chore: setup monorepo using preconstruct

packages/core/src/hooks/useNodesEdgesState.ts

@@ -0,0 +1,34 @@
+import { useState, useCallback, SetStateAction, Dispatch } from 'react';
+
+import { applyNodeChanges, applyEdgeChanges } from '../utils/changes';
+import { Node, NodeChange, Edge, EdgeChange } from '../types';
+
+type ApplyChanges<ItemType, ChangesType> = (changes: ChangesType[], items: ItemType[]) => ItemType[];
+type OnChange<ChangesType> = (changes: ChangesType[]) => void;
+
+// returns a hook that can be used liked this:
+// const [nodes, setNodes, onNodesChange] = useNodesState(initialNodes);
+function createUseItemsState(
+  applyChanges: ApplyChanges<Node, NodeChange>
+): <NodeData = any>(
+  initialItems: Node<NodeData>[]
+) => [Node<NodeData>[], Dispatch<SetStateAction<Node<NodeData>[]>>, OnChange<NodeChange>];
+function createUseItemsState(
+  applyChanges: ApplyChanges<Edge, EdgeChange>
+): <EdgeData = any>(
+  initialItems: Edge<EdgeData>[]
+) => [Edge<EdgeData>[], Dispatch<SetStateAction<Edge<EdgeData>[]>>, OnChange<EdgeChange>];
+function createUseItemsState(
+  applyChanges: ApplyChanges<any, any>
+): (initialItems: any[]) => [any[], Dispatch<SetStateAction<any[]>>, OnChange<any>] {
+  return (initialItems: any[]) => {
+    const [items, setItems] = useState(initialItems);
+
+    const onItemsChange = useCallback((changes: any[]) => setItems((items: any) => applyChanges(changes, items)), []);
+
+    return [items, setItems, onItemsChange];
+  };
+}
+
+export const useNodesState = createUseItemsState(applyNodeChanges);
+export const useEdgesState = createUseItemsState(applyEdgeChanges);