{ $Id$}
{
 *****************************************************************************
 *                            Win32WSControls.pp                             *
 *                            ------------------                             *
 *                                                                           *
 *                                                                           *
 *****************************************************************************

 *****************************************************************************
  This file is part of the Lazarus Component Library (LCL)

  See the file COPYING.modifiedLGPL.txt, included in this distribution,
  for details about the license.
 *****************************************************************************
}
unit Win32WSControls;

{$mode objfpc}{$H+}
{$I win32defines.inc}

interface

uses
////////////////////////////////////////////////////
// I M P O R T A N T
////////////////////////////////////////////////////
// To get as little as posible circles,
// uncomment only when needed for registration
////////////////////////////////////////////////////
  CommCtrl, Windows, Classes, Controls, Graphics,
////////////////////////////////////////////////////
  WSControls, WSLCLClasses, SysUtils, Win32Proc, Win32Extra, WSProc,
  { LCL }
  InterfaceBase, LCLType, LCLIntf, LCLProc, LazUTF8, Themes, Forms;

type
  { TWin32WSDragImageListResolution }

  TWin32WSDragImageListResolution = class(TWSDragImageListResolution)
  published
    class function BeginDrag(const ADragImageList: TDragImageListResolution; Window: HWND;
      AIndex, X, Y: Integer): Boolean; override;
    class function DragMove(const ADragImageList: TDragImageListResolution; X, Y: Integer): Boolean; override;
    class procedure EndDrag(const ADragImageList: TDragImageListResolution); override;
    class function HideDragImage(const ADragImageList: TDragImageListResolution;
      ALockedWindow: HWND; DoUnLock: Boolean): Boolean; override;
    class function ShowDragImage(const ADragImageList: TDragImageListResolution;
      ALockedWindow: HWND; X, Y: Integer; DoLock: Boolean): Boolean; override;
  end;

  { TWin32WSControl }

  TWin32WSControl = class(TWSControl)
  published
  end;

  { TWin32WSWinControl }

  TWin32WSWinControl = class(TWSWinControl)
  published
    class procedure AddControl(const AControl: TControl); override;

    class function  GetText(const AWinControl: TWinControl; var AText: String): Boolean; override;
    class procedure SetBiDiMode(const AWinControl: TWinControl; UseRightToLeftAlign, UseRightToLeftReading, UseRightToLeftScrollBar : Boolean); override;
    class procedure SetBounds(const AWinControl: TWinControl; const ALeft, ATop, AWidth, AHeight: Integer); override;
    class procedure SetBorderStyle(const AWinControl: TWinControl; const ABorderStyle: TBorderStyle); override;
    class procedure SetChildZPosition(const AWinControl, AChild: TWinControl;
                                      const AOldPos, ANewPos: Integer;
                                      const AChildren: TFPList); override;
    class procedure SetColor(const AWinControl: TWinControl); override;
    class procedure SetFont(const AWinControl: TWinControl; const AFont: TFont); override;
    class procedure SetText(const AWinControl: TWinControl; const AText: string); override;
    class procedure SetCursor(const AWinControl: TWinControl; const ACursor: HCursor); override;
    class procedure SetShape(const AWinControl: TWinControl; const AShape: HBITMAP); override;

    class procedure ConstraintsChange(const AWinControl: TWinControl); override;
    class function  CreateHandle(const AWinControl: TWinControl;
          const AParams: TCreateParams): HWND; override;
    class procedure DestroyHandle(const AWinControl: TWinControl); override;
    class procedure Invalidate(const AWinControl: TWinControl); override;
    class procedure PaintTo(const AWinControl: TWinControl; ADC: HDC; X, Y: Integer); override;
    class procedure ShowHide(const AWinControl: TWinControl); override;
    class procedure ScrollBy(const AWinControl: TWinControl; DeltaX, DeltaY: integer); override;
  end;

  { TWin32WSGraphicControl }

  TWin32WSGraphicControl = class(TWSGraphicControl)
  published
  end;

  { TWin32WSCustomControl }

  TWin32WSCustomControl = class(TWSCustomControl)
  published
  end;

