From f268580a280a3237efa6942c0a3be6ac1e1d5654 Mon Sep 17 00:00:00 2001
From: Robert Di Pardo <59004801+rdipardo@users.noreply.github.com>
Date: Wed, 6 Mar 2024 19:38:16 -0500
Subject: [PATCH 1/2] Remove `WS_EX_CONTROLPARENT` when the panel undocks

Fixes #83
---
 CSVLintNppPlugin/CsvLintNppPlugin.csproj      |  3 +
 CSVLintNppPlugin/Forms/CsvLintWindow.cs       |  2 +-
 CSVLintNppPlugin/Forms/DockingFormBase.cs     | 67 +++++++++++++++++++
 .../PluginInfrastructure/Win32.cs             | 61 +++++++++++++++++
 4 files changed, 132 insertions(+), 1 deletion(-)
 create mode 100644 CSVLintNppPlugin/Forms/DockingFormBase.cs

diff --git a/CSVLintNppPlugin/CsvLintNppPlugin.csproj b/CSVLintNppPlugin/CsvLintNppPlugin.csproj
index 36bdf98..0b31e78 100644
--- a/CSVLintNppPlugin/CsvLintNppPlugin.csproj
+++ b/CSVLintNppPlugin/CsvLintNppPlugin.csproj
@@ -140,6 +140,9 @@
     <Compile Include="Forms\CsvLintWindow.Designer.cs">
       <DependentUpon>CsvLintWindow.cs</DependentUpon>
     </Compile>
+    <Compile Include="Forms\DockingFormBase.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
     <Compile Include="PluginInfrastructure\ScintillaStreams.cs" />
     <Compile Include="PluginInfrastructure\Win32.cs" />
     <Compile Include="Main.cs" />
diff --git a/CSVLintNppPlugin/Forms/CsvLintWindow.cs b/CSVLintNppPlugin/Forms/CsvLintWindow.cs
index 75e7afb..3771462 100644
--- a/CSVLintNppPlugin/Forms/CsvLintWindow.cs
+++ b/CSVLintNppPlugin/Forms/CsvLintWindow.cs
@@ -9,7 +9,7 @@
 
 namespace Kbg.NppPluginNET
 {
-    public partial class CsvLintWindow : Form
+    public partial class CsvLintWindow : DockingFormBase
     {
         public CsvLintWindow()
         {
diff --git a/CSVLintNppPlugin/Forms/DockingFormBase.cs b/CSVLintNppPlugin/Forms/DockingFormBase.cs
new file mode 100644
index 0000000..85ad606
--- /dev/null
+++ b/CSVLintNppPlugin/Forms/DockingFormBase.cs
@@ -0,0 +1,67 @@
+using System;
+using System.Runtime.InteropServices;
+using System.Windows.Forms;
+using Kbg.NppPluginNET.PluginInfrastructure;
+
+namespace CSVLintNppPlugin.Forms
+{
+    public partial class DockingFormBase : UserControl
+    {
+        private static Win32.WindowLongGetter _wndLongGetter;
+        private static Win32.WindowLongSetter _wndLongSetter;
+
+        public DockingFormBase()
+        {
+            if (Marshal.SizeOf(typeof(IntPtr)) == 8) // we are 64-bit
+            {
+                _wndLongGetter = Win32.GetWindowLongPtr;
+                _wndLongSetter = Win32.SetWindowLongPtr;
+            }
+            else // we are 32-bit
+            {
+                _wndLongGetter = Win32.GetWindowLong;
+                _wndLongSetter = Win32.SetWindowLong;
+            }
+        }
+
+        protected override void WndProc(ref Message m)
+        {
+            switch (m.Msg)
+            {
+                case Win32.WM_NOTIFY:
+                    var nmdr = (Win32.TagNMHDR)Marshal.PtrToStructure(m.LParam, typeof(Win32.TagNMHDR));
+                    if (nmdr.hwndFrom == PluginBase.nppData._nppHandle)
+                    {
+                        switch ((DockMgrMsg)(nmdr.code & 0xFFFFU))
+                        {
+                            case DockMgrMsg.DMN_DOCK:   // we are being docked
+                                break;
+                            case DockMgrMsg.DMN_FLOAT:  // we are being _un_docked
+                                RemoveControlParent(this);
+                                break;
+                            case DockMgrMsg.DMN_CLOSE:  // we are being closed
+                                break;
+                        }
+                    }
+                    break;
+            }
+            base.WndProc(ref m);
+        }
+
+        private void RemoveControlParent(Control parent)
+        {
+            if (parent.HasChildren)
+            {
+                long extAttrs = (long)_wndLongGetter(parent.Handle, Win32.GWL_EXSTYLE);
+                if (Win32.WS_EX_CONTROLPARENT == (extAttrs & Win32.WS_EX_CONTROLPARENT))
+                {
+                    _wndLongSetter(parent.Handle, Win32.GWL_EXSTYLE, new IntPtr(extAttrs & ~Win32.WS_EX_CONTROLPARENT));
+                }
+                foreach (Control c in parent.Controls)
+                {
+                    RemoveControlParent(c);
+                }
+            }
+        }
+    }
+}
diff --git a/CSVLintNppPlugin/PluginInfrastructure/Win32.cs b/CSVLintNppPlugin/PluginInfrastructure/Win32.cs
index 3933e00..53dd4ca 100644
--- a/CSVLintNppPlugin/PluginInfrastructure/Win32.cs
+++ b/CSVLintNppPlugin/PluginInfrastructure/Win32.cs
@@ -48,6 +48,17 @@ public struct ScrollInfo
             public int nTrackPos;
         }
 
