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/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/

#include <QCoreApplication>
#include <QFile>
#include <QFileInfo>
#include <QList>
#include <QNetworkAccessManager>
#include <QNetworkRequest>
#include <QNetworkReply>
#include <QStringList>
#include <QTimer>
#include <QUrl>

#include <stdio.h>

class DownloadManager: public QObject
{
    Q_OBJECT
    QNetworkAccessManager manager;
    QList<QNetworkReply *> currentDownloads;

public:
    DownloadManager();
    void doDownload(const QUrl &url);
    QString saveFileName(const QUrl &url);
    bool saveToDisk(const QString &filename, QIODevice *data);

public slots:
    void execute();
    void downloadFinished(QNetworkReply *reply);
};

DownloadManager::DownloadManager()
{
    connect(&manager, SIGNAL(finished(QNetworkReply*)),
            SLOT(downloadFinished(QNetworkReply*)));
}

void DownloadManager::doDownload(const QUrl &url)
{
    QNetworkRequest request(url);
    QNetworkReply *reply = manager.get(request);

    currentDownloads.append(reply);
}

QString DownloadManager::saveFileName(const QUrl &url)
{
    QString path = url.path();
    QString basename = QFileInfo(path).fileName();

    if (basename.isEmpty())
        basename = "download";

    if (QFile::exists(basename)) {
        // already exists, don't overwrite
        int i = 0;
        basename += '.';
        while (QFile::exists(basename + QString::number(i)))
            ++i;

        basename += QString::number(i);
    }

    return basename;
}

bool DownloadManager::saveToDisk(const QString &filename, QIODevice *data)
{
    QFile file(filename);
    if (!file.open(QIODevice::WriteOnly)) {
        fprintf(stderr, "Could not open %s for writing: %s\n",
                qPrintable(filename),
                qPrintable(file.errorString()));
        return false;
    }

    file.write(data->readAll());
    file.close();

    return true;
}

void DownloadManager::execute()
{
    QStringList args = QCoreApplication::instance()->arguments();
    args.takeFirst();           // skip the first argument, which is the program's name
    if (args.isEmpty()) {
        printf("Qt Download example - downloads all URLs in parallel\n"
               "Usage: download url1 [url2... urlN]\n"
               "\n"
               "Downloads the URLs passed in the command-line to the local directory\n"
               "If the target file already exists, a .0, .1, .2, etc. is appended to\n"
               "differentiate.\n");
        QCoreApplication::instance()->quit();
        return;
    }

    foreach (QString arg, args) {
        QUrl url = QUrl::fromEncoded(arg.toLocal8Bit());
        doDownload(url);
    }
}

void DownloadManager::downloadFinished(QNetworkReply *reply)
{
    QUrl url = reply->url();
    if (reply->error()) {
        fprintf(stderr, "Download of %s failed: %s\n",
                url.toEncoded().constData(),
                qPrintable(reply->errorString()));
    else {
        QString filename = saveFileName(url);
        if (saveToDisk(filename, reply))
            printf("Download of %s succeded (saved to %s)\n",
                   url.toEncoded().constData(), qPrintable(filename));
    }

    currentDownloads.removeAll(reply);
    reply->deleteLater();

    if (currentDownloads.isEmpty())
        // all downloads finished
        QCoreApplication::instance()->quit();
}

int main(int argc, char **argv)
{
    QCoreApplication app(argc, argv);

    DownloadManager manager;
    QTimer::singleShot(0, &manager, SLOT(execute()));

    app.exec();
}

#include "main.moc"

   
    
  
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