// Modified from https://gist.github.com/IbeVanmeenen/4e3e58820c9168806e57530563612886
// which is based on https://stackoverflow.com/questions/3177836/how-to-format-time-since-xxx-e-g-4-minutes-ago-similar-to-stack-exchange-site

const epochs = [
	["year", 31536000],
	["month", 2592000],
	["day", 86400],
	["hour", 3600],
	["minute", 60],
	["second", 1]
] as const

const getDuration = (timeAgoInSeconds: number) => {
	for (let [name, seconds] of epochs) {
		const interval = Math.floor(timeAgoInSeconds / seconds)

		if (interval >= 1) {
			return {
				interval: interval,
				epoch: name
			}
		}
	}

	return {
		interval: 0,
		epoch: "second"
	}
}

const timeAgo = (date: Date) => {
	const timeAgoInSeconds = Math.floor(
		(new Date().getTime() - new Date(date).getTime()) / 1000
	)
	const { interval, epoch } = getDuration(timeAgoInSeconds)
	const suffix = interval === 1 ? "" : "s"

	return `${interval} ${epoch}${suffix} ago`
}

const timeUntil = (date: Date) => {
	const timeUntilInSeconds = Math.floor(
		(new Date(date).getTime() - new Date().getTime()) / 1000
	)
	const { interval, epoch } = getDuration(timeUntilInSeconds)
	const suffix = interval === 1 ? "" : "s"

	return `in ${interval} ${epoch}${suffix}`
}

export { timeAgo, timeUntil }