/***************************************************************************
 *   Copyright (C) 2005 by Joris Guisson                                   *
 *   joris.guisson@gmail.com                                               *
 *   ivasic@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, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.             *
 ***************************************************************************/
#ifndef ANTIP2P_H
#define ANTIP2P_H

#include <util/mmapfile.h>
#include <util/constants.h>

#include <qlist.h>
#include <qstring.h>
#include <interfaces/blocklistinterface.h>

namespace kt
{
    struct HeaderBlock
    {
        bt::Uint32 ip1;
        bt::Uint32 ip2;
        bt::Uint64 offset;
        bt::Uint32 nrEntries;
    };

    struct IPBlock
    {
        bt::Uint32 ip1;
        bt::Uint32 ip2;

        IPBlock();
        IPBlock(const IPBlock& block);
        IPBlock(const QString& start, const QString& end);
    };

    /**
     * @author Ivan Vasic <ivasic@gmail.com>
     * @brief This class is used to manage anti-p2p filter list, so called level1.
     */
    class AntiP2P : public bt::BlockListInterface
    {
    public:
        AntiP2P();
        virtual ~AntiP2P();

        virtual bool blocked(const net::Address& addr) const;

        /**
         * Checks if anti-p2p file is present. Used to check if we should use level1 list
         **/
        bool exists();


        /**
         * Creates and loads the header from antip2p filter file.
         **/
        void loadHeader();

        /**
         * Overloaded function. Uses Uint32 IP to be checked
         **/
        bool isBlockedIP(bt::Uint32 ip);

    private:
        ///Is AntiP2P header loaded
        bool header_loaded;

        /**
         * Loads filter file
         */
        void load();

        /**
         * Binary searches AntiP2P::blocks to find range where IP could be.
         * @returns
         *  -1 if IP cannot be in the list
         *  -2 if IP is already found in blocks
         *  or index of HeaderBlock in AntiP2P::blocks which will be used for direct file search.
         **/
        int searchHeader(bt::Uint32& ip, int start, int end) const;


        /**
         * Binary searches AntiP2P::file to find IP.
         * @returns TRUE if IP should be blocked FALSE otherwise
         **/
        bool searchFile(IPBlock* file_blocks, bt::Uint32& ip, int start, int end) const;

    private:
        bt::MMapFile* file;
        QList<HeaderBlock> blocks;
    };
}
#endif
