feat: add initial undo/redo system

frontend/package.json

@@ -20,6 +20,7 @@
     "@threlte/extras": "^8.7.5",
     "@threlte/flex": "^1.0.1",
     "@types/three": "^0.159.0",
+    "jsondiffpatch": "^0.6.0",
     "three": "^0.159.0"
   },
   "devDependencies": {

frontend/src/lib/components/Node.svelte

@@ -1,5 +1,6 @@
 <script lang="ts">
   import type { Node } from "$lib/types";
+  import { getContext, onMount } from "svelte";
   import NodeHeader from "./NodeHeader.svelte";
   import NodeParameter from "./NodeParameter.svelte";
   import { activeNodeId, selectedNodes } from "./graph/stores";
@@ -7,9 +8,20 @@
   export let node: Node;
   export let inView = true;
 
+  const updateNodePosition =
+    getContext<(n: Node) => void>("updateNodePosition");
+
   const type = node?.tmp?.type;
 
   const parameters = Object.entries(type?.inputs || {});
+
+  let ref: HTMLDivElement;
+
+  $: if (node && ref) {
+    node.tmp = node.tmp || {};
+    node.tmp.ref = ref;
+    updateNodePosition(node);
+  }
 </script>
 
 <div
@@ -18,7 +30,7 @@
   class:selected={!!$selectedNodes?.has(node.id)}
   class:in-view={inView}
   data-node-id={node.id}
-  bind:this={node.tmp.ref}
+  bind:this={ref}
 >
   <NodeHeader {node} />
 

frontend/src/lib/components/graph/Graph.svelte

@@ -56,10 +56,20 @@
   function updateNodePosition(node: NodeType) {
     node.tmp = node.tmp || {};
     if (node?.tmp?.ref) {
+      if (node.tmp["x"] !== undefined && node.tmp["y"] !== undefined) {
+        node.tmp.ref.style.setProperty("--nx", `${node.tmp.x * 10}px`);
+        node.tmp.ref.style.setProperty("--ny", `${node.tmp.y * 10}px`);
+        if (node.tmp.x === node.position.x && node.tmp.y === node.position.y) {
+          delete node.tmp.x;
+          delete node.tmp.y;
+        }
+      } else {
         node.tmp.ref.style.setProperty("--nx", `${node.position.x * 10}px`);
         node.tmp.ref.style.setProperty("--ny", `${node.position.y * 10}px`);
       }
     }
+  }
+  setContext("updateNodePosition", updateNodePosition);
 
   const nodeHeightCache: Record<string, number> = {};
   function getNodeHeight(nodeTypeId: string) {
@@ -100,7 +110,7 @@
         if (edge[3] === index) {
           node = edge[0];
           index = edge[1];
-          position = getSocketPosition({ node, index });
+          position = getSocketPosition(node, index);
           graph.removeEdge(edge);
           break;
         }
@@ -120,7 +130,7 @@
         return {
           node,
           index,
-          position: getSocketPosition({ node, index }),
+          position: getSocketPosition(node, index),
         };
       });
     $possibleSocketIds = new Set(
@@ -142,23 +152,23 @@
   }
 
   function getSocketPosition(
-    socket: Omit<Socket, "position">,
+    node: NodeType,
+    index: string | number,
   ): [number, number] {
-    if (typeof socket.index === "number") {
+    if (typeof index === "number") {
       return [
-        socket.node.position.x + 5,
-        socket.node.position.y + 0.625 + 2.5 * socket.index,
+        (node?.tmp?.x ?? node.position.x) + 5,
+        (node?.tmp?.y ?? node.position.y) + 0.625 + 2.5 * index,
       ];
     } else {
-      const _index = Object.keys(socket.node.tmp?.type?.inputs || {}).indexOf(
-        socket.index,
-      );
+      const _index = Object.keys(node.tmp?.type?.inputs || {}).indexOf(index);
       return [
-        socket.node.position.x,
-        socket.node.position.y + 2.5 + 2.5 * _index,
+        node?.tmp?.x ?? node.position.x,
+        (node?.tmp?.y ?? node.position.y) + 2.5 + 2.5 * _index,
       ];
     }
   }
+  setContext("getSocketPosition", getSocketPosition);
 
