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#include "progresscoordinator.h"

#include <QtCore/QCoreApplication>
#include <QtCore/QDebug>

using namespace QInstaller;

QT_BEGIN_NAMESPACE
uint qHash(QPointer<QObject> key)
{
    return qHash(key.data());
}
QT_END_NAMESPACE

ProgressCoordinator::ProgressCoordinator(QObject *parent)
    : QObject(parent)
    , m_currentCompletePercentage(0)
    , m_currentBasePercentage(0)
    , m_manualAddedPercentage(0)
    , m_reservedPercentage(0)
    , m_undoMode(false)
    , m_reachedPercentageBeforeUndo(0)
{
    // it has to be in the main thread to be able refresh the ui with processEvents
    Q_ASSERT(thread() == qApp->thread());
}

ProgressCoordinator::~ProgressCoordinator()
{
}

ProgressCoordinator *ProgressCoordinator::instance()
{
    static ProgressCoordinator *instance = 0;
    if (instance == 0)
        instance = new ProgressCoordinator(qApp);
    return instance;
}

void ProgressCoordinator::reset()
{
    disconnectAllSenders();
    m_installationLabelText.clear();
    m_currentCompletePercentage = 0;
    m_currentBasePercentage = 0;
    m_manualAddedPercentage = 0;
    m_reservedPercentage = 0;
    m_undoMode = false;
    m_reachedPercentageBeforeUndo = 0;
    emit detailTextResetNeeded();
}

void ProgressCoordinator::registerPartProgress(QObject *sender, const char *signal, double partProgressSize)
{
    Q_ASSERT(sender);
    Q_ASSERT(QString::fromLatin1(signal).contains(QLatin1String("(double)")));
    Q_ASSERT(partProgressSize <= 1);

    m_senderPartProgressSizeHash.insert(sender, partProgressSize);
    bool isConnected = connect(sender, signal, this, SLOT(partProgressChanged(double)));
    Q_UNUSED(isConnected);
    Q_ASSERT(isConnected);
}


/*!
    This slot gets the progress changed signals from different tasks. The values 0 and 1 are handled as
    special values.

    0 - is just ignored, so you can use a timer which gives the progress, e.g. like a downloader does.
    1 - means the task is finished, even if there comes another 1 from that task, so it will be ignored.
*/
void ProgressCoordinator::partProgressChanged(double fraction)
{
    if (fraction < 0 || fraction > 1) {
        qWarning() << "The fraction is outside from possible value:" << QString::number(fraction);
        return;
    }

    // no fraction no change
    if (fraction == 0)
        return;

    // ignore senders sending 100% multiple times
    if (fraction == 1 && m_senderPendingCalculatedPercentageHash.contains(sender())
        && m_senderPendingCalculatedPercentageHash.value(sender()) == 0) {
        return;
    }

    double partProgressSize = m_senderPartProgressSizeHash.value(sender(), 0);
    if (partProgressSize == 0) {
        qWarning() << "It seems that this sender was not registered in the right way:" << sender();
        return;
    }

    if (m_undoMode) {
        //qDebug() << "fraction:" << fraction;
        double maxSize = m_reachedPercentageBeforeUndo * partProgressSize;
        double pendingCalculatedPartPercentage = maxSize * fraction;

         // allPendingCalculatedPartPercentages has negative values
        double newCurrentCompletePercentage = m_currentBasePercentage - pendingCalculatedPartPercentage
            + allPendingCalculatedPartPercentages(sender());

        //we can't check this here, because some round issues can make it little bit under 0 or over 100
        //Q_ASSERT(newCurrentCompletePercentage >= 0);
        //Q_ASSERT(newCurrentCompletePercentage <= 100);
        if (newCurrentCompletePercentage < 0) {
            qDebug() << newCurrentCompletePercentage << "is smaller then 0 - this should happen max once";
            newCurrentCompletePercentage = 0;
        }
        if (newCurrentCompletePercentage > 100) {
            qDebug() << newCurrentCompletePercentage << "is bigger then 100 - this should happen max once";
            newCurrentCompletePercentage = 100;
        }

        // In undo mode, the progress has to go backward, new has to be smaller than current
        if (qRound(m_currentCompletePercentage) < qRound(newCurrentCompletePercentage))
            qDebug("Something is wrong with the calculation of the progress.");

        m_currentCompletePercentage = newCurrentCompletePercentage;
        if (fraction == 1) {
            m_currentBasePercentage = m_currentBasePercentage - pendingCalculatedPartPercentage;
            m_senderPendingCalculatedPercentageHash.insert(sender(), 0);
        } else {
            m_senderPendingCalculatedPercentageHash.insert(sender(), pendingCalculatedPartPercentage);
        }

