/*
    Copyright (c) 2009 Kevin Ottens <ervin@kde.org>

    This library is free software; you can redistribute it and/or modify it
    under the terms of the GNU Library General Public License as published by
    the Free Software Foundation; either version 2 of the License, or (at your
    option) any later version.

    This library is distributed in the hope that it will be useful, but WITHOUT
    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
    License for more details.

    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to the
    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
    02110-1301, USA.
*/

#include "statisticsproxymodel.h"

#include "entitytreemodel.h"
#include "collectionutils_p.h"

#include <akonadi/collectionquotaattribute.h>
#include <akonadi/collectionstatistics.h>
#include <akonadi/entitydisplayattribute.h>

#include <kdebug.h>
#include <kiconloader.h>
#include <klocalizedstring.h>
#include <kio/global.h>

#include <QApplication>
#include <QPalette>
#include <KIcon>
using namespace Akonadi;

/**
 * @internal
 */
class StatisticsProxyModel::Private
{
public:
    Private(StatisticsProxyModel *parent)
        : mParent(parent)
        , mToolTipEnabled(false)
        , mExtraColumnsEnabled(true)
    {
    }

    int sourceColumnCount(const QModelIndex &parent)
    {
        return mParent->sourceModel()->columnCount(mParent->mapToSource(parent));
    }

    void getCountRecursive(const QModelIndex &index, qint64 &totalSize) const
    {
        Collection collection = qvariant_cast<Collection>(index.data(EntityTreeModel::CollectionRole));
        // Do not assert on invalid collections, since a collection may be deleted
        // in the meantime and deleted collections are invalid.
        if (collection.isValid()) {
            CollectionStatistics statistics = collection.statistics();
            totalSize += qMax(0LL, statistics.size());
            if (index.model()->hasChildren(index)) {
                const int rowCount = index.model()->rowCount(index);
                for (int row = 0; row < rowCount; row++) {
                    static const int column = 0;
                    getCountRecursive(index.model()->index(row, column, index),  totalSize);
                }
            }
        }
    }

    QString toolTipForCollection(const QModelIndex &index, const Collection &collection)
    {
        QString bckColor = QApplication::palette().color(QPalette::ToolTipBase).name();
        QString txtColor = QApplication::palette().color(QPalette::ToolTipText).name();

        QString tip = QString::fromLatin1(
                          "<table width=\"100%\" border=\"0\" cellpadding=\"2\" cellspacing=\"0\">\n"
                      );
        const QString textDirection = (QApplication::layoutDirection() == Qt::LeftToRight) ? QLatin1String("left") : QLatin1String("right");
        tip += QString::fromLatin1(
                   "  <tr>\n"
                   "    <td bgcolor=\"%1\" colspan=\"2\" align=\"%4\" valign=\"middle\">\n"
                   "      <div style=\"color: %2; font-weight: bold;\">\n"
                   "      %3\n"
                   "      </div>\n"
                   "    </td>\n"
                   "  </tr>\n"
               ).arg(txtColor).arg(bckColor).arg(index.data(Qt::DisplayRole).toString()).arg(textDirection);

        tip += QString::fromLatin1(
                   "  <tr>\n"
                   "    <td align=\"%1\" valign=\"top\">\n"
               ).arg(textDirection);

        QString tipInfo;
        tipInfo += QString::fromLatin1(
                       "      <strong>%1</strong>: %2<br>\n"
                       "      <strong>%3</strong>: %4<br><br>\n"
                   ).arg(i18n("Total Messages")).arg(collection.statistics().count())
                   .arg(i18n("Unread Messages")).arg(collection.statistics().unreadCount());

        if (collection.hasAttribute<CollectionQuotaAttribute>()) {
            CollectionQuotaAttribute *quota = collection.attribute<CollectionQuotaAttribute>();
            if (quota->currentValue() > -1 && quota->maximumValue() > 0) {
                qreal percentage = (100.0 * quota->currentValue()) / quota->maximumValue();

                if (qAbs(percentage) >= 0.01) {
                    QString percentStr = QString::number(percentage, 'f', 2);
                    tipInfo += QString::fromLatin1(
                                   "      <strong>%1</strong>: %2%<br>\n"
                               ).arg(i18n("Quota")).arg(percentStr);
                }
            }
        }

        qint64 currentFolderSize(collection.statistics().size());
        tipInfo += QString::fromLatin1(
                       "      <strong>%1</strong>: %2<br>\n"
                   ).arg(i18n("Storage Size")).arg(KIO::convertSize((KIO::filesize_t)(currentFolderSize)));

        qint64 totalSize = 0;
        getCountRecursive(index, totalSize);
        totalSize -= currentFolderSize;
        if (totalSize > 0) {
            tipInfo += QString::fromLatin1(
                           "<strong>%1</strong>: %2<br>"
                       ).arg(i18n("Subfolder Storage Size")).arg(KIO::convertSize((KIO::filesize_t)(totalSize)));
        }

