Intersections

import React, { useCallback, type MouseEvent } from 'react';
import {
  ReactFlow,
  Background,
  Controls,
  ReactFlowProvider,
  useReactFlow,
  useNodesState,
  type Edge,
  type Node,
} from '@xyflow/react';
 
import '@xyflow/react/dist/style.css';
 
 
const initialNodes: Node[] = [
  {
    id: '1',
    data: { label: 'Node 1' },
    position: { x: 0, y: 0 },
    style: {
      width: 200,
      height: 100,
    },
  },
  {
    id: '2',
    data: { label: 'Node 2' },
    position: { x: 0, y: 150 },
  },
  {
    id: '3',
    data: { label: 'Node 3' },
    position: { x: 250, y: 0 },
  },
  {
    id: '4',
    data: { label: 'Node' },
    position: { x: 350, y: 150 },
    style: {
      width: 50,
      height: 50,
    },
  },
];
 
const initialEdges: Edge[] = [];
 
const BasicFlow = () => {
  const [nodes, setNodes, onNodesChange] = useNodesState(initialNodes);
  const { getIntersectingNodes } = useReactFlow();
 
  const onNodeDrag = useCallback((_: MouseEvent, node: Node) => {
    const intersections = getIntersectingNodes(node).map((n) => n.id);
 
    setNodes((ns) =>
      ns.map((n) => ({
        ...n,
        className: intersections.includes(n.id) ? 'highlight' : '',
      })),
    );
  }, []);
 
  return (
    <ReactFlow
      style={{ backgroundColor: "#F7F9FB" }}
      nodes={nodes}
      edges={initialEdges}
      onNodesChange={onNodesChange}
      onNodeDrag={onNodeDrag}
      className="intersection-flow"
      minZoom={0.2}
      maxZoom={4}
      fitView
      selectNodesOnDrag={false}
    >
      <Background />
      <Controls />
    </ReactFlow>
  );
};
 
export default function App() {
  return (
    <ReactFlowProvider>
      <BasicFlow />
    </ReactFlowProvider>
  );
}