/ExtLibs/wxWidgets/src/common/docview.cpp

/////////////////////////////////////////////////////////////////////////////
// Name:        src/common/docview.cpp
// Purpose:     Document/view classes
// Author:      Julian Smart
// Modified by: Vadim Zeitlin
// Created:     01/02/97
// RCS-ID:      $Id$
// Copyright:   (c) Julian Smart
// Licence:     wxWindows licence
/////////////////////////////////////////////////////////////////////////////

// ============================================================================
// declarations
// ============================================================================

// ----------------------------------------------------------------------------
// headers
// ----------------------------------------------------------------------------

// For compilers that support precompilation, includes "wx.h".
#include "wx/wxprec.h"

#ifdef __BORLANDC__
    #pragma hdrstop
#endif

#if wxUSE_DOC_VIEW_ARCHITECTURE

#include "wx/docview.h"

#ifndef WX_PRECOMP
    #include "wx/list.h"
    #include "wx/string.h"
    #include "wx/utils.h"
    #include "wx/app.h"
    #include "wx/dc.h"
    #include "wx/dialog.h"
    #include "wx/menu.h"
    #include "wx/filedlg.h"
    #include "wx/intl.h"
    #include "wx/log.h"
    #include "wx/msgdlg.h"
    #include "wx/mdi.h"
    #include "wx/choicdlg.h"
#endif

#if wxUSE_PRINTING_ARCHITECTURE
    #include "wx/prntbase.h"
    #include "wx/printdlg.h"
#endif

#include "wx/confbase.h"
#include "wx/filename.h"
#include "wx/file.h"
#include "wx/ffile.h"
#include "wx/cmdproc.h"
#include "wx/tokenzr.h"
#include "wx/filename.h"
#include "wx/stdpaths.h"
#include "wx/vector.h"
#include "wx/scopedarray.h"
#include "wx/scopedptr.h"
#include "wx/except.h"

#if wxUSE_STD_IOSTREAM
    #include "wx/ioswrap.h"
    #include "wx/beforestd.h"
    #if wxUSE_IOSTREAMH
        #include <fstream.h>
    #else
        #include <fstream>
    #endif
    #include "wx/afterstd.h"
#else
    #include "wx/wfstream.h"
#endif

typedef wxVector<wxDocTemplate *> wxDocTemplates;

// ----------------------------------------------------------------------------
// wxWidgets macros
// ----------------------------------------------------------------------------

IMPLEMENT_ABSTRACT_CLASS(wxDocument, wxEvtHandler)
IMPLEMENT_ABSTRACT_CLASS(wxView, wxEvtHandler)
IMPLEMENT_ABSTRACT_CLASS(wxDocTemplate, wxObject)
IMPLEMENT_DYNAMIC_CLASS(wxDocManager, wxEvtHandler)
IMPLEMENT_CLASS(wxDocChildFrame, wxFrame)
IMPLEMENT_CLASS(wxDocParentFrame, wxFrame)

#if wxUSE_PRINTING_ARCHITECTURE
    IMPLEMENT_DYNAMIC_CLASS(wxDocPrintout, wxPrintout)
#endif

// ============================================================================
// implementation
// ============================================================================

// ----------------------------------------------------------------------------
// private helpers
// ----------------------------------------------------------------------------

namespace
{

wxString FindExtension(const wxString& path)
{
    wxString ext;
    wxFileName::SplitPath(path, NULL, NULL, &ext);

    // VZ: extensions are considered not case sensitive - is this really a good
    //     idea?
    return ext.MakeLower();
}

} // anonymous namespace

// ----------------------------------------------------------------------------
// Definition of wxDocument
// ----------------------------------------------------------------------------

wxDocument::wxDocument(wxDocument *parent)
{
    m_documentModified = false;
    m_documentTemplate = NULL;

    m_documentParent = parent;
    if ( parent )
        parent->m_childDocuments.push_back(this);

    m_commandProcessor = NULL;
    m_savedYet = false;
}

bool wxDocument::DeleteContents()
{
    return true;
}

wxDocument::~wxDocument()
{
    delete m_commandProcessor;

    if (GetDocumentManager())
        GetDocumentManager()->RemoveDocument(this);

    if ( m_documentParent )
        m_documentParent->m_childDocuments.remove(this);

    // Not safe to do here, since it'll invoke virtual view functions
    // expecting to see valid derived objects: and by the time we get here,
    // we've called destructors higher up.
    //DeleteAllViews();
}

bool wxDocument::Close()
{
    if ( !OnSaveModified() )
        return false;

    // When the parent document closes, its children must be closed as well as
    // they can't exist without the parent.

    // As usual, first check if all children can be closed.
    DocsList::const_iterator it = m_childDocuments.begin();
    for ( DocsList::const_iterator end = m_childDocuments.end(); it != end; ++it )
    {
        if ( !(*it)->OnSaveModified() )
        {
            // Leave the parent document opened if a child can't close.
            return false;
        }
    }

    // Now that they all did, do close them: as m_childDocuments is modified as
    // we iterate over it, don't use the usual for-style iteration here.
    while ( !m_childDocuments.empty() )
    {
        wxDocument * const childDoc = m_childDocuments.front();

        // This will call OnSaveModified() once again but it shouldn't do
        // anything as the document was just saved or marked as not needing to
        // be saved by the call to OnSaveModified() that returned true above.
        if ( !childDoc->Close() )
        {
            wxFAIL_MSG( "Closing the child document unexpectedly failed "
                        "after its OnSaveModified() returned true" );
        }

        // Delete the child document by deleting all its views.
        childDoc->DeleteAllViews();
    }


    return OnCloseDocument();
}

bool wxDocument::OnCloseDocument()
{
    // Tell all views that we're about to close
    NotifyClosing();
    DeleteContents();
    Modify(false);
    return true;
}

// Note that this implicitly deletes the document when the last view is
// deleted.
bool wxDocument::DeleteAllViews()
{
    wxDocManager* manager = GetDocumentManager();

    // first check if all views agree to be closed
    const wxList::iterator end = m_documentViews.end();
    for ( wxList::iterator i = m_documentViews.begin(); i != end; ++i )
    {
        wxView *view = (wxView *)*i;
        if ( !view->Close() )
            return false;
    }

