hashMapObservable.js

import isClient from 'helpers/isClientSideRender';

function isObject(val) {
  return Object.prototype.toString.call(val) === '[object Object]';
}

function fn(dest, obj, rootPath, myColl) {
  return Object.keys(obj).reduce(
    (acc, key) => {
      const val = obj[key];
      const path = rootPath ? `${rootPath}.${key}` : key;

      if (isObject(val)) {
        acc[key] = {};
        fn(acc[key], val, path, myColl);
      } else {
        Object.defineProperty(acc, key, {
          get: () => {
            myColl.set(path, val);
            return val;
          },
          set: (newVal) => {
            console.log('SET:', path, newVal);
          }
        });
      }

      return acc;
    },
    dest
  );
}

function addNewItemsToHashMap(parsedItems, key, value) {
  key.split('.').reduce(
    (acc, field, idx, arr) => {
      if (arr.length === idx + 1) {
        acc[field] = value;
        return acc;
      }

      if (!isObject(acc[field])) {
        acc[field] = {};
      }

      return acc[field];
    },
    parsedItems
  );
}

function setObservable(name, hashMap) {
  if (isClient) {
    const myColl = new Map();
    const hashMapCollectionKey = `${name}-observable`;

    setInterval(
      () => {
        const storedItems = localStorage.getItem(hashMapCollectionKey);
        const parsedItems = JSON.parse(storedItems) || {};

        for (const [key, value] of myColl.entries()) {
          addNewItemsToHashMap(parsedItems, key, value);
        }

        localStorage.setItem(hashMapCollectionKey, JSON.stringify(parsedItems));
      }, 2000
    );

    return fn({}, hashMap, '', myColl);
  }

  return hashMap;
}

export default setObservable;