   function setMouseFromEvent(event: MouseEvent) {
     const x = event.clientX;
@@ -230,16 +240,15 @@
     if ($selectedNodes?.size) {
       for (const nodeId of $selectedNodes) {
         const n = graph.getNode(nodeId);
-        if (!n) continue;
-        n.position.x = (n?.tmp?.downX || 0) - vecX;
-        n.position.y = (n?.tmp?.downY || 0) - vecY;
+        if (!n?.tmp) continue;
+        n.tmp.x = (n?.tmp?.downX || 0) - vecX;
+        n.tmp.y = (n?.tmp?.downY || 0) - vecY;
         updateNodePosition(n);
       }
     }
 
-    node.position.x = newX;
-    node.position.y = newY;
-    node.position = node.position;
+    node.tmp.x = newX;
+    node.tmp.y = newY;
 
     updateNodePosition(node);
 
@@ -306,7 +315,41 @@
   }
 
   function handleKeyDown(event: KeyboardEvent) {
-    if (event.key === "Delete") {
+    if (event.key === "Escape") {
+      $activeNodeId = -1;
+      $selectedNodes?.clear();
+      $selectedNodes = $selectedNodes;
+    }
+
+    if (event.key === "a" && event.ctrlKey) {
+      $selectedNodes = new Set($nodes.keys());
+    }
+
+    if (event.key === "c" && event.ctrlKey) {
+    }
+
+    if (event.key === "v" && event.ctrlKey) {
+    }
+
+    if (event.key === "z" && event.ctrlKey) {
+      graph.history.undo();
+      for (const node of $nodes.values()) {
+        updateNodePosition(node);
+      }
+    }
+
+    if (event.key === "y" && event.ctrlKey) {
+      graph.history.redo();
+      for (const node of $nodes.values()) {
+        updateNodePosition(node);
+      }
+    }
+
+    if (
+      event.key === "Delete" ||
+      event.key === "Backspace" ||
+      event.key === "x"
+    ) {
       if ($activeNodeId !== -1) {
         const node = graph.getNode($activeNodeId);
         if (node) {
@@ -349,38 +392,52 @@
       activeNode.tmp = activeNode.tmp || {};
       activeNode.tmp.isMoving = false;
       const snapLevel = getSnapLevel();
-      const fx = snapToGrid(activeNode.position.x, 5 / snapLevel);
-      const fy = snapToGrid(activeNode.position.y, 5 / snapLevel);
-      if ($selectedNodes) {
-        for (const nodeId of $selectedNodes) {
-          const node = graph.getNode(nodeId);
+      activeNode.position.x = snapToGrid(
+        activeNode?.tmp?.x ?? activeNode.position.x,
+        5 / snapLevel,
+      );
+      activeNode.position.y = snapToGrid(
+        activeNode?.tmp?.y ?? activeNode.position.y,
+        5 / snapLevel,
+      );
+      const nodes = [
+        ...[...($selectedNodes?.values() || [])].map((id) => graph.getNode(id)),
+      ] as NodeType[];
+
+      const vec = [
+        activeNode.position.x - (activeNode?.tmp.x || 0),
+        activeNode.position.y - (activeNode?.tmp.y || 0),
+      ];
+
+      for (const node of nodes) {
         if (!node) continue;
         node.tmp = node.tmp || {};
-          node.tmp.snapX = node.position.x - (activeNode.position.x - fx);
-          node.tmp.snapY = node.position.y - (activeNode.position.y - fy);
+        const { x, y } = node.tmp;
+        if (x !== undefined && y !== undefined) {
+          node.position.x = x + vec[0];
+          node.position.y = y + vec[1];
         }
       }
+      nodes.push(activeNode);
       animate(500, (a: number) => {
-        activeNode.position.x = lerp(activeNode.position.x, fx, a);
-        activeNode.position.y = lerp(activeNode.position.y, fy, a);
-        updateNodePosition(activeNode);
-
-        if ($selectedNodes) {
-          for (const nodeId of $selectedNodes) {
-            const node = graph.getNode(nodeId);
-            if (!node) continue;
-            node.position.x = lerp(node.position.x, node?.tmp?.snapX || 0, a);
-            node.position.y = lerp(node.position.y, node?.tmp?.snapY || 0, a);
+        for (const node of nodes) {
+          if (
+            node?.tmp &&
+            node.tmp["x"] !== undefined &&
+            node.tmp["y"] !== undefined
+          ) {
+            node.tmp.x = lerp(node.tmp.x, node.position.x, a);
+            node.tmp.y = lerp(node.tmp.y, node.position.y, a);
             updateNodePosition(node);
-          }
-        }
-
-        if (activeNode?.tmp?.isMoving) {
+            if (node?.tmp?.isMoving) {
               return false;
             }
+          }
+        }
 
