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#include "resourcemodel.h"

#include <qstack.h>
#include <qfile.h>
#include <qurl.h>
#include <qmimedata.h>
#include <qpair.h>
#include <qvector.h>
#include <qobject.h>
#include <qdatetime.h>
#include <qlocale.h>
#include <qcoreapplication.h>
#include <qdebug.h>

/*!
    \enum ResourceModel::Roles
    \value FilePathRole
    \value FileNameRole
*/

using namespace GammaRay;

class GammaRay::ResourceModelPrivate
{
    Q_DECLARE_PUBLIC(ResourceModel)
    ResourceModel * const q_ptr;

public:
    struct QDirNode
    {
        QDirNode() : parent(nullptr), populated(false), stat(false) {}
        ~QDirNode() { children.clear(); }
        QDirNode *parent;
        QFileInfo info;
        mutable QVector<QDirNode> children;
        mutable bool populated; // have we read the children
        mutable bool stat;
    };

    ResourceModelPrivate(ResourceModel *qq)
        : q_ptr(qq),
          resolveSymlinks(true),
          readOnly(true),
          lazyChildCount(false),
          allowAppendChild(true),
          shouldStat(true) // ### This is set to false by QFileDialog
    { }

    bool indexValid(const QModelIndex &index) const { return index.isValid(); }

    void init();
    QDirNode *node(int row, QDirNode *parent) const;
    QVector<QDirNode> children(QDirNode *parent, bool stat) const;

    void _q_refresh();

    void savePersistentIndexes();
    void restorePersistentIndexes();

    QFileInfoList entryInfoList(const QString &path) const;
    QStringList entryList(const QString &path) const;

    QString name(const QModelIndex &index) const;
    QString size(const QModelIndex &index) const;
    QString type(const QModelIndex &index) const;
    QString time(const QModelIndex &index) const;

    void appendChild(ResourceModelPrivate::QDirNode *parent, const QString &path) const;
    static QFileInfo resolvedInfo(QFileInfo info);

    inline QDirNode *node(const QModelIndex &index) const;
    inline void populate(QDirNode *parent) const;
    inline void clear(QDirNode *parent) const;

    void invalidate();

    mutable QDirNode root;
    bool resolveSymlinks;
    bool readOnly;
    bool lazyChildCount;
    bool allowAppendChild;

    QDir::Filters filters;
    QDir::SortFlags sort;
    QStringList nameFilters;

    struct SavedPersistent {
        QString path;
        int column;
        QPersistentModelIndexData *data;
        QPersistentModelIndex index;
    };
    QList<SavedPersistent> savedPersistent;
    QPersistentModelIndex toBeRefreshed;

    bool shouldStat; // use the "carefull not to stat directories" mode
};

void qt_setDirModelShouldNotStat(ResourceModelPrivate *modelPrivate)
{
    modelPrivate->shouldStat = false;
}

ResourceModelPrivate::QDirNode *ResourceModelPrivate::node(const QModelIndex &index) const
{
    ResourceModelPrivate::QDirNode *n =
        static_cast<ResourceModelPrivate::QDirNode*>(index.internalPointer());
    Q_ASSERT(n);
    return n;
}

void ResourceModelPrivate::populate(QDirNode *parent) const
{
    Q_ASSERT(parent);
    parent->children = children(parent, parent->stat);
    parent->populated = true;
}

void ResourceModelPrivate::clear(QDirNode *parent) const
{
     Q_ASSERT(parent);
     parent->children.clear();
     parent->populated = false;
}

void ResourceModelPrivate::invalidate()
{
    QStack<const QDirNode*> nodes;
    nodes.push(&root);
    while (!nodes.empty()) {
        const QDirNode *current = nodes.pop();
        current->stat = false;
        const QVector<QDirNode> children = current->children;
        for (int i = 0; i < children.count(); ++i)
            nodes.push(&children.at(i));
    }
}

/*!
    \class ResourceModel
    \obsolete
    \brief The ResourceModel class provides a data model for the local filesystem.

    \ingroup model-view

    The usage of ResourceModel is not recommended anymore. The
    QFileSystemModel class is a more performant alternative.

    This class provides access to the local filesystem, providing functions
    for renaming and removing files and directories, and for creating new
    directories. In the simplest case, it can be used with a suitable display
    widget as part of a browser or filer.

    ResourceModel keeps a cache with file information. The cache needs to be
    updated with refresh().

    ResourceModel can be accessed using the standard interface provided by
    QAbstractItemModel, but it also provides some convenience functions
    that are specific to a directory model. The fileInfo() and isDir()
    functions provide information about the underlying files and directories
    related to items in the model.

    Directories can be created and removed using mkdir(), rmdir(), and the
    model will be automatically updated to take the changes into account.

    \note ResourceModel requires an instance of a GUI application.

