/**************************************************************************
**
** Copyright (C) 2012-2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the Qt Installer Framework.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia.  For licensing terms and
** conditions see http://qt.digia.com/licensing.  For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** 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, Digia gives you certain additional
** rights.  These rights are described in the Digia 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.
**
**
** $QT_END_LICENSE$
**
**************************************************************************/
#include "downloadarchivesjob.h"

#include "binaryformatenginehandler.h"
#include "component.h"
#include "messageboxhandler.h"
#include "packagemanagercore.h"
#include "utils.h"

#include "kdupdaterfiledownloader.h"
#include "kdupdaterfiledownloaderfactory.h"

#include <QtCore/QFile>
#include <QtCore/QTimerEvent>

using namespace QInstaller;
using namespace KDUpdater;


/*!
    Creates a new DownloadArchivesJob with \a parent.
*/
DownloadArchivesJob::DownloadArchivesJob(PackageManagerCore *core)
    : KDJob(core),
      m_core(core),
      m_downloader(0),
      m_archivesDownloaded(0),
      m_archivesToDownloadCount(0),
      m_canceled(false),
      m_lastFileProgress(0),
      m_progressChangedTimerId(0)
{
    setCapabilities(Cancelable);
}

/*!
    Destroys the DownloadArchivesJob.
    All temporary files get deleted.
*/
DownloadArchivesJob::~DownloadArchivesJob()
{
    foreach (const QString &fileName, m_temporaryFiles) {
        QFile file(fileName);
        if (file.exists() && !file.remove())
            qWarning("Could not delete file %s: %s", qPrintable(fileName), qPrintable(file.errorString()));
    }

    if (m_downloader)
        m_downloader->deleteLater();
}

/*!
    Sets the archives to download. The first value of each pair contains the file name to register
    the file in the installer's internal file system, the second one the source url.
*/
void DownloadArchivesJob::setArchivesToDownload(const QList<QPair<QString, QString> > &archives)
{
    m_archivesToDownload = archives;
    m_archivesToDownloadCount = archives.count();
}

/*!
    \reimp
*/
void DownloadArchivesJob::doStart()
{
    m_archivesDownloaded = 0;
    fetchNextArchiveHash();
}

/*!
    \reimp
*/
void DownloadArchivesJob::doCancel()
{
    m_canceled = true;
    if (m_downloader != 0)
        m_downloader->cancelDownload();
}

void DownloadArchivesJob::fetchNextArchiveHash()
{
    if (m_core->testChecksum()) {
        if (m_canceled) {
            finishWithError(tr("Canceled"));
            return;
        }

        if (m_archivesToDownload.isEmpty()) {
            emitFinished();
            return;
        }

        if (m_downloader)
            m_downloader->deleteLater();

        m_downloader = setupDownloader(QLatin1String(".sha1"));
        if (!m_downloader) {
            m_archivesToDownload.removeFirst();
            QMetaObject::invokeMethod(this, "fetchNextArchiveHash", Qt::QueuedConnection);
            return;
        }

        connect(m_downloader, SIGNAL(downloadCompleted()), this, SLOT(finishedHashDownload()),
            Qt::QueuedConnection);
        m_downloader->download();
    } else {
        QMetaObject::invokeMethod(this, "fetchNextArchive", Qt::QueuedConnection);
    }
}

void DownloadArchivesJob::finishedHashDownload()
{
    Q_ASSERT(m_downloader != 0);

    const QString tempFile = m_downloader->downloadedFileName();
    QFile sha1HashFile(tempFile);
    if (sha1HashFile.open(QFile::ReadOnly))
        m_currentHash = sha1HashFile.readAll();
    else
        finishWithError(tr("Downloading hash signature failed."));

    m_temporaryFiles.insert(tempFile);

    fetchNextArchive();
}

/*!
    Fetches the next archive and registers it in the installer.
*/
void DownloadArchivesJob::fetchNextArchive()
{
    if (m_canceled) {
        finishWithError(tr("Canceled"));
        return;
    }

    if (m_archivesToDownload.isEmpty()) {
        emitFinished();
        return;
    }

    if (m_downloader != 0)
        m_downloader->deleteLater();

    m_downloader = setupDownloader();
    if (!m_downloader) {
        m_archivesToDownload.removeFirst();
        QMetaObject::invokeMethod(this, "fetchNextArchive", Qt::QueuedConnection);
        return;
    }

    emit progressChanged(double(m_archivesDownloaded) / m_archivesToDownloadCount);
    connect(m_downloader, SIGNAL(downloadProgress(double)), this, SLOT(emitDownloadProgress(double)));
    connect(m_downloader, SIGNAL(downloadCompleted()), this, SLOT(registerFile()), Qt::QueuedConnection);

    m_downloader->download();
}

/*!
    Emits the global download progress during a single download in a lazy way (uses a timer to reduce to
    much processChanged).
*/
void DownloadArchivesJob::emitDownloadProgress(double progress)
{
    m_lastFileProgress = progress;
    if (!m_progressChangedTimerId)
        m_progressChangedTimerId = startTimer(5);
}