+        /// <summary>
+        /// @see https://learn.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-nmhdr
+        /// </summary>
+        [StructLayout(LayoutKind.Sequential)]
+        public struct TagNMHDR
+        {
+            public IntPtr hwndFrom;
+            public UIntPtr idFrom;
+            public uint code;
+        }
+
         /// <summary>
         /// Used for the ScrollInfo fMask
         /// SIF_ALL             => Combination of SIF_PAGE, SIF_POS, SIF_RANGE, and SIF_TRACKPOS.
@@ -302,6 +313,56 @@ public static IntPtr SendMessage(IntPtr hWnd, uint Msg, int wParam, ref LangType
         public static extern int CheckMenuItem(IntPtr hmenu, int uIDCheckItem, int uCheck);
 
         public const int WM_CREATE = 1;
+        public const int WM_NOTIFY = 0x004e;
+        public const int GWL_EXSTYLE = -20;
+        public const int GWLP_HINSTANCE = -6;
+        public const int GWLP_HWNDPARENT = -8;
+        public const int GWLP_ID = -12;
+        public const int GWL_STYLE = -16;
+        public const int GWLP_USERDATA = -21;
+        public const int GWLP_WNDPROC = -4;
+        public const long WS_EX_ACCEPTFILES = 0x00000010L;
+        public const long WS_EX_APPWINDOW = 0x00040000L;
+        public const long WS_EX_CLIENTEDGE = 0x00000200L;
+        public const long WS_EX_COMPOSITED = 0x02000000L;
+        public const long WS_EX_CONTEXTHELP = 0x00000400L;
+        public const long WS_EX_CONTROLPARENT = 0x00010000L;
+        public const long WS_EX_DLGMODALFRAME = 0x00000001L;
+        public const long WS_EX_LAYERED = 0x00080000L;
+        public const long WS_EX_LAYOUTRTL = 0x00400000L;
+        public const long WS_EX_LEFT = 0x00000000L;
+        public const long WS_EX_LEFTSCROLLBAR = 0x00004000L;
+        public const long WS_EX_LTRREADING = 0x00000000L;
+        public const long WS_EX_MDICHILD = 0x00000040L;
+        public const long WS_EX_NOACTIVATE = 0x08000000L;
+        public const long WS_EX_NOINHERITLAYOUT = 0x00100000L;
+        public const long WS_EX_NOPARENTNOTIFY = 0x00000004L;
+        public const long WS_EX_NOREDIRECTIONBITMAP = 0x00200000L;
+        public const long WS_EX_OVERLAPPEDWINDOW = (WS_EX_WINDOWEDGE | WS_EX_CLIENTEDGE);
+        public const long WS_EX_PALETTEWINDOW = (WS_EX_WINDOWEDGE | WS_EX_TOOLWINDOW | WS_EX_TOPMOST);
+        public const long WS_EX_RIGHT = 0x00001000L;
+        public const long WS_EX_RIGHTSCROLLBAR = 0x00000000L;
+        public const long WS_EX_RTLREADING = 0x00002000L;
+        public const long WS_EX_STATICEDGE = 0x00020000L;
+        public const long WS_EX_TOOLWINDOW = 0x00000080L;
+        public const long WS_EX_TOPMOST = 0x00000008L;
+        public const long WS_EX_TRANSPARENT = 0x00000020L;
+        public const long WS_EX_WINDOWEDGE = 0x00000100L;
+
+        public delegate IntPtr WindowLongGetter(IntPtr hWnd, int nIndex);
+        public delegate IntPtr WindowLongSetter(IntPtr hWnd, int nIndex, IntPtr dwNewLong);
+
+        [DllImport("user32")]
+        public static extern IntPtr GetWindowLongPtr(IntPtr hWnd, int nIndex);
+
+        [DllImport("user32")]
+        public static extern IntPtr GetWindowLong(IntPtr hWnd, int nIndex);
+
+        [DllImport("user32")]
+        public static extern IntPtr SetWindowLongPtr(IntPtr hWnd, int nIndex, IntPtr dwNewLong);
+
+        [DllImport("user32")]
+        public static extern IntPtr SetWindowLong(IntPtr hWnd, int nIndex, IntPtr dwNewLong);
 
