add set and update functions to nodes,edges & viewport hooks

packages/svelte/src/lib/hooks/useNodesEdgesViewport.svelte.ts

@@ -1,4 +1,6 @@
 import { useStore } from '$lib/store';
+import type { Edge, Node } from '$lib/types';
+import type { Viewport } from '@xyflow/system';
 
 /**
  * Hook for getting the current nodes from the store.
@@ -12,8 +14,14 @@ export function useNodes() {
     get current() {
       return store.nodes;
     },
-    set current(val) {
+    set current(nodes) {
-      store.nodes = val;
+      store.nodes = nodes;
+    },
+    update(updateFn: (nodes: Node[]) => Node[]) {
+      store.nodes = updateFn(store.nodes);
+    },
+    set(nodes: Node[]) {
+      store.nodes = nodes;
     }
   };
 }
@@ -30,8 +38,14 @@ export function useEdges() {
     get current() {
       return store.edges;
     },
-    set current(val) {
+    set current(edges) {
-      store.edges = val;
+      store.edges = edges;
+    },
+    update(updateFn: (edges: Edge[]) => Edge[]) {
+      store.edges = updateFn(store.edges);
+    },
+    set(edges: Edge[]) {
+      store.edges = edges;
     }
   };
 }
@@ -48,8 +62,14 @@ export function useViewport() {
     get current() {
       return store.viewport;
     },
-    set current(val) {
+    set current(viewport: Viewport) {
-      store.viewport = val;
+      store.viewport = viewport;
+    },
+    update(updateFn: (viewport: Viewport) => Viewport) {
+      store.viewport = updateFn(store.viewport);
+    },
+    set(viewport: Viewport) {
+      store.viewport = viewport;
     }
   };
 }