/////////////////////////////////////////////////////////////////////////////
// Name:        src/common/cshelp.cpp
// Purpose:     Context sensitive help class implementation
// Author:      Julian Smart, Vadim Zeitlin
// Modified by:
// Created:     08/09/2000
// RCS-ID:      $Id$
// Copyright:   (c) 2000 Julian Smart, Vadim Zeitlin
// Licence:     wxWindows licence
/////////////////////////////////////////////////////////////////////////////

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

#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
    #pragma implementation "cshelp.h"
#endif

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

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

#ifdef __BORLANDC__
    #pragma hdrstop
#endif

#if wxUSE_HELP

#ifndef WX_PRECOMP
#endif

#include "wx/tipwin.h"
#include "wx/app.h"
#include "wx/module.h"
#include "wx/cshelp.h"

// ----------------------------------------------------------------------------
// wxContextHelpEvtHandler private class
// ----------------------------------------------------------------------------

// This class exists in order to eat events until the left mouse button is
// pressed
class wxContextHelpEvtHandler: public wxEvtHandler
{
public:
    wxContextHelpEvtHandler(wxContextHelp* contextHelp)
    {
        m_contextHelp = contextHelp;
    }

    virtual bool ProcessEvent(wxEvent& event);

//// Data
    wxContextHelp* m_contextHelp;

    DECLARE_NO_COPY_CLASS(wxContextHelpEvtHandler)
};

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

// ----------------------------------------------------------------------------
// wxContextHelp
// ----------------------------------------------------------------------------

/*
 * Invokes context-sensitive help
 */


IMPLEMENT_DYNAMIC_CLASS(wxContextHelp, wxObject)

wxContextHelp::wxContextHelp(wxWindow* win, bool beginHelp)
{
    m_inHelp = false;

    if (beginHelp)
        BeginContextHelp(win);
}

wxContextHelp::~wxContextHelp()
{
    if (m_inHelp)
        EndContextHelp();
}

// Not currently needed, but on some systems capture may not work as
// expected so we'll leave it here for now.
#ifdef __WXMOTIF__
static void wxPushOrPopEventHandlers(wxContextHelp* help, wxWindow* win, bool push)
{
    if (push)
        win->PushEventHandler(new wxContextHelpEvtHandler(help));
    else
        win->PopEventHandler(true);

    wxWindowList::compatibility_iterator node = win->GetChildren().GetFirst();
    while (node)
    {
        wxWindow* child = node->GetData();
        wxPushOrPopEventHandlers(help, child, push);

        node = node->GetNext();
    }
}
#endif

// Begin 'context help mode'
bool wxContextHelp::BeginContextHelp(wxWindow* win)
{
    if (!win)
        win = wxTheApp->GetTopWindow();
    if (!win)
        return false;

    wxCursor cursor(wxCURSOR_QUESTION_ARROW);
    wxCursor oldCursor = win->GetCursor();
    win->SetCursor(cursor);

#ifdef __WXMSW__
    //    wxSetCursor(cursor);
#endif

    m_status = false;

#ifdef __WXMOTIF__
    wxPushOrPopEventHandlers(this, win, true);
#else
    win->PushEventHandler(new wxContextHelpEvtHandler(this));
#endif

    win->CaptureMouse();

    EventLoop();

    win->ReleaseMouse();

#ifdef __WXMOTIF__
    wxPushOrPopEventHandlers(this, win, false);
#else
    win->PopEventHandler(true);
#endif

    win->SetCursor(oldCursor);

    if (m_status)
    {
        wxPoint pt;
        wxWindow* winAtPtr = wxFindWindowAtPointer(pt);

