/****************************************************************************

**

** All rights reserved.

** Contact: Nokia Corporation (qt-info@nokia.com)

**

** This file is part of the demonstration applications of the Qt Toolkit.

**

** $QT_BEGIN_LICENSE:LGPL$

** 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

** 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.

**

** If you have questions regarding the use of this file, please contact

** Nokia at qt-info@nokia.com.

**

**

**

**

**

**

**

**

** $QT_END_LICENSE$

**

****************************************************************************/

#include "downloadmanager.h"

#include "autosaver.h"

#include "browserapplication.h"

#include "networkaccessmanager.h"

#include <math.h>

#include <QtCore/QMetaEnum>

#include <QtCore/QSettings>

#include <QtGui/QDesktopServices>

#include <QtGui/QFileDialog>

#include <QtGui/QHeaderView>

#include <QtGui/QFileIconProvider>

#include <QtCore/QDebug>

#include <QtWebKit/QWebSettings>

/*!

    DownloadItem is a widget that is displayed in the download manager list.

    It moves the data from the QNetworkReply into the QFile as well

    as update the information/progressbar and report errors.

 */

DownloadItem::DownloadItem(QNetworkReply *reply, bool requestFileName, QWidget *parent)

    : QWidget(parent)

    , m_reply(reply)

    , m_requestFileName(requestFileName)

    , m_bytesReceived(0)

{

    setupUi(this);

    QPalette p = downloadInfoLabel->palette();

    p.setColor(QPalette::Text, Qt::darkGray);

    downloadInfoLabel->setPalette(p);

    progressBar->setMaximum(0);

    tryAgainButton->hide();

    connect(stopButton, SIGNAL(clicked()), this, SLOT(stop()));

    connect(openButton, SIGNAL(clicked()), this, SLOT(open()));

    connect(tryAgainButton, SIGNAL(clicked()), this, SLOT(tryAgain()));

    init();

}

void DownloadItem::init()

{

    if (!m_reply)

        return;

    // attach to the m_reply

    m_url = m_reply->url();

    m_reply->setParent(this);

    connect(m_reply, SIGNAL(readyRead()), this, SLOT(downloadReadyRead()));

    connect(m_reply, SIGNAL(error(QNetworkReply::NetworkError)),

            this, SLOT(error(QNetworkReply::NetworkError)));

    connect(m_reply, SIGNAL(downloadProgress(qint64,qint64)),

            this, SLOT(downloadProgress(qint64,qint64)));

    connect(m_reply, SIGNAL(metaDataChanged()),

            this, SLOT(metaDataChanged()));

    connect(m_reply, SIGNAL(finished()),

            this, SLOT(finished()));

    // reset info

    downloadInfoLabel->clear();

    progressBar->setValue(0);

    getFileName();

    // start timer for the download estimation

    m_downloadTime.start();

    if (m_reply->error() != QNetworkReply::NoError) {

        error(m_reply->error());

        finished();

    }

}

void DownloadItem::getFileName()

{

    QSettings settings;

    settings.beginGroup(QLatin1String("downloadmanager"));

    QString defaultLocation = QDesktopServices::storageLocation(QDesktopServices::DesktopLocation);

    QString downloadDirectory = settings.value(QLatin1String("downloadDirectory"), defaultLocation).toString();

    if (!downloadDirectory.isEmpty())

        downloadDirectory += QLatin1Char('/');

    QString defaultFileName = saveFileName(downloadDirectory);

    QString fileName = defaultFileName;

    if (m_requestFileName) {

        fileName = QFileDialog::getSaveFileName(this, tr("Save File"), defaultFileName);

        if (fileName.isEmpty()) {

            m_reply->close();

            fileNameLabel->setText(tr("Download canceled: %1").arg(QFileInfo(defaultFileName).fileName()));

            return;

        }

    }

    m_output.setFileName(fileName);

    fileNameLabel->setText(QFileInfo(m_output.fileName()).fileName());

    if (m_requestFileName)

        downloadReadyRead();

}

QString DownloadItem::saveFileName(const QString &directory) const

{

    // Move this function into QNetworkReply to also get file name sent from the server

    QString path = m_url.path();

    QFileInfo info(path);

    QString baseName = info.completeBaseName();

    QString endName = info.suffix();

    if (baseName.isEmpty()) {

        baseName = QLatin1String("unnamed_download");

        qDebug() << "DownloadManager:: downloading unknown file:" << m_url;

