Migrated the DibHelper to the DibFileFormatHandler

src/Greenshot.Base/Core/ClipboardHelper.cs

@@ -867,11 +867,17 @@ EndSelection:<<<<<<<4
                     {
                         // Create the stream for the clipboard
                         dibStream = new MemoryStream();
-                        var dibBytes = ((Bitmap)imageToSave).ConvertToDib();
-                        dibStream.Write(dibBytes,0, dibBytes.Length);
 
-                        // Set the DIB to the clipboard DataObject
-                        dataObject.SetData(DataFormats.Dib, false, dibStream);
+                        if (!FileFormatHandlerRegistry.TrySaveToStream((Bitmap)imageToSave, dibStream, DataFormats.Dib))
+                        {
+                            dibStream.Dispose();
+                            dibStream = null;
+                        }
+                        else
+                        {
+                            // Set the DIB to the clipboard DataObject
+                            dataObject.SetData(DataFormats.Dib, false, dibStream);
+                        }
                     }
                 }
                 catch (Exception dibEx)

src/Greenshot.Base/Core/FileFormatHandlers/DefaultFileFormatHandler.cs

@@ -31,7 +31,7 @@ using Greenshot.Base.Interfaces.Drawing;
 namespace Greenshot.Base.Core.FileFormatHandlers
 {
     /// <summary>
-    /// THis is the default .NET bitmap file format handler
+    /// This is the default .NET bitmap file format handler
     /// </summary>
     public class DefaultFileFormatHandler : IFileFormatHandler
     {
@@ -56,7 +56,7 @@ namespace Greenshot.Base.Core.FileFormatHandlers
                 return false;
             }
 
-            return OurExtensions.Contains(extension);
+            return OurExtensions.Contains(extension?.ToLowerInvariant());
         }
 
         /// <inheritdoc />

src/Greenshot.Base/Core/FileFormatHandlers/DibFileFormatHandler.cs

@@ -1,48 +1,100 @@
 /*
  * Greenshot - a free and open source screenshot tool
  * Copyright (C) 2007-2021 Thomas Braun, Jens Klingen, Robin Krom
- *
+ * 
  * For more information see: https://getgreenshot.org/
  * The Greenshot project is hosted on GitHub https://github.com/greenshot/greenshot
- *
+ * 
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, either version 1 of the License, or
  * (at your option) any later version.
- *
+ * 
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
- *
+ * 
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
 using System;
+using System.Collections.Generic;
 using System.Drawing;
 using System.Drawing.Imaging;
+using System.IO;
+using System.Linq;
 using System.Runtime.InteropServices;
+using Greenshot.Base.Interfaces;
+using Greenshot.Base.Interfaces.Drawing;
 using Greenshot.Base.UnmanagedHelpers;
 
-namespace Greenshot.Base.Core
+namespace Greenshot.Base.Core.FileFormatHandlers
 {
     /// <summary>
-    /// Though Greenshot implements the specs for the DIB image format,
-    /// it seems to cause a lot of issues when using the clipboard.
-    /// There is some research done about the DIB on the clipboard, this code is based upon the information 
-    /// <a href="https://stackoverflow.com/questions/44177115/copying-from-and-to-clipboard-loses-image-transparency">here</a>
+    /// This handles creating a DIB (Device Independent Bitmap) on the clipboard
     /// </summary>
-    internal static class DibHelper
+    public class DibFileFormatHandler : IFileFormatHandler
     {
         private const double DpiToPelsPerMeter = 39.3701;
+        private static readonly string [] OurExtensions = { "dib" };
+
+        /// <inheritdoc />
+        public IEnumerable<string> SupportedExtensions(FileFormatHandlerActions fileFormatHandlerAction)
+        {
+            if (fileFormatHandlerAction == FileFormatHandlerActions.LoadDrawableFromStream)
+            {
+                return Enumerable.Empty<string>();
+            }
+
+            return OurExtensions;
+        }
+
+        /// <inheritdoc />
+        public bool Supports(FileFormatHandlerActions fileFormatHandlerAction, string extension)
+        {
+            if (string.IsNullOrEmpty(extension) || fileFormatHandlerAction != FileFormatHandlerActions.SaveToStream)
+            {
+                return false;
+            }
+            
+            return OurExtensions.Contains(extension.ToLowerInvariant());
+        }
+
+        /// <inheritdoc />
+        public int PriorityFor(FileFormatHandlerActions fileFormatHandlerAction, string extension)
+        {
+            return int.MaxValue;
+        }
+
+        /// <inheritdoc />
+        public bool TrySaveToStream(Bitmap bitmap, Stream destination, string extension)
+        {
+            var dibBytes = ConvertToDib(bitmap);
+            destination.Write(dibBytes, 0, dibBytes.Length);
+            return true;
+        }
+
+        /// <inheritdoc />
+        public bool TryLoadFromStream(Stream stream, string extension, out Bitmap bitmap)
+        {
+            throw new NotImplementedException();
+        }
+
+        /// <inheritdoc />
+        public bool TryLoadDrawableFromStream(Stream stream, string extension, out IDrawableContainer drawableContainer, ISurface surface)
+        {
+            throw new NotImplementedException();
+        }
+
 
