/* $Id: QIFileDialog.cpp $ */
/** @file
 *
 * VBox frontends: Qt GUI ("VirtualBox"):
 * Qt extensions: QIFileDialog class implementation
 */

/*
 * Copyright (C) 2009 Oracle Corporation
 *
 * This file is part of VirtualBox Open Source Edition (OSE), as
 * available from http://www.virtualbox.org. This file is free software;
 * you can redistribute it and/or modify it under the terms of the GNU
 * General Public License (GPL) as published by the Free Software
 * Foundation, in version 2 as it comes in the "COPYING" file of the
 * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
 * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
 */

/* VBox includes */
#include "VBoxGlobal.h"
#include "QIFileDialog.h"

#if defined Q_WS_WIN

/// @todo bird: Use (U)INT_PTR, (U)LONG_PTR, DWORD_PTR, or (u)intptr_t.
#if defined Q_OS_WIN64
typedef unsigned __int64 Q_ULONG;   /* word up to 64 bit unsigned */
#else
typedef unsigned long Q_ULONG;      /* word up to 64 bit unsigned */
#endif

/* Qt includes */
#include <QEvent>
#include <QEventLoop>
#include <QThread>

/* WinAPI includes */
#include "shlobj.h"

static QString extractFilter (const QString &aRawFilter)
{
    static const char qt_file_dialog_filter_reg_exp[] =
        "([a-zA-Z0-9 ]*)\\(([a-zA-Z0-9_.*? +;#\\[\\]]*)\\)$";

    QString result = aRawFilter;
    QRegExp r (QString::fromLatin1 (qt_file_dialog_filter_reg_exp));
    int index = r.indexIn (result);
    if (index >= 0)
        result = r.cap (2);
    return result.replace (QChar (' '), QChar (';'));
}

/**
 * Converts QFileDialog filter list to Win32 API filter list.
 */
static QString winFilter (const QString &aFilter)
{
    QStringList filterLst;

    if (!aFilter.isEmpty())
    {
        int i = aFilter.indexOf (";;", 0);
        QString sep (";;");
        if (i == -1)
        {
            if (aFilter.indexOf ("\n", 0) != -1)
            {
                sep = "\n";
                i = aFilter.indexOf (sep, 0);
            }
        }

        filterLst = aFilter.split (sep);
    }

    QStringList::Iterator it = filterLst.begin();
    QString winfilters;
    for (; it != filterLst.end(); ++ it)
    {
        winfilters += *it;
        winfilters += QChar::Null;
        winfilters += extractFilter (*it);
        winfilters += QChar::Null;
    }
    winfilters += QChar::Null;
    return winfilters;
}

/*
 * Callback function to control the native Win32 API file dialog
 */
UINT_PTR CALLBACK OFNHookProc (HWND aHdlg, UINT aUiMsg, WPARAM aWParam, LPARAM aLParam)
{
    if (aUiMsg == WM_NOTIFY)
    {
        OFNOTIFY *notif = (OFNOTIFY*) aLParam;
        if (notif->hdr.code == CDN_TYPECHANGE)
        {
            /* locate native dialog controls */
            HWND parent = GetParent (aHdlg);
            HWND button = GetDlgItem (parent, IDOK);
            HWND textfield = ::GetDlgItem (parent, cmb13);
            if (textfield == NULL)
                textfield = ::GetDlgItem (parent, edt1);
            if (textfield == NULL)
                return FALSE;
            HWND selector = ::GetDlgItem (parent, cmb1);

            /* simulate filter change by pressing apply-key */
            int    size = 256;
            TCHAR *buffer = (TCHAR*)malloc (size);
            SendMessage (textfield, WM_GETTEXT, size, (LPARAM)buffer);
            SendMessage (textfield, WM_SETTEXT, 0, (LPARAM)"\0");
            SendMessage (button, BM_CLICK, 0, 0);
            SendMessage (textfield, WM_SETTEXT, 0, (LPARAM)buffer);
            free (buffer);

