refactor(floating-edge-example): cleanup

example/src/FloatingEdges/FloatingConnectionLine.tsx

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+import { FC } from 'react';
+import { getBezierPath, ConnectionLineComponentProps } from 'react-flow-renderer';
+
+import { getArrow } from './utils';
+
+const FloatingConnectionLine: FC<ConnectionLineComponentProps> = ({
+  targetX,
+  targetY,
+  sourcePosition,
+  targetPosition,
+  sourceNode,
+}) => {
+  if (!sourceNode) {
+    return null;
+  }
+
+  const targetNode = { __rf: { width: 1, height: 1, position: { x: targetX, y: targetY } } };
+  const { sx, sy } = getArrow(sourceNode, targetNode);
+  const d = getBezierPath({
+    sourceX: sx,
+    sourceY: sy,
+    sourcePosition,
+    targetPosition,
+    targetX,
+    targetY,
+  });
+
+  return (
+    <g>
+      <path fill="none" stroke="#222" strokeWidth={1.5} className="animated" d={d} />
+      <circle cx={targetX} cy={targetY} fill="#fff" r={3} stroke="#222" strokeWidth={1.5} />
+    </g>
+  );
+};
+
+export default FloatingConnectionLine;

example/src/FloatingEdges/FloatingEdge.tsx

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+import { FC, useMemo, CSSProperties } from 'react';
+import { EdgeProps, getMarkerEnd, useStoreState, getBezierPath } from 'react-flow-renderer';
+
+import { getArrow } from './utils';
+
+const FloatingEdge: FC<EdgeProps> = ({ id, source, target, arrowHeadType, markerEndId, style }) => {
+  const nodes = useStoreState((state) => state.nodes);
+  const markerEnd = getMarkerEnd(arrowHeadType, markerEndId);
+
+  const sourceNode = useMemo(() => nodes.find((n) => n.id === source), [source, nodes]);
+  const targetNode = useMemo(() => nodes.find((n) => n.id === target), [target, nodes]);
+
+  if (!sourceNode || !targetNode) {
+    return null;
+  }
+
+  const { sx, sy, tx, ty, sourcePos, targetPos } = getArrow(sourceNode, targetNode);
+
+  const d = getBezierPath({
+    sourceX: sx,
+    sourceY: sy,
+    sourcePosition: sourcePos,
+    targetPosition: targetPos,
+    targetX: tx,
+    targetY: ty,
+  });
+
+  return (
+    <g className="react-flow__connection">
+      <path id={id} className="react-flow__edge-path" d={d} markerEnd={markerEnd} style={style as CSSProperties} />
+    </g>
+  );
+};
+
+export default FloatingEdge;

example/src/FloatingEdges/index.tsx

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+import React, { useState } from 'react';
+
+import ReactFlow, {
+  removeElements,
+  addEdge,
+  MiniMap,
+  Controls,
+  Background,
+  OnLoadParams,
+  EdgeTypesType,
+  Elements,
+  Connection,
+  Edge,
+  ArrowHeadType,
+} from 'react-flow-renderer';
+
+import FloatingEdge from './FloatingEdge';
+import FloatingConnectionLine from './FloatingConnectionLine';
+import { createElements } from './utils';
+
+const onLoad = (reactFlowInstance: OnLoadParams) => reactFlowInstance.fitView();
+
+const initialElements: Elements = createElements();
+
+const edgeTypes: EdgeTypesType = {
+  floating: FloatingEdge,
+};
+
+const NodeAsHandleFlow = () => {
+  const [elements, setElements] = useState<Elements>(initialElements);
+
+  const onElementsRemove = (elementsToRemove: Elements) => setElements((els) => removeElements(elementsToRemove, els));
+  const onConnect = (params: Connection | Edge) =>
+    setElements((els) => addEdge({ ...params, type: 'floating', arrowHeadType: ArrowHeadType.Arrow }, els));
+
+  return (
+    <ReactFlow
+      elements={elements}
+      onElementsRemove={onElementsRemove}
+      onConnect={onConnect}
+      onLoad={onLoad}
+      edgeTypes={edgeTypes}
+      connectionLineComponent={FloatingConnectionLine}
+    >
+      <MiniMap />
+      <Controls />
+      <Background />
+    </ReactFlow>
+  );
+};
+
+export default NodeAsHandleFlow;

example/src/FloatingEdges/utils.ts

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+import { Position, ArrowHeadType, Node } from 'react-flow-renderer';
+
+function getNodeIntersection(source: Node, target: Node) {
+  // https://math.stackexchange.com/questions/1724792/an-algorithm-for-finding-the-intersection-point-between-a-center-of-vision-and-a
+  const { width: sourceWidth, height: sourceHeight, position: sourcePosition } = source.__rf;
+  const targetPosition = target.__rf.position;
+
+  const w = sourceWidth / 2;
+  const h = sourceHeight / 2;
+
+  const x2 = sourcePosition.x + w;
+  const y2 = sourcePosition.y + h;
+  const x1 = targetPosition.x;
+  const y1 = targetPosition.y;
+
+  const xx1 = (x1 - x2) / (2 * w) - (y1 - y2) / (2 * h);
+  const yy1 = (x1 - x2) / (2 * w) + (y1 - y2) / (2 * h);
+  const a = 1 / (Math.abs(xx1) + Math.abs(yy1));
+  const xx3 = a * xx1;
+  const yy3 = a * yy1;
+  const x = w * (xx3 + yy3) + x2;
+  const y = h * (-xx3 + yy3) + y2;
+
+  return [x, y];
+}
+
+function getEdgePosition(node: Node, x: number, y: number) {
+  const n = { ...node.__rf.position, ...node.__rf };
+  const nx = Math.round(n.x);
+  const ny = Math.round(n.y);
+  const px = Math.round(x);
+  const py = Math.round(y);
+
+  if (px <= nx + 1) {
+    return Position.Left;
+  }
+  if (px >= nx + n.width - 1) {
+    return Position.Right;
+  }
+  if (py <= ny + 1) {
+    return Position.Top;
+  }
+  if (py >= n.y + n.height - 1) {
+    return Position.Bottom;
+  }
+
+  return Position.Top;
+}
+
+export function getArrow(source: any, target: any) {
+  const [sx, sy] = getNodeIntersection(source, target);
+  const [tx, ty] = getNodeIntersection(target, source);
+
+  const sourcePos = getEdgePosition(source, sx, sy);
+  const targetPos = getEdgePosition(target, tx, ty);
+
+  return {
+    sx,
+    sy,
+    tx,
+    ty,
+    label: null,
+    sourcePos,
+    targetPos,
+  };
+}
+
+export function createElements() {
+  const elements = [];
+  const center = { x: window.innerWidth / 2, y: window.innerHeight / 2 };
+
+  elements.push({ id: 'source', data: { label: 'Source', isTarget: false }, position: center });
+
+  for (let i = 0; i < 8; i++) {
+    const degrees = i * (360 / 8);
+    const radians = degrees * (Math.PI / 180);
+    const x = 250 * Math.cos(radians) + center.x;
+    const y = 250 * Math.sin(radians) + center.y;
+
+    elements.push({ id: `${i}`, data: { label: 'Target', isTarget: true }, position: { x, y } });
+
+    if (i % 2 === 0) {
+      elements.push({
+        id: `source-${i}`,
+        source: 'source',
+        target: `${i}`,
+        type: 'floating',
+        arrowHeadType: ArrowHeadType.Arrow,
+      });
+    }
+  }
+
+  return elements;
+}