    // all views agreed to close, now do close them
    if ( m_documentViews.empty() )
    {
        // normally the document would be implicitly deleted when the last view
        // is, but if don't have any views, do it here instead
        if ( manager && manager->GetDocuments().Member(this) )
            delete this;
    }
    else // have views
    {
        // as we delete elements we iterate over, don't use the usual "from
        // begin to end" loop
        for ( ;; )
        {
            wxView *view = (wxView *)*m_documentViews.begin();

            bool isLastOne = m_documentViews.size() == 1;

            // this always deletes the node implicitly and if this is the last
            // view also deletes this object itself (also implicitly, great),
            // so we can't test for m_documentViews.empty() after calling this!
            delete view;

            if ( isLastOne )
                break;
        }
    }

    return true;
}

wxView *wxDocument::GetFirstView() const
{
    if ( m_documentViews.empty() )
        return NULL;

    return static_cast<wxView *>(m_documentViews.GetFirst()->GetData());
}

void wxDocument::Modify(bool mod)
{
    if (mod != m_documentModified)
    {
        m_documentModified = mod;

        // Allow views to append asterix to the title
        wxView* view = GetFirstView();
        if (view) view->OnChangeFilename();
    }
}

wxDocManager *wxDocument::GetDocumentManager() const
{
    // For child documents we use the same document manager as the parent, even
    // though we don't have our own template (as children are not opened/saved
    // directly).
    if ( m_documentParent )
        return m_documentParent->GetDocumentManager();

    return m_documentTemplate ? m_documentTemplate->GetDocumentManager() : NULL;
}

bool wxDocument::OnNewDocument()
{
    // notice that there is no need to neither reset nor even check the
    // modified flag here as the document itself is a new object (this is only
    // called from CreateDocument()) and so it shouldn't be saved anyhow even
    // if it is modified -- this could happen if the user code creates
    // documents pre-filled with some user-entered (and which hence must not be
    // lost) information

    SetDocumentSaved(false);

    const wxString name = GetDocumentManager()->MakeNewDocumentName();
    SetTitle(name);
    SetFilename(name, true);

    return true;
}

bool wxDocument::Save()
{
    if ( AlreadySaved() )
        return true;

    if ( m_documentFile.empty() || !m_savedYet )
        return SaveAs();

    return OnSaveDocument(m_documentFile);
}

bool wxDocument::SaveAs()
{
    wxDocTemplate *docTemplate = GetDocumentTemplate();
    if (!docTemplate)
        return false;

#ifdef wxHAS_MULTIPLE_FILEDLG_FILTERS
    wxString filter = docTemplate->GetDescription() + wxT(" (") +
        docTemplate->GetFileFilter() + wxT(")|") +
        docTemplate->GetFileFilter();

    // Now see if there are some other template with identical view and document
    // classes, whose filters may also be used.
    if (docTemplate->GetViewClassInfo() && docTemplate->GetDocClassInfo())
    {
        wxList::compatibility_iterator
            node = docTemplate->GetDocumentManager()->GetTemplates().GetFirst();
        while (node)
        {
            wxDocTemplate *t = (wxDocTemplate*) node->GetData();

            if (t->IsVisible() && t != docTemplate &&
                t->GetViewClassInfo() == docTemplate->GetViewClassInfo() &&
                t->GetDocClassInfo() == docTemplate->GetDocClassInfo())
            {
                // add a '|' to separate this filter from the previous one
                if ( !filter.empty() )
                    filter << wxT('|');

                filter << t->GetDescription()
                       << wxT(" (") << t->GetFileFilter() << wxT(") |")
                       << t->GetFileFilter();
            }

            node = node->GetNext();
        }
    }
#else
    wxString filter = docTemplate->GetFileFilter() ;
#endif

    wxString defaultDir = docTemplate->GetDirectory();
    if ( defaultDir.empty() )
    {
        defaultDir = wxPathOnly(GetFilename());
        if ( defaultDir.empty() )
            defaultDir = GetDocumentManager()->GetLastDirectory();
    }

    wxString fileName = wxFileSelector(_("Save As"),
            defaultDir,
            wxFileNameFromPath(GetFilename()),
            docTemplate->GetDefaultExtension(),
            filter,
            wxFD_SAVE | wxFD_OVERWRITE_PROMPT,
            GetDocumentWindow());

    if (fileName.empty())
        return false; // cancelled by user

    // Files that were not saved correctly are not added to the FileHistory.
    if (!OnSaveDocument(fileName))
        return false;

    SetTitle(wxFileNameFromPath(fileName));
    SetFilename(fileName, true);    // will call OnChangeFileName automatically

    // A file that doesn't use the default extension of its document template
    // cannot be opened via the FileHistory, so we do not add it.
    if (docTemplate->FileMatchesTemplate(fileName))
    {
        GetDocumentManager()->AddFileToHistory(fileName);
    }
    //else: the user will probably not be able to open the file again, so we
    //      could warn about the wrong file-extension here

    return true;
}

bool wxDocument::OnSaveDocument(const wxString& file)
{
    if ( !file )
        return false;

    if ( !DoSaveDocument(file) )
        return false;

    Modify(false);
    SetFilename(file);
    SetDocumentSaved(true);
#if defined( __WXOSX_MAC__ ) && wxOSX_USE_CARBON
    wxFileName fn(file) ;
    fn.MacSetDefaultTypeAndCreator() ;
#endif
    return true;
}

bool wxDocument::OnOpenDocument(const wxString& file)
{
    // notice that there is no need to check the modified flag here for the
    // reasons explained in OnNewDocument()

    if ( !DoOpenDocument(file) )
        return false;

    SetFilename(file, true);

    // stretching the logic a little this does make sense because the document
    // had been saved into the file we just loaded it from, it just could have
    // happened during a previous program execution, it's just that the name of
    // this method is a bit unfortunate, it should probably have been called
    // HasAssociatedFileName()
    SetDocumentSaved(true);

    UpdateAllViews();

    return true;
}

#if wxUSE_STD_IOSTREAM
wxSTD istream& wxDocument::LoadObject(wxSTD istream& stream)
#else
wxInputStream& wxDocument::LoadObject(wxInputStream& stream)
#endif
{
    return stream;
}

#if wxUSE_STD_IOSTREAM
wxSTD ostream& wxDocument::SaveObject(wxSTD ostream& stream)
#else
wxOutputStream& wxDocument::SaveObject(wxOutputStream& stream)
#endif
{
    return stream;
}

bool wxDocument::Revert()
{
    if ( wxMessageBox
         (
            _("Discard changes and reload the last saved version?"),
            wxTheApp->GetAppDisplayName(),
            wxYES_NO | wxCANCEL | wxICON_QUESTION,
            GetDocumentWindow()
          ) != wxYES )
        return false;

    if ( !DoOpenDocument(GetFilename()) )
        return false;

