/** Unix seconds → localized date-time. `locale`/`timeZone` exist for deterministic tests. */
export function formatTime(unixSeconds: number, locale?: string, timeZone?: string): string {
	return new Intl.DateTimeFormat(locale, {
		dateStyle: "medium",
		timeStyle: "medium",
		timeZone,
	}).format(new Date(unixSeconds * 1000));
}

const BYTE_UNITS = ["KiB", "MiB", "GiB", "TiB"] as const;

export function formatBytes(bytes: number): string {
	if (bytes < 1024) return `${bytes} B`;
	let value = bytes;
	let unit: string = BYTE_UNITS[0];
	for (const next of BYTE_UNITS) {
		unit = next;
		value /= 1024;
		if (value < 1024) break;
	}
	return `${value.toFixed(1)} ${unit}`;
}

/** Microseconds → milliseconds with one decimal, e.g. 1234 → "1.2 ms". */
export function formatMicros(micros: number): string {
	return `${(micros / 1000).toFixed(1)} ms`;
}
