import { formatAbsoluteDate } from '@/lib/relativeDate'

const ISO_DAY_PREFIX = /^(\d{4})-(\d{2})-(\d{2})/
const ISO_DAY = /^(\d{4})-(\d{2})-(\d{2})$/

export function isBlank(value: unknown) {
	return value === null || value === undefined || value === ''
}

export function charCount(text: string) {
	return Array.from(text).length
}

export function isIsoDay(value: unknown): value is string {
	if (typeof value !== 'string') {
		return false
	}
	const match = ISO_DAY.exec(value)
	if (!match) {
		return false
	}
	const [year, month, day] = [Number(match[1]), Number(match[2]), Number(match[3])]
	const date = new Date(year, month - 1, day)
	return date.getFullYear() === year && date.getMonth() === month - 1 && date.getDate() === day
}

export function asText(value: unknown) {
	return value === null || value === undefined ? '' : String(value)
}

export function asNumber(value: unknown) {
	if (typeof value === 'number' && Number.isFinite(value)) {
		return value
	}
	if (typeof value === 'string' && value.trim() !== '' && Number.isFinite(Number(value))) {
		return Number(value)
	}
	return null
}

export function asBoolean(value: unknown) {
	return typeof value === 'boolean' ? value : null
}

export function formatDayValue(value: string) {
	const match = ISO_DAY_PREFIX.exec(value)
	if (!match) {
		return value
	}
	return formatAbsoluteDate(new Date(Number(match[1]), Number(match[2]) - 1, Number(match[3])))
}

export function freeSentinel(taken: string[], base = '__none__') {
	let sentinel = base
	while (taken.includes(sentinel)) {
		sentinel += '_'
	}
	return sentinel
}

export function sameValue(left: unknown, right: unknown) {
	if (Array.isArray(left) && Array.isArray(right)) {
		return (
			left.length === right.length &&
			left.every((item, index) => Object.is(item, right[index]))
		)
	}
	return Object.is(left, right)
}