    Modify(false);
    UpdateAllViews();

    return true;
}


// Get title, or filename if no title, else unnamed
#if WXWIN_COMPATIBILITY_2_8
bool wxDocument::GetPrintableName(wxString& buf) const
{
    // this function cannot only be overridden by the user code but also
    // called by it so we need to ensure that we return the same thing as
    // GetUserReadableName() but we can't call it because this would result in
    // an infinite recursion, hence we use the helper DoGetUserReadableName()
    buf = DoGetUserReadableName();

    return true;
}
#endif // WXWIN_COMPATIBILITY_2_8

wxString wxDocument::GetUserReadableName() const
{
#if WXWIN_COMPATIBILITY_2_8
    // we need to call the old virtual function to ensure that the overridden
    // version of it is still called
    wxString name;
    if ( GetPrintableName(name) )
        return name;
#endif // WXWIN_COMPATIBILITY_2_8

    return DoGetUserReadableName();
}

wxString wxDocument::DoGetUserReadableName() const
{
    if ( !m_documentTitle.empty() )
        return m_documentTitle;

    if ( !m_documentFile.empty() )
        return wxFileNameFromPath(m_documentFile);

    return _("unnamed");
}

wxWindow *wxDocument::GetDocumentWindow() const
{
    wxView * const view = GetFirstView();

    return view ? view->GetFrame() : wxTheApp->GetTopWindow();
}

wxCommandProcessor *wxDocument::OnCreateCommandProcessor()
{
    return new wxCommandProcessor;
}

// true if safe to close
bool wxDocument::OnSaveModified()
{
    if ( IsModified() )
    {
        switch ( wxMessageBox
                 (
                    wxString::Format
                    (
                     _("Do you want to save changes to %s?"),
                     GetUserReadableName()
                    ),
                    wxTheApp->GetAppDisplayName(),
                    wxYES_NO | wxCANCEL | wxICON_QUESTION | wxCENTRE
                 ) )
        {
            case wxNO:
                Modify(false);
                break;

            case wxYES:
                return Save();

            case wxCANCEL:
                return false;
        }
    }

    return true;
}

bool wxDocument::Draw(wxDC& WXUNUSED(context))
{
    return true;
}

bool wxDocument::AddView(wxView *view)
{
    if ( !m_documentViews.Member(view) )
    {
        m_documentViews.Append(view);
        OnChangedViewList();
    }
    return true;
}

bool wxDocument::RemoveView(wxView *view)
{
    (void)m_documentViews.DeleteObject(view);
    OnChangedViewList();
    return true;
}

bool wxDocument::OnCreate(const wxString& WXUNUSED(path), long flags)
{
    return GetDocumentTemplate()->CreateView(this, flags) != NULL;
}

// Called after a view is added or removed.
// The default implementation deletes the document if
// there are no more views.
void wxDocument::OnChangedViewList()
{
    if ( m_documentViews.empty() && OnSaveModified() )
        delete this;
}

void wxDocument::UpdateAllViews(wxView *sender, wxObject *hint)
{
    wxList::compatibility_iterator node = m_documentViews.GetFirst();
    while (node)
    {
        wxView *view = (wxView *)node->GetData();
        if (view != sender)
            view->OnUpdate(sender, hint);
        node = node->GetNext();
    }
}

void wxDocument::NotifyClosing()
{
    wxList::compatibility_iterator node = m_documentViews.GetFirst();
    while (node)
    {
        wxView *view = (wxView *)node->GetData();
        view->OnClosingDocument();
        node = node->GetNext();
    }
}

void wxDocument::SetFilename(const wxString& filename, bool notifyViews)
{
    m_documentFile = filename;
    OnChangeFilename(notifyViews);
}

void wxDocument::OnChangeFilename(bool notifyViews)
{
    if ( notifyViews )
    {
        // Notify the views that the filename has changed
        wxList::compatibility_iterator node = m_documentViews.GetFirst();
        while (node)
        {
            wxView *view = (wxView *)node->GetData();
            view->OnChangeFilename();
            node = node->GetNext();
        }
    }
}

bool wxDocument::DoSaveDocument(const wxString& file)
{
#if wxUSE_STD_IOSTREAM
    wxSTD ofstream store(file.mb_str(), wxSTD ios::binary);
    if ( !store )
#else
    wxFileOutputStream store(file);
    if ( store.GetLastError() != wxSTREAM_NO_ERROR )
#endif
    {
        wxLogError(_("File \"%s\" could not be opened for writing."), file);
        return false;
    }

    if (!SaveObject(store))
    {
        wxLogError(_("Failed to save document to the file \"%s\"."), file);
        return false;
    }

    return true;
}

bool wxDocument::DoOpenDocument(const wxString& file)
{
#if wxUSE_STD_IOSTREAM
    wxSTD ifstream store(file.mb_str(), wxSTD ios::binary);
    if ( !store )
#else
    wxFileInputStream store(file);
    if (store.GetLastError() != wxSTREAM_NO_ERROR || !store.IsOk())
#endif
    {
        wxLogError(_("File \"%s\" could not be opened for reading."), file);
        return false;
    }

#if wxUSE_STD_IOSTREAM
    LoadObject(store);
    if ( !store )
#else
    int res = LoadObject(store).GetLastError();
    if ( res != wxSTREAM_NO_ERROR && res != wxSTREAM_EOF )
#endif
    {
        wxLogError(_("Failed to read document from the file \"%s\"."), file);
        return false;
    }

    return true;
}


// ----------------------------------------------------------------------------
// Document view
// ----------------------------------------------------------------------------

wxView::wxView()
{
    m_viewDocument = NULL;

    m_viewFrame = NULL;

    m_docChildFrame = NULL;
}

wxView::~wxView()
{
    if (m_viewDocument && GetDocumentManager())
        GetDocumentManager()->ActivateView(this, false);

    // reset our frame view first, before removing it from the document as
    // SetView(NULL) is a simple call while RemoveView() may result in user
    // code being executed and this user code can, for example, show a message
    // box which would result in an activation event for m_docChildFrame and so
    // could reactivate the view being destroyed -- unless we reset it first
    if ( m_docChildFrame && m_docChildFrame->GetView() == this )
    {
        // prevent it from doing anything with us
        m_docChildFrame->SetView(NULL);