#if 0
        if (winAtPtr)
        {
            printf("Picked %s (%d)\n", winAtPtr->GetName().c_str(),
                   winAtPtr->GetId());
        }
#endif

        if (winAtPtr)
            DispatchEvent(winAtPtr, pt);
    }

    return true;
}

bool wxContextHelp::EndContextHelp()
{
    m_inHelp = false;

    return true;
}

bool wxContextHelp::EventLoop()
{
    m_inHelp = true;

    while ( m_inHelp )
    {
        if (wxTheApp->Pending())
        {
            wxTheApp->Dispatch();
        }
        else
        {
            wxTheApp->ProcessIdle();
        }
    }

    return true;
}

bool wxContextHelpEvtHandler::ProcessEvent(wxEvent& event)
{
    if (event.GetEventType() == wxEVT_LEFT_DOWN)
    {
        m_contextHelp->SetStatus(true);
        m_contextHelp->EndContextHelp();
        return true;
    }

    if ((event.GetEventType() == wxEVT_CHAR) ||
        (event.GetEventType() == wxEVT_KEY_DOWN) ||
        (event.GetEventType() == wxEVT_ACTIVATE) ||
        (event.GetEventType() == wxEVT_MOUSE_CAPTURE_CHANGED))
    {
        // May have already been set to true by a left-click
        //m_contextHelp->SetStatus(false);
        m_contextHelp->EndContextHelp();
        return true;
    }

    if ((event.GetEventType() == wxEVT_PAINT) ||
        (event.GetEventType() == wxEVT_ERASE_BACKGROUND))
    {
        event.Skip();
        return false;
    }

    return true;
}

// Dispatch the help event to the relevant window
bool wxContextHelp::DispatchEvent(wxWindow* win, const wxPoint& pt)
{
    wxWindow* subjectOfHelp = win;
    bool eventProcessed = false;
    while (subjectOfHelp && !eventProcessed)
    {
        wxHelpEvent helpEvent(wxEVT_HELP, subjectOfHelp->GetId(), pt) ;
        helpEvent.SetEventObject(subjectOfHelp);

        eventProcessed = win->GetEventHandler()->ProcessEvent(helpEvent);

        // Go up the window hierarchy until the event is handled (or not).
        // I.e. keep submitting ancestor windows until one is recognised
        // by the app code that processes the ids and displays help.
        subjectOfHelp = subjectOfHelp->GetParent();
    }
    return eventProcessed;
}

// ----------------------------------------------------------------------------
// wxContextHelpButton
// ----------------------------------------------------------------------------

/*
 * wxContextHelpButton
 * You can add this to your dialogs (especially on non-Windows platforms)
 * to put the application into context help mode.
 */

static const char * csquery_xpm[] = {
"12 11 2 1",
"  c None",
". c #000000",
"            ",
"    ....    ",
"   ..  ..   ",
"   ..  ..   ",
"      ..    ",
"     ..     ",
"     ..     ",
"            ",
"     ..     ",
"     ..     ",
"            "};

IMPLEMENT_CLASS(wxContextHelpButton, wxBitmapButton)

BEGIN_EVENT_TABLE(wxContextHelpButton, wxBitmapButton)
    EVT_BUTTON(wxID_CONTEXT_HELP, wxContextHelpButton::OnContextHelp)
END_EVENT_TABLE()

wxContextHelpButton::wxContextHelpButton(wxWindow* parent,
                                         wxWindowID id,
                                         const wxPoint& pos,
                                         const wxSize& size,
                                         long style)
#if defined(__WXPM__)
                   : wxBitmapButton(parent, id, wxBitmap(wxCSQUERY_BITMAP
                                                         ,wxBITMAP_TYPE_RESOURCE
                                                        ),
                                    pos, size, style)
#else
                   : wxBitmapButton(parent, id, wxBitmap(csquery_xpm),
                                    pos, size, style)
#endif
{
}

void wxContextHelpButton::OnContextHelp(wxCommandEvent& WXUNUSED(event))
{
    wxContextHelp contextHelp(GetParent());
}

// ----------------------------------------------------------------------------
// wxHelpProvider
// ----------------------------------------------------------------------------

wxHelpProvider *wxHelpProvider::ms_helpProvider = (wxHelpProvider *)NULL;

// trivial implementation of some methods which we don't want to make pure
// virtual for convenience

void wxHelpProvider::AddHelp(wxWindowBase * WXUNUSED(window),
                             const wxString& WXUNUSED(text))
{
}

void wxHelpProvider::AddHelp(wxWindowID WXUNUSED(id),
                             const wxString& WXUNUSED(text))
{
}

