From 20f724c59843caec982981ec7434e76454458835 Mon Sep 17 00:00:00 2001
From: Ryan Reilly <ryanreilly703@gmail.com>
Date: Sun, 17 Mar 2024 21:56:39 -0400
Subject: [PATCH] Ctrl+Y working for draw tools

---
 src/History/DrawModeStack.ts |  8 +++++++
 src/TreeContext.ts           | 45 ++++++++++++++++++++++++++++++------
 src/index.ts                 |  2 +-
 3 files changed, 47 insertions(+), 8 deletions(-)

diff --git a/src/History/DrawModeStack.ts b/src/History/DrawModeStack.ts
index bab308bb..f3926034 100644
--- a/src/History/DrawModeStack.ts
+++ b/src/History/DrawModeStack.ts
@@ -28,6 +28,14 @@ export class DrawModeStack {
         return poppedNode;
     }
 
+    public topple(indexToToppleFrom: number): void {
+        this.history.splice(indexToToppleFrom, this.history.length - 1 - indexToToppleFrom);
+    }
+
+    public clear(): void {
+        this.history = [];
+    }
+
     public peek(): DrawModeNode {
         return this.history.length !== 0
             ? this.history[this.history.length - 1]
diff --git a/src/TreeContext.ts b/src/TreeContext.ts
index 6bf6817e..c4bed11e 100644
--- a/src/TreeContext.ts
+++ b/src/TreeContext.ts
@@ -47,8 +47,12 @@ export class TreeContext {
     //Current AEGTree on canvas.
     public static tree: AEGTree = new AEGTree();
 
-    //For undoing and redoing changes in Draw Mode.
-    public static drawHistory: DrawModeStack = new DrawModeStack();
+    //For undoing changes in Draw Mode.
+    public static drawHistoryUndoStack: DrawModeStack = new DrawModeStack();
+
+    public static drawHistoryRedoStack: DrawModeStack = new DrawModeStack();
+
+    private static recentlyUndoneOrRedoneMove = false;
 
     //The proof is a series of ProofNodes.
     public static proof: ProofNode[] = [];
@@ -71,29 +75,56 @@ export class TreeContext {
      * @param newlyAppliedStep Incoming DrawModeMove.
      */
     public static pushToDrawStack(newlyAppliedStep: DrawModeMove): void {
-        this.drawHistory.push(new DrawModeNode(this.tree, newlyAppliedStep));
+        if (this.recentlyUndoneOrRedoneMove) {
+            this.drawHistoryRedoStack.clear();
+        }
+        this.drawHistoryUndoStack.push(new DrawModeNode(this.tree, newlyAppliedStep));
     }
 
     /**
      * Pops the most recent draw mode move from drawHistory and changes tree accordingly.
      */
     public static undoDrawStep(): void {
-        const mostRecentStep: DrawModeNode | null = this.drawHistory.pop();
+        const mostRecentStep: DrawModeNode | null = this.drawHistoryUndoStack.pop();
 
         let newTree: AEGTree;
 
-        if (mostRecentStep === null || this.drawHistory.peek() === null) {
+        if (mostRecentStep === null || this.drawHistoryUndoStack.peek() === null) {
             newTree = new AEGTree();
             this.tree = newTree;
             redrawTree(newTree);
             return;
         }
 
-        this.tree = new AEGTree(this.drawHistory.peek().tree.sheet);
+        this.drawHistoryRedoStack.push(mostRecentStep);
+
+        this.tree = new AEGTree(this.drawHistoryUndoStack.peek().tree.sheet);
+
+        newTree = new AEGTree(this.drawHistoryUndoStack.peek().tree.sheet);
+
+        redrawTree(newTree);
+
+        this.recentlyUndoneOrRedoneMove = true;
+    }
+
+    public static redoDrawStep(): void {
+        const mostRecentStep: DrawModeNode | null = this.drawHistoryRedoStack.pop();
+
+        if (mostRecentStep === null || this.drawHistoryUndoStack.peek() === null) {
+            return;
+        }
+
+        this.drawHistoryUndoStack.push(mostRecentStep);
 
-        newTree = new AEGTree(this.drawHistory.peek().tree.sheet);
+        //i seem to have accidentally made the correct procedure by copy/pasting the incorrect name
+        //here and below are all supposed to be drawHistoryRedoStack but that ruins the behavior
+        this.tree = new AEGTree(this.drawHistoryUndoStack.peek().tree.sheet);
+
+        const newTree: AEGTree = new AEGTree(this.drawHistoryUndoStack.peek().tree.sheet);
 
         redrawTree(newTree);
+
+        this.recentlyUndoneOrRedoneMove = true;
     }
 
     /**
diff --git a/src/index.ts b/src/index.ts
index bf209f0b..67642794 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -316,7 +316,7 @@ async function handleUndo(): Promise<void> {
 }
 
 async function handleRedo(): Promise<void> {
-    console.log("");
+    TreeContext.redoDrawStep();
 }
 
 //TODO: replace all of this with polymorphism -James