        // it doesn't make sense to leave the frame alive if its associated
        // view doesn't exist any more so unconditionally close it as well
        //
        // notice that we only get here if m_docChildFrame is non-NULL in the
        // first place and it will be always NULL if we're deleted because our
        // frame was closed, so this only catches the case of directly deleting
        // the view, as it happens if its creation fails in wxDocTemplate::
        // CreateView() for example
        m_docChildFrame->GetWindow()->Destroy();
    }

    if ( m_viewDocument )
        m_viewDocument->RemoveView(this);
}

void wxView::SetDocChildFrame(wxDocChildFrameAnyBase *docChildFrame)
{
    SetFrame(docChildFrame ? docChildFrame->GetWindow() : NULL);
    m_docChildFrame = docChildFrame;
}

bool wxView::TryBefore(wxEvent& event)
{
    wxDocument * const doc = GetDocument();
    return doc && doc->ProcessEventLocally(event);
}

void wxView::OnActivateView(bool WXUNUSED(activate),
                            wxView *WXUNUSED(activeView),
                            wxView *WXUNUSED(deactiveView))
{
}

void wxView::OnPrint(wxDC *dc, wxObject *WXUNUSED(info))
{
    OnDraw(dc);
}

void wxView::OnUpdate(wxView *WXUNUSED(sender), wxObject *WXUNUSED(hint))
{
}

void wxView::OnChangeFilename()
{
    // GetFrame can return wxWindow rather than wxTopLevelWindow due to
    // generic MDI implementation so use SetLabel rather than SetTitle.
    // It should cause SetTitle() for top level windows.
    wxWindow *win = GetFrame();
    if (!win) return;

    wxDocument *doc = GetDocument();
    if (!doc) return;

    wxString label = doc->GetUserReadableName();
    if (doc->IsModified())
    {
       label += "*";
    }
    win->SetLabel(label);
}

void wxView::SetDocument(wxDocument *doc)
{
    m_viewDocument = doc;
    if (doc)
        doc->AddView(this);
}

bool wxView::Close(bool deleteWindow)
{
    return OnClose(deleteWindow);
}

void wxView::Activate(bool activate)
{
    if (GetDocument() && GetDocumentManager())
    {
        OnActivateView(activate, this, GetDocumentManager()->GetCurrentView());
        GetDocumentManager()->ActivateView(this, activate);
    }
}

bool wxView::OnClose(bool WXUNUSED(deleteWindow))
{
    return GetDocument() ? GetDocument()->Close() : true;
}

#if wxUSE_PRINTING_ARCHITECTURE
wxPrintout *wxView::OnCreatePrintout()
{
    return new wxDocPrintout(this);
}
#endif // wxUSE_PRINTING_ARCHITECTURE

// ----------------------------------------------------------------------------
// wxDocTemplate
// ----------------------------------------------------------------------------

wxDocTemplate::wxDocTemplate(wxDocManager *manager,
                             const wxString& descr,
                             const wxString& filter,
                             const wxString& dir,
                             const wxString& ext,
                             const wxString& docTypeName,
                             const wxString& viewTypeName,
                             wxClassInfo *docClassInfo,
                             wxClassInfo *viewClassInfo,
                             long flags)
{
    m_documentManager = manager;
    m_description = descr;
    m_directory = dir;
    m_defaultExt = ext;
    m_fileFilter = filter;
    m_flags = flags;
    m_docTypeName = docTypeName;
    m_viewTypeName = viewTypeName;
    m_documentManager->AssociateTemplate(this);

    m_docClassInfo = docClassInfo;
    m_viewClassInfo = viewClassInfo;
}

wxDocTemplate::~wxDocTemplate()
{
    m_documentManager->DisassociateTemplate(this);
}

// Tries to dynamically construct an object of the right class.
wxDocument *wxDocTemplate::CreateDocument(const wxString& path, long flags)
{
    // InitDocument() is supposed to delete the document object if its
    // initialization fails so don't use wxScopedPtr<> here: this is fragile
    // but unavoidable because the default implementation uses CreateView()
    // which may -- or not -- create a wxView and if it does create it and its
    // initialization fails then the view destructor will delete the document
    // (via RemoveView()) and as we can't distinguish between the two cases we
    // just have to assume that it always deletes it in case of failure
    wxDocument * const doc = DoCreateDocument();

    return doc && InitDocument(doc, path, flags) ? doc : NULL;
}

bool
wxDocTemplate::InitDocument(wxDocument* doc, const wxString& path, long flags)
{
    doc->SetFilename(path);
    doc->SetDocumentTemplate(this);
    GetDocumentManager()->AddDocument(doc);
    doc->SetCommandProcessor(doc->OnCreateCommandProcessor());

    if (doc->OnCreate(path, flags))
        return true;

    if (GetDocumentManager()->GetDocuments().Member(doc))
        doc->DeleteAllViews();
    return false;
}

wxView *wxDocTemplate::CreateView(wxDocument *doc, long flags)
{
    wxScopedPtr<wxView> view(DoCreateView());
    if ( !view )
        return NULL;

    view->SetDocument(doc);
    if ( !view->OnCreate(doc, flags) )
        return NULL;

    return view.release();
}

// The default (very primitive) format detection: check is the extension is
// that of the template
bool wxDocTemplate::FileMatchesTemplate(const wxString& path)
{
    wxStringTokenizer parser (GetFileFilter(), wxT(";"));
    wxString anything = wxT ("*");
    while (parser.HasMoreTokens())
    {
        wxString filter = parser.GetNextToken();
        wxString filterExt = FindExtension (filter);
        if ( filter.IsSameAs (anything)    ||
             filterExt.IsSameAs (anything) ||
             filterExt.IsSameAs (FindExtension (path)) )
            return true;
    }
    return GetDefaultExtension().IsSameAs(FindExtension(path));
}

wxDocument *wxDocTemplate::DoCreateDocument()
{
    if (!m_docClassInfo)
        return NULL;

    return static_cast<wxDocument *>(m_docClassInfo->CreateObject());
}

wxView *wxDocTemplate::DoCreateView()
{
    if (!m_viewClassInfo)
        return NULL;

    return static_cast<wxView *>(m_viewClassInfo->CreateObject());
}

// ----------------------------------------------------------------------------
// wxDocManager
// ----------------------------------------------------------------------------