    }

    QString name = directory + baseName + QLatin1Char('.') + endName;

    if (QFile::exists(name)) {

        // already exists, don't overwrite

        int i = 1;

        do {

            name = directory + baseName + QLatin1Char('-') + QString::number(i++) + QLatin1Char('.') + endName;

        } while (QFile::exists(name));

    }

    return name;

}

void DownloadItem::stop()

{

    setUpdatesEnabled(false);

    stopButton->setEnabled(false);

    stopButton->hide();

    tryAgainButton->setEnabled(true);

    tryAgainButton->show();

    setUpdatesEnabled(true);

    m_reply->abort();

}

void DownloadItem::open()

{

    QFileInfo info(m_output);

    QUrl url = QUrl::fromLocalFile(info.absolutePath());

    QDesktopServices::openUrl(url);

}

void DownloadItem::tryAgain()

{

    if (!tryAgainButton->isEnabled())

        return;

    tryAgainButton->setEnabled(false);

    tryAgainButton->setVisible(false);

    stopButton->setEnabled(true);

    stopButton->setVisible(true);

    progressBar->setVisible(true);

    QNetworkReply *r = BrowserApplication::networkAccessManager()->get(QNetworkRequest(m_url));

    if (m_reply)

        m_reply->deleteLater();

    if (m_output.exists())

        m_output.remove();

    m_reply = r;

    init();

    emit statusChanged();

}

void DownloadItem::downloadReadyRead()

{

    if (m_requestFileName && m_output.fileName().isEmpty())

        return;

    if (!m_output.isOpen()) {

        // in case someone else has already put a file there

        if (!m_requestFileName)

            getFileName();

        if (!m_output.open(QIODevice::WriteOnly)) {

            downloadInfoLabel->setText(tr("Error opening save file: %1")

                    .arg(m_output.errorString()));

            stopButton->click();

            emit statusChanged();

            return;

        }

        emit statusChanged();

    }

    if (-1 == m_output.write(m_reply->readAll())) {

        downloadInfoLabel->setText(tr("Error saving: %1")

                .arg(m_output.errorString()));

        stopButton->click();

    }

}

void DownloadItem::error(QNetworkReply::NetworkError)

{

    qDebug() << "DownloadItem::error" << m_reply->errorString() << m_url;

    downloadInfoLabel->setText(tr("Network Error: %1").arg(m_reply->errorString()));

    tryAgainButton->setEnabled(true);

    tryAgainButton->setVisible(true);

}

void DownloadItem::metaDataChanged()

{

    qDebug() << "DownloadItem::metaDataChanged: not handled.";

}

void DownloadItem::downloadProgress(qint64 bytesReceived, qint64 bytesTotal)

{

    m_bytesReceived = bytesReceived;

    if (bytesTotal == -1) {

        progressBar->setValue(0);

        progressBar->setMaximum(0);

    } else {

        progressBar->setValue(bytesReceived);

        progressBar->setMaximum(bytesTotal);

    }

    updateInfoLabel();

}

void DownloadItem::updateInfoLabel()

{

    if (m_reply->error() == QNetworkReply::NoError)

        return;

    qint64 bytesTotal = progressBar->maximum();

    bool running = !downloadedSuccessfully();

    // update info label

    double speed = m_bytesReceived * 1000.0 / m_downloadTime.elapsed();

    double timeRemaining = ((double)(bytesTotal - m_bytesReceived)) / speed;

    QString timeRemainingString = tr("seconds");

    if (timeRemaining > 60) {

        timeRemaining = timeRemaining / 60;

        timeRemainingString = tr("minutes");

    }

    timeRemaining = floor(timeRemaining);

    // When downloading the eta should never be 0

    if (timeRemaining == 0)

        timeRemaining = 1;

    QString info;

    if (running) {

        QString remaining;

        if (bytesTotal != 0)

            remaining = tr("- %4 %5 remaining")

            .arg(timeRemaining)

            .arg(timeRemainingString);

        info = QString(tr("%1 of %2 (%3/sec) %4"))

            .arg(dataString(m_bytesReceived))

            .arg(bytesTotal == 0 ? tr("?") : dataString(bytesTotal))

            .arg(dataString((int)speed))

            .arg(remaining);

