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 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
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// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_forms.hxx"

#include "pathexpression.hxx"
#include "unohelper.hxx"
#include "evaluationcontext.hxx"
#include "NameContainer.hxx"

#include <com/sun/star/xml/dom/XNode.hpp>
#include <com/sun/star/xml/dom/XNodeList.hpp>
#include <com/sun/star/xml/dom/NodeType.hpp>
#include <com/sun/star/xml/dom/events/XEventListener.hpp>
#include <com/sun/star/xml/dom/events/XEventTarget.hpp>
#include <com/sun/star/xml/xpath/XXPathObject.hpp>
#include <com/sun/star/container/XNameContainer.hpp>
#include <com/sun/star/uno/Sequence.hxx>
#include <rtl/ustrbuf.hxx>

#include <unotools/textsearch.hxx>

#include <algorithm>
#include <functional>


using rtl::OUString;
using rtl::OUStringBuffer;
using com::sun::star::uno::Reference;
using com::sun::star::uno::Sequence;
using com::sun::star::xml::dom::XNode;
using com::sun::star::xml::dom::XNodeList;
using com::sun::star::xml::dom::events::XEventListener;
using com::sun::star::xml::dom::events::XEventTarget;
using com::sun::star::container::XNameContainer;
using com::sun::star::xml::xpath::XXPathObject;
using com::sun::star::uno::RuntimeException;
using com::sun::star::uno::UNO_QUERY;
using com::sun::star::uno::UNO_QUERY_THROW;
using com::sun::star::xml::dom::NodeType_TEXT_NODE;
using com::sun::star::xml::xpath::XPathObjectType_XPATH_UNDEFINED;
using namespace std;


namespace xforms
{

PathExpression::PathExpression() 
    : ComputedExpression(),
      maNodes()
{
}

PathExpression::~PathExpression()
{
}


void PathExpression::setExpression( const OUString& rExpression )
{
    // set new expression, and clear pre-computed results
    ComputedExpression::setExpression( rExpression );

    // check expression against regular expression to determine
    // whether it contains only 'simple' (i.e. static) conditions. For
    // now, we check whether it only contains number positions.
    // (TODO: Only works for names containing only ASCII letters+digits.)
    mbIsSimple = 
        _checkExpression( "( */@?[a-zA-Z0-9:]+( *\\[ *[0-9 ]+ *\\] *)?)+" );

    maNodes.clear();
}

const rtl::OUString PathExpression::_getExpressionForEvaluation() const
{
    OUString sExpr = ComputedExpression::_getExpressionForEvaluation();
    if( sExpr.getLength() == 0 )
        sExpr = OUSTRING(".");
    return sExpr;
}

bool PathExpression::evaluate( const EvaluationContext& rContext )
{
    // for simple expression we don't need to re-bind (if we were bound before)
    // (we will evaluate empty expressions, since they are interpreted as ".")
    if( mxResult.is() && isSimpleExpression() )
        return true;

    bool bResult = _evaluate( rContext, _getExpressionForEvaluation() );

    // clear old result, and copy new
    maNodes.clear();
    if( mxResult.is() )
    {
        // copy node list
        Reference<XNodeList> xNodeList = mxResult->getNodeList();
        OSL_ENSURE( xNodeList.is(), "empty object (instead of empty list)" );
        sal_Int32 nLength = xNodeList.is() ? xNodeList->getLength() : 0;
        for( sal_Int32 n = 0; n < nLength; n++ )
            maNodes.push_back( xNodeList->item( n ) );
    }

    return bResult;
}


Reference<XNode> PathExpression::getNode() const
{
    Reference<XNode> xResult;
    if( ! maNodes.empty() )
        xResult = *maNodes.begin();
    return xResult;
}

const PathExpression::NodeVector_t PathExpression::getNodeList() const
{
    return maNodes;
}

Reference<XNodeList> PathExpression::getXNodeList() const
{
    return mxResult.is() ? mxResult->getNodeList() : Reference<XNodeList>();
}


} // namespace xforms