BEGIN_EVENT_TABLE(wxDocManager, wxEvtHandler)
    EVT_MENU(wxID_OPEN, wxDocManager::OnFileOpen)
    EVT_MENU(wxID_CLOSE, wxDocManager::OnFileClose)
    EVT_MENU(wxID_CLOSE_ALL, wxDocManager::OnFileCloseAll)
    EVT_MENU(wxID_REVERT, wxDocManager::OnFileRevert)
    EVT_MENU(wxID_NEW, wxDocManager::OnFileNew)
    EVT_MENU(wxID_SAVE, wxDocManager::OnFileSave)
    EVT_MENU(wxID_SAVEAS, wxDocManager::OnFileSaveAs)
    EVT_MENU(wxID_UNDO, wxDocManager::OnUndo)
    EVT_MENU(wxID_REDO, wxDocManager::OnRedo)

    // We don't know in advance how many items can there be in the MRU files
    // list so set up OnMRUFile() as a handler for all menu events and do the
    // check for the id of the menu item clicked inside it.
    EVT_MENU(wxID_ANY, wxDocManager::OnMRUFile)

    EVT_UPDATE_UI(wxID_OPEN, wxDocManager::OnUpdateFileOpen)
    EVT_UPDATE_UI(wxID_CLOSE, wxDocManager::OnUpdateDisableIfNoDoc)
    EVT_UPDATE_UI(wxID_CLOSE_ALL, wxDocManager::OnUpdateDisableIfNoDoc)
    EVT_UPDATE_UI(wxID_REVERT, wxDocManager::OnUpdateFileRevert)
    EVT_UPDATE_UI(wxID_NEW, wxDocManager::OnUpdateFileNew)
    EVT_UPDATE_UI(wxID_SAVE, wxDocManager::OnUpdateFileSave)
    EVT_UPDATE_UI(wxID_SAVEAS, wxDocManager::OnUpdateFileSaveAs)
    EVT_UPDATE_UI(wxID_UNDO, wxDocManager::OnUpdateUndo)
    EVT_UPDATE_UI(wxID_REDO, wxDocManager::OnUpdateRedo)

#if wxUSE_PRINTING_ARCHITECTURE
    EVT_MENU(wxID_PRINT, wxDocManager::OnPrint)
    EVT_MENU(wxID_PREVIEW, wxDocManager::OnPreview)
    EVT_MENU(wxID_PRINT_SETUP, wxDocManager::OnPageSetup)

    EVT_UPDATE_UI(wxID_PRINT, wxDocManager::OnUpdateDisableIfNoDoc)
    EVT_UPDATE_UI(wxID_PREVIEW, wxDocManager::OnUpdateDisableIfNoDoc)
    // NB: we keep "Print setup" menu item always enabled as it can be used
    //     even without an active document
#endif // wxUSE_PRINTING_ARCHITECTURE
END_EVENT_TABLE()

wxDocManager* wxDocManager::sm_docManager = NULL;

wxDocManager::wxDocManager(long WXUNUSED(flags), bool initialize)
{
    sm_docManager = this;

    m_defaultDocumentNameCounter = 1;
    m_currentView = NULL;
    m_maxDocsOpen = INT_MAX;
    m_fileHistory = NULL;
    if ( initialize )
        Initialize();
}

wxDocManager::~wxDocManager()
{
    Clear();
    delete m_fileHistory;
    sm_docManager = NULL;
}

// closes the specified document
bool wxDocManager::CloseDocument(wxDocument* doc, bool force)
{
    if ( !doc->Close() && !force )
        return false;

    // Implicitly deletes the document when
    // the last view is deleted
    doc->DeleteAllViews();

    // Check we're really deleted
    if (m_docs.Member(doc))
        delete doc;

    return true;
}

bool wxDocManager::CloseDocuments(bool force)
{
    wxList::compatibility_iterator node = m_docs.GetFirst();
    while (node)
    {
        wxDocument *doc = (wxDocument *)node->GetData();
        wxList::compatibility_iterator next = node->GetNext();

        if (!CloseDocument(doc, force))
            return false;

        // This assumes that documents are not connected in
        // any way, i.e. deleting one document does NOT
        // delete another.
        node = next;
    }
    return true;
}

bool wxDocManager::Clear(bool force)
{
    if (!CloseDocuments(force))
        return false;

    m_currentView = NULL;

    wxList::compatibility_iterator node = m_templates.GetFirst();
    while (node)
    {
        wxDocTemplate *templ = (wxDocTemplate*) node->GetData();
        wxList::compatibility_iterator next = node->GetNext();
        delete templ;
        node = next;
    }
    return true;
}

bool wxDocManager::Initialize()
{
    m_fileHistory = OnCreateFileHistory();
    return true;
}

wxString wxDocManager::GetLastDirectory() const
{
    // if we haven't determined the last used directory yet, do it now
    if ( m_lastDirectory.empty() )
    {
        // we're going to modify m_lastDirectory in this const method, so do it
        // via non-const self pointer instead of const this one
        wxDocManager * const self = const_cast<wxDocManager *>(this);

        // first try to reuse the directory of the most recently opened file:
        // this ensures that if the user opens a file, closes the program and
        // runs it again the "Open file" dialog will open in the directory of
        // the last file he used
        if ( m_fileHistory && m_fileHistory->GetCount() )
        {
            const wxString lastOpened = m_fileHistory->GetHistoryFile(0);
            const wxFileName fn(lastOpened);
            if ( fn.DirExists() )
            {
                self->m_lastDirectory = fn.GetPath();
            }
            //else: should we try the next one?
        }
        //else: no history yet

