export type Shortcut = {
	famSlug: string;
	famName: string;
	userName: string; // '' for parents (no handle in URL)
};

const KEY = 'fam_shortcut';

export function recordShortcut(entry: Shortcut) {
	if (typeof localStorage === 'undefined') return;
	localStorage.setItem(KEY, JSON.stringify(entry));
}

export function readShortcut(): Shortcut | null {
	if (typeof localStorage === 'undefined') return null;
	try {
		const raw = localStorage.getItem(KEY);
		if (!raw) return null;
		const s = JSON.parse(raw) as Shortcut;
		// Self-heal the old poisoned entry: a write that fell back to
		// page.params.fam while page.data.fam was null stored the PB id as
		// both slug and name ({famSlug: id, famName: id}). A real slug is
		// never identical to the display name AND a 15-char PB id.
		if (s && s.famSlug === s.famName && /^[a-z0-9]{15}$/.test(s.famSlug || '')) {
			localStorage.removeItem(KEY);
			return null;
		}
		return s;
	} catch {
		return null;
	}
}

export function shortcutTarget(s: Shortcut): string {
	return s.userName ? `/${s.famSlug}/${s.userName}` : `/${s.famSlug}`;
}