/*!
    This is used to reduce the progressChanged signals.
*/
void DownloadArchivesJob::timerEvent(QTimerEvent *event)
{
    if (event->timerId() == m_progressChangedTimerId) {
        killTimer(m_progressChangedTimerId);
        m_progressChangedTimerId = 0;
        emit progressChanged((double(m_archivesDownloaded) + m_lastFileProgress) / m_archivesToDownloadCount);
    }
}

/*!
    Registers the just downloaded file in the installer's file system.
*/
void DownloadArchivesJob::registerFile()
{
    Q_ASSERT(m_downloader != 0);

    if (m_canceled)
        return;

    if (m_core->testChecksum() && m_currentHash != m_downloader->sha1Sum().toHex()) {
        //TODO: Maybe we should try to download the file again automatically
        const QMessageBox::Button res =
            MessageBoxHandler::critical(MessageBoxHandler::currentBestSuitParent(),
            QLatin1String("DownloadError"), tr("Download Error"), tr("Hash verification while "
            "downloading failed. This is a temporary error, please retry."),
            QMessageBox::Retry | QMessageBox::Cancel, QMessageBox::Cancel);

        if (res == QMessageBox::Cancel) {
            finishWithError(tr("Could not verify Hash"));
            return;
        }

        fetchNextArchiveHash();
        return;
    }

    ++m_archivesDownloaded;
    if (m_progressChangedTimerId) {
        killTimer(m_progressChangedTimerId);
        m_progressChangedTimerId = 0;
        emit progressChanged(double(m_archivesDownloaded) / m_archivesToDownloadCount);
    }

    m_temporaryFiles.insert(m_downloader->downloadedFileName());
    const QPair<QString, QString> pair = m_archivesToDownload.takeFirst();
    QInstallerCreator::BinaryFormatEngineHandler::instance()->registerArchive(pair.first,
        m_downloader->downloadedFileName());

    fetchNextArchiveHash();
}

void DownloadArchivesJob::downloadCanceled()
{
    emitFinishedWithError(KDJob::Canceled, m_downloader->errorString());
}

void DownloadArchivesJob::downloadFailed(const QString &error)
{
    if (m_canceled)
        return;

    const QMessageBox::StandardButton b =
        MessageBoxHandler::critical(MessageBoxHandler::currentBestSuitParent(),
        QLatin1String("archiveDownloadError"), tr("Download Error"), tr("Could not download archive: %1 : %2")
        .arg(m_archivesToDownload.first().second, error), QMessageBox::Retry | QMessageBox::Cancel);

    if (b == QMessageBox::Retry)
        QMetaObject::invokeMethod(this, "fetchNextArchiveHash", Qt::QueuedConnection);
    else
        downloadCanceled();
}

void DownloadArchivesJob::finishWithError(const QString &error)
{
    const FileDownloader *const dl = dynamic_cast<const FileDownloader*> (sender());
    const QString msg = tr("Could not fetch archives: %1\nError while loading %2");
    if (dl != 0)
        emitFinishedWithError(QInstaller::DownloadError, msg.arg(error, dl->url().toString()));
    else
        emitFinishedWithError(QInstaller::DownloadError, msg.arg(error, m_downloader->url().toString()));
}

KDUpdater::FileDownloader *DownloadArchivesJob::setupDownloader(const QString &suffix)
{
    KDUpdater::FileDownloader *downloader = 0;
    const QFileInfo fi = QFileInfo(m_archivesToDownload.first().first);
    const Component *const component = m_core->componentByName(QFileInfo(fi.path()).fileName());
    if (component) {
        const QUrl url(m_archivesToDownload.first().second + suffix);
        const QString &scheme = url.scheme();
        downloader = FileDownloaderFactory::instance().create(scheme, this);

        if (downloader) {
            downloader->setUrl(url);
            downloader->setAutoRemoveDownloadedFile(false);

            QAuthenticator auth;
            auth.setUser(component->value(QLatin1String("username")));
            auth.setPassword(component->value(QLatin1String("password")));
            downloader->setAuthenticator(auth);

            connect(downloader, SIGNAL(downloadCanceled()), this, SLOT(downloadCanceled()));
            connect(downloader, SIGNAL(downloadAborted(QString)), this, SLOT(downloadFailed(QString)),
                Qt::QueuedConnection);
            connect(downloader, SIGNAL(downloadStatus(QString)), this, SIGNAL(downloadStatusChanged(QString)));

            if (scheme == QLatin1String("http") || scheme == QLatin1String("ftp") ||
                scheme == QLatin1String("file")) {
                    downloader->setDownloadedFileName(component->localTempPath() + QLatin1String("/")
                        + component->name() + QLatin1String("/") + fi.fileName() + suffix);
            }

            QString message = tr("Downloading archive hash for component: %1");
            if (suffix.isEmpty())
                message = tr("Downloading archive for component: %1");
            emit outputTextChanged(message.arg(component->displayName()));
        } else {
            emit outputTextChanged(tr("Scheme not supported: %1 (%2)").arg(scheme, url.toString()));
        }
    } else {
        emit outputTextChanged(tr("Could not find component for: %1.").arg(QFileInfo(fi.path()).fileName()));
    }
    return downloader;
}