/** One persistent notification — unlike a transient toast, it stays in the log until dismissed. */
export interface NotificationEntry<TMeta = unknown> {
    id: string;
    /** Severity/category (`"info"`, `"success"`, `"warning"`, `"danger"`, or a game kind). */
    kind: string;
    title: string;
    body?: string;
    /** Creation time from the injected clock. */
    at: number;
    read: boolean;
    meta?: TMeta;
}
/** Fields accepted by {@link NotificationStore.push}. */
export interface NotificationInput<TMeta = unknown> {
    id?: string;
    kind?: string;
    title: string;
    body?: string;
    at?: number;
    meta?: TMeta;
}
/** Filter for {@link NotificationStore.list}. */
export interface NotificationFilter {
    kind?: string;
    unreadOnly?: boolean;
}
/** Serializable, observable log of persistent notifications with read tracking. */
export interface NotificationStore<TMeta = unknown> {
    push(input: NotificationInput<TMeta>): NotificationEntry<TMeta>;
    /** Newest-first; filter by kind and/or unread. Stable identity between changes for the unfiltered read. */
    list(filter?: NotificationFilter): readonly NotificationEntry<TMeta>[];
    unreadCount(): number;
    markRead(id: string): void;
    markAllRead(): void;
    remove(id: string): boolean;
    clear(): void;
    subscribe(listener: () => void): () => void;
    snapshot(): readonly NotificationEntry<TMeta>[];
    restore(snapshot: readonly NotificationEntry<TMeta>[]): void;
}
/** Options for {@link createNotificationCenter}. */
export interface NotificationCenterOptions {
    /** Injected clock (ms). Default `Date.now`. */
    now?: () => number;
    /** Keep only the newest `cap` notifications. Default 100; 0 = unbounded. */
    cap?: number;
}
/**
 * A persistent notification log with read/unread tracking — the "notification
 * center" surface toasts don't cover. Newest-first, capped, serializable, and
 * observable; a game pushes durable events (quest updates, trades, party news)
 * here and a HUD renders the list + an unread badge. `snapshot`/`restore`
 * round-trip through a save.
 *
 * @capability notification-center persistent, read-tracked notification log (newest-first, capped, serializable) behind an unread badge — the durable counterpart to transient toasts
 */
export declare function createNotificationCenter<TMeta = unknown>(options?: NotificationCenterOptions): NotificationStore<TMeta>;