gecko-dev/editor/base/nsWrapUtils.cpp

136 lines
4.7 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: NPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Netscape Public License
* Version 1.1 (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.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the NPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the NPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsWrapUtils.h"
#include "nsCOMPtr.h"
// Line breaker stuff
#include "nsIServiceManager.h"
#include "nsILineBreakerFactory.h"
#include "nsLWBrkCIID.h"
static NS_DEFINE_CID(kLWBrkCID, NS_LWBRK_CID);
/*
* Rewrap the given section of string, putting the result in aOutString.
*/
nsresult
nsWrapUtils::Rewrap(const nsAReadableString& aInString,
PRUint32 aWrapCol, PRUint32 aFirstLineOffset,
PRBool aRespectNewlines,
const nsAReadableString &aLineStartStr,
nsAWritableString& aOutString)
{
PRInt32 i;
nsCOMPtr<nsILineBreaker> lineBreaker;
nsILineBreakerFactory *lf;
nsresult rv = NS_OK;
rv = nsServiceManager::GetService(kLWBrkCID,
NS_GET_IID(nsILineBreakerFactory),
(nsISupports **)&lf);
if (NS_SUCCEEDED(rv))
{
nsAutoString lbarg;
rv = lf->GetBreaker(lbarg, getter_AddRefs(lineBreaker));
nsServiceManager::ReleaseService(kLWBrkCID, lf);
}
aOutString.SetLength(0);
// Now we either have a line breaker, or we don't.
PRInt32 length = aInString.Length();
nsString tString(aInString);
const PRUnichar* unicodeStr = tString.get();
for (i = 0; i < length; ) // loop over lines
{
nsAutoString remaining(unicodeStr + i, length - i);
// If there's a first-line offset, that means we're not starting
// at the beginning of the line, so don't add a cite string there:
if (!aFirstLineOffset)
aOutString.Append(aLineStartStr);
PRInt32 eol = i + aWrapCol - aFirstLineOffset;
if (eol > length)
{
aOutString.Append(unicodeStr + i, length - i);
aOutString.Append(PRUnichar('\n')); // DOM line breaks, not NS_LINEBREAK
break;
}
if (i > 0) aFirstLineOffset = 0;
// eol is the prospective end of line ...
// look backwards from there for a place to break.
PRUint32 breakPt;
PRBool needMore;
rv = NS_ERROR_BASE;
if (lineBreaker)
{
rv = lineBreaker->Prev(unicodeStr + i, length - i, eol - i,
&breakPt, &needMore);
if (NS_FAILED(rv) || needMore)
{
rv = lineBreaker->Next(unicodeStr + i, length - i, eol - i,
&breakPt, &needMore);
if (needMore) rv = NS_ERROR_BASE;
}
}
// If we get out here and rv is set, something went wrong with line breaker.
// Just break the line, hard.
// If rv is okay, then breakPt is the place to break.
if (NS_FAILED(rv))
{
#ifdef DEBUG_akkana
printf("nsILineBreaker not working -- breaking hard\n");
#endif
breakPt = eol+1;
}
else breakPt += i;
nsAutoString appending(unicodeStr + i, breakPt - i);
aOutString.Append(unicodeStr + i, breakPt - i);
aOutString.Append(PRUnichar('\n')); // DOM line breaks, not NS_LINEBREAK
i = breakPt;
} // continue looping over lines
return NS_OK;
}