/////////////////////////////////////////////////////////////////////////////
// Name:        src/common/event.cpp
// Purpose:     Event classes
// Author:      Julian Smart
// Created:     01/02/97
// Copyright:   (c) Julian Smart
// Licence:     wxWindows licence
/////////////////////////////////////////////////////////////////////////////

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

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

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


#include "wx/event.h"
#include "wx/eventfilter.h"
#include "wx/evtloop.h"

#ifndef WX_PRECOMP
    #include "wx/list.h"
    #include "wx/log.h"
    #include "wx/app.h"
    #include "wx/utils.h"
    #include "wx/stopwatch.h"
    #include "wx/module.h"

    #if wxUSE_GUI
        #include "wx/window.h"
        #include "wx/control.h"
        #include "wx/dc.h"
        #include "wx/spinbutt.h"
        #include "wx/textentry.h"
        #include "wx/validate.h"
    #endif // wxUSE_GUI
#endif

#include "wx/thread.h"

#if wxUSE_BASE
    #include <memory>
#endif // wxUSE_BASE

#if wxUSE_GUI
    #include "wx/private/rescale.h"
#endif

// ----------------------------------------------------------------------------
// wxWin macros
// ----------------------------------------------------------------------------

#if wxUSE_BASE
    wxIMPLEMENT_DYNAMIC_CLASS(wxEvtHandler, wxObject);
    wxIMPLEMENT_ABSTRACT_CLASS(wxEvent, wxObject);
    wxIMPLEMENT_DYNAMIC_CLASS(wxIdleEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxThreadEvent, wxEvent);
#endif // wxUSE_BASE

#if wxUSE_GUI
    wxIMPLEMENT_DYNAMIC_CLASS(wxCommandEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxNotifyEvent, wxCommandEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxScrollEvent, wxCommandEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxScrollWinEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxMouseEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxKeyEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxSizeEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxPaintEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxNcPaintEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxEraseEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxMoveEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxFocusEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxChildFocusEvent, wxCommandEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxCloseEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxShowEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxMaximizeEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxIconizeEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxFullScreenEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxMenuEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxJoystickEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxDropFilesEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxActivateEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxInitDialogEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxSetCursorEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxSysColourChangedEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxDisplayChangedEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxDPIChangedEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxUpdateUIEvent, wxCommandEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxNavigationKeyEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxPaletteChangedEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxQueryNewPaletteEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxWindowCreateEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxWindowDestroyEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxHelpEvent, wxCommandEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxContextMenuEvent, wxCommandEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxMouseCaptureChangedEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxMouseCaptureLostEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxClipboardTextEvent, wxCommandEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxGestureEvent, wxEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxPanGestureEvent, wxGestureEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxZoomGestureEvent, wxGestureEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxRotateGestureEvent, wxGestureEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxTwoFingerTapEvent, wxGestureEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxLongPressEvent, wxGestureEvent);
    wxIMPLEMENT_DYNAMIC_CLASS(wxPressAndTapEvent, wxGestureEvent);
#endif // wxUSE_GUI

#if wxUSE_BASE

const wxEventTable *wxEvtHandler::GetEventTable() const
    { return &wxEvtHandler::sm_eventTable; }

const wxEventTable wxEvtHandler::sm_eventTable =
    { (const wxEventTable *)nullptr, &wxEvtHandler::sm_eventTableEntries[0] };

wxEventHashTable &wxEvtHandler::GetEventHashTable() const
    { return wxEvtHandler::sm_eventHashTable; }

wxEventHashTable wxEvtHandler::sm_eventHashTable(wxEvtHandler::sm_eventTable);

const wxEventTableEntry wxEvtHandler::sm_eventTableEntries[] =
    { wxDECLARE_EVENT_TABLE_TERMINATOR() };


// ----------------------------------------------------------------------------
// global variables
// ----------------------------------------------------------------------------

// common event types are defined here, other event types are defined by the
// components which use them

const wxEventType wxEVT_FIRST = 10000;
const wxEventType wxEVT_USER_FIRST = wxEVT_FIRST + 2000;
const wxEventType wxEVT_NULL = wxNewEventType();

wxDEFINE_EVENT( wxEVT_IDLE, wxIdleEvent );

// Thread and asynchronous call events
wxDEFINE_EVENT( wxEVT_THREAD, wxThreadEvent );
wxDEFINE_EVENT( wxEVT_ASYNC_METHOD_CALL, wxAsyncMethodCallEvent );

#endif // wxUSE_BASE

#if wxUSE_GUI

wxDEFINE_EVENT( wxEVT_BUTTON, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_CHECKBOX, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_CHOICE, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_LISTBOX, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_LISTBOX_DCLICK, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_CHECKLISTBOX, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_MENU, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_SLIDER, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_RADIOBOX, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_RADIOBUTTON, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_SCROLLBAR, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_VLBOX, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_COMBOBOX, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_TOOL_RCLICKED, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_TOOL_ENTER, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_TOOL_DROPDOWN, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_COMBOBOX_DROPDOWN, wxCommandEvent);
wxDEFINE_EVENT( wxEVT_COMBOBOX_CLOSEUP, wxCommandEvent);

// Mouse event types
wxDEFINE_EVENT( wxEVT_LEFT_DOWN, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_LEFT_UP, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_MIDDLE_DOWN, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_MIDDLE_UP, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_RIGHT_DOWN, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_RIGHT_UP, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_MOTION, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_ENTER_WINDOW, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_LEAVE_WINDOW, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_LEFT_DCLICK, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_MIDDLE_DCLICK, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_RIGHT_DCLICK, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_SET_FOCUS, wxFocusEvent );
wxDEFINE_EVENT( wxEVT_KILL_FOCUS, wxFocusEvent );
wxDEFINE_EVENT( wxEVT_CHILD_FOCUS, wxChildFocusEvent );
wxDEFINE_EVENT( wxEVT_MOUSEWHEEL, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_AUX1_DOWN, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_AUX1_UP, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_AUX1_DCLICK, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_AUX2_DOWN, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_AUX2_UP, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_AUX2_DCLICK, wxMouseEvent );
wxDEFINE_EVENT( wxEVT_MAGNIFY, wxMouseEvent );

// Character input event type
wxDEFINE_EVENT( wxEVT_CHAR, wxKeyEvent );
wxDEFINE_EVENT( wxEVT_AFTER_CHAR, wxKeyEvent );
wxDEFINE_EVENT( wxEVT_CHAR_HOOK, wxKeyEvent );
wxDEFINE_EVENT( wxEVT_NAVIGATION_KEY, wxNavigationKeyEvent );
wxDEFINE_EVENT( wxEVT_KEY_DOWN, wxKeyEvent );
wxDEFINE_EVENT( wxEVT_KEY_UP, wxKeyEvent );
#if wxUSE_HOTKEY
wxDEFINE_EVENT( wxEVT_HOTKEY, wxKeyEvent );
#endif

// Set cursor event
wxDEFINE_EVENT( wxEVT_SET_CURSOR, wxSetCursorEvent );

// wxScrollbar and wxSlider event identifiers
wxDEFINE_EVENT( wxEVT_SCROLL_TOP, wxScrollEvent );
wxDEFINE_EVENT( wxEVT_SCROLL_BOTTOM, wxScrollEvent );
wxDEFINE_EVENT( wxEVT_SCROLL_LINEUP, wxScrollEvent );
wxDEFINE_EVENT( wxEVT_SCROLL_LINEDOWN, wxScrollEvent );
wxDEFINE_EVENT( wxEVT_SCROLL_PAGEUP, wxScrollEvent );
wxDEFINE_EVENT( wxEVT_SCROLL_PAGEDOWN, wxScrollEvent );
wxDEFINE_EVENT( wxEVT_SCROLL_THUMBTRACK, wxScrollEvent );
wxDEFINE_EVENT( wxEVT_SCROLL_THUMBRELEASE, wxScrollEvent );
wxDEFINE_EVENT( wxEVT_SCROLL_CHANGED, wxScrollEvent );

// Due to a bug in older wx versions, wxSpinEvents were being sent with type of
// wxEVT_SCROLL_LINEUP, wxEVT_SCROLL_LINEDOWN and wxEVT_SCROLL_THUMBTRACK. But
// with the type-safe events in place, these event types are associated with
// wxScrollEvent. To allow handling of spin events, new event types have been
// defined in spinbutt.h/spinnbuttcmn.cpp. To maintain backward compatibility
// the spin event types are being initialized with the scroll event types.