            /* make request for focus moving to filter selector combo-box */
            HWND curFocus = GetFocus();
            PostMessage (curFocus, WM_KILLFOCUS, (WPARAM)selector, 0);
            PostMessage (selector, WM_SETFOCUS, (WPARAM)curFocus, 0);
            WPARAM wParam = MAKEWPARAM (WA_ACTIVE, 0);
            PostMessage (selector, WM_ACTIVATE, wParam, (LPARAM)curFocus);
        }
    }
    return FALSE;
}

/*
 * Callback function to control the native Win32 API folders dialog
 */
static int __stdcall winGetExistDirCallbackProc (HWND hwnd, UINT uMsg,
                                                 LPARAM lParam, LPARAM lpData)
{
    if (uMsg == BFFM_INITIALIZED && lpData != 0)
    {
        QString *initDir = (QString *)(lpData);
        if (!initDir->isEmpty())
        {
            SendMessage (hwnd, BFFM_SETSELECTION, TRUE, Q_ULONG (
                initDir->isNull() ? 0 : initDir->utf16()));
        }
    }
    else if (uMsg == BFFM_SELCHANGED)
    {
        TCHAR path [MAX_PATH];
        SHGetPathFromIDList (LPITEMIDLIST (lParam), path);
        QString tmpStr = QString::fromUtf16 ((ushort*)path);
        if (!tmpStr.isEmpty())
            SendMessage (hwnd, BFFM_ENABLEOK, 1, 1);
        else
            SendMessage (hwnd, BFFM_ENABLEOK, 0, 0);
        SendMessage (hwnd, BFFM_SETSTATUSTEXT, 1, Q_ULONG (path));
    }
    return 0;
}

/**
 *  QEvent class to carry Win32 API native dialog's result information
 */
class OpenNativeDialogEvent : public QEvent
{
public:

    OpenNativeDialogEvent (const QString &aResult, QEvent::Type aType)
        : QEvent (aType), mResult (aResult) {}

    const QString& result() { return mResult; }

private:

    QString mResult;
};

/**
 *  QObject class reimplementation which is the target for OpenNativeDialogEvent
 *  event. It receives OpenNativeDialogEvent event from another thread,
 *  stores result information and exits the given local event loop.
 */
class LoopObject : public QObject
{
    Q_OBJECT;

public:

    LoopObject (QEvent::Type aType, QEventLoop &aLoop)
        : mType (aType), mLoop (aLoop), mResult (QString::null) {}
    const QString& result() { return mResult; }

private:

    bool event (QEvent *aEvent)
    {
        if (aEvent->type() == mType)
        {
            OpenNativeDialogEvent *ev = (OpenNativeDialogEvent*) aEvent;
            mResult = ev->result();
            mLoop.quit();
            return true;
        }
        return QObject::event (aEvent);
    }

    QEvent::Type mType;
    QEventLoop &mLoop;
    QString mResult;
};

#endif /* Q_WS_WIN */

QIFileDialog::QIFileDialog (QWidget *aParent, Qt::WindowFlags aFlags)
    : QFileDialog (aParent, aFlags)
{
}

/**
 *  Reimplementation of QFileDialog::getExistingDirectory() that removes some
 *  oddities and limitations.
 *
 *  On Win32, this function makes sure a native dialog is launched in
 *  another thread to avoid dialog visualization errors occurring due to
 *  multi-threaded COM apartment initialization on the main UI thread while
 *  the appropriate native dialog function expects a single-threaded one.
 *
 *  On all other platforms, this function is equivalent to
 *  QFileDialog::getExistingDirectory().
 */
QString QIFileDialog::getExistingDirectory (const QString &aDir,
                                            QWidget *aParent,
                                            const QString &aCaption,
                                            bool aDirOnly,
                                            bool aResolveSymlinks)
{
#if defined Q_WS_WIN

    /**
     *  QEvent class reimplementation to carry Win32 API
     *  native dialog's result folder information
     */
    class GetExistDirectoryEvent : public OpenNativeDialogEvent
    {
    public:

        enum { TypeId = QEvent::User + 1 };