  { TWin32WSImageList }

  TWin32WSImageList = class(TWSImageList)
  published
  end;

type
  TCreateWindowExParams = record
    Buddy, Parent, Window: HWND;
    Left, Top, Height, Width: integer;
    WindowInfo, BuddyWindowInfo: PWin32WindowInfo;
    Flags, FlagsEx: dword;
    SubClassWndProc: pointer;
    StrCaption, WindowTitle: String;
    pClassName: PChar;
    pSubClassName: PChar;
  end;

  TNCCreateParams = record
    WinControl: TWinControl;
    DefWndProc: WNDPROC;
    Handled: Boolean;
  end;
  PNCCreateParams = ^TNCCreateParams;


// TODO: better names?

procedure PrepareCreateWindow(const AWinControl: TWinControl;
  const CreateParams: TCreateParams; out Params: TCreateWindowExParams);
procedure FinishCreateWindow(const AWinControl: TWinControl; var Params: TCreateWindowExParams;
  const AlternateCreateWindow: boolean; SubClass: Boolean = False);
procedure WindowCreateInitBuddy(const AWinControl: TWinControl;
  var Params: TCreateWindowExParams);
  
// Must be in win32proc but TCreateWindowExParams declared here
procedure SetStdBiDiModeParams(const AWinControl: TWinControl; var Params:TCreateWindowExParams);

var
  // WindowPosChanging hack - see comment in TWin32WSWinControl.SetBounds
  LockWindowPosChanging: Boolean = False;
  LockWindowPosChangingXY: TPoint;

implementation

uses
  Win32Int;

{ Global helper routines }

procedure PrepareCreateWindow(const AWinControl: TWinControl;
  const CreateParams: TCreateParams; out Params: TCreateWindowExParams);
begin
  with Params do
  begin
    Window := HWND(nil);
    Buddy := HWND(nil);
    WindowTitle := '';
    SubClassWndProc := @WindowProc;

    Flags := CreateParams.Style;
    FlagsEx := CreateParams.ExStyle;
    Parent := CreateParams.WndParent;
    StrCaption := CreateParams.Caption;

    Left := CreateParams.X;
    Top := CreateParams.Y;
    Width := CreateParams.Width;
    Height := CreateParams.Height;

    LCLBoundsToWin32Bounds(AWinControl, Left, Top);
    SetStdBiDiModeParams(AWinControl, Params);

    if not (csDesigning in AWinControl.ComponentState) and not AWinControl.IsEnabled then
      Flags := Flags or WS_DISABLED;

    {$IFDEF VerboseSizeMsg}
    DebugLn('PrepareCreateWindow ' + dbgsName(AWinControl) + ' ' +
      Format('%d, %d, %d, %d', [Left, Top, Width, Height]));
    {$ENDIF}
  end;
end;

procedure FinishCreateWindow(const AWinControl: TWinControl; var Params: TCreateWindowExParams;
  const AlternateCreateWindow: boolean; SubClass: Boolean = False);
var
  lhFont: HFONT;
  AErrorCode: Cardinal;
  NCCreateParams: TNCCreateParams;
  WindowClassW, DummyClassW: WndClassW;
begin
  NCCreateParams.DefWndProc := nil;
  NCCreateParams.WinControl := AWinControl;
  NCCreateParams.Handled := False;

  if not AlternateCreateWindow then
  begin
    with Params do
    begin
      if SubClass then
      begin
        if GetClassInfoW(System.HInstance, PWideChar(WideString(pClassName)),
                         LPWNDCLASSW(@WindowClassW)) then
        begin
          NCCreateParams.DefWndProc := WndProc(WindowClassW.lpfnWndProc);
          if not GetClassInfoW(System.HInstance, PWideChar(WideString(pSubClassName)),
                               LPWNDCLASSW(@DummyClassW)) then
          begin
            with WindowClassW do
            begin
              LPFnWndProc := SubClassWndProc;
              hInstance := System.HInstance;
              lpszClassName := PWideChar(WideString(pSubClassName));
            end;
            Windows.RegisterClassW(LPWNDCLASSW(@WindowClassW));
          end;
          pClassName := pSubClassName;
        end;
      end;

