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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
 * under the License.
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 *************************************************************/



#include "precompiled_xmloff.hxx"

#include "RDFaExportHelper.hxx"

#include "xmloff/xmlnmspe.hxx"

#include <xmloff/xmlexp.hxx>
#include <xmloff/xmltoken.hxx>

#include <comphelper/stlunosequence.hxx>
#include <comphelper/stl_types.hxx>

#include <com/sun/star/uri/XUriReference.hpp>
#include <com/sun/star/uri/XUriReferenceFactory.hpp>
#include <com/sun/star/rdf/Statement.hpp>
#include <com/sun/star/rdf/URIs.hpp>
#include <com/sun/star/rdf/URI.hpp>
#include <com/sun/star/rdf/XLiteral.hpp>
#include <com/sun/star/rdf/XRepositorySupplier.hpp>
#include <com/sun/star/rdf/XDocumentRepository.hpp>

#include <rtl/ustrbuf.hxx>

#include <boost/bind.hpp>
#include <boost/iterator_adaptors.hpp>
#ifndef BOOST_ITERATOR_ADAPTOR_DWA053000_HPP_ // from iterator_adaptors.hpp
// N.B.: the check for the header guard _of a specific version of boost_
//       is here so this may work on different versions of boost,
//       which sadly put the goods in different header files
#include <boost/iterator/transform_iterator.hpp>
#endif

#include <functional>
#include <algorithm>


using namespace ::com::sun::star;

namespace xmloff {

static const char s_prefix [] = "_:b";

static ::rtl::OUString
makeCURIE(SvXMLExport * i_pExport,
    uno::Reference<rdf::XURI> const & i_xURI)
{
    OSL_ENSURE(i_xURI.is(), "makeCURIE: null URI");
    if (!i_xURI.is()) throw uno::RuntimeException();

    const ::rtl::OUString Namespace( i_xURI->getNamespace() );
    OSL_ENSURE(Namespace.getLength(), "makeCURIE: no namespace");
    if (!Namespace.getLength()) throw uno::RuntimeException();

    ::rtl::OUStringBuffer buf;
    buf.append( i_pExport->EnsureNamespace(Namespace) );
    buf.append( static_cast<sal_Unicode>(':') );
    // N.B.: empty LocalName is valid!
    buf.append( i_xURI->getLocalName() );

    return buf.makeStringAndClear();
}

// #i112473# SvXMLExport::GetRelativeReference() not right for RDF on SaveAs
// because the URIs in the repository are not rewritten on SaveAs, the
// URI of the loaded document has to be used, not the URI of the target doc.
static ::rtl::OUString
getRelativeReference(SvXMLExport const& rExport, ::rtl::OUString const& rURI)
{
    uno::Reference< rdf::XURI > const xModelURI(
        rExport.GetModel(), uno::UNO_QUERY_THROW );
    ::rtl::OUString const baseURI( xModelURI->getStringValue() );

    uno::Reference<uno::XComponentContext> const xContext(
        rExport.GetComponentContext());
    uno::Reference<lang::XMultiComponentFactory> const xServiceFactory(
        xContext->getServiceManager(), uno::UNO_SET_THROW);
    uno::Reference<uri::XUriReferenceFactory> const xUriFactory(
        xServiceFactory->createInstanceWithContext(
            ::rtl::OUString::createFromAscii(
                "com.sun.star.uri.UriReferenceFactory"), xContext),
        uno::UNO_QUERY_THROW);

    uno::Reference< uri::XUriReference > const xBaseURI(
        xUriFactory->parse(baseURI), uno::UNO_SET_THROW );
    uno::Reference< uri::XUriReference > const xAbsoluteURI(
        xUriFactory->parse(rURI), uno::UNO_SET_THROW );
    uno::Reference< uri::XUriReference > const xRelativeURI(
        xUriFactory->makeRelative(xBaseURI, xAbsoluteURI, true, true, false),
        uno::UNO_SET_THROW );
    ::rtl::OUString const relativeURI(xRelativeURI->getUriReference());

    return relativeURI;
}


////////////////////////////////////////////////////////////////////////////

RDFaExportHelper::RDFaExportHelper(SvXMLExport & i_rExport)
    : m_rExport(i_rExport), m_xRepository(0), m_Counter(0)
{
    const uno::Reference<rdf::XRepositorySupplier> xRS( m_rExport.GetModel(),
            uno::UNO_QUERY);
    OSL_ENSURE(xRS.is(), "AddRDFa: model is no rdf::XRepositorySupplier");
    if (!xRS.is()) throw uno::RuntimeException();
    m_xRepository.set(xRS->getRDFRepository(), uno::UNO_QUERY_THROW);
}

