Add "switch" method to element.classList property

switch.js

Object.defineProperty(DOMTokenList.prototype, 'switch', {
	writable: false,
	enumerable: false,
	configurable: false,

	value (...list) {
		const el = this
		const matchedClass = list.filter(cls => el.contains(cls))

		if (!matchedClass.length) {
			el.add(list[0])
			return
		}

		el.add(list[list.indexOf(matchedClass[0]) + 1] || list[0])
		el.remove(matchedClass)
	}
})

How to use:

// Trigger on a specific event
document.querySelector('.element').classList.switch('class1', 'class2', 'class3', 'class4')

If the element already has a class that's in that list, it will start from this specific class.

Working Example

// Todo : throw errors if class isn't provided