/**
 * Routes whose page data must not be refetched in the background: edit pages
 * hold in-progress work, and refreshing the login form is pointless.
 */
export const EXCLUDED_ROUTES: Record<string, true> = {
	'/login': true,
	'/grocery/[id]': true,
	'/projects/[projectId]/routine/[routineId]': true,
};

export interface RefreshConditions {
	/** `$page.route.id`; null when no route matched yet. */
	routeId: string | null | undefined;
	/** Document is visible (not a backgrounded tab). */
	visible: boolean;
	/** Browser reports a network connection. */
	online: boolean;
	/** A navigation or form action is already in flight. */
	navigating: boolean;
}

/** A background refetch may re-run the page load only if nothing is at stake. */
export function shouldAutoRefresh({
	routeId,
	visible,
	online,
	navigating,
}: RefreshConditions): boolean {
	if (!routeId || routeId in EXCLUDED_ROUTES) return false;
	return visible && online && !navigating;
}