annotate data/fileio/RemoteFile.h @ 316:3a6725f285d6

* Make RemoteFile far more pervasive, and use it for local files as well
  so that we can handle both transparently.  Make it shallow copy with
  reference counting, so it can be used by value without having to worry
  about the cache file lifetime.  Use RemoteFile for MainWindow file-open
  functions, etc

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    This file copyright 2007 QMUL.
    
    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.  See the file
    COPYING included with this distribution for more information.
*/

#ifndef _REMOTE_FILE_H_
#define _REMOTE_FILE_H_

#include <QUrl>
#include <QMutex>
#include <QString>
#include <QTimer>

#include <map>

class QFtp;
class QHttp;
class QFile;
class QProgressDialog;
class QHttpResponseHeader;

class RemoteFile : public QObject
{
    Q_OBJECT

public:
    RemoteFile(QString fileOrUrl, bool showProgress = true);
    RemoteFile(QUrl url, bool showProgress = true);
    RemoteFile(const RemoteFile &);

    virtual ~RemoteFile();

    bool isAvailable();

    void waitForStatus();
    void waitForData();

    void setLeaveLocalFile(bool leave);

    bool isOK() const;
    bool isDone() const;
    bool isRemote() const;

    QString getLocation() const;
    QString getLocalFilename() const;
    QString getContentType() const;
    QString getExtension() const;

    QString getErrorString() const;

    static bool isRemote(QString fileOrUrl);
    static bool canHandleScheme(QUrl url);

signals:
    void progress(int percent);
    void ready();

protected slots:
    void dataReadProgress(int done, int total);
    void httpResponseHeaderReceived(const QHttpResponseHeader &resp);
    void ftpCommandFinished(int, bool);
    void dataTransferProgress(qint64 done, qint64 total);
    void done(bool error);
    void showProgressDialog();
    void cancelled();

protected:
    RemoteFile &operator=(const RemoteFile &); // not provided

    QUrl m_url;
    QFtp *m_ftp;
    QHttp *m_http;
    QFile *m_localFile;
    QString m_localFilename;
    QString m_errorString;
    QString m_contentType;
    bool m_ok;
    int m_lastStatus;
    bool m_remote;
    bool m_done;
    bool m_leaveLocalFile;
    QProgressDialog *m_progressDialog;
    QTimer m_progressShowTimer;

    typedef std::map<QUrl, int> RemoteRefCountMap;
    typedef std::map<QUrl, QString> RemoteLocalMap;
    static RemoteRefCountMap m_refCountMap;
    static RemoteLocalMap m_remoteLocalMap;
    static QMutex m_mapMutex;
    bool m_refCounted;

    void init(bool showProgress);
    void initHttp();
    void initFtp();

    void cleanup();

    // Create a local file for m_url.  If it already existed, return true.
    // The local filename is stored in m_localFilename.
    bool createCacheFile();
    void deleteCacheFile();

    static QMutex m_fileCreationMutex;
    static int m_count;
};

#endif