         /// <summary>
         /// Converts the Bitmap to a Device Independent Bitmap format of type BITFIELDS.
         /// </summary>
         /// <param name="sourceBitmap">Bitmap to convert to DIB</param>
         /// <returns>byte{} with the image converted to DIB</returns>
-        public static byte[] ConvertToDib(this Bitmap sourceBitmap)
+        private static byte[] ConvertToDib(Bitmap sourceBitmap)
         {
             if (sourceBitmap == null) throw new ArgumentNullException(nameof(sourceBitmap));
 

src/Greenshot.Base/Core/FileFormatHandlers/FileFormatHandlerRegistry.cs

@@ -20,6 +20,8 @@
  */
 
 using System.Collections.Generic;
+using System.Drawing;
+using System.IO;
 using System.Linq;
 using Greenshot.Base.Interfaces;
 
@@ -27,7 +29,7 @@ namespace Greenshot.Base.Core.FileFormatHandlers
 {
     public static class FileFormatHandlerRegistry
     {
-        public static readonly IList<IFileFormatHandler> FileFormatHandlers = new List<IFileFormatHandler>();
+        public static IList<IFileFormatHandler> FileFormatHandlers { get; } = new List<IFileFormatHandler>();
 
         static FileFormatHandlerRegistry()
         {
@@ -40,5 +42,29 @@ namespace Greenshot.Base.Core.FileFormatHandlers
         {
             return FileFormatHandlers.SelectMany(ffh => ffh.SupportedExtensions(fileFormatHandlerAction)).Distinct();
         }
+
+        /// <summary>
+        /// This wrapper method for TrySaveToStream will do:
+        /// Find all the IFileFormatHandler which support the action for the supplied extension.
+        /// Take the first, to call the TrySaveToStream on.
+        /// </summary>
+        /// <param name="bitmap">Bitmap</param>
+        /// <param name="destination">Stream</param>
+        /// <param name="extension">string</param>
+        /// <returns>bool</returns>
+        public static bool TrySaveToStream(Bitmap bitmap, Stream destination, string extension)
+        {
+            var fileFormatHandler = FileFormatHandlers
+                .Where(ffh => ffh.Supports(FileFormatHandlerActions.LoadFromStream, extension))
+                .OrderBy(ffh => ffh.PriorityFor(FileFormatHandlerActions.LoadFromStream, extension))
+                .FirstOrDefault();
+
+            if (fileFormatHandler == null)
+            {
+                return false;
+            }
+
+            return fileFormatHandler.TrySaveToStream(bitmap, destination, extension);
+        }
     }
 }

src/Greenshot.Base/Core/FileFormatHandlers/GreenshotFileFormatHandler.cs

@@ -52,7 +52,7 @@ namespace Greenshot.Base.Core.FileFormatHandlers
                 return false;
             }
 
-            return OurExtensions.Contains(extension);
+            return OurExtensions.Contains(extension?.ToLowerInvariant());
         }
 
 

src/Greenshot.Base/Core/FileFormatHandlers/IconFileFormatHandler.cs

@@ -59,7 +59,7 @@ namespace Greenshot.Base.Core.FileFormatHandlers
                 return false;
             }
 
-            return OurExtensions.Contains(extension);
+            return OurExtensions.Contains(extension?.ToLowerInvariant());
         }
 
         /// <inheritdoc />

src/Greenshot.Base/Core/FileFormatHandlers/PngFileFormatHandler.cs

@@ -55,7 +55,7 @@ namespace Greenshot.Base.Core.FileFormatHandlers
                 return false;
             }
 
-            return OurExtensions.Contains(extension);
+            return OurExtensions.Contains(extension?.ToLowerInvariant());
         }
         /// <inheritdoc />
         public int PriorityFor(FileFormatHandlerActions fileFormatHandlerAction, string extension)