/*
 * 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 under the License.
 */
#include "FunctionDistinct.hpp"


#include <xalanc/Include/XalanSet.hpp>


#include <xalanc/XalanDOM/XalanDOMString.hpp>


#include <xalanc/PlatformSupport/XalanMessageLoader.hpp>
#include <xalanc/PlatformSupport/DOMStringHelper.hpp>


#include <xalanc/DOMSupport/DOMServices.hpp>


#include <xalanc/XPath/XPathExecutionContext.hpp>
#include <xalanc/XPath/XObjectFactory.hpp>


namespace XALAN_CPP_NAMESPACE {


FunctionDistinct::FunctionDistinct()
{
}


FunctionDistinct::~FunctionDistinct()
{
}


XObjectPtr
FunctionDistinct::execute(
            XPathExecutionContext&          executionContext,
            XalanNode*                      context,
            const XObjectArgVectorType&     args,
            const Locator*                  locator) const
{
    if (args.size() != 1)
    {
        generalError(
            executionContext,
            context,
            locator);
    }

    assert(args[0].null() == false);

    const NodeRefListBase&  nodeset = args[0]->nodeset();

    typedef XPathExecutionContext::BorrowReturnMutableNodeRefList   BorrowReturnMutableNodeRefList;

    BorrowReturnMutableNodeRefList  theResult(executionContext);

    const NodeRefListBase::size_type    theLength = nodeset.getLength();

    if (theLength == 1)
    {
        theResult->addNode(nodeset.item(0));
    }
    else if (theLength > 1)
    {
        const GetCachedString   theGuard(executionContext);

        XalanDOMString&         theCachedString = theGuard.get();


        typedef XalanSet<XalanDOMString>    SetType;

        SetType     theStrings(executionContext.getMemoryManager());

        // Check to make sure each node has a unique
        // string value.
        for (NodeRefListBase::size_type i = 0; i < theLength; ++i)
        {
            XalanNode* const    theNode = nodeset.item(i);
            assert(theNode != 0);

            DOMServices::getNodeData(*theNode, executionContext, theCachedString);

            if (theStrings.find(theCachedString) == theStrings.end())
            {
                theResult->addNodeInDocOrder(theNode, executionContext);

                theStrings.insert(theCachedString);
            }


            theCachedString.clear();
        }
    }

    theResult->setDocumentOrder();

    return executionContext.getXObjectFactory().createNodeSet(theResult);
}


#if defined(XALAN_NO_COVARIANT_RETURN_TYPE)
Function*
#else
FunctionDistinct*
#endif
FunctionDistinct::clone(MemoryManager&  theManager) const
{
    return XalanCopyConstruct(theManager, *this);
}


const XalanDOMString&
FunctionDistinct::getError(XalanDOMString&  theResult) const
{

    return XalanMessageLoader::getMessage(
                theResult,
                XalanMessages::FunctionAcceptsOneArgument_1Param,
                "distinct");
}


}