/***************************************************************************
 *   Copyright (C) 2005 by Joris Guisson                                   *
 *   joris.guisson@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 BTBENCODER_H
#define BTBENCODER_H

#include <ktorrent_export.h>
#include <util/file.h>

class QIODevice;

namespace bt
{
class File;

/**
 * @author Joris Guisson
 *
 * Interface for classes which wish to receive the output from a BEncoder.
 */
class KTORRENT_EXPORT BEncoderOutput
{
public:
    virtual ~BEncoderOutput() {}
    /**
     * Write a string of characters.
     * @param str The string
     * @param len The length of the string
     */
    virtual void write(const char* str, Uint32 len) = 0;
};

/**
 * Writes the output of a bencoder to a file
 */
class KTORRENT_EXPORT BEncoderFileOutput : public BEncoderOutput
{
    File* fptr;
public:
    BEncoderFileOutput(File* fptr);

    void write(const char* str, Uint32 len) override;
};

/**
 * Write the output of a BEncoder to a QByteArray
 */
class KTORRENT_EXPORT BEncoderBufferOutput : public BEncoderOutput
{
    QByteArray & data;
    Uint32 ptr;
public:
    BEncoderBufferOutput(QByteArray & data);

    void write(const char* str, Uint32 len) override;
};

class KTORRENT_EXPORT BEncoderIODeviceOutput : public BEncoderOutput
{
    QIODevice* dev;
public:
    BEncoderIODeviceOutput(QIODevice* dev);

    void write(const char* str, Uint32 len) override;
};

/**
 * @author Joris Guisson
 * @brief Helper class to b-encode stuff.
 *
 * This class b-encodes data. For more details about b-encoding, see
 * the BitTorrent protocol docs. The data gets written to a BEncoderOutput
 * thing.
 */
class KTORRENT_EXPORT BEncoder
{
    BEncoderOutput* out;
    bool del;
public:
    /**
     * Constructor, output gets written to a file.
     * @param fptr The File to write to
     */
    BEncoder(File* fptr);


    /**
     * Constructor, output gets written to a BEncoderOutput object.
     * @param out The BEncoderOutput
     */
    BEncoder(BEncoderOutput* out);

    /**
    * Constructor, output gets written to a QIODevice object.
    * @param dev The QIODevice
    */
    BEncoder(QIODevice* dev);

    virtual ~BEncoder();

    /**
     * Begin a dictionary.Should have a corresponding end call.
     */
    void beginDict();

    /**
     * Begin a list. Should have a corresponding end call.
     */
    void beginList();

    template <class T>
    void write(const QByteArray& key, T val)
    {
        write(key);
        write(val);
    }

    /**
     * Write a boolean (is encoded as an intà
     * @param val
     */
    void write(bool val);

    /**
     * Write a float
     * @param val
     */
    void write(float val);

    /**
     * Write an int
     * @param val
     */
    void write(Uint32 val);

    /**
     * Write an int64
     * @param val
     */
    void write(Uint64 val);

private:
    /**
     * Write a string
     * @param str
     */
    void write(const char* str);
public:

    /**
     * Write a QByteArray
     * @param data
     */
    void write(const QByteArray & data);

    /**
     * Write a data array
     * @param data
     * @param size of data
     */
    void write(const Uint8* data, Uint32 size);

    /**
     * End a beginDict or beginList call.
     */
    void end();
};

}

#endif
