/**
 * ExplodeSettings content type for Convos.
 *
 * Matches the iOS ExplodeSettingsCodec:
 * - Content type: convos.org/explode_settings:1.0
 * - Payload: JSON-encoded { expiresAt: ISO8601 string }
 * - fallback: "Conversation expires at {date}"
 * - shouldPush: true (so receiving clients can trigger their cleanup flow)
 *
 * Sent by the creator immediately before `removeMembers(all others)` +
 * `leaveGroup()` (per ADR 004 C9 amendment / ADR 011 §5). Receiving
 * clients drop the conversation locally on whichever arrives first: the
 * ExplodeSettings message or the MLS remove commit.
 */
import type { ContentTypeId, EncodedContent } from "@xmtp/node-bindings";
import type { ContentCodec } from "@xmtp/content-type-primitives";
import type { DecodedMessage } from "@xmtp/node-sdk";
export declare const ContentTypeExplodeSettings: ContentTypeId;
export interface ExplodeSettingsContent {
    /** ISO 8601 timestamp when the conversation expires. */
    expiresAt: string;
}
export declare class ExplodeSettingsCodec implements ContentCodec<ExplodeSettingsContent> {
    get contentType(): ContentTypeId;
    encode(content: ExplodeSettingsContent): EncodedContent;
    decode(content: EncodedContent): ExplodeSettingsContent;
    fallback(content: ExplodeSettingsContent): string | undefined;
    shouldPush(_content: ExplodeSettingsContent): boolean;
}
/**
 * Encode an ExplodeSettings message directly as EncodedContent. Used by
 * senders that construct the wire payload without instantiating the codec.
 */
export declare function encodeExplodeSettings(expiresAt: Date): EncodedContent;
export declare function isExplodeSettingsMessage(message: DecodedMessage): boolean;
/**
 * Extract ExplodeSettings content from a DecodedMessage. When the codec is
 * registered on the client (the default), the SDK has already decoded the
 * payload and the first branch returns the typed object directly. The
 * EncodedContent fallback handles callers that hand the helper a raw
 * `{ content: Uint8Array }` object (test mocks, in-process forwarding, or
 * any future code path that bypasses the codec registry); without this
 * branch those callers would silently get `undefined`.
 *
 * Note: when an unregistered codec runs through the SDK proper the SDK
 * sets `content = undefined`, so the early-exit kicks in and the fallback
 * is unreachable. The fallback is load-bearing only for callers that
 * supply EncodedContent directly.
 */
export declare function getExplodeSettingsContent(message: DecodedMessage): ExplodeSettingsContent | undefined;