        GetExistDirectoryEvent (const QString &aResult)
            : OpenNativeDialogEvent (aResult, (QEvent::Type) TypeId) {}
    };

    /**
     *  QThread class reimplementation to open Win32 API
     *  native folder's dialog
     */
    class Thread : public QThread
    {
    public:

        Thread (QWidget *aParent, QObject *aTarget,
                const QString &aDir, const QString &aCaption)
            : mParent (aParent), mTarget (aTarget), mDir (aDir), mCaption (aCaption) {}

        virtual void run()
        {
            QString result;

            QWidget *topParent = mParent ? mParent->window() : vboxGlobal().mainWindow();
            QString title = mCaption.isNull() ? tr ("Select a directory") : mCaption;

            TCHAR path [MAX_PATH];
            path [0] = 0;
            TCHAR initPath [MAX_PATH];
            initPath [0] = 0;

            BROWSEINFO bi;
            bi.hwndOwner = topParent ? topParent->winId() : 0;
            bi.pidlRoot = 0;
            bi.lpszTitle = (TCHAR*)(title.isNull() ? 0 : title.utf16());
            bi.pszDisplayName = initPath;
            bi.ulFlags = BIF_RETURNONLYFSDIRS | BIF_STATUSTEXT | BIF_NEWDIALOGSTYLE;
            bi.lpfn = winGetExistDirCallbackProc;
            bi.lParam = Q_ULONG (&mDir);

            LPITEMIDLIST itemIdList = SHBrowseForFolder (&bi);
            if (itemIdList)
            {
                SHGetPathFromIDList (itemIdList, path);
                IMalloc *pMalloc;
                if (SHGetMalloc (&pMalloc) != NOERROR)
                    result = QString::null;
                else
                {
                    pMalloc->Free (itemIdList);
                    pMalloc->Release();
                    result = QString::fromUtf16 ((ushort*)path);
                }
            }
            else
                result = QString::null;
            QApplication::postEvent (mTarget, new GetExistDirectoryEvent (result));
        }

    private:

        QWidget *mParent;
        QObject *mTarget;
        QString mDir;
        QString mCaption;
    };

    /* Local event loop to run while waiting for the result from another
     * thread */
    QEventLoop loop;

    QString dir = QDir::toNativeSeparators (aDir);
    LoopObject loopObject ((QEvent::Type) GetExistDirectoryEvent::TypeId, loop);

    Thread openDirThread (aParent, &loopObject, dir, aCaption);
    openDirThread.start();
    loop.exec();
    openDirThread.wait();

    return loopObject.result();

#elif defined (Q_WS_X11) && (QT_VERSION < 0x040400)

    /* Here is workaround for Qt4.3 bug with QFileDialog which crushes when
     * gets initial path as hidden directory if no hidden files are shown.
     * See http://trolltech.com/developer/task-tracker/index_html?method=entry&id=193483
     * for details */
    QFileDialog dlg (aParent);
    dlg.setWindowTitle (aCaption);
    dlg.setDirectory (aDir);
    dlg.setResolveSymlinks (aResolveSymlinks);
    dlg.setFileMode (aDirOnly ? QFileDialog::DirectoryOnly : QFileDialog::Directory);
    QAction *hidden = dlg.findChild <QAction*> ("qt_show_hidden_action");
    if (hidden)
    {
        hidden->trigger();
        hidden->setVisible (false);
    }
    return dlg.exec() ? dlg.selectedFiles() [0] : QString::null;
#elif defined (Q_WS_MAC) && (QT_VERSION >= 0x040600)

    /* After 4.5 exec ignores the Qt::Sheet flag. See "New Ways of Using
     * Dialogs" in http://doc.trolltech.com/qq/QtQuarterly30.pdf why. Because
     * we are lazy, we recreate the old behavior. Unfortunately there is a bug
     * in Qt 4.5.x which result in showing the native & the Qt dialog at the
     * same time. */
    QFileDialog dlg (aParent, Qt::Sheet);
    dlg.setWindowTitle (aCaption);
    dlg.setDirectory (aDir);
    dlg.setResolveSymlinks (aResolveSymlinks);
    dlg.setFileMode (aDirOnly ? QFileDialog::DirectoryOnly : QFileDialog::Directory);