         $edges = $edges;
       });
+      graph.history.save();
     } else if ($hoveredSocket && $activeSocket) {
       if (
         typeof $hoveredSocket.index === "number" &&
@@ -403,6 +460,7 @@
           $hoveredSocket.index,
         );
       }
+      graph.history.save();
     }
 
     mouseDown = null;

frontend/src/lib/components/graph/GraphView.svelte

@@ -14,14 +14,16 @@
 
   const isNodeInView = getContext<(n: NodeType) => boolean>("isNodeInView");
 
+  const getSocketPosition =
+    getContext<(node: NodeType, index: string | number) => [number, number]>(
+      "getSocketPosition",
+    );
+
   function getEdgePosition(edge: EdgeType) {
-    const index = Object.keys(edge[2].tmp?.type?.inputs || {}).indexOf(edge[3]);
-    return [
-      edge[0].position.x + 5,
-      edge[0].position.y + 0.625 + edge[1] * 2.5,
-      edge[2].position.x,
-      edge[2].position.y + 2.5 + index * 2.5,
-    ];
+    const pos1 = getSocketPosition(edge[0], edge[1]);
+    const pos2 = getSocketPosition(edge[2], edge[3]);
+
+    return [pos1[0], pos1[1], pos2[0], pos2[1]];
   }
 
   onMount(() => {

frontend/src/lib/graph-manager.ts

@@ -1,5 +1,6 @@
 import { writable, type Writable } from "svelte/store";
 import type { Graph, NodeRegistry as INodeRegistry, NodeType, Node, Edge, Socket } from "./types";
+import { HistoryManager } from "./history-manager";
 
 const nodeTypes: NodeType[] = [
   {
@@ -43,6 +44,8 @@ export class GraphManager {
   private _edges: Edge[] = [];
   edges: Writable<Edge[]> = writable([]);
 
+  history: HistoryManager = new HistoryManager(this);
+
   private constructor(private graph: Graph, private nodeRegistry: NodeRegistry = new NodeRegistry()) {
     this.nodes.subscribe((nodes) => {
       this._nodes = nodes;
@@ -50,38 +53,30 @@ export class GraphManager {
     this.edges.subscribe((edges) => {
       this._edges = edges;
     });
-
-    globalThis["serialize"] = () => this.serialize();
   }
 
-  serialize() {
+  serialize(): Graph {
     const nodes = Array.from(this._nodes.values()).map(node => ({
       id: node.id,
-      position: node.position,
+      position: { x: node.position.x, y: node.position.y },
       type: node.type,
       props: node.props,
     }));
-    const edges = this._edges.map(edge => [edge[0].id, edge[1], edge[2].id, edge[3]]);
+    const edges = this._edges.map(edge => [edge[0].id, edge[1], edge[2].id, edge[3]]) as Graph["edges"];
     return { nodes, edges };
   }
 
-  async load() {
-
-    const nodes = new Map(this.graph.nodes.map(node => [node.id, node]));
-
-    for (const node of nodes.values()) {
+  private _init(graph: Graph) {
+    const nodes = new Map(graph.nodes.map(node => {
       const nodeType = this.nodeRegistry.getNode(node.type);
-      if (!nodeType) {
-        console.error(`Node type not found: ${node.type}`);
-        this.status.set("error");
-        return;
-      }
+      if (nodeType) {
         node.tmp = node.tmp || {};
         node.tmp.type = nodeType;
       }
+      return [node.id, node]
+    }));
 