        QString iconName = CollectionUtils::defaultIconName(collection);
        if (collection.hasAttribute<EntityDisplayAttribute>() &&
            !collection.attribute<EntityDisplayAttribute>()->iconName().isEmpty()) {
            if (!collection.attribute<EntityDisplayAttribute>()->activeIconName().isEmpty() && collection.statistics().unreadCount() > 0) {
                iconName = collection.attribute<EntityDisplayAttribute>()->activeIconName();
            } else {
                iconName = collection.attribute<EntityDisplayAttribute>()->iconName();
            }
        }

        int iconSizes[] = { 32, 22 };
        int icon_size_found = 32;

        QString iconPath;

        for (int i = 0; i < 2; i++) {
            iconPath = KIconLoader::global()->iconPath(iconName, -iconSizes[i], true);
            if (!iconPath.isEmpty()) {
                icon_size_found = iconSizes[i];
                break;
            }
        }

        if (iconPath.isEmpty()) {
            iconPath = KIconLoader::global()->iconPath(QLatin1String("folder"), -32, false);
        }

        QString tipIcon = QString::fromLatin1(
                              "      <table border=\"0\"><tr><td width=\"32\" height=\"32\" align=\"center\" valign=\"middle\">\n"
                              "      <img src=\"%1\" width=\"%2\" height=\"32\">\n"
                              "      </td></tr></table>\n"
                              "    </td>\n"
                          ).arg(iconPath).arg(icon_size_found) ;

        if (QApplication::layoutDirection() == Qt::LeftToRight) {
            tip += tipInfo + QString::fromLatin1("</td><td align=\"%3\" valign=\"top\">").arg(textDirection) + tipIcon;
        } else {
            tip += tipIcon + QString::fromLatin1("</td><td align=\"%3\" valign=\"top\">").arg(textDirection) + tipInfo;
        }

        tip += QString::fromLatin1(
                   "  </tr>" \
                   "</table>"
               );

        return tip;
    }

    void proxyDataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight);

    void sourceLayoutAboutToBeChanged();
    void sourceLayoutChanged();

    QVector<QModelIndex> m_nonPersistent;
    QVector<QModelIndex> m_nonPersistentFirstColumn;
    QVector<QPersistentModelIndex> m_persistent;
    QVector<QPersistentModelIndex> m_persistentFirstColumn;

    StatisticsProxyModel *mParent;

    bool mToolTipEnabled;
    bool mExtraColumnsEnabled;
};

void StatisticsProxyModel::Private::proxyDataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight)
{
    if (mExtraColumnsEnabled) {
        // Ugly hack.
        // The proper solution is a KExtraColumnsProxyModel, but this will do for now.
        QModelIndex parent = topLeft.parent();
        int parentColumnCount = mParent->columnCount(parent);
        QModelIndex extraTopLeft = mParent->index(topLeft.row(), parentColumnCount - 1 - 3 , parent);
        QModelIndex extraBottomRight = mParent->index(bottomRight.row(), parentColumnCount - 1, parent);
        mParent->disconnect(mParent, SIGNAL(dataChanged(QModelIndex,QModelIndex)),
                            mParent, SLOT(proxyDataChanged(QModelIndex,QModelIndex)));
        emit mParent->dataChanged(extraTopLeft, extraBottomRight);

