Source/WebCore/editing/SplitTextNodeCommand.cpp

/*
 * Copyright (C) 2005, 2008 Apple Inc. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
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 * 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
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#include "config.h"
#include "SplitTextNodeCommand.h"

#include "Document.h"
#include "DocumentMarkerController.h"
#include "Text.h"
#include <wtf/Assertions.h>

namespace WebCore {

SplitTextNodeCommand::SplitTextNodeCommand(PassRefPtr<Text> text, int offset)
    : SimpleEditCommand(text->document())
    , m_text2(text)
    , m_offset(offset)
{
    // NOTE: Various callers rely on the fact that the original node becomes
    // the second node (i.e. the new node is inserted before the existing one).
    // That is not a fundamental dependency (i.e. it could be re-coded), but
    // rather is based on how this code happens to work.
    ASSERT(m_text2);
    ASSERT(m_text2->length() > 0);
    ASSERT(m_offset > 0);
    ASSERT(m_offset < m_text2->length());
}

void SplitTextNodeCommand::doApply()
{
    ContainerNode* parent = m_text2->parentNode();
    if (!parent || !parent->rendererIsEditable())
        return;

    ExceptionCode ec = 0;
    String prefixText = m_text2->substringData(0, m_offset, ec);
    if (prefixText.isEmpty())
        return;

    m_text1 = Text::create(document(), prefixText);
    ASSERT(m_text1);
    document()->markers()->copyMarkers(m_text2.get(), 0, m_offset, m_text1.get(), 0);

    insertText1AndTrimText2();
}

void SplitTextNodeCommand::doUnapply()
{
    if (!m_text1 || !m_text1->rendererIsEditable())
        return;

    ASSERT(m_text1->document() == document());

    String prefixText = m_text1->data();

    ExceptionCode ec = 0;
    m_text2->insertData(0, prefixText, ec);
    ASSERT(!ec);

    document()->markers()->copyMarkers(m_text1.get(), 0, prefixText.length(), m_text2.get(), 0);
    m_text1->remove(ec);
}

void SplitTextNodeCommand::doReapply()
{
    if (!m_text1 || !m_text2)
        return;

    ContainerNode* parent = m_text2->parentNode();
    if (!parent || !parent->rendererIsEditable())
        return;

    insertText1AndTrimText2();
}

void SplitTextNodeCommand::insertText1AndTrimText2()
{
    ExceptionCode ec = 0;
    m_text2->parentNode()->insertBefore(m_text1.get(), m_text2.get(), ec);
    if (ec)
        return;
    m_text2->deleteData(0, m_offset, ec);
}
    
} // namespace WebCore