#if wxUSE_SPINBTN

wxDEFINE_EVENT_ALIAS( wxEVT_SPIN_UP,   wxSpinEvent, wxEVT_SCROLL_LINEUP );
wxDEFINE_EVENT_ALIAS( wxEVT_SPIN_DOWN, wxSpinEvent, wxEVT_SCROLL_LINEDOWN );
wxDEFINE_EVENT_ALIAS( wxEVT_SPIN,      wxSpinEvent, wxEVT_SCROLL_THUMBTRACK );

#endif // wxUSE_SPINBTN

// Scroll events from wxWindow
wxDEFINE_EVENT( wxEVT_SCROLLWIN_TOP, wxScrollWinEvent );
wxDEFINE_EVENT( wxEVT_SCROLLWIN_BOTTOM, wxScrollWinEvent );
wxDEFINE_EVENT( wxEVT_SCROLLWIN_LINEUP, wxScrollWinEvent );
wxDEFINE_EVENT( wxEVT_SCROLLWIN_LINEDOWN, wxScrollWinEvent );
wxDEFINE_EVENT( wxEVT_SCROLLWIN_PAGEUP, wxScrollWinEvent );
wxDEFINE_EVENT( wxEVT_SCROLLWIN_PAGEDOWN, wxScrollWinEvent );
wxDEFINE_EVENT( wxEVT_SCROLLWIN_THUMBTRACK, wxScrollWinEvent );
wxDEFINE_EVENT( wxEVT_SCROLLWIN_THUMBRELEASE, wxScrollWinEvent );

// Gesture events
wxDEFINE_EVENT( wxEVT_GESTURE_PAN, wxPanGestureEvent );
wxDEFINE_EVENT( wxEVT_GESTURE_ZOOM, wxZoomGestureEvent );
wxDEFINE_EVENT( wxEVT_GESTURE_ROTATE, wxRotateGestureEvent );
wxDEFINE_EVENT( wxEVT_TWO_FINGER_TAP, wxTwoFingerTapEvent );
wxDEFINE_EVENT( wxEVT_LONG_PRESS, wxLongPressEvent );
wxDEFINE_EVENT( wxEVT_PRESS_AND_TAP, wxPressAndTapEvent );

// System events
wxDEFINE_EVENT( wxEVT_SIZE, wxSizeEvent );
wxDEFINE_EVENT( wxEVT_SIZING, wxSizeEvent );
wxDEFINE_EVENT( wxEVT_MOVE, wxMoveEvent );
wxDEFINE_EVENT( wxEVT_MOVING, wxMoveEvent );
wxDEFINE_EVENT( wxEVT_MOVE_START, wxMoveEvent );
wxDEFINE_EVENT( wxEVT_MOVE_END, wxMoveEvent );
wxDEFINE_EVENT( wxEVT_CLOSE_WINDOW, wxCloseEvent );
wxDEFINE_EVENT( wxEVT_END_SESSION, wxCloseEvent );
wxDEFINE_EVENT( wxEVT_QUERY_END_SESSION, wxCloseEvent );
wxDEFINE_EVENT( wxEVT_HIBERNATE, wxActivateEvent );
wxDEFINE_EVENT( wxEVT_ACTIVATE_APP, wxActivateEvent );
wxDEFINE_EVENT( wxEVT_ACTIVATE, wxActivateEvent );
wxDEFINE_EVENT( wxEVT_CREATE, wxWindowCreateEvent );
wxDEFINE_EVENT( wxEVT_DESTROY, wxWindowDestroyEvent );
wxDEFINE_EVENT( wxEVT_SHOW, wxShowEvent );
wxDEFINE_EVENT( wxEVT_ICONIZE, wxIconizeEvent );
wxDEFINE_EVENT( wxEVT_MAXIMIZE, wxMaximizeEvent );
wxDEFINE_EVENT( wxEVT_FULLSCREEN, wxFullScreenEvent );
wxDEFINE_EVENT( wxEVT_MOUSE_CAPTURE_CHANGED, wxMouseCaptureChangedEvent );
wxDEFINE_EVENT( wxEVT_MOUSE_CAPTURE_LOST, wxMouseCaptureLostEvent );
wxDEFINE_EVENT( wxEVT_PAINT, wxPaintEvent );
wxDEFINE_EVENT( wxEVT_ERASE_BACKGROUND, wxEraseEvent );
wxDEFINE_EVENT( wxEVT_NC_PAINT, wxNcPaintEvent );
wxDEFINE_EVENT( wxEVT_MENU_OPEN, wxMenuEvent );
wxDEFINE_EVENT( wxEVT_MENU_CLOSE, wxMenuEvent );
wxDEFINE_EVENT( wxEVT_MENU_HIGHLIGHT, wxMenuEvent );
wxDEFINE_EVENT( wxEVT_CONTEXT_MENU, wxContextMenuEvent );
wxDEFINE_EVENT( wxEVT_SYS_COLOUR_CHANGED, wxSysColourChangedEvent );
wxDEFINE_EVENT( wxEVT_DISPLAY_CHANGED, wxDisplayChangedEvent );
wxDEFINE_EVENT( wxEVT_DPI_CHANGED, wxDPIChangedEvent );
wxDEFINE_EVENT( wxEVT_QUERY_NEW_PALETTE, wxQueryNewPaletteEvent );
wxDEFINE_EVENT( wxEVT_PALETTE_CHANGED, wxPaletteChangedEvent );
wxDEFINE_EVENT( wxEVT_JOY_BUTTON_DOWN, wxJoystickEvent );
wxDEFINE_EVENT( wxEVT_JOY_BUTTON_UP, wxJoystickEvent );
wxDEFINE_EVENT( wxEVT_JOY_MOVE, wxJoystickEvent );
wxDEFINE_EVENT( wxEVT_JOY_ZMOVE, wxJoystickEvent );
wxDEFINE_EVENT( wxEVT_DROP_FILES, wxDropFilesEvent );
wxDEFINE_EVENT( wxEVT_INIT_DIALOG, wxInitDialogEvent );
wxDEFINE_EVENT( wxEVT_UPDATE_UI, wxUpdateUIEvent );

// Clipboard events
wxDEFINE_EVENT( wxEVT_TEXT_COPY, wxClipboardTextEvent );
wxDEFINE_EVENT( wxEVT_TEXT_CUT, wxClipboardTextEvent );
wxDEFINE_EVENT( wxEVT_TEXT_PASTE, wxClipboardTextEvent );

// Generic command events
// Note: a click is a higher-level event than button down/up
wxDEFINE_EVENT( wxEVT_COMMAND_LEFT_CLICK, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_COMMAND_LEFT_DCLICK, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_COMMAND_RIGHT_CLICK, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_COMMAND_RIGHT_DCLICK, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_COMMAND_SET_FOCUS, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_COMMAND_KILL_FOCUS, wxCommandEvent );
wxDEFINE_EVENT( wxEVT_COMMAND_ENTER, wxCommandEvent );

// Help events
wxDEFINE_EVENT( wxEVT_HELP, wxHelpEvent );
wxDEFINE_EVENT( wxEVT_DETAILED_HELP, wxHelpEvent );

#endif // wxUSE_GUI

#if wxUSE_BASE

wxIdleMode wxIdleEvent::sm_idleMode = wxIDLE_PROCESS_ALL;

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

// ----------------------------------------------------------------------------
// event initialization
// ----------------------------------------------------------------------------

int wxNewEventType()
{
    // MT-FIXME
    static int s_lastUsedEventType = wxEVT_FIRST;

    return s_lastUsedEventType++;
}
// ----------------------------------------------------------------------------
// wxEventFunctor
// ----------------------------------------------------------------------------

wxEventFunctor::~wxEventFunctor()
{
}

// ----------------------------------------------------------------------------
// wxEvent
// ----------------------------------------------------------------------------

