From cae6316d3adf36a76fb7c51c6119f98f418d635b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=BDeljan=20Rikalo?= <zeljko@lazarus-ide.org>
Date: Wed, 4 Oct 2023 14:44:36 +0000
Subject: [PATCH] Revert "Qt5, Qt6: removed
 TQtWSCustomTabControl.GetDefaultClientRect since it does not..."

This reverts commit 1d4695e3be66f80e875b989467eb32d91d7d97ac
---
 lcl/interfaces/qt5/qtpagecontrol.inc | 101 +++++++++++++++++++++++++++
 lcl/interfaces/qt5/qtwscomctrls.pp   |   3 +
 lcl/interfaces/qt6/qtpagecontrol.inc | 101 +++++++++++++++++++++++++++
 lcl/interfaces/qt6/qtwscomctrls.pp   |   3 +
 4 files changed, 208 insertions(+)

diff --git a/lcl/interfaces/qt5/qtpagecontrol.inc b/lcl/interfaces/qt5/qtpagecontrol.inc
index 46e1b2580e..87487148c2 100644
--- a/lcl/interfaces/qt5/qtpagecontrol.inc
+++ b/lcl/interfaces/qt5/qtpagecontrol.inc
@@ -185,6 +185,107 @@ begin
   end;
 end;
 
+class function TQtWSCustomTabControl.GetDefaultClientRect(
+  const AWinControl: TWinControl; const aLeft, aTop, aWidth, aHeight: integer;
+  var aClientRect: TRect): boolean;
+var
+  dx, dy: integer;
+  ATabWidget: TQtTabWidget;
+  ASize: TSize;
+  HSpace: Integer;
+  Overlap: Integer;
+  VSpace: Integer;
+  BaseHeight: Integer;
+  TabOverLap: Integer;
+  ShiftVertical: Integer;
+begin
+  Result := False;
+  if AWinControl.HandleAllocated then
+  begin
+    if TQtWidget(AWinControl.Handle).ChildOfComplexWidget <> ccwTTabControl then
+    begin
+      ATabWidget := TQtTabWidget(AWinControl.Handle);
+      if ATabWidget.testAttribute(QtWA_PendingResizeEvent) or not ATabWidget.testAttribute(QtWA_Mapped) then
+      begin
+        // we must recalculate aclientrect since we have pending resize event
+        // and clientrect won't be accurate.issue #21805
+        Result := True;
+        dx := GetPixelMetric(QStylePM_DefaultFrameWidth, nil, ATabWidget.Widget);
+        // HSpace := GetPixelMetric(QStylePM_TabBarTabHSpace, nil, nil);
+        VSpace := GetPixelMetric(QStylePM_TabBarTabVSpace, nil, ATabWidget.Widget);
+        Overlap := GetPixelMetric(QStylePM_TabBarBaseOverlap, nil, ATabWidget.Widget);
+        TabOverLap := GetPixelMetric(QStylePM_TabBarTabOverlap, nil, ATabWidget.Widget);
+        BaseHeight := GetPixelMetric(QStylePM_TabBarBaseHeight, nil, ATabWidget.Widget);
+        ShiftVertical := GetPixelMetric(QStylePM_TabBarTabShiftVertical, nil, ATabWidget.Widget);
+
+        // trigger sizing, do not remove
+        ATabWidget.TabBar.sizeHint(@ASize);
+
+        if ATabWidget.getTabPosition in [QTabWidgetNorth, QTabWidgetSouth] then
+        begin
+          if TCustomTabControl(AWinControl).ShowTabs then
+            dy := ATabWidget.TabBar.getHeight
+          else
+            dy := 0;
+
+          if (BaseHeight < ShiftVertical) then
+          begin
+            if (Overlap = 0) then
+            begin
+              BaseHeight := BaseHeight + TabOverLap;
+              dx := dx + (TabOverlap * 2);
+            end else
+            begin
+              BaseHeight := BaseHeight * 2;
+              dx := dx + BaseHeight;
+            end;
+          end;
+
+          if (Overlap > VSpace) then
+            BaseHeight := BaseHeight * 2;
+
+          if (VSpace > TabOverLap) then
+            dx := dx + Overlap;
+
+          aClientRect := Rect(0, 0,