::rtl::OUString
RDFaExportHelper::LookupBlankNode(
    uno::Reference<rdf::XBlankNode> const & i_xBlankNode)
{
    OSL_ENSURE(i_xBlankNode.is(), "null BlankNode?");
    if (!i_xBlankNode.is()) throw uno::RuntimeException();
    ::rtl::OUString & rEntry(
        m_BlankNodeMap[ i_xBlankNode->getStringValue() ] );
    if (!rEntry.getLength())
    {
        ::rtl::OUStringBuffer buf;
        buf.appendAscii(s_prefix);
        buf.append(++m_Counter);
        rEntry = buf.makeStringAndClear();
    }
    return rEntry;
}

////////////////////////////////////////////////////////////////////////////

void
RDFaExportHelper::AddRDFa(
    uno::Reference<rdf::XMetadatable> const & i_xMetadatable)
{
    try
    {
        beans::Pair< uno::Sequence<rdf::Statement>, sal_Bool > const
            RDFaResult( m_xRepository->getStatementRDFa(i_xMetadatable) );

        uno::Sequence<rdf::Statement> const & rStatements( RDFaResult.First );

        if (0 == rStatements.getLength())
        {
            return; // no RDFa
        }

        // all stmts have the same subject, so we only handle first one
        const uno::Reference<rdf::XURI> xSubjectURI(rStatements[0].Subject,
            uno::UNO_QUERY);
        const uno::Reference<rdf::XBlankNode> xSubjectBNode(
            rStatements[0].Subject, uno::UNO_QUERY);
        if (!xSubjectURI.is() && !xSubjectBNode.is())
        {
            throw uno::RuntimeException();
        }
        static const sal_Unicode s_OpenBracket ('[');
        static const sal_Unicode s_CloseBracket(']');
        const ::rtl::OUString about( xSubjectURI.is()
            ?   getRelativeReference(m_rExport, xSubjectURI->getStringValue())
            :   ::rtl::OUStringBuffer().append(s_OpenBracket).append(
                        LookupBlankNode(xSubjectBNode)).append(s_CloseBracket)
                    .makeStringAndClear()
            );

        const uno::Reference<rdf::XLiteral> xContent(
            rStatements[0].Object, uno::UNO_QUERY_THROW );
        const uno::Reference<rdf::XURI> xDatatype(xContent->getDatatype());
        if (xDatatype.is())
        {
            const ::rtl::OUString datatype(
                makeCURIE(&m_rExport, xDatatype) );
            m_rExport.AddAttribute(XML_NAMESPACE_XHTML,
                token::XML_DATATYPE, datatype);
        }
        if (RDFaResult.Second) // there is xhtml:content
        {
            m_rExport.AddAttribute(XML_NAMESPACE_XHTML, token::XML_CONTENT,
                xContent->getValue());
        }

        ::rtl::OUStringBuffer property;
        ::comphelper::intersperse(
            ::boost::make_transform_iterator(
                ::comphelper::stl_begin(rStatements),
                ::boost::bind(&makeCURIE, &m_rExport,
                    ::boost::bind(&rdf::Statement::Predicate, _1))),
            // argh, this must be the same type :(
            ::boost::make_transform_iterator(
                ::comphelper::stl_end(rStatements),
                ::boost::bind(&makeCURIE, &m_rExport,
                    ::boost::bind(&rdf::Statement::Predicate, _1))),
            ::comphelper::OUStringBufferAppender(property),
            ::rtl::OUString::createFromAscii(" "));

        m_rExport.AddAttribute(XML_NAMESPACE_XHTML, token::XML_PROPERTY,
            property.makeStringAndClear());

        m_rExport.AddAttribute(XML_NAMESPACE_XHTML, token::XML_ABOUT, about);
    }
    catch (uno::Exception &)
    {
        OSL_ENSURE(false, "AddRDFa: exception");
    }
}

} // namespace xmloff