        // We get this signal when the statistics of a row changes.
        // However, we need to emit data changed for the statistics of all ancestor rows too
        // so that recursive totals can be updated.
        while (parent.isValid()) {
            emit mParent->dataChanged(parent.sibling(parent.row(), parentColumnCount - 1 - 3),
                                      parent.sibling(parent.row(), parentColumnCount - 1));
            parent = parent.parent();
            parentColumnCount = mParent->columnCount(parent);
        }
        mParent->connect(mParent, SIGNAL(dataChanged(QModelIndex,QModelIndex)),
                         SLOT(proxyDataChanged(QModelIndex,QModelIndex)));
    }
}

void StatisticsProxyModel::Private::sourceLayoutAboutToBeChanged()
{
    QModelIndexList persistent = mParent->persistentIndexList();
    const int columnCount = mParent->sourceModel()->columnCount();
    foreach (const QModelIndex &idx, persistent) {
        if (idx.column() >= columnCount) {
            m_nonPersistent.push_back(idx);
            m_persistent.push_back(idx);
            const QModelIndex firstColumn = idx.sibling(0, idx.column());
            m_nonPersistentFirstColumn.push_back(firstColumn);
            m_persistentFirstColumn.push_back(firstColumn);
        }
    }
}

void StatisticsProxyModel::Private::sourceLayoutChanged()
{
    QModelIndexList oldList;
    QModelIndexList newList;

    const int columnCount = mParent->sourceModel()->columnCount();

    for (int i = 0; i < m_persistent.size(); ++i) {
        const QModelIndex persistentIdx = m_persistent.at(i);
        const QModelIndex nonPersistentIdx = m_nonPersistent.at(i);
        if (m_persistentFirstColumn.at(i) != m_nonPersistentFirstColumn.at(i) && persistentIdx.column() >= columnCount) {
            oldList.append(nonPersistentIdx);
            newList.append(persistentIdx);
        }
    }
    mParent->changePersistentIndexList(oldList, newList);
}

void StatisticsProxyModel::setSourceModel(QAbstractItemModel *sourceModel)
{
    // Order is important here. sourceLayoutChanged must be called *before* any downstreams react
    // to the layoutChanged so that it can have the QPersistentModelIndexes uptodate in time.
    disconnect(this, SIGNAL(layoutChanged()), this, SLOT(sourceLayoutChanged()));
    connect(this, SIGNAL(layoutChanged()), SLOT(sourceLayoutChanged()));
    QSortFilterProxyModel::setSourceModel(sourceModel);
    // This one should come *after* any downstream handlers of layoutAboutToBeChanged.
    // The connectNotify stuff below ensures that it remains the last one.
    disconnect(this, SIGNAL(layoutAboutToBeChanged()), this, SLOT(sourceLayoutAboutToBeChanged()));
    connect(this, SIGNAL(layoutAboutToBeChanged()), SLOT(sourceLayoutAboutToBeChanged()));
}

void StatisticsProxyModel::connectNotify(const char *signal)
{
    static bool ignore = false;
    if (ignore || QLatin1String(signal) == SIGNAL(layoutAboutToBeChanged())) {
        return QSortFilterProxyModel::connectNotify(signal);
    }
    ignore = true;
    disconnect(this, SIGNAL(layoutAboutToBeChanged()), this, SLOT(sourceLayoutAboutToBeChanged()));
    connect(this, SIGNAL(layoutAboutToBeChanged()), SLOT(sourceLayoutAboutToBeChanged()));
    ignore = false;
    QSortFilterProxyModel::connectNotify(signal);
}

StatisticsProxyModel::StatisticsProxyModel(QObject *parent)
    : QSortFilterProxyModel(parent)
    , d(new Private(this))
{
    connect(this, SIGNAL(dataChanged(QModelIndex,QModelIndex)),
            SLOT(proxyDataChanged(QModelIndex,QModelIndex)));
}

StatisticsProxyModel::~StatisticsProxyModel()
{
    delete d;
}

void StatisticsProxyModel::setToolTipEnabled(bool enable)
{
    d->mToolTipEnabled = enable;
}

bool StatisticsProxyModel::isToolTipEnabled() const
{
    return d->mToolTipEnabled;
}

void StatisticsProxyModel::setExtraColumnsEnabled(bool enable)
{
    d->mExtraColumnsEnabled = enable;
}

bool StatisticsProxyModel::isExtraColumnsEnabled() const
{
    return d->mExtraColumnsEnabled;
}

QModelIndex Akonadi::StatisticsProxyModel::index(int row, int column, const QModelIndex &parent) const
{
    if (!hasIndex(row, column, parent)) {
        return QModelIndex();
    }

    int sourceColumn = column;

    if (column >= d->sourceColumnCount(parent)) {
        sourceColumn = 0;
    }

    QModelIndex i = QSortFilterProxyModel::index(row, sourceColumn, parent);
    return createIndex(i.row(), column, i.internalPointer());
}