/*
 * General wxWidgets events, covering all interesting things that might happen
 * (button clicking, resizing, setting text in widgets, etc.).
 *
 * For each completely new event type, derive a new event class.
 *
 */

wxEvent::wxEvent(int theId, wxEventType commandType)
    : m_eventType(commandType)
{
    m_eventObject = nullptr;
    m_timeStamp = 0;
    m_id = theId;
    m_skipped = false;
    m_callbackUserData = nullptr;
    m_handlerToProcessOnlyIn = nullptr;
    m_isCommandEvent = false;
    m_propagationLevel = wxEVENT_PROPAGATE_NONE;
    m_propagatedFrom = nullptr;
    m_wasProcessed = false;
    m_willBeProcessedAgain = false;
}

wxEvent::wxEvent(const wxEvent& src)
    : wxObject(src)
    , m_eventObject(src.m_eventObject)
    , m_eventType(src.m_eventType)
    , m_timeStamp(src.m_timeStamp)
    , m_id(src.m_id)
    , m_callbackUserData(src.m_callbackUserData)
    , m_handlerToProcessOnlyIn(nullptr)
    , m_propagationLevel(src.m_propagationLevel)
    , m_propagatedFrom(nullptr)
    , m_skipped(src.m_skipped)
    , m_isCommandEvent(src.m_isCommandEvent)
    , m_wasProcessed(false)
    , m_willBeProcessedAgain(false)
{
}

wxEvent& wxEvent::operator=(const wxEvent& src)
{
    wxObject::operator=(src);

    m_eventObject = src.m_eventObject;
    m_eventType = src.m_eventType;
    m_timeStamp = src.m_timeStamp;
    m_id = src.m_id;
    m_callbackUserData = src.m_callbackUserData;
    m_handlerToProcessOnlyIn = nullptr;
    m_propagationLevel = src.m_propagationLevel;
    m_propagatedFrom = nullptr;
    m_skipped = src.m_skipped;
    m_isCommandEvent = src.m_isCommandEvent;

    // don't change m_wasProcessed

    // While the original again could be passed to another handler, this one
    // isn't going to be processed anywhere else by default.
    m_willBeProcessedAgain = false;

    return *this;
}

#endif // wxUSE_BASE

#if wxUSE_GUI

// ----------------------------------------------------------------------------
// wxCommandEvent
// ----------------------------------------------------------------------------

wxString wxCommandEvent::GetString() const
{
    // This is part of the hack retrieving the event string from the control
    // itself only when/if it's really needed to avoid copying potentially huge
    // strings coming from multiline text controls.
    if (m_eventType == wxEVT_TEXT && m_eventObject)
    {
        // Only windows generate wxEVT_TEXT events, so this cast should really
        // succeed, but err on the side of caution just in case somebody
        // created a bogus event of this type.
        if ( wxWindow* const w = wxDynamicCast(m_eventObject, wxWindow) )
        {
            if ( const wxTextEntry* const entry = w->WXGetTextEntry() )
                return entry->GetValue();
        }
    }

    return m_cmdString;
}

// ----------------------------------------------------------------------------
// wxPaintEvent and wxNcPaintEvent
// ----------------------------------------------------------------------------

wxPaintEvent::wxPaintEvent(wxWindowBase* window)
    : wxEvent(window ? window->GetId() : 0, wxEVT_PAINT)
{
    SetEventObject(window);
}

wxNcPaintEvent::wxNcPaintEvent(wxWindowBase* window)
    : wxEvent(window ? window->GetId() : 0, wxEVT_NC_PAINT)
{
    SetEventObject(window);
}

// ----------------------------------------------------------------------------
// wxUpdateUIEvent
// ----------------------------------------------------------------------------

#if wxUSE_LONGLONG
wxLongLong wxUpdateUIEvent::sm_lastUpdate = 0;
#endif

long wxUpdateUIEvent::sm_updateInterval = 0;

wxUpdateUIMode wxUpdateUIEvent::sm_updateMode = wxUPDATE_UI_PROCESS_ALL;

// Can we update?
bool wxUpdateUIEvent::CanUpdate(wxWindowBase *win)
{
    // Don't update if we've switched global updating off
    // and this window doesn't support updates.
    if (win &&
       (GetMode() == wxUPDATE_UI_PROCESS_SPECIFIED &&
       ((win->GetExtraStyle() & wxWS_EX_PROCESS_UI_UPDATES) == 0)))
        return false;

    // Don't update children of the hidden windows: this is useless as any
    // change to their state won't be seen by the user anyhow. Notice that this
    // argument doesn't apply to the hidden windows (with visible parent)
    // themselves as they could be shown by their EVT_UPDATE_UI handler.
    if ( win->GetParent() && !win->GetParent()->IsShownOnScreen() )
        return false;

    if (sm_updateInterval == -1)
        return false;

    if (sm_updateInterval == 0)
        return true;

#if wxUSE_STOPWATCH && wxUSE_LONGLONG
    wxLongLong now = wxGetLocalTimeMillis();
    if (now > (sm_lastUpdate + sm_updateInterval))
    {
        return true;
    }

    return false;
#else
    // If we don't have wxStopWatch or wxLongLong, we
    // should err on the safe side and update now anyway.
    return true;
#endif
}

// Reset the update time to provide a delay until the next
// time we should update
void wxUpdateUIEvent::ResetUpdateTime()
{
#if wxUSE_STOPWATCH && wxUSE_LONGLONG
    if (sm_updateInterval > 0)
    {
        wxLongLong now = wxGetLocalTimeMillis();
        if (now > (sm_lastUpdate + sm_updateInterval))
        {
            sm_lastUpdate = now;
        }
    }
#endif
}

// ----------------------------------------------------------------------------
// wxScrollEvent
// ----------------------------------------------------------------------------

wxScrollEvent::wxScrollEvent(wxEventType commandType,
                             int id,
                             int pos,
                             int orient)
    : wxCommandEvent(commandType, id)
{
    m_extraLong = orient;
    m_commandInt = pos;
}

// ----------------------------------------------------------------------------
// wxScrollWinEvent
// ----------------------------------------------------------------------------

wxScrollWinEvent::wxScrollWinEvent(wxEventType commandType,
                                   int pos,
                                   int orient)
{
    m_eventType = commandType;
    m_extraLong = orient;
    m_commandInt = pos;
}

// ----------------------------------------------------------------------------
// wxMouseEvent
// ----------------------------------------------------------------------------

wxMouseEvent::wxMouseEvent(wxEventType commandType)
{
    m_eventType = commandType;

    m_x = 0;
    m_y = 0;

    m_leftDown = false;
    m_middleDown = false;
    m_rightDown = false;
    m_aux1Down = false;
    m_aux2Down = false;

    m_clickCount = -1;

    m_wheelAxis = wxMOUSE_WHEEL_VERTICAL;
    m_wheelRotation = 0;
    m_wheelDelta = 0;
    m_wheelInverted = false;
    m_linesPerAction = 0;
    m_columnsPerAction = 0;
    m_magnification = 0.0f;
}

void wxMouseEvent::Assign(const wxMouseEvent& event)
{
    wxEvent::operator=(event);
    wxMouseState::operator=(event);

    m_x = event.m_x;
    m_y = event.m_y;

    m_leftDown = event.m_leftDown;
    m_middleDown = event.m_middleDown;
    m_rightDown = event.m_rightDown;
    m_aux1Down = event.m_aux1Down;
    m_aux2Down = event.m_aux2Down;

    m_wheelRotation = event.m_wheelRotation;
    m_wheelDelta = event.m_wheelDelta;
    m_wheelInverted = event.m_wheelInverted;
    m_linesPerAction = event.m_linesPerAction;
    m_columnsPerAction = event.m_columnsPerAction;
    m_wheelAxis = event.m_wheelAxis;

    m_magnification = event.m_magnification;
}

// return true if was a button dclick event
bool wxMouseEvent::ButtonDClick(int but) const
{
    switch (but)
    {
        default:
            wxFAIL_MSG(wxT("invalid parameter in wxMouseEvent::ButtonDClick"));
            wxFALLTHROUGH;

        case wxMOUSE_BTN_ANY:
            return (LeftDClick() || MiddleDClick() || RightDClick() ||
                    Aux1DClick() || Aux2DClick());

        case wxMOUSE_BTN_LEFT:
            return LeftDClick();

        case wxMOUSE_BTN_MIDDLE:
            return MiddleDClick();

        case wxMOUSE_BTN_RIGHT:
            return RightDClick();

        case wxMOUSE_BTN_AUX1:
            return Aux1DClick();

        case wxMOUSE_BTN_AUX2:
            return Aux2DClick();
    }
}

// return true if was a button down event
bool wxMouseEvent::ButtonDown(int but) const
{
    switch (but)
    {
        default:
            wxFAIL_MSG(wxT("invalid parameter in wxMouseEvent::ButtonDown"));
            wxFALLTHROUGH;

        case wxMOUSE_BTN_ANY:
            return (LeftDown() || MiddleDown() || RightDown() ||
                    Aux1Down() || Aux2Down());

        case wxMOUSE_BTN_LEFT:
            return LeftDown();