      Window := CreateWindowExW(FlagsEx, PWideChar(WideString(pClassName)),
        PWideChar(UTF8ToUTF16(WindowTitle)), Flags,
        Left, Top, Width, Height, Parent, 0, HInstance, @NCCreateParams);

      if Window = 0 then
      begin
        AErrorCode := GetLastError;
        DebugLn(['Failed to create win32 control, error: ', AErrorCode, ' : ', GetLastErrorText(AErrorCode)]);
        raise Exception.Create('Failed to create win32 control, error: ' + IntToStr(AErrorCode) + ' : ' + GetLastErrorText(AErrorCode));
      end;
    end;
    { after creating a child window the following happens:
      1) the previously bottom window is thrown to the top
      2) the created window is added at the bottom
      undo this by throwing them both to the bottom again }
    { not needed anymore, tab order is handled entirely by LCL now
    Windows.SetWindowPos(Windows.GetTopWindow(Parent), HWND_BOTTOM, 0, 0, 0, 0, SWP_NOMOVE or SWP_NOSIZE);
    Windows.SetWindowPos(Window, HWND_BOTTOM, 0, 0, 0, 0, SWP_NOMOVE or SWP_NOSIZE);
    }
  end;

  with Params do
  begin
    if Window <> 0 then
    begin
      // some controls (combobox) immediately send a message upon setting font
      if not NCCreateParams.Handled then
      begin
        WindowInfo := AllocWindowInfo(Window);
        WindowInfo^.needParentPaint := GetWin32WindowInfo(Parent)^.needParentPaint;
        WindowInfo^.WinControl := AWinControl;
        AWinControl.Handle := Window;
        if Assigned(SubClassWndProc) then
          WindowInfo^.DefWndProc := Windows.WNDPROC(SetWindowLongPtrW(
            Window, GWL_WNDPROC, PtrInt(SubClassWndProc)));
        // Set control ID to map WinControl. This is required for messages that sent to parent
        // to extract control from the passed ID.
        // In case of subclassing this ID will be set in WM_NCCREATE message handler
        // Important: do not store the object pointer here because GWL_ID can take only 32bit values
        //   Windows Handles are always 32bit (also on 64bit system) so it is safe to store the Handle and find the WinControl from the Handle then
        //   We set the WinControl property here in case InitializeWnd is too late
        SetProp(Window, 'WinControl', WindowInfo^.WinControl);
        SetWindowLongPtrW(Window, GWL_ID, PtrInt(Window));
      end;

      if AWinControl.Font.IsDefault then
        lhFont := Win32WidgetSet.DefaultFont
      else
        lhFont := AWinControl.Font.Reference.Handle;
      Windows.SendMessage(Window, WM_SETFONT, WPARAM(lhFont), 0);
    end;
  end;
end;

procedure WindowCreateInitBuddy(const AWinControl: TWinControl;
  var Params: TCreateWindowExParams);
var
  lhFont: HFONT;
begin
  with Params do
    if Buddy <> HWND(Nil) then
    begin
      BuddyWindowInfo := AllocWindowInfo(Buddy);
      BuddyWindowInfo^.AWinControl := AWinControl;
      BuddyWindowInfo^.DefWndProc := Windows.WNDPROC(SetWindowLongPtrW(
        Buddy, GWL_WNDPROC, PtrInt(SubClassWndProc)));
      if AWinControl.Font.IsDefault then
        lhFont := Win32Widgetset.DefaultFont
      else
        lhFont := AWinControl.Font.Reference.Handle;
      Windows.SendMessage(Buddy, WM_SETFONT, WPARAM(lhFont), 0);
    end
    else
      BuddyWindowInfo := nil;
end;

procedure SetStdBiDiModeParams(const AWinControl: TWinControl; var Params:TCreateWindowExParams);
begin
  with Params do
  begin
    //remove old bidimode ExFlags
    FlagsEx := FlagsEx and not(WS_EX_RTLREADING or WS_EX_RIGHT or WS_EX_LEFTSCROLLBAR);

    if AWinControl.UseRightToLeftAlignment then
      FlagsEx := FlagsEx or WS_EX_RIGHT;
    if AWinControl.UseRightToLeftScrollBar then
      FlagsEx := FlagsEx or WS_EX_LEFTSCROLLBAR;
    if AWinControl.UseRightToLeftReading then
      FlagsEx := FlagsEx or WS_EX_RTLREADING;
  end;
end;

