Undo and Redo Operations Functional, with some caveats

2018-12-01 19:41:40 -08:00
parent 92249cac8f
commit 17b1e56180
13 changed files with 563 additions and 81 deletions
@@ -0,0 +1,93 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Forms;
+
+namespace SpriteMapEditor.SpriteMapModifications
+{
+    class History
+    {
+        private List<ISpriteMapModification> changes;
+        private int position;
+
+        public bool CanUndo
+        {
+             get { return position >= 0 && changes.Count > 0; }
+        }
+
+        public bool CanRedo
+        {
+            get { return position < changes.Count - 1; }
+        }
+
+        public History()
+        {
+            changes = new List<ISpriteMapModification>();
+        }
+
+        public void Add(ISpriteMapModification change)
+        {
+            if (position < changes.Count - 1)
+            {
+                changes.RemoveRange(position + 1, changes.Count - 1 - position);
+            }
+            changes.Add(change);
+            position = changes.Count - 1;
+            //Console.WriteLine("Available Undo Steps: " + changes.Count + "; Current Undo Position: " + position);
+        }
+
+        public void Undo()
+        {
+            if (CanUndo)
+            { 
+                changes[position].Undo();
+                position--;
+            }
+        }
+
+        public void Undo(ListBox listBox)
+        {
+            if (CanUndo)
+            {
+                ModHelper.UndoAndRestoreSelection(changes[position], listBox);
+                position--;
+            }
+        }
+
+        public void Redo()
+        {
+            if (CanRedo)
+            {
+                changes[position + 1].Do();
+                position++;
+            }
+        }
+
+        public void Redo(ListBox listBox)
+        {
+            if (CanRedo)
+            {
+                ModHelper.RedoAndRestoreSelection(changes[position + 1], listBox);
+                position++;
+            }
+        }
+
+        public string NextUndoString()
+        {
+            if (!CanUndo)
+                return "Undo...";
+            else
+                return "Undo " + changes[position];
+        }
+
+        public string NextRedoString()
+        {
+            if (!CanRedo)
+                return "Redo...";
+            else
+                return "Redo " + changes[position + 1];
+        }
+    }
+}