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#ifndef TORRENTCLIENT_H

#define TORRENTCLIENT_H

#include <QBitArray>

#include <QHostAddress>

#include <QList>

class MetaInfo;

class PeerWireClient;

class TorrentClientPrivate;

class TorrentPeer;

class TorrentPiece;

QT_BEGIN_NAMESPACE

class QTimerEvent;

QT_END_NAMESPACE

class TorrentPeer {

public:

    QHostAddress address;

    quint16 port;

    QString id;

    bool interesting;

    bool seed;

    uint lastVisited;

    uint connectStart;

    uint connectTime;

    QBitArray pieces;

    int numCompletedPieces;

    inline bool operator==(const TorrentPeer &other)

    {

        return port == other.port

            && address == other.address

            && id == other.id;

    }

};

class TorrentClient : public QObject

{

    Q_OBJECT

public:

    enum State {

        Idle,

        Paused,

        Stopping,

        Preparing,

        Searching,

        Connecting,

        WarmingUp,

        Downloading,

        Endgame,

        Seeding

    };

    enum Error {

        UnknownError,

        TorrentParseError,

        InvalidTrackerError,

        FileError,

        ServerError

    };

    TorrentClient(QObject *parent = 0);

    ~TorrentClient();

    bool setTorrent(const QString &fileName);

    bool setTorrent(const QByteArray &torrentData);

    MetaInfo metaInfo() const;

    void setMaxConnections(int connections);

    int maxConnections() const;

    void setDestinationFolder(const QString &directory);

    QString destinationFolder() const;

    void setDumpedState(const QByteArray &dumpedState);

    QByteArray dumpedState() const;

    // Progress and stats for download feedback.

    qint64 progress() const;

    void setDownloadedBytes(qint64 bytes);

    qint64 downloadedBytes() const;

    void setUploadedBytes(qint64 bytes);

    qint64 uploadedBytes() const;

    int connectedPeerCount() const;

    int seedCount() const;

    // Accessors for the tracker

    QByteArray peerId() const;

    QByteArray infoHash() const;

    quint16 serverPort() const;

    // State and error.

    State state() const;

    QString stateString() const;

    Error error() const;

    QString errorString() const;

signals:

    void stateChanged(TorrentClient::State state);

    void error(TorrentClient::Error error);

    void downloadCompleted();

    void peerInfoUpdated();

    void dataSent(int uploadedBytes);

    void dataReceived(int downloadedBytes);

    void progressUpdated(int percentProgress);

    void downloadRateUpdated(int bytesPerSecond);

    void uploadRateUpdated(int bytesPerSecond);

    void stopped();

public slots:

    void start();

    void stop();

    void setPaused(bool paused);

    void setupIncomingConnection(PeerWireClient *client);

protected slots:

    void timerEvent(QTimerEvent *event);

private slots:

    // File management

    void sendToPeer(int readId, int pieceIndex, int begin, const QByteArray &data);

    void fullVerificationDone();

    void pieceVerified(int pieceIndex, bool ok);

    void handleFileError();

    // Connection handling

    void connectToPeers();

    QList<TorrentPeer *> weighedFreePeers() const;

    void setupOutgoingConnection();

    void initializeConnection(PeerWireClient *client);

    void removeClient();

    void peerPiecesAvailable(const QBitArray &pieces);

    void peerRequestsBlock(int pieceIndex, int begin, int length);

    void blockReceived(int pieceIndex, int begin, const QByteArray &data);

    void peerWireBytesWritten(qint64 bytes);

    void peerWireBytesReceived(qint64 bytes);

    int blocksLeftForPiece(const TorrentPiece *piece) const;

    // Scheduling

    void scheduleUploads();

    void scheduleDownloads();

    void schedulePieceForClient(PeerWireClient *client);

    void requestMore(PeerWireClient *client);

    int requestBlocks(PeerWireClient *client, TorrentPiece *piece, int maxBlocks);

    void peerChoked();

    void peerUnchoked();

    // Tracker handling

    void addToPeerList(const QList<TorrentPeer> &peerList);

    void trackerStopped();

    // Progress

    void updateProgress(int progress = -1);

private:

    TorrentClientPrivate *d;

    friend class TorrentClientPrivate;

};

#endif