-
-    this.edges.set(this.graph.edges.map((edge) => {
+    this.edges.set(graph.edges.map((edge) => {
       const from = nodes.get(edge[0]);
       const to = nodes.get(edge[2]);
       if (!from || !to) {
@@ -101,7 +96,25 @@ export class GraphManager {
 
     this.nodes.set(nodes);
 
+  }
+
+  async load() {
+
+    for (const node of this.graph.nodes) {
+      const nodeType = this.nodeRegistry.getNode(node.type);
+      if (!nodeType) {
+        console.error(`Node type not found: ${node.type}`);
+        this.status.set("error");
+        return;
+      }
+      node.tmp = node.tmp || {};
+      node.tmp.type = nodeType;
+    }
+
+    this._init(this.graph);
+
     this.status.set("idle");
+    this.history.save();
   }
 
 
@@ -155,6 +168,7 @@ export class GraphManager {
       nodes.delete(node.id);
       return nodes;
     });
+    this.history.save();
   }
 
   createEdge(from: Node, fromSocket: number, to: Node, toSocket: string) {
@@ -181,6 +195,8 @@ export class GraphManager {
     this.edges.update((edges) => {
       return [...edges.filter(e => e[2].id !== to.id || e[3] !== toSocket), [from, fromSocket, to, toSocket]];
     });
+
+    this.history.save();
   }
 
   getParentsOfNode(node: Node) {
@@ -257,6 +273,7 @@ export class GraphManager {
     this.edges.update((edges) => {
       return edges.filter((e) => e[0].id !== id0 || e[1] !== sid0 || e[2].id !== id2 || e[3] !== sid2);
     });
+    this.history.save();
   }
 
   getEdgesToNode(node: Node) {
@@ -328,7 +345,5 @@ export class GraphManager {
     return new GraphManager(graph);
   }
 
-
 }
 
-

frontend/src/lib/history-manager.ts

@@ -0,0 +1,95 @@
+import type { GraphManager } from "./graph-manager";
+import { create, type Delta } from "jsondiffpatch";
+import type { Graph } from "./types";
+
+
+const diff = create({
+  objectHash: function (obj, index) {
+    if (obj === null) return obj;
+    if ("id" in obj) return obj.id;
+    if (Array.isArray(obj)) {
+      return obj.join("-")
+    }
+    return obj?.id || obj._id || '$$index:' + index;
+  }
+})
+
+export class HistoryManager {
+
+  index: number = -1;
+  history: Delta[] = [];
+  private initialState: Graph | undefined;
+  private prevState: Graph | undefined;
+  private timeout: number | undefined;
+
+  private opts = {
+    debounce: 400,
+    maxHistory: 100,
+  }
+
+
+  constructor(private manager: GraphManager, { maxHistory = 100, debounce = 100 } = {}) {
+    this.history = [];
+    this.index = -1;
+    this.opts.debounce = debounce;
+    this.opts.maxHistory = maxHistory;
+  }
+
+  save() {
+    if (!this.prevState) {
+      this.prevState = this.manager.serialize();
+      this.initialState = globalThis.structuredClone(this.prevState);
+    } else {
+      if (this.timeout) {
+        clearTimeout(this.timeout);
+      }
+
+      this.timeout = setTimeout(() => {
+        const newState = this.manager.serialize();
+        const delta = diff.diff(this.prevState, newState);
+        if (delta) {
+          // Add the delta to history
+          if (this.index < this.history.length - 1) {
+            // Clear the history after the current index if new changes are made
+            this.history.splice(this.index + 1);
+          }
+
+          this.history.push(delta);
+          this.index++;
+
+          // Limit the size of the history
+          if (this.history.length > this.opts.maxHistory) {
+            this.history.shift();
+          }
+        }
+        this.prevState = newState;
+      }, this.opts.debounce) as unknown as number;
+    }
+  }
+
+  undo() {
+    if (this.index > 0) {
+      const delta = this.history[this.index];
+      const prevState = diff.unpatch(this.prevState, delta) as Graph;
+      this.manager._init(prevState);
+      this.index--;
+      this.prevState = prevState;
+    } else if (this.index === 0 && this.initialState) {
+      this.manager._init(globalThis.structuredClone(this.initialState));
+      console.log("Reached start", this.index, this.history.length)
+    }
+  }
+
+  redo() {
+    if (this.index < this.history.length - 1) {
+      const nextIndex = this.index + 1;
+      const delta = this.history[nextIndex];
+      const nextState = diff.patch(this.prevState, delta) as Graph;
+      this.manager._init(nextState);
+      this.index = nextIndex;
+      this.prevState = nextState;
+    } else {
+      console.log("Reached end")
+    }
+  }
+}