+               Max(0, aWidth - (BaseHeight * 2)),
+               Max(0, aHeight - dx  - dy));
+        end else
+        begin
+          if TCustomTabControl(AWinControl).ShowTabs then
+            dy := ATabWidget.TabBar.getWidth
+          else
+            dy := 0;
+
+          VSpace := 0;
+          HSpace := 0;
+
+          if BaseHeight < ShiftVertical then
+            VSpace := TabOverLap - BaseHeight;
+          if (Overlap < dx) then
+          begin
+            VSpace := OverLap;
+            if OverLap = 0 then
+            begin
+              VSpace := TabOverLap * 2;
+              HSpace := BaseHeight;
+            end;
+          end;
+
+          aClientRect := Rect(0,0,
+               Max(0, aWidth - dx  - dy - VSpace),
+               Max(0, aHeight - (dx + Overlap + VSpace + HSpace)));
+        end;
+      end;
+    end;
+  end else
+  begin
+    dx := GetPixelMetric(QStylePM_TabBarBaseHeight, nil, nil);
+    aClientRect := Rect(0,0, Max(0, aWidth - (dx * 2)), Max(0, aHeight - (dx * 2)));
+    Result := True;
+  end;
+end;
+
 class procedure TQtWSCustomTabControl.AddPage(const ATabControl: TCustomTabControl;
   const AChild: TCustomPage; const AIndex: integer);
 var
diff --git a/lcl/interfaces/qt5/qtwscomctrls.pp b/lcl/interfaces/qt5/qtwscomctrls.pp
index b35edc2a57..3a0a85569c 100644
--- a/lcl/interfaces/qt5/qtwscomctrls.pp
+++ b/lcl/interfaces/qt5/qtwscomctrls.pp
@@ -53,6 +53,9 @@ type
   published
     class function  CreateHandle(const AWinControl: TWinControl;
           const AParams: TCreateParams): TLCLHandle; override;
+    class function GetDefaultClientRect(const AWinControl: TWinControl;
+             const {%H-}aLeft, {%H-}aTop, aWidth, aHeight: integer; var aClientRect: TRect
+             ): boolean; override;
     class procedure AddPage(const ATabControl: TCustomTabControl;
       const AChild: TCustomPage; const AIndex: integer); override;
     class procedure MovePage(const ATabControl: TCustomTabControl;
diff --git a/lcl/interfaces/qt6/qtpagecontrol.inc b/lcl/interfaces/qt6/qtpagecontrol.inc
index 46e1b2580e..87487148c2 100644
--- a/lcl/interfaces/qt6/qtpagecontrol.inc
+++ b/lcl/interfaces/qt6/qtpagecontrol.inc
@@ -185,6 +185,107 @@ begin
   end;
 end;
 
+class function TQtWSCustomTabControl.GetDefaultClientRect(
+  const AWinControl: TWinControl; const aLeft, aTop, aWidth, aHeight: integer;
+  var aClientRect: TRect): boolean;
+var
+  dx, dy: integer;
+  ATabWidget: TQtTabWidget;
+  ASize: TSize;
+  HSpace: Integer;
+  Overlap: Integer;
+  VSpace: Integer;
+  BaseHeight: Integer;
+  TabOverLap: Integer;
+  ShiftVertical: Integer;
+begin
+  Result := False;
+  if AWinControl.HandleAllocated then
+  begin
+    if TQtWidget(AWinControl.Handle).ChildOfComplexWidget <> ccwTTabControl then
+    begin
+      ATabWidget := TQtTabWidget(AWinControl.Handle);
+      if ATabWidget.testAttribute(QtWA_PendingResizeEvent) or not ATabWidget.testAttribute(QtWA_Mapped) then
+      begin
+        // we must recalculate aclientrect since we have pending resize event
+        // and clientrect won't be accurate.issue #21805
+        Result := True;
+        dx := GetPixelMetric(QStylePM_DefaultFrameWidth, nil, ATabWidget.Widget);
+        // HSpace := GetPixelMetric(QStylePM_TabBarTabHSpace, nil, nil);