{ TWin32WSWinControl }

class function TWin32WSWinControl.CreateHandle(const AWinControl: TWinControl;
  const AParams: TCreateParams): HWND;
var
  Params: TCreateWindowExParams;
begin
  // general initialization of Params
  PrepareCreateWindow(AWinControl, AParams, Params);
  // customization of Params
  with Params do
  begin
    pClassName := @ClsName[0];
    SubClassWndProc := nil;
  end;
  // create window
  FinishCreateWindow(AWinControl, Params, false);
  Result := Params.Window;
end;

class procedure TWin32WSWinControl.AddControl(const AControl: TControl);
var
  ParentHandle, ChildHandle: HWND;
begin
  {$ifdef OldToolbar}
  if (AControl.Parent is TToolbar) then
    exit;
  {$endif}

  with TWinControl(AControl) do
  begin
    ParentHandle := Parent.Handle;
    ChildHandle := Handle;
  end;

  Windows.SetParent(ChildHandle, ParentHandle);
end;

class function  TWin32WSWinControl.GetText(const AWinControl: TWinControl; var AText: String): Boolean;
begin
  AText := '';
  Result := false;
end;

class procedure TWin32WSWinControl.SetBiDiMode(const AWinControl : TWinControl;
  UseRightToLeftAlign, UseRightToLeftReading, UseRightToLeftScrollBar : Boolean
  );
var
  FlagsEx: dword;
begin
  if not WSCheckHandleAllocated(AWinControl, 'SetBiDiMode') then
    Exit;

  FlagsEx := GetWindowLong(AWinControl.Handle, GWL_EXSTYLE);
  FlagsEx := FlagsEx and not (WS_EX_RTLREADING or WS_EX_RIGHT or WS_EX_LEFTSCROLLBAR);
  if UseRightToLeftAlign then
    FlagsEx := FlagsEx or WS_EX_RIGHT;
  if UseRightToLeftReading then
    FlagsEx := FlagsEx or WS_EX_RTLREADING ;
  if UseRightToLeftScrollBar then
    FlagsEx := FlagsEx or WS_EX_LEFTSCROLLBAR;
  SetWindowLongPtrW(AWinControl.Handle, GWL_EXSTYLE, FlagsEx);
end;

class procedure TWin32WSWinControl.SetBorderStyle(const AWinControl: TWinControl; const ABorderStyle: TBorderStyle);
begin
  RecreateWnd(AWinControl);
  if AWinControl.HandleObjectShouldBeVisible then
    AWinControl.HandleNeeded;
end;

class procedure TWin32WSWinControl.SetChildZPosition(
  const AWinControl, AChild: TWinControl; const AOldPos, ANewPos: Integer;
  const AChildren: TFPList);
var
  AfterWnd: hWnd;
  n, StopPos: Integer;
  Child: TWinControl;
  WindowInfo: PWin32WindowInfo;
begin
  if not WSCheckHandleAllocated(AWincontrol, 'SetChildZPosition')
  then Exit;
  if not WSCheckHandleAllocated(AChild, 'SetChildZPosition (child)')
  then Exit;

  if ANewPos = 0 // bottom
  then AfterWnd := HWND_BOTTOM
  else if ANewPos >= AChildren.Count - 1
  then AfterWnd := HWND_TOP
  else begin
    // Search for the first child above us with a handle
    // the child list is reversed form the windows order.
    // So the first window is the top window and is the last child
    // if we don't find a allocated handle then we are effectively not moved
    AfterWnd := 0;
    if AOldPos > ANewPos
    then StopPos := AOldPos              // The child is moved to the bottom, oldpos is on top of it
    else StopPos := AChildren.Count - 1; // the child is moved to the top

    for n := ANewPos + 1 to StopPos do
    begin
      Child := TWinControl(AChildren[n]);
      if Child.HandleAllocated
      then begin
        AfterWnd := Child.Handle;
        Break;
      end;
    end;

    if AfterWnd = 0 then Exit; // nothing to do
  end;