    } else {

        if (m_bytesReceived == bytesTotal)

            info = dataString(m_output.size());

        else

            info = tr("%1 of %2 - Stopped")

                .arg(dataString(m_bytesReceived))

                .arg(dataString(bytesTotal));

    }

    downloadInfoLabel->setText(info);

}

QString DownloadItem::dataString(int size) const

{

    QString unit;

    if (size < 1024) {

        unit = tr("bytes");

    } else if (size < 1024*1024) {

        size /= 1024;

        unit = tr("kB");

    } else {

        size /= 1024*1024;

        unit = tr("MB");

    }

    return QString(QLatin1String("%1 %2")).arg(size).arg(unit);

}

bool DownloadItem::downloading() const

{

    return (progressBar->isVisible());

}

bool DownloadItem::downloadedSuccessfully() const

{

    return (stopButton->isHidden() && tryAgainButton->isHidden());

}

void DownloadItem::finished()

{

    progressBar->hide();

    stopButton->setEnabled(false);

    stopButton->hide();

    m_output.close();

    updateInfoLabel();

    emit statusChanged();

}

/*!

    DownloadManager is a Dialog that contains a list of DownloadItems

    It is a basic download manager.  It only downloads the file, doesn't do BitTorrent,

    extract zipped files or anything fancy.

  */

DownloadManager::DownloadManager(QWidget *parent)

    : QDialog(parent)

    , m_autoSaver(new AutoSaver(this))

    , m_manager(BrowserApplication::networkAccessManager())

    , m_iconProvider(0)

    , m_removePolicy(Never)

{

    setupUi(this);

    downloadsView->setShowGrid(false);

    downloadsView->verticalHeader()->hide();

    downloadsView->horizontalHeader()->hide();

    downloadsView->setAlternatingRowColors(true);

    downloadsView->horizontalHeader()->setStretchLastSection(true);

    m_model = new DownloadModel(this);

    downloadsView->setModel(m_model);

    connect(cleanupButton, SIGNAL(clicked()), this, SLOT(cleanup()));

    load();

}

DownloadManager::~DownloadManager()

{

    m_autoSaver->changeOccurred();

    m_autoSaver->saveIfNeccessary();

    if (m_iconProvider)

        delete m_iconProvider;

}

int DownloadManager::activeDownloads() const

{

    int count = 0;

    for (int i = 0; i < m_downloads.count(); ++i) {

        if (m_downloads.at(i)->stopButton->isEnabled())

            ++count;

    }

    return count;

}

void DownloadManager::download(const QNetworkRequest &request, bool requestFileName)

{

    if (request.url().isEmpty())

        return;

    handleUnsupportedContent(m_manager->get(request), requestFileName);

}

void DownloadManager::handleUnsupportedContent(QNetworkReply *reply, bool requestFileName)

{

    if (!reply || reply->url().isEmpty())

        return;

    QVariant header = reply->header(QNetworkRequest::ContentLengthHeader);

    bool ok;

    int size = header.toInt(&ok);

    if (ok && size == 0)

        return;

    qDebug() << "DownloadManager::handleUnsupportedContent" << reply->url() << "requestFileName" << requestFileName;

    DownloadItem *item = new DownloadItem(reply, requestFileName, this);

    addItem(item);

}

void DownloadManager::addItem(DownloadItem *item)

{

    connect(item, SIGNAL(statusChanged()), this, SLOT(updateRow()));

    int row = m_downloads.count();

    m_model->beginInsertRows(QModelIndex(), row, row);

    m_downloads.append(item);

    m_model->endInsertRows();

    updateItemCount();

    if (row == 0)

        show();

    downloadsView->setIndexWidget(m_model->index(row, 0), item);

    QIcon icon = style()->standardIcon(QStyle::SP_FileIcon);

    item->fileIcon->setPixmap(icon.pixmap(48, 48));

    downloadsView->setRowHeight(row, item->sizeHint().height());

}

void DownloadManager::updateRow()

{

    DownloadItem *item = qobject_cast<DownloadItem*>(sender());

    int row = m_downloads.indexOf(item);

    if (-1 == row)

        return;

    if (!m_iconProvider)

        m_iconProvider = new QFileIconProvider();

    QIcon icon = m_iconProvider->icon(item->m_output.fileName());

    if (icon.isNull())

        icon = style()->standardIcon(QStyle::SP_FileIcon);

    item->fileIcon->setPixmap(icon.pixmap(48, 48));

    downloadsView->setRowHeight(row, item->minimumSizeHint().height());

    bool remove = false;