    } else { //if (m_undoMode)
        int availablePercentagePoints = 100 - m_manualAddedPercentage - m_reservedPercentage;
        double pendingCalculatedPartPercentage = availablePercentagePoints * partProgressSize * fraction;
        //double checkValue = allPendingCalculatedPartPercentages(sender());

        double newCurrentCompletePercentage = m_manualAddedPercentage + m_currentBasePercentage
            + pendingCalculatedPartPercentage + allPendingCalculatedPartPercentages(sender());

        //we can't check this here, because some round issues can make it little bit under 0 or over 100
        //Q_ASSERT(newCurrentCompletePercentage >= 0);
        //Q_ASSERT(newCurrentCompletePercentage <= 100);
        if (newCurrentCompletePercentage < 0) {
            qDebug() << newCurrentCompletePercentage << "is smaller then 0 - this should happen max once";
            newCurrentCompletePercentage = 0;
        }

        if (newCurrentCompletePercentage > 100) {
            qDebug() << newCurrentCompletePercentage << "is bigger then 100 - this should happen max once";
            newCurrentCompletePercentage = 100;
        }

        // In normal mode, the progress has to go forward, new has to be larger than current
        if (qRound(m_currentCompletePercentage) > qRound(newCurrentCompletePercentage))
            qDebug("Something is wrong with the calculation of the progress.");

        m_currentCompletePercentage = newCurrentCompletePercentage;

        if (fraction == 1) {
            m_currentBasePercentage = m_currentBasePercentage + pendingCalculatedPartPercentage;
            m_senderPendingCalculatedPercentageHash.insert(sender(), 0);
        } else {
            m_senderPendingCalculatedPercentageHash.insert(sender(), pendingCalculatedPartPercentage);
        }
    } //if (m_undoMode)
}


/*!
    Contains the installation progress percentage.
*/
int ProgressCoordinator::progressInPercentage() const
{
    int currentValue = qRound(m_currentCompletePercentage);
    Q_ASSERT( currentValue <= 100);
    Q_ASSERT( currentValue >= 0);
    return currentValue;
}

void ProgressCoordinator::disconnectAllSenders()
{
    foreach (QPointer<QObject> sender, m_senderPartProgressSizeHash.keys()) {
        if (!sender.isNull()) {
            bool isDisconnected = sender->disconnect(this);
            Q_UNUSED(isDisconnected);
            Q_ASSERT(isDisconnected);
        }
    }
    m_senderPartProgressSizeHash.clear();
    m_senderPendingCalculatedPercentageHash.clear();
}

void ProgressCoordinator::setUndoMode()
{
    Q_ASSERT(!m_undoMode);
    m_undoMode = true;

    disconnectAllSenders();
    m_reachedPercentageBeforeUndo = progressInPercentage();
    m_currentBasePercentage = m_reachedPercentageBeforeUndo;
}

void ProgressCoordinator::addManualPercentagePoints(int value)
{
    m_manualAddedPercentage = m_manualAddedPercentage + value;
    if (m_undoMode) {
        //we don't do other things in the undomode, maybe later if the last percentage point comes to early
        return;
    }

    m_currentCompletePercentage = m_currentCompletePercentage + value;
    if (m_currentCompletePercentage > 100.0)
        m_currentCompletePercentage = 100.0;

    qApp->processEvents(); //makes the result available in the ui
}

void ProgressCoordinator::addReservePercentagePoints(int value)
{
    m_reservedPercentage = m_reservedPercentage + value;
}

void ProgressCoordinator::setLabelText(const QString &text)
{
    if (m_installationLabelText == text)
        return;
    m_installationLabelText = text;
}

/*!
    Contains the installation progress label text.
*/
QString ProgressCoordinator::labelText() const
{
    return m_installationLabelText;
}

void ProgressCoordinator::emitDetailTextChanged(const QString &text)
{
    emit detailTextChanged(text);
}

void ProgressCoordinator::emitLabelAndDetailTextChanged(const QString &text)
{
    emit detailTextChanged(text);
    m_installationLabelText = QString(text).remove(QLatin1String("\n"));
    qApp->processEvents(); //makes the result available in the ui
}

double ProgressCoordinator::allPendingCalculatedPartPercentages(QObject *excludeKeyObject)
{
    double result = 0;
    QHash<QPointer<QObject>, double>::iterator it = m_senderPendingCalculatedPercentageHash.begin();
    while (it != m_senderPendingCalculatedPercentageHash.end()) {
        if (it.key() != excludeKeyObject)
            result += it.value();
        it++;
    }
    return result;
}

void ProgressCoordinator::emitDownloadStatus(const QString &status)
{
    emit downloadStatusChanged(status);
}