    QEventLoop eventLoop;
    QObject::connect(&dlg, SIGNAL(finished(int)),
                     &eventLoop, SLOT(quit()));
    /* Use the new open call. */
    dlg.open();
    eventLoop.exec();

    return dlg.result() == QDialog::Accepted ? dlg.selectedFiles() [0] : QString::null;

#else

    QFileDialog::Options o;
# if defined (Q_WS_X11)
    /** @todo see http://bugs.kde.org/show_bug.cgi?id=210904, make it conditional
     *        when this bug is fixed (xtracker 5167).
     *        Apparently not necessary anymore (xtracker 5748)! */
//    if (vboxGlobal().isKWinManaged())
//      o |= QFileDialog::DontUseNativeDialog;
# endif
    if (aDirOnly)
        o |= QFileDialog::ShowDirsOnly;
    if (!aResolveSymlinks)
        o |= QFileDialog::DontResolveSymlinks;
    return QFileDialog::getExistingDirectory (aParent, aCaption, aDir, o);

#endif
}

/**
 *  Reimplementation of QFileDialog::getSaveFileName() that removes some
 *  oddities and limitations.
 *
 *  On Win32, this function makes sure a file filter is applied automatically
 *  right after it is selected from the drop-down list, to conform to common
 *  experience in other applications. Note that currently, @a selectedFilter
 *  is always set to null on return.
 *
 *  On all other platforms, this function is equivalent to
 *  QFileDialog::getSaveFileName().
 */
/* static */
QString QIFileDialog::getSaveFileName (const QString &aStartWith,
                                       const QString &aFilters,
                                       QWidget       *aParent,
                                       const QString &aCaption,
                                       QString       *aSelectedFilter /* = 0 */,
                                       bool           aResolveSymlinks /* = true */)
{
#if defined Q_WS_WIN

    /**
     *  QEvent class reimplementation to carry Win32 API native dialog's
     *  result folder information
     */
    class GetOpenFileNameEvent : public OpenNativeDialogEvent
    {
    public:

        enum { TypeId = QEvent::User + 2 };

        GetOpenFileNameEvent (const QString &aResult)
            : OpenNativeDialogEvent (aResult, (QEvent::Type) TypeId) {}
    };

    /**
     *  QThread class reimplementation to open Win32 API native file dialog
     */
    class Thread : public QThread
    {
    public:

        Thread (QWidget *aParent, QObject *aTarget,
                const QString &aStartWith, const QString &aFilters,
                const QString &aCaption) :
                mParent (aParent), mTarget (aTarget),
                mStartWith (aStartWith), mFilters (aFilters),
                mCaption (aCaption) {}

        virtual void run()
        {
            QString result;

            QString workDir;
            QString initSel;
            QFileInfo fi (mStartWith);

            if (fi.isDir())
                workDir = mStartWith;
            else
            {
                workDir = fi.absolutePath();
                initSel = fi.fileName();
            }

            workDir = QDir::toNativeSeparators (workDir);
            if (!workDir.endsWith ("\\"))
                workDir += "\\";

            QString title = mCaption.isNull() ? tr ("Select a file") : mCaption;

            QWidget *topParent = mParent ? mParent->window() : vboxGlobal().mainWindow();
            QString winFilters = winFilter (mFilters);
            AssertCompile (sizeof (TCHAR) == sizeof (QChar));
            TCHAR buf [1024];
            if (initSel.length() > 0 && initSel.length() < sizeof (buf))
                memcpy (buf, initSel.isNull() ? 0 : initSel.utf16(),
                        (initSel.length() + 1) * sizeof (TCHAR));
            else
                buf [0] = 0;

