export type CookieSameSite = 'Lax' | 'Strict' | 'None' | 'lax' | 'strict' | 'none';
export interface CookieOptions {
    /** Path attribute. Defaults to `'/'`. Pass `null` to omit. */
    path?: string | null;
    /** Domain attribute. */
    domain?: string;
    /** Lifetime in seconds. Defaults to one year. Pass `null` to omit (session cookie). */
    maxAge?: number | null;
    /** Explicit expiration date. Takes precedence over `maxAge` when both are set. */
    expires?: Date;
    /** Restrict the cookie to HTTPS connections. */
    secure?: boolean;
    /** Same-site policy. Defaults to `'Lax'`. Pass `null` to omit. */
    sameSite?: CookieSameSite | null;
    /** Mark the cookie as partitioned (CHIPS). */
    partitioned?: boolean;
}
/**
 * Read a cookie by key.
 *
 * - On the client, the cookie is read from `document.cookie`.
 * - On the server, pass the raw `Cookie` request header via `cookieHeader`
 *   (e.g. from `useSSRContext().event.node.req.headers.cookie` in Nuxt) to
 *   resolve the value during SSR. Without it, the function returns `null`.
 */
export declare function getCookie(key: string, cookieHeader?: string): string | null;
/**
 * Write a cookie via `document.cookie` with full attribute support.
 *
 * No-op on the server. `HttpOnly` is intentionally omitted as it cannot be set
 * from `document.cookie` (browsers reject it).
 */
export declare function setCookie(key: string, value: string, options?: CookieOptions): void;
/**
 * Delete a cookie by writing `max-age=0`. `path` and `domain` must match the
 * cookie's original attributes for the browser to actually drop it.
 */
export declare function deleteCookie(key: string, options?: Pick<CookieOptions, 'path' | 'domain'>): void;