/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtXmlPatterns module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "qdocumentprojector_p.h"
QT_BEGIN_NAMESPACE
using namespace QPatternist;
DocumentProjector::DocumentProjector(const ProjectedExpression::Vector &paths,
QAbstractXmlReceiver *const receiver) : m_paths(paths)
, m_pathCount(paths.count())
, m_action(ProjectedExpression::Move)
, m_nodesInProcess(0)
, m_receiver(receiver)
{
Q_ASSERT_X(paths.count() > 0, Q_FUNC_INFO,
"Using DocumentProjector with no paths is an "
"overhead and has also undefined behavior.");
Q_ASSERT(m_receiver);
}
void DocumentProjector::startElement(const QXmlName name)
{
Q_UNUSED(name);
switch(m_action)
{
case ProjectedExpression::KeepSubtree:
{
m_receiver->startElement(name);
/* Fallthrough. */
}
case ProjectedExpression::Skip:
{
++m_nodesInProcess;
return;
}
default:
{
Q_ASSERT_X(m_action == ProjectedExpression::Move, Q_FUNC_INFO,
"We're not supposed to receive Keep here, because "
"endElement() should always end that state.");
for(int i = 0; i < m_pathCount; ++i)
{
m_action = m_paths.at(i)->actionForElement(name, m_paths[i]);
switch(m_action)
{
case ProjectedExpression::Keep:
{
m_action = ProjectedExpression::Keep;
continue;
}
case ProjectedExpression::KeepSubtree:
{
/* Ok, at least one path wanted this node. Pass it on,
* and exit. */
m_receiver->startElement(name);
++m_nodesInProcess;
return;
}
case ProjectedExpression::Skip:
{
/* This particular path doesn't need it, but
* some other path might, so continue looping. */
continue;
}
case ProjectedExpression::Move:
Q_ASSERT_X(false, Q_FUNC_INFO, "The action functions can never return Move.");
}
}
++m_nodesInProcess;
if(m_action == ProjectedExpression::Keep)
m_receiver->startElement(name);
else
{
Q_ASSERT(m_action == ProjectedExpression::Skip);
}
}
}
}
void DocumentProjector::endElement()
{
if(m_action == ProjectedExpression::Keep)
{
Q_ASSERT(m_nodesInProcess == 1);
m_receiver->endElement();
/* We have now kept the single node, and now wants to skip
* all its children. */
m_action = ProjectedExpression::Skip;
m_nodesInProcess = 0;
}
else if(m_action == ProjectedExpression::KeepSubtree)
{
m_receiver->endElement();
--m_nodesInProcess;
if(m_nodesInProcess == 0)
{
/* We have now skipped all the children, let's do
* a new path analysis. */
m_action = ProjectedExpression::Move;
}
}
else
{
Q_ASSERT_X(m_action == ProjectedExpression::Skip, Q_FUNC_INFO,
"We're not supposed to be in a Move action here.");
/* We skip calling m_receiver's endElement() here since we're
* skipping. */
Q_ASSERT(m_nodesInProcess > 0);
--m_nodesInProcess;
if(m_nodesInProcess == 0)
{
/* Ok, we've skipped them all, let's do something
* new -- let's Move on to the next path! */
m_action = ProjectedExpression::Move;
}
}
}
void DocumentProjector::attribute(const QXmlName name,
const QString &value)
{
Q_UNUSED(name);
Q_UNUSED(value);
}
void DocumentProjector::namespaceBinding(const QXmlName nb)
{
Q_UNUSED(nb);
}
void DocumentProjector::comment(const QString &value)
{
Q_ASSERT_X(!value.contains(QLatin1String("--")), Q_FUNC_INFO,
"Invalid input; it's the caller's responsibility to ensure the input is correct.");
Q_UNUSED(value);
}
void DocumentProjector::characters(const QString &value)
{
Q_UNUSED(value);
}
void DocumentProjector::processingInstruction(const QXmlName name,
const QString &value)
{
Q_ASSERT_X(!value.contains(QLatin1String("?>")), Q_FUNC_INFO,
"Invalid input; it's the caller's responsibility to ensure the input is correct.");
Q_UNUSED(name);
Q_UNUSED(value);
}
void DocumentProjector::item(const Item &outputItem)
{
Q_UNUSED(outputItem);
}
void DocumentProjector::startDocument()
{
}
void DocumentProjector::endDocument()
{
}
QT_END_NAMESPACE