            OPENFILENAME ofn;
            memset (&ofn, 0, sizeof (OPENFILENAME));

            ofn.lStructSize = sizeof (OPENFILENAME);
            ofn.hwndOwner = topParent ? topParent->winId() : 0;
            ofn.lpstrFilter = (TCHAR *) winFilters.isNull() ? 0 : winFilters.utf16();
            ofn.lpstrFile = buf;
            ofn.nMaxFile = sizeof (buf) - 1;
            ofn.lpstrInitialDir = (TCHAR *) workDir.isNull() ? 0 : workDir.utf16();
            ofn.lpstrTitle = (TCHAR *) title.isNull() ? 0 : title.utf16();
            ofn.Flags = (OFN_NOCHANGEDIR | OFN_HIDEREADONLY |
                         OFN_EXPLORER | OFN_ENABLEHOOK |
                         OFN_NOTESTFILECREATE);
            ofn.lpfnHook = OFNHookProc;

            if (GetSaveFileName (&ofn))
            {
                result = QString::fromUtf16 ((ushort *) ofn.lpstrFile);
            }

            // qt_win_eatMouseMove();
            MSG msg = {0, 0, 0, 0, 0, 0, 0};
            while (PeekMessage (&msg, 0, WM_MOUSEMOVE, WM_MOUSEMOVE, PM_REMOVE));
            if (msg.message == WM_MOUSEMOVE)
                PostMessage (msg.hwnd, msg.message, 0, msg.lParam);

            result = result.isEmpty() ? result : QFileInfo (result).absoluteFilePath();

            QApplication::postEvent (mTarget, new GetOpenFileNameEvent (result));
        }

    private:

        QWidget *mParent;
        QObject *mTarget;
        QString mStartWith;
        QString mFilters;
        QString mCaption;
    };

    if (aSelectedFilter)
        *aSelectedFilter = QString::null;

    /* Local event loop to run while waiting for the result from another
     * thread */
    QEventLoop loop;

    QString startWith = QDir::toNativeSeparators (aStartWith);
    LoopObject loopObject ((QEvent::Type) GetOpenFileNameEvent::TypeId, loop);

    if (aParent)
        aParent->setWindowModality (Qt::WindowModal);

    Thread openDirThread (aParent, &loopObject, startWith, aFilters, aCaption);
    openDirThread.start();
    loop.exec();
    openDirThread.wait();

    if (aParent)
        aParent->setWindowModality (Qt::NonModal);

    return loopObject.result();

#elif defined (Q_WS_X11) && (QT_VERSION < 0x040400)

    /* Here is workaround for Qt4.3 bug with QFileDialog which crushes when
     * gets initial path as hidden directory if no hidden files are shown.
     * See http://trolltech.com/developer/task-tracker/index_html?method=entry&id=193483
     * for details */
    QFileDialog dlg (aParent);
    dlg.setWindowTitle (aCaption);
    dlg.setDirectory (aStartWith);
    dlg.setFilter (aFilters);
    dlg.setFileMode (QFileDialog::QFileDialog::AnyFile);
    dlg.setAcceptMode (QFileDialog::AcceptSave);
    if (aSelectedFilter)
        dlg.selectFilter (*aSelectedFilter);
    dlg.setResolveSymlinks (aResolveSymlinks);
    dlg.setConfirmOverwrite (false);
    QAction *hidden = dlg.findChild <QAction*> ("qt_show_hidden_action");
    if (hidden)
    {
        hidden->trigger();
        hidden->setVisible (false);
    }
    return dlg.exec() == QDialog::Accepted ? dlg.selectedFiles().value (0, "") : QString::null;

#elif defined (Q_WS_MAC) && (QT_VERSION >= 0x040600)

