/****************************************************************************************

 * Copyright (c) 2006 Gbor Lehel <illissius@gmail.com>                                  *

 *                                                                                      *

 * This program is free software; you can redistribute it and/or modify it under        *

 * the terms of the GNU General Public License as published by the Free Software        *

 * Foundation; either version 2 of the License, or (at your option) any later           *

 * version.                                                                             *

 *                                                                                      *

 * This program is distributed in the hope that it will be useful, but WITHOUT ANY      *

 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A      *

 * PARTICULAR PURPOSE. See the GNU General Public License for more details.             *

 *                                                                                      *

 * You should have received a copy of the GNU General Public License along with         *

 * this program.  If not, see <http://www.gnu.org/licenses/>.                           *

 ****************************************************************************************/

#ifndef AMAROK_EXPRESSION_H

#define AMAROK_EXPRESSION_H

#include <QList>

#include <QString>

struct expression_element

{

    QString field;

    QString text;

    bool negate: 1;

    enum { Contains, Less, More } match: 2;

    expression_element(): negate( false ), match( Contains ) { }

};

typedef QList<expression_element> or_list;

typedef QList<or_list> ParsedExpression;

class ExpressionParser

{

    public:

        ExpressionParser( const QString &expression );

        ParsedExpression parse();

        static ParsedExpression parse( const QString &expression );

        static bool isAdvancedExpression( const QString &expression );

    private:

        void parseChar(   const QChar &c );

        void handleSpace( const QChar &c );

        void handleMinus( const QChar &c );

        void handleColon( const QChar &c );

        void handleMod(   const QChar &c );

        void handleQuote( const QChar &c );

        void handleChar(  const QChar &c );

        void finishedToken();

        void finishedElement();

        void finishedOrGroup();

        const QString &m_expression;

        enum State { ExpectMinus, ExpectField, ExpectMod, ExpectText };

        int m_state;

        bool m_haveGroup;

        bool m_inQuote;

        bool m_inOrGroup;

        QString m_string;

        expression_element m_element;

        or_list m_or;

        ParsedExpression m_parsed;

};

#endif