RetroZilla/editor/libeditor/text/nsTextEditRulesBidi.cpp
2015-10-20 23:03:22 -04:00

164 lines
5.2 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla 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/MPL/
*
* 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 of 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 MPL, 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
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*
* ***** END LICENSE BLOCK ***** */
#include "nsTextEditRules.h"
#include "nsCOMPtr.h"
#include "nsIDOMNode.h"
#include "nsIContent.h"
#include "nsIPresShell.h"
#include "nsPresContext.h"
#include "nsIFrame.h"
// Test for distance between caret and text that will be deleted
nsresult
nsTextEditRules::CheckBidiLevelForDeletion(nsIDOMNode *aSelNode,
PRInt32 aSelOffset,
nsIEditor::EDirection aAction,
PRBool *aCancel)
{
NS_ENSURE_ARG_POINTER(aCancel);
*aCancel = PR_FALSE;
nsCOMPtr<nsIPresShell> shell;
nsresult res = mEditor->GetPresShell(getter_AddRefs(shell));
if (NS_FAILED(res))
return res;
if (!shell)
return NS_ERROR_NULL_POINTER;
nsPresContext *context = shell->GetPresContext();
if (!context)
return NS_ERROR_NULL_POINTER;
if (!context->BidiEnabled())
return NS_OK;
nsCOMPtr<nsIContent> content = do_QueryInterface(aSelNode);
if (!content)
return NS_ERROR_NULL_POINTER;
if (content->IsContentOfType(nsIContent::eELEMENT))
{
content = content->GetChildAt(aSelOffset);
if (!content)
return NS_ERROR_FAILURE;
aSelOffset = 0;
}
nsIFrame *primaryFrame;
res = shell->GetPrimaryFrameFor(content, &primaryFrame);
if (NS_FAILED(res))
return res;
if (!primaryFrame)
return NS_ERROR_NULL_POINTER;
nsIFrame *frameBefore;
nsIFrame *frameAfter;
PRInt32 frameOffset;
res = primaryFrame->GetChildFrameContainingOffset(aSelOffset, PR_FALSE, &frameOffset, &frameBefore);
if (NS_FAILED(res))
return res;
if (!frameBefore)
return NS_ERROR_NULL_POINTER;
PRUint8 levelAfter;
nsCOMPtr<nsIAtom> embeddingLevel = do_GetAtom("EmbeddingLevel");
// Get the bidi level of the frame before the caret
PRUint8 levelBefore =
NS_PTR_TO_INT32(frameBefore->GetPropertyExternal(embeddingLevel, nsnull));
// If the caret is at the end of the frame, get the bidi level of the
// frame after the caret
PRInt32 start, end;
frameBefore->GetOffsets(start, end);
if (aSelOffset == end
|| aSelOffset == -1)
{
res = primaryFrame->GetChildFrameContainingOffset(aSelOffset, PR_TRUE, &frameOffset, &frameAfter);
if (NS_FAILED(res))
return res;
if (!frameAfter)
return NS_ERROR_NULL_POINTER;
if (frameBefore==frameAfter)
{
// there was no frameAfter, i.e. the caret is at the end of the
// document -- use the base paragraph level
nsCOMPtr<nsIAtom> baseLevel = do_GetAtom("BaseLevel");
levelAfter =
NS_PTR_TO_INT32(frameBefore->GetPropertyExternal(baseLevel, nsnull));
}
else
{
levelAfter =
NS_PTR_TO_INT32(frameAfter->GetPropertyExternal(embeddingLevel, nsnull));
}
}
else
{
levelAfter = levelBefore;
}
PRUint8 currentCursorLevel;
res = shell->GetCaretBidiLevel(&currentCursorLevel);
if (NS_FAILED(res))
return res;
PRUint8 levelOfDeletion;
levelOfDeletion = (nsIEditor::eNext==aAction) ? levelAfter : levelBefore;
if (currentCursorLevel == levelOfDeletion)
; // perform the deletion
else
{
if ((levelBefore==levelAfter)
&& (levelBefore & 1) == (currentCursorLevel & 1))
; // perform the deletion
else
*aCancel = PR_TRUE;
// Set the bidi level of the caret to that of the
// character that will be (or would have been) deleted
res = shell->SetCaretBidiLevel(levelOfDeletion);
if (NS_FAILED(res))
return res;
}
return NS_OK;
}