Refactor snap to edge

(cherry picked from commit 9295c343b3797d469e393a4cd2cc771c80fff7ea)

src/Greenshot.Base/Interfaces/Drawing/IDrawableContainer.cs

@@ -29,6 +29,14 @@ using Greenshot.Base.Interfaces.Drawing.Adorners;
 
 namespace Greenshot.Base.Interfaces.Drawing
 {
+    public enum Direction
+    {
+        LEFT,
+        RIGHT,
+        TOP,
+        BOTTOM,
+    }
+
     public interface IDrawableContainer : INotifyPropertyChanged, IDisposable
     {
         /// <summary>
@@ -111,5 +119,12 @@ namespace Greenshot.Base.Interfaces.Drawing
         /// <param name="surface">ISurface</param>
         /// <param name="mouseEventArgs">MouseEventArgs</param>
         void AddContextMenuItems(ContextMenuStrip menu, ISurface surface, MouseEventArgs mouseEventArgs);
+
+        /// <summary>
+        /// Snap the container to the edge of the surface.
+        /// </summary>
+        /// <param name="direction">Direction in which to move the container.</param>
+        /// <param name="surface">The surface the container belongs to.</param>
+        void SnapToEdge(Direction direction, ISurface surface);
     }
 }

src/Greenshot.Editor/Drawing/DrawableContainer.cs

@@ -684,5 +684,43 @@ namespace Greenshot.Editor.Drawing
         protected virtual void InitializeFields()
         {
         }
+
+        /// <summary>
+        /// Snap the container to the edge of the surface.
+        /// </summary>
+        /// <param name="direction">Direction in which to move the container.</param>
+        /// <param name="surface">The surface the container belongs to.</param>
+        public void SnapToEdge(Direction direction, ISurface surface)
+        {
+            Size surfaceBounds = new(surface.Image.Width, surface.Image.Height);
+            NativeRectFloat newBounds = GetLocationAfterSnap(direction, this.Bounds, surfaceBounds);
+
+            this.MakeBoundsChangeUndoable(allowMerge: false);
+            this.ApplyBounds(newBounds);
+        }
+
+        private static NativeRectFloat GetLocationAfterSnap(Direction direction, NativeRect bounds, Size surfaceSize)
+        {
+            switch (direction)
+            {
+                case Direction.LEFT:
+                    bounds = bounds.ChangeX(0);
+                    break;
+                case Direction.RIGHT:
+                    bounds = bounds.Offset(offsetX: surfaceSize.Width - bounds.Right);
+                    break;
+                case Direction.TOP:
+                    bounds = bounds.ChangeY(0);
+                    break;
+                case Direction.BOTTOM:
+                    bounds = bounds.Offset(offsetY: surfaceSize.Height - bounds.Bottom);
+                    break;
+                default:
+                    break;
+            }
+            return bounds;
+        }
+
+
     }
 }

src/Greenshot.Editor/Drawing/DrawableContainerList.cs

@@ -39,14 +39,6 @@ using Greenshot.Editor.Memento;
 
 namespace Greenshot.Editor.Drawing
 {
-    public enum Direction
-    {
-        LEFT,
-        RIGHT,
-        TOP,
-        BOTTOM,
-    }
-
     /// <summary>
     /// Dispatches most of a DrawableContainer's public properties and methods to a list of DrawableContainers.
     /// </summary>
@@ -743,7 +735,7 @@ namespace Greenshot.Editor.Drawing
                     MakeBoundsChangeUndoable(false);
                     item.Width = surface.Image.Width;
                 }
-                SnapAllToEdge(Direction.LEFT, surface, this);
+                SnapAllToEdge(Direction.LEFT, surface);
                 surface.Invalidate(); // not sure if this belongs
             };
             fitSubmenu.DropDownItems.Add(item);
@@ -760,7 +752,7 @@ namespace Greenshot.Editor.Drawing
                     MakeBoundsChangeUndoable(false);
                     item.Height = surface.Image.Height;
                 }
-                SnapAllToEdge(Direction.TOP, surface, this);
+                SnapAllToEdge(Direction.TOP, surface);
                 surface.Invalidate(); // not sure if this belongs
             };
             fitSubmenu.DropDownItems.Add(item);
@@ -775,7 +767,7 @@ namespace Greenshot.Editor.Drawing
             };
             item.Click += delegate
             {
-                SnapAllToEdge(Direction.LEFT, surface, this);
+                SnapAllToEdge(Direction.LEFT, surface);
             };
             snapSubmenu.DropDownItems.Add(item);
 