    \sa nameFilters(), setFilter(), filter(), QListView, QTreeView, QFileSystemModel,
    {Dir View Example}, {Model Classes}
*/

/*!
    Constructs a new directory model with the given \a parent.
    Only those files matching the \a nameFilters and the
    \a filters are included in the model. The sort order is given by the
    \a sort flags.
*/

ResourceModel::ResourceModel(const QStringList &nameFilters,
                     QDir::Filters filters,
                     QDir::SortFlags sort,
                     QObject *parent)
    : QAbstractItemModel(parent), d_ptr(new ResourceModelPrivate(this))
{
    Q_D(ResourceModel);
    // we always start with QDir::drives()
    d->nameFilters = nameFilters.isEmpty() ? QStringList(QLatin1String("*")) : nameFilters;
    d->filters = filters;
    d->sort = sort;
    d->root.parent = nullptr;
    d->root.info = QFileInfo();
    d->clear(&d->root);
}

/*!
  Constructs a directory model with the given \a parent.
*/

ResourceModel::ResourceModel(QObject *parent)
    : QAbstractItemModel(parent), d_ptr(new ResourceModelPrivate(this))
{
    Q_D(ResourceModel);
    d->init();
}

/*!
  Destroys this directory model.
*/

ResourceModel::~ResourceModel()
{
    delete d_ptr;
}

/*!
  Returns the model item index for the item in the \a parent with the
  given \a row and \a column.

*/

QModelIndex ResourceModel::index(int row, int column, const QModelIndex &parent) const
{
    Q_D(const ResourceModel);
    // note that rowCount does lazy population
    if (column < 0 || column >= columnCount(parent) || row < 0 || parent.column() > 0)
        return QModelIndex();
    // make sure the list of children is up to date
    ResourceModelPrivate::QDirNode *p = (d->indexValid(parent) ? d->node(parent) : &d->root);
    Q_ASSERT(p);
    if (!p->populated)
        d->populate(p); // populate without stat'ing
    if (row >= p->children.count())
        return QModelIndex();
    // now get the internal pointer for the index
    ResourceModelPrivate::QDirNode *n = d->node(row, d->indexValid(parent) ? p : nullptr);
    Q_ASSERT(n);

    return createIndex(row, column, n);
}

/*!
  Return the parent of the given \a child model item.
*/

QModelIndex ResourceModel::parent(const QModelIndex &child) const
{
    Q_D(const ResourceModel);

    if (!d->indexValid(child))
	return QModelIndex();
    ResourceModelPrivate::QDirNode *node = d->node(child);
    ResourceModelPrivate::QDirNode *par = (node ? node->parent : nullptr);
    if (par == nullptr) // parent is the root node
	return QModelIndex();

    // get the parent's row
    const QVector<ResourceModelPrivate::QDirNode> children =
        par->parent ? par->parent->children : d->root.children;
    Q_ASSERT(children.count() > 0);
    int row = (par - &(children.at(0)));
    Q_ASSERT(row >= 0);

    return createIndex(row, 0, par);
}

/*!
  Returns the number of rows in the \a parent model item.

*/

int ResourceModel::rowCount(const QModelIndex &parent) const
{
    Q_D(const ResourceModel);
    if (parent.column() > 0)
        return 0;

    if (!parent.isValid()) {
//       qDebug() << "Root" << d->root;
        if (!d->root.populated) // lazy population
            d->populate(&d->root);
        return d->root.children.count();
    }
    if (parent.model() != this)
        return 0;
    ResourceModelPrivate::QDirNode *p = d->node(parent);
    if (p->info.isDir() && !p->populated) // lazy population
        d->populate(p);
    return p->children.count();
}

/*!
  Returns the number of columns in the \a parent model item.

*/

int ResourceModel::columnCount(const QModelIndex &parent) const
{
    if (parent.column() > 0)
        return 0;
    return 4;
}

/*!
  Returns the data for the model item \a index with the given \a role.
*/
QVariant ResourceModel::data(const QModelIndex &index, int role) const
{
    Q_D(const ResourceModel);
    if (!d->indexValid(index))
        return QVariant();

    if (role == Qt::DisplayRole || role == Qt::EditRole) {
        switch (index.column()) {
        case 0: return d->name(index);
        case 1: return d->size(index);
        case 2: return d->type(index);
        case 3: return d->time(index);
        default:
            qWarning("data: invalid display value column %d", index.column());
            return QVariant();
        }
    }

    if (index.column() == 0) {
        if (role == FilePathRole)
            return filePath(index);
        if (role == FileNameRole)
            return fileName(index);
    }

    if (index.column() == 1 && Qt::TextAlignmentRole == role) {
        return QVariant::fromValue<int>(Qt::AlignRight | Qt::AlignVCenter);
    }
    return QVariant();
}

/*!
  Sets the data for the model item \a index with the given \a role to
  the data referenced by the \a value. Returns true if successful;
  otherwise returns false.