    QWebSettings *globalSettings = QWebSettings::globalSettings();

    if (!item->downloading()

        && globalSettings->testAttribute(QWebSettings::PrivateBrowsingEnabled))

        remove = true;

    if (item->downloadedSuccessfully()

        && removePolicy() == DownloadManager::SuccessFullDownload) {

        remove = true;

    }

    if (remove)

        m_model->removeRow(row);

    cleanupButton->setEnabled(m_downloads.count() - activeDownloads() > 0);

}

DownloadManager::RemovePolicy DownloadManager::removePolicy() const

{

    return m_removePolicy;

}

void DownloadManager::setRemovePolicy(RemovePolicy policy)

{

    if (policy == m_removePolicy)

        return;

    m_removePolicy = policy;

    m_autoSaver->changeOccurred();

}

void DownloadManager::save() const

{

    QSettings settings;

    settings.beginGroup(QLatin1String("downloadmanager"));

    QMetaEnum removePolicyEnum = staticMetaObject.enumerator(staticMetaObject.indexOfEnumerator("RemovePolicy"));

    settings.setValue(QLatin1String("removeDownloadsPolicy"), QLatin1String(removePolicyEnum.valueToKey(m_removePolicy)));

    settings.setValue(QLatin1String("size"), size());

    if (m_removePolicy == Exit)

        return;

    for (int i = 0; i < m_downloads.count(); ++i) {

        QString key = QString(QLatin1String("download_%1_")).arg(i);

        settings.setValue(key + QLatin1String("url"), m_downloads[i]->m_url);

        settings.setValue(key + QLatin1String("location"), QFileInfo(m_downloads[i]->m_output).filePath());

        settings.setValue(key + QLatin1String("done"), m_downloads[i]->downloadedSuccessfully());

    }

    int i = m_downloads.count();

    QString key = QString(QLatin1String("download_%1_")).arg(i);

    while (settings.contains(key + QLatin1String("url"))) {

        settings.remove(key + QLatin1String("url"));

        settings.remove(key + QLatin1String("location"));

        settings.remove(key + QLatin1String("done"));

        key = QString(QLatin1String("download_%1_")).arg(++i);

    }

}

void DownloadManager::load()

{

    QSettings settings;

    settings.beginGroup(QLatin1String("downloadmanager"));

    QSize size = settings.value(QLatin1String("size")).toSize();

    if (size.isValid())

        resize(size);

    QByteArray value = settings.value(QLatin1String("removeDownloadsPolicy"), QLatin1String("Never")).toByteArray();

    QMetaEnum removePolicyEnum = staticMetaObject.enumerator(staticMetaObject.indexOfEnumerator("RemovePolicy"));

    m_removePolicy = removePolicyEnum.keyToValue(value) == -1 ?

                        Never :

                        static_cast<RemovePolicy>(removePolicyEnum.keyToValue(value));

    int i = 0;

    QString key = QString(QLatin1String("download_%1_")).arg(i);

    while (settings.contains(key + QLatin1String("url"))) {

        QUrl url = settings.value(key + QLatin1String("url")).toUrl();

        QString fileName = settings.value(key + QLatin1String("location")).toString();

        bool done = settings.value(key + QLatin1String("done"), true).toBool();

        if (!url.isEmpty() && !fileName.isEmpty()) {

            DownloadItem *item = new DownloadItem(0, this);

            item->m_output.setFileName(fileName);

            item->fileNameLabel->setText(QFileInfo(item->m_output.fileName()).fileName());

            item->m_url = url;

            item->stopButton->setVisible(false);

            item->stopButton->setEnabled(false);

            item->tryAgainButton->setVisible(!done);

            item->tryAgainButton->setEnabled(!done);

            item->progressBar->setVisible(!done);

            addItem(item);

        }

        key = QString(QLatin1String("download_%1_")).arg(++i);

    }

    cleanupButton->setEnabled(m_downloads.count() - activeDownloads() > 0);

}

void DownloadManager::cleanup()

{

    if (m_downloads.isEmpty())

        return;

    m_model->removeRows(0, m_downloads.count());

    updateItemCount();

    if (m_downloads.isEmpty() && m_iconProvider) {