        // if we don't have any files in the history (yet?), use the
        // system-dependent default location for the document files
        if ( m_lastDirectory.empty() )
        {
            self->m_lastDirectory = wxStandardPaths::Get().GetAppDocumentsDir();
        }
    }

    return m_lastDirectory;
}

wxFileHistory *wxDocManager::OnCreateFileHistory()
{
    return new wxFileHistory;
}

void wxDocManager::OnFileClose(wxCommandEvent& WXUNUSED(event))
{
    wxDocument *doc = GetCurrentDocument();
    if (doc)
        CloseDocument(doc);
}

void wxDocManager::OnFileCloseAll(wxCommandEvent& WXUNUSED(event))
{
    CloseDocuments(false);
}

void wxDocManager::OnFileNew(wxCommandEvent& WXUNUSED(event))
{
    CreateNewDocument();
}

void wxDocManager::OnFileOpen(wxCommandEvent& WXUNUSED(event))
{
    if ( !CreateDocument("") )
    {
        OnOpenFileFailure();
    }
}

void wxDocManager::OnFileRevert(wxCommandEvent& WXUNUSED(event))
{
    wxDocument *doc = GetCurrentDocument();
    if (!doc)
        return;
    doc->Revert();
}

void wxDocManager::OnFileSave(wxCommandEvent& WXUNUSED(event))
{
    wxDocument *doc = GetCurrentDocument();
    if (!doc)
        return;
    doc->Save();
}

void wxDocManager::OnFileSaveAs(wxCommandEvent& WXUNUSED(event))
{
    wxDocument *doc = GetCurrentDocument();
    if (!doc)
        return;
    doc->SaveAs();
}

void wxDocManager::OnMRUFile(wxCommandEvent& event)
{
    // Check if the id is in the range assigned to MRU list entries.
    const int id = event.GetId();
    if ( id >= wxID_FILE1 &&
            id < wxID_FILE1 + static_cast<int>(m_fileHistory->GetCount()) )
    {
        DoOpenMRUFile(id - wxID_FILE1);
    }
    else
    {
        event.Skip();
    }
}

void wxDocManager::DoOpenMRUFile(unsigned n)
{
    wxString filename(GetHistoryFile(n));
    if ( filename.empty() )
        return;

    wxString errMsg; // must contain exactly one "%s" if non-empty
    if ( wxFile::Exists(filename) )
    {
        // try to open it
        if ( CreateDocument(filename, wxDOC_SILENT) )
            return;

        errMsg = _("The file '%s' couldn't be opened.");
    }
    else // file doesn't exist
    {
        errMsg = _("The file '%s' doesn't exist and couldn't be opened.");
    }


    wxASSERT_MSG( !errMsg.empty(), "should have an error message" );

    // remove the file which we can't open from the MRU list
    RemoveFileFromHistory(n);

    // and tell the user about it
    wxLogError(errMsg + '\n' +
               _("It has been removed from the most recently used files list."),
               filename);
}

#if wxUSE_PRINTING_ARCHITECTURE

void wxDocManager::OnPrint(wxCommandEvent& WXUNUSED(event))
{
    wxView *view = GetActiveView();
    if (!view)
        return;

    wxPrintout *printout = view->OnCreatePrintout();
    if (printout)
    {
        wxPrintDialogData printDialogData(m_pageSetupDialogData.GetPrintData());
        wxPrinter printer(&printDialogData);
        printer.Print(view->GetFrame(), printout, true);

        delete printout;
    }
}

void wxDocManager::OnPageSetup(wxCommandEvent& WXUNUSED(event))
{
    wxPageSetupDialog dlg(wxTheApp->GetTopWindow(), &m_pageSetupDialogData);
    if ( dlg.ShowModal() == wxID_OK )
    {
        m_pageSetupDialogData = dlg.GetPageSetupData();
    }
}

wxPreviewFrame* wxDocManager::CreatePreviewFrame(wxPrintPreviewBase* preview,
                                                 wxWindow *parent,
                                                 const wxString& title)
{
    return new wxPreviewFrame(preview, parent, title);
}

void wxDocManager::OnPreview(wxCommandEvent& WXUNUSED(event))
{
    wxBusyCursor busy;
    wxView *view = GetActiveView();
    if (!view)
        return;

    wxPrintout *printout = view->OnCreatePrintout();
    if (printout)
    {
        wxPrintDialogData printDialogData(m_pageSetupDialogData.GetPrintData());

        // Pass two printout objects: for preview, and possible printing.
        wxPrintPreviewBase *
            preview = new wxPrintPreview(printout,
                                         view->OnCreatePrintout(),
                                         &printDialogData);
        if ( !preview->IsOk() )
        {
            delete preview;
            wxLogError(_("Print preview creation failed."));
            return;
        }

        wxPreviewFrame* frame = CreatePreviewFrame(preview,
                                                   wxTheApp->GetTopWindow(),
                                                   _("Print Preview"));
        wxCHECK_RET( frame, "should create a print preview frame" );

        frame->Centre(wxBOTH);
        frame->Initialize();
        frame->Show(true);
    }
}
#endif // wxUSE_PRINTING_ARCHITECTURE

void wxDocManager::OnUndo(wxCommandEvent& event)
{
    wxCommandProcessor * const cmdproc = GetCurrentCommandProcessor();
    if ( !cmdproc )
    {
        event.Skip();
        return;
    }

    cmdproc->Undo();
}

void wxDocManager::OnRedo(wxCommandEvent& event)
{
    wxCommandProcessor * const cmdproc = GetCurrentCommandProcessor();
    if ( !cmdproc )
    {
        event.Skip();
        return;
    }

    cmdproc->Redo();
}

// Handlers for UI update commands

void wxDocManager::OnUpdateFileOpen(wxUpdateUIEvent& event)
{
    // CreateDocument() (which is called from OnFileOpen) may succeed
    // only when there is at least a template:
    event.Enable( GetTemplates().GetCount()>0 );
}

void wxDocManager::OnUpdateDisableIfNoDoc(wxUpdateUIEvent& event)
{
    event.Enable( GetCurrentDocument() != NULL );
}

void wxDocManager::OnUpdateFileRevert(wxUpdateUIEvent& event)
{
    wxDocument* doc = GetCurrentDocument();
    event.Enable(doc && doc->IsModified() && doc->GetDocumentSaved());
}

void wxDocManager::OnUpdateFileNew(wxUpdateUIEvent& event)
{
    // CreateDocument() (which is called from OnFileNew) may succeed
    // only when there is at least a template:
    event.Enable( GetTemplates().GetCount()>0 );
}

void wxDocManager::OnUpdateFileSave(wxUpdateUIEvent& event)
{
    wxDocument * const doc = GetCurrentDocument();
    event.Enable( doc && !doc->IsChildDocument() && !doc->AlreadySaved() );
}

void wxDocManager::OnUpdateFileSaveAs(wxUpdateUIEvent& event)
{
    wxDocument * const doc = GetCurrentDocument();
    event.Enable( doc && !doc->IsChildDocument() );
}

void wxDocManager::OnUpdateUndo(wxUpdateUIEvent& event)
{
    wxCommandProcessor * const cmdproc = GetCurrentCommandProcessor();
    if ( !cmdproc )
    {
        event.Enable(false);
        return;
    }