  WindowInfo := GetWin32WindowInfo(AChild.Handle);
  if WindowInfo^.UpDown <> 0 then
  begin
    Windows.SetWindowPos(WindowInfo^.UpDown, AfterWnd, 0, 0, 0, 0,
      SWP_NOACTIVATE or SWP_NOMOVE or SWP_NOOWNERZORDER or
      SWP_NOSIZE or SWP_NOSENDCHANGING or SWP_DEFERERASE);
    Windows.SetWindowPos(AChild.Handle, WindowInfo^.UpDown, 0, 0, 0, 0,
      SWP_NOACTIVATE or SWP_NOMOVE or SWP_NOOWNERZORDER or
      SWP_NOSIZE or SWP_NOSENDCHANGING or SWP_DEFERERASE);
  end
  else
    Windows.SetWindowPos(AChild.Handle, AfterWnd, 0, 0, 0, 0,
      SWP_NOACTIVATE or SWP_NOMOVE or SWP_NOOWNERZORDER or
      SWP_NOSIZE or SWP_NOSENDCHANGING or SWP_DEFERERASE);
end;

{------------------------------------------------------------------------------
  Method:  SetBounds
  Params:  AWinControl                  - the object which invoked this function
           ALeft, ATop, AWidth, AHeight - new dimensions for the control
  Pre:     AWinControl.HandleAllocated
  Returns: Nothing

  Resize a window
 ------------------------------------------------------------------------------}
class procedure TWin32WSWinControl.SetBounds(const AWinControl: TWinControl;
  const ALeft, ATop, AWidth, AHeight: Integer);
var
  IntfLeft, IntfTop, IntfWidth, IntfHeight: integer;
  suppressMove: boolean;
  Handle: HWND;
  WindowPlacement: TWINDOWPLACEMENT;
  Mon: HMONITOR;
  MonInfo: TMonitorInfo;
begin
  IntfLeft := ALeft;
  IntfTop := ATop;
  IntfWidth := AWidth;
  IntfHeight := AHeight;
  LCLBoundsToWin32Bounds(AWinControl, IntfLeft, IntfTop);
  {$IFDEF VerboseSizeMsg}
  DebugLn('TWin32WSWinControl.ResizeWindow A ', dbgsName(AWinControl),
    ' LCL=',Format('%d, %d, %d, %d', [ALeft,ATop,AWidth,AHeight]),
    ' Win32=',Format('%d, %d, %d, %d', [IntfLeft,IntfTop,IntfWidth,IntfHeight])
    );
  {$ENDIF}
  suppressMove := False;
  AdaptBounds(AWinControl, IntfLeft, IntfTop, IntfWidth, IntfHeight, suppressMove);
  if not suppressMove then
  begin
    Handle := AWinControl.Handle;
    WindowPlacement.length := SizeOf(WindowPlacement);

    // Windows (at least Win 10) has the feature that SetWindowPos() forces dialogs with parent windows on the same screen
    //   with the parent window - the position set with Windows.SetWindowPos() is ignored and instead the dialog
    //   is centered with its parent window.
    // To prevent Windows from changing the position defined by the LCL, the LM_WINDOWPOSCHANGING is handled and the
    //   new coordinates are re-assigned within the message handler with LockWindowPosChanging&LockWindowPosChangingXY
    // See issue #39479 for more description and demo application.
    LockWindowPosChanging := True;
    try
      LockWindowPosChangingXY := Point(IntfLeft, IntfTop);
      if IsIconic(Handle) and GetWindowPlacement(Handle, @WindowPlacement) then
      begin
        WindowPlacement.rcNormalPosition := Bounds(IntfLeft, IntfTop, IntfWidth, IntfHeight);
        // workarea coordinates must be used for top-level windows without WS_EX_TOOLWINDOW window style
        if (GetWindowLong(Handle, GWL_EXSTYLE) and WS_EX_TOOLWINDOW)=0 then
        begin
          Mon := MonitorFromRect(@WindowPlacement.rcNormalPosition, MONITOR_DEFAULTTOPRIMARY);
          MonInfo := Default(TMonitorInfo);
          MonInfo.cbSize := SizeOf(TMonitorInfo);
          if (Mon<>0) and GetMonitorInfo(Mon, @MonInfo) then
            WindowPlacement.rcNormalPosition.Offset(MonInfo.rcMonitor.Left-MonInfo.rcWork.Left, MonInfo.rcMonitor.Top-MonInfo.rcWork.Top);
        end;
        SetWindowPlacement(Handle, @WindowPlacement);
      end
      else
        Windows.SetWindowPos(Handle, 0, IntfLeft, IntfTop, IntfWidth, IntfHeight, SWP_NOZORDER or SWP_NOACTIVATE);
    finally
      LockWindowPosChanging := False;
    end;
  end;
  LCLControlSizeNeedsUpdate(AWinControl, True);
  // If this control is a child of an MDI form, then we need to update the MDI client bounds in
  // case this control has affected the client area
  if Assigned(Application.MainForm) and (AWinControl.Parent=Application.MainForm) and (Application.MainForm.FormStyle=fsMDIForm) then
    Win32WidgetSet.UpdateMDIClientBounds;
end;

