[PTRun] Drag and drop files (#22409)

* [PTRun] Support drag&drop to other application for files in result list

* [PTRun] use file/folder thumbnail as drag image

* (fix spellcheck)

* [PTRun] use _mouseDownResultViewModel.Image to generate the drag image

* fix spelling + refactoring

src/modules/launcher/PowerLauncher/Helper/DragDataObject.cs

@@ -0,0 +1,99 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+namespace PowerLauncher.Helper
+{
+    using System;
+    using System.Drawing;
+    using System.Runtime.InteropServices;
+    using System.Runtime.InteropServices.ComTypes;
+    using DrawingImaging = System.Drawing.Imaging;
+    using MediaImaging = System.Windows.Media.Imaging;
+
+    // based on: https://stackoverflow.com/questions/61041282/showing-image-thumbnail-with-mouse-cursor-while-dragging/61148788#61148788
+    public static class DragDataObject
+    {
+        private static readonly Guid DataObject = new Guid("b8c0bd9f-ed24-455c-83e6-d5390c4fe8c4");
+
+        public static IDataObject FromFile(string filePath)
+        {
+            Marshal.ThrowExceptionForHR(SHCreateItemFromParsingName(filePath, null, typeof(IShellItem).GUID, out IShellItem item));
+            Marshal.ThrowExceptionForHR(item.BindToHandler(null, DataObject, typeof(IDataObject).GUID, out object dataObject));
+            return (IDataObject)dataObject;
+        }
+
+        public static void SetDragImage(this IDataObject dataObject, IntPtr hBitmap, int width, int height)
+        {
+            if (dataObject == null)
+            {
+                throw new ArgumentNullException(nameof(dataObject));
+            }
+
+            IDragSourceHelper dragDropHelper = (IDragSourceHelper)new DragDropHelper();
+            ShDragImage dragImage = new ShDragImage
+            {
+                HBmpDragImage = hBitmap,
+                SizeDragImage = new Size(width, height),
+            };
+            Marshal.ThrowExceptionForHR(dragDropHelper.InitializeFromBitmap(ref dragImage, dataObject));
+        }
+
+        [DllImport("shell32", CharSet = CharSet.Unicode)]
+        private static extern int SHCreateItemFromParsingName(string path, IBindCtx pbc, [MarshalAs(UnmanagedType.LPStruct)] Guid riid, out IShellItem ppv);
+
+        [Guid("43826d1e-e718-42ee-bc55-a1e261c37bfe")]
+        [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
+        private interface IShellItem
+        {
+            [PreserveSig]
+            int BindToHandler(IBindCtx pbc, [MarshalAs(UnmanagedType.LPStruct)] Guid bhid, [MarshalAs(UnmanagedType.LPStruct)] Guid riid, [MarshalAs(UnmanagedType.IUnknown)] out object ppv);
+
+            // more methods available, but we don't need them
+        }
+
+        [ComImport]
+        [Guid("4657278a-411b-11d2-839a-00c04fd918d0")] // CLSID_DragDropHelper
+        private class DragDropHelper
+        {
+        }
+
+        // https://docs.microsoft.com/en-us/windows/win32/api/shobjidl_core/ns-shobjidl_core-shdragimage
+        [StructLayout(LayoutKind.Sequential)]
+        private struct ShDragImage
+        {
+            public Size SizeDragImage;
+            public Point PtOffset;
+            public IntPtr HBmpDragImage;
+            public int CrColorKey;
+        }
+
+        // https://docs.microsoft.com/en-us/windows/win32/api/shobjidl_core/nn-shobjidl_core-idragsourcehelper
+        [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
+        [Guid("DE5BF786-477A-11D2-839D-00C04FD918D0")]
+        private interface IDragSourceHelper
+        {
+            [PreserveSig]
+            int InitializeFromBitmap(ref ShDragImage pShDrawImage, IDataObject pDataObject);
+
+            // more methods available, but we don't need them
+        }
+
+        // https://stackoverflow.com/a/2897325
+        public static Bitmap BitmapSourceToBitmap(MediaImaging.BitmapSource source)
+        {
+            if (source == null)
+            {
+                return null;
+            }
+
+            Bitmap bitmap = new Bitmap(source.PixelWidth, source.PixelHeight, DrawingImaging.PixelFormat.Format32bppArgb);
+            DrawingImaging.BitmapData bitmapData = bitmap.LockBits(new Rectangle(Point.Empty, bitmap.Size), DrawingImaging.ImageLockMode.WriteOnly, DrawingImaging.PixelFormat.Format32bppArgb);
+
+            source.CopyPixels(System.Windows.Int32Rect.Empty, bitmapData.Scan0, bitmapData.Height * bitmapData.Stride, bitmapData.Stride);
+            bitmap.UnlockBits(bitmapData);
+
+            return bitmap;
+        }
+    }
+}