        case wxMOUSE_BTN_MIDDLE:
            return MiddleDown();

        case wxMOUSE_BTN_RIGHT:
            return RightDown();

        case wxMOUSE_BTN_AUX1:
            return Aux1Down();

        case wxMOUSE_BTN_AUX2:
            return Aux2Down();
    }
}

// return true if was a button up event
bool wxMouseEvent::ButtonUp(int but) const
{
    switch (but)
    {
        default:
            wxFAIL_MSG(wxT("invalid parameter in wxMouseEvent::ButtonUp"));
            wxFALLTHROUGH;

        case wxMOUSE_BTN_ANY:
            return (LeftUp() || MiddleUp() || RightUp() ||
                    Aux1Up() || Aux2Up());

        case wxMOUSE_BTN_LEFT:
            return LeftUp();

        case wxMOUSE_BTN_MIDDLE:
            return MiddleUp();

        case wxMOUSE_BTN_RIGHT:
            return RightUp();

        case wxMOUSE_BTN_AUX1:
            return Aux1Up();

        case wxMOUSE_BTN_AUX2:
            return Aux2Up();
    }
}

// return true if the given button is currently changing state
bool wxMouseEvent::Button(int but) const
{
    switch (but)
    {
        default:
            wxFAIL_MSG(wxT("invalid parameter in wxMouseEvent::Button"));
            wxFALLTHROUGH;

        case wxMOUSE_BTN_ANY:
            return ButtonUp(wxMOUSE_BTN_ANY) ||
                    ButtonDown(wxMOUSE_BTN_ANY) ||
                        ButtonDClick(wxMOUSE_BTN_ANY);

        case wxMOUSE_BTN_LEFT:
            return LeftDown() || LeftUp() || LeftDClick();

        case wxMOUSE_BTN_MIDDLE:
            return MiddleDown() || MiddleUp() || MiddleDClick();

        case wxMOUSE_BTN_RIGHT:
            return RightDown() || RightUp() || RightDClick();

        case wxMOUSE_BTN_AUX1:
           return Aux1Down() || Aux1Up() || Aux1DClick();

        case wxMOUSE_BTN_AUX2:
           return Aux2Down() || Aux2Up() || Aux2DClick();
    }
}

int wxMouseEvent::GetButton() const
{
    for ( int i = 1; i < wxMOUSE_BTN_MAX; i++ )
    {
        if ( Button(i) )
        {
            return i;
        }
    }

    return wxMOUSE_BTN_NONE;
}

// Find the logical position of the event given the DC
wxPoint wxMouseEvent::GetLogicalPosition(const wxDC& dc) const
{
    wxPoint pt(dc.DeviceToLogicalX(m_x), dc.DeviceToLogicalY(m_y));
    return pt;
}

// ----------------------------------------------------------------------------
// wxKeyEvent
// ----------------------------------------------------------------------------

wxKeyEvent::wxKeyEvent(wxEventType type)
    : m_uniChar(WXK_NONE)
{
    m_eventType = type;
    m_keyCode = WXK_NONE;

    m_x =
    m_y = wxDefaultCoord;

    InitPropagation();
}

wxKeyEvent::wxKeyEvent(const wxKeyEvent& evt)
          : wxEvent(evt),
            wxKeyboardState(evt)
{
    DoAssignMembers(evt);

    InitPropagation();
}

wxKeyEvent::wxKeyEvent(wxEventType eventType, const wxKeyEvent& evt)
          : wxEvent(evt),
            wxKeyboardState(evt)
{
    DoAssignMembers(evt);

    m_eventType = eventType;

    InitPropagation();
}

wxKeyEvent& wxKeyEvent::operator=(const wxKeyEvent& evt)
{
    if ( &evt != this )
    {
        wxEvent::operator=(evt);
        wxKeyboardState::operator=(evt);

        DoAssignMembers(evt);
    }
    return *this;
}

void wxKeyEvent::InitPositionIfNecessary() const
{
    if ( m_hasPosition )
        return;

    // We're const because we're called from const Get[XY]() methods but we
    // need to update the "cached" values.
    wxKeyEvent& self = const_cast<wxKeyEvent&>(*this);
    self.m_hasPosition = true;

    // The only position we can possibly associate with the keyboard event on
    // the platforms where it doesn't carry it already is the mouse position.
    wxGetMousePosition(&self.m_x, &self.m_y);

    // If this event is associated with a window, the position should be in its
    // client coordinates, but otherwise leave it in screen coordinates as what
    // else can we use?
    wxWindow* const win = wxDynamicCast(GetEventObject(), wxWindow);
    if ( win )
        win->ScreenToClient(&self.m_x, &self.m_y);
}

wxCoord wxKeyEvent::GetX() const
{
    InitPositionIfNecessary();

    return m_x;
}

wxCoord wxKeyEvent::GetY() const
{
    InitPositionIfNecessary();

    return m_y;
}

bool wxKeyEvent::IsKeyInCategory(int category) const
{
    switch ( GetKeyCode() )
    {
        case WXK_LEFT:
        case WXK_RIGHT:
        case WXK_UP:
        case WXK_DOWN:
        case WXK_NUMPAD_LEFT:
        case WXK_NUMPAD_RIGHT:
        case WXK_NUMPAD_UP:
        case WXK_NUMPAD_DOWN:
            return (category & WXK_CATEGORY_ARROW) != 0;

        case WXK_PAGEDOWN:
        case WXK_PAGEUP:
        case WXK_NUMPAD_PAGEUP:
        case WXK_NUMPAD_PAGEDOWN:
            return (category & WXK_CATEGORY_PAGING) != 0;

        case WXK_HOME:
        case WXK_END:
        case WXK_NUMPAD_HOME:
        case WXK_NUMPAD_END:
            return (category & WXK_CATEGORY_JUMP) != 0;

        case WXK_TAB:
            // We have to make an extra check for this one, as it's a synonym
            // for Ctrl-I, but we don't want to recognize Ctrl-I as a TAB key.
            // As raw key codes are platform-dependent we have to do it in
            // platform-specific way.
#ifdef __WXMSW__
            // Under Windows the native WM_CHAR already does the translation
            // and so we need to look at the scan code, which is part of the
            // flags, rather than the key code itself.
            if ( ((GetRawKeyFlags() >> 16) & 0xff) == 0x17 )
            {
                return false;
            }
#else // !__WXMSW__
            // For the other platforms we can use the raw key code, but it's
            // still different, with Mac doing its own thing. We assume all the
            // other platforms do as GTK does and use either "I" or "i" for
            // this letter events.
            switch ( GetRawKeyCode() )
            {
#ifdef __WXOSX__
                case 0x22: // kVK_ANSI_I
#else
                case 'I':
                case 'i':
#endif
                    return false;
            }
#endif // __WXMSW__/!__WXMSW__
            wxFALLTHROUGH;
        case WXK_NUMPAD_TAB:
            return (category & WXK_CATEGORY_TAB) != 0;

        case WXK_BACK:
            // See the comment above for TAB.
#ifdef __WXMSW__
            if ( ((GetRawKeyFlags() >> 16) & 0xff) == 0x23 )
            {
                return false;
            }
#else // !__WXMSW__
            switch ( GetRawKeyCode() )
            {
#ifdef __WXOSX__
                case 0x04: // kVK_ANSI_H
#else
                case 'H':
                case 'h':
#endif
                    return false;
            }
#endif // __WXMSW__/!__WXMSW__
            wxFALLTHROUGH;
        case WXK_DELETE:
        case WXK_NUMPAD_DELETE:
            return (category & WXK_CATEGORY_CUT) != 0;

        default:
            return false;
    }
}

// ----------------------------------------------------------------------------
// wxWindowCreateEvent
// ----------------------------------------------------------------------------

wxWindowCreateEvent::wxWindowCreateEvent(wxWindow *win)
{
    SetEventType(wxEVT_CREATE);
    SetEventObject(win);
}

// ----------------------------------------------------------------------------
// wxWindowDestroyEvent
// ----------------------------------------------------------------------------

wxWindowDestroyEvent::wxWindowDestroyEvent(wxWindow *win)
{
    SetEventType(wxEVT_DESTROY);
    SetEventObject(win);
}

// ----------------------------------------------------------------------------
// wxChildFocusEvent
// ----------------------------------------------------------------------------

wxChildFocusEvent::wxChildFocusEvent(wxWindow *win)
                 : wxCommandEvent(wxEVT_CHILD_FOCUS)
{
    SetEventObject(win);
}

