import * as O from "fp-ts/lib/Option"

export function renderIfNoFetchOrFetchDefined<F, R>(
	fetch: Record<string, F> | undefined,
	name: string,
	renderer: (fetch: F | undefined) => O.Option<R>,
): O.Option<R> {
	if (fetch === undefined) {
		return renderer(undefined)
	} else {
		const f: F | undefined = fetch[name]
		if (f === undefined) {
			return O.none
		} else {
			return renderer(f)
		}
	}
}

export function writeEmptyStringOrNull(s: string | null | undefined, emptyStringInsteadOfNull: boolean): string | null {
	if (s === null || s === undefined) {
		return emptyStringInsteadOfNull ? "" : null
	} else {
		return s
	}
}

export function filterDouble(value: string): number | null {
	if (value === "") {
		return null
	}
	const result = Number(value)
	return Number.isNaN(result) ? null : result
}

export function formatDateTime(date: Date): string {
	return date.toISOString().replace(/\.\d{3}Z$/, "+0000")
}

export function formatDateTimeIsoString(date: string): string {
	return date.replace(/\.\d{3}Z$/, "+0000")
}

export function formatDate(date: Date): string {
	return date.toISOString().replace(/T.*/, "")
}

export function isEmpty(obj: object) {
	for (const _x in obj) {
		return false
	}
	return true
}