/*
 * Copyright (C) by Olivier Goffart <ogoffart@owncloud.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.
 */

#ifndef OWNCLOUDPROPAGATOR_H
#define OWNCLOUDPROPAGATOR_H

#include <neon/ne_request.h>
#include <QHash>
#include <QObject>
#include <qelapsedtimer.h>

#include "syncfileitem.h"
#include "progressdispatcher.h"

struct hbf_transfer_s;
struct ne_session_s;
struct ne_decompress_s;

namespace Mirall {

class SyncJournalDb;
class OwncloudPropagator;

class PropagatorJob : public QObject {
    Q_OBJECT
protected:
    OwncloudPropagator *_propagator;
public:
    explicit PropagatorJob(OwncloudPropagator* propagator) : _propagator(propagator) {}

public slots:
    virtual void start() = 0;
signals:
    void finished(SyncFileItem::Status);
    void completed(const SyncFileItem &);
    void progress(Progress::Kind, const SyncFileItem& item, quint64 bytes, quint64 total);
};

/*
 * Propagate a directory, and all its sub entries.
 */
class PropagateDirectory : public PropagatorJob {
    Q_OBJECT
public:
    // e.g: create the directory
    QScopedPointer<PropagatorJob>_firstJob;

    // all the sub files or sub directories.
    //TODO:  in the future, all sub job can be run in parallel
    QVector<PropagatorJob *> _subJobs;

    SyncFileItem _item;

    int _current; // index of the current running job
    SyncFileItem::Status _hasError;  // NoStatus,  or NormalError / SoftError if there was an error


    explicit PropagateDirectory(OwncloudPropagator *propagator, const SyncFileItem &item = SyncFileItem())
        : PropagatorJob(propagator)
        , _firstJob(0), _item(item),  _current(-1), _hasError(SyncFileItem::NoStatus) { }

    virtual ~PropagateDirectory() {
        qDeleteAll(_subJobs);
    }

    void append(PropagatorJob *subJob) {
        _subJobs.append(subJob);
    }

    virtual void start();


private slots:
    void startJob(PropagatorJob *next) {
        connect(next, SIGNAL(finished(SyncFileItem::Status)), this, SLOT(proceedNext(SyncFileItem::Status)), Qt::QueuedConnection);
        connect(next, SIGNAL(completed(SyncFileItem)), this, SIGNAL(completed(SyncFileItem)));
        connect(next, SIGNAL(progress(Progress::Kind,SyncFileItem,quint64,quint64)), this, SIGNAL(progress(Progress::Kind,SyncFileItem,quint64,quint64)));
        next->start();
    }

    void proceedNext(SyncFileItem::Status status);
};


/*
 * Abstract class to propagate a single item
 */
class PropagateItemJob : public PropagatorJob {
    Q_OBJECT
protected:
    void done(SyncFileItem::Status status, const QString &errorString = QString());

    void updateMTimeAndETag(const char *uri, time_t);

    /* fetch the error code and string from the session
       in case of error, calls done with the error and returns true.

       If the HTTP error code is ignoreHTTPError,  the error is ignored
     */
    bool updateErrorFromSession(int neon_code = 0, ne_request *req = 0, int ignoreHTTPError = 0);

    /*
     * to be called by the progress callback and will wait the amount of time needed.
     */
    void limitBandwidth(qint64 progress, qint64 limit);

    QElapsedTimer _lastTime;
    qint64        _lastProgress;
    int           _httpStatusCode;
    SyncFileItem  _item;

public:
    PropagateItemJob(OwncloudPropagator* propagator, const SyncFileItem &item)
        : PropagatorJob(propagator), _lastProgress(0), _httpStatusCode(0), _item(item) {}
};

// Dummy job that just mark it as completed and ignored.
class PropagateIgnoreJob : public PropagateItemJob {
    Q_OBJECT
public:
    PropagateIgnoreJob(OwncloudPropagator* propagator,const SyncFileItem& item)
        : PropagateItemJob(propagator, item) {}
    void start() {
        done(SyncFileItem::FileIgnored);
    }
};


class OwncloudPropagator : public QObject {
    Q_OBJECT

    PropagateItemJob *createJob(const SyncFileItem& item);
    QScopedPointer<PropagateDirectory> _rootJob;

public:
    ne_session_s *_session;
    QString _localDir; // absolute path to the local directory. ends with '/'
    QString _remoteDir; // path to the root of the remote. ends with '/'
    SyncJournalDb *_journal;

public:
    OwncloudPropagator(ne_session_s *session, const QString &localDir, const QString &remoteDir,
                       SyncJournalDb *progressDb, QAtomicInt *abortRequested)
            : _session(session)
            , _localDir(localDir)
            , _remoteDir(remoteDir)
            , _journal(progressDb)
            , _abortRequested(abortRequested)
    {
        if (!localDir.endsWith(QChar('/'))) _localDir+='/';
        if (!remoteDir.endsWith(QChar('/'))) _remoteDir+='/';
    }

    void start(const SyncFileItemVector &_syncedItems);

    int _downloadLimit;
    int _uploadLimit;

    QAtomicInt *_abortRequested; // boolean set by the main thread to abort.

    void overallTransmissionSizeChanged( qint64 change );

signals:
    void completed(const SyncFileItem &);
    void progress(Progress::Kind kind, const SyncFileItem&, quint64 bytes, quint64 total);
    void progressChanged(qint64 change);
    void finished();

};

}

#endif