// ----------------------------------------------------------------------------
// wxHelpEvent
// ----------------------------------------------------------------------------

/* static */
wxHelpEvent::Origin wxHelpEvent::GuessOrigin(Origin origin)
{
    if ( origin == Origin_Unknown )
    {
        // assume that the event comes from the help button if it's not from
        // keyboard and that pressing F1 always results in the help event
        origin = wxGetKeyState(WXK_F1) ? Origin_Keyboard : Origin_HelpButton;
    }

    return origin;
}

// ----------------------------------------------------------------------------
// wxDPIChangedEvent
// ----------------------------------------------------------------------------

wxPoint wxDPIChangedEvent::Scale(wxPoint pt) const
{
    return wxRescaleCoord(pt).From(m_oldDPI).To(m_newDPI);
}

wxSize wxDPIChangedEvent::Scale(wxSize sz) const
{
    return wxRescaleCoord(sz).From(m_oldDPI).To(m_newDPI);
}

#endif // wxUSE_GUI


#if wxUSE_BASE

// ----------------------------------------------------------------------------
// wxEventHashTable
// ----------------------------------------------------------------------------

static const int EVENT_TYPE_TABLE_INIT_SIZE = 31; // Not too big not too small...

wxEventHashTable* wxEventHashTable::sm_first = nullptr;

wxEventHashTable::wxEventHashTable(const wxEventTable &table)
                : m_table(table),
                  m_rebuildHash(true)
{
    AllocEventTypeTable(EVENT_TYPE_TABLE_INIT_SIZE);

    m_next = sm_first;
    if (m_next)
        m_next->m_previous = this;
    sm_first = this;
}

wxEventHashTable::~wxEventHashTable()
{
    if (m_next)
        m_next->m_previous = m_previous;
    if (m_previous)
        m_previous->m_next = m_next;
    if (sm_first == this)
        sm_first = m_next;

    Clear();
}

void wxEventHashTable::Clear()
{
    for ( size_t i = 0; i < m_size; i++ )
    {
        EventTypeTablePointer  eTTnode = m_eventTypeTable[i];
        delete eTTnode;
    }

    wxDELETEA(m_eventTypeTable);

    m_size = 0;
}

bool wxEventHashTable::HandleEvent(wxEvent &event, wxEvtHandler *self)
{
    if (m_rebuildHash)
    {
        InitHashTable();
        m_rebuildHash = false;
    }

    if (!m_eventTypeTable)
        return false;

    // Find all entries for the given event type.
    wxEventType eventType = event.GetEventType();
    const EventTypeTablePointer eTTnode = m_eventTypeTable[eventType % m_size];
    if (eTTnode && eTTnode->eventType == eventType)
    {
        // Now start the search for an event handler
        // that can handle an event with the given ID.
        const wxEventTableEntryPointerArray&
            eventEntryTable = eTTnode->eventEntryTable;

        const size_t count = eventEntryTable.GetCount();
        for (size_t n = 0; n < count; n++)
        {
            const wxEventTableEntry& entry = *eventEntryTable[n];
            if ( wxEvtHandler::ProcessEventIfMatchesId(entry, self, event) )
                return true;
        }
    }

    return false;
}

void wxEventHashTable::InitHashTable()
{
    // Loop over the event tables and all its base tables.
    const wxEventTable *table = &m_table;
    while (table)
    {
        // Retrieve all valid event handler entries
        const wxEventTableEntry *entry = table->entries;
        while (entry->m_fn != nullptr)
        {
            // Add the event entry in the Hash.
            AddEntry(*entry);

            entry++;
        }

        table = table->baseTable;
    }

    // Let's free some memory.
    size_t i;
    for(i = 0; i < m_size; i++)
    {
        EventTypeTablePointer  eTTnode = m_eventTypeTable[i];
        if (eTTnode)
        {
            eTTnode->eventEntryTable.Shrink();
        }
    }
}

void wxEventHashTable::AddEntry(const wxEventTableEntry &entry)
{
    // This might happen 'accidentally' as the app is exiting
    if (!m_eventTypeTable)
        return;

    EventTypeTablePointer *peTTnode = &m_eventTypeTable[entry.m_eventType % m_size];
    EventTypeTablePointer  eTTnode = *peTTnode;

    if (eTTnode)
    {
        if (eTTnode->eventType != entry.m_eventType)
        {
            // Resize the table!
            GrowEventTypeTable();
            // Try again to add it.
            AddEntry(entry);
            return;
        }
    }
    else
    {
        eTTnode = new EventTypeTable;
        eTTnode->eventType = entry.m_eventType;
        *peTTnode = eTTnode;
    }

    // Fill all hash entries between entry.m_id and entry.m_lastId...
    eTTnode->eventEntryTable.Add(&entry);
}

void wxEventHashTable::AllocEventTypeTable(size_t size)
{
    m_eventTypeTable = new EventTypeTablePointer[size];
    memset((void *)m_eventTypeTable, 0, sizeof(EventTypeTablePointer)*size);
    m_size = size;
}

void wxEventHashTable::GrowEventTypeTable()
{
    size_t oldSize = m_size;
    EventTypeTablePointer *oldEventTypeTable = m_eventTypeTable;

    // TODO: Search the most optimal grow sequence
    AllocEventTypeTable(/* GetNextPrime(oldSize) */oldSize*2+1);

    for ( size_t i = 0; i < oldSize; /* */ )
    {
        EventTypeTablePointer  eTToldNode = oldEventTypeTable[i];
        if (eTToldNode)
        {
            EventTypeTablePointer *peTTnode = &m_eventTypeTable[eTToldNode->eventType % m_size];
            EventTypeTablePointer  eTTnode = *peTTnode;

            // Check for collision, we don't want any.
            if (eTTnode)
            {
                GrowEventTypeTable();
                continue; // Don't increment the counter,
                          // as we still need to add this element.
            }
            else
            {
                // Get the old value and put it in the new table.
                *peTTnode = oldEventTypeTable[i];
            }
        }

        i++;
    }

    delete[] oldEventTypeTable;
}

// ----------------------------------------------------------------------------
// wxEvtHandler
// ----------------------------------------------------------------------------

wxEvtHandler::wxEvtHandler()
{
    m_nextHandler = nullptr;
    m_previousHandler = nullptr;
    m_enabled = true;
    m_dynamicEvents = nullptr;
    m_pendingEvents = nullptr;

    // no client data (yet)
    m_clientData = nullptr;
    m_clientDataType = wxClientData_None;
}

wxEvtHandler::~wxEvtHandler()
{
    Unlink();

    if (m_dynamicEvents)
    {
        size_t cookie;
        for ( wxDynamicEventTableEntry* entry = GetFirstDynamicEntry(cookie);
              entry;
              entry = GetNextDynamicEntry(cookie) )
        {
            // Remove ourselves from sink destructor notifications
            // (this has usually been done, in wxTrackable destructor)
            wxEvtHandler *eventSink = entry->m_fn->GetEvtHandler();
            if ( eventSink )
            {
                wxEventConnectionRef * const
                    evtConnRef = FindRefInTrackerList(eventSink);
                if ( evtConnRef )
                {
                    eventSink->RemoveNode(evtConnRef);
                    delete evtConnRef;
                }
            }

            delete entry->m_callbackUserData;
            delete entry;
        }
        delete m_dynamicEvents;
    }

    // Remove us from the list of the pending events if necessary.
    if (wxTheApp)
        wxTheApp->RemovePendingEventHandler(this);

    DeletePendingEvents();

    // we only delete object data, not untyped
    if ( m_clientDataType == wxClientData_Object )
        delete m_clientObject;
}

void wxEvtHandler::Unlink()
{
    // this event handler must take itself out of the chain of handlers:

    if (m_previousHandler)
        m_previousHandler->SetNextHandler(m_nextHandler);

    if (m_nextHandler)
        m_nextHandler->SetPreviousHandler(m_previousHandler);

    m_nextHandler = nullptr;
    m_previousHandler = nullptr;
}

bool wxEvtHandler::IsUnlinked() const
{
    return m_previousHandler == nullptr &&
           m_nextHandler == nullptr;
}

wxEventFilter* wxEvtHandler::ms_filterList = nullptr;

