import { AESEncryptionService } from "./aes";
/**
 * The default field used to store encrypted data in events.
 */
export declare const LEGACY_DEFAULT_EVENT_ENCRYPTION_FIELD = "encrypted";
/**
 * Available types to control the top-level fields of the event that will be
 * encrypted. Can be a single field name, an array of field names, a function
 * that returns `true` if a field should be encrypted, or `false` to disable all
 * event encryption.
 */
export type LEGACY_EventEncryptionFieldInput = string | string[] | ((field: string) => boolean) | false;
export declare namespace LEGACY_V0Service {
    interface Options {
        /**
         * The key or keys used to encrypt and decrypt data. If multiple keys are
         * provided, the first key will be used to encrypt data and all keys will be
         * tried when decrypting data.
         */
        key: string | string[];
        /**
         * If `true`, the encryption middleware will only encrypt using the legacy
         * V0 AES encryption service. This is useful for transitioning all services
         * to using the new encryption service before then removing the flag and
         * moving all encryption to LibSodium.
         */
        forceEncryptWithV0: boolean;
        /**
         * The top-level fields of the event that will be encrypted. Can be a single
         * field name, an array of field names, a function that returns `true` if a
         * field should be encrypted, or `false` to disable all event encryption.
         *
         * By default, the top-level field named `"encrypted"` will be encrypted
         * (exported as `DEFAULT_ENCRYPTION_FIELD`).
         */
        eventEncryptionField?: LEGACY_EventEncryptionFieldInput;
    }
}
export declare class LEGACY_V0Service {
    protected options: LEGACY_V0Service.Options;
    readonly service: AESEncryptionService;
    constructor(options: LEGACY_V0Service.Options);
    fieldShouldBeEncrypted(field: string): boolean;
    encryptEventData(data: Record<string, unknown>): unknown;
}