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const util = require('util');

const R = require('ramda');
const chalk = require('chalk');
const jsondiffpatch = require('jsondiffpatch');

const toJson = require('./to-json');

let prefix;
let coloredOutput = false;

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/* eslint-disable no-return-assign */
const chalk = require('chalk');
const ora = require('ora');
const prettyMs = require('pretty-ms');
const throttle = require('lodash/throttle');

const getHeapUsed = throttle(
  () => {
    const heapUsed = process.memoryUsage().heapUsed / 1024 / 1024;
    return Math.round(heapUsed, 2);

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/* 

Problem

We have a function that updates objects and generates audit records of the changes. 
Think about financial systems or just any app where it's useful to know who made changes to what. 

Audit records needs to be saved to the DB as well as updates to objects, but ideally
we would want to execute business logic, accumulate all updates and audit records in memory
and then save it to DB all at once. Let's look at the specifics.

Restuta

/* tl;dr of the problem 
 - We have a funtion that updates objects and produces two values [updates, auditLogRecord]. 
 Let's call it "applyChangesWithAuditLog"
 - We need to use this function in the context of another function (let's call it "update") and that another function should not be
 aware of the fact that that auditLogRecord's are being produced and collected.
 - When function "update" is executed, we want to collect all auditLogRecords that originated from calls 
 to "applyChangesWithAuditLog" inside "update" function. 
 - Then we want to save all collected auditLog items to DB.
 
 Code below achieves this by building a functional wrapper.

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// step module

const applyUpdates = () => {};

const updateStepBody = useDb => (stepBody, updates) => {
  const updatedBody = applyUpdates(stepBody, updates);

  useDb(transaction => {
    createHistoryRecord(updatedBody, updates);
  });

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// original version with binding to module instance

const { createAuditLogRecords } = require('../commands');

const getStepFactory = require('./get-factory-by-type');
const { createStep, updateStep  } = require('./commands');
const applyStepUpdates = require('./apply-step-updates');

const createContainer = (items = []) => ({
  getAll: () => items,

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// prototype of a pattern that allows to collect certain objects/operations
// during function exectution

const createContainer = (items = []) => ({
  getAll: () => items,
  add: x => items.push(x),
});

const applyUpdates = ({ onNewAuditLogRecord }) => x => {
  onNewAuditLogRecord(x);

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// effect functor
const Effect = f => ({
  map: g => Effect(x => g(f(x))),
  run: x => f(x),
  join: x => f(x),
  chain: f =>
    Effect(f)
      .map(g)
      .join(),
  ap: eff => {

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// https://runkit.com/embed/ogydgfyotoqc

var base64 = require("base-64")
const R = require('ramda')
var utf8 = require('utf8')

var text = 'Yeah, right?!'
const encode = R.pipe(utf8.encode, base64.encode)
const encodeN = R.pipe(...R.times(() => encode, 16))

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console.clear()
async function main() {

    const delay = time=>new Promise(resolve => setTimeout(()=>resolve(), time))
    const functionInvocationsObservable = new Rx.Subject()
        .bufferTime(/* buffer time*/ 500, /* restart buffer, -1 means never */ -1,  /* maxBufferSize*/ 3)
        .filter(x => x.length > 0)
//         .subscribe(console.log)
    
    const batchify = func => {