/* static */ void wxEvtHandler::AddFilter(wxEventFilter* filter)
{
    wxCHECK_RET( filter, "null filter" );

    filter->m_next = ms_filterList;
    ms_filterList = filter;
}

/* static */ void wxEvtHandler::RemoveFilter(wxEventFilter* filter)
{
    wxEventFilter* prev = nullptr;
    for ( wxEventFilter* f = ms_filterList; f; f = f->m_next )
    {
        if ( f == filter )
        {
            // Set the previous list element or the list head to the next
            // element.
            if ( prev )
                prev->m_next = f->m_next;
            else
                ms_filterList = f->m_next;

            // Also reset the next pointer in the filter itself just to avoid
            // having possibly dangling pointers, even though it's not strictly
            // necessary.
            f->m_next = nullptr;

            // Skip the assert below.
            return;
        }

        prev = f;
    }

    wxFAIL_MSG( "Filter not found" );
}

#if wxUSE_THREADS

bool wxEvtHandler::ProcessThreadEvent(const wxEvent& event)
{
    // check that we are really in a child thread
    wxASSERT_MSG( !wxThread::IsMain(),
                  wxT("use ProcessEvent() in main thread") );

    AddPendingEvent(event);

    return true;
}

#endif // wxUSE_THREADS

void wxEvtHandler::QueueEvent(wxEvent *event)
{
    wxCHECK_RET( event, "null event can't be posted" );

    if (!wxTheApp)
    {
        // we need an event loop which manages the list of event handlers with
        // pending events... cannot proceed without it!
        wxLogDebug("No application object! Cannot queue this event!");

        // anyway delete the given event to avoid memory leaks
        delete event;

        return;
    }

    // 1) Add this event to our list of pending events
    wxENTER_CRIT_SECT( m_pendingEventsLock );

    if ( !m_pendingEvents )
        m_pendingEvents = new wxList;

    m_pendingEvents->Append(event);

    // 2) Add this event handler to list of event handlers that
    //    have pending events.

    wxTheApp->AppendPendingEventHandler(this);

    // only release m_pendingEventsLock now because otherwise there is a race
    // condition as described in the ticket #9093: we could process the event
    // just added to m_pendingEvents in our ProcessPendingEvents() below before
    // we had time to append this pointer to wxHandlersWithPendingEvents list; thus
    // breaking the invariant that a handler should be in the list iff it has
    // any pending events to process
    wxLEAVE_CRIT_SECT( m_pendingEventsLock );

    // 3) Inform the system that new pending events are somewhere,
    //    and that these should be processed in idle time.
    wxWakeUpIdle();
}

void wxEvtHandler::DeletePendingEvents()
{
    if (m_pendingEvents)
        m_pendingEvents->DeleteContents(true);
    wxDELETE(m_pendingEvents);
}

void wxEvtHandler::ProcessPendingEvents()
{
    if (!wxTheApp)
    {
        // we need an event loop which manages the list of event handlers with
        // pending events... cannot proceed without it!
        wxLogDebug("No application object! Cannot process pending events!");
        return;
    }

    // we need to process only a single pending event in this call because
    // each call to ProcessEvent() could result in the destruction of this
    // same event handler (see the comment at the end of this function)

    wxENTER_CRIT_SECT( m_pendingEventsLock );

    // this method is only called by wxApp if this handler does have
    // pending events
    wxCHECK_RET( m_pendingEvents && !m_pendingEvents->IsEmpty(),
                 "should have pending events if called" );

    wxList::compatibility_iterator node = m_pendingEvents->GetFirst();
    wxEvent* pEvent = static_cast<wxEvent *>(node->GetData());

    // find the first event which can be processed now:
    wxEventLoopBase* evtLoop = wxEventLoopBase::GetActive();
    if (evtLoop && evtLoop->IsYielding())
    {
        while (node && pEvent && !evtLoop->IsEventAllowedInsideYield(pEvent->GetEventCategory()))
        {
            node = node->GetNext();
            pEvent = node ? static_cast<wxEvent *>(node->GetData()) : nullptr;
        }

        if (!node)
        {
            // all our events are NOT processable now... signal this:
            wxTheApp->DelayPendingEventHandler(this);

            // see the comment at the beginning of evtloop.h header for the
            // logic behind YieldFor() and behind DelayPendingEventHandler()

            wxLEAVE_CRIT_SECT( m_pendingEventsLock );

            return;
        }
    }

    std::unique_ptr<wxEvent> event(pEvent);

    // it's important we remove event from list before processing it, else a
    // nested event loop, for example from a modal dialog, might process the
    // same event again.
    m_pendingEvents->Erase(node);

    if ( m_pendingEvents->IsEmpty() )
    {
        // if there are no more pending events left, we don't need to
        // stay in this list
        wxTheApp->RemovePendingEventHandler(this);
    }

    wxLEAVE_CRIT_SECT( m_pendingEventsLock );

    // We must not let exceptions escape from here, there is no outer exception
    // handler to catch them and so letting them do it would just terminate the
    // program.
    SafelyProcessEvent(*event);

    // careful: this object could have been deleted by the event handler
    // executed by the above ProcessEvent() call, so we can't access any fields
    // of this object any more
}

/* static */
bool wxEvtHandler::ProcessEventIfMatchesId(const wxEventTableEntryBase& entry,
                                           wxEvtHandler *handler,
                                           wxEvent& event)
{
    int tableId1 = entry.m_id,
        tableId2 = entry.m_lastId;

    // match only if the event type is the same and the id is either -1 in
    // the event table (meaning "any") or the event id matches the id
    // specified in the event table either exactly or by falling into
    // range between first and last
    if ((tableId1 == wxID_ANY) ||
        (tableId2 == wxID_ANY && tableId1 == event.GetId()) ||
        (tableId2 != wxID_ANY &&
         (event.GetId() >= tableId1 && event.GetId() <= tableId2)))
    {
        event.Skip(false);
        event.m_callbackUserData = entry.m_callbackUserData;

#if wxUSE_EXCEPTIONS
        if ( wxTheApp )
        {
            // call the handler via wxApp method which allows the user to catch
            // any exceptions which may be thrown by any handler in the program
            // in one place
            wxTheApp->CallEventHandler(handler, *entry.m_fn, event);
        }
        else
#endif // wxUSE_EXCEPTIONS
        {
            (*entry.m_fn)(handler, event);
        }

        if (!event.GetSkipped())
            return true;
    }

    return false;
}

bool wxEvtHandler::DoTryApp(wxEvent& event)
{
    if ( wxTheApp && (this != wxTheApp) )
    {
        // Special case: don't pass wxEVT_IDLE to wxApp, since it'll always
        // swallow it. wxEVT_IDLE is sent explicitly to wxApp so it will be
        // processed appropriately via SearchEventTable.
        if ( event.GetEventType() != wxEVT_IDLE )
        {
            if ( wxTheApp->ProcessEvent(event) )
                return true;
        }
    }

    return false;
}

bool wxEvtHandler::TryBefore(wxEvent& event)
{
    wxUnusedVar(event);
    return false;
}

bool wxEvtHandler::TryAfter(wxEvent& event)
{
    // We only want to pass the window to the application object once even if
    // there are several chained handlers. Ensure that this is what happens by
    // only calling DoTryApp() if there is no next handler (which would do it).
    //
    // Notice that, unlike simply calling TryAfter() on the last handler in the
    // chain only from ProcessEvent(), this also works with wxWindow object in
    // the middle of the chain: its overridden TryAfter() will still be called
    // and propagate the event upwards the window hierarchy even if it's not
    // the last one in the chain (which, admittedly, shouldn't happen often).
    if ( GetNextHandler() )
        return GetNextHandler()->TryAfter(event);

    // If this event is going to be processed in another handler next, don't
    // pass it to wxTheApp now, it will be done from TryAfter() of this other
    // handler.
    if ( event.WillBeProcessedAgain() )
        return false;

    return DoTryApp(event);
}

bool wxEvtHandler::ProcessEvent(wxEvent& event)
{
    // The very first thing we do is to allow any registered filters to hook
    // into event processing in order to globally pre-process all events.
    //
    // Note that we should only do it if we're the first event handler called
    // to avoid calling FilterEvent() multiple times as the event goes through
    // the event handler chain and possibly upwards the window hierarchy.
    if ( !event.WasProcessed() )
    {
        for ( wxEventFilter* f = ms_filterList; f; f = f->m_next )
        {
            int rc = f->FilterEvent(event);
            if ( rc != wxEventFilter::Event_Skip )
            {
                wxASSERT_MSG( rc == wxEventFilter::Event_Ignore ||
                                rc == wxEventFilter::Event_Processed,
                              "unexpected FilterEvent() return value" );

                return rc != wxEventFilter::Event_Ignore;
            }
            //else: proceed normally
        }
    }