+        VSpace := GetPixelMetric(QStylePM_TabBarTabVSpace, nil, ATabWidget.Widget);
+        Overlap := GetPixelMetric(QStylePM_TabBarBaseOverlap, nil, ATabWidget.Widget);
+        TabOverLap := GetPixelMetric(QStylePM_TabBarTabOverlap, nil, ATabWidget.Widget);
+        BaseHeight := GetPixelMetric(QStylePM_TabBarBaseHeight, nil, ATabWidget.Widget);
+        ShiftVertical := GetPixelMetric(QStylePM_TabBarTabShiftVertical, nil, ATabWidget.Widget);
+
+        // trigger sizing, do not remove
+        ATabWidget.TabBar.sizeHint(@ASize);
+
+        if ATabWidget.getTabPosition in [QTabWidgetNorth, QTabWidgetSouth] then
+        begin
+          if TCustomTabControl(AWinControl).ShowTabs then
+            dy := ATabWidget.TabBar.getHeight
+          else
+            dy := 0;
+
+          if (BaseHeight < ShiftVertical) then
+          begin
+            if (Overlap = 0) then
+            begin
+              BaseHeight := BaseHeight + TabOverLap;
+              dx := dx + (TabOverlap * 2);
+            end else
+            begin
+              BaseHeight := BaseHeight * 2;
+              dx := dx + BaseHeight;
+            end;
+          end;
+
+          if (Overlap > VSpace) then
+            BaseHeight := BaseHeight * 2;
+
+          if (VSpace > TabOverLap) then
+            dx := dx + Overlap;
+
+          aClientRect := Rect(0, 0,
+               Max(0, aWidth - (BaseHeight * 2)),
+               Max(0, aHeight - dx  - dy));
+        end else
+        begin
+          if TCustomTabControl(AWinControl).ShowTabs then
+            dy := ATabWidget.TabBar.getWidth
+          else
+            dy := 0;
+
+          VSpace := 0;
+          HSpace := 0;
+
+          if BaseHeight < ShiftVertical then
+            VSpace := TabOverLap - BaseHeight;
+          if (Overlap < dx) then
+          begin
+            VSpace := OverLap;
+            if OverLap = 0 then
+            begin
+              VSpace := TabOverLap * 2;
+              HSpace := BaseHeight;
+            end;
+          end;
+
+          aClientRect := Rect(0,0,
+               Max(0, aWidth - dx  - dy - VSpace),
+               Max(0, aHeight - (dx + Overlap + VSpace + HSpace)));
+        end;
+      end;
+    end;
+  end else
+  begin
+    dx := GetPixelMetric(QStylePM_TabBarBaseHeight, nil, nil);
+    aClientRect := Rect(0,0, Max(0, aWidth - (dx * 2)), Max(0, aHeight - (dx * 2)));
+    Result := True;
+  end;
+end;
+
 class procedure TQtWSCustomTabControl.AddPage(const ATabControl: TCustomTabControl;
   const AChild: TCustomPage; const AIndex: integer);
 var
diff --git a/lcl/interfaces/qt6/qtwscomctrls.pp b/lcl/interfaces/qt6/qtwscomctrls.pp
index 5d4a9dee0e..c5db8532d4 100644
--- a/lcl/interfaces/qt6/qtwscomctrls.pp
+++ b/lcl/interfaces/qt6/qtwscomctrls.pp
@@ -51,6 +51,9 @@ type
   published
     class function  CreateHandle(const AWinControl: TWinControl;
           const AParams: TCreateParams): TLCLHandle; override;
+    class function GetDefaultClientRect(const AWinControl: TWinControl;
+             const {%H-}aLeft, {%H-}aTop, aWidth, aHeight: integer; var aClientRect: TRect
+             ): boolean; override;
     class procedure AddPage(const ATabControl: TCustomTabControl;
       const AChild: TCustomPage; const AIndex: integer); override;
     class procedure MovePage(const ATabControl: TCustomTabControl;