         [DllImport("user32")]
         public static extern bool ClientToScreen(IntPtr hWnd, ref Point lpPoint);

From 175a187828edfeafc014baf09f4d08e6cd981fcb Mon Sep 17 00:00:00 2001
From: Robert Di Pardo <59004801+rdipardo@users.noreply.github.com>
Date: Wed, 6 Mar 2024 23:10:31 -0500
Subject: [PATCH 2/2] Derive from `Form` to keep dark mode theming consistent

---
 CSVLintNppPlugin/CsvLintNppPlugin.csproj      |  5 ++-
 .../Forms/DockingFormBase.Designer.cs         | 37 +++++++++++++++++++
 CSVLintNppPlugin/Forms/DockingFormBase.cs     |  3 +-
 3 files changed, 43 insertions(+), 2 deletions(-)
 create mode 100644 CSVLintNppPlugin/Forms/DockingFormBase.Designer.cs

diff --git a/CSVLintNppPlugin/CsvLintNppPlugin.csproj b/CSVLintNppPlugin/CsvLintNppPlugin.csproj
index 0b31e78..878ad45 100644
--- a/CSVLintNppPlugin/CsvLintNppPlugin.csproj
+++ b/CSVLintNppPlugin/CsvLintNppPlugin.csproj
@@ -141,7 +141,10 @@
       <DependentUpon>CsvLintWindow.cs</DependentUpon>
     </Compile>
     <Compile Include="Forms\DockingFormBase.cs">
-      <SubType>UserControl</SubType>
+      <SubType>Form</SubType>
+    </Compile>
+    <Compile Include="Forms\DockingFormBase.Designer.cs">
+      <DependentUpon>DockingFormBase.cs</DependentUpon>
     </Compile>
     <Compile Include="PluginInfrastructure\ScintillaStreams.cs" />
     <Compile Include="PluginInfrastructure\Win32.cs" />
diff --git a/CSVLintNppPlugin/Forms/DockingFormBase.Designer.cs b/CSVLintNppPlugin/Forms/DockingFormBase.Designer.cs
new file mode 100644
index 0000000..0a69c75
--- /dev/null
+++ b/CSVLintNppPlugin/Forms/DockingFormBase.Designer.cs
@@ -0,0 +1,37 @@
+namespace CSVLintNppPlugin.Forms
+{
+    partial class DockingFormBase
+    {
+        /// <summary> 
+        /// Required designer variable.
+        /// </summary>
+        private System.ComponentModel.IContainer components = null;
+
+        /// <summary> 
+        /// Clean up any resources being used.
+        /// </summary>
+        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+        protected override void Dispose(bool disposing)
+        {
+            if (disposing && (components != null))
+            {
+                components.Dispose();
+            }
+            base.Dispose(disposing);
+        }
+
+        #region Component Designer generated code
+
+        /// <summary> 
+        /// Required method for Designer support - do not modify 
+        /// the contents of this method with the code editor.
+        /// </summary>
+        private void InitializeComponent()
+        {
+            components = new System.ComponentModel.Container();
+            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
+        }
+
+        #endregion
+    }
+}
diff --git a/CSVLintNppPlugin/Forms/DockingFormBase.cs b/CSVLintNppPlugin/Forms/DockingFormBase.cs
index 85ad606..ee7c31b 100644
--- a/CSVLintNppPlugin/Forms/DockingFormBase.cs
+++ b/CSVLintNppPlugin/Forms/DockingFormBase.cs
@@ -5,13 +5,14 @@
 
 namespace CSVLintNppPlugin.Forms
 {
-    public partial class DockingFormBase : UserControl
+    public partial class DockingFormBase : Form
     {
         private static Win32.WindowLongGetter _wndLongGetter;
         private static Win32.WindowLongSetter _wndLongSetter;
 
         public DockingFormBase()
         {
+            InitializeComponent();
             if (Marshal.SizeOf(typeof(IntPtr)) == 8) // we are 64-bit
             {
                 _wndLongGetter = Win32.GetWindowLongPtr;