batching for snapshot feature in svelte-kit

snapshot.ts

/* eslint-disable @typescript-eslint/no-explicit-any */
import { getContext, setContext } from 'svelte';

type Snapshot<T = any> = {
  capture: () => T;
  restore: (value: T) => void;
};

export function provideSnapshot() {
  const snapshots: Record<string, Snapshot> = {};
  function snap<T>(key: string, snapshot: Snapshot<T>) {
    snapshots[key] = snapshot;
  }

  setContext('snapshot', snap);

  const registry = {
    capture() {
      return Object.entries(snapshots).reduce((acc, [key, snapshot]) => {
        acc[key] = snapshot.capture();
        return acc;
      }, {} as Record<string, any>);
    },
    restore(value: Record<string, any>) {
      Object.entries(snapshots).forEach(([key, snapshot]) => {
        snapshot.restore(value[key]);
      });
    },
  };

  return { registry, snap };
}

export type SnapshotContext = ReturnType<typeof provideSnapshot>['snap'];

export function useSnapshot() {
  return getContext<SnapshotContext>('snapshot');
}