@@ -786,7 +778,7 @@ namespace Greenshot.Editor.Drawing
             };
             item.Click += delegate
             {
-                SnapAllToEdge(Direction.RIGHT, surface, this);
+                SnapAllToEdge(Direction.RIGHT, surface);
             };
             snapSubmenu.DropDownItems.Add(item);
 
@@ -797,7 +789,7 @@ namespace Greenshot.Editor.Drawing
             };
             item.Click += delegate
             {
-                SnapAllToEdge(Direction.TOP, surface, this);
+                SnapAllToEdge(Direction.TOP, surface);
             };
             snapSubmenu.DropDownItems.Add(item);
 
@@ -808,7 +800,7 @@ namespace Greenshot.Editor.Drawing
             };
             item.Click += delegate
             {
-                SnapAllToEdge(Direction.BOTTOM, surface, this);
+                SnapAllToEdge(Direction.BOTTOM, surface);
             };
             snapSubmenu.DropDownItems.Add(item);
             menu.Items.Add(snapSubmenu);
@@ -922,54 +914,17 @@ namespace Greenshot.Editor.Drawing
             }
         }
 
-        /// <summary>
-        /// Move an element to one edge of the surface.
-        /// </summary>
-        /// <param name="direction">Direction to move the element.</param>
-        /// <param name="surface"></param>
-        /// <param name="targetElement"></param>
-        public void SnapToEdge(Direction direction, ISurface surface, IDrawableContainer targetElement)
-        {
-            Size surfaceBounds = new(surface.Image.Width, surface.Image.Height);
-            NativeRectFloat newBounds = SnapHelper(direction, targetElement.Bounds, surfaceBounds);
-
-            targetElement.MakeBoundsChangeUndoable(allowMerge: false);
-            targetElement.ApplyBounds(newBounds);
-        }
-
-        public static NativeRectFloat SnapHelper(Direction direction, NativeRect bounds, Size surfaceSize)
-        {
-            switch (direction)
-            {
-                case Direction.LEFT:
-                    bounds = bounds.ChangeX(0);
-                    break;
-                case Direction.RIGHT:
-                    bounds = bounds.Offset(offsetX: surfaceSize.Width - bounds.Right);
-                    break;
-                case Direction.TOP:
-                    bounds = bounds.ChangeY(0);
-                    break;
-                case Direction.BOTTOM:
-                    bounds = bounds.Offset(offsetY: surfaceSize.Height - bounds.Bottom);
-                    break;
-                default:
-                    break;
-            }
-            return bounds;
-        }
-
         /// <summary>
         /// Moves all selected elements to one edge of the surface.
         /// </summary>
         /// <param name="direction"></param>
         /// <param name="surface"></param>
-        /// <param name="elements"></param>
+        /// 
-        public void SnapAllToEdge(Direction direction, ISurface surface, IDrawableContainerList elements)
+        public void SnapAllToEdge(Direction direction, ISurface surface)
         {
-            foreach (var item in elements)
+            foreach (IDrawableContainer item in this)
             {
-                SnapToEdge(direction, surface, item);
+                item.SnapToEdge(direction, surface);
             }
             surface.DeselectAllElements();
         }
@@ -986,12 +941,12 @@ namespace Greenshot.Editor.Drawing
             
             surface.ResizeCanvas(expansion.Left, expansion.Right, expansion.Top, expansion.Bottom);
 
-            SnapToEdge(direction, surface, targetElement);
+            targetElement.SnapToEdge(direction, surface);
 
             if (direction == Direction.LEFT || direction == Direction.RIGHT)
-                SnapToEdge(Direction.TOP, surface, targetElement);
+                targetElement.SnapToEdge(Direction.TOP, surface);
             else if (direction == Direction.TOP || direction == Direction.BOTTOM)
-                SnapToEdge(Direction.LEFT, surface, targetElement);
+                targetElement.SnapToEdge(Direction.LEFT, surface);
 
             surface.DeselectAllElements();
         }