  \sa Qt::ItemDataRole
*/

bool ResourceModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
    Q_D(ResourceModel);
    if (!d->indexValid(index) || index.column() != 0
        || (flags(index) & Qt::ItemIsEditable) == 0 || role != Qt::EditRole)
        return false;

    ResourceModelPrivate::QDirNode *node = d->node(index);
    QDir dir = node->info.dir();
    QString name = value.toString();
    if (dir.rename(node->info.fileName(), name)) {
        node->info = QFileInfo(dir, name);
        QModelIndex sibling = index.sibling(index.row(), 3);
        emit dataChanged(index, sibling);

        d->toBeRefreshed = index.parent();
        QMetaObject::invokeMethod(this, "_q_refresh", Qt::QueuedConnection);

        return true;
    }

    return false;
}

/*!
  Returns the data stored under the given \a role for the specified \a section
  of the header with the given \a orientation.
*/

QVariant ResourceModel::headerData(int section, Qt::Orientation orientation, int role) const
{
    if (orientation == Qt::Horizontal) {
        if (role != Qt::DisplayRole)
            return QVariant();
	switch (section) {
        case 0: return tr("Name");
        case 1: return tr("Size");
        case 2: return
#ifdef Q_OS_MAC
                       tr("Kind", "Match OS X Finder");
#else
                       tr("Type", "All other platforms");
#endif
        // Windows   - Type
        // OS X      - Kind
        // Konqueror - File Type
        // Nautilus  - Type
        case 3: return tr("Date Modified");
        default: return QVariant();
        }
    }
    return QAbstractItemModel::headerData(section, orientation, role);
}

QMap<int, QVariant> ResourceModel::itemData(const QModelIndex &index) const
{
    QMap<int, QVariant> map = QAbstractItemModel::itemData(index);
    map.insert(ResourceModel::FilePathRole, data(index, ResourceModel::FilePathRole));
    map.insert(ResourceModel::FileNameRole, data(index, ResourceModel::FileNameRole));
    return map;
}

/*!
  Returns true if the \a parent model item has children; otherwise
  returns false.
*/

bool ResourceModel::hasChildren(const QModelIndex &parent) const
{
    Q_D(const ResourceModel);
    if (parent.column() > 0)
        return false;

    if (!parent.isValid()) // the invalid index is the "My Computer" item
        return true; // the drives
    ResourceModelPrivate::QDirNode *p = d->node(parent);
    Q_ASSERT(p);

    if (d->lazyChildCount) // optimization that only checks for children if the node has been populated
        return p->info.isDir();
    return p->info.isDir() && rowCount(parent) > 0;
}

/*!
  Returns the item flags for the given \a index in the model.

  \sa Qt::ItemFlags
*/
Qt::ItemFlags ResourceModel::flags(const QModelIndex &index) const
{
    Q_D(const ResourceModel);
    Qt::ItemFlags flags = QAbstractItemModel::flags(index);
    if (!d->indexValid(index))
        return flags;
    flags |= Qt::ItemIsDragEnabled;
    if (d->readOnly)
        return flags;
    ResourceModelPrivate::QDirNode *node = d->node(index);
    if ((index.column() == 0) && node->info.isWritable()) {
        flags |= Qt::ItemIsEditable;
        if (fileInfo(index).isDir()) // is directory and is editable
            flags |= Qt::ItemIsDropEnabled;
    }
    return flags;
}

/*!
  Sort the model items in the \a column using the \a order given.
  The order is a value defined in \l Qt::SortOrder.
*/

void ResourceModel::sort(int column, Qt::SortOrder order)
{
    QDir::SortFlags sort = QDir::DirsFirst | QDir::IgnoreCase;
    if (order == Qt::DescendingOrder)
        sort |= QDir::Reversed;

    switch (column) {
    case 0:
        sort |= QDir::Name;
        break;
    case 1:
        sort |= QDir::Size;
        break;
    case 2:
        sort |= QDir::Type;
        break;
    case 3:
        sort |= QDir::Time;
        break;
    default:
        break;
    }

    setSorting(sort);
}

/*!
    Returns a list of MIME types that can be used to describe a list of items
    in the model.
*/

QStringList ResourceModel::mimeTypes() const
{
    return QStringList(QLatin1String("text/uri-list"));
}

/*!
    Returns an object that contains a serialized description of the specified
    \a indexes. The format used to describe the items corresponding to the
    indexes is obtained from the mimeTypes() function.

    If the list of indexes is empty, 0 is returned rather than a serialized
    empty list.
*/

QMimeData *ResourceModel::mimeData(const QModelIndexList &indexes) const
{
    QList<QUrl> urls;
    QList<QModelIndex>::const_iterator it = indexes.begin();
    for (; it != indexes.end(); ++it)
        if ((*it).column() == 0)
            urls << QUrl::fromLocalFile(filePath(*it));
    auto *data = new QMimeData();
    data->setUrls(urls);
    return data;
}

/*!
    Handles the \a data supplied by a drag and drop operation that ended with
    the given \a action over the row in the model specified by the \a row and
    \a column and by the \a parent index.