    /* After 4.5 exec ignores the Qt::Sheet flag. See "New Ways of Using
     * Dialogs" in http://doc.trolltech.com/qq/QtQuarterly30.pdf why. Because
     * we are lazy, we recreate the old behavior. Unfortunately there is a bug
     * in Qt 4.5.x which result in showing the native & the Qt dialog at the
     * same time. */
    QFileDialog dlg (aParent);
    dlg.setWindowTitle (aCaption);
    dlg.setDirectory (aStartWith);
    dlg.setFilter (aFilters);
    dlg.setFileMode (QFileDialog::QFileDialog::AnyFile);
    dlg.setAcceptMode (QFileDialog::AcceptSave);
    if (aSelectedFilter)
        dlg.selectFilter (*aSelectedFilter);
    dlg.setResolveSymlinks (aResolveSymlinks);
    dlg.setConfirmOverwrite (false);

    QEventLoop eventLoop;
    QObject::connect(&dlg, SIGNAL(finished(int)),
                     &eventLoop, SLOT(quit()));
    /* Use the new open call. */
    dlg.open();
    eventLoop.exec();

    return dlg.result() == QDialog::Accepted ? dlg.selectedFiles().value (0, "") : QString::null;

#else

    QFileDialog::Options o;
# if defined (Q_WS_X11)
    /** @todo see http://bugs.kde.org/show_bug.cgi?id=210904, make it conditional
     *        when this bug is fixed (xtracker 5167)
     *        Apparently not necessary anymore (xtracker 5748)! */
//    if (vboxGlobal().isKWinManaged())
//      o |= QFileDialog::DontUseNativeDialog;
# endif
    if (!aResolveSymlinks)
        o |= QFileDialog::DontResolveSymlinks;
    o |= QFileDialog::DontConfirmOverwrite;
    return QFileDialog::getSaveFileName (aParent, aCaption, aStartWith,
                                         aFilters, aSelectedFilter, o);
#endif
}

/**
 *  Reimplementation of QFileDialog::getOpenFileName() that removes some
 *  oddities and limitations.
 *
 *  On Win32, this function makes sure a file filter is applied automatically
 *  right after it is selected from the drop-down list, to conform to common
 *  experience in other applications. Note that currently, @a selectedFilter
 *  is always set to null on return.
 *
 *  On all other platforms, this function is equivalent to
 *  QFileDialog::getOpenFileName().
 */
/* static */
QString QIFileDialog::getOpenFileName (const QString &aStartWith,
                                       const QString &aFilters,
                                       QWidget       *aParent,
                                       const QString &aCaption,
                                       QString       *aSelectedFilter /* = 0 */,
                                       bool           aResolveSymlinks /* = true */)
{
    return getOpenFileNames (aStartWith,
                             aFilters,
                             aParent,
                             aCaption,
                             aSelectedFilter,
                             aResolveSymlinks,
                             true /* aSingleFile */).value (0, "");
}

/**
 *  Reimplementation of QFileDialog::getOpenFileNames() that removes some
 *  oddities and limitations.
 *
 *  On Win32, this function makes sure a file filter is applied automatically
 *  right after it is selected from the drop-down list, to conform to common
 *  experience in other applications. Note that currently, @a selectedFilter
 *  is always set to null on return.
 *  @todo: implement the multiple file selection on win
 *  @todo: is this extra handling on win still necessary with Qt4?
 *
 *  On all other platforms, this function is equivalent to
 *  QFileDialog::getOpenFileNames().
 */
/* static */
QStringList QIFileDialog::getOpenFileNames (const QString &aStartWith,
                                            const QString &aFilters,
                                            QWidget       *aParent,
                                            const QString &aCaption,
                                            QString       *aSelectedFilter /* = 0 */,
                                            bool           aResolveSymlinks /* = true */,
                                            bool           aSingleFile /* = false */)
{
/* It seems, running QFileDialog in separate thread is NOT needed under windows any more: */
#if defined (Q_WS_WIN) && (QT_VERSION < 0x040403)

    /**
     *  QEvent class reimplementation to carry Win32 API native dialog's
     *  result folder information
     */
    class GetOpenFileNameEvent : public OpenNativeDialogEvent
    {
    public:

        enum { TypeId = QEvent::User + 3 };

        GetOpenFileNameEvent (const QString &aResult)
            : OpenNativeDialogEvent (aResult, (QEvent::Type) TypeId) {}
    };