    event.Enable(cmdproc->CanUndo());
    cmdproc->SetMenuStrings();
}

void wxDocManager::OnUpdateRedo(wxUpdateUIEvent& event)
{
    wxCommandProcessor * const cmdproc = GetCurrentCommandProcessor();
    if ( !cmdproc )
    {
        event.Enable(false);
        return;
    }

    event.Enable(cmdproc->CanRedo());
    cmdproc->SetMenuStrings();
}

wxView *wxDocManager::GetActiveView() const
{
    wxView *view = GetCurrentView();

    if ( !view && !m_docs.empty() )
    {
        // if we have exactly one document, consider its view to be the current
        // one
        //
        // VZ: I'm not exactly sure why is this needed but this is how this
        //     code used to behave before the bug #9518 was fixed and it seems
        //     safer to preserve the old logic
        wxList::compatibility_iterator node = m_docs.GetFirst();
        if ( !node->GetNext() )
        {
            wxDocument *doc = static_cast<wxDocument *>(node->GetData());
            view = doc->GetFirstView();
        }
        //else: we have more than one document
    }

    return view;
}

bool wxDocManager::TryBefore(wxEvent& event)
{
    wxView * const view = GetActiveView();
    return view && view->ProcessEventLocally(event);
}

namespace
{

// helper function: return only the visible templates
wxDocTemplates GetVisibleTemplates(const wxList& allTemplates)
{
    // select only the visible templates
    const size_t totalNumTemplates = allTemplates.GetCount();
    wxDocTemplates templates;
    if ( totalNumTemplates )
    {
        templates.reserve(totalNumTemplates);

        for ( wxList::const_iterator i = allTemplates.begin(),
                                   end = allTemplates.end();
              i != end;
              ++i )
        {
            wxDocTemplate * const temp = (wxDocTemplate *)*i;
            if ( temp->IsVisible() )
                templates.push_back(temp);
        }
    }

    return templates;
}

} // anonymous namespace

void wxDocManager::ActivateDocument(wxDocument *doc)
{
    wxView * const view = doc->GetFirstView();
    if ( !view )
        return;

    view->Activate(true);
    if ( wxWindow *win = view->GetFrame() )
        win->SetFocus();
}

wxDocument *wxDocManager::CreateDocument(const wxString& pathOrig, long flags)
{
    // this ought to be const but SelectDocumentType/Path() are not
    // const-correct and can't be changed as, being virtual, this risks
    // breaking user code overriding them
    wxDocTemplates templates(GetVisibleTemplates(m_templates));
    const size_t numTemplates = templates.size();
    if ( !numTemplates )
    {
        // no templates can be used, can't create document
        return NULL;
    }


    // normally user should select the template to use but wxDOC_SILENT flag we
    // choose one ourselves
    wxString path = pathOrig;   // may be modified below
    wxDocTemplate *temp;
    if ( flags & wxDOC_SILENT )
    {
        wxASSERT_MSG( !path.empty(),
                      "using empty path with wxDOC_SILENT doesn't make sense" );

        temp = FindTemplateForPath(path);
        if ( !temp )
        {
            wxLogWarning(_("The format of file '%s' couldn't be determined."),
                         path);
        }
    }
    else // not silent, ask the user
    {
        // for the new file we need just the template, for an existing one we
        // need the template and the path, unless it's already specified
        if ( (flags & wxDOC_NEW) || !path.empty() )
            temp = SelectDocumentType(&templates[0], numTemplates);
        else
            temp = SelectDocumentPath(&templates[0], numTemplates, path, flags);
    }

    if ( !temp )
        return NULL;

    // check whether the document with this path is already opened
    if ( !path.empty() )
    {
        const wxFileName fn(path);
        for ( wxList::const_iterator i = m_docs.begin(); i != m_docs.end(); ++i )
        {
            wxDocument * const doc = (wxDocument*)*i;

            if ( fn == doc->GetFilename() )
            {
                // file already open, just activate it and return
                ActivateDocument(doc);
                return doc;
            }
        }
    }


    // no, we need to create a new document


    // if we've reached the max number of docs, close the first one.
    if ( (int)GetDocuments().GetCount() >= m_maxDocsOpen )
    {
        if ( !CloseDocument((wxDocument *)GetDocuments().GetFirst()->GetData()) )
        {
            // can't open the new document if closing the old one failed
            return NULL;
        }
    }


    // do create and initialize the new document finally
    wxDocument * const docNew = temp->CreateDocument(path, flags);
    if ( !docNew )
        return NULL;

    docNew->SetDocumentName(temp->GetDocumentName());
    docNew->SetDocumentTemplate(temp);

    wxTRY
    {
        // call the appropriate function depending on whether we're creating a
        // new file or opening an existing one
        if ( !(flags & wxDOC_NEW ? docNew->OnNewDocument()
                                 : docNew->OnOpenDocument(path)) )
        {
            docNew->DeleteAllViews();
            return NULL;
        }
    }
    wxCATCH_ALL( docNew->DeleteAllViews(); throw; )

    // add the successfully opened file to MRU, but only if we're going to be
    // able to reopen it successfully later which requires the template for
    // this document to be retrievable from the file extension
    if ( !(flags & wxDOC_NEW) && temp->FileMatchesTemplate(path) )
        AddFileToHistory(path);

    // at least under Mac (where views are top level windows) it seems to be
    // necessary to manually activate the new document to bring it to the
    // forefront -- and it shouldn't hurt doing this under the other platforms
    ActivateDocument(docNew);

    return docNew;
}

wxView *wxDocManager::CreateView(wxDocument *doc, long flags)
{
    wxDocTemplates templates(GetVisibleTemplates(m_templates));
    const size_t numTemplates = templates.size();

    if ( numTemplates == 0 )
        return NULL;

    wxDocTemplate * const
    temp = numTemplates == 1 ? templates[0]
                             : SelectViewType(&templates[0], numTemplates);

    if ( !temp )
        return NULL;

    wxView *view = temp->CreateView(doc, flags);
    if ( view )
        view->SetViewName(temp->GetViewName());
    return view;
}

// Not yet implemented
void
wxDocManager::DeleteTemplate(wxDocTemplate *WXUNUSED(temp), long WXUNUSED(flags))
{
}

// Not yet implemented
bool wxDocManager::FlushDoc(wxDocument *WXUNUSED(doc))
{
    return false;
}

wxDocument *wxDocManager::GetCurrentDocument() const
{
    wxView * const view = GetActiveView();
    return view ? view->GetDocument() : NULL;
}

wxCommandProcessor *wxDocManager::GetCurrentCommandProcessor() const
{
    wxDocument * const doc = GetCurrentDocument();
    return doc ? doc->GetCommandProcessor() : NULL;
}

