/****************************************************************************
**
** Copyright (C) 2010 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.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.

#ifndef Patternist_SourceLocationReflection_H
#define Patternist_SourceLocationReflection_H

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

class QString;

namespace QPatternist
{
    /**
     * @short Base class for all instances that represents something
     * at a certain location.
     *
     * SourceLocationReflection does not provide the source location itself,
     * the address to an instance is the mark for it, that in turn can be used
     * for looking up the source location where that mapping is provided.
     *
     * However, this SourceLocationReflection is not itself the mark. The real
     * mark is retrieved by calling actualReflection(). This mechanism
     * allows a SourceLocationReflection sub-class to delegate, or be an alias,
     * for another source location mark.
     *
     * If sourceLocation() returns a non-null object, it will be used instead
     * of looking up via actualReflection().
     *
     * @author Frans Englich <frans.englich@nokia.com>
     * @ingroup Patternist_expressions
     */
    class Q_AUTOTEST_EXPORT SourceLocationReflection
    {
    public:
        inline SourceLocationReflection()
        {
        }

        virtual ~SourceLocationReflection()
        {
        }

        virtual const SourceLocationReflection *actualReflection() const = 0;

        /**
         * A description of what represents the source code location, for
         * human consumption. Must be translated, as appropriate.
         */
        virtual QString description() const
        {
            return QString();
        }

        virtual QSourceLocation sourceLocation() const;

    private:
        Q_DISABLE_COPY(SourceLocationReflection)
    };

    class DelegatingSourceLocationReflection : public SourceLocationReflection
    {
    public:
        inline DelegatingSourceLocationReflection(const SourceLocationReflection *const r) : m_r(r)
        {
            Q_ASSERT(r);
        }

        virtual const SourceLocationReflection *actualReflection() const;
        virtual QString description() const;

    private:
        const SourceLocationReflection *const m_r;
    };

}

QT_END_NAMESPACE

QT_END_HEADER

#endif