class procedure TWin32WSWinControl.SetColor(const AWinControl: TWinControl);
begin
  // TODO: to be implemented, had no implementation in LM_SETCOLOR message
end;

class procedure TWin32WSWinControl.SetFont(const AWinControl: TWinControl; const AFont: TFont);
begin
  if not WSCheckHandleAllocated(AWinControl, 'SetFont')
  then Exit;
  Windows.SendMessage(AWinControl.Handle, WM_SETFONT, Windows.WParam(AFont.Reference.Handle), 1);
end;

class procedure TWin32WSWinControl.SetText(const AWinControl: TWinControl; const AText: string);
begin
  if not WSCheckHandleAllocated(AWincontrol, 'SetText') then Exit;
  SendMessageW(AWinControl.Handle, WM_SETTEXT, 0, LPARAM(PWideChar(UTF8ToUTF16(AText))));
end;

class procedure TWin32WSWinControl.SetCursor(const AWinControl: TWinControl; const ACursor: HCursor);
var
  CursorPos, P: TPoint;
  h: HWND;
  HitTestCode: LResult;
begin
  // in win32 controls have no cursor property. they can change their cursor
  // by listening WM_SETCURSOR and adjusting global cursor
  if csDesigning in AWinControl.ComponentState then
  begin
    Windows.SetCursor(ACursor);
    Exit;
  end;

  if Screen.RealCursor <> crDefault then exit;

  Windows.GetCursorPos(CursorPos);

  h := AWinControl.Handle;
  P := CursorPos;
  Windows.ScreenToClient(h, @P);
  h := Windows.ChildWindowFromPointEx(h, Windows.POINT(P), CWP_SKIPINVISIBLE or CWP_SKIPDISABLED);

  HitTestCode := SendMessage(h, WM_NCHITTEST, 0, LParam((CursorPos.X and $FFFF) or (CursorPos.Y shl 16)));
  SendMessage(h, WM_SETCURSOR, WParam(h), Windows.MAKELONG(HitTestCode, WM_MOUSEMOVE));
end;

class procedure TWin32WSWinControl.SetShape(const AWinControl: TWinControl;
  const AShape: HBITMAP);
var
  Rgn: HRGN;
begin
  if not WSCheckHandleAllocated(AWinControl, 'SetShape') then
    Exit;

  if AShape <> 0 then
    Rgn := BitmapToRegion(AShape)
  else
    Rgn := 0;
  Windows.SetWindowRgn(AWinControl.Handle, Rgn, True);
  if Rgn <> 0 then
    DeleteObject(Rgn);
end;

class procedure TWin32WSWinControl.ConstraintsChange(const AWinControl: TWinControl);
begin
  // TODO: implement me!
end;

