/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   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 .
 */

#ifndef _MODELTOVIEWHELPER_HXX
#define _MODELTOVIEWHELPER_HXX

#include <rtl/ustring.hxx>
#include <sal/types.h>
#include <vector>

class SwTxtNode;

/** Some helpers for converting model strings to view strings.

    A paragraph string does not have its fields expanded, i.e., they are
    represented by a special character inside the string with an additional
    attribute assigned to it. For some tasks (e.g., SmartTags) it is required
    to expand the fields to get the string as it appears in the view. Two
    helper functions are provided to convert model positions to view positions
    and vice versa.
*/
class ModelToViewHelper
{
    /** For each field in the model string, there is an entry in the conversion
        map. The first value of the ConversionMapEntry points to the field
        position in the model string, the second value points to the associated
        position in the view string. The last entry in the conversion map
        denotes the lengths of the model resp. view string.
    */
    typedef std::pair< sal_uInt32 , sal_uInt32 > ConversionMapEntry;
    typedef std::vector< ConversionMapEntry > ConversionMap;

    ConversionMap m_aMap;

    rtl::OUString m_aRetText;

public:

    /** This struct defines a position in the model string.

        The 'main' position is given by mnPos. If there's a field located at
        this position, mbIsField is set and mnSubPos denotes the position inside
        that field.
    */
    struct ModelPosition
    {
        sal_uInt32 mnPos;
        sal_uInt32 mnSubPos;
        bool mbIsField;

        ModelPosition() : mnPos(0), mnSubPos(0), mbIsField(false) {}
    };

    ModelToViewHelper(const SwTxtNode &rNode);
    ModelToViewHelper() {}   //pass through filter, view == model

    /** Converts a model position into a view position

        @param nPos
            nPos denotes a position in the model string which should be
            converted. Note that converting model positions inside fields is
            not supported, therefore nPos is not of type ModelPosition.

        @return
            the position of nPos in the view string. In case the conversion
            could not be performed (e.g., because there is not ConversionMap or
            nPos is behind the last entry in the conversion map) nPos will
            be returned.
    */
    sal_uInt32 ConvertToViewPosition( sal_uInt32 nModelPos ) const;

    /** Converts a view position into a model position

        @param nPos
            nPos denotes a position in the view string which should be
            converted.

        @return
            the position of nPos in the model string. In case the conversion
            could not be performed (e.g., because there is not ConversionMap or
            nPos is behind the last entry in the conversion map) a model
            model position with mnPos = nPos and mnIsField = false will be
            returned.
    */
    ModelPosition ConvertToModelPosition( sal_uInt32 nViewPos ) const;

    rtl::OUString getViewText() const { return m_aRetText; }
};

#endif

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