    // Short circuit the event processing logic if we're requested to process
    // this event in this handler only, see DoTryChain() for more details.
    if ( event.ShouldProcessOnlyIn(this) )
        return TryBeforeAndHere(event);


    // Try to process the event in this handler itself.
    if ( ProcessEventLocally(event) )
    {
        // It is possible that DoTryChain() called from ProcessEventLocally()
        // returned true but the event was not really processed: this happens
        // if a custom handler ignores the request to process the event in this
        // handler only and in this case we should skip the post processing
        // done in TryAfter() but still return the correct value ourselves to
        // indicate whether we did or did not find a handler for this event.
        return !event.GetSkipped();
    }

    // If we still didn't find a handler, propagate the event upwards the
    // window chain and/or to the application object.
    if ( TryAfter(event) )
        return true;


    // No handler found anywhere, bail out.
    return false;
}

bool wxEvtHandler::ProcessEventLocally(wxEvent& event)
{
    // Try the hooks which should be called before our own handlers and this
    // handler itself first. Notice that we should not call ProcessEvent() on
    // this one as we're already called from it, which explains why we do it
    // here and not in DoTryChain()
    return TryBeforeAndHere(event) || DoTryChain(event);
}

bool wxEvtHandler::DoTryChain(wxEvent& event)
{
    for ( wxEvtHandler *h = GetNextHandler(); h; h = h->GetNextHandler() )
    {
        // We need to process this event at the level of this handler only
        // right now, the pre-/post-processing was either already done by
        // ProcessEvent() from which we were called or will be done by it when
        // we return.
        //
        // However we must call ProcessEvent() and not TryHereOnly() because the
        // existing code (including some in wxWidgets itself) expects the
        // overridden ProcessEvent() in its custom event handlers pushed on a
        // window to be called.
        //
        // So we must call ProcessEvent() but it must not do what it usually
        // does. To resolve this paradox we set up a special flag inside the
        // object itself to let ProcessEvent() know that it shouldn't do any
        // pre/post-processing for this event if it gets it. Note that this
        // only applies to this handler, if the event is passed to another one
        // by explicitly calling its ProcessEvent(), pre/post-processing should
        // be done as usual.
        //
        // Final complication is that if the implementation of ProcessEvent()
        // called wxEvent::DidntHonourProcessOnlyIn() (as the gross hack that
        // is wxScrollHelperEvtHandler::ProcessEvent() does) and ignored our
        // request to process event in this handler only, we have to compensate
        // for it by not processing the event further because this was already
        // done by that rogue event handler.
        wxEventProcessInHandlerOnly processInHandlerOnly(event, h);
        if ( h->ProcessEvent(event) )
        {
            // Make sure "skipped" flag is not set as the event was really
            // processed in this case. Normally it shouldn't be set anyhow but
            // make sure just in case the user code does something strange.
            event.Skip(false);

            return true;
        }

        if ( !event.ShouldProcessOnlyIn(h) )
        {
            // Still return true to indicate that no further processing should
            // be undertaken but ensure that "skipped" flag is set so that the
            // caller knows that the event was not really processed.
            event.Skip();

            return true;
        }
    }

    return false;
}

bool wxEvtHandler::TryHereOnly(wxEvent& event)
{
    // If the event handler is disabled it doesn't process any events
    if ( !GetEvtHandlerEnabled() )
        return false;

    // Handle per-instance dynamic event tables first
    if ( m_dynamicEvents && SearchDynamicEventTable(event) )
        return true;

    // Then static per-class event tables
    if ( GetEventHashTable().HandleEvent(event, this) )
        return true;

    // There is an implicit entry for async method calls processing in every
    // event handler:
    if ( event.GetEventType() == wxEVT_ASYNC_METHOD_CALL &&
            event.GetEventObject() == this )
    {
        static_cast<wxAsyncMethodCallEvent&>(event).Execute();
        return true;
    }

    // We don't have a handler for this event.
    return false;
}

bool wxEvtHandler::SafelyProcessEvent(wxEvent& event)
{
#if wxUSE_EXCEPTIONS
    try
    {
#endif
        return ProcessEvent(event);
#if wxUSE_EXCEPTIONS
    }
    catch ( ... )
    {
        WXConsumeException();

        return false;
    }
#endif // wxUSE_EXCEPTIONS
}

#if wxUSE_EXCEPTIONS
/* static */
void wxEvtHandler::WXConsumeException()
{
    wxEventLoopBase * const loop = wxEventLoopBase::GetActive();
    try
    {
        if ( !wxTheApp || !wxTheApp->OnExceptionInMainLoop() )
        {
            // If OnExceptionInMainLoop() returns false, we're supposed to exit
            // the program and for this we need to exit the main loop, not the
            // possibly nested one we're running right now.
            if ( wxTheApp )
            {
                wxTheApp->ExitMainLoop();
            }
            else
            {
                // We must not continue running after an exception, unless
                // explicitly requested, so if we can't ensure this in any
                // other way, do it brutally like this.
                wxAbort();
            }

        }
        //else: continue running current event loop
    }
    catch ( ... )
    {
        // OnExceptionInMainLoop() threw, possibly rethrowing the same
        // exception again. We have to deal with it here because we can't
        // allow the exception to escape from the handling code, this will
        // result in a crash at best (e.g. when using wxGTK as C++
        // exceptions can't propagate through the C GTK+ code and corrupt
        // the stack) and in something even more weird at worst (like
        // exceptions completely disappearing into the void under some
        // 64 bit versions of Windows).
        if ( loop && !loop->IsYielding() )
            loop->Exit();

        // Give the application one last possibility to store the exception
        // for rethrowing it later, when we get back to our code.
        bool stored = false;
        try
        {
            if ( wxTheApp )
                stored = wxTheApp->StoreCurrentException();
        }
        catch ( ... )
        {
            // StoreCurrentException() really shouldn't throw, but if it
            // did, take it as an indication that it didn't store it.
        }

        // If it didn't take it, just abort, at least like this we behave
        // consistently everywhere.
        if ( !stored )
        {
            try
            {
                if ( wxTheApp )
                    wxTheApp->OnUnhandledException();
            }
            catch ( ... )
            {
                // And OnUnhandledException() absolutely shouldn't throw,
                // but we still must account for the possibility that it
                // did. At least show some information about the exception
                // in this case.
                wxTheApp->wxAppConsoleBase::OnUnhandledException();
            }

            wxAbort();
        }
    }
}

#endif // wxUSE_EXCEPTIONS

bool wxEvtHandler::SearchEventTable(wxEventTable& table, wxEvent& event)
{
    const wxEventType eventType = event.GetEventType();
    for ( int i = 0; table.entries[i].m_fn != nullptr; i++ )
    {
        const wxEventTableEntry& entry = table.entries[i];
        if ( eventType == entry.m_eventType )
        {
            if ( ProcessEventIfMatchesId(entry, this, event) )
                return true;
        }
    }

    return false;
}

void wxEvtHandler::DoBind(int id,
                          int lastId,
                          wxEventType eventType,
                          wxEventFunctor *func,
                          wxObject *userData)
{
    wxDynamicEventTableEntry *entry =
        new wxDynamicEventTableEntry(eventType, id, lastId, func, userData);

    // Check if the derived class allows binding such event handlers.
    if ( !OnDynamicBind(*entry) )
    {
        delete entry;
        return;
    }

    if (!m_dynamicEvents)
        m_dynamicEvents = new DynamicEvents;

    // We prefer to push back the entry here and then iterate over the vector
    // in reverse direction in GetNextDynamicEntry() as it's more efficient
    // than inserting the element at the front.
    m_dynamicEvents->push_back(entry);