// removes the association
void wxHelpProvider::RemoveHelp(wxWindowBase* WXUNUSED(window))
{
}

wxHelpProvider::~wxHelpProvider()
{
}

// ----------------------------------------------------------------------------
// wxSimpleHelpProvider
// ----------------------------------------------------------------------------

wxString wxSimpleHelpProvider::GetHelp(const wxWindowBase *window)
{
    wxLongToStringHashMap::iterator it = m_hashWindows.find((long)window);

    if ( it == m_hashWindows.end() )
    {
        it = m_hashIds.find(window->GetId());
        if ( it == m_hashIds.end() )
            return wxEmptyString;
    }

    return it->second;
}

void wxSimpleHelpProvider::AddHelp(wxWindowBase *window, const wxString& text)
{
    m_hashWindows.erase((long)window);
    m_hashWindows[(long)window] = text;
}

void wxSimpleHelpProvider::AddHelp(wxWindowID id, const wxString& text)
{
    wxLongToStringHashMap::key_type key = (wxLongToStringHashMap::key_type)id;
    m_hashIds.erase(key);
    m_hashIds[key] = text;
}

// removes the association
void wxSimpleHelpProvider::RemoveHelp(wxWindowBase* window)
{
    m_hashWindows.erase((long)window);
}

bool wxSimpleHelpProvider::ShowHelp(wxWindowBase *window)
{
#if wxUSE_TIPWINDOW
    static wxTipWindow* s_tipWindow = NULL;

    if (s_tipWindow)
    {
        // Prevent s_tipWindow being nulled in OnIdle,
        // thereby removing the chance for the window to be closed by ShowHelp
        s_tipWindow->SetTipWindowPtr(NULL);
        s_tipWindow->Close();
    }
    s_tipWindow = NULL;

    wxString text = GetHelp(window);
    if ( !text.empty() )
    {
        s_tipWindow = new wxTipWindow((wxWindow *)window, text, 100, & s_tipWindow);

        return true;
    }
#else
    wxUnusedVar(window);
#endif // wxUSE_TIPWINDOW

    return false;
}

// ----------------------------------------------------------------------------
// wxHelpControllerHelpProvider
// ----------------------------------------------------------------------------

wxHelpControllerHelpProvider::wxHelpControllerHelpProvider(wxHelpControllerBase* hc)
{
    m_helpController = hc;
}

bool wxHelpControllerHelpProvider::ShowHelp(wxWindowBase *window)
{
    wxString text = GetHelp(window);
    if ( !text.empty() )
    {
        if (m_helpController)
        {
            if (text.IsNumber())
                return m_helpController->DisplayContextPopup(wxAtoi(text));

            // If the help controller is capable of popping up the text...
            else if (m_helpController->DisplayTextPopup(text, wxGetMousePosition()))
            {
                return true;
            }
            else
            // ...else use the default method.
                return wxSimpleHelpProvider::ShowHelp(window);
        }
        else
            return wxSimpleHelpProvider::ShowHelp(window);

    }

    return false;
}

// Convenience function for turning context id into wxString
wxString wxContextId(int id)
{
    return wxString::Format(_T("%d"), id);
}

// ----------------------------------------------------------------------------
// wxHelpProviderModule: module responsible for cleaning up help provider.
// ----------------------------------------------------------------------------

class wxHelpProviderModule : public wxModule
{
public:
    bool OnInit();
    void OnExit();

private:
    DECLARE_DYNAMIC_CLASS(wxHelpProviderModule)
};

IMPLEMENT_DYNAMIC_CLASS(wxHelpProviderModule, wxModule)

bool wxHelpProviderModule::OnInit()
{
    // Probably we don't want to do anything by default,
    // since it could pull in extra code
    // wxHelpProvider::Set(new wxSimpleHelpProvider);

    return true;
}

void wxHelpProviderModule::OnExit()
{
    if (wxHelpProvider::Get())
    {
        delete wxHelpProvider::Get();
        wxHelpProvider::Set(NULL);
    }
}

#endif // wxUSE_HELP