class procedure TWin32WSWinControl.DestroyHandle(const AWinControl: TWinControl);
var
  Handle: HWND;
begin
  Handle := AWinControl.Handle;
  {$ifdef RedirectDestroyMessages}
  SetWindowLongPtrW(Handle, GWL_WNDPROC, PtrInt(@DestroyWindowProc));
  {$endif}
  // Instead of calling DestroyWindow directly, we need to call WM_MDIDESTROY for MDI children
  if Assigned(Application.MainForm) and (Application.MainForm.FormStyle=fsMDIForm) and
    (AWinControl is TCustomForm) and (TCustomForm(AWinControl).FormStyle=fsMDIChild) then
    SendMessage(Win32WidgetSet.MDIClientHandle, WM_MDIDESTROY, Handle, 0)
  else
    DestroyWindow(Handle);
end;

class procedure TWin32WSWinControl.Invalidate(const AWinControl: TWinControl);
begin
  // lpRect = nil updates entire client area of window
  InvalidateRect(AWinControl.Handle, nil, True);
end;

class procedure TWin32WSWinControl.PaintTo(const AWinControl: TWinControl;
  ADC: HDC; X, Y: Integer);
var
  SavedDC: Integer;
begin
  SavedDC := SaveDC(ADC);
  MoveWindowOrgEx(ADC, X, Y);
  SendMessage(AWinControl.Handle, WM_PRINT, WParam(ADC),
    PRF_CHECKVISIBLE or PRF_CHILDREN or PRF_CLIENT or PRF_NONCLIENT or PRF_OWNED);
  RestoreDC(ADC, SavedDC);
end;

class procedure TWin32WSWinControl.ShowHide(const AWinControl: TWinControl);
const
  VisibilityToFlag: array[Boolean] of UINT = (SWP_HIDEWINDOW, SWP_SHOWWINDOW);
begin
  Windows.SetWindowPos(AWinControl.Handle, 0, 0, 0, 0, 0,
    SWP_NOSIZE or SWP_NOMOVE or SWP_NOZORDER or SWP_NOACTIVATE or VisibilityToFlag[AWinControl.HandleObjectShouldBeVisible]);
  // If this control is a child of an MDI form, then we need to update the MDI client bounds in
  // case altering this control's visibility has affected the client area
  if Assigned(Application.MainForm) and (AWinControl.Parent=Application.MainForm) and (Application.MainForm.FormStyle=fsMDIForm) then
    Win32WidgetSet.UpdateMDIClientBounds;
end;

class procedure TWin32WSWinControl.ScrollBy(const AWinControl: TWinControl;
  DeltaX, DeltaY: integer);
begin
  if AWinControl.HandleAllocated then
    ScrollWindowEx(AWinControl.Handle, DeltaX, DeltaY, nil, nil, 0, nil,
      SW_INVALIDATE or SW_ERASE or SW_SCROLLCHILDREN);
end;

{ TWin32WSDragImageListResolution }

class function TWin32WSDragImageListResolution.BeginDrag(
  const ADragImageList: TDragImageListResolution; Window: HWND; AIndex, X,
  Y: Integer): Boolean;
begin
  // No check to Handle should be done, because if there is no handle (no needed)
  // we must create it here. This is normal for imagelist (we can never need handle)
  Result := ImageList_BeginDrag(ADragImageList.Reference.Handle, AIndex, X, Y);
end;

class function TWin32WSDragImageListResolution.DragMove(const ADragImageList: TDragImageListResolution;
  X, Y: Integer): Boolean;
begin
  Result := ImageList_DragMove(X, Y);
end;

class procedure TWin32WSDragImageListResolution.EndDrag(const ADragImageList: TDragImageListResolution);
begin
  ImageList_EndDrag;
end;

class function TWin32WSDragImageListResolution.HideDragImage(const ADragImageList: TDragImageListResolution;
  ALockedWindow: HWND; DoUnLock: Boolean): Boolean;
begin
  if DoUnLock then
    Result := ImageList_DragLeave(ALockedWindow)
  else
    Result := ImageList_DragShowNolock(False);
end;

class function TWin32WSDragImageListResolution.ShowDragImage(const ADragImageList: TDragImageListResolution;
  ALockedWindow: HWND; X, Y: Integer; DoLock: Boolean): Boolean;
begin
  if DoLock then
    Result := ImageList_DragEnter(ALockedWindow, X, Y)
  else
    Result := ImageList_DragShowNolock(True);
end;

end.