qdirmodel.cpp

Go to the documentation of this file.

/****************************************************************************
**
** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the QtGui module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** 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 "qdirmodel.h"

#ifndef QT_NO_DIRMODEL
#include <qstack.h>
#include <qfile.h>
#include <qfilesystemmodel.h>
#include <qurl.h>
#include <qmime.h>
#include <qpair.h>
#include <qvector.h>
#include <qobject.h>
#include <qdatetime.h>
#include <qlocale.h>
#include <qstyle.h>
#include <qapplication.h>
#include <private/qabstractitemmodel_p.h>
#include <qdebug.h>

QT_BEGIN_NAMESPACE

class QDirModelPrivate : public QAbstractItemModelPrivate
{
    Q_DECLARE_PUBLIC(QDirModel)

public:
    struct QDirNode
    {
        QDirNode() : parent(0), populated(false), stat(false) {}
        ~QDirNode() { children.clear(); }
        QDirNode *parent;
        QFileInfo info;
        QIcon icon; // cache the icon
        mutable QVector<QDirNode> children;
        mutable bool populated; // have we read the children
        mutable bool stat;
    };

    QDirModelPrivate()
        : resolveSymlinks(true),
          readOnly(true),
          lazyChildCount(false),
          allowAppendChild(true),
          iconProvider(&defaultProvider),
          shouldStat(true) // ### This is set to false by QFileDialog
    { }

    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(QDirModelPrivate::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;

    QFileIconProvider *iconProvider;
    QFileIconProvider defaultProvider;

    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(QDirModelPrivate *modelPrivate)
{
    modelPrivate->shouldStat = false;
}

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

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

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

void QDirModelPrivate::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));
    }
}

QDirModel::QDirModel(const QStringList &nameFilters,
                     QDir::Filters filters,
                     QDir::SortFlags sort,
                     QObject *parent)
    : QAbstractItemModel(*new QDirModelPrivate, parent)
{
    Q_D(QDirModel);
    // we always start with QDir::drives()
    d->nameFilters = nameFilters.isEmpty() ? QStringList(QLatin1String("*")) : nameFilters;
    d->filters = filters;
    d->sort = sort;
    d->root.parent = 0;
    d->root.info = QFileInfo();
    d->clear(&d->root);
}

QDirModel::QDirModel(QObject *parent)
    : QAbstractItemModel(*new QDirModelPrivate, parent)
{
    Q_D(QDirModel);
    d->init();
}

QDirModel::QDirModel(QDirModelPrivate &dd, QObject *parent)
    : QAbstractItemModel(dd, parent)
{
    Q_D(QDirModel);
    d->init();
}

QDirModel::~QDirModel()
{

}

QModelIndex QDirModel::index(int row, int column, const QModelIndex &parent) const
{
    Q_D(const QDirModel);
    // 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
    QDirModelPrivate::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
    QDirModelPrivate::QDirNode *n = d->node(row, d->indexValid(parent) ? p : 0);
    Q_ASSERT(n);

    return createIndex(row, column, n);
}

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

    if (!d->indexValid(child))
    return QModelIndex();
    QDirModelPrivate::QDirNode *node = d->node(child);
    QDirModelPrivate::QDirNode *par = (node ? node->parent : 0);
    if (par == 0) // parent is the root node
    return QModelIndex();

    // get the parent's row
    const QVector<QDirModelPrivate::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);
}

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

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

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

QVariant QDirModel::data(const QModelIndex &index, int role) const
{
    Q_D(const QDirModel);
    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 == FileIconRole)
            return fileIcon(index);
        if (role == FilePathRole)
            return filePath(index);
        if (role == FileNameRole)
            return fileName(index);
    }

    if (index.column() == 1 && Qt::TextAlignmentRole == role) {
        return Qt::AlignRight;
    }
    return QVariant();
}

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

    QDirModelPrivate::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;
}

QVariant QDirModel::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);
}

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

    if (!parent.isValid()) // the invalid index is the "My Computer" item
        return true; // the drives
    QDirModelPrivate::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;
}

Qt::ItemFlags QDirModel::flags(const QModelIndex &index) const
{
    Q_D(const QDirModel);
    Qt::ItemFlags flags = QAbstractItemModel::flags(index);
    if (!d->indexValid(index))
        return flags;
    flags |= Qt::ItemIsDragEnabled;
    if (d->readOnly)
        return flags;
    QDirModelPrivate::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;
}

void QDirModel::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);
}

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

QMimeData *QDirModel::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));
    QMimeData *data = new QMimeData();
    data->setUrls(urls);
    return data;
}

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

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

    QList<QUrl> urls = data->urls();
    QList<QUrl>::const_iterator 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;
}

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

void QDirModel::setIconProvider(QFileIconProvider *provider)
{
    Q_D(QDirModel);
    d->iconProvider = provider;
}