    \sa supportedDropActions()
*/

bool ResourceModel::dropMimeData(const QMimeData *data, Qt::DropAction action,
                             int /* row */, int /* column */, const QModelIndex &parent)
{
    Q_D(ResourceModel);
    if (!d->indexValid(parent) || isReadOnly())
        return false;

    bool success = true;
    QString to = filePath(parent) + QDir::separator();
    QModelIndex _parent = parent;

    QList<QUrl> urls = data->urls();
    auto it = urls.constBegin();

    switch (action) {
    case Qt::CopyAction:
        for (; it != urls.constEnd(); ++it) {
            QString path = (*it).toLocalFile();
            success = QFile::copy(path, to + QFileInfo(path).fileName()) && success;
        }
        break;
    case Qt::LinkAction:
        for (; it != urls.constEnd(); ++it) {
            QString path = (*it).toLocalFile();
            success = QFile::link(path, to + QFileInfo(path).fileName()) && success;
        }
        break;
    case Qt::MoveAction:
        for (; it != urls.constEnd(); ++it) {
            QString path = (*it).toLocalFile();
            if (QFile::copy(path, to + QFileInfo(path).fileName())
               && QFile::remove(path)) {
                QModelIndex idx=index(QFileInfo(path).path());
                if (idx.isValid()) {
                    refresh(idx);
                    //the previous call to refresh may invalidate the _parent. so recreate a new QModelIndex
                    _parent = index(to);
                }
            } else {
                success = false;
            }
        }
        break;
    default:
        return false;
    }

    if (success)
        refresh(_parent);

    return success;
}

/*!
  Returns the drop actions supported by this model.

  \sa Qt::DropActions
*/

Qt::DropActions ResourceModel::supportedDropActions() const
{
    return Qt::CopyAction | Qt::MoveAction; // FIXME: LinkAction is not supported yet
}

/*!
  Sets the name \a filters for the directory model.
*/

void ResourceModel::setNameFilters(const QStringList &filters)
{
    Q_D(ResourceModel);
    d->nameFilters = filters;
    emit layoutAboutToBeChanged();
    if (d->shouldStat)
       refresh(QModelIndex());
    else
        d->invalidate();
    emit layoutChanged();
}

/*!
  Returns a list of filters applied to the names in the model.
*/

QStringList ResourceModel::nameFilters() const
{
    Q_D(const ResourceModel);
    return d->nameFilters;
}

/*!
  Sets the directory model's filter to that specified by \a filters.

  Note that the filter you set should always include the QDir::AllDirs enum value,
  otherwise ResourceModel won't be able to read the directory structure.

  \sa QDir::Filters
*/

void ResourceModel::setFilter(QDir::Filters filters)
{
    Q_D(ResourceModel);
    d->filters = filters;
    emit layoutAboutToBeChanged();
    if (d->shouldStat)
        refresh(QModelIndex());
    else
        d->invalidate();
    emit layoutChanged();
}

/*!
  Returns the filter specification for the directory model.

  \sa QDir::Filters
*/

QDir::Filters ResourceModel::filter() const
{
    Q_D(const ResourceModel);
    return d->filters;
}

/*!
  Sets the directory model's sorting order to that specified by \a sort.

  \sa QDir::SortFlags
*/

void ResourceModel::setSorting(QDir::SortFlags sort)
{
    Q_D(ResourceModel);
    d->sort = sort;
    emit layoutAboutToBeChanged();
    if (d->shouldStat)
        refresh(QModelIndex());
    else
        d->invalidate();
    emit layoutChanged();
}

/*!
  Returns the sorting method used for the directory model.

  \sa QDir::SortFlags */

QDir::SortFlags ResourceModel::sorting() const
{
    Q_D(const ResourceModel);
    return d->sort;
}

/*!
    \property ResourceModel::resolveSymlinks
    \brief Whether the directory model should resolve symbolic links

    This is only relevant on operating systems that support symbolic
    links.
*/
void ResourceModel::setResolveSymlinks(bool enable)
{
    Q_D(ResourceModel);
    d->resolveSymlinks = enable;
}

bool ResourceModel::resolveSymlinks() const
{
    Q_D(const ResourceModel);
    return d->resolveSymlinks;
}

/*!
  \property ResourceModel::readOnly
  \brief Whether the directory model allows writing to the file system

  If this property is set to false, the directory model will allow renaming, copying
  and deleting of files and directories.

  This property is true by default
*/

void ResourceModel::setReadOnly(bool enable)
{
    Q_D(ResourceModel);
    d->readOnly = enable;
}

bool ResourceModel::isReadOnly() const
{
    Q_D(const ResourceModel);
    return d->readOnly;
}

/*!
  \property ResourceModel::lazyChildCount
  \brief Whether the directory model optimizes the hasChildren function
  to only check if the item is a directory.

  If this property is set to false, the directory model will make sure that a directory
  actually containes any files before reporting that it has children.
  Otherwise the directory model will report that an item has children if the item
  is a directory.

