Implement mySetInterval() and myClearInterval() as functions that behave exactly like setInterval() and clearInterval().

mySetInterval.js

/*

Prompt: Implement mySetInterval() and myClearInterval() as functions that behave exactly like setInterval() and clearInterval(). Obviously, you’re not allowed to use setInterval() in your implementation, but everything else is fair game.
Time: This shouldn’t take too long - please don’t spend more than an hour working on it.
Rules: You may consult MDN for documentation, but you may not use any other resources.
Goals: We’re looking for clean code and quick implementation, so please send in your solution as soon as you finish.

*/

// ### MDN setInterval documentation
// https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/setInterval

// ### Behaviors
// 1. executes the callback every specified interval
// 2. once the mySetInterval function was run, it returns the intervalID
// 3. calls the myClearInterval function with intervalID can stop the according mySetInterval
// 4. supports 2 forms of input:
//    i.  `scope.setInterval(func, delay[, param1, param2, ...])` with extra params
//    ii. `scope.setInterval(code, delay)` with code in string

// ### Edge Case
// 1. when calling `setInterval` without specifying a valid delay value, the value will be set as 0

// ### Test Cases
// mySetInterval(function(a){console.log('hello1', a)}, 1000, 'abc')
//  => hello1 abc

// mySetInterval("console.log('hello2')", 1000)
//  => hello2

// mySetInterval(function(a){console.log('hello3', a)}, 'NaN', 'param1')
//  => hello3 param1

// mySetInterval()
//  => throw TypeError

// mySetInterval('1')
//  => nothing happened, same as setInterval('1')

// myClearInterval(intervalID)

(function(window) {
  let _timeoutIDMap = {};
  let _count = 0;

  function init() {
    window.mySetInterval = mySetInterval;
    window.myClearInterval = myClearInterval;
  }

  function mySetInterval() {
    if(arguments[0] !== undefined) {
      let intervalID = `${+new Date()}${_count++}`;
      let intervalTimer = new IntervalTimer();

      _timeoutIDMap[intervalID] = intervalTimer;
      intervalTimer.mySetInterval.apply(intervalTimer, arguments);

      return intervalID;
    } else {
      throw new TypeError("Failed to execute 'setInterval' on 'Window': 1 argument required, but only 0 present.");
    }
  }

  function myClearInterval(intervalID) {
    let intervalTimer = _timeoutIDMap[intervalID];

    if(intervalTimer) {
      intervalTimer.myClearInterval();
      delete _timeoutIDMap[intervalID];
    }
  }

  init();
})(window)

function IntervalTimer() {
  this.timeoutID = null;
}

IntervalTimer.prototype.mySetInterval = function(callback, timeInterval) {
  let args = Array.prototype.slice.call(arguments);
  let params = Array.prototype.slice.call(arguments, 2);
  // to handle the edge case 1
  timeInterval = isNaN(Number(timeInterval)) ? 0 : Number(timeInterval);

  this.timeoutID = window.setTimeout(() => {
    if(callback instanceof Function) {
      callback.apply(window, params);
    } else {
      window.setTimeout(callback, 0);
    }
    this.mySetInterval.apply(this, args);
  }, timeInterval);
}

IntervalTimer.prototype.myClearInterval = function() {
  window.clearTimeout(this.timeoutID);
}