Repository: excalidraw/excalidraw
File: src/element/linearElementEditor.ts (TypeScript)

Code before:
      return false;
    }
    const clickedPointIndex = LinearElementEditor.getPointIndexUnderCursor(
      element,
      appState.zoom,
      scenePointer.x,
      scenePointer.y,
    );
    if (clickedPointIndex >= 0) {
      return false;
    }
    const points = LinearElementEditor.getPointsGlobalCoordinates(element);
    if (points.length >= 3) {
      return false;
    }
    const centerX = (points.at(0)![0] + points.at(-1)![0]) / 2;
    const centerY = (points.at(0)![1] + points.at(-1)![1]) / 2;
    const threshold =
      (LinearElementEditor.POINT_HANDLE_SIZE * 2) / appState.zoom.value;
    if (
      Math.abs(scenePointer.x - centerX) <= threshold &&
      Math.abs(scenePointer.y - centerY) <= threshold
    ) {
      return true;
    }
    return false;
  };

  static getMidPoint(linearElementEditor: LinearElementEditor) {
    const { elementId } = linearElementEditor;
    const element = LinearElementEditor.getElement(elementId);
    if (!element) {
      return null;
    }
    const points = LinearElementEditor.getPointsGlobalCoordinates(element);

    const centerX = (points.at(0)![0] + points.at(-1)![0]) / 2;
    const centerY = (points.at(0)![1] + points.at(-1)![1]) / 2;
    return [centerX, centerY];
  }

  static handlePointerDown(
    event: React.PointerEvent<HTMLCanvasElement>,
    appState: AppState,
    history: History,
    scenePointer: { x: number; y: number },
    linearElementEditor: LinearElementEditor,
  ): {
    didAddPoint: boolean;
    hitElement: NonDeleted<ExcalidrawElement> | null;
    linearElementEditor: LinearElementEditor | null;

Review comment (refactor):
```suggestion

    const midPoint = this.getMidPoint(linearElementEditor);
    if (midPoint) {
      const threshold =
        LinearElementEditor.POINT_HANDLE_SIZE / appState.zoom.value;
      const distance = distance2d(
        midPoint[0],
        midPoint[1],
        scenePointer.x,
        scenePointer.y,
      );
      return distance <= threshold;
    }
    return false;
```

let's reuse got the getMidPoint logic and `distance2d` helper 

Code after:
    if (!element) {
      return false;
    }
    const clickedPointIndex = LinearElementEditor.getPointIndexUnderCursor(
      element,
      appState.zoom,
      scenePointer.x,
      scenePointer.y,
    );
    if (clickedPointIndex >= 0) {
      return false;
    }
    const points = LinearElementEditor.getPointsGlobalCoordinates(element);
    if (points.length >= 3) {
      return false;
    }

    const midPoint = this.getMidPoint(linearElementEditor);
    if (midPoint) {
      const threshold =
        LinearElementEditor.POINT_HANDLE_SIZE / appState.zoom.value;
      const distance = distance2d(
        midPoint[0],
        midPoint[1],
        scenePointer.x,
        scenePointer.y,
      );
      return distance <= threshold;
    }
    return false;
  };

  static getMidPoint(linearElementEditor: LinearElementEditor) {
    const { elementId } = linearElementEditor;
    const element = LinearElementEditor.getElement(elementId);
    if (!element) {
      return null;
    }
    const points = LinearElementEditor.getPointsGlobalCoordinates(element);

    return centerPoint(points[0], points.at(-1)!);
  }

  static handlePointerDown(
    event: React.PointerEvent<HTMLCanvasElement>,
    appState: AppState,
    history: History,
    scenePointer: { x: number; y: number },
    linearElementEditor: LinearElementEditor,
  ): {
    didAddPoint: boolean;