  This property is false by default
*/

void ResourceModel::setLazyChildCount(bool enable)
{
    Q_D(ResourceModel);
    d->lazyChildCount = enable;
}

bool ResourceModel::lazyChildCount() const
{
    Q_D(const ResourceModel);
    return d->lazyChildCount;
}

/*!
  ResourceModel caches file information. This function updates the
  cache. The \a parent parameter is the directory from which the
  model is updated; the default value will update the model from
  root directory of the file system (the entire model).
*/

void ResourceModel::refresh(const QModelIndex &parent)
{
    Q_D(ResourceModel);

    ResourceModelPrivate::QDirNode *n = d->indexValid(parent) ? d->node(parent) : &(d->root);

    int rows = n->children.count();
    if (rows == 0) {
        emit layoutAboutToBeChanged();
        n->stat = true; // make sure that next time we read all the info
        n->populated = false;
        emit layoutChanged();
        return;
    }

    beginResetModel();
//     emit layoutAboutToBeChanged();
    d->savePersistentIndexes();
//     d->rowsAboutToBeRemoved(parent, 0, rows - 1);
    n->stat = true; // make sure that next time we read all the info
    d->clear(n);
//     d->rowsRemoved(parent, 0, rows - 1);
    d->restorePersistentIndexes();
//     emit layoutChanged();
    endResetModel();
}

/*!
    \overload

    Returns the model item index for the given \a path.
*/

QModelIndex ResourceModel::index(const QString &path, int column) const
{
    Q_D(const ResourceModel);

    if (path.isEmpty() || path == QCoreApplication::translate("QFileDialog", "My Computer"))
        return QModelIndex();

    QString absolutePath = QDir(path).absolutePath();
#if (defined(Q_OS_WIN) && !defined(Q_OS_WINCE)) || defined(Q_OS_SYMBIAN)
    absolutePath = absolutePath.toLower();
#endif
#if defined(Q_OS_WIN) && !defined(Q_OS_WINCE)
    // On Windows, "filename......." and "filename" are equivalent
    if (absolutePath.endsWith(QLatin1Char('.'))) {
        int i;
        for (i = absolutePath.count() - 1; i >= 0; --i) {
            if (absolutePath.at(i) != QLatin1Char('.'))
                break;
        }
        absolutePath = absolutePath.left(i+1);
    }
#endif

#if QT_VERSION < QT_VERSION_CHECK(5, 14, 0)
    QStringList pathElements = absolutePath.split(QLatin1Char('/'), QString::SkipEmptyParts);
#else
    QStringList pathElements = absolutePath.split(QLatin1Char('/'), Qt::SkipEmptyParts);
#endif
    if ((pathElements.isEmpty() || !QFileInfo(path).exists())
#if !defined(Q_OS_WIN) || defined(Q_OS_WINCE)
        && path != QLatin1String("/")
#endif
        )
        return QModelIndex();

    QModelIndex idx; // start with "My Computer"
    if (!d->root.populated) // make sure the root is populated
        d->populate(&d->root);

#if defined(Q_OS_WIN) && !defined(Q_OS_WINCE)
    if (absolutePath.startsWith(QLatin1String("//"))) { // UNC path
        QString host = pathElements.first();
        int r = 0;
        for (; r < d->root.children.count(); ++r)
            if (d->root.children.at(r).info.fileName() == host)
                break;
        bool childAppended = false;
        if (r >= d->root.children.count() && d->allowAppendChild) {
            d->appendChild(&d->root, QLatin1String("//") + host);
            childAppended = true;
        }
        idx = index(r, 0, QModelIndex());
        pathElements.pop_front();
        if (childAppended)
            emit const_cast<ResourceModel*>(this)->layoutChanged();
    } else
#endif
#if (defined(Q_OS_WIN) && !defined(Q_OS_WINCE)) || defined(Q_OS_SYMBIAN)
    if (pathElements.at(0).endsWith(QLatin1Char(':'))) {
        pathElements[0] += QLatin1Char('/');
    }
#else
    // add the "/" item, since it is a valid path element on unix
    pathElements.prepend(QLatin1String("/"));
#endif

    for (int i = 0; i < pathElements.count(); ++i) {
        Q_ASSERT(!pathElements.at(i).isEmpty());
        QString element = pathElements.at(i);
        ResourceModelPrivate::QDirNode *parent = (idx.isValid() ? d->node(idx) : &d->root);

        Q_ASSERT(parent);
        if (!parent->populated)
            d->populate(parent);

        // search for the element in the child nodes first
        int row = -1;
        for (int j = parent->children.count() - 1; j >= 0; --j) {
            const QFileInfo& fi = parent->children.at(j).info;
            QString childFileName;
            childFileName = idx.isValid() ? fi.fileName() : fi.absoluteFilePath();
#if (defined(Q_OS_WIN) && !defined(Q_OS_WINCE)) || defined(Q_OS_SYMBIAN)
            childFileName = childFileName.toLower();
#endif
            if (childFileName == element) {
                if (i == pathElements.count() - 1)
                    parent->children[j].stat = true;
                row = j;
                break;
            }
        }