QVariant StatisticsProxyModel::data(const QModelIndex &index, int role) const
{
    if (!sourceModel()) {
        return QVariant();
    }
    if (role == Qt::DisplayRole && index.column() >= d->sourceColumnCount(index.parent())) {
        const QModelIndex sourceIndex = mapToSource(index.sibling(index.row(), 0));
        Collection collection = sourceModel()->data(sourceIndex, EntityTreeModel::CollectionRole).value<Collection>();

        if (collection.isValid() && collection.statistics().count() >= 0) {
            if (index.column() == d->sourceColumnCount(QModelIndex()) + 2) {
                return KIO::convertSize((KIO::filesize_t)(collection.statistics().size()));
            } else if (index.column() == d->sourceColumnCount(QModelIndex()) + 1) {
                return collection.statistics().count();
            } else if (index.column() == d->sourceColumnCount(QModelIndex())) {
                if (collection.statistics().unreadCount() > 0) {
                    return collection.statistics().unreadCount();
                } else {
                    return QString();
                }
            } else {
                kWarning() << "We shouldn't get there for a column which is not total, unread or size.";
                return QVariant();
            }
        }

    } else if (role == Qt::TextAlignmentRole && index.column() >= d->sourceColumnCount(index.parent())) {
        return Qt::AlignRight;

    } else if (role == Qt::ToolTipRole && d->mToolTipEnabled) {
        const QModelIndex sourceIndex = mapToSource(index.sibling(index.row(), 0));
        Collection collection = sourceModel()->data(sourceIndex, EntityTreeModel::CollectionRole).value<Collection>();

        if (collection.isValid() && collection.statistics().count() > 0) {
            return d->toolTipForCollection(index, collection);
        }

    } else if (role == Qt::DecorationRole && index.column() == 0) {
        const QModelIndex sourceIndex = mapToSource(index.sibling(index.row(), 0));
        Collection collection = sourceModel()->data(sourceIndex, EntityTreeModel::CollectionRole).value<Collection>();

        if (collection.isValid()) {
            return KIcon(CollectionUtils::displayIconName(collection));
        } else {
            return QVariant();
        }
    }

    return QAbstractProxyModel::data(index, role);
}

QVariant StatisticsProxyModel::headerData(int section, Qt::Orientation orientation, int role) const
{
    if (orientation == Qt::Horizontal && role == Qt::DisplayRole) {
        if (section == d->sourceColumnCount(QModelIndex()) + 2) {
            return i18nc("collection size", "Size");
        } else if (section == d->sourceColumnCount(QModelIndex()) + 1) {
            return i18nc("number of entities in the collection", "Total");
        } else if (section == d->sourceColumnCount(QModelIndex())) {
            return i18nc("number of unread entities in the collection", "Unread");
        }
    }

    return QSortFilterProxyModel::headerData(section, orientation, role);
}

Qt::ItemFlags StatisticsProxyModel::flags(const QModelIndex &index) const
{
    if (index.column() >= d->sourceColumnCount(index.parent())) {
        return QSortFilterProxyModel::flags(index.sibling(index.row(), 0))
               & (Qt::ItemIsSelectable | Qt::ItemIsDragEnabled  // Allowed flags
                  | Qt::ItemIsDropEnabled | Qt::ItemIsEnabled);
    }

    return QSortFilterProxyModel::flags(index);
}

int StatisticsProxyModel::columnCount(const QModelIndex &parent) const
{
    if (sourceModel() == 0) {
        return 0;
    } else {
        return d->sourceColumnCount(parent)
               + (d->mExtraColumnsEnabled ? 3 : 0);
    }
}

QModelIndexList StatisticsProxyModel::match(const QModelIndex &start, int role, const QVariant &value,
                                            int hits, Qt::MatchFlags flags) const
{
    if (role < Qt::UserRole) {
        return QSortFilterProxyModel::match(start, role, value, hits, flags);
    }

    QModelIndexList list;
    QModelIndex proxyIndex;
    foreach (const QModelIndex &idx, sourceModel()->match(mapToSource(start), role, value, hits, flags)) {
        proxyIndex = mapFromSource(idx);
        if (proxyIndex.isValid()) {
            list << proxyIndex;
        }
    }

    return list;
}

#include "moc_statisticsproxymodel.cpp"