Debounce.js

function debounce(callback, delay) {
  let timer;
  return function (...args) {
    clearTimeout(timer);
    timer = setTimeout(() => {
      callback(...args);
    }, delay);
  };
}

function throttle(callback, delay) {
  let inThrottled = false;
  return function (...args) {
    if (!inThrottled) {
      inThrottled = true;
      callback.apply(this, args);
      setTimeout(() => {
        inThrottled = false;
      }, delay);
    }
  };
}

// If leading is true, it will invoke immediately after function call
// If trailing is true, it is class debounce
// If both are true, it will invoke at first and then it will invoke at last
function debounceWithTraingAndLeading(
  cb,
  time,
  { leading = true, trailing = true }
) {
  let timerId;

  return function (...args) {
    const isLeadingCall = leading && !timerId;
    if (isLeadingCall) {
      cb(...args);
    }

    if (timerId) {
      clearInterval(timerId);
    }

    timerId = setTimeout(() => {
      if (trailing && !isLeadingCall) {
        cb(...args);
      }
      timerId = null;
    }, time);
  };
}