        // we couldn't find the path element, we create a new node since we _know_ that the path is valid
        if (row == -1) {
#if defined(Q_OS_WINCE)
            QString newPath;
            if (parent->info.isRoot())
                newPath = parent->info.absoluteFilePath() + element;
            else
                newPath = parent->info.absoluteFilePath() + QLatin1Char('/') + element;
#else
            QString newPath = parent->info.absoluteFilePath() + QLatin1Char('/') + element;
#endif
            if (!d->allowAppendChild || !QFileInfo(newPath).isDir())
                return QModelIndex();
            d->appendChild(parent, newPath);
            row = parent->children.count() - 1;
            if (i == pathElements.count() - 1) // always stat children of  the last element
                parent->children[row].stat = true;
            emit const_cast<ResourceModel*>(this)->layoutChanged();
        }

        Q_ASSERT(row >= 0);
        idx = createIndex(row, 0, static_cast<void*>(&parent->children[row]));
        Q_ASSERT(idx.isValid());
    }

    if (column != 0)
        return idx.sibling(idx.row(), column);
    return idx;
}

/*!
  Returns true if the model item \a index represents a directory;
  otherwise returns false.
*/

bool ResourceModel::isDir(const QModelIndex &index) const
{
    Q_D(const ResourceModel);
    Q_ASSERT(d->indexValid(index));
    ResourceModelPrivate::QDirNode *node = d->node(index);
    return node->info.isDir();
}

/*!
  Create a directory with the \a name in the \a parent model item.
*/

QModelIndex ResourceModel::mkdir(const QModelIndex &parent, const QString &name)
{
    Q_D(ResourceModel);
    if (!d->indexValid(parent) || isReadOnly())
        return QModelIndex();

    ResourceModelPrivate::QDirNode *p = d->node(parent);
    QString path = p->info.absoluteFilePath();
    // For the indexOf() method to work, the new directory has to be a direct child of
    // the parent directory.

    QDir newDir(name);
    QDir dir(path);
    if (newDir.isRelative())
        newDir = QDir(path + QLatin1Char('/') + name);
    QString childName = newDir.dirName(); // Get the singular name of the directory
    newDir.cdUp();

    if (newDir.absolutePath() != dir.absolutePath() || !dir.mkdir(name))
        return QModelIndex(); // nothing happened

    refresh(parent);

    QStringList entryList = d->entryList(path);
    int r = entryList.indexOf(childName);
    QModelIndex i = index(r, 0, parent); // return an invalid index

    return i;
}

/*!
  Removes the directory corresponding to the model item \a index in the
  directory model and \bold{deletes the corresponding directory from the
  file system}, returning true if successful. If the directory cannot be
  removed, false is returned.

  \warning This function deletes directories from the file system; it does
  \bold{not} move them to a location where they can be recovered.

  \sa remove()
*/

bool ResourceModel::rmdir(const QModelIndex &index)
{
    Q_D(ResourceModel);
    if (!d->indexValid(index) || isReadOnly())
        return false;

    ResourceModelPrivate::QDirNode *n = d_func()->node(index);
    if (!n->info.isDir()) {
        qWarning("rmdir: the node is not a directory");
        return false;
    }

    QModelIndex par = parent(index);
    ResourceModelPrivate::QDirNode *p = d_func()->node(par);
    QDir dir = p->info.dir(); // parent dir
    QString path = n->info.absoluteFilePath();
    if (!dir.rmdir(path))
        return false;

    refresh(par);

    return true;
}

/*!
  Removes the model item \a index from the directory model and \bold{deletes the
  corresponding file from the file system}, returning true if successful. If the
  item cannot be removed, false is returned.

  \warning This function deletes files from the file system; it does \bold{not}
  move them to a location where they can be recovered.

  \sa rmdir()
*/

bool ResourceModel::remove(const QModelIndex &index)
{
    Q_D(ResourceModel);
    if (!d->indexValid(index) || isReadOnly())
        return false;

    ResourceModelPrivate::QDirNode *n = d_func()->node(index);
    if (n->info.isDir())
        return false;

    QModelIndex par = parent(index);
    ResourceModelPrivate::QDirNode *p = d_func()->node(par);
    QDir dir = p->info.dir(); // parent dir
    QString path = n->info.absoluteFilePath();
    if (!dir.remove(path))
        return false;

    refresh(par);

    return true;
}

/*!
  Returns the path of the item stored in the model under the
  \a index given.

*/

QString ResourceModel::filePath(const QModelIndex &index) const
{
    Q_D(const ResourceModel);
    if (d->indexValid(index)) {
        QFileInfo fi = fileInfo(index);
        if (d->resolveSymlinks && fi.isSymLink())
            fi = d->resolvedInfo(fi);
        return QDir::cleanPath(fi.absoluteFilePath());
    }
    return QString(); // root path
}

/*!
  Returns the name of the item stored in the model under the
  \a index given.