QFileIconProvider *QDirModel::iconProvider() const
{
    Q_D(const QDirModel);
    return d->iconProvider;
}

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

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

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

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

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

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

void QDirModel::setResolveSymlinks(bool enable)
{
    Q_D(QDirModel);
    d->resolveSymlinks = enable;
}

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

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

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

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

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

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

    QDirModelPrivate::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;
    }

    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();
}

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

    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

    QStringList pathElements = absolutePath.split(QLatin1Char('/'), QString::SkipEmptyParts);
    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<QDirModel*>(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);
        QDirModelPrivate::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<QDirModel*>(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;
}

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

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

    QDirModelPrivate::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;
}

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

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

    QModelIndex par = parent(index);
    QDirModelPrivate::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;
}

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

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

    QModelIndex par = parent(index);
    QDirModelPrivate::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;
}

QString QDirModel::filePath(const QModelIndex &index) const
{
    Q_D(const QDirModel);
    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
}

QString QDirModel::fileName(const QModelIndex &index) const
{
    Q_D(const QDirModel);
    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();
}

QIcon QDirModel::fileIcon(const QModelIndex &index) const
{
    Q_D(const QDirModel);
    if (!d->indexValid(index))
        return d->iconProvider->icon(QFileIconProvider::Computer);
    QDirModelPrivate::QDirNode *node = d->node(index);
    if (node->icon.isNull())
        node->icon = d->iconProvider->icon(node->info);
    return node->icon;
}

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

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

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

void QDirModelPrivate::init()
{
    Q_Q(QDirModel);
    filters = QDir::AllEntries | QDir::NoDotAndDotDot;
    sort = QDir::Name;
    nameFilters << QLatin1String("*");
    root.parent = 0;
    root.info = QFileInfo();
    clear(&root);
    QHash<int, QByteArray> roles = q->roleNames();
    roles.insertMulti(QDirModel::FileIconRole, "fileIcon"); // == Qt::decoration
    roles.insert(QDirModel::FilePathRole, "filePath");
    roles.insert(QDirModel::FileNameRole, "fileName");
    q->setRoleNames(roles);
}

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

    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 0;
    }

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

QVector<QDirModelPrivate::QDirNode> QDirModelPrivate::children(QDirNode *parent, bool stat) const
{
    Q_ASSERT(parent);
    QFileInfoList infoList;
    if (parent == &root) {
        parent = 0;
        infoList = QDir::drives();
    } 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 QDirModelPrivate::_q_refresh()
{
    Q_Q(QDirModel);
    q->refresh(toBeRefreshed);
    toBeRefreshed = QModelIndex();
}

void QDirModelPrivate::savePersistentIndexes()
{
    Q_Q(QDirModel);
    savedPersistent.clear();
    foreach (QPersistentModelIndexData *data, persistent.indexes) {
        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 QDirModelPrivate::restorePersistentIndexes()
{
    Q_Q(QDirModel);
    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 QDirModelPrivate::entryInfoList(const QString &path) const
{
    const QDir dir(path);
    return dir.entryInfoList(nameFilters, filters, sort);
}

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

QString QDirModelPrivate::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 QDirModelPrivate::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 QFileSystemModel::tr("%1 TB").arg(QLocale().toString(qreal(bytes) / tb, 'f', 3));
    if (bytes >= gb)
        return QFileSystemModel::tr("%1 GB").arg(QLocale().toString(qreal(bytes) / gb, 'f', 2));
    if (bytes >= mb)
        return QFileSystemModel::tr("%1 MB").arg(QLocale().toString(qreal(bytes) / mb, 'f', 1));
    if (bytes >= kb)
        return QFileSystemModel::tr("%1 KB").arg(QLocale().toString(bytes / kb));
    return QFileSystemModel::tr("%1 byte(s)").arg(QLocale().toString(bytes));
}

QString QDirModelPrivate::type(const QModelIndex &index) const
{
    return iconProvider->type(node(index)->info);
}

QString QDirModelPrivate::time(const QModelIndex &index) const
{
#ifndef QT_NO_DATESTRING
    return node(index)->info.lastModified().toString(Qt::LocalDate);
#else
    Q_UNUSED(index);
    return QString();
#endif
}

void QDirModelPrivate::appendChild(QDirModelPrivate::QDirNode *parent, const QString &path) const
{
    QDirModelPrivate::QDirNode node;
    node.populated = false;
    node.stat = shouldStat;
    node.parent = (parent == &root ? 0 : 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.
    QDirModelPrivate *that = const_cast<QDirModelPrivate *>(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 QDirModelPrivate::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
}

QT_END_NAMESPACE

#include "moc_qdirmodel.cpp"

#endif // QT_NO_DIRMODEL