frontend/src/lib/types/index.ts

@@ -11,8 +11,8 @@ export type Node = {
     type?: NodeType;
     downX?: number;
     downY?: number;
-    snapX?: number;
-    snapY?: number;
+    x?: number;
+    y?: number;
     ref?: HTMLElement;
     visible?: boolean;
     isMoving?: boolean;

pnpm-lock.yaml

@@ -35,6 +35,9 @@ importers:
       '@types/three':
         specifier: ^0.159.0
         version: 0.159.0
+      jsondiffpatch:
+        specifier: ^0.6.0
+        version: 0.6.0
       three:
         specifier: ^0.159.0
         version: 0.159.0
@@ -1146,6 +1149,10 @@ packages:
   /@types/cookie@0.6.0:
     resolution: {integrity: sha512-4Kh9a6B2bQciAhf7FSuMRRkUWecJgJu9nPnx3yzpsfXX/c50REIqpHY4C82bXP90qrLtXtkDxTZosYO3UpOwlA==}
 
+  /@types/diff-match-patch@1.0.36:
+    resolution: {integrity: sha512-xFdR6tkm0MWvBfO8xXCSsinYxHcqkQUlcHeSpMC2ukzOb6lwQAfDmW+Qt0AvlGd8HpsS28qKsB+oPeJn9I39jg==}
+    dev: false
+
   /@types/estree@1.0.5:
     resolution: {integrity: sha512-/kYRxGDLWzHOB7q+wtSUQlFrtcdUccpfy+X+9iMBpHK8QLLhx2wIPYuS5DYtR9Wa/YlZAbIovy7qVdB1Aq6Lyw==}
 
@@ -1803,6 +1810,10 @@ packages:
     resolution: {integrity: sha512-wlwEkqcsaxvPJML+rDh/2iS824jbREk6DUMUKkEaSlxdYHeS43cClJtsWglvw2RfeXGm6ohKDqsXteJ5sP5enA==}
     dev: true
 
+  /diff-match-patch@1.0.5:
+    resolution: {integrity: sha512-IayShXAgj/QMXgB0IWmKx+rOPuGMhqm5w6jvFxmVenXKIzRqTAAsbBPT3kWQeGANj3jGgvcvv4yK6SxqYmikgw==}
+    dev: false
+
   /dir-glob@3.0.1:
     resolution: {integrity: sha512-WkrWp9GR4KXfKGYzOLmTuGVi1UWFfws377n9cc55/tb6DuqyF6pcQ5AbiHEshaDpY9v6oaSr2XCDidGmMwdzIA==}
     engines: {node: '>=8'}
@@ -2638,6 +2649,16 @@ packages:
   /jsonc-parser@3.2.1:
     resolution: {integrity: sha512-AilxAyFOAcK5wA1+LeaySVBrHsGQvUFCDWXKpZjzaL0PqW+xfBOttn8GNtWKFWqneyMZj41MWF9Kl6iPWLwgOA==}
 
+  /jsondiffpatch@0.6.0:
+    resolution: {integrity: sha512-3QItJOXp2AP1uv7waBkao5nCvhEv+QmJAd38Ybq7wNI74Q+BBmnLn4EDKz6yI9xGAIQoUF87qHt+kc1IVxB4zQ==}
+    engines: {node: ^18.0.0 || >=20.0.0}
+    hasBin: true
+    dependencies:
+      '@types/diff-match-patch': 1.0.36
+      chalk: 5.3.0
+      diff-match-patch: 1.0.5
+    dev: false
+
   /jsonfile@6.1.0:
     resolution: {integrity: sha512-5dgndWOriYSm5cnYaJNhalLNDKOqFwyDB/rr1E9ZsGciGvKPs8R2xYGCacuf3z6K1YKDz182fd+fY3cn3pMqXQ==}
     dependencies: