export function relativeTime(iso: string): string {
	const then = new Date(iso).getTime();
	const diff = Date.now() - then;
	const abs = Math.abs(diff);
	const mins = Math.round(abs / 60000);
	const suffix = diff >= 0 ? "ago" : "from now";
	if (abs < 60000) return "just now";
	if (mins < 60) return `${mins}m ${suffix}`;
	const hours = Math.round(mins / 60);
	if (hours < 24) return `${hours}h ${suffix}`;
	const days = Math.round(hours / 24);
	if (days < 30) return `${days}d ${suffix}`;
	return new Date(iso).toLocaleDateString();
}

export function formatDateTime(iso: string): string {
	return new Date(iso).toLocaleString(undefined, {
		year: "numeric",
		month: "short",
		day: "numeric",
		hour: "2-digit",
		minute: "2-digit",
		timeZoneName: "short",
	});
}

/** Returns a human "expires in Xm" string, or "expired" if past. */
export function expiresIn(iso: string): { text: string; expired: boolean; urgent: boolean } {
	const diff = new Date(iso).getTime() - Date.now();
	if (diff <= 0) return { text: "expired", expired: true, urgent: false };
	const mins = Math.floor(diff / 60000);
	if (mins < 60) return { text: `expires in ${mins}m`, expired: false, urgent: mins < 10 };
	const hours = Math.floor(mins / 60);
	return { text: `expires in ${hours}h ${mins % 60}m`, expired: false, urgent: false };
}