import type { EmailQueue } from "./index.mjs";
/** A minimal subset of the unstorage \`Storage\` interface — we only need
*  these four methods, so we don't force a peer dep. Users pass any
*  unstorage instance (redis, upstash, fs, mongodb, etc.). */
export interface UnstorageLike {
	getItem: <T = unknown>(key: string) => Promise<T | null>;
	setItem: (key: string, value: unknown) => Promise<void>;
	removeItem: (key: string) => Promise<void>;
	getKeys: (base?: string) => Promise<string[]>;
}
export interface UnstorageQueueOptions {
	storage: UnstorageLike;
	/** Key prefix. Default: \`"unemail:queue:"\`. */
	prefix?: string;
}
/** Queue backed by any unstorage driver — turn the in-memory queue into a
*  durable one by swapping this in. Each item lives under
*  \`\${prefix}\${id}\`. */
export declare function unstorageQueue(options: UnstorageQueueOptions): EmailQueue;
export default unstorageQueue;