voxel editor undo/redo

src/components/voxelEditor/VoxelEditorPage.tsx

@@ -1,11 +1,11 @@
 import { Canvas } from '@react-three/fiber';
 import { useParams, useNavigate, Link } from 'react-router-dom';
 import { observer } from 'mobx-react-lite';
-import { useState, useCallback, useEffect } from 'react';
+import { useState, useCallback, useEffect, useRef } from 'react';
 import { state } from '../../state';
 import type { Voxel, V3 } from '../../types';
 import { VoxelEditorScene } from './VoxelEditorScene';
-import { IconArrowLeft, IconPlus, IconTrash } from '@tabler/icons-react';
+import { IconArrowLeft, IconArrowBackUp, IconArrowForwardUp, IconPlus, IconTrash } from '@tabler/icons-react';
 
 const PALETTE = [
     '#ffffff', '#cccccc', '#999999', '#555555', '#222222',
@@ -14,11 +14,19 @@ const PALETTE = [
     '#e8b820', '#484040', '#d0c8b8', '#808080', '#181414',
 ];
 
+type HistoryEntry =
+    | { type: 'add'; voxel: Voxel }
+    | { type: 'remove'; voxel: Voxel };
+
 export const VoxelEditorPage = observer(function () {
     const { id } = useParams<{ id: string }>();
     const navigate = useNavigate();
     const [mode, setMode] = useState<'add' | 'remove'>('add');
     const [color, setColor] = useState('#808080');
+    const [canUndo, setCanUndo] = useState(false);
+    const [canRedo, setCanRedo] = useState(false);
+    const history = useRef<HistoryEntry[]>([]);
+    const future = useRef<HistoryEntry[]>([]);
 
     const objectType = id ? state.world.getObjectTypeById(id) : undefined;
 
@@ -28,14 +36,67 @@ export const VoxelEditorPage = observer(function () {
         };
     }, [id]);
 
-    const handleAdd = useCallback((voxel: Voxel) => {
-        if (id) state.worldEditor.addVoxelToObjectType(id, voxel);
+    function pushHistory(entry: HistoryEntry) {
+        history.current.push(entry);
+        future.current = [];
+        setCanUndo(true);
+        setCanRedo(false);
+    }
+
+    const undo = useCallback(() => {
+        const entry = history.current.pop();
+        if (!entry || !id) return;
+        if (entry.type === 'add') {
+            state.worldEditor.removeVoxelFromObjectType(id, entry.voxel.position);
+        } else {
+            state.worldEditor.addVoxelToObjectType(id, entry.voxel);
+        }
+        future.current.push(entry);
+        setCanUndo(history.current.length > 0);
+        setCanRedo(true);
     }, [id]);
 
-    const handleRemove = useCallback((position: V3) => {
-        if (id) state.worldEditor.removeVoxelFromObjectType(id, position);
+    const redo = useCallback(() => {
+        const entry = future.current.pop();
+        if (!entry || !id) return;
+        if (entry.type === 'add') {
+            state.worldEditor.addVoxelToObjectType(id, entry.voxel);
+        } else {
+            state.worldEditor.removeVoxelFromObjectType(id, entry.voxel.position);
+        }
+        history.current.push(entry);
+        setCanUndo(true);
+        setCanRedo(future.current.length > 0);
     }, [id]);
 
+    useEffect(() => {
+        function onKeyDown(e: KeyboardEvent) {
+            if (!e.ctrlKey) return;
+            if (e.key === 'z' && !e.shiftKey) { e.preventDefault(); undo(); }
+            if (e.key === 'y' || (e.key === 'z' && e.shiftKey)) { e.preventDefault(); redo(); }
+        }
+        window.addEventListener('keydown', onKeyDown);
+        return () => window.removeEventListener('keydown', onKeyDown);
+    }, [undo, redo]);
+
+    function handleAdd(voxel: Voxel) {
+        if (!id) return;
+        state.worldEditor.addVoxelToObjectType(id, voxel);
+        pushHistory({ type: 'add', voxel });
+    }
+
+    function handleRemove(position: V3) {
+        if (!id || !objectType) return;
+        const voxel = objectType.voxels.find(v =>
+            v.position[0] === position[0] &&
+            v.position[1] === position[1] &&
+            v.position[2] === position[2]
+        );
+        if (!voxel) return;
+        state.worldEditor.removeVoxelFromObjectType(id, position);
+        pushHistory({ type: 'remove', voxel });
+    }
+
     if (!objectType) {
         return (
             <div style={{ color: 'white', padding: 24 }}>
@@ -47,15 +108,19 @@ export const VoxelEditorPage = observer(function () {
     return (
         <div style={{ position: 'fixed', inset: 0, background: '#1a1a2e', display: 'flex', flexDirection: 'column' }}>
             {/* Top bar */}
-            <div style={{ display: 'flex', alignItems: 'center', gap: 12, padding: '8px 12px', background: '#11111f', flexShrink: 0 }}>
-                <button
-                    onClick={() => navigate(`/editor/objectType/${id}`)}
-                    style={btnStyle}
-                >
+            <div style={{ display: 'flex', alignItems: 'center', gap: 8, padding: '8px 12px', background: '#11111f', flexShrink: 0 }}>
+                <button onClick={() => navigate(`/editor/objectType/${id}`)} style={btnStyle}>
                     <IconArrowLeft size={20} />
                 </button>
                 <span style={{ color: '#ccc', fontWeight: 600 }}>{objectType.name}</span>
                 <span style={{ color: '#666', fontSize: 13 }}>{objectType.voxels.length} voxels</span>
+                <div style={{ flex: 1 }} />
+                <button onClick={undo} disabled={!canUndo} style={{ ...btnStyle, opacity: canUndo ? 1 : 0.35 }}>
+                    <IconArrowBackUp size={20} />
+                </button>
+                <button onClick={redo} disabled={!canRedo} style={{ ...btnStyle, opacity: canRedo ? 1 : 0.35 }}>
+                    <IconArrowForwardUp size={20} />
+                </button>
             </div>
 
             {/* 3D canvas */}