src/modules/launcher/PowerLauncher/MainWindow.xaml.cs

@@ -4,6 +4,7 @@
 
 using System;
 using System.ComponentModel;
+using System.IO;
 using System.Linq;
 using System.Reactive.Linq;
 using System.Runtime.InteropServices;
@@ -12,6 +13,7 @@ using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Input;
 using System.Windows.Interop;
+using System.Windows.Media.Imaging;
 using Common.UI;
 using interop;
 using Microsoft.PowerLauncher.Telemetry;
@@ -21,7 +23,10 @@ using PowerLauncher.Plugin;
 using PowerLauncher.Telemetry.Events;
 using PowerLauncher.ViewModel;
 using Wox.Infrastructure.UserSettings;
+using Wox.Plugin;
+using Wox.Plugin.Interfaces;
 using CancellationToken = System.Threading.CancellationToken;
+using Image = Wox.Infrastructure.Image;
 using KeyEventArgs = System.Windows.Input.KeyEventArgs;
 using Log = Wox.Plugin.Logger.Log;
 using Screen = System.Windows.Forms.Screen;
@@ -40,6 +45,8 @@ namespace PowerLauncher
         private bool _coldStateHotkeyPressed;
         private bool _disposedValue;
         private IDisposable _reactiveSubscription;
+        private Point _mouseDownPosition;
+        private ResultViewModel _mouseDownResultViewModel;
 
         public MainWindow(PowerToysRunSettings settings, MainViewModel mainVM, CancellationToken nativeWaiterCancelToken)
             : this()
@@ -191,6 +198,8 @@ namespace PowerLauncher
             ListBox.DataContext = _viewModel;
             ListBox.SuggestionsList.SelectionChanged += SuggestionsList_SelectionChanged;
             ListBox.SuggestionsList.PreviewMouseLeftButtonUp += SuggestionsList_PreviewMouseLeftButtonUp;
+            ListBox.SuggestionsList.PreviewMouseLeftButtonDown += SuggestionsList_PreviewMouseLeftButtonDown;
+            ListBox.SuggestionsList.MouseMove += SuggestionsList_MouseMove;
             _viewModel.PropertyChanged += ViewModel_PropertyChanged;
             _viewModel.MainWindowVisibility = Visibility.Collapsed;
             _viewModel.LoadedAtLeastOnce = true;
@@ -282,6 +291,48 @@ namespace PowerLauncher
             }
         }
 
+        private void SuggestionsList_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
+        {
+            _mouseDownPosition = e.GetPosition(null);
+            _mouseDownResultViewModel = ((FrameworkElement)e.OriginalSource).DataContext as ResultViewModel;
+        }
+
+        private void SuggestionsList_MouseMove(object sender, MouseEventArgs e)
+        {
+            if (e.LeftButton == MouseButtonState.Pressed && _mouseDownResultViewModel?.Result?.ContextData is IFileDropResult fileDropResult)
+            {
+                Vector dragDistance = _mouseDownPosition - e.GetPosition(null);
+                if (Math.Abs(dragDistance.X) > SystemParameters.MinimumHorizontalDragDistance || Math.Abs(dragDistance.Y) > SystemParameters.MinimumVerticalDragDistance)
+                {
+                    _viewModel.Hide();
+
+                    try
+                    {
+                        // DoDragDrop with file thumbnail as drag image
+                        var dataObject = DragDataObject.FromFile(fileDropResult.Path);
+                        using var bitmap = DragDataObject.BitmapSourceToBitmap((BitmapSource)_mouseDownResultViewModel?.Image);
+                        IntPtr hBitmap = bitmap.GetHbitmap();
+
+                        try
+                        {
+                            dataObject.SetDragImage(hBitmap, Constant.ThumbnailSize, Constant.ThumbnailSize);
+                            DragDrop.DoDragDrop(ListBox.SuggestionsList, dataObject, DragDropEffects.Copy);
+                        }
+                        finally
+                        {
+                            Image.NativeMethods.DeleteObject(hBitmap);
+                        }
+                    }
+                    catch
+                    {
+                        // DoDragDrop without drag image
+                        IDataObject dataObject = new DataObject(DataFormats.FileDrop, new[] { fileDropResult.Path });
+                        DragDrop.DoDragDrop(ListBox.SuggestionsList, dataObject, DragDropEffects.Copy);
+                    }
+                }
+            }
+        }
+
         private void ViewModel_PropertyChanged(object sender, PropertyChangedEventArgs e)
         {
             if (e.PropertyName == nameof(MainViewModel.MainWindowVisibility))