    /**
     *  QThread class reimplementation to open Win32 API native file dialog
     */
    class Thread : public QThread
    {
    public:

        Thread (QWidget *aParent, QObject *aTarget,
                const QString &aStartWith, const QString &aFilters,
                const QString &aCaption) :
                mParent (aParent), mTarget (aTarget),
                mStartWith (aStartWith), mFilters (aFilters),
                mCaption (aCaption) {}

        virtual void run()
        {
            QString result;

            QString workDir;
            QString initSel;
            QFileInfo fi (mStartWith);

            if (fi.isDir())
                workDir = mStartWith;
            else
            {
                workDir = fi.absolutePath();
                initSel = fi.fileName();
            }

            workDir = QDir::toNativeSeparators (workDir);
            if (!workDir.endsWith ("\\"))
                workDir += "\\";

            QString title = mCaption.isNull() ? tr ("Select a file") : mCaption;

            QWidget *topParent = mParent ? mParent->window() : vboxGlobal().mainWindow();
            QString winFilters = winFilter (mFilters);
            AssertCompile (sizeof (TCHAR) == sizeof (QChar));
            TCHAR buf [1024];
            if (initSel.length() > 0 && initSel.length() < sizeof (buf))
                memcpy (buf, initSel.isNull() ? 0 : initSel.utf16(),
                        (initSel.length() + 1) * sizeof (TCHAR));
            else
                buf [0] = 0;

            OPENFILENAME ofn;
            memset (&ofn, 0, sizeof (OPENFILENAME));

            ofn.lStructSize = sizeof (OPENFILENAME);
            ofn.hwndOwner = topParent ? topParent->winId() : 0;
            ofn.lpstrFilter = (TCHAR *) winFilters.isNull() ? 0 : winFilters.utf16();
            ofn.lpstrFile = buf;
            ofn.nMaxFile = sizeof (buf) - 1;
            ofn.lpstrInitialDir = (TCHAR *) workDir.isNull() ? 0 : workDir.utf16();
            ofn.lpstrTitle = (TCHAR *) title.isNull() ? 0 : title.utf16();
            ofn.Flags = (OFN_NOCHANGEDIR | OFN_HIDEREADONLY |
                          OFN_EXPLORER | OFN_ENABLEHOOK |
                          OFN_FILEMUSTEXIST | OFN_PATHMUSTEXIST);
            ofn.lpfnHook = OFNHookProc;

            if (GetOpenFileName (&ofn))
            {
                result = QString::fromUtf16 ((ushort *) ofn.lpstrFile);
            }

            // qt_win_eatMouseMove();
            MSG msg = {0, 0, 0, 0, 0, 0, 0};
            while (PeekMessage (&msg, 0, WM_MOUSEMOVE, WM_MOUSEMOVE, PM_REMOVE));
            if (msg.message == WM_MOUSEMOVE)
                PostMessage (msg.hwnd, msg.message, 0, msg.lParam);

            result = result.isEmpty() ? result : QFileInfo (result).absoluteFilePath();

            QApplication::postEvent (mTarget, new GetOpenFileNameEvent (result));
        }

    private:

        QWidget *mParent;
        QObject *mTarget;
        QString mStartWith;
        QString mFilters;
        QString mCaption;
    };

    if (aSelectedFilter)
        *aSelectedFilter = QString::null;

    /* Local event loop to run while waiting for the result from another
     * thread */
    QEventLoop loop;

    QString startWith = QDir::toNativeSeparators (aStartWith);
    LoopObject loopObject ((QEvent::Type) GetOpenFileNameEvent::TypeId, loop);

    if (aParent)
        aParent->setWindowModality (Qt::WindowModal);

    Thread openDirThread (aParent, &loopObject, startWith, aFilters, aCaption);
    openDirThread.start();
    loop.exec();
    openDirThread.wait();

    if (aParent)
        aParent->setWindowModality (Qt::NonModal);

    return QStringList() << loopObject.result();

