push, snap, and fit

(cherry picked from commit dd643c0191faff44b4c04651717859994ad8ef4a)

src/Greenshot.Editor/Drawing/DrawableContainerList.cs

@@ -39,6 +39,14 @@ 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>
@@ -672,6 +680,139 @@ namespace Greenshot.Editor.Drawing
             };
             menu.Items.Add(item);
 
+            // Push out
+            ToolStripMenuItem alignSubmenu = new ToolStripMenuItem("Push Out");
+
+            // Right
+            item = new ToolStripMenuItem("Right")
+            {
+                Image = (Image)EditorFormResources.GetObject("copyToolStripMenuItem.Image")
+            };
+            item.Click += delegate
+            {
+                PushOut(Direction.RIGHT, surface, this[0]);
+            };
+            alignSubmenu.DropDownItems.Add(item);
+
+            // Left
+            item = new ToolStripMenuItem("Left")
+            {
+                Image = (Image)EditorFormResources.GetObject("copyToolStripMenuItem.Image")
+            };
+            item.Click += delegate
+            {
+                PushOut(Direction.LEFT, surface, this[0]);
+            };
+            alignSubmenu.DropDownItems.Add(item);
+
+            // Top
+            item = new ToolStripMenuItem("Top")
+            {
+                Image = (Image)EditorFormResources.GetObject("copyToolStripMenuItem.Image")
+            };
+            item.Click += delegate
+            {
+                PushOut(Direction.TOP, surface, this[0]);
+            };
+            alignSubmenu.DropDownItems.Add(item);
+
+            // Bottom
+            item = new ToolStripMenuItem("Bottom")
+            {
+                Image = (Image)EditorFormResources.GetObject("copyToolStripMenuItem.Image")
+            };
+            item.Click += delegate
+            {
+                PushOut(Direction.BOTTOM, surface, this[0]);
+            };
+            alignSubmenu.DropDownItems.Add(item);
+            menu.Items.Add(alignSubmenu);
+
+            // Fit menu
+            ToolStripMenuItem fitSubmenu = new ToolStripMenuItem("Fit");
+
+            // Fit width
+            item = new ToolStripMenuItem("Fit to width")
+            {
+                Image = (Image)EditorFormResources.GetObject("copyToolStripMenuItem.Image")
+            };
+            item.Click += delegate
+            {
+                foreach (var item in this)
+                {
+                    MakeBoundsChangeUndoable(false);
+                    item.Width = surface.Image.Width;
+                }
+                SnapAllToEdge(Direction.LEFT, surface, this);
+                surface.Invalidate(); // not sure if this belongs
+            };
+            fitSubmenu.DropDownItems.Add(item);
+
+            // Fit height
+            item = new ToolStripMenuItem("Fit to height")
+            {
+                Image = (Image)EditorFormResources.GetObject("copyToolStripMenuItem.Image")
+            };
+            item.Click += delegate
+            {
+                foreach (var item in this)
+                {
+                    MakeBoundsChangeUndoable(false);
+                    item.Height = surface.Image.Height;
+                }
+                SnapAllToEdge(Direction.TOP, surface, this);
+                surface.Invalidate(); // not sure if this belongs
+            };
+            fitSubmenu.DropDownItems.Add(item);
+            menu.Items.Add(fitSubmenu);
+
+            ToolStripMenuItem snapSubmenu = new ToolStripMenuItem("Snap");
+
+            // Snap left
+            item = new ToolStripMenuItem("Snap left")
+            {
+                Image = (Image)EditorFormResources.GetObject("copyToolStripMenuItem.Image")
+            };
+            item.Click += delegate
+            {
+                SnapAllToEdge(Direction.LEFT, surface, this);
+            };
+            snapSubmenu.DropDownItems.Add(item);
+
+            // Snap right
+            item = new ToolStripMenuItem("Snap right")
+            {
+                Image = (Image)EditorFormResources.GetObject("copyToolStripMenuItem.Image")
+            };
+            item.Click += delegate
+            {
+                SnapAllToEdge(Direction.RIGHT, surface, this);
+            };
+            snapSubmenu.DropDownItems.Add(item);
+
+            // Snap to top
+            item = new ToolStripMenuItem("Snap to top")
+            {
+                Image = (Image)EditorFormResources.GetObject("copyToolStripMenuItem.Image")
+            };
+            item.Click += delegate
+            {
+                SnapAllToEdge(Direction.TOP, surface, this);
+            };
+            snapSubmenu.DropDownItems.Add(item);
+
+            // Snap to bottom
+            item = new ToolStripMenuItem("Snap to bottom")
+            {
+                Image = (Image)EditorFormResources.GetObject("copyToolStripMenuItem.Image")
+            };
+            item.Click += delegate
+            {
+                SnapAllToEdge(Direction.BOTTOM, surface, this);
+            };
+            snapSubmenu.DropDownItems.Add(item);
+            menu.Items.Add(snapSubmenu);
+
             // Delete
             item = new ToolStripMenuItem(Language.GetString(LangKey.editor_deleteelement))
             {
@@ -780,5 +921,72 @@ namespace Greenshot.Editor.Drawing
                 drawableContainer.AdjustToDpi(dpi);
             }
         }
+
+        /// <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)
+        {
+            int xMovement = 0, yMovement = 0;
+
+            if (direction == Direction.LEFT)
+                xMovement = -targetElement.Location.X;
+            else if (direction == Direction.RIGHT)
+                xMovement = surface.Image.Width - targetElement.Location.X - targetElement.Width;
+            else if (direction == Direction.TOP)
+                yMovement = -targetElement.Location.Y;
+            else if (direction == Direction.BOTTOM)
+                yMovement = surface.Image.Height - targetElement.Location.Y - targetElement.Height;
+
+            targetElement.MakeBoundsChangeUndoable(allowMerge: false);
+            targetElement.MoveBy(xMovement, yMovement);
+        }
+
+        /// <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)
+        {
+            foreach (var item in elements)
+            {
+                SnapToEdge(direction, surface, item);
+            }
+            surface.DeselectAllElements();
+        }
+
+        /// <summary>
+        /// Push an element entirely outside the current bounds of the surface, expanding the surface to accomodate it.
+        /// </summary>
+        /// <param name="direction">Direction in which to move element.</param>
+        /// <param name="surface"></param>
+        /// <param name="targetElement"></param>
+        public void PushOut(Direction direction, ISurface surface, IDrawableContainer targetElement)
+        {
+            int left = 0, right = 0, top = 0, bottom = 0;
+            if (direction == Direction.LEFT)
+                left = targetElement.Width;
+            else if (direction == Direction.RIGHT)
+                right = targetElement.Width;
+            else if (direction == Direction.TOP)
+                top = targetElement.Height;
+            else if (direction == Direction.BOTTOM)
+                bottom = targetElement.Height;
+            
+            surface.ResizeCanvas(left, right, top, bottom);
+
+            // Move target object
+            SnapToEdge(direction, surface, targetElement);
+            if (direction == Direction.LEFT || direction == Direction.RIGHT)
+                SnapToEdge(Direction.TOP, surface, targetElement);
+            else if (direction == Direction.TOP || direction == Direction.BOTTOM)
+                SnapToEdge(Direction.LEFT, surface, targetElement);
+            surface.DeselectAllElements();
+        }
     }
 }