// Make a default name for a new document
#if WXWIN_COMPATIBILITY_2_8
bool wxDocManager::MakeDefaultName(wxString& WXUNUSED(name))
{
    // we consider that this function can only be overridden by the user code,
    // not called by it as it only makes sense to call it internally, so we
    // don't bother to return anything from here
    return false;
}
#endif // WXWIN_COMPATIBILITY_2_8

wxString wxDocManager::MakeNewDocumentName()
{
    wxString name;

#if WXWIN_COMPATIBILITY_2_8
    if ( !MakeDefaultName(name) )
#endif // WXWIN_COMPATIBILITY_2_8
    {
        name.Printf(_("unnamed%d"), m_defaultDocumentNameCounter);
        m_defaultDocumentNameCounter++;
    }

    return name;
}

// Make a frame title (override this to do something different)
// If docName is empty, a document is not currently active.
wxString wxDocManager::MakeFrameTitle(wxDocument* doc)
{
    wxString appName = wxTheApp->GetAppDisplayName();
    wxString title;
    if (!doc)
        title = appName;
    else
    {
        wxString docName = doc->GetUserReadableName();
        title = docName + wxString(_(" - ")) + appName;
    }
    return title;
}


// Not yet implemented
wxDocTemplate *wxDocManager::MatchTemplate(const wxString& WXUNUSED(path))
{
    return NULL;
}

// File history management
void wxDocManager::AddFileToHistory(const wxString& file)
{
    if (m_fileHistory)
        m_fileHistory->AddFileToHistory(file);
}

void wxDocManager::RemoveFileFromHistory(size_t i)
{
    if (m_fileHistory)
        m_fileHistory->RemoveFileFromHistory(i);
}

wxString wxDocManager::GetHistoryFile(size_t i) const
{
    wxString histFile;

    if (m_fileHistory)
        histFile = m_fileHistory->GetHistoryFile(i);

    return histFile;
}

void wxDocManager::FileHistoryUseMenu(wxMenu *menu)
{
    if (m_fileHistory)
        m_fileHistory->UseMenu(menu);
}

void wxDocManager::FileHistoryRemoveMenu(wxMenu *menu)
{
    if (m_fileHistory)
        m_fileHistory->RemoveMenu(menu);
}

#if wxUSE_CONFIG
void wxDocManager::FileHistoryLoad(const wxConfigBase& config)
{
    if (m_fileHistory)
        m_fileHistory->Load(config);
}

void wxDocManager::FileHistorySave(wxConfigBase& config)
{
    if (m_fileHistory)
        m_fileHistory->Save(config);
}
#endif

void wxDocManager::FileHistoryAddFilesToMenu(wxMenu* menu)
{
    if (m_fileHistory)
        m_fileHistory->AddFilesToMenu(menu);
}

void wxDocManager::FileHistoryAddFilesToMenu()
{
    if (m_fileHistory)
        m_fileHistory->AddFilesToMenu();
}

size_t wxDocManager::GetHistoryFilesCount() const
{
    return m_fileHistory ? m_fileHistory->GetCount() : 0;
}


// Find out the document template via matching in the document file format
// against that of the template
wxDocTemplate *wxDocManager::FindTemplateForPath(const wxString& path)
{
    wxDocTemplate *theTemplate = NULL;

    // Find the template which this extension corresponds to
    for (size_t i = 0; i < m_templates.GetCount(); i++)
    {
        wxDocTemplate *temp = (wxDocTemplate *)m_templates.Item(i)->GetData();
        if ( temp->FileMatchesTemplate(path) )
        {
            theTemplate = temp;
            break;
        }
    }
    return theTemplate;
}

// Prompts user to open a file, using file specs in templates.
// Must extend the file selector dialog or implement own; OR
// match the extension to the template extension.

wxDocTemplate *wxDocManager::SelectDocumentPath(wxDocTemplate **templates,
                                                int noTemplates,
                                                wxString& path,
                                                long WXUNUSED(flags),
                                                bool WXUNUSED(save))
{
#ifdef wxHAS_MULTIPLE_FILEDLG_FILTERS
    wxString descrBuf;

    for (int i = 0; i < noTemplates; i++)
    {
        if (templates[i]->IsVisible())
        {
            // add a '|' to separate this filter from the previous one
            if ( !descrBuf.empty() )
                descrBuf << wxT('|');

            descrBuf << templates[i]->GetDescription()
                << wxT(" (") << templates[i]->GetFileFilter() << wxT(") |")
                << templates[i]->GetFileFilter();
        }
    }
#else
    wxString descrBuf = wxT("*.*");
    wxUnusedVar(noTemplates);
#endif

    int FilterIndex = -1;

    wxString pathTmp = wxFileSelectorEx(_("Open File"),
                                        GetLastDirectory(),
                                        wxEmptyString,
                                        &FilterIndex,
                                        descrBuf,
                                        wxFD_OPEN | wxFD_FILE_MUST_EXIST);

    wxDocTemplate *theTemplate = NULL;
    if (!pathTmp.empty())
    {
        if (!wxFileExists(pathTmp))
        {
            wxString msgTitle;
            if (!wxTheApp->GetAppDisplayName().empty())
                msgTitle = wxTheApp->GetAppDisplayName();
            else
                msgTitle = wxString(_("File error"));

            wxMessageBox(_("Sorry, could not open this file."),
                         msgTitle,
                         wxOK | wxICON_EXCLAMATION | wxCENTRE);

            path = wxEmptyString;
            return NULL;
        }

        SetLastDirectory(wxPathOnly(pathTmp));

        path = pathTmp;

        // first choose the template using the extension, if this fails (i.e.
        // wxFileSelectorEx() didn't fill it), then use the path
        if ( FilterIndex != -1 )
            theTemplate = templates[FilterIndex];
        if ( !theTemplate )
            theTemplate = FindTemplateForPath(path);
        if ( !theTemplate )
        {
            // Since we do not add files with non-default extensions to the
            // file history this can only happen if the application changes the
            // allowed templates in runtime.
            wxMessageBox(_("Sorry, the format for this file is unknown."),
                         _("Open File"),
                         wxOK | wxICON_EXCLAMATION | wxCENTRE);
        }
    }
    else
    {
        path.clear();
    }