    // Make sure we get to know when a sink is destroyed
    wxEvtHandler *eventSink = func->GetEvtHandler();
    if ( eventSink && eventSink != this )
    {
        wxEventConnectionRef *evtConnRef = FindRefInTrackerList(eventSink);
        if ( evtConnRef )
            evtConnRef->IncRef( );
        else
            new wxEventConnectionRef(this, eventSink);
    }
}

bool
wxEvtHandler::DoUnbind(int id,
                       int lastId,
                       wxEventType eventType,
                       const wxEventFunctor& func,
                       wxObject *userData)
{
    if (!m_dynamicEvents)
        return false;

    size_t cookie;
    for ( wxDynamicEventTableEntry* entry = GetFirstDynamicEntry(cookie);
          entry;
          entry = GetNextDynamicEntry(cookie) )
    {
        if ((entry->m_id == id) &&
            ((entry->m_lastId == lastId) || (lastId == wxID_ANY)) &&
            ((entry->m_eventType == eventType) || (eventType == wxEVT_NULL)) &&
            entry->m_fn->IsMatching(func) &&
            ((entry->m_callbackUserData == userData) || !userData))
        {
            // Remove connection from tracker node (wxEventConnectionRef)
            wxEvtHandler *eventSink = entry->m_fn->GetEvtHandler();
            if ( eventSink && eventSink != this )
            {
                wxEventConnectionRef *evtConnRef = FindRefInTrackerList(eventSink);
                if ( evtConnRef )
                    evtConnRef->DecRef();
            }

            delete entry->m_callbackUserData;

            // We can't delete the entry from the vector if we're currently
            // iterating over it. As we don't know whether we're or not, just
            // null it for now and we will really erase it when we do finish
            // iterating over it the next time.
            //
            // Notice that we rely on "cookie" being just the index into the
            // vector, which is not guaranteed by our API, but here we can use
            // this implementation detail.
            (*m_dynamicEvents)[cookie] = nullptr;

            delete entry;
            return true;
        }
    }
    return false;
}

wxDynamicEventTableEntry*
wxEvtHandler::GetFirstDynamicEntry(size_t& cookie) const
{
    if ( !m_dynamicEvents )
        return nullptr;

    // The handlers are in LIFO order, so we must start at the end.
    cookie = m_dynamicEvents->size();
    return GetNextDynamicEntry(cookie);
}

wxDynamicEventTableEntry*
wxEvtHandler::GetNextDynamicEntry(size_t& cookie) const
{
    // On entry here cookie is one greater than the index of the entry to
    // return, so if it is 0, it means that there are no more entries.
    while ( cookie )
    {
        // Otherwise return the element at the previous index, skipping any
        // null elements which indicate removed entries.
        wxDynamicEventTableEntry* const entry = m_dynamicEvents->at(--cookie);
        if ( entry )
            return entry;
    }

    return nullptr;
}

bool wxEvtHandler::SearchDynamicEventTable( wxEvent& event )
{
    wxCHECK_MSG( m_dynamicEvents, false,
                 wxT("caller should check that we have dynamic events") );

    DynamicEvents& dynamicEvents = *m_dynamicEvents;

    bool needToPruneDeleted = false;

    // We can't use Get{First,Next}DynamicEntry() here as they hide the deleted
    // but not yet pruned entries from the caller, but here we do want to know
    // about them, so iterate directly. Remember to do it in the reverse order
    // to honour the order of handlers connection.
    for ( size_t n = dynamicEvents.size(); n; n-- )
    {
        wxDynamicEventTableEntry* const entry = dynamicEvents[n - 1];

        if ( !entry )
        {
            // This entry must have been unbound at some time in the past, so
            // skip it now and really remove it from the vector below, once we
            // finish iterating.
            needToPruneDeleted = true;
            continue;
        }

        if ( event.GetEventType() == entry->m_eventType )
        {
            wxEvtHandler *handler = entry->m_fn->GetEvtHandler();
            if ( !handler )
               handler = this;
            if ( ProcessEventIfMatchesId(*entry, handler, event) )
            {
                // It's important to skip pruning of the unbound event entries
                // below because this object itself could have been deleted by
                // the event handler making m_dynamicEvents a dangling pointer
                // which can't be accessed any longer in the code below.
                //
                // In practice, it hopefully shouldn't be a problem to wait
                // until we get an event that we don't handle before pruning
                // because this should happen soon enough and even if it
                // doesn't the worst possible outcome is slightly increased
                // memory consumption while not skipping pruning can result in
                // hard to reproduce (because they require the disconnection
                // and deletion happen at the same time which is not always the
                // case) crashes.
                return true;
            }
        }
    }

    if ( needToPruneDeleted )
    {
        size_t nNew = 0;
        for ( size_t n = 0; n != dynamicEvents.size(); n++ )
        {
            if ( dynamicEvents[n] )
                dynamicEvents[nNew++] = dynamicEvents[n];
        }

        wxASSERT( nNew != dynamicEvents.size() );
        dynamicEvents.resize(nNew);
    }

    return false;
}

void wxEvtHandler::DoSetClientObject( wxClientData *data )
{
    wxASSERT_MSG( m_clientDataType != wxClientData_Void,
                  wxT("can't have both object and void client data") );

    delete m_clientObject;

    m_clientObject = data;
    m_clientDataType = wxClientData_Object;
}

wxClientData *wxEvtHandler::DoGetClientObject() const
{
    // it's not an error to call GetClientObject() on a window which doesn't
    // have client data at all - nullptr will be returned
    wxASSERT_MSG( m_clientDataType != wxClientData_Void,
                  wxT("this window doesn't have object client data") );

    return m_clientObject;
}

void wxEvtHandler::DoSetClientData( void *data )
{
    wxASSERT_MSG( m_clientDataType != wxClientData_Object,
                  wxT("can't have both object and void client data") );

    m_clientData = data;
    m_clientDataType = wxClientData_Void;
}

void *wxEvtHandler::DoGetClientData() const
{
    // it's not an error to call GetClientData() on a window which doesn't have
    // client data at all - nullptr will be returned
    wxASSERT_MSG( m_clientDataType != wxClientData_Object,
                  wxT("this window doesn't have void client data") );

    return m_clientData;
}

// A helper to find an wxEventConnectionRef object
wxEventConnectionRef *
wxEvtHandler::FindRefInTrackerList(wxEvtHandler *eventSink)
{
    for ( wxTrackerNode *node = eventSink->GetFirst(); node; node = node->m_nxt )
    {
        // we only want wxEventConnectionRef nodes here
        wxEventConnectionRef *evtConnRef = node->ToEventConnection();
        if ( evtConnRef && evtConnRef->m_src == this )
        {
            wxASSERT( evtConnRef->m_sink==eventSink );
            return evtConnRef;
        }
    }

    return nullptr;
}

void wxEvtHandler::OnSinkDestroyed( wxEvtHandler *sink )
{
    wxASSERT(m_dynamicEvents);

    // remove all connections with this sink
    size_t cookie;
    for ( wxDynamicEventTableEntry* entry = GetFirstDynamicEntry(cookie);
          entry;
          entry = GetNextDynamicEntry(cookie) )
    {
        if ( entry->m_fn->GetEvtHandler() == sink )
        {
            delete entry->m_callbackUserData;
            delete entry;

            // Just as in DoUnbind(), we use our knowledge of
            // GetNextDynamicEntry() implementation here.
            (*m_dynamicEvents)[cookie] = nullptr;
        }
    }
}

#endif // wxUSE_BASE

#if wxUSE_GUI

// Find a window with the focus, that is also a descendant of the given window.
// This is used to determine the window to initially send commands to.
wxWindow* wxFindFocusDescendant(wxWindow* ancestor)
{
    // Process events starting with the window with the focus, if any.
    wxWindow* focusWin = wxWindow::FindFocus();
    wxWindow* win = focusWin;

    // Check if this is a descendant of this frame.
    // If not, win will be set to nullptr.
    while (win)
    {
        if (win == ancestor)
            break;
        else
            win = win->GetParent();
    }
    if (win == nullptr)
        focusWin = nullptr;

    return focusWin;
}

// ----------------------------------------------------------------------------
// wxEventBlocker
// ----------------------------------------------------------------------------

wxEventBlocker::wxEventBlocker(wxWindow *win, wxEventType type)
{
    wxCHECK_RET(win, wxT("Null window given to wxEventBlocker"));

    m_window = win;

    Block(type);
    m_window->PushEventHandler(this);
}

wxEventBlocker::~wxEventBlocker()
{
    wxEvtHandler *popped = m_window->PopEventHandler(false);
    wxCHECK_RET(popped == this,
        wxT("Don't push other event handlers into a window managed by wxEventBlocker!"));
}

bool wxEventBlocker::ProcessEvent(wxEvent& event)
{
    // should this event be blocked?
    for ( size_t i = 0; i < m_eventsToBlock.size(); i++ )
    {
        wxEventType t = (wxEventType)m_eventsToBlock[i];
        if ( t == wxEVT_ANY || t == event.GetEventType() )
            return true;   // yes, it should: mark this event as processed
    }

    return wxEvtHandler::ProcessEvent(event);
}

#endif // wxUSE_GUI