*/

QString ResourceModel::fileName(const QModelIndex &index) const
{
    Q_D(const ResourceModel);
    if (!d->indexValid(index))
        return QString();
    QFileInfo info = fileInfo(index);
    if (info.isRoot())
        return info.absoluteFilePath();
    if (d->resolveSymlinks && info.isSymLink())
        info = d->resolvedInfo(info);
    return info.fileName();
}

/*!
  Returns the file information for the specified model \a index.

  \bold{Note:} If the model index represents a symbolic link in the
  underlying filing system, the file information returned will contain
  information about the symbolic link itself, regardless of whether
  resolveSymlinks is enabled or not.

  \sa QFileInfo::symLinkTarget()
*/

QFileInfo ResourceModel::fileInfo(const QModelIndex &index) const
{
    Q_D(const ResourceModel);
    Q_ASSERT(d->indexValid(index));

    ResourceModelPrivate::QDirNode *node = d->node(index);
    return node->info;
}

/*!
  \fn QObject *ResourceModel::parent() const
  \internal
*/

/*
  The root node is never seen outside the model.
*/

void ResourceModelPrivate::init()
{
    filters = QDir::AllEntries | QDir::NoDotAndDotDot;
    sort = QDir::Name;
    nameFilters << QLatin1String("*");
    root.parent = nullptr;
    root.info = QFileInfo(":");
    clear(&root);
}

QHash<int, QByteArray> ResourceModel::roleNames() const
{
    QHash<int, QByteArray> roles = QAbstractItemModel::roleNames();
    roles.insert(ResourceModel::FilePathRole, "filePath");
    roles.insert(ResourceModel::FileNameRole, "fileName");
    return roles;
}

ResourceModelPrivate::QDirNode *ResourceModelPrivate::node(int row, QDirNode *parent) const
{
    if (row < 0)
	return nullptr;

    bool isDir = !parent || parent->info.isDir();
    QDirNode *p = (parent ? parent : &root);
    if (isDir && !p->populated)
        populate(p); // will also resolve symlinks

    if (row >= p->children.count()) {
        qWarning("node: the row does not exist");
        return nullptr;
    }

    return const_cast<QDirNode*>(&p->children.at(row));
}

QVector<ResourceModelPrivate::QDirNode> ResourceModelPrivate::children(QDirNode *parent, bool stat) const
{
    Q_ASSERT(parent);
    QFileInfoList infoList;
    if (parent == &root) {
        parent = nullptr;
        infoList.append(root.info);
    } else if (parent->info.isDir()) {
        //resolve directory links only if requested.
        if (parent->info.isSymLink() && resolveSymlinks) {
            QString link = parent->info.symLinkTarget();
            if (link.size() > 1 && link.at(link.size() - 1) == QDir::separator())
                link.chop(1);
            if (stat)
                infoList = entryInfoList(link);
            else
                infoList = QDir(link).entryInfoList(nameFilters, QDir::AllEntries | QDir::System);
        } else {
            if (stat)
                infoList = entryInfoList(parent->info.absoluteFilePath());
            else
                infoList = QDir(parent->info.absoluteFilePath()).entryInfoList(nameFilters, QDir::AllEntries | QDir::System);
        }
    }

    QVector<QDirNode> nodes(infoList.count());
    for (int i = 0; i < infoList.count(); ++i) {
        QDirNode &node = nodes[i];
        node.parent = parent;
        node.info = infoList.at(i);
        node.populated = false;
        node.stat = shouldStat;
    }

    return nodes;
}

void ResourceModelPrivate::_q_refresh()
{
    Q_Q(ResourceModel);
    q->refresh(toBeRefreshed);
    toBeRefreshed = QModelIndex();
}

void ResourceModelPrivate::savePersistentIndexes()
{
//    Q_Q(ResourceModel);
    savedPersistent.clear();
//     foreach (QPersistentModelIndexData *data, q->persistentIndexes()) {
//         SavedPersistent saved;
//         QModelIndex index = data->index;
//         saved.path = q->filePath(index);
//         saved.column = index.column();
//         saved.data = data;
//         saved.index = index;
//         savedPersistent.append(saved);
//     }
}

void ResourceModelPrivate::restorePersistentIndexes()
{
//    Q_Q(ResourceModel);
//     bool allow = allowAppendChild;
//     allowAppendChild = false;
//     for (int i = 0; i < savedPersistent.count(); ++i) {
//         QPersistentModelIndexData *data = savedPersistent.at(i).data;
//         QString path = savedPersistent.at(i).path;
//         int column = savedPersistent.at(i).column;
//         QModelIndex idx = q->index(path, column);
//         if (idx != data->index || data->model == 0) {
//             //data->model may be equal to 0 if the model is getting destroyed
//             persistent.indexes.remove(data->index);
//             data->index = idx;
//             data->model = q;
//             if (idx.isValid())
//                 persistent.indexes.insert(idx, data);
//         }
//     }
    savedPersistent.clear();
//     allowAppendChild = allow;
}

