/**************************************************************************
**
** This file is part of Qt SDK**
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** Copyright (c) 2011 Nokia Corporation and/or its subsidiary(-ies).*
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** No Commercial Usage
**
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
**
** 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:
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**
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** rights. These rights are described in the Nokia Qt LGPL Exception version
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**************************************************************************/
#include "extractarchiveoperation.h"
#include "extractarchiveoperation_p.h"

#include <QtCore/QEventLoop>
#include <QtCore/QThread>
#include <QtCore/QThreadPool>

using namespace QInstaller;


ExtractArchiveOperation::ExtractArchiveOperation()
{
    setName(QLatin1String("Extract"));
}

ExtractArchiveOperation::~ExtractArchiveOperation()
{
}

void ExtractArchiveOperation::backup()
{
    // we need to backup on the fly...
}

bool ExtractArchiveOperation::performOperation()
{
    const QStringList args = arguments();
    if (args.count() != 2) {
        setError(InvalidArguments);
        setErrorString(tr("Invalid arguments in %0: %1 arguments given, 2 expected.").arg(name()).arg(args
            .count()));
        return false;
    }

    const QString archivePath = args.first();
    const QString targetDir = args.at(1);

    Receiver receiver;
    Callback callback;

    // usually we have to connect it as queued connection but then some blocking work is in the main thread
    connect(&callback, SIGNAL(progressChanged(QString)), this, SLOT(slotProgressChanged(QString)),
        Qt::DirectConnection);

    if (PackageManagerCore *core = this->value(QLatin1String("installer")).value<PackageManagerCore*>()) {
        connect(core, SIGNAL(statusChanged(QInstaller::PackageManagerCore::Status)), &callback,
            SLOT(statusChanged(QInstaller::PackageManagerCore::Status)), Qt::QueuedConnection);
    }

    //Runnable is derived from QRunable which will be deleted by the ThreadPool -> no parent is needed
    Runnable *runnable = new Runnable(archivePath, targetDir, &callback);
    connect(runnable, SIGNAL(finished(bool,QString)), &receiver, SLOT(runnableFinished(bool,QString)),
        Qt::QueuedConnection);

    QEventLoop loop;
    connect(&receiver, SIGNAL(finished()), &loop, SLOT(quit()));
    if (QThreadPool::globalInstance()->tryStart(runnable)) {
        loop.exec();
    } else {
        // in case there is no availabe thread we should call it directly this is more a hack
        runnable->run();
        receiver.runnableFinished(true, QString());
    }

    typedef QPair<QString, QString> StringPair;
    QVector<StringPair> backupFiles = callback.backupFiles;

    //TODO use backups for rollback, too? doesn't work for uninstallation though

    //delete all backups we can delete right now, remember the rest
    foreach (const StringPair &i, backupFiles)
        deleteFileNowOrLater(i.second);

    if (!receiver.success) {
        setError(UserDefinedError);
        setErrorString(receiver.errorString);
        return false;
    }
    return true;
}

bool ExtractArchiveOperation::undoOperation()
{
    Q_ASSERT(arguments().count() == 2);
    //const QString archivePath = arguments().first();
    //const QString targetDir = arguments().last();

    const QStringList files = value(QLatin1String("files")).toStringList();

    WorkerThread *const thread = new WorkerThread(this, files);
    connect(thread, SIGNAL(outputTextChanged(QString)), this, SIGNAL(outputTextChanged(QString)),
        Qt::QueuedConnection);

    QEventLoop loop;
    connect(thread, SIGNAL(finished()), &loop, SLOT(quit()), Qt::QueuedConnection);
    thread->start();
    loop.exec();
    thread->deleteLater();
    return true;
}

bool ExtractArchiveOperation::testOperation()
{
    return true;
}

Operation *ExtractArchiveOperation::clone() const
{
    return new ExtractArchiveOperation();
}

/*!
    This slot is direct connected to the caller so please don't call it from another thread in the same time.
*/
void ExtractArchiveOperation::slotProgressChanged(const QString &filename)
{
    QStringList files = value(QLatin1String("files")).toStringList();
    files.prepend(filename);
    setValue(QLatin1String("files"), files);
    emit outputTextChanged(filename);
}