#elif defined (Q_WS_X11) && (QT_VERSION < 0x040400)

    /* Here is workaround for Qt4.3 bug with QFileDialog which crushes when
     * gets initial path as hidden directory if no hidden files are shown.
     * See http://trolltech.com/developer/task-tracker/index_html?method=entry&id=193483
     * for details */
    QFileDialog dlg (aParent);
    dlg.setWindowTitle (aCaption);
    dlg.setDirectory (aStartWith);
    dlg.setFilter (aFilters);
    if (aSingleFile)
        dlg.setFileMode (QFileDialog::ExistingFile);
    else
        dlg.setFileMode (QFileDialog::ExistingFiles);
    if (aSelectedFilter)
        dlg.selectFilter (*aSelectedFilter);
    dlg.setResolveSymlinks (aResolveSymlinks);
    QAction *hidden = dlg.findChild <QAction*> ("qt_show_hidden_action");
    if (hidden)
    {
        hidden->trigger();
        hidden->setVisible (false);
    }
    return dlg.exec() == QDialog::Accepted ? dlg.selectedFiles() : QStringList() << QString::null;

#elif defined (Q_WS_MAC) && (QT_VERSION >= 0x040600)

    /* After 4.5 exec ignores the Qt::Sheet flag. See "New Ways of Using
     * Dialogs" in http://doc.trolltech.com/qq/QtQuarterly30.pdf why. Because
     * we are lazy, we recreate the old behavior. Unfortunately there is a bug
     * in Qt 4.5.x which result in showing the native & the Qt dialog at the
     * same time. */
    QFileDialog dlg (aParent, Qt::Sheet);
    dlg.setWindowTitle (aCaption);
    dlg.setDirectory (aStartWith);
    dlg.setNameFilter (aFilters);
    if (aSingleFile)
        dlg.setFileMode (QFileDialog::ExistingFile);
    else
        dlg.setFileMode (QFileDialog::ExistingFiles);
    if (aSelectedFilter)
        dlg.selectFilter (*aSelectedFilter);
    dlg.setResolveSymlinks (aResolveSymlinks);

    QEventLoop eventLoop;
    QObject::connect(&dlg, SIGNAL(finished(int)),
                     &eventLoop, SLOT(quit()));
    /* Use the new open call. */
    dlg.open();
    eventLoop.exec();

    return dlg.result() == QDialog::Accepted ? dlg.selectedFiles() : QStringList() << QString::null;

#else

    QFileDialog::Options o;
    if (!aResolveSymlinks)
        o |= QFileDialog::DontResolveSymlinks;
# if defined (Q_WS_X11)
    /** @todo see http://bugs.kde.org/show_bug.cgi?id=210904, make it conditional
     *        when this bug is fixed (xtracker 5167)
     *        Apparently not necessary anymore (xtracker 5748)! */
//    if (vboxGlobal().isKWinManaged())
//      o |= QFileDialog::DontUseNativeDialog;
# endif

    if (aSingleFile)
        return QStringList() << QFileDialog::getOpenFileName (aParent, aCaption, aStartWith,
                                                              aFilters, aSelectedFilter, o);
    else
        return QFileDialog::getOpenFileNames (aParent, aCaption, aStartWith,
                                              aFilters, aSelectedFilter, o);
#endif
}

/**
 *  Search for the first directory that exists starting from the passed one
 *  and going up through its parents.  In case if none of the directories
 *  exist (except the root one), the function returns QString::null.
 */
/* static */
QString QIFileDialog::getFirstExistingDir (const QString &aStartDir)
{
    QString result = QString::null;
    QDir dir (aStartDir);
    while (!dir.exists() && !dir.isRoot())
    {
        QFileInfo dirInfo (dir.absolutePath());
        if (dir == QDir(dirInfo.absolutePath()))
            break;
        dir = dirInfo.absolutePath();
    }
    if (dir.exists() && !dir.isRoot())
        result = dir.absolutePath();
    return result;
}

#if defined Q_WS_WIN
#include "QIFileDialog.moc"
#endif