QFileInfoList ResourceModelPrivate::entryInfoList(const QString &path) const
{
    const QDir dir(path);
    return dir.entryInfoList(nameFilters, filters, sort);
}

QStringList ResourceModelPrivate::entryList(const QString &path) const
{
    const QDir dir(path);
    return dir.entryList(nameFilters, filters, sort);
}

QString ResourceModelPrivate::name(const QModelIndex &index) const
{
    const QDirNode *n = node(index);
    const QFileInfo info = n->info;
    if (info.isRoot()) {
        QString name = info.absoluteFilePath();
#if defined(Q_OS_WIN) && !defined(Q_OS_WINCE)
        if (name.startsWith(QLatin1Char('/'))) // UNC host
            return info.fileName();
#endif
#if (defined(Q_OS_WIN) && !defined(Q_OS_WINCE)) || defined(Q_OS_SYMBIAN)
        if (name.endsWith(QLatin1Char('/')))
            name.chop(1);
#endif
        return name;
    }
    return info.fileName();
}

QString ResourceModelPrivate::size(const QModelIndex &index) const
{
    const QDirNode *n = node(index);
    if (n->info.isDir()) {
#ifdef Q_OS_MAC
        return QLatin1String("--");
#else
        return QLatin1String("");
#endif
    // Windows   - ""
    // OS X      - "--"
    // Konqueror - "4 KB"
    // Nautilus  - "9 items" (the number of children)
    }

    // According to the Si standard KB is 1000 bytes, KiB is 1024
    // but on windows sizes are calulated by dividing by 1024 so we do what they do.
    const quint64 kb = 1024;
    const quint64 mb = 1024 * kb;
    const quint64 gb = 1024 * mb;
    const quint64 tb = 1024 * gb;
    quint64 bytes = n->info.size();
    if (bytes >= tb)
        return ResourceModel::tr("%1 TB").arg(QLocale().toString(qreal(bytes) / tb, 'f', 3));
    if (bytes >= gb)
        return ResourceModel::tr("%1 GB").arg(QLocale().toString(qreal(bytes) / gb, 'f', 2));
    if (bytes >= mb)
        return ResourceModel::tr("%1 MB").arg(QLocale().toString(qreal(bytes) / mb, 'f', 1));
    if (bytes >= kb)
        return ResourceModel::tr("%1 KB").arg(QLocale().toString(bytes / kb));
    return ResourceModel::tr("%1 byte(s)").arg(QLocale().toString(bytes));
}

QString ResourceModelPrivate::type(const QModelIndex &index) const
{
  // poor interpolation of what QFileIconProvider::type() did
  // TODO: for Qt5 QMimeType might actually be a better choice here
  if (!index.parent().isValid())
    return ResourceModel::tr("Root");
  if (node(index)->info.isDir())
    return ResourceModel::tr("Folder");
  return ResourceModel::tr("%1 File").arg(node(index)->info.suffix());
}

QString ResourceModelPrivate::time(const QModelIndex &index) const
{
#ifndef QT_NO_DATESTRING
    return QLocale().toString(node(index)->info.lastModified(), QLocale::ShortFormat);
#else
    Q_UNUSED(index);
    return QString();
#endif
}

void ResourceModelPrivate::appendChild(ResourceModelPrivate::QDirNode *parent, const QString &path) const
{
    ResourceModelPrivate::QDirNode node;
    node.populated = false;
    node.stat = shouldStat;
    node.parent = (parent == &root ? nullptr : parent);
    node.info = QFileInfo(path);
    node.info.setCaching(true);

    // The following append(node) may reallocate the vector, thus
    // we need to update the pointers to the childnodes parent.
    ResourceModelPrivate *that = const_cast<ResourceModelPrivate *>(this);
    that->savePersistentIndexes();
    parent->children.append(node);
    for (int i = 0; i < parent->children.count(); ++i) {
        QDirNode *childNode = &parent->children[i];
        for (int j = 0; j < childNode->children.count(); ++j)
            childNode->children[j].parent = childNode;
    }
    that->restorePersistentIndexes();
}

QFileInfo ResourceModelPrivate::resolvedInfo(QFileInfo info)
{
#ifdef Q_OS_WIN
    // On windows, we cannot create a shortcut to a shortcut.
    return QFileInfo(info.symLinkTarget());
#else
    QStringList paths;
    do {
        QFileInfo link(info.symLinkTarget());
        if (link.isRelative())
            info.setFile(info.absolutePath(), link.filePath());
        else
            info = link;
        if (paths.contains(info.absoluteFilePath()))
            return QFileInfo();
        paths.append(info.absoluteFilePath());
    } while (info.isSymLink());
    return info;
#endif
}

#include "moc_resourcemodel.cpp"
