain in the word.
wordLen--;
}
else {
firstChar = ' ';
}
}
else {
firstChar = ' ';
}
}
else if (CH_NBSP == firstChar) {
firstChar = ' ';
}
else {
switch (mTextTransform) {
case NS_STYLE_TEXT_TRANSFORM_LOWERCASE:
if (XP_IS_UPPERCASE(firstChar)) {
firstChar = XP_TO_LOWER(firstChar);
}
break;
case NS_STYLE_TEXT_TRANSFORM_UPPERCASE:
if (XP_IS_LOWERCASE(firstChar)) {
firstChar = XP_TO_UPPER(firstChar);
}
break;
}
}
*bp++ = firstChar;
if (offset == frag->GetLength()) {
mCurrentFrag = ++frag;
offset = 0;
}
mCurrentFragOffset = offset;
if (isWhitespace && (NS_STYLE_WHITESPACE_PRE == mWhiteSpace)) {
goto really_done;
}
PRInt32 numChars;
while (frag < lastFrag) {
PRInt32 fragLen = frag->GetLength();
// Scan characters in this fragment that are the same kind as the
// isWhitespace flag indicates.
if (frag->Is2b()) {
const PRUnichar* cp0 = frag->Get2b();
const PRUnichar* end = cp0 + fragLen;
const PRUnichar* cp = cp0 + offset;
if (isWhitespace) {
while (cp < end) {
PRUnichar ch = *cp;
if (XP_IS_SPACE(ch)) {
cp++;
continue;
}
numChars = (cp - offset) - cp0;
contentLen += numChars;
mCurrentFragOffset += numChars;
goto done;
}
numChars = (cp - offset) - cp0;
contentLen += numChars;
}
else {
while (cp < end) {
PRUnichar ch = *cp;
if (!XP_IS_SPACE(ch)) {
if (CH_NBSP == ch) ch = ' ';
if (ch > MAX_UNIBYTE) mHasMultibyte = PR_TRUE;
cp++;
switch (mTextTransform) {
case NS_STYLE_TEXT_TRANSFORM_LOWERCASE:
if (XP_IS_UPPERCASE(ch)) {
ch = XP_TO_LOWER(ch);
}
break;
case NS_STYLE_TEXT_TRANSFORM_UPPERCASE:
if (XP_IS_LOWERCASE(ch)) {
ch = XP_TO_UPPER(ch);
}
break;
}
// Store character in buffer; grow buffer if we have to
NS_ASSERTION(bp < bufEnd, "whoops");
*bp++ = ch;
if (bp == bufEnd) {
PRInt32 delta = bp - mBuffer;
if (!GrowBuffer()) {
goto done;
}
bp = mBuffer + delta;
bufEnd = mBuffer + mBufferLength;
}
continue;
}
numChars = (cp - offset) - cp0;
wordLen += numChars;
contentLen += numChars;
mCurrentFragOffset += numChars;
goto done;
}
numChars = (cp - offset) - cp0;
wordLen += numChars;
contentLen += numChars;
}
}
else {
const unsigned char* cp0 = (const unsigned char*) frag->Get1b();
const unsigned char* end = cp0 + fragLen;
const unsigned char* cp = cp0 + offset;
if (isWhitespace) {
while (cp < end) {
PRUnichar ch = PRUnichar(*cp);
if (XP_IS_SPACE(ch)) {
cp++;
continue;
}
numChars = (cp - offset) - cp0;
contentLen += numChars;
mCurrentFragOffset += numChars;
goto done;
}
numChars = (cp - offset) - cp0;
contentLen += numChars;
}
else {
while (cp < end) {
PRUnichar ch = PRUnichar(*cp);
if (!XP_IS_SPACE(ch)) {
if (CH_NBSP == ch) ch = ' ';
if (ch > MAX_UNIBYTE) mHasMultibyte = PR_TRUE;
cp++;
switch (mTextTransform) {
case NS_STYLE_TEXT_TRANSFORM_LOWERCASE:
if (XP_IS_UPPERCASE(ch)) {
ch = XP_TO_LOWER(ch);
}
break;
case NS_STYLE_TEXT_TRANSFORM_UPPERCASE:
if (XP_IS_LOWERCASE(ch)) {
ch = XP_TO_UPPER(ch);
}
break;
}
// Store character in buffer; grow buffer if we have to
NS_ASSERTION(bp < bufEnd, "whoops");
*bp++ = ch;
if (bp == bufEnd) {
PRInt32 delta = bp - mBuffer;
if (!GrowBuffer()) {
goto done;
}
bp = mBuffer + delta;
bufEnd = mBuffer + mBufferLength;
}
continue;
}
numChars = (cp - offset) - cp0;
wordLen += numChars;
contentLen += numChars;
mCurrentFragOffset += numChars;
goto done;
}
numChars = (cp - offset) - cp0;
wordLen += numChars;
contentLen += numChars;
}
}
// Advance to next text fragment
frag++;
mCurrentFrag = frag;
mCurrentFragOffset = 0;
offset = 0;
}
done:;
if (!aInWord && !isWhitespace &&
(NS_STYLE_TEXT_TRANSFORM_CAPITALIZE == mTextTransform)) {
PRInt32 n = wordLen;
PRUnichar* bp = mBuffer;
for (; --n >= 0; bp++) {
PRUnichar ch = *bp;
if (' ' == ch) {
// Skip over NBSP's that were mapped to space
continue;
}
if (XP_IS_LOWERCASE(ch)) {
*bp = XP_TO_UPPER(ch);
}
break;
}
}
really_done:;
mOffset += contentLen;
NS_ASSERTION(mOffset <= mContentLength, "whoops");
aWordLenResult = wordLen;
aContentLenResult = contentLen;
aIsWhitespaceResult = isWhitespace;
return mBuffer;
}
PRUnichar*
nsTextTransformer::GetTextAt(PRInt32 aOffset)
{
// XXX
return mBuffer + aOffset;
}